Temat: lifetime - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Implementation of mathematical model of thermal behavior of electronic components for lifetime estimation based on multi-level simulation
Autorzy:: Frivaldsky, M.
Pridala, M.
Drgona, P.
Powiązania:: https://bibliotekanauki.pl/articles/140808.pdf
Data publikacji:: 2017
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: electrolytic capacitor
lifetime model
lifetime estimation
system-level simulation
Opis:: The main purpose of the paper is the proposal of multi-level simulation, suited for the evaluation of the lifetime of critical electronic devices (electrolytic capacitors). The aim of this issue is to imagine about the expected operation of complex and expensive power electronic systems, when the failure of the most critical component occurs. For that reason, various operational conditions and various physical influences must be considered (e.g. mechanical, humidity, electrical, heat stress), where nonlinearities are naturally introduced. Verification of the proposal is given, whereby the life-time estimation of an electrolytic capacitor operated in a DC-DC converter during various operational conditions is shown. At this point electrical and heat stress is considered for lifetime influence. First, the current state in the field of mathematical modeling of the lifetime for electrolytic capacitors, considering main phenomena is introduced. Next, individual sub-models for multi-level simulation purposes are developed, including a thermal simulation model and electrical simulation model. Several complexities of individual models are mutually compared in order to evaluate their accuracy and suitability for further use. Proper simulation tools have been mutually linked and data transfer was secured, in order to have the possibility of investigation of a lifetime depend on the changes of various variables.
Źródło:: Archives of Electrical Engineering; 2017, 66, 2; 339-350
1427-4221
2300-2506
Pojawia się w:: Archives of Electrical Engineering
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Numerical investigation of creep behaviour of high-temperature steam turbine compone
Autorzy:: Banaszkiewicz, M.
Powiązania:: https://bibliotekanauki.pl/articles/175375.pdf
Data publikacji:: 2012
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: creep
lifetime assessment
steam turbine
Opis:: The paper presents a model for creep basing on the so-called characteristic creep strain. It illustrates its application in computations of old steam turbines components. The presented model is a modification of the Norton model which relates the stress exponent to the creep rupture strength and current stress. Creep strain is a function of the above two quantities, i.e., rupture strength and current stress, and acharacteristic creep strain which is material constant for a given time and temperature. Computational examples regard the rotating and pressure components analysed using the finite element method.
Źródło:: Transactions of the Institute of Fluid-Flow Machinery; 2012, 124; 5-15
0079-3205
Pojawia się w:: Transactions of the Institute of Fluid-Flow Machinery
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Methodology of threat autonomous assessment and forecasting the lifetime of the marine structure
Autorzy:: Murawski, L.
Powiązania:: https://bibliotekanauki.pl/articles/245864.pdf
Data publikacji:: 2015
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: monitoring systems
non-destructive tests
ship structures lifetime prediction
damage identification
damage localization
lifetime forecasting
Opis:: Structural Health Monitoring (SHM) is a natural extension and supplement of Non-Distractive Tests (NDT). Structure assessment during periodical NDT tests is performed by highly trained human team. However, during long sea voyage, ship crew has no knowledge and possibility for detailed assessment and, what is more, has no knowledge lifetime predicting of ship structure. SHM systems should have good designed sensors types, distribution, and automatic recording unit. However, most important (and most difficult for designing) is autonomous and self-contained procedures for marine structures hazard assessment. In the paper, basic assumptions for numerical algorithms of signal processing, damage identification and localization, threat assessment and forecasting of structure lifetime are presented. SHM systems can be based on several different measurements techniques like: comparative vacuum monitoring, electromagnetic layer, Lamb waves, vibration based methods, acoustic emission, and fibre optics. Last three methods are most promising in the marine environment, according to the author experience. Global ship hull deformation should be monitored as quasi-continuous measurements. Optical Time-Domain Reflectometer method (OTDR) is planned by author for hull global deformation monitoring. Some local strain-stress concentration of hull structure and propulsion system bearings' reactions will be monitored by Fibre Bragg Grating (FBG) sensors. Both techniques (OTDR and FBG) have been shortly described in the paper.
Źródło:: Journal of KONES; 2015, 22, 2; 163-168
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: The method of estimating lifetimes of aircraft devices operating under ageing-attributable wearing conditions
Autorzy:: Ważny, M.
Powiązania:: https://bibliotekanauki.pl/articles/281271.pdf
Data publikacji:: 2015
Wydawca:: Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:: reliability
lifetime
destructive processes
permissible condition
Opis:: The paper presents a probabilistic method of assessing lifetimes of selected structural components or assemblies of devices/systems affected by destructive processes that occur during aircraft operation. Reliability status of the device is evaluated by means of diagnostic or operational parameters. It is assumed that these devices (systems, assemblies) operate reliably if effects of wear and tear processes described by diagnostic parameters do not exceed boundary conditions/regimes. From the mathematical aspect, the method has been based on difference equations from which, when rearranged, a partial differential equation of the Fokker-Planck type is derived. A density function of the component wearing is a particular solution to this equation. With the density function of the component wearing applied, after suitable rearrangements, one can determine a density function of time for the exceeding the boundary condition. Now, with the density function of time of reaching the boundary condition found, and after rearrangement of this function, one receives dependences that can be applied to determine lifetime of the device given consideration. An example at the end of the paper illustrates how this method can be applied to analyse an airborne sighting system.
Źródło:: Journal of Theoretical and Applied Mechanics; 2015, 53, 4; 981-990
1429-2955
Pojawia się w:: Journal of Theoretical and Applied Mechanics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Resonance production in heavy ion collisions
Autorzy:: Markert, Ch.
Powiązania:: https://bibliotekanauki.pl/articles/146392.pdf
Data publikacji:: 2004
Wydawca:: Instytut Chemii i Techniki Jądrowej
Tematy:: resonance
strangeness
baryon
freeze-out
lifetime
fireball
Opis:: Resonances and their decay products may interact strongly with the hadrons in the fireball medium from the time of chemical freeze-out until the system breaks up at kinetic freeze-out. In order to try to further our understanding of the evolution and expansion of this hot and dense medium we compare resonance particle yields and spectra from elementary p+p and heavy ion collisions.
Źródło:: Nukleonika; 2004, 49,suppl.2; 119-123
0029-5922
1508-5791
Pojawia się w:: Nukleonika
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:: A model for service life control of selected device systems
Autorzy:: Zieja, M.
Ważny, M.
Powiązania:: https://bibliotekanauki.pl/articles/259281.pdf
Data publikacji:: 2014
Wydawca:: Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:: reliability
unreliability
durability
service lifetime
destructive processes
Opis:: This paper presents a way of determining distribution of limit state exceedence time by a diagnostic parameter which determines accuracy of maintaining zero state. For calculations it was assumed that the diagnostic parameter is deviation from nominal value (zero state). Change of deviation value occurs as a result of destructive processes which occur during service. For estimation of deviation increasing rate in probabilistic sense, was used a difference equation from which, after transformation, Fokker-Planck differential equation was obtained [4, 11]. A particular solution of the equation is deviation increasing rate density function which was used for determining exceedance probability of limit state. The so-determined probability was then used to determine density function of limit state exceedance time, by increasing deviation. Having at disposal the density function of limit state exceedance time one determined service life of a system of maladjustment. In the end, a numerical example based on operational data of selected aircraft [weapon] sights was presented. The elaborated method can be also applied to determining residual life of shipboard devices whose technical state is determined on the basis of analysis of values of diagnostic parameters.
Źródło:: Polish Maritime Research; 2014, 2; 45-49
1233-2585
Pojawia się w:: Polish Maritime Research
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:: A Survey of Multi-Objective Deployment in Wireless Sensor Networks
Autorzy:: Marks, M.
Powiązania:: https://bibliotekanauki.pl/articles/308483.pdf
Data publikacji:: 2010
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Tematy:: coverage
lifetime
placement
positioning
wireless sensor network
Opis:: The major challenge in designing wireless sensor networks (WSNs) is to find tradeoff between the desired and contrary requirements for the lifetime, coverage or cost while coping with the computation, energy and communication constraints. This paper examines the optimal placement of nodes for a WSN. It is impossible to consider the deployment of the nodes separately from WSNs applications. We highlight the properties of WSNs applications that determine the placement problem. We identify and enumerate the various objectives that should be considered. The paper provides an overview and concentrates on multi-objective strategies, their assumptions, optimization problem formulation and results.
Źródło:: Journal of Telecommunications and Information Technology; 2010, 3; 36-41
1509-4553
1899-8852
Pojawia się w:: Journal of Telecommunications and Information Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 8.

