Software & Systems

Articles of journal № 2 at 2014 year.

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31. Simulation of taxonomy program of parts production technology for mechanical-engineering using petri nets [№2 за 2014 год]
Author: Shestakov A.M.
Visitors: 11910
The article considers a model created using Petri nets. It allows analyzing the tran smission and receipt of data from computers to the technology taxonomy program for details production on the Internet. The purpose of modeling is simulation of the program failure, deadlocks search (no loops and dead ends), and identifying bottlenecks when transmiting data. In the simulation experiments failures of computer service by the taxonomy program are simulated as appearance of a random number of markers chips in the position. When there are no failures the program works automatically. The position serves the teams on the computer taxonomy. When there is an access denial in the program, the arc closes the transition and returns to the starting position. In normal operating mode at any time the Petri nets programs provide simultaneous conflict -free reference of multiple computers to taxonomy program with parallel work. Parallelism means that any of the computers that receive the access to the program can start referring or finish it before or after the other. The Petri nets apparatus c an be used as a formal language to describe the Web application model of taxonomy of the details production technologies. The Pe-tri nets are an extension of the classical graph theory. The Petri nets theory of enables the system specification using math e-matical representation. Its analysis helps to get important information about the structure and dynamic behavior of the mo d-eled system. Based on Petri nets the spanning tree of the reachability graph is constructed. Its points are all possible reac hable network marks. The analysis of the spanning tree highlightes its properties such as: security (number of marks in any position does not exceed 1); persistence (the inability of appearing and deleting resources in the simulated object) and vividness (no loops and dead ends.) The developed Petri net does not have loops and dead ends. Its taxonomy program can be used in production.

32. Implementation of the parameter optimization algorithm for molecular dynamic force field REAXFF [№2 за 2014 год]
Authors: Shefov K.S., Stepanova M.M.
Visitors: 9713
Molecular dynamic methods that use ReaxFF (Reactive Force Field) allow obtaining sufficiently good results in simulating large multicomponent chemically reactive systems. ReaxFF is implemented in the standard software package LAMMPS. However, pre-optimization of numerous parameters of this force field for a specific system is required for correct computations. This paper presents a parallel program that implements one-parameter search algorithm for the molecular dy-namic force field ReaxFF. The program uses data obtained by accurate quantum chemical computations of characteristics (training set) of chemical compounds simple models for t he optimization process. The parameter search is based on the min-imization of the error function. This is a sum of squared deviations of training set entries computed by ReaxFF from ones computed by quantum chemical methods. The paper describes the parameter search algorithm and shows the program block-scheme. Molecular dynamic simulator LAMMPS is used to search the minimum of ReaxFF potential energy (optimal geom e-try) of the training set models. The package LAMMPS is compiled as a library and linked to the program. The program al-lows searching ReaxFF parameters for arbitrary types of chemically reactive systems. It is necessary for specific numerical simulations of chemical reactions using the molecular dynamic package LAMMPS on high -performance parallel computers.

33. Integrated system for development of polymer composite material products based on plm methodology [№2 за 2014 год]
Authors: Yablochnikov E.I., Vosorkin A.S., Tsupikov A.V.
Visitors: 12524
The article considers topical issues of business-process automation for polymer composite materials products design. It observes the necessity to create an integrated information environment for different profile specialists team -work: designers, production engineers, materials engineers. The authors offer a block diagram of the integrated system that repr e-sents the functions of data support for specialists and control of the design process and project data. The approach to build ing the system is based on the PLM methodology (data support and product lifecycle management). The ke y point is using virtual simulation systems and computer-aided engineering systems (CAE-systems) of different classes (simulation of new materi-als, technologies, product designs). The article provides the main properties characteristics of the integrated system. They include data support and object-oriented database model, user interface, external systems integration, configure and scale ability, secure data access, proc e-dures that increase the automation level. The paper describes a new business -process of solving tasks under consideration. Its effectiveness is determined by the possibility of collective analysis and intermediate result approval, smaller iteration deg ree, using special-purpose computer modeling systems. The integrated system development is connected with knowledge base development. And the knowledge base contains the rules for the materials selection and design -technology constructions of products.

34. The integrated system for structured physical knowledge processing [№2 за 2014 год]
Authors: Yarovenko V.A., Fomenkov S.A.
Visitors: 10002
The article describes the automated engineering processes for specialists of technical solutions synthesis and research specialists. It is based on the research area of "CAD and PC" department scienti fic school of Volgograd State Technical University. The paper describes the model of the multi -agent system for structured physical knowledge processing and “Sophie II” automated system. “Sophie II” is implemented in this model. The research led to creatin g partly formalized mod-els of a multi-agent system and an agent. To implement the interaction between the agents we use the auctions principle. It a l-lows changing the composition of agents. To do this, we used the contract chains model. It implements this principle. While implementing a multi-agent system we used FIPA standard. It regulates the overall system architecture, the agents states and the principles of interaction between agents. All the described models are implemented in the “Sophie II” automate d system. This system allows combining the search techniques of physical effects, the synthesis of the physical principles of action, t he filling the physical effects fund from original sources and the administration of the physical effects database. A uni fied phy s-ical effects database was created. A number of tests was performed to assess the efficiency and effectiveness of the "Sophie II". The system has successfully passed the tests.

35. The system for multi-criteria decision analysis decernsmcda and its practical application [№2 за 2014 год]
Authors: Yatsalo B.I., Gritsyuk S.V., Didenko V.I., Mirzeabasov O.A.
Visitors: 17036
Land-use planning, environmental protection, and risk management require the use of up -to-date decision sup-port systems. Such systems are based on effective implementation of geographic information systems (GIS) to analyse and represent spatial data as well as on multicriteria decision analysis (MCDA) methods and tools. The paper describes DecernsMCDA decision support system. It includes different well-known and several original methods to analyse discrete multicriteria problems. The authors present a survey of MCDA software. There is a description of the DecernsMCDA struc-ture. Its difference from existing systems is pointed out. A brief description of multicriteria m odels included in DecernsMCDA is presented. It includes the methods for uncertainty analysis based on probabilistic approaches and fuzzy sets. The paper presents the references to the examples of DecernsMCDA practical application for solving multicriteria prob-lems related to land-use planning and risk management.

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