Методы суперкомпьютерного моделирования. Часть 2. В серии "Механика, управление и информатика"
This issue is the collection of the papers based on the talks presented at the extended workshop “Methods of simulations on supercomputers”, which was held at 21–3 April 2014, in Tarusa hotel Interkosmos of the RAS Space Research Institute. It is the workshop in the series of extended workshops, devoted to the computer technologies in natural sciences. Eighth workshop, as a current one, named “Methods of simulations on supercomputers”. The name is connected with the fact that workshops are supported within the research program the grant by Russian Scientific Foundation 14-21-00158 «Algorithms and methods for mathematical simulations on supercomputing systems, including hybrid ones». Important highlight of the workshop is the active participation of the young scientists, and more than half of the talks were done by the young speakers.
The work is devoted to building trusted information systems with 3-tier architecture, which
satisfy high requirements of information security, reviewed main information security
vulnerabilities and information system threatening, offered algorithms for constructing that
systems, grounded selection of 3-tier architecture to construct trusted system. Those algorithms
allow to operate with rate category information.
This volume collects the referred papers based on plenary, invited, and oral talks, as well on the posters presented at the Third International Conference on Computer Simulations in Physics and beyond (CSP2018), which took place September 24-27, 2018 in Moscow. The Conference continues the tradition started by an inaugural conference in 2015. It took place on the campus of A.N. Tikhonov Moscow Institute of Electronics and Mathematics in Strogino, was jointly organized by the National Research University Higher School of Economics, the Landau Institute for Theoretical Physics and Science Center in Chernogolovka.
The Conference is a multidisciplinary meeting, with a focus on computational physics and related subjects. Indeed, methods of computational physics prove useful in a broad spectrum of research in multiple branches of natural sciences, and this volume provides a sample.
We hope that this volume will interest readers, and we are already looking forward to the next conference in the series.
CSP2018 Conference Chair and Volume Editor
In this volume we have collected papers based on the presentations given at the International Conference on Computer Simulations in Physics and beyond (CSP2015), held in Moscow, September 6-10, 2015. We hope that this volume will be helpful and scientifically interesting for readers.
The Conference was organized for the first time with the common efforts of the Moscow Institute for Electronics and Mathematics (MIEM) of the National Research University Higher School of Economics, the Landau Institute for Theoretical Physics, and the Science Center in Chernogolovka. The name of the Conference emphasizes the multidisciplinary nature of computational physics. Its methods are applied to the broad range of current research in science and society. The choice of venue was motivated by the multidisciplinary character of the MIEM. It is a former independent university, which has recently become the part of the National Research University Higher School of Economics.
Computer simulation, an active learning technique, is now one of the advanced pedagogical technologies. The use of simulation games in the educational process allows students to gain a firsthand understanding of the processes of real life. Public administration, public policy, and political science courses increasingly adopt simulation games in universities worldwide. Besides person-to-person simulation games, there are computer-based simulations in public administration education. Currently in Russia the use of computer-based simulation games in Master of Public Administration (MPA) curricula is quite limited. This paper focuses on computer-based simulation games for students of MPA programs. Our aim was to analyze outcomes of implementing such games in MPA curricula. We have done so by (1) developing three computer- based simulation games about allocating public finances, (2) testing the games in the learning process, and (3) conducting a posttest examination to evaluate the effect of simulation games on students’ knowledge of municipal finances. This study was conducted in the National Research University Higher School of Economics (HSE) and in the Russian Presidential Academy of National Economy and Public Administration (RANEPA) during the period September to December 2015, in Saint Petersburg, Russia. Two groups of students were randomly selected in each university and then randomly allocated either to the experimental or the control group. In control groups (n=12 in HSE, n=13 in RANEPA) students had traditional lectures. In experimental groups (n=12 in HSE, n=13 in RANEPA) students played three simulation games apart from traditional lectures. This exploratory research shows that the use of computer-based simulation games in MPA curricula can improve students’ outcomes by 38%. In general, the experimental groups had better performance on the posttest examination (figure 2). Students in the HSE experimental group had 27.5% better scores than students in the HSE control group. Students of the RANEPA experimental group had 38.0% better scores than students in the RANEPA control group. Research indicates that lecture-based courses are less effective than courses with more interactive approaches. Therefore, our study highlights the need to implement computer-based simulation games in MPA programs in Russian universities. Computer-based simulation games provide students with practical skills for their future careers.