Tytuł:: Fluorescence decay time distribution analysis of cyclic enkephalin analogues; Influence of solvent and Leu configuration in position 5 on conformation
Autorzy:: Malicka, Joanna
Ganzynkowicz, Robert
Groth, Małgorzata
Czaplewski, Cezary
Karolczak, Jerzy
Liwo, Adam
Wiczk, Wiesław
Powiązania:: https://bibliotekanauki.pl/articles/1044169.pdf
Data publikacji:: 2001
Wydawca:: Polskie Towarzystwo Biochemiczne
Tematy:: lifetime distribution
fluorescence
energy transfer
conformation
enkephalin
Opis:: Lifetime distribution analysis were performed to study the influence of Leu configuration in position 5 on changes of the peptide chain of cyclic analogues of enkephalins containing a fluorescence donor and acceptor in different solvents. The configuration change of Leu5 in all the analogues of enkephalins studied which contain donor-acceptor pairs has no apparent influence on Trp lifetime distributions. In contrast, there is a significant solvent effect on the shape of lifetime distribution.
Źródło:: Acta Biochimica Polonica; 2001, 48, 1; 95-102
0001-527X
Pojawia się w:: Acta Biochimica Polonica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 9.

Tytuł:: Methods and algorithms for evaluating unknown parameters of components reliability of complex technical systems
Autorzy:: Kołowrocki, K.
Soszyńska, J.
Powiązania:: https://bibliotekanauki.pl/articles/2069673.pdf
Data publikacji:: 2009
Wydawca:: Uniwersytet Morski w Gdyni. Polskie Towarzystwo Bezpieczeństwa i Niezawodności
Tematy:: reliability
safety
lifetime
distribution
estimation
maritime transport
Opis:: The paper objectives are to present the methods and tools useful in the statistical identifying the unknown parameters of the components reliability and safety of complex industrial systems and to apply them in the maritime industry. There are presented statistical methods of estimating the unknown intensities of departure from the reliability state subsets of the exponential distribution of the component lifetimes of the multistate systems operating in various operation states. The goodness-of-fit method applied to testing the hypotheses concerned with the exponential form of the multistate reliability function of the particular components of the complex technical system in variable operations conditions is suggested. An application of these tools to reliability characteristics of a ferry operating at the Baltic Sea waters is presented as well.
Źródło:: Journal of Polish Safety and Reliability Association; 2009, 2; 223--230
2084-5316
Pojawia się w:: Journal of Polish Safety and Reliability Association
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 10.

Tytuł:: Low energy electrons in non-polar liquids
Autorzy:: Schmidt, W.
Illenberger, E.
Powiązania:: https://bibliotekanauki.pl/articles/148513.pdf
Data publikacji:: 2003
Wydawca:: Instytut Chemii i Techniki Jądrowej
Tematy:: electrons
energetics
kinetics
non-polar liquids
lifetime
Opis:: The properties of excess electrons in non-polar liquids have been studied for more than 30 years. Here, pertinent results are reviewed and discussed with respect to the possibility of studying electron-molecule interactions with low energy electrons in the liquid phase. Some new results on the estimate of the electron lifetime in the delocalized state in liquid hydrogen are presented.
Źródło:: Nukleonika; 2003, 48, 2; 75-82
0029-5922
1508-5791
Pojawia się w:: Nukleonika
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 11.

Tytuł:: How to support development of wise personality over lifetime? Review of The Wisdom of the Personality. Life Course Facilitation of Personality Development and Prevention of Personality Disorders by Helena Janet Grzegołowska-Klarkowska
Autorzy:: Kamila, Dobrenko,
Powiązania:: https://bibliotekanauki.pl/articles/896686.pdf
Data publikacji:: 2020-07-09
Wydawca:: Akademia Pedagogiki Specjalnej im. Marii Grzegorzewskiej. Wydawnictwo APS
Tematy:: support development of wise personality over lifetime
Opis:: Review of The Wisdom of the Personality. Life Course Facilitation of Personality Development and Prevention of Personality Disorders by Helena Janet Grzegołowska-Klarkowska
Źródło:: Psychologia Wychowawcza; 2020, 59(17); 223-238
0033-2860
Pojawia się w:: Psychologia Wychowawcza
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 12.

Tytuł:: Measurement the Thermal Profile of Steelmaking Ladle with Subsequent Evaluation the Reasons of Lining Damage
Autorzy:: Vlček, J.
Jančar, D.
Burda, J.
Klárová, M.
Velička, M.
Machovčák, P.
Powiązania:: https://bibliotekanauki.pl/articles/354815.pdf
Data publikacji:: 2016
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: ladle
refractory lining
temperature
enthalpy
ladle lifetime
Opis:: Based on the operational measurement, of which content was to determine ladle thermal profile, there were analysed causes of possible damage of lining in steel ladles by steel breakout through the ladle shell. There exists connection between thermal state of ladle lining during the operation and its lifetime. There were reached to the conclusion that the cause of failure in the lining of ladle is except for high temperature of bath, also wide interval of temperature change during the tap operation, in consequence with possible insufficient pre-heating of ladle, discontinuous operation of aggregate and damage of insulating lining layer, respectively deformation of ladles shell.
Źródło:: Archives of Metallurgy and Materials; 2016, 61, 1; 279-282
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 13.

Tytuł:: Uwarunkowania braku partnera życiowego w percepcji młodych dorosłych żyjących w pojedynkę
Autorzy:: Palus, Katarzyna
Powiązania:: https://bibliotekanauki.pl/articles/637325.pdf
Data publikacji:: 2011
Wydawca:: Uniwersytet Jagielloński. Wydawnictwo Uniwersytetu Jagiellońskiego
Tematy:: young adulthood, lifetime partner, singlehood, narrative-biographical interview
Opis:: The conditions of the lack of a lifetime partner in young adult singles’ perception The research field of this paper are the conditions of the lack of a lifetime partner in young adulthood. This research so called narrative-biographical interviews designed by Schütze was conducted with 36 participants not having partners (22 women and 14 men) in the age of 21–30 years. The foundation of the analysis was (1) Schütze’s narrative analysis and (2) hermeneutic analysis of autonarration used in the Bartosz’s research over motherhood. In the result of analysis participants’ responses were grouped into six categories of reasons for being single. Referring to respondents’ language they were called as follows: (1) “I haven’t met the right person yet”, (2) “I need time to recover from the break up”, (3) “My shyness stands in the way”, (4) “He/she doesn’t want me”, (5) “I’m a loner”, (6) “I work a lot”. The research results let us formulate the following general conclusions: (1) young adults indicate various reasons for being singled and which are of external and internal character and (2) in most cases young adults admit that it is hard to identify only one reason for singlehood which is often the consequence of many tangled circumstances.
Źródło:: Psychologia Rozwojowa; 2011, 16, 1
1895-6297
2084-3879
Pojawia się w:: Psychologia Rozwojowa
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 14.

Tytuł:: The Influence of the Base Material Parameters on Quantum and Photoconversion Efficiency of the Si Solar Cells
Autorzy:: Panek, P.
Powiązania:: https://bibliotekanauki.pl/articles/352268.pdf
Data publikacji:: 2016
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: silicon solar cell
dopant level
charge carrier lifetime
Opis:: The influence of a p-type Si with different resistivity, charge carrier lifetime and emitter dopant impurities concentration on the crystalline silicon solar cells parameters were analyzed and experimentally checked. The findings were determined by quasi-steady-state photoconductance, current-voltage and spectral response methods. The study was accompanied by solar device simulation using a numerical PC1D program. The highest photoconversion efficiency of 15.13 % was obtained for the moncrystalline (Cz-Si) solar cell with a base resistivity of 1.8 Ωcm and an effective charge carrier lifetime of 22.9 μs. The results clearly confirmed the importance concerning the dopant level in a Si base material in relation to open circuit voltage and short circuit current possible to obtain from the solar cell. Reduction of a base material resistivtiy leads to a lower value of an effective charge carrier lifetime and photoconversion efficiency both for Cz-Si and multicrystalline (mc-Si) solar cells. The experimental results and calculation showed, that in the case of a solar cell produced on the basis of crystalline silicon, the most important spectral range for an efficiency of a cell is covering a wavelength range of 587 ÷ 838 nm.
Źródło:: Archives of Metallurgy and Materials; 2016, 61, 4; 1889-1894
1733-3490
Pojawia się w:: Archives of Metallurgy and Materials
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 15.

