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Wyszukujesz frazę "Kuznetsov, V." wg kryterium: Autor


Tytuł:
Current conveyor equation-defined macromodels for wideband RF circuit design
Autorzy:
Brinson, M.
Kuznetsov, V.
Powiązania:
https://bibliotekanauki.pl/articles/397845.pdf
Data publikacji:
2017
Wydawca:
Politechnika Łódzka. Wydział Mikroelektroniki i Informatyki
Tematy:
Qucs
current conveyors
compact semiconductor device modelling
equation-defined devices
macromodels
Verilog-A module synthesis
konwejer prądowy
modelowanie urządzeń półprzewodnikowych
makromodele
Opis:
A high percentage of analogue integrated circuit designs use voltage domain signal processing techniques. Given the fact that integrated circuit current conveyors are high bandwidth current processing devices, often with superior RF performance compared to comparable voltage domain devices, it is surprising that the number of current mode integrated circuits available, as standard of-the-shelf industrial items, is so small. This paper introduces equation-defined device and Verilog-A synthesis approaches to the macromodelling of current conveyor integrated circuits. To illustrate the proposed modelling techniques the properties of a number of modular behavioural level current conveyor macromodel cells are described and their performance compared. The material presented is intended for analogue device modellers and circuit designers who wish to simulate large signal current domain integrated circuit designs. It also demonstrates how synthesized Verilog-A modules can be derived from equation-defined device and conventional subcircuits to form functional, computationally efficient current conveyor macromodels. To illustrate the application of behavioural current conveyor macromodels the design of a six cell CCII+ instrumentation amplifier is introduced and its performance discussed.
Źródło:
International Journal of Microelectronics and Computer Science; 2017, 8, 2; 65-71
2080-8755
2353-9607
Pojawia się w:
International Journal of Microelectronics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Qucs equation-defined and Verilog-A higher order behavioral device models for harmonic balance circuit simulation
Autorzy:
Brinson, M.
Kuznetsov, V.
Powiązania:
https://bibliotekanauki.pl/articles/397905.pdf
Data publikacji:
2015
Wydawca:
Politechnika Łódzka. Wydział Mikroelektroniki i Informatyki
Tematy:
Qucs
Xyce
Harmonic Balance RF simulation
compact semiconductor device modelling
equation-defined devices
macromodel
modelowanie urządzeń elektronicznych
makromodele
Opis:
This paper is concerned with the development and evaluation of a number of modeling techniques which improve Qucs Harmonic Balance simulation performance of RF compact device models. Although Qucs supports conventional SPICE semiconductor device models, whose static current/voltage and dynamic charge characteristics exhibit second and higher order derivatives may not be continuous, there is no guarantee that these will function without Harmonic Balance simulation convergence problems. The same comment also applies to a number of legacy compact semiconductor device models. The modeling of semiconductor devices centered on non-linear Equation-Defined Devices and blocks of Verilog-A code, combined with linear components, is introduced. These form a class of compact macromodel that has improved Harmonic Balance simulation performance. To illustrate the presented modeling techniques RF diode, BJT and MESFET macromodels are described and their Harmonic Balance performance simulated with Qucs and Xyce©.
Źródło:
International Journal of Microelectronics and Computer Science; 2015, 6, 2; 49-58
2080-8755
2353-9607
Pojawia się w:
International Journal of Microelectronics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Recent developments in Qucs-s Equation-Defined modelling of semiconductor devices and IC’s
Autorzy:
Brinson, M.
Kuznetsov, V.
Powiązania:
https://bibliotekanauki.pl/articles/397783.pdf
Data publikacji:
2017
Wydawca:
Politechnika Łódzka. Wydział Mikroelektroniki i Informatyki
Tematy:
Qucs
Qucs-S
Ngspice
XSPICE Code Models
compact semiconductor device modelling
Equation-Defined Devices
EDD
macromodels
XSPICE Code Model
makromodele
Opis:
The Qucs Equation-Defined Device was introduce roughly ten years ago as a versatile behavioural simulation component for modelling the non-linear static and dynamic properties of passive components, semiconductor devices and IC macromodels. Today, this component has become an established element for building experimental device simulation models. It’s inherent interactive properties make it ideal for device and circuit modelling via Qucs schematics. Moreover, Equation-Defined Devices often promote a clearer understanding of the factors involved in the construction of complex compact semiconductor simulation models. This paper is concerned with recent advances in Qucs-S/Ngspice/XSPICE modelling capabilities that improve model construction and simulation run time performance of Equation-Defined Devices using XSPICE model syntheses. To illustrate the new Qucs-S modelling techniques an XSPICE version of the EPFL EKV v2.6 long channel transistor model together with other illustrative examples are described and their performance simulated with Qucs-S and Ngspice.
