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    Wyświetlanie 1-88 z 88
    Tytuł:
    Energy efficiency – selected thermo-ecological problems
    Autorzy:
    Ziębik, Andrzej
    Stanek, Wojciech
    Powiązania:
    https://bibliotekanauki.pl/articles/239928.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    energy efficiency
    system analysis
    exergy
    thermo-ecology
    energy ecological
    efficiency
    Opis:
    The paper is devoted to some problems connected with last modification of EU directive on energy efficiency, viz.: free choice of the measure concerning the improvement of energy efficiency, i.e. final or primary energy consumption, corresponding energy savings or energy-consumption index; however without cumulative consumption or cumulative savings of primary energy. In EU directive it has been stressed the importance of measurements systems (reliable measurement information); but has not been recommended any advanced validation of measurements results, nor energy auditing or algorithms of calculating the energy savings due to improvement of energy efficiency concerning large industrial plants. Evaluation of complex buildings should be realized by means of the system method (input-output analysis). The separate problem is devoted to application of thermo-ecological approach in the analysis of complete results of improving the energy efficiency. Human activity is connected with the depletion of nonrenewable resources, including primary energy, due to not only production of consumer goods but also the necessity of compensating the unfavourable effects of harmful emissions from energy-technological processes. Therefore the index of energy-ecological efficiency has been proposed as the most competent evaluation of improvement energy efficiency of production processes and systems.
    Źródło:
    Archives of Thermodynamics; 2020, 41, 2; 277-299
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Power system stability with parallel active filter ensuring compensation of capacitive reactive power of a resonant LC circuit
    Autorzy:
    Płatek, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/201301.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    parallel active filter
    passive filter
    system stability analysis
    Opis:
    This paper presents an analysis allowing for the determination of the differential equation describing the circuit of the active filter inverter output current control with an additional measurement of input voltage. The resulting equation allows to determine the conditions that ensure stable operation of the filter with the load in form of a resonant LC circuit. Analysis results were confirmed by computer simulation and experimental studies of commercial active filter.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 2; 353-361
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Assessment of Reliability of Measurement Data and Adequacy of the Measurement Systems in Improving Quality of Casting Products
    Autorzy:
    Fedoryszyn, A.
    Brzeziński, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/380770.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    quality control
    cast quality
    measurement system analysis
    repeatability analysis
    reproducibility analysis
    kontrola jakości
    jakość odlewu
    analiza systemu pomiarowego
    analiza powtarzalności
    analiza odtwarzalności
    Opis:
    The study summarises the analysis of reliability assessment of measurements of a selected critical property of a high-precision casting product. Measurement data must be sufficiently reliable to be used in decision-making relating to quality control and the selection of the casting manufacturing technology. The applied procedure is illustrated by study of the variability range of readouts depending on the measurement conditions, obtained by the computer methods. The applied R&R (Repeatability and Reproducibility) procedure is major component of the widely employed Measurement System Analysis (MSA).
    Źródło:
    Archives of Foundry Engineering; 2015, 15, 3 spec.; 124-126
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Zmiana społeczna w perspektywie teorii systemu światowego Immanuela Wallersteina
    Social Change in Immanuel Wallerstein’s World-System Theory
    Autorzy:
    Osicka-Kajda, Anna
    Powiązania:
    https://bibliotekanauki.pl/articles/2137709.pdf
    Data publikacji:
    2009
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    social change
    modernization theories
    world-system analysis
    historical sociology
    zmiana społeczna
    teorie modernizacji
    analiza systemu światowego
    socjologia historyczna
    Opis:
    The purpose of the article is to analyse Immanuel Wallerstein's approach towards social change and to compare it with the concept of macrosocial change in modernization theories. The main thesis proposed by the authoress is that although Immanuel Wallerstein declares that perception of social change as framed by the 'ahistorical models' (such bias being typical of modernization theories) should be abandoned, he nevertheless advances a model which is equally ahistorical.
    Celem artykułu jest przybliżenie i analiza ujęcia zmiany społecznej w teorii systemu światowego Immanuela Wallersteina oraz porównanie jego koncepcji z ujęciem zmiany w teoriach modernizacji. Autorka stoi na stanowisku, że choć Wallerstein deklaruje konieczność zerwania z ujmowaniem zmiany społecznej w ramach „modeli ahistorycznych” (ku którym zwracają się teorie modernizacji), proponuje w istocie model równie ahistoryczny.
    Źródło:
    Studia Socjologiczne; 2009, 2(193); 77-108
    0039-3371
    Pojawia się w:
    Studia Socjologiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comprehensive approach to the inventory control system improvement
    Autorzy:
    Krajčovič, M.
    Plinta, D.
    Powiązania:
    https://bibliotekanauki.pl/articles/407413.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    inventory control system
    inventory analysis
    ABC/XYZ analysis
    Opis:
    This paper describes a methodology for inventory analysis and reduction, which was developed at the Department of Industrial Engineering, Faculty of Mechanical Engineering, University of Zilina. The methodology describes the optimal procedure for the application of basic analytical methods and tools in practice. The results of the analysis are in the algorithm linked to the subsequent actions realized to improve inventory management system and to minimize inventory level in the company. Described procedure is the result of methodology examination and verification in practical conditions of production enterprises. In the following sections of this paper, there are presented a comprehensive approach to the inventory analysis and the own algorithm, which contains 3 phases: inventory analysis on enterprise level, summary analysis of individual item groups and individual analysis of material items. In the last section, there are described examples of results from such analysis and conclusions. The presented approach is an attempt to create a universal procedure of analysis which integrates methods and tools described in various publications.
    Źródło:
    Management and Production Engineering Review; 2012, 3, 3; 34-44
    2080-8208
    2082-1344
    Pojawia się w:
    Management and Production Engineering Review
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparative analysis of multi-criteria decision making methods for the assessment of optimal SVC location
    Autorzy:
    Aydin, Faruk
    Gümüş, Bilal
    Powiązania:
    https://bibliotekanauki.pl/articles/2173650.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Borda count method
    FACTS
    MCDM
    optimal location
    PSAT
    voltage stability
    flexible alternating current transmission system
    power system analysis toolbox
    multi criteria decision making
    metoda liczenia Bordy
    podejmowanie decyzji wielokryterialnej
    lokalizacja optymalna
    stabilność napięcia
    elastyczne systemy przesyłowe prądu przemiennego
    narzędzia do analizy systemu zasilania
    Opis:
    The goal of multi-criteria decision making (MCDM) is to select the most appropriate of the alternatives by evaluating many conflicting criteria together. MCDM methods are widely available in the literature and have been used in various energy problems. The key problems studied in electrical power systems in recent years have included voltage instability and voltage collapse. Different flexible alternating current transmission systems (FACTS) equipment has been used for this purpose for decades, increasing voltage stability while enhancing system efficiency, reliability and quality of supply, and offering environmental benefits. Finding the best locations for these devices in terms of voltage stability in actual electrical networks poses a serious problem. Many criteria should be considered when determining the most suitable location for the controller. The aim of this paper is to provide a comparative analysis of MCDM techniques to be used for optimal location of a static VAR compensator (SVC) device in terms of voltage stability. The ideal location can be determined by means of sorting according to priority criteria. The proposed approach was carried out using the Power System Analysis Toolbox (PSAT) in MATLAB in the IEEE 14-bus test system. Using ten different MCDM methods, the most appropriate locations were compared among themselves and a single ranking list was obtained, integrated with the Borda count method, which is a data fusion technique. The application results showed that the methods used are consistent among themselves. It was revealed that the integrated model was an appropriate method that could be used for optimal location selection, providing reliable and satisfactory results to power system planners.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2022, 70, 2; art. no. e140555
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Performance evaluation on selection of formwork systems in high rise buildings using regression analysis and their impacts on project success
    Autorzy:
    Rajeshkumar, Viswanathan
    Sreevidya, V.
    Powiązania:
    https://bibliotekanauki.pl/articles/962264.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    deskowanie
    system deskowania
    analiza czynnikowa
    korelacja
    analiza regresji
    formwork system
    factor analysis
    correlation
    regression analysis
    Opis:
    The selection of the formwork system for high rise building affects the entire construction project duration and cost. The study reports the factors influencing the selection of different formwork system in the construction of high rise buildings through structural questionnaire survey from the client, contractor, consultant, and interviews with expert members. Total of 40 technical factors was identified from the literature and 220 filled questionnaires were received from the respondent. Relative Importance Index method is used to find the topmost factors affecting the selection of formwork system. Additionally, from factor analysis 22 factors were identified to have a correlation with one another. Regression analysis reveals that duration of the project, maintenance cost, adaptability, and safety have impact on formwork selection across time, cost and quality. These findings could potentially increase the construction company’s existing knowledge in relation to formwork selection.
    Źródło:
    Archives of Civil Engineering; 2019, 65, 2; 209-222
    1230-2945
    Pojawia się w:
    Archives of Civil Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Intelligent System in the Context of Business Process Modelling
    Autorzy:
    Yaremko, Svetlana A.
    Kuzmina, Elena M.
    Savina, Nataliia B.
    Gromaszek, Konrad
    Yeraliyeva, Bakhyt
    Borankulova, Gauhar
    Powiązania:
    https://bibliotekanauki.pl/articles/1844622.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    business process
    automation
    simulation modelling
    intelligent system
    expert system
    intelligence analysis
    forecasting
    Opis:
    The article deals with the features and characteristics of intelligent systems for modelling business processes. Their classification was made and criteria for comparison were developed. According to the comparative analysis of existing expert systems for intelligent analysis, a reasonable choice of system for modelling business processes of a particular enterprise has been carried out. In general, it was found that the introduction of intelligent systems for modelling business processes of the enterprise and forecasting its activities for future allows management of the company to obtain relevant and necessary information for the adoption of effective management decisions and the development of a strategic plan.
    Źródło:
    International Journal of Electronics and Telecommunications; 2021, 67, 2; 163-168
    2300-1933
    Pojawia się w:
    International Journal of Electronics and Telecommunications
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    DTA Thermal Analysis of Alloys from Nickel-Rich Part of Ni-Al-Cr System
    Autorzy:
    Maciąg, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/351762.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Ni-Al-Cr system
    order-disorder
    DTA analysis
    Opis:
    Thermal analysis allows for determination of temperature specific for the beginning and the end of phase transitions occurring in studied samples. In this paper results obtained from DTA (Differential Thermal Analysis) of alloys of chemical composition referring to nickel-rich part of Ni-Al-Cr system, specifically from section Ni75Al25÷Ni65Cr35 are presented. Those alloys are based on intermetallic phase Ni3 Al. Referring to measurements obtained during heating and cooling, characteristic peaks related to occurrence of phase transition of order-disorder type were noted as well as melting and solidification temperature of alloys was determined. Results of thermal analysis DTA of studied range were compared with results obtained for section Ni75Al25÷Ni75Cr25 and Ni75Al25÷Ni87Cr13, additionally results of measurements performed on high-temperature solution calorimeter were collated. Both methods presented good compatibility.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 2; 981-986
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Improvement of damping characteristics and index evaluation of a wind-PV-thermal-bundled power transmission system by combining PSS and SSSC
    Autorzy:
    He, Ping
    Wu, Xinxin
    Li, Congshan
    Zheng, Mingming
    Li, Zhao
    Powiązania:
    https://bibliotekanauki.pl/articles/140453.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    damping characteristics
    eigenvalue analysis
    power system stabilizer
    wind-PV-thermal-bundled power system
    Opis:
    The grid integration of large-scale wind and solar energy affects the power flow of wind-PV-thermal-bundled power transmission systems and may introduce an unpredicted threat to the power system’s small signal stability. Meanwhile, a power system stabilizer (PSS) and static synchronous series compensator (SSSC) play an important role in improving the static and dynamic stability of the system. Based on this scenario and in view of the actual engineering requirements, the framework of wind-PV-thermal-bundled power transmitted by an AC/DC system with the PSS and SSSC is established considering the fluctuation of wind and photovoltaic power output and the characteristics of the PSS and SSSC. Afterwards, the situation model is constructed in the IEEE 2-area 4-unit system, and the influence of the PSS and SSSC on the system stability under different operating conditions is analyzed in detail through eigenvalue analysis and time-domain simulation. Finally, an index named the gain rate is defined to describe the improvement of the stability limitations of various wind-PV-thermal operating conditions with the PSS and SSSC. The results indicate (K) that the damping characteristics, dynamic stability and stability limitations for various wind-PV-thermal operating conditions of the wind-PV-thermal-bundled power transmission system can be significantly improved by the interaction of the PSS and SSSC.
    Źródło:
    Archives of Electrical Engineering; 2020, 69, 3; 705-721
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Ocena jakości metalurgicznej żeliwa sferoidalnego w oparciu o analizę termiczną ATAS
    Rating Metallurgical Quality Ductile Iron Based on Thermal Analysis ATAS
    Autorzy:
    Ronduda, M.
    Zaczyński, A.
    Schmalenberg, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/382827.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    analiza termiczna
    żeliwo sferoidalne
    system ATAS
    thermal analysis
    spheroidal cast iron
    ATAS system
    Opis:
    Przedstawiono dwie metody oceny stabilności jakości metalurgicznej ciekłego metalu podczas przetrzymywania stopu w piecu, sferoidyzacji i modyfikacji. Powszechnie stosowane prowadzenie procesu metalurgicznego bazuje się na doborze tworzywa o określonym równoważniku węglowym CE z wykorzystaniem wyników analizy spektralnej składu chemicznego stopu. Wprowadzenie analizy termicznej pozwoliło na procesowy monitoring on-line wykorzystujący aktywny równoważnik węglowy ACEL. Zastosowana analiza termiczna (system ATAS) umożliwiła uzyskanie większej stabilności procesowej otrzymywania odlewów z żeliwa sferoidalnego bez porowatości skurczowej.
    There were presented two methods to estimate the liquid cast iron metallurgical quality stability, during casting alloy’s furnace processing, spheroidization and modification. Commonly used metallurgical process handling was based on choice of the material with specified carbon equivalent (CE), basing on spectroanalysis. On the other hand thermoanalysis has enabled the „on-line” process monitoring, with the use of active carbon equivalent ACEL. Thermoanalysis applied (the ATAS system) allowed to achieve better process stability of nodular cast iron and castings without shrinkage porosity.
    Źródło:
    Archives of Foundry Engineering; 2015, 15, 4 spec.; 103-108
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Computer system for identification of material models on the basis of plastometric tests
    System komputerowy do identyfikacji modeli materiałowych na podstawie testów plastometrycznych
    Autorzy:
    Rauch, L.
    Sztangret, L
    Pietrzyk, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/351404.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    inverse analysis
    metamodel
    computer system
    plastometric test
    analiza odwrotna
    system komputerowy
    test plastometryczny
    Opis:
    The paper describes the hybrid computer system dedicated to identification of models of materials subjected to thermomechanical processing. The functionalities of the system consist of plastometric tests data processing and application of the inverse analysis. The latter functionality is realized unconventionally, instead of the finite element method the metamodel is implemented using artificial neural network. The metamodels, used for simulations of the plastometric tests, are imported to the proposed computer system as external plugins, what guarantees flexibility and possibility of further development. On the other hand, application of rich optimization libraries assures the best possible solution of the problem. Basic principles of the inverse analysis with metamodels and mentioned optimization procedures are described in the paper. Selected examples of identification of models for various metallic materials recapitulate the paper.
    Artykuł przedstawia system komputerowy dedykowany identyfikacji modeli materiałów poddanych obróbce cieplnomechanicznej. Funkcjonalność systemu obejmuje przetwarzanie danych pomiarowych oraz analizę odwrotną. W przeciwieństwie do rozwiązań konwencjonalnych opartych o metodę elementów skończonych, podstawę rozwiązania stanowi metamodel do symulacji prób doświadczalnych wykonywanych dla identyfikacji modeli materiałów. Metamodele zrealizowane z użyciem sztucznych sieci neuronowych są importowane do systemu jako tzw. wtyczki, co zapewnia elastyczność i mozliwość rozwoju rozwiązania. Ponadto, wykorzystanie bogatych bibliotek metod optymalizacji zapewnia uzyskanie najlepszego z możliwych rozwiązań. Podstawowe zagadnienia analizy odwrotnej z użyciem metamodeli oraz wspomnianych metod optymalizacji opisane zostały w niniejszym artykule. Przedstawiona została również architektura stworzonego systemu komputerowego oraz przykłady jego wykorzystania do identyfikacji parametrów modeli wybranych materiałów metalicznych.
    Źródło:
    Archives of Metallurgy and Materials; 2013, 58, 3; 737-743
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Does lean practices implementation impact on company performance? A meta-analytical research
    Autorzy:
    Gonçalves, Telma I. G.
    Sousa, Paulo S. A.
    Moreira, Maria R. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/407127.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    lean manufacturing
    performance evaluation
    meta-analysis
    manufacturing system
    company
    Opis:
    Studies linking the use of lean practices to company performance have been increasing as markets are becoming more competitive and companies are eager for reducing waste and therefore implementing the Lean Management (LM) philosophy to improve performance. However, results from these studies have found various and different impacts and some light is needed. Extant literature was reviewed and, to achieve the research objective, a metaanalysis of correlations was carried out. The obtained results suggest a positive relationship between some lean practices and performance measures. Furthermore, the presence of moderators influencing the relationship between lean practices and performance outcomes is highlighted in our results. To our best knowledge, this is the first research that proposes a comparison of results from primary studies on Lean implementation, by analysing the linear relationship between lean practices and enterprise performance. It fills this gap and therefore represents an important contribution.