Tytuł:: Application of the strain energy density parameter for estimation of multiaxial fatigue life of sintered steels with stress concentrators
Zastosowanie parametru gęstości energii odkształceń do oceny wieloosiowego zmęczenia stali spiekanych z koncentratorami naprężeń
Autorzy:: Łagoda, T.
Sonsino, C. M.
Ogonowski, P.
Powiązania:: https://bibliotekanauki.pl/articles/280271.pdf
Data publikacji:: 2009
Wydawca:: Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:: energy models
cyclic loading
fatigue lifetime
sintered steel
Opis:: This paper presents fatigue test results of a Fe-Cu sintered alloy (1.5% Cu) and three types of Fe-Cu-Ni sintered alloys (2% Cu, 2.5% Ni). Fe-Cu-Ni sintered alloys were produced under different compaction pressures and sintering temperatures. Round specimens with fillet notches were subjected to a constant amplitude pure bending, pure torsion and a combined in-phase and out-of-phase ( = 90.) bending with torsion. All results have been described by the criterion of the strain energy density parameter on the critical plane. It was assumed that the fatigue life is influenced by a linear combination of normal and strain energy density parameters with the coefficients that refer to the calculated plane. In particular, it allowed one to compute fatigue lives sufficiently comparable to the experimental ones.
W pracy przedstawiono rezultaty badań zmęczeniowych spieku Fe-Cu o zawartości 1.5% miedzi oraz trzech rodzajów spieku Fe-Cu-Ni o zawartości 2% miedzi i 2.5% niklu. Do badań zastosowano próbki okrągłe z koncentratorami naprężeń w postaci odsadzenia. Zakres badań obejmował stałoampitudowe zginanie, skręcanie oraz kombinacje proporcjonalnego i nieproporcjonalnego zginania ze skręcaniem. Wyniki badań eksperymentalnych zostały opisane przy zastosowaniu kryterium parametru energetycznego, opartego na koncepcji płaszczyzny krytycznej. Trwałość zmęczeniowa została wyznaczona na podstawie liniowej kombinacji parametru gęstości energii odkształceń normalnych oraz stycznych z pewnymi współczynnikami w przyjętej płaszczyźnie krytycznej. W większości przypadków otrzymano zadowalającą zgodność trwałości obliczeniowych z eksperymentalnymi.
Źródło:: Journal of Theoretical and Applied Mechanics; 2009, 47, 1; 161-175
1429-2955
Pojawia się w:: Journal of Theoretical and Applied Mechanics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 16.

Tytuł:: The influence of hydrogen concentration on positron lifetime and electrical resistivity in vanadium-hydrogen systems
Autorzy:: Pietrzak, R.
Szatanik, R.
Powiązania:: https://bibliotekanauki.pl/articles/146289.pdf
Data publikacji:: 2010
Wydawca:: Instytut Chemii i Techniki Jądrowej
Tematy:: positron lifetime
resistivity
V-H system
annihilation parameters
Opis:: Positron lifetime spectra and electrical resistivity of the vanadium-hydrogen systems with hydrogen concentration ranging from 0 to 0.29 at.H/at.V have been investigated. The range of hydrogen concentrations under investigation included the single alfa phase and a mixture of the alfa and beta phases of V-H system. The registered positron lifetime spectra were analysed by decomposition into two components. A distinct change in the annihilation parameters has been found after exceeding the boundary concentration of hydrogen in vanadium corresponding to the phase transition alfa (alfa+ beta). Correlation of changes in the parameters of the positron lifetime spectrum and in the electrical resistivity resulting from the changes in hydrogen concentration, has been revealed.
Źródło:: Nukleonika; 2010, 55, 1; 35-39
0029-5922
1508-5791
Pojawia się w:: Nukleonika
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 17.

Tytuł:: Evaluation of the durability of selected LED lamps
Autorzy:: Zalesińska, Małgorzata
Zabłocka, Julita
Pawlak, Andrzej
Powiązania:: https://bibliotekanauki.pl/articles/135480.pdf
Data publikacji:: 2020
Wydawca:: Akademia Morska w Szczecinie. Wydawnictwo AMSz
Tematy:: lifetime
LED lamps
non-directional LED lamps for household use
Ulbricht’s sphere
forecasting the luminous flux reduction
forecasted lifetime
Opis:: Luminous flux reduction during operation affects the operating lifetimes of LED lamps. Due to the very long lifetimes of LED sources, i.e. tens of thousands of hours, the lifetime declared by the manufacturer is most often determined by forecasting the luminous flux reduction. Lifetime forecasting is performed based on measuring the operating luminous flux reduction within a time frame of at least 6000 hours, every 1000 hours, followed by extrapolating the obtained results with a relevant exponential curve. This article presents the results of measurements of luminous flux changes taking place between 0 and 10,000 operating hours of several LED light sources. The obtained results were analyzed, and the lifetimes of the examined lamps were evaluated.
Źródło:: Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2020, 61 (133); 23-28
1733-8670
2392-0378
Pojawia się w:: Zeszyty Naukowe Akademii Morskiej w Szczecinie
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 18.

Tytuł:: Funkcjonowanie modelu sprzedażowego equity release w Polsce
Functioning of the sale model equity release in Poland
Autorzy:: Buzałek, Przemysław
Powiązania:: https://bibliotekanauki.pl/articles/653501.pdf
Data publikacji:: 2019
Wydawca:: Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:: świadczenia dożywotnie
renta dożywotnia
umowa dożywocia
odwrócony kredyt hipoteczny
fundusze hipoteczne
lifetime benefits
lifetime pension
life contract
reverse mortgage
mortgage funds
Opis:: The aim of the article is to present the fuctioning of the sale model equity release in Poland. While analyzing lifetime benefits concluded with elderly people the autor noticed that the market of sale model equity release in Poland needs new legal regulations. Current law regulations are not enough to protect the interest of elderly people.
Artykuł traktuje o funkcjonowaniu modelu sprzedażowego equity release w Polsce. Wskazane są w nim podstawowe różnice między odwróconym kredytem hipotecznym a świadczeniami dożywotnimi, scharakteryzowane są umowy, w ramach których zawierane są świadczenia dożywotnie, opisana jest sytuacja na rynku w latach 2010–2017, a także zidentyfikowane są podstawowe problemy wynikające z braku odrębnych regulacji prawnych.
Źródło:: Finanse i Prawo Finansowe; 2019, 1, 21; 11-26
2391-6478
2353-5601
Pojawia się w:: Finanse i Prawo Finansowe
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 19.

Tytuł:: Gas turbine reliability model based on tangent hyperbolic reliability function
Autorzy:: Djeddi, A. Z.
Hafaifa, A.
Salam, A.
Powiązania:: https://bibliotekanauki.pl/articles/280120.pdf
Data publikacji:: 2015
Wydawca:: Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:: reliability estimation
reliability algorithms
lifetime distribution
Weibull distribution
availability
Opis:: The present work deals with the exploration of a new model proposed for the reliability analysis of industrial production systems. This proposed model is mainly based on the tangent hyperbolic function, where the survival function is determined and used in the lifetime distribution modeling taking into account of estimation the parameters of the proposed function. On the other side, tests validation is performed using the real data of a gas turbine installation. The obtained results allow the modeling of damage effects, hence the prediction of the performance of the examined gas turbine using the proposed model gives good results in terms of validity.
Źródło:: Journal of Theoretical and Applied Mechanics; 2015, 53, 3; 723-730
1429-2955
Pojawia się w:: Journal of Theoretical and Applied Mechanics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 20.

Tytuł:: Research on preventive maintenance strategies and systems for in-service ship equipment
Autorzy:: Song, Tingxin
Tan, Taiyang
Han, Guochen
Powiązania:: https://bibliotekanauki.pl/articles/32887248.pdf
Data publikacji:: 2022
Wydawca:: Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:: preventive maintenance
FMEA
lifetime prediction
decision system
ship equipment
Opis:: With continuous improvements in the function and performance of ship equipment, mechanisms of failure have become more and more complicated. To avoid over-maintenance or under-maintenance in existing routine ship maintenance strategies, a ship-level method for repair decisions based on the preventive maintenance concept is proposed in this paper. First, the anticipated repair demand levels of key components are calculated using an improved failure mode and effects analysis (FMEA) method; second, a Weibull distribution model is established, and the parameters are estimated using the maximum likelihood estimation (MLE) to predict the characteristic life of the equipment; then, logical decision principles and rule-based reasoning (RBR) are used to determine the ship repair level and repair timing. Finally, the feasibility and application value of the proposed repair strategy were verified by case studies, and a ship-level system for repair decisions was established.
Źródło:: Polish Maritime Research; 2022, 1; 85-96
1233-2585
Pojawia się w:: Polish Maritime Research
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 21.