Źródło:
International Journal of Microelectronics and Computer Science; 2017, 8, 1; 29-35
2080-8755
2353-9607
Pojawia się w:
International Journal of Microelectronics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The method for increasing the efficiency of equipment’s maintenance in railway traction power supply systems
Autorzy:
Matusevych, O.
Kuznetsov, V.
Sychenko, V.
Powiązania:
https://bibliotekanauki.pl/articles/223664.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
railway traction
power systems
efficiency
maintenance equipments
traction substation
trakcja kolejowa
systemy zasilania
wydajność
konserwacja urządzeń
Opis:
Purpose. To develop the method for increasing the efficiency of the equipment’s maintenance and repair system, ensuring necessary level of operational reliability of the equipment, safety and reliability of the electric equipment with minimal expenses on operation. Relevance. Aging of the power equipment in railway power supply systems sharply raised a need for assessment of its states and degree of risk for operation outside rated service life. In critical conditions of technological processes and operational modes of the railways it is necessary to increase the equipment’s operational reliability. The scheduled maintenance and repair system whose main technical and economic criterion is the minimum of equipment’s downtimes on the basis of a rigid regulation of repair cycles, in the conditions of market regulations in the field of repair in many cases does not provide the optimal decisions due to insufficient financing. The solution of this problem is possible by improvement of the maintenance and repair system. Under these conditions the main direction for supporting the operational reliability of power electric equipment on TS is a development of the modern methods based on individual supervision over real changes of technical condition of power equipment. Scientific novelty. In this article the authors proposed an integrated approach, on the basis of which can be developed the effective maintenance and repair system for traction power supply systems. Proposed approach allowed to react quickly to changes of service conditions on traction substations, to control the technical condition of power electric equipment under the conditions of uncertainty, to establish interrelation between quality of service and operational reliability of the equipment, to choose a service strategy on traction substations. Practical importance. The validity of the developed method was confirmed by the results of calculations and practically by choosing the optimal maintenance's option for transformer TDTN-25000/150-70 U1 (ТДТН-25000/150-70 У1) on traction power supply substation.
Źródło:
Archives of Transport; 2018, 47, 3; 39-47
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessing the Environmental Condition of Minor Rivers in Urban Areas
Autorzy:
Kuznetsov, V. S.
Petrov, D.S.
Powiązania:
https://bibliotekanauki.pl/articles/124132.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
sediment pollution
minor rivers
oil product pollution
environmental monitoring
heavy metal pollution
Opis:
This article is devoted to the study of water and sediment pollution in the channel of the Neva delta. Spectrophotometry was used to determine the concentration of pollutants in water. In the chemical analysis of the precipitate, atomic absorption spectroscopy and infrared spectroscopy were used. Analysis of the hydrochemical composition and sediment of the Smolenka River showed high concentrations of heavy metals and petroleum products. At the same time, the hydrochemical composition of the Smolenka River is highly unstable, but the concentration of oil products and lead in the sediments indicates the presence of local pollution sources. Based on our findings, we are guided by the restoration of the aquatic environment.
Źródło:
Journal of Ecological Engineering; 2017, 18, 6; 110-114
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Assessment of Alumina Production Waste Impact on Natural Water
Autorzy:
Kuznetsov, V. S.
Suprun, I. K.
Powiązania:
https://bibliotekanauki.pl/articles/123535.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
alumina
red mud
utilisation
sludge dump
Opis:
The paper is dedicated to the issue of assessment of alumina (red mud) production waste on natural water. The growth of the number of aluminium-producing facilities leads to the expansion of exclusion areas to store the production waste – sludge dumps. A considerable part of research on red mud utilisation is focused on its use in the iron-and-steel industry. Furthermore, the technologies of red mud usage in the construction industry gain substantial significance for land reclamation, isolation of polluted industrial and agricultural lands as well as the effluent and industrial emissions treatment.