    Źródło:
    Management and Production Engineering Review; 2019, 10, 4; 11-24
    2080-8208
    2082-1344
    Pojawia się w:
    Management and Production Engineering Review
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis and comparison of the stability of discrete-time and continuous-time linear systems
    Autorzy:
    Kaczorek, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/229420.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    analysis
    comparison
    stability
    discrete-time
    continuous-time
    linear system
    Opis:
    The asymptotic stability of discrete-time and continuous-time linear systems described by the equations xi+1 = Ākxi and x(t) = Akx(t) for k being integers and rational numbers is addressed. Necessary and sufficient conditions for the asymptotic stability of the systems are established. It is shown that: 1) the asymptotic stability of discrete-time systems depends only on the modules of the eigenvalues of matrix Āk and of the continuous-time systems depends only on phases of the eigenvalues of the matrix Ak, 2) the discrete-time systems are asymptotically stable for all admissible values of the discretization step if and only if the continuous-time systems are asymptotically stable, 3) the upper bound of the discretization step depends on the eigenvalues of the matrix A.
    Źródło:
    Archives of Control Sciences; 2016, 26, 4; 551-563
    1230-2384
    Pojawia się w:
    Archives of Control Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Construction of an Expert System Based on Fuzzy Logic for Diagnosis of Analog Electronic Circuits
    Autorzy:
    Grzechca, D. E.
    Powiązania:
    https://bibliotekanauki.pl/articles/226616.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    analog circuits fault diagnosis
    analog system testing
    fuzzy set theory
    expert system
    sensitivity analysis
    Opis:
    The paper presents construction of the fuzzy logic system to analog circuits parametric fault diagnosis. The classical dictionary construction is replaced by fuzzy rule system. The first part refers to analog fault diagnosis, its techniques, approaches and goals. It clarifies common strategy and define differences between detecting, locating and identifying a fault in analog electronic circuit. The second part is focused on a creation of fuzzy rule expert system with use of sensitivity functions and known circuit topology. To detect, locate and identify a faulty element in a circuit the sensitivity matrix is used. The advantage of the method is its utilization in all, AC, DC and time domain. The fuzzy system, like the classical fault dictionary, can detect and locate single catastrophic faults and, on the contrary to the classical one, it also detects and locates parametric faults. Moreover, it allows identification of these faults, such that sign of the faulty parameter deviation is designated. The method has deterministic character as well as it can be applied on the verification and production stage.
    Źródło:
    International Journal of Electronics and Telecommunications; 2015, 61, 1; 77-82
    2300-1933
    Pojawia się w:
    International Journal of Electronics and Telecommunications
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fusing the electromagnetic articulograph, high-speed video cameras and a 16-channel microphone array for speech analysis
    Autorzy:
    Mik, Ł.
    Lorenc, A.
    Król, D.
    Wielgat, R.
    Święciński, R.
    Jędryka, R.
    Powiązania:
    https://bibliotekanauki.pl/articles/200263.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    electromagnetic articulography
    microphone array
    vision system
    speech analysis
    artykulograf elektromagnetyczny
    system wizyjny
    analiza mowy
    Opis:
    Electromagnetic articulography (EMA) is one of the instrumental phonetic research methods used for recording and assessing articulatory movements. Usually, articulographic data are analysed together with standard audio recordings. This paper, however, demonstrates how coupling the articulograph with devices providing other types of information may be used in more advanced speech research. A novel measurement system is presented that consists of the AG 500 electromagnetic articulograph, a 16-channel microphone array with a dedicated audio recorder and a video module consisting of 3 high-speed cameras. It is argued that synchronization of all these devices allows for comparative analyses of results obtained with the three components. To complement the description of the system, the article presents innovative data analysis techniques developed by the authors as well as preliminary results of the system’s accuracy.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2018, 66, 3; 257-266
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Development of QoS Methods in the Information Networks with Fractal Traffic
    Autorzy:
    Daradkeh, Y. I.
    Kirichenko, L.
    Radivilova, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/227166.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    communication system traffic
    fractals
    quality of service
    queueing analysis
    routing
    Opis:
    The paper discusses actual task of ensuring the quality of services in information networks with fractal traffic. The generalized approach to traffic management and quality of service based on the account of multifractal properties of the network traffic is proposed. To describe the multifractal traffic properties, it is proposed to use the Hurst exponent, the range of generalized Hurst exponent and coefficient of variation. Methods of preventing of network overload in communication node, routing cost calculation and load balancing, which based on fractal properties of traffic are presented. The results of simulation have shown that the joint use of the proposed methods can significantly improve the quality of service network.
    Źródło:
    International Journal of Electronics and Telecommunications; 2018, 64, 1; 27-32
    2300-1933
    Pojawia się w:
    International Journal of Electronics and Telecommunications
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Location of generating units most affecting the angular stability of the power system based on the analysis of instantaneous power waveforms
    Autorzy:
    Pruski, Piotr
    Paszek, Stefan
    Powiązania:
    https://bibliotekanauki.pl/articles/229521.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    power system
    modal analysis
    electromechanical eigenvalues
    transient states
    angular stability
    Opis:
    In the paper, the results of investigations on the location of generating units most affecting the angular stability of a large power system (PS) are presented. For their location, the eigenvalues of the PS model state matrix associated with electromechanical phenomena (electromechanical eigenvalues) were used. The eigenvalues were calculated on the basis of the analysis of the disturbance waveforms of instantaneous power of the generating units operating in the PS. The used method of calculating eigenvalues consists in approximation of the disturbance waveforms of generating units by the waveforms being the superposition of modal components. The parameters of these components depend on the sought eigenvalues and their participation factors. The objective function was defined as the mean square error between the approximated and approximating waveforms. To minimize it, a hybrid algorithm, being a combination of genetic and gradient algorithms, was used. In the instantaneous power waveforms of generating units most affecting the PS angular stability, the least damped or undamped modal components dominate. They are related to eigenvalues with the largest values of real parts. The impact of individual modal components on the disturbance waveforms of subsequent generating units was determined with the use of participation factors and correlation coefficients of electromechanical eigenvalues.
    Źródło:
    Archives of Control Sciences; 2020, 30, 2; 273-293
    1230-2384
    Pojawia się w:
    Archives of Control Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Numerical simulation of subsidence caused by roadway system
    Symulacja numeryczna deformacji powierzchni spowodowanych eksploatacją chodnikową
    Autorzy:
    Polanin, Piotr
    Kowalski, Andrzej
    Walentek, Andrzej
    Powiązania:
    https://bibliotekanauki.pl/articles/220269.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    eksploatacja górnicza
    system chodnikowy
    modelowanie numeryczne
    analiza wsteczna
    mining
    roadway system
    numerical modeling
    back analysis
    Opis:
    Exploitation of hard coal seams by roadway system is applied by two coal mines in southern Poland in Upper Silesian Basin. It is a secondary mining exploitation carries out in safety pillars of urban areas and shafts within mining areas of closed coal mines. Roadway system is the excavation process of gateways which are made in parallel order leaving coal pillars between them. An optimal width of coal pillar makes roadway stable and reduces subsidence of terrain surface. The article presents results of subsidence simulation caused by partial extraction using empirical and numerical methods on the example of one exploitation field of “Siltech” coal mine. The asymptotic state of subsidence was considered after mining ceased in the study area. In order to simulate of subsidence, numerical model of rock mass and model of Knothe-Budryk theory were calibrated. Simulation of vertical displacements in numerical method was carried out using RS3 program by Rocscience based on finite element method. The assumption was made that model of rock mass is transversely isotropic medium, in which panels were designed according to order of extraction of coal seams. The results of empirical and numerical methods were compared with measured values of subsidence at benchmarks along drawn lines (subsidence profiles).
    Eksploatacja złoża węgla kamiennego systemem chodnikowym jest stosowana w Polsce w Górnośląskim Zagłębiu Węglowym przez dwie kopalnie. Jest to eksploatacja wtórna prowadzona na obszarach górniczych zlikwidowanych kopalń w filarach ochronnych szybów i zabudowy powierzchni. Proces technologiczny polega na drążeniu równoległych do siebie chodników w granicach pól eksploatacyjnych. Pomiędzy wyrobiskami pozostawiane są filary węglowe o odpowiedniej szerokości w celu zapewnienia ich stateczność i minimalizacji deformacji powierzchni terenu. W artykule przedstawiono wyniki symulacji obniżeń terenu spowodowanych eksploatacją częściową przy wykorzystaniu metody empirycznej i modelowania numerycznego na przykładzie jednego pola eksploatacyjnego kopalni „Siltech”. Analiza obejmowała asymptotyczny stan deformacji terenu po zakończonej eksploatacji w tym rejonie. W celu odwzorowania obniżeń terenu wykonano kalibrację numerycznego modelu górotworu i teorii Knothego-Budryka. Symulację obniżeń powierzchni terenu metodą numeryczną (MES) wykonano programem RS3 firmy Rocscience. Założono, że model górotworu jest ośrodkiem transwersalnie izotropowym, w którym odtworzono eksploatację systemem chodnikowym zgodnie z kolejnością wybierania pokładów. Dla wytypowanych punktów obserwacyjnych tworzących ciąg linii porównano obliczone obniżenia metodą empiryczna i numeryczną z wartościami zmierzonymi w terenie.
    Źródło:
    Archives of Mining Sciences; 2019, 64, 2; 385-397
    0860-7001
    Pojawia się w:
    Archives of Mining Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Probabilistic elements in analysis of performance of multiprocessor systems
    Autorzy:
    Taborek, K.
    Hrynkiewicz, E.
    Powiązania:
    https://bibliotekanauki.pl/articles/201505.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    arbitration circuit
    multiprocessor system
    performance analysis
    queueing model
    arbitraż
    system wieloprocesorowy
    analiza wydajności
    model kolejkowy
    Opis:
    The paper presents important probabilistic elements that should be taken into consideration in the analysis of performance of classical multiprocessor systems. These elements represent the following quantities: modified arrival rate for processor requests and a few probabilities, which determine the frequency of certain events when a multiprocessor system is working. There are four peculiar events: service of another job, existence of the queue, a processor request while the given task is waiting into the queue and the return of another task into the queue while the given task is waiting in the queue. The first three events happen more often when a system consists of less number of processors, whereas the fourth event happens more often when more processors work in a system. Including (or not) the probabilities of these events to the analysis of performance of multiprocessor systems exerts its much influence on the precision of computations. All the mentioned quantities were described in detail. Formulas for these quantities were derived. Examples of applications of the formulas to the prediction of performance of various multiprocessor systems were presented.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2014, 62, 4; 765-771
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Modeling and Designing Acoustical Conditions of the Interior – Case Study
    Autorzy:
    Kostek, B.
    Laskowski, S.
    Mizgier, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/176652.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    acoustic field analysis
    acoustic field modeling
    acoustic conditions measurements
    acoustic conditions analysis
    sound reinforcement system design
    Opis:
    The primary aim of this research study was to model acoustic conditions of the Courtyard of the Gdańsk University of Technology Main Building, and then to design a sound reinforcement system for this interior. First, results of measurements of the parameters of the acoustic field are presented. Then, the comparison between measured and predicted values using the ODEON program is shown. Collected data indicate a long reverberation time which results in poor speech intelligibility. Then, a thorough analysis is perform to improve the acoustic properties of the model of the interior investigated. On the basis of the improved acoustic model two options of a sound reinforcement system for this interior are proposed, and then analyzed. After applying sound absorbing material it was noted that the predicted speech intelligibility increased from bad/poor rating to good category.
    Źródło:
    Archives of Acoustics; 2016, 41, 3; 473-484
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Efficient choice of parameters on delta-reachability bounded hybrid systems
    Autorzy:
    Rocha, Eugénio Miguel Alexandre
    Murillo, Kelly Patricia
    Powiązania:
    https://bibliotekanauki.pl/articles/2083460.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    bounded hybrid system
    safety property
    delta-reachability
    multidirectional efficiency analysis
    Opis:
    Hybrid systems (HS) are roughly described as a set of discrete state transitions and continuous dynamics modeled by differential equations. Parametric HS may be constructed by having parameters on the differential equations, initial conditions, jump conditions, or a combination of the previous ones. In real applications, the best solution is obtained by a set of metrics functional over the set of solutions generated from a finite set of parameters. This paper examines the choice of parameters on delta-reachability bounded hybrid systems. We present an efficient model based on the tool pHL-MT to benchmark the HS solutions (based on dReach), and a non-parametric frontier analysis approach, relying on multidirectional efficiency analysis (MEA). Three numerical examples of epidemic models with variable growth infectivity are presented, namely: when the variable of infected individuals oscillates around some endemic (non-autonomous) equilibrium; when there is an asymptotically stable non-trivial attractor; and in the presence of bump functions.
    Źródło:
    Archives of Control Sciences; 2021, 31, 4; 781-794
    1230-2384
    Pojawia się w:
    Archives of Control Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Dynamic interactions stability analysis of hybrid renewable energy system with SSSC
    Autorzy:
    He, Ping
    Qi, Pan
    Ji, Yuqi
    Li, Zhao
    Powiązania:
    https://bibliotekanauki.pl/articles/1841302.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    damping characteristics
    dynamic interaction analysis
    eigenvalue analysis
    hybrid renewable energy system
    SSSC
    charakterystyka tłumienia
    dynamiczna analiza interakcji
    analiza wartości własnej
    hybrydowy system energii odnawialnej
    Opis:
    The static series synchronous compensator (SSSC) has demonstrated its capability in providing voltage support and improving power system stability. The objective of this paper is to analyze the dynamic interaction stability mechanism of a hybrid renewable energy system connected with doubly-fed induction generators (DFIGs) and solid oxide fuel cell (SOFC) energy with the SSSC. For this purpose, a linearized mathematical model of this modified hybrid single-machine infinite-bus (SMIB) power system is developed to analyze the physical mechanism of the SSSC in suppressing oscillations and the influence on the dynamic stability characteristics of synchronization. Typical impacting factors such as the series compensation level, the SOFC penetration and tie-line power are considered in the SMIB and two-area systems. The impact of dynamic interactions on enhancing damping characteristics and improving transient performance of the studied systems is demonstrated using eigenvalue analysis and dynamic time-domain simulations, which validates the validity of the proposed physical mechanism simultaneously.
    Źródło:
    Archives of Electrical Engineering; 2021, 70, 2; 445-462
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Methods for calculating the efficiency of logistics centres
    Metody obliczania efektywności Centrów Logistycznych
    Autorzy:
    Brdulak, J.
    Zakrzewski, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/223993.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    logistics centres
    organizational analysis
    economic efficiency
    transport system
    system transportowy
    Centrum Logistyczne
    analiza organizacyjna
    efektywność ekonomiczna
    Opis:
    Changes in the organization of the transport system, such as building a logistics centre, bring them uncertainties linked with the risk of investments failure. One of the first steps of creating such a logistics centre is carrying out a thorough economic analysis. Localization and organizational analysis and then the assessment of the functioning of the future centre is possible mainly thanks to the economic effectiveness calculation, which takes into account the expenditure, the operating costs, and benefits of creating a logistics centre in a selected place and gives the answer concerning the reasonableness of organizing such a centre. The article describes various types of the economic effectiveness calculations. As a result of the analysis performed a formula has been suggested, which can be used in the case of estimating the rationality of organizing a sample Logistic Centre consisting of four infrastructural elements. All of the described above simple and complex methods for calculating economic efficiency are the starting point for a discussion on the use of REE calculation for Logistic Centre in Southern Podlasie.
    Zmiany w organizacji systemu transportowego, takie jak budowa centrum logistycznego, powodują niepewności związane z ryzykiem niepowodzenia inwestycji. Jednym z pierwszych etapów tworzenia takiego centrum logistycznego jest przeprowadzenie dogłębnej analizy ekonomicznej. Lokalizacja i analiza organizacyjna, a następnie ocena funkcjonowania przyszłego centrum jest możliwa głównie dzięki obliczaniu efektywności ekonomicznej, która uwzględnia wydatki, koszty eksploatacji i korzyści z utworzenia centrum logistycznego w wybranym miejscu i daje odpowiedź dotyczącą zasadności organizowania takiego centrum. W artykule opisano różne rodzaje obliczeń efektywności ekonomicznej. Jako wynik przeprowadzonej analizy sugerowano wzorzec, który może być stosowany w przypadku szacowania racjonalność organizowania próbnego Centrum Logistycznego składającego się z czterech elementów infrastruktury. Wszystkie opisane powyżej proste i złożone metody obliczania efektywności ekonomicznej są punktem wyjścia do dyskusji na temat stosowania obliczeń REE dla Centrum Logistycznego na Południowym Podlasiu.
    Źródło:
    Archives of Transport; 2013, 27-28, 3-4; 25-43
    0866-9546
    2300-8830
    Pojawia się w:
    Archives of Transport
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A thermo-hydraulic tool for automatic virtual hazop evaluation
    Autorzy:
    Pugi, L.
    Conti, R.
    Rindi, A.
