Software & Systems

Articles of journal № 3 at 2012 year.

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1. Templet – method of process oriented simulation of parallelism [№3 за 2012 год]
Author: Востокин С.В.
Visitors: 13651
This paper presents a new methodology of simulation of parallel processes TEMPLET being developed by the author at the department of information systems and technologies of Samara State Aerospace University. It reviews the improved version of notation, which makes it possible: to describe interprocess communication protocols in the form of sequence of communicated messages; to represent the logic of process operation by means of message processing procedures; to visualize the processes and their communication by means of annotated graphs. Simulation method is designed to describe the systems with inherent parallelism on the basis of a process approach. The following aspects of methodology are focused on: the way of process decomposition into message processing procedures; description of process communication protocols in the form of finite-state machines; graphic notation for visualization of process model; detailed description of rules for transmission of model dynamics. An example of the simplest system of fork-join type processes is given to illustrate this. The article consists of five parts. The Introduction considers the purposes of design. The main part shows the upper level diagram describing the process composition and pictographic elements used in it. Then the analysis of examples for the objects comprising the process composition diagram is represented. Further the communication object diagrams are reviewed – channels, diagrams of message processing objects - processes. The representation finishes with a brief description of the support software for TEMPLET simulation methodology and a reference to sources with examples of its usage. Besides, the reference to the web site of the research project related to this methodology is proposed, where you can find its support software.

2. Automation of management of national research university and monitoring of its activity [№3 за 2012 год]
Authors: Еленев Д.В., Кузьмичев В.С., Пашков Д.Е.
Visitors: 12745
The problem to be solved is to build an integrated automated information system of university management and information analytical system of monitoring of subdivision activities and quantitative assessment of university output quality. The purpose of the first one is automation of the university management system on the basis of creation of the unified integrated database, and its development is carried out by means of introduction and organization of cooperative work of specialized software products to implement various business functions. Introduction of the integrated automated information system of university management made it possible to improve considerably the management accounting at the university, to bring a set of business processes into the legal framework, to carry out more emphasized formation of executors’ liability points, to regulate the internal structure and minimize the amount of output document, considerably reduce the terms of structural analysis of the university performance indicators and work with external organizations. The system of monitoring of subdivision activity and quantitative assessment of quality of university output is aimed at increase of management system efficiency and quality of work of university subdivisions, and solves the following problems: increase of efficiency of monitoring of educational and scientific-research processes on the basis of systematic measurement of their indicators; improvement of the system of support and maintenance of managerial solutions on the basis of monitoring of university operational performance and efficiency indicators; provision of information support of the quality management system; improvement of wage system on the basis of quality indicator monitoring; increase of reliability of internal and external reported data. The systems are realized in Samara State Aerospace University (national research university) by the personnel of the department of information systems and technologies and information technologies and telecommunication management.

3. Design-automation system of wireless network IEEE 802.11 [№3 за 2012 год]
Authors: Zhukov V.G., Parotkin N.Yu.
Visitors: 10076
The article considers automation design issue related to wireless local computational IEEE 801.11 networks. The problem involves selection of optimal ratio of active network equipment parameters, its settings and location in order to provide maximum access rate for a client to the network in the building and minimize the signal outside the building. Last requirement concerns not only information security but meeting requirement of the Russian law. The article describes legislative and regulatory acts that regulate this field; it also describes the use of the wireless equipment IEEE 801.11. Transmission signal model was improved and formalized to solve the problem of automation design of the network. Based on input parameters that depend on equipment, it makes computation of the signal power in any place of the room, taking into consideration obstacles reducing the power. This helps to make integral estimation of the network type according to assigned deviation of speed inside the room and signal power outside the room. Ideal network shall be characterized by maximum value and, therefore, optimization shall be required. It is recommended to use differential adaptive genetic algorithm. The article describes software system that implements model and algorithm, and it also provides easy graphic interface to work with them. The measurement result revealed that calculated signal power differed from the real power less than for fifteen per cent.