Źródło:
Journal of Ecological Engineering; 2018, 19, 2; 154-158
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reduction of an Adverse Impact During Well Drilling by Means of Drilling Waste Usage
Autorzy:
Kuznetsov, V. S.
Suprun, I. K.
Powiązania:
https://bibliotekanauki.pl/articles/125400.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
bore mud
utilisation
toxicity
well site
sludge pit
dehumidification
oil production
refining
expression
waste treatment
Opis:
The problem of drilling waste utilisation is assumed to be resolved through the implementation of the complex of environment protection measures in production engineering. They include primarily the use in the process of well drilling of drilling mud on the basis of water-soluble biodegradable polymers and a four-stage drilling mud refining system. Secondly, the usage of the well site construction with trenching for allocation of expressed bore mud and a temporary ground tank for drilling waste water.
Źródło:
Journal of Ecological Engineering; 2017, 18, 2; 12-15
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distribution of Excess Regenerative Energy in Electric Transport Systems on the Basis of Fuzzy Logic Application
Autorzy:
Sablin, O.
Kuznetsov, V.
Shinkarenko, V.
Ivanov, A.
Powiązania:
https://bibliotekanauki.pl/articles/223524.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
electric transport
regeneration of the electric power
stores
inverters
regulation of voltage
traction
external power supply
fuzzy logic
transport elektryczny
regeneracja energii elektrycznej
magazyny
falowniki
regulacja napięcia
trakcja
zasilanie zewnętrzne
logika rozmyta
Opis:
Purpose. To develop the fuzzy model of distribution of excess regenerative energy in traction and external power supply systems allowing to exercise effective operation of the power equipment. Relevance. For effective distribution of excess regenerative energy in systems of electric transport, as well as for systems equipped with stationary stores of energy and inverting traction substations with regulators of output voltage it is necessary to solve a number of the problems with high degree of uncertainty demanding taking into account a set of random factors such as the modes of power lines and traction loadings. These factors have to be considered in operation for choosing the rational modes of energy stores, inverters and regulators of voltage on buses of substations to provide the rational conditions for energy regeneration on electric transport. Scientific novelty. The control system of energy storage devices, inverters and traction substation output voltage regulators, designed on the basis of fuzzy logic, can provide the necessary conditions for the regeneration on electric transport on sections with a shortage of traction power consumption and allows to optimize the distribution of excess braking energy of transport vehicles. It is achieved by determining the rational relationship between the components of the excess current of regeneration in real time, which can ensure a minimum of power losses of regenerative energy in traction and external power supply systems. Practical importance. The use of the developed approach is effective under the conditions of incomplete information received by measurement systems and on the basis of additional studies it can allow to minimize rated capacity of stores, inverters and traction substation output voltage regulators that could reduce the costs of modernization of existing sections and electrification of new electric transport systems.
Źródło:
Archives of Transport; 2017, 42, 2; 53-63
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improvement of the regenerating energy accounting system on the direct current railways
Autorzy:
Kuznetsov, V. G.
Sablin, O. I.
Chornaya, A. V.
Powiązania:
https://bibliotekanauki.pl/articles/224043.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
energy accounting system
power consumption
power supply
traffic size
regeneration
system rozliczeniowy energii
pobór mocy
zasilanie
wielkość ruchu
regeneracja
Opis:
Purpose. Monitoring of current state of quantitative indices of regenerative energy in the suburban movement, the analysis of the factors influencing its volumes and improvement the principles of the train regenerative energy accounting on the basis of it. Relevance. Development of effective measures of increase the regeneration efficiency of the electric power in system of electric traction demands comprehensive completeness of information on quantitative indices of regeneration energy volumes at all possible levels of its analysis, in particular on the corresponding sections of RS movement that will allow to establish the influence on the level of regeneration of various factors, such as parameters of traction power supply and the organization of train service. As the existing system of the regenerative energy accounting does not allow to consider the specified factors, development of the principles for increasing the efficiency of the analysis of volumes of return energy to a contact line during regenerative braking on DC rolling stock is the actual direction of researches. Collective monitoring of regeneration energy volumes by specialists of locomotive service, power supply and traffic operating departments will be essentially new approach to definition of real factors and taking effective decisions for increasing of using of regenerative energy. Scientific novelty. It’s offered to consider the influence on quantitative indices of regenerative energy the parameters of traction power supply and the organization (sizes) of traffic service on sections. Practical importance. Increasing the efficiency of the regeneration energy accounting is an important element in drawing up the balance of energy for electric traction system, development of the effective methods for improvement of the conditions of regeneration in it and in estimation of its power indicators in general.