    Rossin, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/220567.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    RT code prototyping
    lube oil console
    rotating machine HazOp analysis
    transient behaviour analysis
    Plant-Control System interaction
    Opis:
    Development of complex lubrication systems in the Oil&Gas industry has reached high levels of competitiveness in terms of requested performances and reliability. In particular, the use of HazOp (acronym of Hazard and Operability) analysis represents a decisive factor to evaluate safety and reliability of plants. The HazOp analysis is a structured and systematic examination of a planned or existing operation in order to identify and evaluate problems that may represent risks to personnel or equipment. In particular, P&ID schemes (acronym of Piping and Instrument Diagram according to regulation in force ISO 14617) are used to evaluate the design of the plant in order to increase its safety and reliability in different operating conditions. The use of a simulation tool can drastically increase speed, efficiency and reliability of the design process. In this work, a tool, called TTH lib (acronym of Transient Thermal Hydraulic Library) for the 1-D simulation of thermal hydraulic plants is presented. The proposed tool is applied to the analysis of safety relevant components of compressor and pumping units, such as lubrication circuits. Opposed to the known commercial products, TTH lib has been customized in order to ease simulation of complex interactions with digital logic components and plant controllers including their sensors and measurement systems. In particular, the proposed tool is optimized for fixed step execution and fast prototyping of Real Time code both for testing and production purposes. TTH lib can be used as a standard SimScape-Simulink library of components optimized and specifically designed in accordance with the P&ID definitions. Finally, an automatic code generation procedure has been developed, so TTH simulation models can be directly assembled from the P&ID schemes and technical documentation including detailed informations of sensor and measurement system.
    Źródło:
    Metrology and Measurement Systems; 2014, 21, 4; 631-648
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Uncertainty analysis of measuring system for instantaneous power research
    Autorzy:
    Dzwonkowski, A.
    Swędrowski, L.
    Powiązania:
    https://bibliotekanauki.pl/articles/221896.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    measuring system
    metrological analysis
    power measurements
    measurement uncertainty
    induction motor diagnostics
    Opis:
    The electrical power drawn by an induction motor is distorted in case of appearance of a certain type of failures. Under spectral analysis of the instantaneous power one obtains the components which are connected with definite types of damage. An analysis of the amplitudes and frequencies of the components allows to recognize the type of fault. The paper presents a metrological analysis of the measurement system used for diagnosis of induction motor bearings, based on the analysis of the instantaneous power. This system was implemented as a set of devices with dedicated software installed on a PC. A number of measurements for uncertainty estimation was carried out. The results of the measurements are presented in the paper. The results of the aforementioned analysis helped to determine the measurement uncertainty which can be expected during bearing diagnostic measurements, by the method relying on measurement and analysis of the instantaneous power of an induction machine.
    Źródło:
    Metrology and Measurement Systems; 2012, 19, 3; 573-582
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Inter-harmonic parameter identification method based on transform with local maximum spectrum
    Autorzy:
    Sun, Lin
    Song, Jing
    Jin, Yan
    Powiązania:
    https://bibliotekanauki.pl/articles/2042793.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    inter-harmonic
    parameter identification
    power system
    synchrosqueezed transform
    time-frequency analysis
    Opis:
    In order to improve the detection accuracy of harmonics/inter-harmonics in power systems, a new method of harmonic/inter-harmonic detection based on synchrosqueezed transform and the Hilbert operator based on local spectrum maximum is proposed. Firstly, the spectrum of inter-harmonic signals is obtained through short-time Fourier transform, and the local maximum value of the spectrum in the frequency direction is detected. Then, based on the maximum frequency of the spectrum, a new frequency redistribution operator and synchronous extraction operator are constructed. It combines the operators with ridge detection for the decomposition of harmonic/inter-harmonic signals, so as to obtain a series of intrinsic mode function (IMF) components. Finally, the instantaneous amplitude and frequency of the IMF components is obtained by using the Hilbert operator. Meanwhile, according to the instantaneous frequency mutation point in the spectrum, the starting and ending time of transient harmonics/inter-harmonics is located accurately. Based on a low signal-to-noise ratio (SNR), the wavelet packet method (WP), Hilbert Marginal Spectrum method (HMS), synchrosqueezing wavelet transform method (SST), the Hybrid SST method (HSST), enhanced empirical wavelet transform (EEWT) and the proposed method are used to identify the harmonic/inter-harmonic parameters, respectively. The experimental results show that the proposed LMSST method can effectively separate the steady-state and transient harmonic/inter-harmonic signals, and has higher detection accuracy and better noise robustness.
    Źródło:
    Archives of Electrical Engineering; 2022, 71, 1; 189-209
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Contribution of symbolic generation to the sensitivity analysis of automotive suspension parameters
    Wykorzystanie symbolicznego generowania równań w analizie wrażliwości zawieszenia samochodowego na zmiany parametrów
    Autorzy:
    Poncelet, A.
    Collard, J. F.
    Fisette, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/139470.pdf
    Data publikacji:
    2010
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    system wieloczłonowy
    analiza wrażliwości
    generowanie symboliczne
    dynamika pojazdu
    multibody system
    sensitivity analysis
    symbolic generation
    vehicle dynamics
    Opis:
    The purpose of the present research relates to the sensitivity analysis of road vehicle comfort and handling performances with respect to suspension technological parameters. The envisaged suspension being of semi-active nature, this implies first to consider an hybrid modeling approach consisting of a 3D multibody model of the full car - an Audi A6 in our case - coupled with the electro-hydraulic model of the suspension dampers. Concerning parameter sensitivitie, the goal is to capture them for themselves - and not necessarily for optimization purpose - because their knowledge is of a great interest for the damper manufacturer. An important issue of the research is to consider objective functions which are based on complete time integrations along a given trajectory, the goal being - for instance - to quantify the sensitivity of the carbody rms acceleration (comfort) or of the vehicle overturning character (handling) with respect to suspension parameters. On one hand, the accuracy of the various partial derivatives computation can be greatly enhanced thanks to the symbolic capabilities of our ROBOTRAN multibody program. On the other hand, the computational efficiency of the process also takes advantage of the recursive formulation of the multibody equations of motion which must be time integrated with respect to both the generalized coordinates and their partial derivatives in case of the so-called direct method underlying sensitivity analysis.
    Cel przedstawionych badań jest związany z analizą wrażliwościową wpływu, jaki na komfort jazdy i właściwości jezdne pojazdu drogowego mają parametry technologiczne jego zawieszenia. Przewiduje się, że zawieszenie będzie miało charakter półaktywny, co implikuje podejście polegające na modelowaniu hybrydowym, w którym wykorzystuje się trójwymiarowy model całego samochodu - w konkretnym przypadku jest to Audi A6 - w połączeniu z elektro-hydraulicznym modelem amortyzatorów zawieszenia. Wrażliwość modelu bada się, by określić wartości parametrów - a nie w celach optymalizacyjnych - gdyż znajomość tych wielkości jest ogromnie interesująca dla producentów amortyzatorów. Ważną kwestią w tych badaniach jest przyjęcie funkcji celu, które oparte są na całkowaniu pewnych wielkości podczas całego czasu realizacji zadanej trajektorii. Celem może być - na przykład - określenie wrażliwości średniokwadratowego przyspieszenia nadwozia (komfort) lub charakterystyki przewracania się samochodu (własności trakcyjne) na zmiany parametrów zawieszenia. Z jednej strony, dokładność obliczeń różnych pochodnych cząstkowych może być znakomicie zwiększona dzięki możliwościom programu do symulacji układów wieloczłonowych ROBOTRAN, który wykorzystuje postać symboliczną równań. Z drugiej strony, korzystny dla wydajności procesu obliczeniowego jest również fakt. że równania ruchu układu wieloczłonowego są sformułowane w postaci rekursywnej. W przypadku tak zwanej metody bezpośredniej, która leży u podstaw analizy wrażliwości, równania te muszą być całkowane w dziedzinie czasu względem zarówno współrzędnych uogólnionych jak i ich pochodnych cząstkowych.
    Źródło:
    Archive of Mechanical Engineering; 2010, LVII, 2; 207-225
    0004-0738
    Pojawia się w:
    Archive of Mechanical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    P1-TS fuzzy scheduling control system design using local pole placement and interval analysis
    Autorzy:
    Smoczek, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/199816.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    P1-TS fuzzy system
    scheduling control
    LPV discrete-time system
    local pole placement
    interval analysis
    Opis:
    The linear parameter-varying (LPV) discrete-time model based design of a fuzzy scheduling control scheme is developed through incorporating the advantages of P1-TS theory, and applying the local pole placement method and interval analysis of closed-loop system polynomial coefficients. The synthesis of fuzzy scheduling control scheme is proposed in the form of iterative procedure, which enables to find the appropriate number of intervals of a fuzzy interpolator ensuring that a family of local linear controllers places closed-loop polynomial coefficients within a desired range. The computational complexity of multidimensional fuzzy scheduling control scheme synthesis is reduced using a fundamental matrix method and recursive procedure for fuzzy rule-based interpretation. The usability of the proposed method is illustrated by an implementation example and experimental results obtained on a laboratory scaled overhead crane.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2014, 62, 3; 455-464
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Superficial and systemic diagnosis of family
    Autorzy:
    Świętochowski, Waldemar
    Powiązania:
    https://bibliotekanauki.pl/articles/430197.pdf
    Data publikacji:
    2010
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    assessment of family system
    systemic traits
    factor analysis in family research
    Opis:
    The distinction between two types of diagnosis of family was inspired by the concept of surface and source features of personality by R.B. Cattell. By means of existing psychological questionnaires we can only know the surface of consciously available mental phenomena. The same is true in the diagnosis of family. The McMaster model of family, systemic in its assumptions, developed research tools giving access only to the surface of the phenomena. Although they are divided into certain thematic categories they do not reveal what is really important in the family system. In this article, the author, after a detailed discussion of one of the tests based on the McMaster theoretical model, is attempting to identify the source features (here: unavailable for conscious cognition) of the family, hereinafter called systemic traits. In this research the exploration factor analysis was used. Three perspectives of the opinion of the family were maintained (like in the Family Assessment Measure). Factor analysis allowed identification of three factors for each perspective of the family assessment. Confirmative analysis proved a satisfactory match (using RMSEA, GFI and AGFI statistics). The accuracy of the identified systemic model was then tested by a confirmation study (confirmative factor analysis using Amos from SPSS). The authors also prepared a provisional questionnaire for measuring these systemic traits of the family. The tool proved to be promising and the work worth continuing. Incidentally, it turned out that the characteristics of the family system are relatively independent of personality traits of family members.
    Źródło:
    Polish Psychological Bulletin; 2010, 41, 3; 113-121
    0079-2993
    Pojawia się w:
    Polish Psychological Bulletin
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Decision Support System for Epileptogenic Zone Location During Brain Resection
    Autorzy:
    Kołodziej, M.
    Majkowski, A.
    Rak, R. J.
    Rysz, A.
    Marchel, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/221787.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ECoG
    iEEG
    electrocorticography
    epileptogenic zone
    signal analysis
    expert system
    neural network
    Opis:
    This paper presents a system for locating the epileptogenic zone (EZ) using an automated analysis of electrocorticography (ECoG) signal recorded with 20 electrodes placed on the brain surface. The developed system enables automatic determination of places where anomalies connected with epilepsy are observed. The developed algorithm was tested on signals recorded for 33 patients who, after a prior neurological analysis, underwent the brain resection surgery. The results obtained with the algorithm were compared with those of medical analyses performed by the neurologist. The proposed system has a satisfactory accuracy – 87.8% – and can be used as a decision-supporting tool by the neurosurgeon during brain resection.
    Źródło:
    Metrology and Measurement Systems; 2018, 25, 1; 15-32
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Computation method for analysis of sliding faults in power systems
    Autorzy:
    Machowski, Jan
    Robak, Sylwester
    Powiązania:
    https://bibliotekanauki.pl/articles/2090700.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    power system
    short-circuit analysis
    sliding faults
    computation method
    system zasilania
    analiza zwarć
    wady ślizgowe
    metody obliczeniowe
    Opis:
    Short-circuit analysis is conducted based on the nodal impedance matrix, which is the inversion of the nodal admittance matrix. If analysis is conducted for sliding faults, then for each fault location four elements of the nodal admittance matrix are subject to changes and the calculation of the admittance matrix inversion needs to be repeated many times. For large-scale networks such an approach is time consuming and unsatisfactory. This paper proves that for each new fault location a new impedance matrix can be found without recalculation of the matrix inversion. It can be found by a simple extension of the initial nodal impedance matrix calculated once for the input model of the network. This paper derives formulas suitable for such an extension and presents a flowchart of the computational method. Numerical tests performed for a test power system confirm the validity and usefulness of the proposed method.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 1; e135841, 1--9
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Computation method for analysis of sliding faults in power systems
    Autorzy:
    Machowski, Jan
    Robak, Sylwester
    Powiązania:
    https://bibliotekanauki.pl/articles/2173554.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    power system
    short-circuit analysis
    sliding faults
    computation method
    system zasilania
    analiza zwarć
    wady ślizgowe
    metody obliczeniowe
    Opis:
    Short-circuit analysis is conducted based on the nodal impedance matrix, which is the inversion of the nodal admittance matrix. If analysis is conducted for sliding faults, then for each fault location four elements of the nodal admittance matrix are subject to changes and the calculation of the admittance matrix inversion needs to be repeated many times. For large-scale networks such an approach is time consuming and unsatisfactory. This paper proves that for each new fault location a new impedance matrix can be found without recalculation of the matrix inversion. It can be found by a simple extension of the initial nodal impedance matrix calculated once for the input model of the network. This paper derives formulas suitable for such an extension and presents a flowchart of the computational method. Numerical tests performed for a test power system confirm the validity and usefulness of the proposed method.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 1; art. no. e135841
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis of the accuracy of reconstruction of the geometry driving wheel of gear pump with application of CATIA system
    Analiza dokładności odwzorowania geometrii koła zębatego pompy zębatej z zastosowaniem systemu CATIA
    Autorzy:
    Zaborniak, M.
    Tofil-Kozdra, I.
    Powiązania:
    https://bibliotekanauki.pl/articles/176168.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    CAD
    cylindrical gears
    accuracy analysis
    system CAD
    walcowe koła zębate
    analiza dokładności
    Opis:
    Modern methods of design and manufacture of gears are based on Computer Aided Engineering Systems. This article presents one of the methods to analyze the accuracy of mapping geometry of the model of driving wheel of gear pump designed in CATIA v5 System. Comparison of the accuracy of mapping of the geometry of the hybrid model has been performed with the source model of gear (model .stl format).
    Podstawą nowoczesnych metod projektowania i wytwarzania kół zębatych są komputerowe systemy wspomagania prac inżynierskich. W pracy przedstawiono jedną z metod analizy dokładności odwzorowania geometrii modelu koła zębatego pompy zębatej w systemie CATIA v5. Przeprowadzono porównanie dokładności odwzorowania geometrii modelu hybrydowego ze źródłowym modelem koła zębatego (model .stl).
    Źródło:
    Advances in Manufacturing Science and Technology; 2015, 39, 2; 49-60
    0137-4478
    Pojawia się w:
    Advances in Manufacturing Science and Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Clamped Bar Model for the Sompoton Vibrator
    Autorzy:
    Wong, T. H.
    Dayou, J.
    Ngu, M. C. D.
    Hang, J. H. W.
    Liew, W. Z. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/176855.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    vibrator
    clamped bar
    single degree of freedom system
    exact analysis
    resonance frequency
    Opis:
    The sompoton is one of famous traditional musical instruments in Sabah. This instrument consists of several parts with the vibrator being the most important one. In this paper, the vibrator is modeled as a clamped bar with a uniformly distributed mass. By means of this model, the fundamental frequency is analyzed with the use of an equivalent single degree of freedom system (SDOF) and exact analysis. The vibrator is made of aluminum in different sizes and is excited using a constant air jet to obtain its fundamental resonance frequency. The fundamental frequency obtained from the experimental measurement is compared with the theoretical values calculated based on the equivalent SDOF and exact analysis theories. It is found that the exact analysis gives a closer value to the experimental results as compared to the SDOF system. Although both the experimental and theoretical results exhibit the same trend, they are different in magnitude. To overcome the differences in both theories, a correction factor is added to account for the production errors.
    Źródło:
    Archives of Acoustics; 2013, 38, 3; 425-432
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis of the accuracy of reconstruction of the geometry driving wheel of gear pump with application of CATIA system
    Analiza dokładności odwzorowania geometrii koła zębatego pompy zębatej z zastosowaniem systemu CATIA
    Autorzy:
    Zaborniak, M.
    Tofil-Kozdra, I.
    Powiązania:
    https://bibliotekanauki.pl/articles/176165.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    CAD
    cylindrical gear
    accuracy analysis
    system CAD
    koło zębate walcowe
    analiza dokładności
    Opis:
    Modern methods of design and manufacture of gears are based on Computer Aided Engineering Systems. This article presents one of the methods to analyze the accuracy of mapping geometry of the model of driving wheel of gear pump designed in CATIA v5 System. Comparison of the accuracy of mapping of the geometry of the hybrid model has been performed with the source model of gear (model .stl format).
    Podstawą nowoczesnych metod projektowania i procesu wytwarzania kół zębatych są komputerowe systemy wspomagania prac inżynierskich. W pracy przedstawiono jedną z metod analizy dokładności odwzorowania geometrii modelu koła zębatego pompy zębatej wykonanego w systemie CATIA v5. Przeprowadzono analizę i porównanie dokładności odwzorowania geometrii modelu hybrydowego oraz źródłowego modelu koła zębatego (model .stl).
    Źródło:
    Advances in Manufacturing Science and Technology; 2016, 40, 1; 55-66
    0137-4478
    Pojawia się w:
    Advances in Manufacturing Science and Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Spatial kinematic analysis of double 4-link coupler used in low-floor tram powertrains
    Przestrzenna analiza kinematyczna układu podwójnego sprzęgła 4-cięgłowego wykorzystywanego w tramwajach niskopodłogowych
    Autorzy:
    Maniowski, M.