4. Automation design of tools using metal extrusion technology modeling [№3 за 2012 год]
Authors: Агапитова О.Ю., Бывальцев С.В., Zalazinsky A.G.
Visitors: 13541
Present day production systemы involve growing number of chipless shaping processes for low moldable and difficult-to-form metals and alloys. The most promising process to perform works with such materials is hydraulic-mechanical extrusion. Hydraulic-mechanical extrusion process of difficult-to-form metals is studied with automation design system. MATLAB is integrated with solid state modeling package SolidWorks and DEFORM 2D (3D) system. The process modeling was performed; there were calculated basic power consumption features; lasting quality was tested and assembly drawings were produced together with accessories for hydraulic-mechanical extrusion process. Practical application of this software solution was illustrated using model example of extrusion of difficult-to-form aluminum alloy. The model showed how important is the use of active force of friction that reduce extrusion forces.

5. Nearest neighbour search algorithm [№3 за 2012 год]
Author: Гусев Д.И.
Visitors: 12380
The article describes special algorithm for nearest neighbor search in the set of particles in Euclidean space. The algorithm presents the set of particles in the form of linear list data structure; in this list nearest neighbors are placed close to each other, according to sequence numbering of such elements, so, next search of neighboring pair is made through comparison of the next point with following points (according to sequence number) in the list of elements. The algorithm provides search of all neighbors among N particles in O(N2  k) time, where k2 – density coefficient of particle distribution. The article gives experimental dependencies of coefficient k vs. particle distribution density in two-dimensional space, where this feature changes up to 20 units. In described experiments the algorithm has highest effectiveness, when the particles have high concentration: when the concentration is 80 %, it shall be needed, average, 1,3 operations in order to find next pair of neighbors; with concentration 40 % – 1,5 operations; with concentration 20 % – 2,5 operations and 3–4,5 operations with concentration 10–5 %, accordingly. The algorithm is effectively implemented with programming software, which makes it attractive for use.

6. Algorithm of X-graph growth and principles of physics [№3 за 2012 год]
Authors: Коганов А.В., Круглый А.Л.
Visitors: 8147
The work is focused on the current trend at the intersection of theory of automata and algorithms, graph theory, as well as mathematical physics. Over the last years the theory of growing X-graphs is developed, with regard to which the X-graphs by each of their points (X-element) simulate elementary interaction of two initial particles with generation of two resulting particles. Growth of such graph simulates obtaining by the observer of information on physical processes taking place in its space-time neighborhood. The algorithm of incremental formation of X-graph is studied, which meets a set of requirements necessary for discrete space-time model in quantum physics. Special attention is given to implementation of causality principle for the algorithm that makes its interpretation as a physical process observer model to be correct. A new algorithm possesses useful properties, which were not present in the earlier proposed analogous algorithms. The main of them is independence of probability of completion of cause-unbounded by pairs peaks set from the order of introduction of those peaks. The basis of this algorithm is a new way of selection of edges for addition of a new X-element. This is done by means of random paths to the boundary from the randomly chosen peak from the number of peaks which are already present in the graph. Algorithm is interesting from the point of view of the theory of self-organizing of complex growing systems. Its modification and variations of initial states allow models of various systems of pair-wise interactions to be built.

7. Navigation algorithms at the outer surface of international space station model [№3 за 2012 год]
Authors: Maltsev A.V., Mikhaylyuk M.V.
Visitors: 9752
Spaceman moves along ISS outer surface with help of special rails. Station is large, and in order to provide effective and safe movement it is necessary to solve navigation problem, e.g. designing the best route between start and target rails. This article offers route search algorithms according to criteria of minimum length and complexity between two given rails. The article reviews calculation of one or all possible routes that meet selected criteria. Search of a route is made with flow chart, which presents rails in the form of peak and ribs reflect the ways of passing between two neighbored rails. The solution involves oriented sub flow chart, where any route between start and final peaks presents the shortest one (or the least difficulty to pass it) in initial chart. Such algorithms can be used in implementation of navigation systems for simulation training facilities provided for spacemen. Use of such systems in the training facilities increases training effectiveness for those who work outside of station. This article illustrates navigation system in video training facility based on mentioned algorithms. The constructed route between two rails shall be highlighted with specified color. In addition, the article discusses issue related to the future of training facilities concerning development of system that can use virtual reality technology (virtual reality helmet, computer gloves) and navigation system. (The work is supported by RFBR, grant No 10-07-00317).