Źródło:
Archives of Transport; 2015, 36, 4; 35-42
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of anti-ricochet properties of body armor with steel armor panels
Autorzy:
Egorov, A.I.
Kuznetsov, V.M.
Logatkin, S.M.
Khromushin, V.A.
Powiązania:
https://bibliotekanauki.pl/articles/237959.pdf
Data publikacji:
2009
Wydawca:
Instytut Technologii Bezpieczeństwa Moratex
Tematy:
kamizelka kuloodporna
pancerz ze stali
odporność balistyczna
bullet-proof vest
stainless steel armor
ballistic resistance
Opis:
The paper describes the ballistic experiment on counter-ricochet structures of armor vests with steel panels of protection levels 2, 3 and 5. A method of experimental evaluation of ballistic characteristics of such counter-ricochet structures was developed with substantiation of the target conditions. As a result of experimental ballistic and medical/biological research the parameters of witness plates were determined and justified. In the experimental research ballistic resistance of commercially-available vest counter-ricochet structures was investigated by methods of energy consumption and V50 evaluation. Special technical requirements were worked-out for counter-ricochet structures of bulletproof vests with steel panels.
Źródło:
Techniczne Wyroby Włókiennicze; 2009, R. 17, nr 2/3, 2/3; 63-66
1230-7491
Pojawia się w:
Techniczne Wyroby Włókiennicze
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Resource-saving technologies of railway transportation of grain freights for export
Autorzy:
Kozachenko, D.
Vernigora, R.
Kuznetsov, V.
Lahvinova, N.
Rustamov, R.
Papahov, A.
Powiązania:
https://bibliotekanauki.pl/articles/223476.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
rail transportation
grain export
efficiency
consignor routing
concentration of loading
cluster analysis
transport kolejowy
eksport zboża
wydajność
Opis:
The research objective is to increase the efficiency of export railway transportation of grain freights in Ukraine by the introduction of consignor routing, a concentration of loading of grain on junction elevators and the organization of the movement of grain routes according to the schedule. According to the researchers in USA and EU, one of the effective directions for decreasing the expenses in a logistic chain of grain delivery to ports is consignor routing of railway transportation. Consignor routing of transportations of grain freights provides a concentration of their loading at junctions. The choice of junctions is proposed to be carried out on the basis of methods of the cluster analysis. For formation of regions for a concentration of grain loading the theory of sets and multicriteria optimization are used. As a result, on the basis of the modified simplex method are chosen 24 regions of possible concentration of grain loading that cover 70 stations on Ukrainian railways providing 7,5 million t consignor routing for grain in a year with minimal additional expenses. The assessment of the efficiency of railway transportation routing of grain freights is calculated with use of the developed simulation model. Researches showed that application of consignor routing allows to reduce a turn-round cycle for grain wagon in a logistic chain of deliveries up to 27%, and application of the schedule for consignor routes allows to reduce a turn-round cycle up to 62%, in comparison with transportation by car loading. Thus, as showed the calculations executed for one of the directions of grain transportation for export, the necessary operation park of grain-carrier wagons is reduced twice, thereby allowing to cut logistic expenses on a delivery of the Ukrainian grain through seaports to the world markets.
Źródło:
Archives of Transport; 2018, 45, 1; 63-74
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optically Active Si:Er Layers Grown by the Sublimation MBE Method
Autorzy:
Stepikhova, M.
Andreev, A.
Andreev, B.
Krasil'nik, Z.
Shmagin, V.
Kuznetsov, V.
Rubtsova, R.
Jantsch, W.
Ellmer, H.
Palmetshofer, L.
Preier, H.
Karpov, Yu.
Piplits, K.
Hutter, H.