    Czauderna, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/139591.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    kinematic analysis
    tram powertrain
    coupling system
    analiza kinematyczna
    układ napędowy tramwaju
    układ sprzęgłowy
    Opis:
    The paper presents kinematic characteristics of the double 4-link coupler system, used in actual powertrain of low-floor trams (NGT6-Kr). The spatial kinematic model of the couplings was formulated assuming ideal joints and rigid members. The constraints equations of the mechanism were solved iteratively and differentiated to obtain the Jacobian matrix. The mobility and singularity analysis of the coupler mechanism was performed on the basis of the Jacobian matrix. Kinematic characteristics of the single and double coupler system were analyzed for gross angular and linear axle displacements (misalignments), taking the advantage of the fully nonlinear model. The coupling system was evaluated based on criteria describing homokinetics, balancing and clearance demands, and angular displacements in the joints. These criteria were determined for different design parameters like: coupler proportions, platform shift and angle, middle shaft length.
    W pracy przestawiono charakterystyki kinematyczne układu napędowego z podwójnym sprzęgłem 4-cięgłowym, wykorzystywanym w tramwajach nisko-podłogowych (NGT6-Kr). Przestrzenny model kinematyczny sprzęgła został sformułowany zakładając idealne przeguby i sztywne ogniwa. Równania więzów mechanizmu rozwiązano iteracyjnie, a następnie zróżniczkowano w celu wyznaczenia macierzy jakobianowej mechanizmu. Macierz tą wykorzystano do analizy ruchliwości i osobliwości mechanizmu sprzęgła. Charakterystyki kinematyczne układu z pojedynczym i podwójnym sprzęgłem analizowano w zakresie dużych kątowych i liniowych przemieszczeń wałów układu napędowego. Układ sprzęgłowy oceniano w oparciu o następujące kryteria: homokinetyczność, wyrównoważenie, ograniczenie przestrzeni roboczej oraz dopuszczalne przemieszczenie w przegubach mechanizmu. Analiza parametryczna dotyczyła takich zmiennych konstrukcyjnych, jak: proporcje sprzęgła, przesunięcie i orientacja platform sprzęgieł, czy długość wału pośredniego.
    Źródło:
    Archive of Mechanical Engineering; 2016, LXIII, 1; 5-23
    0004-0738
    Pojawia się w:
    Archive of Mechanical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Design and evaluation of a needle tip measurement system based on binocular vision
    Autorzy:
    Lin, Yuyang
    Shi, Yunlai
    Zhang, Jun
    Wang, Fugang
    Sun, Haichao
    Powiązania:
    https://bibliotekanauki.pl/articles/220501.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    needle tip measurement
    binocular vision system
    measurement capability analysis
    non-contact optical positioning
    Opis:
    The precise location of the needle tip is critical in robot-assisted needle-based percutaneous interventions. An automatic needle tip measuring system based on binocular vision technology with the advantages of non-contact, excellent accuracy and high stability is designed and evaluated. First the measurement requirements of the prostate intervention robot are introduced. A laser interferometer is used as the reference for measuring the position of the needle tip whose relative position variation is described as the needle tip distance in the time domain. The parameters of the binocular cameras are obtained by Zhang’s calibration method. Then a robust needle tip extraction algorithm is specially designed to detect the pixel coordinates of the needle tip without installing the marked points. Once the binocular cameras have completed the stereo matching, the 3D coordinates of the needle tip are estimated. The measurement capability analysis (MCA) is used to evaluate the performance of the proposed system. The accuracy of the system can be controlled within 0.3621 mm. The agreement analysis is conducted by the Bland-Altman analysis, and the Pearson correlation coefficient is 0.999847. The P/T ratio value is 16.42% in the repeatability analysis. The results indicate that the accuracy and stability of the binocular vision needle tip measuring system are adequate to meet the requirement for the needle tip measurement in percutaneous interventions.
    Źródło:
    Metrology and Measurement Systems; 2020, 27, 3; 495-512
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Economic effectiveness evaluation of the free piston Stirling engine-based micro-combined heat and power unit in relation to classical systems
    Autorzy:
    Uchman, Wojciech
    Remiorz, Leszek
    Kotowicz, Janusz
    Powiązania:
    https://bibliotekanauki.pl/articles/240538.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    heating systems
    cost analysis
    stirling engine
    micro-cogeneration
    system ciepłowniczy
    analiza kosztów
    mikrokogeneracja
    Opis:
    In this article, a comparison of economic effectiveness of various heating systems dedicated to residential applications is presented: a natural gas-fueled micro-cogeneration (micro-combined heat and power – µCHP) unit based on a free-piston Stirling engine that generates additional electric energy; and three so-called classical heating systems based on: gas boiler, coal boiler, and a heat pump. Calculation includes covering the demand for electricity, which is purchased from the grid or produced in residential system. The presented analyses are partially based on an experimental investigation. The measurements of the heat pump system as well as those of the energy (electricity and heat) demand profiles in the analyzed building were conducted for a single-family house. The measurements of the µCHP unit were made using a laboratory stand prepared for simulating a variable heat demand. The overall efficiency of the µCHP was in the range of 88.6– 92.4%. The amounts of the produced/consumed energy (electricity, heat, and chemical energy of fuel) were determined. The consumption and the generation of electricity were settled on a daily basis. Operational costs of the heat pump system or coal boiler based heating system are lower comparing to the micro-cogeneration, however no support system for natural gas-based µCHP system is included.
    Źródło:
    Archives of Thermodynamics; 2019, 40, 1; 71-83
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    PCA-based approximation of a class of distributed parameter systems: classical vs. neural network approach
    Autorzy:
    Bartecki, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/201641.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    distributed parameter system
    principal component analysis
    artificial neural network
    supervised learning
    unsupervised learning
    Opis:
    In this article, an approximation of the spatiotemporal response of a distributed parameter system (DPS) with the use of the principal component analysis (PCA) is considered. Based on a data obtained by the numerical solution of a set of partial differential equations, a PCA-based approximation procedure is performed. It consists in the projection of the original data into the subspace spanned by the eigenvectors of the data covariance matrix, corresponding to its highest eigenvalues. The presented approach is carried out using both the classical PCA method as well as two different neural network structures: two-layer feed-forward network with supervised learning (FF-PCA) and single-layer network with unsupervised, generalized Hebbian learning rule (GHA-PCA). In each case considered, the effect of the approximation model structure represented by the number of eigenvectors (or, in the neural case, units in the network projection layer) on the mean square approximation error of the spatiotemporal response and on the data compression ratio is analysed. As shown in the paper, the best approximation quality is obtained for the classical PCA method as well as for the FF-PCA neural approach. On the other hand, an adaptive learning method for the GHA-PCA network allows to use it in e.g. an on-line identification scheme.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 3; 651-660
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Metrological Analysis of Precision of the System of Delivering a Water Capsule for Explosive Production of Water Aerosol
    Autorzy:
    Śmigielski, G.
    Toczek, W.
    Dygdała, R.
    Stefański, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/221553.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    water capsule airdrop control system
    uncertainty analysis
    GUM uncertainty framework
    propagation of distributions
    Opis:
    In this paper precision of the system controlling delivery by a helicopter of a water capsule designed for extinguishing large scale fires is analysed. The analysis was performed using a numerical method of distribution propagation (the Monte Carlo method) supplemented with results of application of the uncertainty propagation method. In addition, the optimum conditions for the airdrop are determined to ensure achieving the maximum area covered by the water capsule with simultaneous preserving the precision level necessary for efficient fire extinguishing.
    Źródło:
    Metrology and Measurement Systems; 2016, 23, 1; 47-58
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis of beam hypergraphs by means of exact and approximate methods as models of transverse vibrating subsystems in the synthesis of mechanical and mechatronic systems
    Hipergrafy belek analizowanych metodą dokładną i przybliżoną jako modele podukładów drgających giętnie w syntezie układów mechanicznych i mechatronicznych
    Autorzy:
    Buchacz, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/140054.pdf
    Data publikacji:
    2010
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    analiza hipergrafów belek
    metoda dokładna
    metoda przybliżona
    metoda Galerkina
    modelowanie
    graf
    system mechaniczny
    system mechatroniczny
    system drgający
    analysis of beam hypergraphs
    exact method
    approximated method
    Galerkin's method
    modelling
    graph
    mechanical system
    mechatronical system
    vibrating system
    Opis:
    In this paper, the author compares of the characteristics of subsystems obtained by the approximate and exact method in order to answer to the question - if the approximate method can be used to nominate the characteristics of mechatronic systems. Frequency - modal analysis has been presented for a mechanical system, i.e. transverse-vibrating clamped-free beam. Consequently, the model of the beam was presented in a five-vertex hypergraph. This model, in the case of approximate frequency-modal analysis, can be imitated in a three-vertex hypergraph. Such formulation could be the introduction to synthesis of transverse-vibrating complex beam systems with constant cross-section.
    W pracy porównano charakterystyki podukładów otrzymanych metodą przybliżoną i dokładną, aby odpowiedzieć na pytanie: czy metoda przybliżona może być stosowana do wyznaczania charakterystyk układów mechatronicznych. Analizę widmowo-modalną przeprowadzano w przypadku drgającej giętnie belki wysięgnikowej. Następnie model belki odwzorowano w pięciowierzchołkowy hipergraf, który to model, w wyniku zastosowania przybliżonej metody analizy widmowo - modalnej, można przedstawić w postaci hipergrafu trójwierzchołkowego. Takie ujęcie może stanowić wprowadzenie do syntezy drgających giętnie złożonych układów belkowych o odcinkowo stałym przekroju.
    Źródło:
    Archive of Mechanical Engineering; 2010, LVII, 4; 431-442
    0004-0738
    Pojawia się w:
    Archive of Mechanical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Research on stability and sensitivity of the rotating machines with overhung rotors to lateral vibrations
    Autorzy:
    Szolc, Tomasz
    Konowrocki, Robert
    Powiązania:
    https://bibliotekanauki.pl/articles/2090690.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    overhung rotor-shaft
    lateral vibrations
    stability analysis
    sensitivity analysis
    system imperfection
    wał wirnika
    drgania boczne
    analiza stabilności
    analiza wrażliwości
    niedoskonałość systemu
    Opis:
    The rotating machines with overhung rotors form a broad class of devices used in many types of industry. For this kind of rotor machine in the paper, there is investigated an inf luence of dynamic and static unbalance of a rotor, parallel and angular misalignments of shafts, and inner anisotropy of rigid couplings on system dynamic responses. The considerations are performed through a hybrid structural model of the machine rotor-shaft system, consisting of continuous beam finite elements and discrete oscillators. Numerical calculations are carried out for parameters characterizing a heavy blower applied in the mining industry. The main goal of the research is to assess the sensitivity of the imperfections mentioned above on excitation severity of rotor-shaft lateral vibrations and motion stability of the machine in question.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 6; e137987, 1--13
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fuzzy arithmetical analysis of multibody systems with uncertainties
    Analiza systemów wieloczłonowych z niepewnościami wykorzystująca arytmetykę rozmytą
    Autorzy:
    Walz, N. P.
    Hanss, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/950684.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    fuzzy arithmetic
    uncertainty
    multibody system
    robustness analysis
    arytmetyka rozmyta
    niepewność
    układ wieloczłonowy
    analiza odporności
    Opis:
    The consideration of uncertainties in numerical simulation is generally reasonable and is often indicated in order to provide reliable results, and thus is gaining attraction in various fields of simulation technology. However, in multibody system analysis uncertainties have only been accounted for quite sporadically compared to other areas. The term uncertainties is frequently associated with those of random nature, i.e. aleatory uncertainties, which are successfully handled by the use of probability theory. Actually, a considerable proportion of uncertainties incorporated into dynamical systems, in general, or multibody systems, in particular, is attributed to so-called epistemic uncertainties, which include, amongst others, uncertainties due to a lack of knowledge, due to subjectivity in numerical implementation, and due to simplification or idealization. Hence, for the modeling of epistemic uncertainties in multibody systems an appropriate theory is required, which still remains a challenging topic. Against this background, a methodology will be presented which allows for the inclusion of epistemic uncertainties in modeling and analysis of multibody systems. This approach is based on fuzzy arithmetic, a special field of fuzzy set theory, where the uncertain values of the model parameters are represented by so-called fuzzy numbers, reflecting in a rather intuitive and plausible way the blurred range of possible parameter values. As a result of this advanced modeling technique, more comprehensive system models can be derived which outperform the conventional, crisp-parameterized models by providing simulation results that reflect both the system dynamics and the effect of the uncertainties. The methodology is illustrated by an exemplary application of multibody dynamics which reveals that advanced modeling and simulation techniques using some well-thought-out inclusion of the presumably limiting uncertainties can provide significant additional benefit.
    Uwzględnienie niepewności w symulacji numerycznej jest generalnie rzeczą rozsadną. Podejście to często prowadzi do wiarygodnych rezultatów, toteż zyskuje na atrakcyjności w wielu dziedzinach technik symulacyjnych. Niemniej, w analizie systemów wieloczłonowych – inaczej niż w innych dziedzinach – niepewności były dotąd brane pod uwagę jedynie sporadycznie. Termin ”niepewność” jest często kojarzony z czynnikami o charakterze przypadkowym, tzn. niepewnościami aleatorycznymi, z którymi można z powodzeniem radzić sobie metodami teorii prawdopodobieństwa. W rzeczywistości, znaczna część niepewności występujących w systemach dynamicznych, a w szczególności w systemach wieloczłonowych, jest powiązana z tzw. niepewnościami epistemologicznymi, które obejmują m.in. niepewności spowodowane brakiem wiedzy, subiektywnością w implementacji modelu numerycznego, a także niepewności wynikajace z uproszczeń i idealizacji. Tak więc, by modelować niepewności epistemologiczne w systemach wieloczłonowych wymagana jest odpowiednia teoria, która wciąż stanowi poważne wyzwanie. Na tym tle, autorzy przedstawiają metodologię, która pozwala na włączenie niepewności epistemologicznych w proces modelowania i analizy systemów wieloczłonowych. Prezentowane podejście jest oparte na arytmetyce rozmytej, specjalnej dziedzinie teorii zbiorów rozmytych, gdzie niepewne wartości parametrów modelu są reprezentowane przez tzw. liczby rozmyte, które odzwierciedlają, w sposób raczej intuicyjny lecz przekonywujący, nieostry zakres możliwych wartości parametrów. W rezultacie użycia tej zaawansowanej techniki modelowania uzyskuje się bardziej wszechstronny model systemu, który daje lepsze wyniki niż modele tradycyjne, o sztywnej parametryzacji. Wyniki symulacji, uzyskane przy zastosowaniu takiego modelu, odzwierciedlają zarówno dynamikę systemu, jak i efekty związane z niepewnościami. Prezentowana metodologia jest zilustrowana przykładowym zastosowaniem do dynamiki systemu wieloczłonowego. Przykład pokazuje, że użycie zaawansowanych technik modelowania i symulacji, w których w sposób dobrze przemyślany uwzględniono prawdopodobne niepewności graniczne, może dostarczyć znacznych korzyści dodatkowych.
    Źródło:
    Archive of Mechanical Engineering; 2013, LX, 1; 109-125
    0004-0738
    Pojawia się w:
    Archive of Mechanical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    PSO based optimal location and sizing of SVC for novel multiobjective voltage stability analysis during N – 2 line contingency
    Autorzy:
    Mangaiyarkarasi, S. P
    Sree Renga Raja, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/140430.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    N – 2 contingency analysis
    voltage severity
    particle swarm optimization (PSO)
    SVC
    power system planning
    Opis:
    In this paper voltage stability is analysed based not only on the voltage deviations from the nominal values but also on the number of limit violating buses and severity of voltage limit violations. The expression of the actual state of the system as a numerical index like severity, aids the system operator in taking better security related decisions at control centres both during a period of contingency and also at a highly stressed operating condition. In contrary to conventional N – 1 contingency analysis, Northern Electric Reliability Council (NERC) recommends N – 2 line contingency analysis. The decision of the system operator to overcome the present contingency state of the system must blend harmoniously with the stability of the system. Hence the work presents a novel N – 2 contingency analysis based on the continuous severity function of the system. The study is performed on 4005 possible combinations of N – 2 contingency states for the practical Indian Utility 62 bus system. Static VAr Compensator is used to improve voltage profile during line contingencies. A multi- objective optimization with the objective of minimizing the voltage deviation and also the number of limit violating bus with optimal location and optimal sizing of SVC is achieved by Particle Swarm Optimization algorithm.
    Źródło:
    Archives of Electrical Engineering; 2014, 63, 4; 535-550
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Design and analysis of cementless hip-joint system using functionally graded material
    Autorzy:
    Asiri, Saeed
    Powiązania:
    https://bibliotekanauki.pl/articles/2065758.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    functionally graded material
    cementless hip-joint system
    natural frequency
    harmonic response
    fatigue analysis
    finite element analysis
    modal analysis
    odpowiedź harmoniczna
    analiza zmęczeniowa
    analiza elementów skończonych
    analiza modalna
    Opis:
    Functionally Graded Materials (FGM) are extensively employed for hip plant component material due to their certain properties in a specific design to achieve the requirements of the hip-joint system. Nevertheless, if there are similar properties, it doesn’t necessarily indicate that the knee plant is efficiently and effectively working. Therefore, it is important to develop an ideal design of functionally graded material femoral components that can be used for a long period. A new ideal design of femoral prosthesis can be introduced using functionally graded fiber polymer (FGFP) which will reduce the stress shielding and the corresponding stresses present over the interface. Herein, modal analysis of the complete hip plant part is carried out, which is the main factor and to date, very few research studies have been found on it. Moreover, this enhances the life of hip replacement, and the modal, harmonic, and fatigue analysis determines the pre-loading failure phenomena due to the vibrational response of the hip. This study deals with the cementless hip plant applying the finite element analysis (FEA) model in which geometry is studied, and the femoral bone model is based in a 3D scan.