8. Optimization algorithms of continuous lactic acid biosynthesis [№3 за 2012 год]
Authors: Gordeev L.S., Gordeeva Yu.L., Ивашкин Ю.А.
Visitors: 12270
In the article there are obtained ratios for calculation of continuous lactic acid biosynthesis indicators. The ratios are based on a mathematical model of continuous synthesis in fermenter with agitation. Feature of the model is that each component (substrate, biomass and product) the own expression for specific velocity is written. As the criterion of optimality the productivity Qp on target product (lactic acid) is used. When solving optimal task, at first there are evaluated the channel speed D and the substrate concentration in the output flow, and then the substrate concentration Sf at the inlet of the machine is calculated ensuring maximum productivity. The obtained ratios are used for the development of algorithms of continuous lactic acid biosynthesis optimization. Three variants are considered: absence of limits of the substrate concentration in the incoming flow and the flow value; the maximum possible substrate concentration in the incoming flow and the specified flow value; limit of the flow speed. The second variant is determined by the concentration of the substrate in the incoming stream for optimal conditions, the third is the flow. The second algorithm provides for validation of flow value and the possibility of correction. Numerical results have shown that the greatest value of productivity is achieved for the first variant: Qp=12,42 g/(l h) Sf=46,8 g/l and D=0,5 h-1. Productivity of the second variant: Qp=7,85 g/(l h), Sf=30,39 g/l and D=0,8 h-1. For the third variant: Qp=12,23 g/(l h), Sf=60 g/l and D=0,5 h-1.

9. Architecture of advanced high performance microchips [№3 за 2012 год]
Author: Bobkov S.G.
Visitors: 9100
This article reviews new approaches related to high reliable high performance processors provided for super computers of exaflops range. The article shows basic problems that are encountered in the process of improving computing systems performance, it describes trends in the area of microprocessor performance increase. It is difficult to provide synchronization when the chip size is larger than several millimeters. High consumption rate of synchronization pulse tree in modern high performance 45 nm chips results into use of self- clocked logic together with clocked logic. This work provides pattern of hybrid standard core-based processor, which are implemented based on clocked logic, and coprocessors implemented in the form of thread machine with self- clocked logic.

10. Capability of Matlab package related to distant computation using numerical approach for the problem solution [№3 за 2012 год]
Author: Нгуен Зуи Тхаи
Visitors: 11037
The Web-application is designed on Matlab, Web Server (MWS) and distant computation of various math problems that expands capabilities of the previous numerical approach for laboratory-based practical. This laboratory-based practical represents implementation of numerical technique collection on Matlab provided for cal-culations of functions with given accuracy; non-linear equation solution; solution of simultaneous linear algebraic equations; interpolation of tabulated functions using polynom; approximation of a function; solution of differential equations; numerical integration and numerical optimization of functions. Large library of standard MWS functions used in the technology, can create applications, where Matlab uses World Wide Web to send data to Matlab and display results in a Web-browser. MWS depends on transfer data TCP/IP protocol and it links client and MATLAB. The application works at server and user interacts with it through Web-browser and the user does not need Matlab. Therefore, MWS is also an interact communication service of MatLab with the Web-server Apache. MWS has some advantages. When a network user works with Matlab package, there is no need to install resource-intensive software on local computers, because all computations are made by server. Preparation of the Web-application to work in the net is similar to design of local Matlab application and it includes additional step: design of the Web-interface, which means creation of Web-pages on HTML language. Implementation of the Web-application facilitates teaches’ work, it improves effectiveness of the software in case of distant education.

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