Powiązania:
https://bibliotekanauki.pl/articles/1992203.pdf
Data publikacji:
1998-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.15.Hi
Opis:
We report the first application of sublimation molecular beam epitaxy to grow uniformly and selectively doped Si:Er layers with Er concentration up to 5×10$\text{}^{18}$ cm$\text{}^{-3}$. The Hall concentration of electrons is about 10% of total Er contents. The mobility is 300-400 cm$\text{}^{2}$ V$\text{}^{-1}$ s$\text{}^{-1}$ at 300 K. All samples exhibit photoluminescence at 1.537 μm up to 100-140 K.
Źródło:
Acta Physica Polonica A; 1998, 94, 3; 549-554
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation for Service Quality and Berths Occupancy Assessment
Autorzy:
Kuznetsov, A.L.
Kirichenko, A.V.
Powiązania:
https://bibliotekanauki.pl/articles/117027.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
port operations
berths occupancy assessment
service quality
ship maneuvering
ship handling
simulation technique
berthing
object-oriented simulation
Opis:
Current development of the maritime transportation system, namely fleet and ports specialization, growth of vessel sizes, rationalization of routs, trade regionalization etc., has made many traditional approaches and calculation techniques practiced for many long years in port design procedures to be inadequate and insufficient. A generally acknowledged tool for this task today is the simulation technique. In the same time, modern object oriented simulation approach provides usually only ad hoc solution for a project. It lacks the generality that was the main and natural feature of its traditional analytical predecessors. Very high time and labor consumption of simulation comes to a conflict with a very narrow scope of the resulting model’s application domain. This paper describes a new approach used to create a simulation tool for the port designers and planners combining the universality and generality of the analytical (so called “static”) methods with the efficiency and accuracy of the object-oriented simulation. The concept represented in the paper was implemented in the software product, which enabled to conduct experiments that proved the validity and adequacy of the model. The simulation tool was used in several sea port design project and now is a common instrument of several leading port design and consulting company in Russian Federation.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2016, 10, 3; 489-492
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Methodological Problems of Modern Transportation Logistics
Autorzy:
Kuznetsov, A. L.
Kirichenko, A. V.
Powiązania:
https://bibliotekanauki.pl/articles/117606.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
modern transportation logistics
logistics
methodological problems
modern logistics
transportation logistics
sea transportation
global supply chain
logistic supply chain
Opis:
The terminology and conceptual apparatus of modern logistics as a scientific discipline is far from being shaped. Researches and developers of legislative and norm-setting documents are obliged to use their own or barrowed terminology, in both case not shared ubiquitously. Consequently, the interpretations even of basic concepts differ significantly. In particular, there exists an academic and practical point of view that refuse the right for existence of the term “transportation logistics”. This clause is explained by the proclaimed omnipresence and universality of logistics, which has in its operational glossary the term “transportation”, treated as a local, subordinated and thus secondary function. This paper tries to set a decisive rule to distinguish between general logistics and transportation logistics, arguing that these two disciplines are well separated by the objects and methodology, knowledge and activities. In transportation logistics defined this way the authors examine two principal components of the transportation processes, storage (warehousing) and movement (shipping). This consideration lead to conclusions that the classical mathematical toolkit is not fitted for the design and management of modern global supply chains.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2018, 12, 3; 611-616
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of an Engineer Operation Aimed at the Reduction of Atmospheric Dust Pollution in the Decommissioning of Iron-Ore Treatment Waste
Autorzy:
Suprun, Igor
Kuznetsov, Vladimir S.
Ivanov, Andrey V.
Powiązania:
https://bibliotekanauki.pl/articles/123979.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
reduction
dust pollution
decommissioning
iron-ore waste
Opis:
This work covers the pollution of the atmosphere during the work of the Mikhailovsky Mining and Refining Facility which is located within 100 km from the city of Kursk, in the city of Zheleznogorsk. Over the past few years in the whole world, the anthropogenic activity, connected mainly with the locations of mineral production and those of mineral treatment and processing, has become increasingly dangerous for the natural environment. Resource development in open pits causes the formation of inorganic dust. The dust is released into the atmosphere at all stages of the enterprise’s technical process. The principal sources generating inorganic dust during open mining of iron deposits include: blasting operations in an open pit, the work of transfer points, the enrichment process at a factory, pellet firing as well as dusting from the surfaces of stock dumps and dry tailings beaches.
Źródło:
Journal of Ecological Engineering; 2019, 20, 4; 23-28
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł

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