    Źródło:
    Archive of Mechanical Engineering; 2022, LXIX, 1; 129--146
    0004-0738
    Pojawia się w:
    Archive of Mechanical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Low Power and High Performance Hardware Design for Automatic Epilepsy Seizure Detection
    Autorzy:
    Rafiammal, S. Syed
    Najumnissa, D.
    Anuradha, G.
    Mohideen, S. Kaja
    Jawahar, P. K.
    Mutalib, Syed Abdul
    Powiązania:
    https://bibliotekanauki.pl/articles/963923.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    epilepsy detection
    system on chip
    implementation
    Quadrature Linear Discriminant Analysis
    hardware design
    seizure detection
    Opis:
    An application specific integrated design using Quadrature Linear Discriminant Analysis is proposed for automatic detection of normal and epilepsy seizure signals from EEG recordings in epilepsy patients. Five statistical parameters are extracted to form the feature vector for training of the classifier. The statistical parameters are Standardised Moment, Co-efficient of Variance, Range, Root Mean Square Value and Energy. The Intellectual Property Core performs the process of filtering, segmentation, extraction of statistical features and classification of epilepsy seizure and normal signals. The design is implemented in Zynq 7000 Zc706 SoC with average accuracy of 99%, Specificity of 100%, F1 score of 0.99, Sensitivity of 98% and Precision of 100 % with error rate of 0.0013/hr., which is approximately zero false detection.
    Źródło:
    International Journal of Electronics and Telecommunications; 2019, 65, 4; 707-712
    2300-1933
    Pojawia się w:
    International Journal of Electronics and Telecommunications
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Sizing of prosumer hybrid renewable energy systems in Poland
    Autorzy:
    Bartecka, M.
    Terlikowski, P.
    Kłos, M.
    Michalski, Ł.
    Powiązania:
    https://bibliotekanauki.pl/articles/200243.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    hybrid renewable energy system
    prosumer
    energy efficiency
    techno-economic analysis
    optimal power source sizing
    Opis:
    Nowadays the demand for renewable energy sources is constantly growing. There are several reasons of such state, including requirements for energy-efficient new buildings and reduction of greenhouse gas emissions. An exemplary solution that may help to reduce “traditional” primary energy consumption is local energy source utilization. The article presents a simplified feasibility study of hybrid energy system under Polish law and economic conditions for a self-government unit, that is legally obliged to apply means of energy efficiency improvement. The aim of this paper is to provide a simple algorithm to find optimal hybrid PV and wind power source sizing for a prosumer. Resource data used in analyses are imported from Photovoltaic Geographical Information System and cover a period of one year. The paper includes two different methodologies applied to solve the problem of optimal hybrid energy system sizing. The first approach is heuristic and based on monthly energy balancing while the second is iterative and takes into account hourly energy balance. The results from both methods are compared and verified by HomerPro software, that shows significant differences between two algorithms. At the end economic assessment based on Net Present Value method is performed.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2020, 68, 4; 721-731
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Sensitivity analysis for power plant pumping systems in breakdown
    Autorzy:
    Karaśkiewicz, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/140098.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Suter characteristics
    pumping system
    centrifugal pump
    power plant breakdown
    transient analysis
    charakterystyka Sutera
    system pompujący
    pompa wirowa
    awaria elektrowni
    analiza przejściowa
    Opis:
    The small number of available complete modern pump characteristics makes the safety analysis of nuclear and conventional power plants based on the characteristics made over half a century ago of specific speeds nq = 24.6,147.1 and 261.4. The aim of the paper is to check sensitivity of the power plant system response for different complete pump characteristics–modern and available from older tests for nq = 24.6, 147.1 and 261.4. It has been shown that Suter’s characteristics for modern pumps give a different response to the pumping system of a power plant in break down than those used so far.
    Źródło:
    Archive of Mechanical Engineering; 2018, LXV, 3; 349-359
    0004-0738
    Pojawia się w:
    Archive of Mechanical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Application of novel discrete differential operator of periodic function to study electromechanical interactions
    Autorzy:
    Sobczyk, T. J.
    Radzik, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/201412.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    electromechanical system
    steady state analysis
    periodic solutions
    analysis in time domain
    discrete differential operator
    iterative algorithms
    system elektromechaniczny
    analiza stanu ustalonego
    rozwiązania okresowe
    analiza w dziedzinie czasu
    dyskretny operator różniczkowania
    algorytm iteracyjny
    Opis:
    This paper investigates an algorithm for finding steady-states in electromechanical systems for the cases of their periodic nature. The algorithm enables to specify the steady-state solution identified directly in time domain. The basis for such an algorithm is a discrete differential operator that specifies the values of the first derivative of the periodic function in the selected set of points on the basis of the values of that function in the same set of points. It creates algebraic equations describing the steady-state solution for the nonlinear differential equations describing electromechanical systems. In this paper, the direct time-domain approach is tested for the simple converter considering. The algorithm used in this paper is competitive with respect to the one known in literature an approach based on the harmonic balance method operated in frequency domain.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2018, 66, 5; 645-653
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Influence of Taguchi-Grey Relational Analysis of Gating System Design on Mechanical Properties of Casting
    Autorzy:
    Ingle, P. D.
    Narkhede, B. E.
    Powiązania:
    https://bibliotekanauki.pl/articles/383260.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    mechanical properties
    gating system design
    aluminum casting
    Taguchi technique
    Grey Relational Analysis
    GRA
    właściwości mechaniczne
    stopy aluminium
    techniki Taguchi
    Gray Relational Analysis
    Opis:
    Throughout the casting process, mold filling plays a very significant role in the casting quality control. It is important to study the effect of gating system design on ingate velocity of the metal which affects the mechanical properties of casting. The effect of varying the design of four gating system elements namely pouring cup, sprue height, runner and ingate design on the multiple responses like tensile strength and percentage elongation is studied using a Taguchi’s L9 OA. The Taguchi technique was coupled with a Grey Relational Analysis (GRA) to obtain a Grey Relational Grade (GRG) for evaluating multiple responses. ANOVA has been applied to identify the significance of different parameters and it was found that the pouring cup design and the runner cross-section along its length collectively contributed above 76% of the total GRG value. Finally, the confirmation tests were performed to validate the predicted optimized results and it established an improvement of 9.90% from the initial design.
    Źródło:
    Archives of Foundry Engineering; 2019, 3; 72-77
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Proposal for the assessment of steel truss reliability under fire conditions
    Propozycja oceny niezawodności stalowej kratownicy w warunkach pożarowych
    Autorzy:
    Kubicka, K.
    Radoń, U.
    Powiązania:
    https://bibliotekanauki.pl/articles/231070.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    warunki pożarowe
    kratownica stalowa
    niezawodność
    ocena niezawodności
    system szeregowy
    system równoległy
    analiza pożarowa
    wskaźnik niezawodności
    fire conditions
    steel truss
    reliability
    reliability assessment
    serial system
    parallel system
    fire analysis
    reliability index
    Opis:
    The paper presents a proposal for the assessment of the reliability of steel truss (both statically determinate and indeterminate) in the persistent and accidental design situation. In the analysis, a probabilistic approach was used. The global Hasofer-Lind reliability index was employed, computed in successive time steps for the whole structure, not for individual elements. The statically determinate truss was modelled as a serial system from the reliability standpoint. For the statically indeterminate truss, kinematically admissible failure mechanisms were determined by means of the examination of the singularity of the stiffness matrix of the structure, converting the truss into a geometrically variable system. For the problem thus formulated, a serial-parallel reliability model was constructed. Monitoring the reliability index in the successive minutes of the fire makes it possible to estimate the probability of the structure failure, and to decide whether the required safety level is maintained.
    Artykuł przedstawia propozycję oceny niezawodności stalowej kratownicy (statycznie wyznaczalnej i niewyznaczalnej) w podstawowej i wyjątkowej sytuacji projektowej. W analizie zastosowano podejście probabilistyczne z globalnym wskaźnikiem niezawodności Hasofera-Linda obliczanym w kolejnych krokach czasowych dla konstrukcji jako całości, a nie poszczególnych elementów. Kratownica statycznie wyznaczalna została zamodelowana jako układ szeregowy z punktu widzenia niezawodności. Dla kratownicy statycznie niewyznaczalnej poprzez badanie osobliwości macierzy sztywności konstrukcji określono kinematycznie dopuszczalne mechanizmy zniszczenia, przekształcające ją w układ geometrycznie zmienny. Dla tak postawionego zadania zbudowano szeregowo-równoległy model niezawodnościowy. Stal jest materiałem chętnie wykorzystywanym w budownictwie ze względu na szereg korzystnych właściwości, głównie mechanicznych. Niemniej jednak nie jest to materiał pozbawiony wad. Główną, najpoważniejszą jest wyjątkowo niska odporność na wysokie temperatury. Wraz ze wzrostem temperatury gazów pożarowych właściwości mechaniczne stali: granica plastyczności i moduł sprężystości ulegają redukcji co w bezpośredni sposób przekłada się na spadek nośności.
    Źródło:
    Archives of Civil Engineering; 2015, 61, 4; 141-154
    1230-2945
    Pojawia się w:
    Archives of Civil Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Dyskurs na temat legalnych substancji psychoaktywnych w perspektywie teorii systemowej Niklasa Luhmanna
    Discourse on Legal Psychoactive Substances from the Perspective of the Niklas Luhmann’s System Theory
    Autorzy:
    Skrzypulec, Błażej
    Powiązania:
    https://bibliotekanauki.pl/articles/427124.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    discourse analysis
    system theory
    Niklas Luhmann
    drug policy
    analiza dyskursu
    teoria systemowa
    Luhmann
    polityka narkotykowa
    Opis:
    The article analyzes a particular type of discourse produced by the political system: the discourse onthe legal psychoactive substances market in Poland. The Luhmann’s system theory forms the theoretical foundation for the research. The main concepts of the system theory are presented and the attempt is made to suggest how discourse analytical methods can be applied to studyingLuhmann’s systems. The research material comprises the drug policy related statements of politicians and officialsthat appeared in press and parliamentary stenographic records as well as relevant legal documents. The material comes from the period between August 2008 and August 2009 when an amendment to the drug act was drafted and passed. The conclusion stemming from the analysis is that the concept “drug” is most crucially determining the political system’s discourse on psychoactive substances. The interpretations and uses of the concept “drug” as well as the ways, in which these uses make the concept an efficient mechanism of the complexity reduction, are studied.
    W tekście prezentowane są wyniki analizy dyskursu generowanego przez system polity- ki, który dotyczy polskiego rynku sklepów sprzedających legalne substancje psychoaktywne – tzw. „dopalacze”. Teoretycznym zapleczem artykułu jest teoria systemowa Niklasa Luh- manna. Przedstawione są główne pojęcia teorii systemowej oraz wskazuje się, jak metody związane z analizą dyskursu mogą być użyte do badania luhmannowskich systemów. Anali- zie poddano wypowiedzi polityków i urzędników, z artykułów prasowych oraz stenogramów z posiedzeń Sejmu i Senatu, a także akty prawne związane z polityką narkotykową. Badane są materiały od sierpnia 2008 do sierpnia 2009 – przeprowadzono wówczas nowelizację usta- wy o przeciwdziałaniu narkomanii, mającą utrudnić działanie sklepom z „dopalaczami”. Na podstawie przeprowadzonej analizy sformułowana zostaje teza, że elementem, który najistot- niej determinuje dyskurs systemu polityki na temat substancji psychoaktywnych jest pojęcie „narkotyku”. W tekście wskazuje się, w jaki sposób jest ono rozumiane i używane oraz jak taki sposób użycia czyni zeń efektywny mechanizm redukcji złożoności.
    Źródło:
    Studia Socjologiczne; 2012, 1(204); 149-175
    0039-3371
    Pojawia się w:
    Studia Socjologiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Thermal analysis of heat and power plant with high temperature reactor and intermediate steam cycle
    Autorzy:
    Fic, A.
    Składzień, J.
    Gabriel, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/239939.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    cogeneration system
    high-temperature reactor
    exergy analysis
    gas heat pumps
    numerical simulation
    system kogeneracyjny
    reaktor wysokotemperaturowy
    analiza egzergii
    gazowe pompy ciepła
    symulacja numeryczna
    Opis:
    Thermal analysis of a heat and power plant with a high temperature gas cooled nuclear reactor is presented. The main aim of the considered system is to supply a technological process with the heat at suitably high temperature level. The considered unit is also used to produce electricity. The high temperature helium cooled nuclear reactor is the primary heat source in the system, which consists of: the reactor cooling cycle, the steam cycle and the gas heat pump cycle. Helium used as a carrier in the first cycle (classic Brayton cycle), which includes the reactor, delivers heat in a steam generator to produce superheated steam with required parameters of the intermediate cycle. The intermediate cycle is provided to transport energy from the reactor installation to the process installation requiring a high temperature heat. The distance between reactor and the process installation is assumed short and negligable, or alternatively equal to 1 km in the analysis. The system is also equipped with a high temperature argon heat pump to obtain the temperature level of a heat carrier required by a high temperature process. Thus, the steam of the intermediate cycle supplies a lower heat exchanger of the heat pump, a process heat exchanger at the medium temperature level and a classical steam turbine system (Rankine cycle). The main purpose of the research was to evaluate the effectiveness of the system considered and to assess whether such a three cycle cogeneration system is reasonable. Multivariant calculations have been carried out employing the developed mathematical model. The results have been presented in a form of the energy efficiency and exergy efficiency of the system as a function of the temperature drop in the high temperature process heat exchanger and the reactor pressure.
    Źródło:
    Archives of Thermodynamics; 2015, 36, 1; 3-18
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Noise Detection for Biosignals Using an Orthogonal Wavelet Packet Tree Denoising Algorithm
    Autorzy:
    Schimmack, M.
    Mercorelli, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/226940.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    noise detection
    wavelet packet transform
    wavelet analysis
    Daubechies wavelet
    linux-based embedded system
    ARM processor platform
    Opis:
    This article deals with the noise detection of discrete biosignals using an orthogonal wavelet packet. In specific, it compares the usefulness of Daubechies wavelets with different vanishing moments for the denoising and compression of the digitalised biosignals in case of surface electromyography (sEMG) signals. The work is based upon the discrete wavelet transform (DWT) version of wavelet package transform (WPT). A noise reducing algorithm is proposed to detect unavoidable noise in the acquired data in a model independent way. The noise of a signal sequence will be defined by a seminorm. This method was developed for a possible observation during a fracture healing period. The proposed method is general for signal processing and its design was based upon the wavelet packet.
    Źródło:
    International Journal of Electronics and Telecommunications; 2016, 62, 1; 15-21
    2300-1933
    Pojawia się w:
    International Journal of Electronics and Telecommunications
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The 8AE-PD computer measurement system for registration and analysis of acoustic emission signals generated by partial discharges in oil power transformers
    Autorzy:
    Witos, Franciszek
    Opilski, Zbigniew
    Szerszeń, Grzegorz
    Setkiewicz, Maciej
    Powiązania:
    https://bibliotekanauki.pl/articles/220623.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    acoustic emission
    partial discharge
    multichannel system
    acoustic signal detection
    acoustic signal processing
    signal analysis
    voltage preamplifier
    Opis:
    A computer measurement system, designed and built by authors, dedicated to location and description of partial discharges (PD) in oil power transformers examined by means of the acoustic emission (AE) method is presented. The measurement system is equipped with 8 measurement channels and ensures: monitoring of signals, registration of data in real time within a band of 25-1000 kHz in laboratory and real conditions, basic and advanced analysis of recorded signals. The basic analysis carried out in the time, frequency and time-frequency domains deals with general properties of the AE signals coming from PDs. The advanced analysis, performed in the discrimination threshold domain, results in identification of signals coming from different acoustic sources as well as location of these sources in the examined transformers in terms of defined by authors descriptors and maps of these descriptors on the side walls of the tested transformer tank. Examples of typical results of laboratory tests carried out with the use of the built-in measurement system are presented.
    Źródło:
    Metrology and Measurement Systems; 2019, 26, 2; 403-418
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Exergy analysis of the performance of low-temperature district heating system with geothermal heat pump
    Autorzy:
    Sekret, R.
    Nitkiewicz, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/240813.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    exergy analysis
    low-temperature geothermal water
    district heating system
    analiza egzergii
    niskotemperaturowa woda geotermalna
    ciepłownictwo systemowe
    Opis:
    Exergy analysis of low temperature geothermal heat plant with compressor and absorption heat pump was carried out. In these two concepts heat pumps are using geothermal water at 19.5°C with spontaneous outflow 24 m3/h as a heat source. The research compares exergy efficiency and exergy destruction of considered systems and its components as well. For the purpose of analysis, the heating system was divided into five components: geothermal heat exchanger, heat pump, heat distribution, heat exchanger and electricity production and transportation. For considered systems the primary exergy consumption from renewable and non-renewable sources was estimated. The analysis was carried out for heat network temperature at 50/40°C, and the quality regulation was assumed. The results of exergy analysis of the system with electrical and absorption heat pump show that exergy destruction during the whole heating season is lower for the system with electrical heat pump. The exergy efficiencies of total system are 12.8% and 11.2% for the system with electrical heat pump and absorption heat pump, respectively.