Computer simulation of mechanical testing is used primarily for the correct interpretation of their results and is particularly relevant in cases, when the properties of the material during deformation are essentially nonlinear. For example: when we study mechanical properties of materials with high rate sensitivity. First of all it is superplastic titanium alloys. Superplastic materials exhibit the ability to severe plastic deformation without discontinuities if forming occurs in a narrow range of strain rates, specific to each alloy and temperature-dependent. In the study of superplastic materials, it’s necessary to maintain a constant rate of deformation of the sample. This is achieved by conducting an experiment with a special program loading, crosshead speed at which change during the experiment.
The article discusses the utility of automated revenue management systems, designed for the needs of civil aviation. The analysis of revenue management systems in Russian airlines and Russian carrier position in the international air transportation market are provided. The need to use the automated revenue management system to increase profits of the operator is identified. A strategy of selling tickets, taking into account overbooking as revenue management strategy, allowing both to increase employment of passenger seats and reduce the loss of the carrier from possible no-show passengers to register, is considered. Creation of the simulator to assess the effectiveness of the commercial activities of the airline is proposed.
Computer simulations of electrostatic discharges (ESD) effect on high-power MOSFET-transistors with built-in protection have been carried out. It was found that the transistors with low gate-source capacitance are more sensitive to the ESD effect.The dependence between printed circuit board (PCB) capacity, causing breakdown of MOSFET-transistor gate dielectric, and ESD voltage was established. It is shown that for transistor haying low gate-source capacitance, the existence of the built-in protection does not prevent gate dielectric breakdown at electrostatic discharges. It is recommended to provide external ESD protection for high-power MOSFET-transistors with built-in protection having low gate-source capacitance, for example, having turned on the ESD protection diode in the electric circuit.
Rigorous nonlinear analysis of the physical model of Costas loop is very difficult task, so for analysis, simplified mathematical models and numerical simulation are widely used. In the work it is shown that the use of simplified mathematical models, and the application of non rigorous methods of analysis may lead to wrong conclusions concerning the operability of Costas loop.
A model for organizing cargo transportation between two node stations connected by a railway line which contains a certain number of intermediate stations is considered. The movement of cargo is in one direction. Such a situation may occur, for example, if one of the node stations is located in a region which produce raw material for manufacturing industry located in another region, and there is another node station. The organization of freight traﬃc is performed by means of a number of technologies. These technologies determine the rules for taking on cargo at the initial node station, the rules of interaction between neighboring stations, as well as the rule of distribution of cargo to the ﬁnal node stations. The process of cargo transportation is followed by the set rule of control. For such a model, one must determine possible modes of cargo transportation and describe their properties. This model is described by a ﬁnite-dimensional system of diﬀerential equations with nonlocal linear restrictions. The class of the solution satisfying nonlocal linear restrictions is extremely narrow. It results in the need for the “correct” extension of solutions of a system of diﬀerential equations to a class of quasi-solutions having the distinctive feature of gaps in a countable number of points. It was possible numerically using the Runge–Kutta method of the fourth order to build these quasi-solutions and determine their rate of growth. Let us note that in the technical plan the main complexity consisted in obtaining quasi-solutions satisfying the nonlocal linear restrictions. Furthermore, we investigated the dependence of quasi-solutions and, in particular, sizes of gaps (jumps) of solutions on a number of parameters of the model characterizing a rule of control, technologies for transportation of cargo and intensity of giving of cargo on a node station.
Event logs collected by modern information and technical systems usually contain enough data for automated process models discovery. A variety of algorithms was developed for process models discovery, conformance checking, log to model alignment, comparison of process models, etc., nevertheless a quick analysis of ad-hoc selected parts of a journal still have not get a full-fledged implementation. This paper describes an ROLAP-based method of multidimensional event logs storage for process mining. The result of the analysis of the journal is visualized as directed graph representing the union of all possible event sequences, ranked by their occurrence probability. Our implementation allows the analyst to discover process models for sublogs defined by ad-hoc selection of criteria and value of occurrence probability
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
The Handbook of CO₂ in Power Systems' objective is to include the state-of-the-art developments that occurred in power systems taking CO₂ emission into account. The book includes power systems operation modeling with CO₂ emissions considerations, CO₂ market mechanism modeling, CO₂ regulation policy modeling, carbon price forecasting, and carbon capture modeling. For each of the subjects, at least one article authored by a world specialist on the specific domain is included.