Tytuł:: Performance Evaluation of a Zone-based Three-level Heterogeneous Clustering Protocol for WSNs
Autorzy:: Rao, Sanapala Shanmukha
Shilpi
Kumar, Arvind
Powiązania:: https://bibliotekanauki.pl/articles/24200745.pdf
Data publikacji:: 2023
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Tematy:: clustering
heterogeneous
network lifetime
stability period
zone-based WSN
Opis:: This paper proposes a zone-based three-level heterogeneous clustering protocol (ZB-TLHCP) for heterogeneous WSNs. In ZB-TLHCP, the sensor field/region is divided into zones where super, advance, and normal nodes are deployed uniformly and randomly. The performance of the proposed ZB-TLHCP system is compared with that of zonal-stable election protocol (Z-SEP), distributed energy efficient clustering (DEEC), and threshold-based DEEC (TDEEC) protocol by varying the number of super and advance nodes, their energy levels for the fixed sensor field, and the total number of nodes. Matlab simulation results revealed that the proposed ZB-TLHCP solution performed better than Z-SEP, DEEC, and TDEEC protocols, as it increased the instability period, prolonged the network's lifetime, and achieved higher throughput values.
Źródło:: Journal of Telecommunications and Information Technology; 2023, 3; 85--93
1509-4553
1899-8852
Pojawia się w:: Journal of Telecommunications and Information Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 22.

Tytuł:: A method for estimating the probability distribution of the lifetime for new technical equipment based on expert judgement
Autorzy:: Andrzejczak, Karol
Bukowski, Lech
Powiązania:: https://bibliotekanauki.pl/articles/2038033.pdf
Data publikacji:: 2021
Wydawca:: Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:: uncertainty
expert elicitation of lifetime
quantile function
Weibull distribution
Opis:: Managing the exploitation of technical equipment under conditions of uncertainty requires the use of probabilistic prediction models in the form of probability distributions of the lifetime of these objects. The parameters of these distributions are estimated with the use of statistical methods based on historical data about actual realizations of the lifetime of examined objects. However, when completely new solutions are introduced into service, such data are not available and the only possible method for the initial assessment of the expected lifetime of technical objects is expert methods. The aim of the study is to present a method for estimating the probability distribution of the lifetime for new technical facilities based on expert assessments of three parameters characterizing the expected lifetime of these objects. The method is based on a subjective Bayesian approach to the problem of randomness and integrated with models of classical probability theory. Due to its wide application in the field of maintenance of machinery and technical equipment, a Weibull model is proposed, and its possible practical applications are shown. A new method of expert elicitation of probabilities for any continuous random variable is developed. A general procedure for the application of this method is proposed and the individual steps of its implementation are discussed, as well as the mathematical models necessary for the estimation of the parameters of the probability distribution are presented. A practical example of the application of the developed method on specific numerical values is also presented.
Źródło:: Eksploatacja i Niezawodność; 2021, 23, 4; 757-769
1507-2711
Pojawia się w:: Eksploatacja i Niezawodność
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 23.

Tytuł:: Hybrid reliability modelling under general uncertainty
Autorzy:: Guo, R.
Cui, Y.
Thiart, C.
Guo, D.
Powiązania:: https://bibliotekanauki.pl/articles/2069636.pdf
Data publikacji:: 2010
Wydawca:: Uniwersytet Morski w Gdyni. Polskie Towarzystwo Bezpieczeństwa i Niezawodności
Tematy:: uncertain measure
hybrid lifetime
uncertain parameter
average chance reliability
Opis:: The real world phenomena are often facing the co-existence reality of different formality of uncertainty and thus the probabilistic reliability modeling practices are very doubtful. Under complicated uncertainty environments, hybrid variable modeling is important in reliability and risk analysis, which includes Bayesian distributional theory, random fuzzy distributional theory, as well as fuzzy random distributional theory as special distribution families. In this paper, we define a new hybrid lifetime which is specified by a random lifetime distribution with an uncertain distributed parameter, which is called as random uncertain hybrid lifetime. We furthermore define the average chance distribution as a quality index for quantifying the hybrid lifetime and accordingly the average chance reliability is derived.
Źródło:: Journal of Polish Safety and Reliability Association; 2010, 1, 1; 115--122
2084-5316
Pojawia się w:: Journal of Polish Safety and Reliability Association
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 24.

Tytuł:: Technological solutions to extend the operating cycle of tools and industrial machinery
Autorzy:: Lukarski, Y.
Tashev, P.
Argirov, C.
Kondov, H.
Powiązania:: https://bibliotekanauki.pl/articles/391484.pdf
Data publikacji:: 2017
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Odlewnictwa
Tematy:: operational lifetime
new materials
overlay welding
thermo-chemical treatment
Opis:: One of the most significant problems that engineers and researchers face is the development of technological solutions to extend the exploitation cycle of tools and industrial machinery. The research shows there are a few possibilities to solve this problem: 1. Development of new materials of enhanced working characteristics compared to those currently used. An example of this is the introduction of new metals and alloys in the automotive industry, the mining industry, etc. 2. Preventive processing of assemblies and parts prior to their use consisting mainly in overlay welding with wear resistant layers or thermo-chemical surface treatment of the parts. 3. Recovering assemblies and parts after their resource has been depleted. This is mainly applied in the mining industry, road construction, etc. Worn-out tools are overlay welded and reused. It has been proven that the price of the recovered details is 2 to 20 times lower than that of the new ones. Moreover, it should be pointed out that the recovery saves energy and ore resources and thus a significant environmental impact is achieved.
Źródło:: Prace Instytutu Odlewnictwa; 2017, 57, 4; 253-258
1899-2439
Pojawia się w:: Prace Instytutu Odlewnictwa
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 25.

Tytuł:: Identification of heredity kernels and their influence on the life time of glass/polyester composites
Autorzy:: Olodo, E. T.
Adjovi, E. C.
Adanhounme, V.
Powiązania:: https://bibliotekanauki.pl/articles/955255.pdf
Data publikacji:: 2014
Wydawca:: Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:: lepkosprężystość
parametry sprężyste
kompozyty
heredity kernels
viscoelastic parameters
lifetime
Opis:: One of the major problems encountered in prediction of hereditary viscoelastic behavior of polymeric composites is the determination of heredity kernels. This issue comes down to identification of the model characterizing the viscoelastic properties of these materials. The purpose of this work is to propose a model for prediction of viscoelastic nonlinear behavior of laminate composite with polyester matrix, through the study and analysis of heredity kernels and their influence on the life time of this material. Identification of this model required experimental determination at room temperature, of viscoelastic parameters of heredity kernels by macroscopic approach. These data provide predictive tools for establishment of the life time and long term stress limit under static complex loading for this type of material.
Źródło:: International Journal of Applied Mechanics and Engineering; 2014, 19, 4; 725-734
1734-4492
2353-9003
Pojawia się w:: International Journal of Applied Mechanics and Engineering
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 26.

Tytuł:: Kompetencje relacyjne młodych dorosłych nieposiadających i posiadających partnera życiowego
Autorzy:: Adamczyk, Katarzyna
Powiązania:: https://bibliotekanauki.pl/articles/637382.pdf
Data publikacji:: 2012
Wydawca:: Uniwersytet Jagielloński. Wydawnictwo Uniwersytetu Jagiellońskiego
Tematy:: lifetime partner
partnered life
relational competences
single life
young adulthood
Opis:: The review of literature and studies let us suppose that a definite level of relational competences create greater or less possibilities to find a lifetime partner, and to maintain a relationship with him or her. In the article the findings of the research with 457 young single and partnered adults are presented. Their aim was to verify whether are there any differences between young single and partnered adults in the extent of level of relational competences, which indices were five six bonding behaviours (behaviours of psychic and physical closeness, impressive behaviours, behaviours on the behalf of a partner and a relationship, conciliatory behaviours, and sexual behaviours). Additionaly an association between level of relational competences and gender was analysed. It was assumed that lower level of competences will be characteristic of single adults. Moreover, it was hypothesized that females will possess a higher level of competences in comparison to males. Statistical analysis showed that the observed difference between single and partnered groups in the area of relational competences is statistically significant. Single individuals reveal a lower level of relational competences in the realm of the above-mentioned bonding behaviours. At the same time, gender showed to be a differentiating factor only in the area of competences concerned behaviours of psychic and physical closeness, and sexual behaviours.
Źródło:: Psychologia Rozwojowa; 2012, 17, 2; 87-100
1895-6297
2084-3879
Pojawia się w:: Psychologia Rozwojowa
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 27.