    Źródło:
    Archives of Thermodynamics; 2014, 35, 1; 77-86
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Determination of Input Parameters of the Neural Network Model, Intended for Phoneme Recognition of a Voice Signal in the Systems of Distance Learning
    Autorzy:
    Akhmetov, B.
    Tereykovsky, I.
    Doszhanova, A.
    Tereykovskaya, L.
    Powiązania:
    https://bibliotekanauki.pl/articles/226378.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    neural networks
    phonemes
    recognition of a voice signal
    system of distance learning
    mel-cepstral coefficients
    spectral analysis
    Opis:
    The article is devoted to the problem of voice signals recognition means introduction in the system of distance learning. The results of the conducted research determine the prospects of neural network means of phoneme recognition. It is also shown that the main difficulties of creation of the neural network model, intended for recognition of phonemes in the system of distance learning, are connected with the uncertain duration of a phoneme-like element. Due to this reason for recognition of phonemes, it is impossible to use the most effective type of neural network model on the basis of a multilayered perceptron, at which the number of input parameters is a fixed value. To mitigate this shortcoming, the procedure, allowing to transform the non-stationary digitized voice signal to the fixed quantity of mel-cepstral coefficients, which are the basis for calculation of input parameters of the neural network model, is developed. In contrast to the known ones, the possibility of linear scaling of phoneme-like elements is available in the procedure. The number of computer experiments confirmed expediency of the fact that the use of the offered coding procedure of input parameters provides the acceptable accuracy of neural network recognition of phonemes under near-natural conditions of the distance learning system. Moreover, the prospects of further research in the field of development of neural network means of phoneme recognition of a voice signal in the system of distance learning is connected with an increase in admissible noise level. Besides, the adaptation of the offered procedure to various natural languages, as well as to other applied tasks, for instance, a problem of biometric authentication in the banking sector, is also of great interest.
    Źródło:
    International Journal of Electronics and Telecommunications; 2018, 64, 4; 425-432
    2300-1933
    Pojawia się w:
    International Journal of Electronics and Telecommunications
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Air curtain as a barrier for smoke in case of fire: Numerical modelling
    Autorzy:
    Krajewski, G.
    Węgrzyński, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/201389.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    fire
    air curtain
    tunnel ventilation
    smoke exhaust system
    heat exhaust system
    CFD analysis
    ogień
    kurtyny powietrzne
    wentylacja w tunelu
    dym
    układ wydechowy ciepła
    analizy CFD
    Opis:
    This paper presents the basic information about the use of air curtains in fire safety, as a barrier for heat and smoke. The mathematical model of an air curtain presented allows to estimate the velocity of air in various points of space, including the velocity of air from an angled air curtain. Presented equations show how various parameters influence the performance of an air curtain, thus allowing for better understanding of its principle of operation. Further, authors present results of their previous studies on air curtain performance and validation studies on various turbulence models used in CFD analysis. Results of new studies are presented with regards to the performance of an air curtain in case of fire, and final remarks on its design are given.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2015, 63, 1; 145-153
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A hierarchical preference voting system for mining method selection problem
    Wykorzystanie systemu głosowania zakładający hierarchię preferencji przy wyborze odpowiedniej metody wybierania
    Autorzy:
    Nourali, H.
    Nourali, S.
    Ataei, M.
    Imanipour, N.
    Powiązania:
    https://bibliotekanauki.pl/articles/219350.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    wybór metody wybierania
    procesy decyzyjne
    preferencyjny system głosowania
    metoda obwiedni danych
    mining method selection
    Multi Attribute Decision Making (MADM)
    preference voting system
    data envelopment analysis
    Opis:
    To apply decision making theory for Mining Method Selection (MMS) problem, researchers have faced two difficulties in recent years: (i) calculation of relative weight for each criterion, (ii) uncertainty in judgment for decision makers. In order to avoid these difficulties, we apply a Hierarchical Preference Voting System (HPVS) for MMS problem that uses a Data Envelopment Analysis (DEA) model to produce weights associated with each ranking place. The presented method solves the problem in two stages. In the first stage, weights of criteria are calculated and at the second stage, alternatives are ranked with respect to all criteria. A simple case study has also been presented to illustrate the competence of this method. The results show that this approach reduces some difficulties of previous methods and could be applied simply in group decision making with too many decision makers and criteria. Also, regarding to application of a mathematical model, subjectivity is reduced and outcomes are more reliable.
    Przy wykorzystywaniu teorii decyzyjnych do zagadnień związanych z wyborem właściwej metody wybierania, badacze na przestrzeni lat napotykali na dwie zasadnicze trudności: (i) obliczenie odpowiedniego współczynnika wagi dla poszczególnych kryteriów oraz (ii) niepewność osądów dokonywanych przez decydentów. W celu uniknięcia tych trudności, zastosowaliśmy system głosowania zakładający hierarchię preferencji przy podejmowaniu decyzji odnośnie wyboru metody wybierania. W tym celu wykorzystano model DEA (metoda obwiedni danych) dla wygenerowania wag związanych z poszczególnymi pozycjami w rankingu. Proponowana metoda zakłada rozwiązanie problemu w dwóch etapach. W pierwszym etapie obliczane są wagi przyporządkowane poszczególnym kryteriom, w etapie drugim przeprowadzany jest ranking rozwiązań alternatywnych w odniesieniu do wszystkich kryteriów. Przedstawiono proste studium przypadku dla zilustrowania działania metody. Wyniki wskazują, że zastosowane podejście redukuje pewne niedogodności związane z poprzednio stosowanymi metodami i może być z powodzeniem wykorzystane do podejmowania decyzji grupowych, w sytuacjach gdy mamy do czynienia z wieloma decydentami i wieloma kryteriami. Ponadto, zastosowanie modelu matematycznego pozwala na ograniczenie subiektywizmu w ocenie, dzięki temu wyniki są bardziej wiarygodne.
    Źródło:
    Archives of Mining Sciences; 2012, 57, 4; 1056-1070
    0860-7001
    Pojawia się w:
    Archives of Mining Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The xCELLigence system for real-time and label-free analysis of neuronal and dermal cell response to Equine Herpesvirus type 1 infection
    Autorzy:
    Golke, A.
    Cymerys, J.
    Slonska, A.
    Dzieciatkowski, T.
    Chmielewska, A.
    Tucholska, A.
    Banbura, M.W.
    Powiązania:
    https://bibliotekanauki.pl/articles/30665.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    xCELLigence system
    real-time analysis
    label-free analysis
    neuronal cell response
    dermal cell response
    cell response
    equine herpesvirus 1
    animal infection
    herpesvirus
    neuron
    neuronal cell
    dermal cell
    Opis:
    Real-time cell electronic sensing (RT-CES) based on impedance measurements is an emerging technology for analyzing the status of cells in vitro. It allows label-free, real time monitoring of the biological status of cells. The present study was designed to assess dynamic data on the cell processes during equine herpesvirus type 1 (EHV-1) infection of ED (equine dermal) cells and primary murine neuronal cell culture. We have demonstrated that the xCELLigence system with dynamic monitoring can be used as a rapid diagnostic tool both to analyze cellular behavior and to investigate the effect of viral infection.
    Źródło:
    Polish Journal of Veterinary Sciences; 2012, 15, 1
    1505-1773
    Pojawia się w:
    Polish Journal of Veterinary Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Costs analysis of iron casts manufacturing
    Autorzy:
    Kukla, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/382760.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    technologia informatyczna
    przemysł odlewniczy
    system transportowy
    analiza kosztów
    ergonomia pracy
    stanowisko pracy
    information technology
    foundry industry
    transport system
    costs analysis
    work ergonomics
    workstations
    production systems rationalisation
    Opis:
    The article presents the issues of costs analysis of iron casts manufacturing using automated foundry lines. Particular attention was paid to departmental costs, conversion costs and costs of in-plant transport. After the Pareto analysis had been carried out, it was possible to set the model area of the process and focus on improving activities related to finishing of a chosen group of casts. In order to eliminate losses, the activities realised in this domain were divided into activities with added value, activities with partially added value and activities without added value. To streamline the production flow, it was proposed to change the location of workstations related to grinding, control and machining of casts. Within the process of constant improvement of manufacturing processes, the aspect of work ergonomics at a workstation was taken into account. As a result of the undertaken actions, some activities without added value were eliminated, efficiency was increased and prime costs of manufacturing casts with regard to finishing treatment were lowered.
    Źródło:
    Archives of Foundry Engineering; 2012, 12, 2; 45-48
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Predicting the relationship between system vibration with rock brittleness indexes in rock sawing process
    Prognozowanie związku pomiędzy drganiami urządzenia a współczynnikiem kruchości skał w trakcie ich urabiania
    Autorzy:
    Mikaeil, R.
    Ataei, M.
    Ghadernejad, S.
    Sadegheslam, G.
    Powiązania:
    https://bibliotekanauki.pl/articles/219619.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    drgania urządzenia
    współczynnik kruchości skał
    proces urabiania skał
    analiza statystyczna
    system vibration
    brittleness indexes
    sawing process
    statistical analysis
    Opis:
    The system vibration is a very significant measure of the sawing performance, because it indicates the amount of energy required to saw the rock. The maintenance cost of system is also dependant on system vibration. A few increases in system vibration cause a huge increase in the maintenance cost of the system. In this paper, the vibration of system in terms of RMSa was investigated and models for estimation of vibration by means of rock brittleness indexes and operational specifications were designed via statistical models and multiple curvilinear regression analysis. In this study, the relationships between rock brittleness indexes and operational specifications were investigated by regression analysis in statistical package for social science (SPSS) and the results of determination coefficients have been presented. In the second part, the diagrams show that a point lying on the line indicates an exact estimation. In the plot for model, the points are scattered uniformly about the diagonal line, suggesting that the models are good. It is very useful to evaluate the vibration of system and select the suitable operational characteristics by only some mechanical properties of rock.
    Drgania układu uważane są za miernik wydajności procesu urabiania, ponieważ pokazują ilość energii niezbędnej do urabiania skały. Od poziomu drgań zależą także koszty eksploatacji systemu. Nieznaczny nawet wzrost poziomu drgań prowadzi do znacznego zwiększenia kosztów eksploatacyjnych urządzenia. W pracy tej przeprowadzono analizę drgań (ich wartości skutecznych) i opracowano model estymacji poziomu drgań w oparciu o współczynnik kruchości skał i parametry eksploatacyjne urządzenia. W pracy wykorzystano modele statystyczne i wielokrotną analizę metodą regresji krzywoliniowej. W pracy obecnej związek pomiędzy współczynnikiem kruchości skał a parametrami eksploatacyjnymi urządzenia badano z wykorzystaniem analizy metodą regresji dostępnej w statystycznym pakiecie oprogramowania dla nauk społecznych (SPSS) a wyniki podano w postaci wyznaczonych współczynników. W drugiej części pracy przedstawiono wykres pokazujący, ze punkt leżący na linii oznacza dokładne oszacowanie. W wykresie wykonanym dla modelu punkty rozrzucone są równomiernie wokół linii przekątnej, co sugeruje że modele są właściwe. Określenie poziomu drgań urządzenia jest niezwykle korzystnym zabiegiem pozwalającym na dobór parametrów pracy urządzenia jedynie w oparciu o mechaniczne właściwości skał.
    Źródło:
    Archives of Mining Sciences; 2014, 59, 1; 139-153
    0860-7001
    Pojawia się w:
    Archives of Mining Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    DSC Analysis of Order–Disorder Transition in Ni3Al Based Alloys From Ni-Al-Cr System
    Analiza DSC przemian typu porządek-nieporządek w stopach na osnowie Ni3Al z układu Ni-Al-Cr
    Autorzy:
    Maciąg, T.
    Rzyman, K.
    Przeliorz, R.
    Powiązania:
    https://bibliotekanauki.pl/articles/356471.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Ni-Al-Cr system
    intermetallic phase Ni3Al
    order-disorder
    DSC analysis
    system Ni-Al-Cr
    faza międzymetaliczna Ni3Al
    faza nieuporządkowana
    analiza DSC
    Opis:
    Ni-Al-Cr system is significant for industrial alloys based on intermetallic phase Ni3Al, that crystallizes in crystal lattice L12. It is indicated as γ′, contrary to disordered phase γ which occurs with addition of chromium. DSC analysis was performed on alloys of chemical composition from Ni75Al25÷Ni75Cr25 range of Ni-rich part of Ni-Al-Cr system. In addition, few measurements were conducted using DTA method. Based on curves registered, it was possible to identify characteristic temperature during heating and cooling of the sample. It corresponds to existence of phase boundary γ′+γ / γ in examined alloys. Results of thermal analysis were compared with results obtained with other method performed by authors which is solution calorimetric method.
    Układ Ni-Al-Cr jest ważnym układem dla przemysłowych stopów na osnowie fazy międzymetalicznej Ni3Al, która krystalizuje w uporządkowanej sieci L12. Oznacza się ją jako γ′ w odróżnieniu od fazy nieuporządkowanej γ, która pojawia się wraz z dodatkiem stopowym chromu. Wykonano serię stopów, których skład chemiczny leży na linii Ni75Al25÷Ni75Cr25 w bogatej w nikiel części układu Ni-Al-Cr i poddano je analizie DSC. Dodatkowo wykonano kilka pomiarów metodą DTA. Na podstawie zarejestrowanych krzywych udało się zidentyfikować charakterystyczne temperatury podczas nagrzewania i studzenia próbki. Odpowiadają one miejscom występowania granicy międzyfazowej γ′+γ / γ w stopach. Wyniki analiz termicznych zestawiono z wynikami innej metody zastosowanej przez autorów tj. kalorymetrycznej metody typu rozpuszczania.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 3A; 1871-1876
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Optimal sizing and cost analysis of hybrid power system for a stand-alone application in Coimbatore region: a case study
    Autorzy:
    Bogaraj, T.
    Kanakaraj, J.
    Kumar, K. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/141602.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    hybrid power system
    optimal sizing
    cost analysis
    renewable energy sources
    net present cost
    levelised cost of energy
    HOMER
    Opis:
    This paper presents the optimal sizing of PV/Wind/Fuel Cell/Battery Hybrid Energy System for energizing a Small Scale Industrial Application or a village domestic load of 200 kW. HOMER software is used for simulation of the complete system. The solar radiation data and wind speed data used in this paper are for the place of Coimbatore, Tamil Nadu, India which is located 11.0183° N longitude and 76.9725° E latitude. The optimized sizes of components of Hybrid Power System (HPS) are found based on Levelised Cost of Energy (LCE) and total Net Present Cost (NPC). The results are presented and compared for five different combinations of HPS components. Suggestions are also presented to choose the low cost system which produces energy at low LCE.
    Źródło:
    Archives of Electrical Engineering; 2015, 64, 1; 139-155
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Numeryczna analiza przepływów w wybranych fragmentach układów wlewowych stosowanych przy wytwarzaniu odlewów wielkogabarytowych
    Numerical Analysis of Flows in Selected Parts of the Gating Systems Used in Large-size Castings Production
    Autorzy:
    Goraj, T.
    Szucki, M.
    Lelito, J.
    Suchy, J. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/380475.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    analiza numeryczna
    układy wlewowe
    odlewy wielkogabarytowe
    pęcherze gazowe
    FLOW-3D
    numerical analysis
    large-size castings
    filling system
    Opis:
    Niniejsza praca zawiera analizę przepływów dwufazowych (ciekły metal - gaz) w wybranym fragmencie układów wlewowych, stosowanych przy produkcji wielkogabarytowych odlewów ze stopów żelaza, w oparciu o symulacje komputerowe wykonane w programie FLOW-3D. W ramach publikacji dobrano układy modelowe oraz parametry symulacji numerycznych. Na podstawie uzyskanych wyników badań szczegółowo przestudiowano rozkład prędkości i ciśnienia w tych układach oraz wskazano obszary narażone na erozję materiału ceramicznego i miejsca kumulowania się gazów.
    Current work includes an analysis of the two-phase flows (liquid metal - gas) in a selected parts of the gating systems, used in large-size iron castings production. The studies were carried out with the use of FLOW-3D software. Within the paper a model system and the parameters of numerical simulations were selected. Based on the obtained results, the velocity and pressure profile in the model systems were analyzed as well as the areas susceptible to erosion of the ceramic material and gas entrainment were indicated.
    Źródło:
    Archives of Foundry Engineering; 2014, 14, 4 spec.; 25-30
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Vibration control and performance analysis of full car active suspension system using fractional order terminal sliding mode controller
    Autorzy:
    Yuvapriya, T.
    Lakshami, P.
    Rajendiran, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/230099.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    active suspension system
    fractional order terminal sliding mode controller
    ISO8608
    ISO2631
    stability analysis
    vibration dose value
    Opis:
    The main goal of introducing Active Suspension System in vehicles is to reduce the vehicle body motion under road obstacles which improves the ride comfort of the passenger. In this paper, the Full Car Model (FCM) with seven Degrees of Freedom is considered and simulated by MATLAB/Simulink. The Terminal Sliding Mode Controller (TSMC) and Fractional Order Terminal Sliding Mode Controller (FOTSMC) are designed to enhance the ride quality, stability and passenger comfort for FCM. The designed FOTSMC has the ability to provide higher control accuracy in a finite time. The performances of the designed controllers are evaluated by measuring the vehicle body vibration in both angular and vertical direction under bump input and ISO-8608 random input against passive suspension system. The Frequency Weighted Root Mean Square (FWRMS) and Vibration dose value of Body Acceleration as per ISO-2631 are evaluated for FOTSMC, TSMC and PSS. The stability of the FCM is proved by Lyapunouv theory. Further analysis with sprung mass and speed variation of FCM demonstrate the robustness of proposed controller. To investigate the performances of designed controllers, comparison is made with existing Sliding Mode Controller (SMC) which proves that the designed FOTSMC performs better than existing SMC.
    Źródło:
    Archives of Control Sciences; 2020, 30, 2; 295-324
    1230-2384
    Pojawia się w:
    Archives of Control Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Causes and effects of adverse events during water supply and sewerage system constructions
    Przyczyny oraz skutki zdarzeń niepożądanych na budowach systemów wodociągowych i kanalizacyjnych
    Autorzy:
    Rybka, I.
    Bondar-Nowakowska, E.
    Połoński, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/231154.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    system wodociągowy
    system kanalizacyjny
    roboty budowlane
    przerwa w pracy
    analiza przyczyn
    zdarzenie niepożądane
    wada dokumentacji
    termin realizacji
    koszt inwestycji
    water supply system
    sewerage system
    construction works
    work stoppage
    causes analysis
    adverse event
    documentation defect
    completion date
    investment cost
    Opis:
    This paper identifies the adverse events occurring during the execution of water supply and sewerage systems construction. The basis for this paper is research conducted in 2010-2014 on the construction sites of water supply and sewerage systems located in the provinces of Lower Silesia and Opole. The research consisted of direct observations of construction sites and review of construction documentation. It showed that work stoppages on the examined construction sites were frequent. They were caused by violations of work discipline by the production employees, adverse weather conditions, and defects in the project documentation. The study demonstrated that in almost every case, these bad an adverse effect on the completion date and budget of the investment. The analyses show that in such important and expensive investments as water supply and sewerage systems, organizational structures in which a special role is assigned to middle-rank personnel should be adopted.
    W latach 2010-2014 na dwunastu budowach wodociągowych i kanalizacyjnych, realizowanych na terenie województw dolnośląskiego i opolskiego, przeprowadzono badania które miały na celu identyfikację zdarzeń niepożądanych. W przypadku większości rozpatrywanych inwestycji zarówno termin zakończenia inwestycji jak i budżet określony w kontrakcie były przekroczone. Przeprowadzone badania stanowiły podstawę do oceny wpływu zidentyfikowanych zdarzeń na czas trwania i koszt inwestycji. Badania polegały na bezpośredniej obserwacji stanowisk roboczych oraz obejmowały przegląd dokumentacji budowy. Obserwacje terenowe wykonano metodą migawkową w okresie jednego roku. W czasie ich prowadzenia, na rozpatrywanych budowach, wykonywane były głównie wykopy oraz montaż rurociągów.
    Źródło:
    Archives of Civil Engineering; 2016, 62, 1; 173-184
    1230-2945
    Pojawia się w:
    Archives of Civil Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparative analyses of residential building efficiency for AC and DC distribution networks
    Autorzy:
    Ahmad, Faraz
    Dastgeer, Faizan
    Gelani, Hasan E.
    Khan, Sidra
    Nasir, Mashood
    Powiązania:
    https://bibliotekanauki.pl/articles/2173601.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    DC distribution system
    efficiency analysis
    AC vs DC
    residential buildings
    solar PV
    system dystrybucji prądu stałego
    analiza wydajności
    prąd zmienny
    prąd stały
    AC/DC
    budynki mieszkalne
    fotowoltaika
    Opis:
    The escalating prevalence of rooftop solar PVs and DC powered home appliances are the driving forces for the research in the field of DC distribution at residential level. The current research work presents comparative analyses of AC and DC distribution systems considering various scenarios for the specific purpose of efficiency/energy savings. A modern Bakersfield CA, USA home is considered for the analyses. The loads are classified according to the power demand. Rooftop solar PVs are also included in each residential building. Mathematical equations are devised for the efficiency analysis of residential buildings powered with AC as well as DC. The results reveal strong dependence of the efficiency values on the utilization/types of loads, efficiencies of the power electronic converters (PECs), solar capacity and seasonal conditions, as a function of the time of day. It is concluded that AC system presents better efficiency values as compared to the DC counterpart except during the time periods when solar power is available and when the penetration of variable speed drive (VSD) based loads is high.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 2; art. no. e136732
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparative analyses of residential building efficiency for AC and DC distribution networks
    Autorzy:
    Ahmad, Faraz
    Dastgeer, Faizan
    Gelani, Hasan E.
    Khan, Sidra
    Nasir, Mashood
    Powiązania:
    https://bibliotekanauki.pl/articles/2128137.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    DC distribution system
    efficiency analysis
    AC vs DC
    residential buildings
    solar PV
    system dystrybucji prądu stałego
    analiza wydajności
    prąd zmienny
    prąd stały
    AC/DC
    budynki mieszkalne
    fotowoltaika
    Opis:
    The escalating prevalence of rooftop solar PVs and DC powered home appliances are the driving forces for the research in the field of DC distribution at residential level. The current research work presents comparative analyses of AC and DC distribution systems considering various scenarios for the specific purpose of efficiency/energy savings. A modern Bakersfield CA, USA home is considered for the analyses. The loads are classified according to the power demand. Rooftop solar PVs are also included in each residential building. Mathematical equations are devised for the efficiency analysis of residential buildings powered with AC as well as DC. The results reveal strong dependence of the efficiency values on the utilization/types of loads, efficiencies of the power electronic converters (PECs), solar capacity and seasonal conditions, as a function of the time of day. It is concluded that AC system presents better efficiency values as compared to the DC counterpart except during the time periods when solar power is available and when the penetration of variable speed drive (VSD) based loads is high.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 2; e136732, 1--9
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Process of market strategy optimization using distributed computing systems
    Autorzy:
    Nowicki, W.
    Bera, A.
    Błaszyński, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/407280.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    economic systems
    financial system
    moving average models
    optimization problems
    performance analysis
    prediction methods
    prediction problems
    project management
    work organization
    Opis:
    If market repeatability is assumed, it is possible with some real probability to deduct short term market changes by making some calculations. The algorithm, based on logical and statistically reasonable scheme to make decisions about opening or closing position on a market, is called an automated strategy. Due to market volatility, all parameters are changing from time to time, so there is need to constantly optimize them. This article describes a team organization process when researching market strategies. Individual team members are merged into small groups, according to their responsibilities. The team members perform data processing tasks through a cascade organization, providing solutions to speed up work related to the use of remote computing resources. They also work out how to store results in a suitable way, according to the type of task, and facilitate the publication of a large amount of results.
    Źródło:
    Management and Production Engineering Review; 2015, 6, 4; 87-93
    2080-8208
    2082-1344
    Pojawia się w:
    Management and Production Engineering Review
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Quantitative safety analysis of train control system based on statistical model checking
    Autorzy:
    Lin, Junting
    Min, Xiaoqin
    Powiązania:
    https://bibliotekanauki.pl/articles/2124711.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    train control systems
    statistical model checking
    safety analysis
    hybrid automata
    UPPAAL-SMC
    system sterowania pociągiem
    analiza bezpieczeństwa
    automaty hybrydowe
    Opis:
    With the rapid development of communication technology, the Train-centric Communication-based Train Control (TcCBTC) system adopting the train-train communication mode to reduce the transmission link of control information, will become the direction of urban rail transit field development. At present, TcCBTC system is in the stage of key technology research and prototype development. Uncertain behavior in the process of system operation may lead to operation accidents. Therefore, before the system is put into use, it must undergo strict testing and security verification to ensure the safe and efficient operation of the system. In the paper, the formal modeling and quantitative analysis of train tracking operation under moving block are carried out. Firstly, the structure of TcCBTC system and the train tracking interval control strategy under moving block conditions are analyzed. The subsystem involved in train tracking and the uncertain factors in system operation are determined. Then, based on the Stochastic Hybrid Automata (SHA), a network of SHA model of train dynamics model, communication components and on-board controller in the process of train tracking is established, which can formally describe the uncertain environment in the process of system operation. UPPAAL-SMC is used to simulate the change curve of train position and speed during tracking, it is verified that the model meets the safety requirements in static environment. Finally, taking Statistical Model Checking (SMC) as the basis of safety analysis, the probability of train collision in uncertain environment is calculated. The results show that after accurately modeling the train tracking operation control mechanism through network of SHA, the SMC method can accurately calculate the probability of train rearend collision, which proves that the method has strong feasibility and effectiveness. Formal modeling and analysis of safety-critical system is very important, which enables designers to grasp the hidden dangers of the system in the design stage and safety evaluation stage of train control system, and further provides theoretical reference for the subsequent TcCBTC system design and development, practical application and related specification improvement.
    Źródło:
    Archives of Transport; 2022, 61, 1; 7--19
    0866-9546
    2300-8830
    Pojawia się w:
    Archives of Transport
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Deterministic models and stochastic simulations in multiple reaction models in systems biology
    Autorzy:
    Laroch, P.
    Puszynski, K.
    Polanski, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/80910.pdf
    Data publikacji:
    2011
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    deterministic model
    stochastic simulation
    multiple reaction model
    stochastic approach
    modelling
    biomolecular reaction
    system biology
    computational analysis
    algorithm
    living organism
    biomolecule
    Źródło:
    BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2011, 92, 3
    0860-7796
    Pojawia się w:
    BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Rotating combustion chambers as a key feature of effective timing of turbine engine working according to Humphrey cycle – CFD analysis
    Autorzy:
    Tarnawski, Piotr
    Ostapski, Wiesław
    Powiązania:
    https://bibliotekanauki.pl/articles/2173712.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    pressure gain combustion
    Humphrey cycle
    turbine engine
    CFD analysis
    valve timing system
    isochoric combustion
    engine energy efficiency
    sealing system
    ciśnienie spalania
    cykl Humphreya
    silnik turbinowy
    analiza CFD
    układ rozrządu
    spalanie izochoryczne
    sprawność energetyczna silnika
    system uszczelniający
    Opis:
    The paper presents a concept of a new turbine engine with the use of rotating isochoric combustion chambers. In contrast to previously analyzed authors’ engine concepts, here rotating combustion chambers were used as a valve timing system. As a result, several practical challenges could be overcome. An effective ceramic sealing system could be applied to the rotating combustion chambers. It can assure full tightness regardless of thermal conditions and related deformations. The segment sealing elements working with ceramic counter-surface can work as self-alignment because of the centrifugal force acting on them. The isochoric combustion process, gas expansion, and moment generation were analyzed using the CFD tool (computational fluid dynamics). The investigated engine concept is characterized by big energy efficiency and simple construction. Finally, further improvements in engine performance are discussed.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2022, 70, 5; art. no. e143100
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Morphology and developmental potential of bovine parthenotes after spontaneous activation in vitro
    Autorzy:
    Lechniak, D
    Cieslak, D.
    Sosnowski, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/2048294.pdf
    Data publikacji:
    1998
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    blastomere
    bovine oocyte
    cytogenetic analysis
    parthenogenetic activation
    morphology
    in vitro
    fertilization system
    blastocyst
    oocyte
    insemination
    morphological evaluation
    maturation
    embryo production
    Opis:
    Spontaneous parthenogenetic activation of bovine oocytes in an in vitro maturation and fertilization system (IVM/IVF) is described. Altogether, 1403 follicular oocytes, collected by the aspiration method, were matured in vitro and then cultured without insemination in the same conditions as a group of inseminated oocytes. After 48-72 h of additional culture, 141 oocytes (10%) were found to be spontaneously activated. Morphological evaluation revealed that the number of blastomeres within parthenotes ranged from 2 to 16 cells, with a minority (15.7%) comprising of 9-16 blastomeres. According to a cytogenetic analysis, only 1.2% of the analysed parthenotes consisted of more than 9 cells. Parthenotes may not be distinguished from embryos produced in vitro and spontaneous parthenogenetic activation in an IVM/IVF system indicates suboptimal culture conditions. A group of non-inseminated oocytes should be included in each experiment to serve as a control. Spontaneously activated bovine parthenotes only occasionaly developed beyond the 8-blastomere stage in a common IVM/IVF system. The incidence of parthenotes interferes with the efficiency of in vitro embryo production but it is doubtful whether it lowers the pregnancy rate after transfer of IVF embryos.
    Źródło:
    Journal of Applied Genetics; 1998, 39, 2; 193-198
    1234-1983
    Pojawia się w:
    Journal of Applied Genetics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Simulation and Casting Process of Aluminum Alloy Multi-Way Valve Body with Various Gating Systems
    Autorzy:
    Rong, L.
    Lunjun, C.
    Ming, S.
    Qi, Z.
    Yong, L.
    Heng, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/381887.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    casting process
    aluminum alloy
    valve body
    gating system
    simulation analysis
    proces odlewniczy
    stop aluminium
    korpus zaworu
    układ wlewowy
    analiza symulacji
    Opis:
    In order to study the effects of various gating systems on the casting of a complex aluminum alloyed multi-way valve body, both software simulation analysis and optimization were carried out. Following, the aluminum alloyed multi-way valve body was cast to check the pouring of the aluminum alloy valve body. The computer simulation results demonstrated that compared to the single side casting mode, the casting method of both sides of the gating system would reduce the filling of the external gas, while the air contact time would be lower. Adversely, due to the pouring on both sides, the melt cannot reach at the same time, leading to the liquid metal speed into the cavity to differ, which affected the liquid metal filling stability. The riser unreasonable setting led to the solidification time extension, resulting in a high amount of casting defects during solidification. Also, both gating systems led the entire casting inconsequential solidification. To overcome the latter problems, a straight gate was set at the middle pouring and the horizontal gate diversion occurred on both sides of pouring, which could provide better casting results for the aluminum alloyed multi-valve body.
    Źródło:
    Archives of Foundry Engineering; 2018, 18, 2; 84-94
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Active Transient Sound Radiation Control from a Smart Piezocomposite Hollow Cylinder
    Autorzy:
    Hasheminejad, S. M.
    Rabbani, V.
    Powiązania:
    https://bibliotekanauki.pl/articles/177572.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    active structural acoustic control (ASAC) thick cylindrical shells
    exact elasto-acoustic analysis
    time-domain solution
    intelligent system
    sound field attenuation
    Opis:
    The linear 3D piezoelasticity theory along with active damping control (ADC) strategy are applied for non-stationary vibroacoustic response suppression of a doubly fluid-loaded functionally graded piezolaminated (FGPM) composite hollow cylinder of infinite length under general time-varying excitations. The control gain parameters are identified and tuned using Genetic Algorithm (GA) with a multi-objective performance index that constrains the key elasto-acoustic system parameters and control voltage. The uncontrolled and controlled time response histories due to a pair of equal and opposite impulsive external point loads are calculated by means of Durbin’s numerical inverse Laplace transform algorithm. Numerical simulations demonstrate the superior (good) performance of the GA-optimized distributed active damping control system in effective attenuation of sound pressure transients radiated into the internal (external) acoustic space for two basic control configurations. Also, some interesting features of the transient fluid-structure interaction control problem are illustrated via proper 2D time domain images and animations of the 3D sound field. Limiting cases are considered and accuracy of the formulation is established with the aid of a commercial finite element package as well as comparisons with the current literature.
    Źródło:
    Archives of Acoustics; 2015, 40, 3; 359-381
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Impact of waste heat recovery systems on energy efficiency improvement of a heavy-duty diesel engine
    Autorzy:
    Ma, Z.
    Chen, H.
    Zhang, Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/240819.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    energy efficiency design index
    energy efficiency operational indicator
    waste heat recovery system
    performance analysis
    reduction factor
    wskaźnik efektywności energetycznej
    wskaźniki eksploatacyjny efektywności energetycznej
    system odzysku ciepła odpadowego
    analiza wydajności
    współczynnik redukcyjny
    Opis:
    The increase of ship’s energy utilization efficiency and the reduction of greenhouse gas emissions have been high lightened in recent years and have become an increasingly important subject for ship designers and owners. The International Maritime Organization (IMO) is seeking measures to reduce the CO2 emissions from ships, and their proposed energy efficiency design index (EEDI) and energy efficiency operational indicator (EEOI) aim at ensuring that future vessels will be more efficient. Waste heat recovery can be employed not only to improve energy utilization efficiency but also to reduce greenhouse gas emissions. In this paper, a typical conceptual large container ship employing a low speed marine diesel engine as the main propulsion machinery is introduced and three possible types of waste heat recovery systems are designed. To calculate the EEDI and EEOI of the given large container ship, two software packages are developed. From the viewpoint of operation and maintenance, lowering the ship speed and improving container load rate can greatly reduce EEOI and further reduce total fuel consumption. Although the large container ship itself can reach the IMO requirements of EEDI at the first stage with a reduction factor 10% under the reference line value, the proposed waste heat recovery systems can improve the ship EEDI reduction factor to 20% under the reference line value.
    Źródło:
    Archives of Thermodynamics; 2017, 38, 3; 63-75
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis and Validation of Database in Computer Aided Design of Jewellery Casting
    Autorzy:
    Ignaszak, Z.