Tytuł:: Optimal credit period and ordering quantity for credit dependent trended demand and deteriorating items with maximum lifetime
Autorzy:: Shah, N. H.
Shah, D. B.
Patel, D. G.
Powiązania:: https://bibliotekanauki.pl/articles/970075.pdf
Data publikacji:: 2015
Wydawca:: Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:: inventory
trended demand
trade credit
default risk
deterioration
maximum lifetime
Opis:: In this paper, an inventory system is analyzed regarding a trended demand. The seller oﬀers its buyer a credit period for settling the account, which attracts more buyers and enhances market demand. However, the oﬀer of credit period leads to default risk for the supplier. The units in inventory are deteriorating continuously and also have deﬁnite maximum lifetime. The aim is to maximize the proﬁt of the retailer. Numerical examples are given to validate the developed mathematical model. Sensitivity analysis is performed to obtain the critical inventory parameters and deduce the managerial strategies.
Źródło:: Control and Cybernetics; 2015, 44, 2; 311-320
0324-8569
Pojawia się w:: Control and Cybernetics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 28.

Tytuł:: Lifetime distributions with wave-like bathtub hazard
Autorzy:: Guo, R.
Thiart, C.
Cui, Y.
Guo, D.
Powiązania:: https://bibliotekanauki.pl/articles/2069543.pdf
Data publikacji:: 2011
Wydawca:: Uniwersytet Morski w Gdyni. Polskie Towarzystwo Bezpieczeństwa i Niezawodności
Tematy:: lifetime distribution
hazard
bathtub hazard
likelihood function
maximum likelihood estimation
Opis:: In this paper, we argue the necessity of dealing with lifetime distributions with wave-like bathtub hazard function. Four classes of wave-like bathtub hazards are investigated. For preparing maximum likelihood estimation of the hazard parameters, the first-order and second-order partial derivatives are derived.
Źródło:: Journal of Polish Safety and Reliability Association; 2011, 2, 1; 115--122
2084-5316
Pojawia się w:: Journal of Polish Safety and Reliability Association
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 29.

Tytuł:: The Weibull lifetime model with randomised failure-free time
Autorzy:: Sulewski, Piotr
Szymkowiak, Magdalena
Powiązania:: https://bibliotekanauki.pl/articles/2156948.pdf
Data publikacji:: 2022-12-15
Wydawca:: Główny Urząd Statystyczny
Tematy:: Weibull lifetime model
randomised failure-free time
compound Weibull distributions
Opis:: The paper shows that treating failure-free time in the three-parameter Weibull distribution not a constant, but as a random variable makes the resulting distribution much more flexible at the expense of only one additional parameter.
Źródło:: Statistics in Transition new series; 2022, 23, 4; 59-76
1234-7655
Pojawia się w:: Statistics in Transition new series
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 30.

Tytuł:: Scheduling Based Wireless Sensor Networks Integrated with IoT Environment
Autorzy:: Mahendran, N.
Powiązania:: https://bibliotekanauki.pl/articles/1193556.pdf
Data publikacji:: 2016
Wydawca:: Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:: Data Scheduling Schemes
Energy Efficient
IoT
Network lifetime
Sensor Network
Opis:: Wireless Sensor networks are widely adopt in military, target tracking, signal processing and monitoring applications like traffic and structural, the small and low cost unreliable sensor nodes in these applications uses batteries as the sole energy source. The energy efficiency becomes difficult task as the tiny and less weight battery act as source of each node. Scheduling the different category of data packets is a way to reduce the power consumption and increasing the lifetime of sensor nodes. The existing scheduling algorithms are not adapted to the environment changes. The basic FCFS (First Come First Serve) suffered by long delay while transmit the real time data packets. In DMP (Dynamic Multilevel Priority) real time data packets occupies highest priority, the remaining non real time data packets sent to lower priority level queues. Some real time task holds the resources for longer time, the other task have to wait, it makes the deadlock condition. The NJN (Nearest Job Next) will select the nearest requesting sensor node for service, real time packets have to wait long time. The proposed Adaptive weighted scheduling scheme changes the behavior of the network queue by adaptively changes the weights based on network traffic. Simulation results proof that, adaptive weighted scheduling algorithm works better than the FCFS and DMP data scheduling in terms of energy consumption and lifetime. Our future scheme to integrate Internet of Things (IoT) with the WSN to increase the performance of the wireless networks.
Źródło:: World Scientific News; 2016, 41; 116-127
2392-2192
Pojawia się w:: World Scientific News
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 31.

Tytuł:: EEULA: an energy-aware event-driven unicast algorithm for wireless sensor network by learning automata
Autorzy:: Kashani, A. A. S.
Noori, A. M. M.
Powiązania:: https://bibliotekanauki.pl/articles/102180.pdf
Data publikacji:: 2016
Wydawca:: Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:: network lifetime
wireless sensor network
learning automata
energy efficiency algorithm
Opis:: Energy consumption is one of the major challenges in wireless sensor networks, thus necessitating an approach for its minimization and for load balancing data. The network lifetime ends with the death of one of its nodes, which, in turn, causes energy depletion in and partition of the network. Furthermore, the total energy consumption of nodes depends on their location; that is, because of the loaded data, energy discharge in the nodes close to the base station occurs faster than other nodes, the model presented here, through using learning automata, selects the path appropriate for data transferring; the selected path is rewarded or penalized taking the reaction of surrounding paths into account. We have used learning automata for energy management in finding the path; the routing protocol was simulated by NS2 simulator; the lifetime, energy consumption and balance in an event-driven network in our proposed method were compared with other algorithms.
Źródło:: Advances in Science and Technology. Research Journal; 2016, 10, 30; 9-18
2299-8624
Pojawia się w:: Advances in Science and Technology. Research Journal
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 32.

Tytuł:: Trwałość narzędzi w procesach kucia
Tool lifetime in forging processes
Autorzy:: Gronostajski, Z.
Kaszuba, M.
Hawryluk, M.
Nowak, B.
Powiązania:: https://bibliotekanauki.pl/articles/211705.pdf
Data publikacji:: 2015
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Obróbki Plastycznej
Tematy:: kucie
inżynieria powierzchni
trwałość
narzędzia
forging
surface engineering
lifetime
tools
Opis:: W artykule omówiono najważniejsze mechanizmy niszczące narzędzia w procesach kucia, takie jak: zużycie ścierne, zmęczenie cieplno-mechaniczne, odkształcenie plastyczne, pękanie zmęczeniowe, zużycie adhezyjne i utlenianie. Wykazano, że intensywność zużycia zmienia się wraz ze zmianą parametrów procesu lub miejsca na narzędziu, co jest zdeterminowane przez czas kontaktu pomiędzy matrycą i odkuwką oraz zmianami temperatury. Natomiast w literaturze wymienione zjawiska na ogół analizowane są oddzielnie i nie ma dokładnego opisu fizycznego procesu zużycia, uwzględniającego wszystkie zjawiska jednocześnie, jak ma to miejsce w rzeczywistości. Na podstawie analizy mechanizmów niszczących oraz warunków pracy narzędzi w procesach kucia na półgorąco i na gorąco, wyodrębniono trzy grupy czynników wpływających na trwałość narzędzi kuźniczych. Czynniki te związane są z narzędziem (rodzaj materiału, technologia wykonania, kształt, konstrukcja, jakość wykonania), z odkuwką (rodzaj materiału, kształt, temperatura początkowa przedkuwki, jakość powierzchni, tolerancja wymiarowa) oraz z eksploatacją (parametry procesu kucia, rodzaj maszyny, zastosowana technologia kucia). Omówiono również metodę poprawy trwałości narzędzi ze szczególnym uwzględnieniem technologii wykonania warstwy wierzchniej, gdzie obecnie duże perspektywy stwarzają metody hybrydowe obróbki powierzchniowej, polegające na zastosowaniu dwóch lub więcej technik inżynierii powierzchni w jednym procesie technologicznym. Najczęściej stosowanymi warstwami hybrydowymi są warstwy typu warstwa azotowana/powłoka PVD lub CVD. Dzięki połączeniu i wzajemnemu oddziaływaniu różnych technologii można uzyskać właściwości warstwy wierzchniej nieosiągalne przy zastosowaniu tych technik oddzielnie.
This article discusses the most important mechanisms of tool destruction in forging processes, such as: abrasive wear, thermomechanical fatigue, plastic deformation, fatigue cracking, adhesive wear, and oxidation. It is shown that the intensity of wear changes when process parameters or the location on the tool change, which is determined by the time of contact between the die and forging as well as by temperature changes. The aforementioned phenomena are generally analyzed separately in the literature, and there is no precise physical description of the wear process that accounts for all of these phenomena simultaneously, just as they occur in reality. Based on analysis of destructive mechanisms and tool working conditions in semi-hot and hot forging processes, three groups of factors with an influence on the lifetime of forging tools were distinguished. These factors are related to the tool (type of material, manufacturing technology, shape, design, quality of workmanship), to the forging (type of material, shape, initial preform temperature, surface quality, dimensional tolerance) and to the forging process (forging process parameters, machine type, applied forging technology). A method for improving tool lifetime is also discussed, with particular emphasis on technology for forming the surface layer, where hybrid surface methods based on the application of two or more surface engineering techniques in one technological process are currently creating many new possibilities. The most commonly applied hybrid layers are nitrided layer/PVD or CVD coating. Thanks to the combination and reciprocal interaction of different technologies, properties of the surface layer that are not attainable when these techniques are applied separately can be achieved.
Źródło:: Obróbka Plastyczna Metali; 2015, 26, 3; 255-270
0867-2628
Pojawia się w:: Obróbka Plastyczna Metali
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 33.