    Wojciechowski, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/382474.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    casting of jewelry
    Au-Ag-Cu alloy
    computer design
    thermal analysis
    solidification
    CAE system
    NF&S
    quality
    odlewanie biżuterii
    stop Au-Ag-Cu
    projektowanie komputerowe
    analiza termiczna
    krzepnięcie
    system CAE
    jakość
    Opis:
    An overview of the bibliography regarding the connection of knowledge about precious metal alloys and aspects of the use of computer aided technologies to the optimization of the jewelry casting processes is presented. An analysis of the usability of selected CAx systems was made: 1) for spatial design, called Rhinoceros 6 and 2) CAE system: NovaFlow & Solid (NF&S). The authors describe own research including data acquisition and evaluation of temperature variations during solidification of the selected Au-Ag-Cu alloy, with the identification of the phase transformations of this alloy. The intensity of heat exchange was changed (cooling of specimens under ambient temperature conditions – "normal" intensity and with the furnace – very slow cooling). The problem of completing the simulation database was pointed out and analyzed. Examples of simulations of casting selected jewelry (ring and signet) were given and compared with the result of the experiment realized in real conditions. It was confirmed that the optimization by combining experimental and simulation studies allows for the acquisition of new knowledge, and also facilitates the creation of new artistic designs of jewelry as well as performing the feasibility check, and then optimizing the chosen technology.
    Źródło:
    Archives of Foundry Engineering; 2020, 20, 1; 9-16
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Zbrodnicza przemoc sadomasochizmu? Zewnętrzne ramy interpretacji działań społecznych stosowane przez wymiar sprawiedliwości
    SINISTER VIOLENCE OF SADOMASOCHISM? OUTER FRAMES OF INTERPRETATION OF SOCIAL ACTION USED IN NORMALISING INSTITUTIONS
    Autorzy:
    Marzec, Wiktor
    Powiązania:
    https://bibliotekanauki.pl/articles/427513.pdf
    Data publikacji:
    2011
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    BDSM
    FRAME ANALYSIS
    INTERPRETATIVE PROCEDURES
    JURIDICAL SYSTEM
    SADOMASOCHISM
    SEXUAL PRACTICES
    VIOLENCE
    sado/masochizm
    przemoc
    analiza ramowa
    mniejszości seksualne
    procedury interpretatywne
    instytucje prawne
    Opis:
    Konsensualny sado/masochizm pozostaje pośród najbardziej potępianych praktyk seksualnych podejmowanych dobrowolnie przez osoby dorosłe. Główna kontrowersja dotyczy interpretacji podejmowanej przemocy. Nauki społeczne podjęły alternatywną i krytyczną wobec tradycji klinicznej refleksję nad sadyzmem i masochizmem. Zachodzące w przestrzeni społecznej procesy ujmowania w ramy i przekształcenia interpretacyjne mogą być opisane z pomocą analizy ramowej Ervinga Goffmana. W szerszym planie ta krańcowa i wyrazista sytuacja ukazuję rolę, jaką w pracy instytucji normalizacyjnych, prawnych, medycznych może odgrywać zewnętrzna interpretacja zdarzeń dokonywana przez ich przedstawicieli, odmienna od interpretacji podejmujących te praktyki społeczne. Fakt ten musi jednak pozostać nieuświadomionym, by instytucje te mogły operatywnie działać.
    Sadomasochism still is one of the most intensively criminalized sexual practices undertaken by consenting adults. The main controversy regards the interpretation of the violence acts involved. Social sciences have undertaken an alternative reflection on sadism and masochism, critical towards the clinical tradition. The interpretation processes, and framing of activities may be described using Erving Goffman's frame analysis. In the broader perspective this extreme and striking situation demonstrates the role played in the normalizing social control institutions such as justice administration or medical bodies by the external interpretative procedures carried out by their representatives, as differing from the interpretations of the persons conducting this sort of social practices. However, this influence needs to stay unconscious in order for these institutions to operate in an efficient manner.
    Źródło:
    Studia Socjologiczne; 2011, 4(203); 177-192
    0039-3371
    Pojawia się w:
    Studia Socjologiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    System approach to the analysis of an integrated oxy-fuel combustion power plant
    Autorzy:
    Ziębik, A.
    Gładysz, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/240507.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    system approach
    input-output analysis
    oxy-fuel combustion
    cumulative energy
    exergy consumption
    system exergy losses
    thermoecological cost
    zarządzanie jakością
    analiza wejścia-wyjścia
    spalanie w tlenie
    energia skumulowana
    zużycie egzergii
    straty egzergii
    koszt termoekologiczny
    Opis:
    Oxy-fuel combustion (OFC) belongs to one of the three commonly known clean coal technologies for power generation sector and other industry sectors responsible for CO2 emissions (e.g., steel or cement production). The OFC capture technology is based on using high-purity oxygen in the combustion process instead of atmospheric air. Therefore flue gases have a high concentration of CO2 - Due to the limited adiabatic temperature of combustion some part of CO2 must be recycled to the boiler in order to maintain a proper flame temperature. An integrated oxy-fuel combustion power plant constitutes a system consisting of the following technological modules: boiler, steam cycle, air separation unit, cooling water and water treatment system, flue gas quality control system and CO2 processing unit. Due to the interconnections between technological modules, energy, exergy and ecological analyses require a system approach. The paper present the system approach based on the 'input-output' method to the analysis of the: direct energy and material consumption, cumulative energy and exergy consumption, system (local and cumulative) exergy losses, and thermoecological cost. Other measures like cumulative degree of perfection or index of sustainable development are also proposed. The paper presents a complex example of the system analysis (from direct energy consumption to thermoecological cost) of an advanced integrated OFC power plant.
    Źródło:
    Archives of Thermodynamics; 2014, 35, 3; 39-57
    1231-0956
    2083-6023
    Pojawia się w:
    Archives of Thermodynamics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Shock safety modeling method for low-voltage electric devices
    Autorzy:
    Korniluk, W.
    Sajewicz, D.
    Powiązania:
    https://bibliotekanauki.pl/articles/141402.pdf
    Data publikacji:
    2010
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    zarządzanie bezpieczeństwem
    system ekspertowy
    sieć bayesowska
    prawdopodobieństwo całkowite
    bezpieczeństwo porażeniowe
    safety management process
    expert system
    Bayesian network
    total probability
    protection reliability states
    appearance of touch and electric shock states
    risk analysis and assessment
    Opis:
    The article describes a shock safety modeling method for low-voltage electric devices, based on using a Bayesian network. This method allows for taking into account all possible combinations of the reliability and unreliability states for the shock protection elements under concern. The developed method allows for investigating electric shock incidents, analysing and assessing shock risks, as well as for determining criteria of dimensioning shock protection means, also with respect to reliability of the particular shock protection elements. Dependencies for determining and analysing the probability of appearance of reliability states of protection as well as an electric shock risk are presented in the article.
    Źródło:
    Archives of Electrical Engineering; 2010, 59, 3-4; 153-167
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Data mining system for air quality monitoring networks
    Autorzy:
    Czechowski, P.
    Badyda, A.
    Majewski, G.
    Powiązania:
    https://bibliotekanauki.pl/articles/204820.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    air pollutants
    data quality analysis
    data mining
    estimation
    exploratory methods
    harmonic
    principal component analysis
    statistical tests outliers
    influential
    leverage observations
    analytical software system
    programming
    Eco Data Miner
    EDM
    Winsorized mean
    Cook
    Mahalanobis distance
    DFITS
    COVRATIO
    Opis:
    The use of quantitative methods, including stochastic and exploratory techniques in environmental studies does not seem to be sufficient in practical aspects. There is no comprehensive analytical system dedicated to this issue, as well as research regarding this subject. The aim of this study is to present the Eco Data Miner system, its idea, construction and implementation possibility to the existing environmental information systems. The methodological emphasis was placed on the one-dimensional data quality assessment issue in terms of using the proposed QAAH1 method - using harmonic model and robust estimators beside the classical tests of outlier values with their iterative expansions. The results received demonstrate both the complementarity of proposed classical methods solution as well as the fact that they allow for extending the range of applications significantly. The practical usefulness is also highly significant due to the high effectiveness and numerical efficiency as well as simplicity of using this new tool.
    Źródło:
    Archives of Environmental Protection; 2013, 39, 4; 123-147
    2083-4772
    2083-4810
    Pojawia się w:
    Archives of Environmental Protection
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Subsynchronous oscillation and its mitigation of VSC-MTDC with doubly-fed induction generator-based wind farm integration
    Autorzy:
    Su, Miaohong
    Dong, Maiying
    Liu, Kaiqi
    Zou, Weiwei
    Powiązania:
    https://bibliotekanauki.pl/articles/1841370.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    doubly-fed induction generator
    eigenvalue analysis
    multi-channel variable-parameter subsynchronous damping controller
    subsynchronous oscillation voltage source converter
    multi-terminal direct current transmission system
    Opis:
    Wind power integration through the voltage source converter-based high-voltage direct current (VSC-HVDC) system will be a potential solution for delivering large-scalewind power to the “Three-North Regions” of China. However, the interaction between the doubly-fed induction generator (DFIG) and VSC-HVDC system may cause the risk of subsynchronous oscillation (SSO). This paper establishes a small-signal model of the VSC based multi-terminal direct current (VSC-MTDC) system with new energy access for the problem, and the influencing factors causing SSO are analyzed based on the eigen valueanalysis method. The theoretical analysis results show that the SSO in the system is related to the wind farm operating conditions, the rotor-side controller (RSC) of the DFIG and the interaction of the controller in the VSC-MTDC system. Then, the phase lag characteristicis obtained based on the signal test method, and a multi-channel variable-parameter subsynchronous damping controller (SSDC) is designed via selecting reasonable parameters.Finally, the correctness of the theoretical analysis and the effectiveness of the multi-channelvariable-parameter SSDC are verified based on time-domain simulation.
    Źródło:
    Archives of Electrical Engineering; 2021, 70, 1; 53-72
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Determination of parameters for a design of the stable electro-dynamic passive magnetic support of a high-speed flexible rotor
    Autorzy:
    Szolc, T.
    Falkowski, F.
    Henzel, M.
    Kurnyta-Mazurek, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/201250.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    rotor dynamics
    electrodynamic passive magnetic bearings
    active magnetic damper
    stability analysis
    rotor- shaft system
    dynamika rotora
    wirnik
    amortyzator magnetyczny
    analiza stabilności
    pasywne łożysko magnetyczne
    Opis:
    Electro-dynamic passive magnetic bearings are now viewed as a feasible option when looking for support for high-speed rotors. Nevertheless, because of the skew-symmetrical visco-elastic properties of such bearings, they are prone to operational instability. In order to avoid this, the paper proposes the addition of external damping into the newly designed vibrating laboratory rotor-shaft system. This may be achieved by means of using simple passive dampers that would be found among the components of the electro-dynamic bearing housings along with magnetic dampers, which satisfy the operational principles of active magnetic bearings. Theoretical investigations are going to be conducted by means of a structural computer model of the rotor-shaft under construction, which will take into consideration its actual dimensions and material properties. The additional damping magnitudes required to stabilize the most sensitive lateral eigenmodes of the object under consideration have been determined by means of the Routh-Hurwitz stability criterion.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2019, 67, 1; 91-105
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Shock safety modelling of indirect contact with low-voltage electric devices
    Autorzy:
    Korniluk, W.
    Sajewicz, D.
    Powiązania:
    https://bibliotekanauki.pl/articles/141066.pdf
    Data publikacji:
    2011
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    zarządzanie bezpieczeństwem
    system ekspertowy
    sieć bayesowska
    prawdopodobieństwo całkowite
    ochrona przeciwporażeniowa
    porażenie prądem elektrycznym
    safety management process
    expert system
    Bayesian network
    total probability
    protection reliability states
    appearance of touch and electric shock states
    risk analysis and assessment
    Opis:
    The article presents a shock safety model of an indirect contact with a low-voltage electric device. This model was used for computations and analyses concerning the following: the probabilities of appearance of the particular shock protection unreliability states, electric shock states (ventricular fibrillation), contributions of the unreliability of different shock protection elements to the probability of occurrence of these states, as well as the risk of electric shock (and the shock safety), and contributions of the intensity of occurrence of damages to different shock protection elements to this risk. An example of a possibility to reduce the risk of an electric shock through changing the intensity of occurrence of damages to the selected protection elements was provided.
    Źródło:
    Archives of Electrical Engineering; 2011, 60, 3; 303-315
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Modern hybrid joints in arospace: modelling and testing
    Nowoczesne połączenia hybrydowe w Lotnictwie: modelowanie i badania eskperymentalne
    Autorzy:
    Sadowski, T.
    Balawender, T.
    Śliwa, R.
    Golewski, P.
    Kneć, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/350876.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    zaciskanie
    połączenia hybrydowe
    połączenie nit-klej
    połączenie klincz-klej
    połączenie zgrzewanie punktowe-klejenie
    analiza elementów skończonych
    system cyfrowej korelacji obrazu
    clinching
    hybrid joint
    rivet-adhesive bonded joint
    clinch - adhesive joint
    spot welding - adhesive joint
    FEA (finite element analysis)
    DIC (digital image correlation system)
    Opis:
    The aim of the paper is to review different types of modern hybrid joints applied in aerospace. We focused on three particular cases: 1) spot welding - adhesive, 2) rivet-bonded and 3) clinch-bonded joints. The numerical models presented in the paper for these joints describe their complex behaviour under mechanical loading. The numerical calculations performed using ABAQUS code were compared to experimental results obtained by application of the Digital Image Correlation system (DIC) ARAMIS. The results investigated within the paper lead to the following major conclusions: - the strengthening of joints by application of adhesive significantly improve static strength, - the final failure of the joined structural system significantly depends on the surface adhesive area, - the stiffening effects of the hybrid joint lead to higher reliability and durability of the structural joints.
    W pracy dokonano przeglądu różnych typów połączeń hybrydowych stosowanych w lotnictwie. Szczególną uwagę zwrócono na trzy typy połączeń: 1) zgrzewanie punktowe - klejenie, 2) nitowanie - klejenie, 3) klinczowanie - klejenie. Modele numeryczne złączy zawarte w pracy, ujawniają złożoną i trudną do przewidzenia reakcję tych złączy na obciążenia mechaniczne. Obliczenia numeryczne porównano z wynikami eksperymentalnymi otrzymanymi za pomocą bezdotykowego systemu pomiaru odkształcen i naprężeń (DIC) ARAMIS. Główne wnioski z prezentowanych badań: - zastosowanie kleju powoduje istotne zwiększenie wytrzymałości statycznej testowanych połączeń, - na końcowy efekt zniszczenia złącza hybrydowego znaczący wpływ ma powierzchnia złącza klejowego, - zwiększona sztywność złączy hybrydowych powoduje, że mają one większą niezawodność i trwałość jako połączenia konstrukcyjne.
    Źródło:
    Archives of Metallurgy and Materials; 2013, 58, 1; 163-169
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Results of the promethee method application in selecting the technological system at the Majdan III open pit mine
    Wyniki zastosowania metody promethee do wyboru systemu technologicznego w kopalni odkrywkowej Majdan III
    Autorzy:
    Vujic, S.
    Hudej, M.
    Miljanovic, I.
    Powiązania:
    https://bibliotekanauki.pl/articles/218810.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    analiza obejmująca wiele zmiennych
    metoda promethee
    wspomaganie procesów decyzyjnych
    wybór ciągu technologicznego
    kopalnia odkrywkowa Majdan III
    multi-variate analysis
    decision-making support
    technological system selection
    Majdan III open pit mine
    Opis:
    This paper discusses the application of the PROMETHEE model and the results achieved in practice, following the example of the multi-criteria selection of the technological system at the Majdan III clay mineral raw material open pit mine of the Potisje Company, Republic of Serbia. After the introduction comments, reasons are explained for selecting the new technological system, conditions and limitations for the seven alternative solutions considered are described, mathematical foundation for the PROMETHEE method and a multi-criteria model of the problem in question are presented. The solution with the following structure was ranked first and accepted by the Company management as the best: Bucket chain excavator - Conveyor belts - Spreader (ECS), alongside a decision is made on the acquisition of machinery and system construction. The system was put into operation in 2000. The experience and the data accumulated in the previous twelve years confirm that the decision made on the application of the ECS technology was just, and the conclusion lists the benefits achieved.
    W artykule omówiono zastosowanie modelu Promethee i przedyskutowano uzyskane w ten sposób wyniki na przykładzie wielokryterialnego wyboru systemu technologicznego do zastosowania w kopalni odkrywkowej minerałów ilastych Majdan III, należącej do przedsiębiorstwa górniczego Potisje (Republika Serbii). Po uwagach wprowadzających przedstawiono powody wyboru nowego ciągu technologicznego, omówiono warunki oraz ograniczenia dla siedmiu alternatywnych rozwiązań, podstawy matematyczne metody Promethee oraz wielokryterialny model zagadnienia. Rozwiązanie uznane za najlepsze i zaaprobowane przez zarząd przedsiębiorstwa zakłada zastosowanie następującego ciągu technologicznego: koparka łancuchowa jednonaczyniowa - przenośniki taśmowe - rozkładarka(system ECS). Podjęto także decyzje odnośnie zakupu sprzętu i instalacji systemu, który uruchomiony został w 2000 roku. Doświadczenia i danezebrane z przeciągu ostatnich dwunastu lat potwierdzają zasadność wyboru systemu technologicznego. W podsumowaniu zestawiono listę uzyskanych korzyści.
    Źródło:
    Archives of Mining Sciences; 2013, 58, 4; 1229-1240
    0860-7001
    Pojawia się w:
    Archives of Mining Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-88 z 88

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