Tytuł:: Estimation of high temperature fatigue lifetime of SUS304 steel with an energy parameter in the critical plane
Ocena wysokotemperaturowej trwałości zmęczeniowej stali SUS304 za pomocą parametru energetycznego w płaszczyźnie krytycznej
Autorzy:: Łagoda, T.
Macha, E.
Sakane, M.
Powiązania:: https://bibliotekanauki.pl/articles/281113.pdf
Data publikacji:: 2003
Wydawca:: Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:: low-cycle fatigue
multiaxial fatigue
energy approach
lifetime
high temperature
Opis:: The paper studies the application of the energy parameter, a sum of elastic and plastic strain energy densities in the critical plane, for the correlation of two series of proportional biaxial low-cycle lives using SUS304 stainless steel at elevated temperature. The first data used thin-walled cylinder specimens subjected to 7 proportional strain paths of combined tension-torsion and the other used cruciform specimens subjected to 5 proportional strain paths of biaxial tension-compression. These tests were done at the temperature of 923 K. The normal total strain energy density in the plane with the maximum damage was a suitable parameter for describing the test results.
Praca dotyczy zastosowania parametru energetycznego, sumy gęstości energii sprężystej i plastycznej odkształcenia w płaszczyźnie krytycznej do korelacji dwóch serii proporcjonalnych, dwuosiowych, niskocyklowych trwałości zmęczeniowych stali nierdzewnej SUS303 w podwyższonej temperaturze.Badano cienkościenne próbki cylindryczne poddane siedmiu proporcjonalnym torom odkształcenia w warunkach kombinacji rozciągania-skręcania oraz próbki krzyżowe poddane pięciu proporcjonalnym torom odkształcenia w warunkach dwuosiowego rozciągania-ściskania. Badania prowadzono w temperaturze 923 K. Gęstość energii całkowitego odkształcenia normalnego w płaszczyźnie maksymalnego uszkodzenia była odpowiednim parametrem do opisania wyników badań.
Źródło:: Journal of Theoretical and Applied Mechanics; 2003, 41, 1; 55-73
1429-2955
Pojawia się w:: Journal of Theoretical and Applied Mechanics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 34.

Tytuł:: Zarządzanie wartością klienta na rynku usług medycznych w Polsce
The customer lifetime value management concerning medical services in Poland
Autorzy:: Nagraba, Katarzyna
Powiązania:: https://bibliotekanauki.pl/articles/446992.pdf
Data publikacji:: 2015
Wydawca:: Mazowiecka Uczelnia Publiczna w Płocku
Tematy:: Customer Lifetime Value
medical services
helath care
private medicine
hospitals
Opis:: The Customer Lifetime Value is crucial in every kind of economic activity as the customer is the good that brings profits to the companies. This is the main reason why entrepreneurs and managers should always think how to satisfy needs of its clients. One of markets, on which the customer value should be thoroughly analyzed is medicine. This article presents the theoretical basis of customer lifetime value management and tries to explain how it is being introduced on medical services market in Poland. As the health care in Poland seems to be on initial stage there is a lot of space for new, private medical centers to be set up. Majoroty of institution operates basing on concracts with National Health Fund (NFZ) and there are fully dependent from the amounts of money granted by the institution. It is renegotiated after certain period and there is always the risk of not winning it again. Unfortunately due to weaknesses of public health care system in Poland, many customers are disappointed with its quality and management form. In these conditions the private medicine services are improving. Unfortunately there is no possibility in choosing the form of health insurance (all are paying contribution to National Health Fund). In this case there is a hope for development of a competitive market, which would be certainly supported by private insurance. The artice is an introduction to deeper considerations regarding medicine in Poland and the effectiveness of managing medical centers (especially hospitals).
Źródło:: Zeszyty Naukowe PWSZ w Płocku. Nauki Ekonomiczne; 2015, 1(21); 115-127
1644-888X
Pojawia się w:: Zeszyty Naukowe PWSZ w Płocku. Nauki Ekonomiczne
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 35.

Tytuł:: Optimization of critical infrastructure operation and safety with considering climate-weather change influence : maximizing safety lifetime
Autorzy:: Kołowrocki, K.
Kuligowska, E.
Soszyńska-Budny, J.
Powiązania:: https://bibliotekanauki.pl/articles/2068785.pdf
Data publikacji:: 2018
Wydawca:: Uniwersytet Morski w Gdyni. Polskie Towarzystwo Bezpieczeństwa i Niezawodności
Tematy:: critical infrastructure
safety
operation process
climate-weather change
optimization
safety lifetime
Opis:: The method based on the results of the joint model linking a semi-Markov modelling of the critical infrastructure operation process with a multistate approach to critical infrastructure safety and linear programming are proposed to the critical infrastructure operation and safety optimization. This method determining the optimal values of limit transient probabilities at the critical infrastructure operation states that maximize the critical infrastructure safety lifetime in the safety state subsets is proposed.
Źródło:: Journal of Polish Safety and Reliability Association; 2018, 9, 1; 1--10
2084-5316
Pojawia się w:: Journal of Polish Safety and Reliability Association
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 36.

Tytuł:: Reliability concept under general uncertainty
Autorzy:: Guo, R.
Cui, Y.
Thiart, C.
Guo, D.
Powiązania:: https://bibliotekanauki.pl/articles/2069525.pdf
Data publikacji:: 2010
Wydawca:: Uniwersytet Morski w Gdyni. Polskie Towarzystwo Bezpieczeństwa i Niezawodności
Tematy:: probabilistic reliability
uncertain reliability
uncertain measure
uncertainty lifetime
uncertain hazard function
Opis:: The Toyota crisis is tearing off the brand image of quality and reliability and therefore it is logical to question whether the dominating position of probability theory, on which Japanese quality and reliability engineering practices are established, should be examined. In general, reliability analysis is an exercise under uncertain environment. Foundationally speaking, uncertain modeling is a matter of choosing what kind of uncertain measure as its standing point. In this paper, we introduce the uncertainty reliability concept on the platform of the axiomatic uncertain measure theory and compare it to probabilistic reliability concept based on Kolmogorov’s probability measure theory, on which the traditional quality and reliability engineering is established. It is expecting that a foundational work can be established for a more rigorous reliability engineering and risk analysis under general uncertainty environments.
Źródło:: Journal of Polish Safety and Reliability Association; 2010, 1, 1; 105--114
2084-5316
Pojawia się w:: Journal of Polish Safety and Reliability Association
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 37.

Tytuł:: On a general standby system and its optimization
Autorzy:: Cha, J. H.
Yun, W. Y.
Powiązania:: https://bibliotekanauki.pl/articles/2069693.pdf
Data publikacji:: 2009
Wydawca:: Uniwersytet Morski w Gdyni. Polskie Towarzystwo Bezpieczeństwa i Niezawodności
Tematy:: warm standby
accelerated life testing
virtual age
switching time
mean lifetime
Opis:: Redundancy or standby is a technique that has been widely applied to improving system reliability and availability in the stage of system design. In this paper, we consider a standby system with two units in which the first unit (unit 1) starts its operation under active state and the other unit (unit 2) is under cold standby state at the starting point. After a specified time s (switching time), the state of unit 2 is changed to warm standby state and, as soon as the operating unit 1 fails, the state of unit 2 is changed to active state. If unit 1 fails before times, the system fails. Units can fail at both active and warm standby states. A general method for modeling the standby system is adopted and, based on it, system performance measures (system reliability and mean life) are derived. We consider the problem of determining optimal switching time which maximizes the expected system life. Some numerical examples are studied.
Źródło:: Journal of Polish Safety and Reliability Association; 2009, 1; 95--100
2084-5316
Pojawia się w:: Journal of Polish Safety and Reliability Association
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 38.

Tytuł:: Positron annihilation lifetime spectroscopy study of thermal processing and rehydration of dry leek (Allium porrum L.)
Autorzy:: Zaleski, R.
Wawryszczuk, J.
Sobczak, K.
Powiązania:: https://bibliotekanauki.pl/articles/146309.pdf
Data publikacji:: 2010
Wydawca:: Instytut Chemii i Techniki Jądrowej
Tematy:: positron annihilation
lifetime spectroscopy
food processing
rehydration
leek (Allium porrum L.)
Opis:: New application of positron annihilation lifetime spectroscopy (PALS) to development of food processing techniques is tested. Dehydrated leeks were an object of the study. Three experiments were performed consisting of evacuating air and volatile compounds from the sample, applying thermal treatment and rehydrating the sample. Distinct changes in positron lifetime spectra allowed the monitoring of alterations in the sample structure. The most likely origin of the particular components present in the spectra was able to be proposed from these data. Changes of the components were ascribed to the various processes occurring in the samples.
Źródło:: Nukleonika; 2010, 55, 1; 73-78
0029-5922
1508-5791
Pojawia się w:: Nukleonika
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 39.

Tytuł:: On useful schema in survival analysis after heart attack
Autorzy:: Stępniak, Czesław
Powiązania:: https://bibliotekanauki.pl/articles/729744.pdf
Data publikacji:: 2014
Wydawca:: Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:: lifetime after heart attack
distribution
Fibonacci number
Lucas number
Pascal triangle
Opis:: Recent model of lifetime after a heart attack involves some integer coefficients. Our goal is to get these coefficients in simple way and transparent form. To this aim we construct a schema according to a rule which combines the ideas used in the Pascal triangle and the generalized Fibonacci and Lucas numbers
Źródło:: Discussiones Mathematicae Probability and Statistics; 2014, 34, 1-2; 63-69
1509-9423
Pojawia się w:: Discussiones Mathematicae Probability and Statistics
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 40.

Tytuł:: Fatigue lifetime correction of structural joints Indexed by: of opencast mining machinery
Autorzy:: Grabowski, Paweł
Jankowiak, Artur
Marowski, Witold
Powiązania:: https://bibliotekanauki.pl/articles/2038154.pdf
Data publikacji:: 2021
Wydawca:: Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:: fatigue life
lifetime assessment
supporting structure
welded joints
opencast mining machinery
Opis:: Opencast mining machinery represents a group of large-scale individually manufactured technical objects operated with long-life requests. Since their manufacturers are obliged to provide product that will reach declared time of life, fatigue strength and durability conditions have to be taken into account for superstructures to meet the requirements. The paper highlights main problems occurring while assessing fatigue lifetime during design. Firstly, the short survey of current state of the art regarding the approach to this problem is presented. Secondly, the most important reasons of unsatisfactory accuracy of the assessments are discussed. As a main objective of the study, the authors introduce the unique method of continuous fatigue lifetime correction for the welded superstructures during the machine lifecycle, as a remedy for this group of machinery. Furthermore, results and experience from adapting the approach in real object are presented, including fatigue lifetime correction due to the real intensity of loading acquired from a bucket-wheel excavator during its longlasting operation. It is expected that proposed procedure can help to improve credibility of fatigue lifetime assessment of heavy earthmoving machinery.
Źródło:: Eksploatacja i Niezawodność; 2021, 23, 3; 530-539
1507-2711
Pojawia się w:: Eksploatacja i Niezawodność
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 41.

Tytuł:: Lifetime performance evaluation model based on quick response thinking
Autorzy:: Chiou, Kuo-Ching
Chen, Kuen-Suan
Powiązania:: https://bibliotekanauki.pl/articles/2057979.pdf
Data publikacji:: 2022
Wydawca:: Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:: lifetime performance index
Type-II right censoring
UMVU estimators
UMP test
Opis:: In practice, lifetime performance index CL has been a method commonly applied to the evaluation of quality performance. L is the upper or lower limit of the specification. The product lifetime distribution is mostly abnormal distribution. This study explored that the lifetime of commodities comes from exponential distribution. Complete data collection is the primary goal of analysis. However, the censoring type is one of the most commonly used methods due to considerations of manpower and material cost or the timeliness of product launch. This study adopted Type-II right censoring to find out the uniformly minimum variance unbiased (UMVU) estimator of the lifetime performance index CL and its probability density function. Afterward this study obtained the 100×(1-α)% confidence interval of the lifetime performance index CL as well as created the uniformly most powerful (UMP) test and the power of the test for the product lifetime performance index. Last, this study came up with a numerical example to demonstrate the suggested method as well as the application of the model.
Źródło:: Eksploatacja i Niezawodność; 2022, 24, 1; 1--6
1507-2711
Pojawia się w:: Eksploatacja i Niezawodność
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 42.

Tytuł:: Improvement of enzyme stability via non-covalent complex formation with dextran against temperature and storage lifetime
Autorzy:: Altikatoglu, M.
Kuzu, H.
Powiązania:: https://bibliotekanauki.pl/articles/778394.pdf
Data publikacji:: 2010
Wydawca:: Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:: stabilizacja termiczna
enzymy
dekstran
thermal stabilization
complex
enzyme
dextran
storage lifetime
Opis:: The optimal methodology to prepare the novel modified enzyme, polymer-enzyme complex, was developed to give a high catalytic activity in aqueous solution. The non-covalent complexes of two different enzymes (horseradish peroxidase and glucose oxidase) were prepared with various molar ratios (nD/nE 0,05; 0,1; 1; 5; 10; 15; 20) by using 75kDa dextran. The thermal stabilities of the obtained complexes were evaluated with the activities determined at different temperatures (25, 30, 35, 40, 50, 60, 70, 80°C) applying 60 minutes incubation time for pH 7. The complexes with the molar ratio nD/nHRP: 10 and nD/nGOD: 5 showed the highest thermal stability. Its activity was very high (ca. 1,5-fold higher activity than pure enzyme for HRP-dextran complexes) and almost the same between applying one hour incubation time and without incubation, and could also be measured at high temperatures (70, 80 °C). We finally succeeded in preparing dextran-enzyme complexes which showed higher activity than pure enzyme in aqueos solution at all temperatures for pH 7. In addition, the mentioned complexes at pH 7 had very long storage lifetime compared to purified enzyme at +4 °C; which is considered as a good feature for the usage in practice.
Źródło:: Polish Journal of Chemical Technology; 2010, 12, 1; 12-16
1509-8117
1899-4741
Pojawia się w:: Polish Journal of Chemical Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 43.

Tytuł:: Influence of antifreeze proteins on local waters structure dynamics in presence of osmolytes
Autorzy:: Krishnamoorthy, A. N.
Powiązania:: https://bibliotekanauki.pl/articles/1933947.pdf
Data publikacji:: 2013
Wydawca:: Politechnika Gdańska
Tematy:: hydration dynamics
hydrogen bond lifetime
osmolytes
Kirkwood-Buff integrals
prefential binding parameter
Opis:: Antifreeze proteins are synthesized by various organisms to enable their cells to survive subzero environment in the arctic and polar regions. These proteins produce a difference between the melting and freezing points termed as thermal hysteresis. The main objective of this study is to examine the dynamics of water molecules and hydrogen bonds at the protein-water interface of antifreeze protein using atomistic molecular dynamics simulations using GROMACS. For this work a prototype of AFP (antifreeze protein) from antarctic notothenioids (ala-ala-thr repeats) and a mutant which is not antifreeze active were generated using PRODRG server. The hydration dynamics results revealed that the retarded water dynamics in the AFP compared to its mutant was responsible for the antifreeze activity. Furthermore a considerable increase in antifreeze activity were observed for the AFP in presence of osmolytes. The mechanism of action were tested using preferential binding parameter derived from Kirkwood-Buff integerals.
Źródło:: TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2013, 17, 1-2; 5-42
1428-6394
Pojawia się w:: TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 44.

Tytuł:: PALS investigation of resorcinol under high pressure
Autorzy:: Tydda, M.
Jasińska, B.
Pieniążek, A.
Powiązania:: https://bibliotekanauki.pl/articles/147999.pdf
Data publikacji:: 2013
Wydawca:: Instytut Chemii i Techniki Jądrowej
Tematy:: free volume
ortho-positronium (o-Ps)
pressure
positron annihilation lifetime spectroscopy (PALS)
Opis:: Two kinds of measurements were conducted with resorcinol at high pressure : the first one with the use of a mechanical press and the second one with the use of a gaseous compressor. In the second case, due to some gas penetrating the material structure, the lifetime spectra obtained were difficult to analyze. The free volumes in resorcinol were influenced both by high pressure and the gas coming into the crystallographic structure.
Źródło:: Nukleonika; 2013, 58, 1; 195-198
0029-5922
1508-5791
Pojawia się w:: Nukleonika
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 45.

Tytuł:: Principles of positron porosimetry
Autorzy:: Zaleski, R.
Powiązania:: https://bibliotekanauki.pl/articles/146520.pdf
Data publikacji:: 2015
Wydawca:: Instytut Chemii i Techniki Jądrowej
Tematy:: porous materials
positron annihilation lifetime spectroscopy (PALS)
positronium
extended Tao-Eldrup model
Opis:: The paper deals with positron porosimetry (PP), which is based on positron annihilation lifetime spectroscopy (PALS). The numerical analysis of positron lifetime spectra for PP is more demanding than in most of other applications of PALS. The resulting intensity distributions of ortho-positronium (o-Ps) lifetimes are interpreted in terms of the extended Tao-Eldrup (ETE) model, which provides the dependence between the o-Ps lifetime and pore size. Additionally, the relation between the intensity of an o-Ps component and the pore volume allows obtaining pore size distribution (PSD). The value of the empirical parameter Δ, which is dependent on material, can be estimated from the temperature dependence of an o-Ps lifetime. The most unique feature of PP among other techniques that allow determination of PSDs is its ability to perform measurements in almost any conditions. This makes this method suitable for various in situ studies. In this review article, both the capabilities and the limitations of PP are discussed. The methods to overcome some of the limitations are presented.
Źródło:: Nukleonika; 2015, 60, No. 4, part 1; 795-800
0029-5922
1508-5791
Pojawia się w:: Nukleonika
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 46.

Tytuł:: Lifetime Education in Aging Society
Autorzy:: Trafiałek, Elżbieta
Kozieł, Dorota
Powiązania:: https://bibliotekanauki.pl/articles/657673.pdf
Data publikacji:: 2011
Wydawca:: Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:: demographic old age
lifetime education
elderly people’s access to new technologies
Opis:: The text being presented, is devoted to analyzing determinants of the ef- ficiently functioning society - the society, which on the one hand, is characterized by unfavourable demographical changes, and on the other hand by promoting access to knowledge. The argument was based on the thesis that the agreement between demog- raphically aging society and information challenges of the European future is possible due to lifetime education and common access to knowledge and new technologies. It was observed that they are most efficient and appreciated forms of prophylactics in the fields of ageism and exclusion of the third generation. Social politicians are recommended to concentrate on this kind of prophylactics, however, since the process is long-lasting it should be treated as a priority, a determinant of the quality of life and future civilization.
Źródło:: Acta Universitatis Lodziensis. Folia Oeconomica; 2011, 250
0208-6018
2353-7663
Pojawia się w:: Acta Universitatis Lodziensis. Folia Oeconomica
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 47.

Tytuł:: A new approach to diagnostic symptom assessment based on information content measures
Nowa metoda oceny symptomów diagnostycznych oparta na miarach zawartości informacji
Autorzy:: Gałka, T.
Powiązania:: https://bibliotekanauki.pl/articles/327786.pdf
Data publikacji:: 2016
Wydawca:: Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:: lifetime consumption
diagnostic symptom
information content
wyczerpywanie żywotności
symptom diagnostyczny
zawartość informacji
Opis:: A complex diagnostic object typically generates a large number of diagnostic symptoms. For proper lifetime consumption monitoring it is necessary to select those which best represent technical condition deterioration. Such selection may be based on the Singular Value Decomposition method. The paper presents a novel alternative approach, which employs an information content measure. As the end of object life is approached, symptoms are to an increasing extent dominated by deterministic lifetime consumption processes and therefore become more predictable. Thus symptoms with the highest information content decrease rate should be considered most useful. For a proper assessment, however, symptom sensitivity to condition parameters should also be addressed. A new measure referred to as representativeness factor is proposed. Suitability of such approach is demonstrated for the fluid-flow system of a large steam turbine.
Złożone obiekty diagnozowania zwykle są źródłem wielu symptomów diagnostycznych. Dla właściwego monitorowania wyczerpywania żywotności należy wybrać te z nich, które najlepiej odwzorowują degradację stanu technicznego. Wybór ten można oprzeć na metodzie rozkładu względem wartości szczególnej. W pracy przedstawiono nowatorskie alternatywne podejście, w którym wykorzystuje się miarę zawartości informacji. Wraz ze zbliżaniem się do końca życia obiektu symptomy są w coraz większym stopniu określone przez deterministyczne procesy ubytku żywotności, a zatem stają się coraz bardziej przewidywalne. Za najbardziej użyteczne należy zatem uznać symptomy z najszybszym spadkiem zawartości informacji. We właściwej ocenie należy jednak uwzględnić także wrażliwość symptomu na parametry stanu. Zaproponowano nową miarę określoną jako współczynnik reprezentatywności. Przydatność takiego podejścia została zademonstrowana na przykładzie układu przepływowego turbiny parowej.
Źródło:: Diagnostyka; 2016, 17, 3; 103-108
1641-6414
2449-5220
Pojawia się w:: Diagnostyka
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 48.

Tytuł:: Przykład wykorzystania wskaźnika CLV w ocenie projektu inwestycyjnego
Example of Use of CLV Indicator to Assess Investment Project
Autorzy:: Miszczyński, Piotr
Powiązania:: https://bibliotekanauki.pl/articles/593328.pdf
Data publikacji:: 2015
Wydawca:: Uniwersytet Ekonomiczny w Katowicach
Tematy:: Customer Lifetime Value
Podejmowanie decyzji
Wycena inwestycji
Decision-making
Valuation of investments
Opis:: Od kilku lat można zaobserwować dynamiczne zmiany natury regulacyjnej i technologicznej, które mają duży wpływ na marże i zyskowność w sektorze bankowości detalicznej. Przy pojawiającej się presji rynkowej na konsolidację w polskim sektorze bankowym, coraz większe znaczenie ma prawidłowa ocena projektów inwestycyjnych w kontekście ich wyceny. Jedną z metod wspomagających wycenę projektu jest podejście szacowania długookresowej wartości klienta – CLV (Customer Lifetime Value). W pracy przytoczono różne podejścia do szacowania CLV oraz opisano przykład szacowania wskaźnika na gruncie polskim.
For several years, there have been observed some dynamic changes of the regulatory and technological nature, that have a large impact on margins and profitability in retail banking. With emerging market pressure for consolidation in the Polish banking sector, it is increasingly important to properly assess the investment project in the context of their valuation. One of the methods supporting the valuation of the project is the CLV (Customer Lifetime Value) approach. The paper presents different approaches to estimating CLV and describes an estimation of the indicator in the Polish market.
Źródło:: Studia Ekonomiczne; 2015, 248; 180-194
2083-8611
Pojawia się w:: Studia Ekonomiczne
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 49.

Tytuł:: Ortho-positronium migration in mesopores of MCM-41, MSF and SBA-3
Autorzy:: Zaleski, R.
Błażewicz, A.
Kierys, A.
Powiązania:: https://bibliotekanauki.pl/articles/147955.pdf
Data publikacji:: 2013
Wydawca:: Instytut Chemii i Techniki Jądrowej
Tematy:: nitrogen adsorption/desorption
porous materials
positron annihilation lifetime spectroscopy (PALS)
positronium migration
Opis:: Three materials: MCM-41, MSF and SBA-3 with a very similar pore diameter but different lengths of cylindrical pores were investigated using the nitrogen sorption method and positron annihilation lifetime spectroscopy. The size of primary pores and interparticle spaces obtained by both methods is similar. However, volume ratios between the discussed kinds of pores found by the above-mentioned methods differ significantly. Such discrepancy is the result of both ortho-positronium migration and the inaccessibility of the pores for nitrogen. Comparing the results of nitrogen sorption and positron annihilation lifetime spectroscopy allows us to estimate that connectivity between the primary pores and the interparticle spaces is the highest in MCM-41 and lowest in SBA-3.
Źródło:: Nukleonika; 2013, 58, 1; 235-240
0029-5922
1508-5791
Pojawia się w:: Nukleonika
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 50.

Tytuł:: Radiation Degradation of Bipolar Transistor Current Gain
Autorzy:: Miskiewicz, S.
Komarov, A.
Komarov, F.
Zayats, G.
Soroka, S.
Powiązania:: https://bibliotekanauki.pl/articles/1033766.pdf
Data publikacji:: 2017-08
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: radiation
numerical simulation
bipolar transistors
lifetime
minority charge carriers
recombination
current gain
Opis:: Spatial distribution of nonequilibrium minority charge carriers in bipolar transistors before and during the radiation exposure is described. Radiation-induced changes in the input and output characteristics and the current gain under the ⁶⁰Co 1.2 MeV γ -rays were calculated. It was shown that the collector current and current gain steadily fall due to irradiation in the considered range in the dose range 0-7×10⁵ rad. The simulation results correlate well with the experimental data obtained at the Research and Production Corporation "Integral".
Źródło:: Acta Physica Polonica A; 2017, 132, 2; 288-290
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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