Software & Systems

Articles of journal № 2 at 2015 year.

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11. Software package for cloud virtual environments development [№2 за 2015 год]
Authors: Gribova, V.V., Fedorischev L.A.
Visitors: 8625
The article describes implementation of the IRVIS software package (Internet development of virtual interactive envi-ronments). IRVIS is designed for development and maintenance of virtual environments based on IACPaaS (Intellectual Applic a-tions, Control and Platform as a Service) cloud platform. The main principles are: automation of a development process; invol ving different experts and designers into the process; cloud services programs. Based on mentioned above principles the authors stated some requirements to IRVIS software package and to its implementing methods. The paper describes the main services of the IRVIS. They are: a structure editor, a graphic editor and an interpreter. The struc-ture editor is applied to develop a declarative model of a virtual environment. The article describes the method of implement ing a structure editor as an output service of IWE (Improved Web Editor) of cloud platform. The graphic editor is aimed to form visual el-ements of the virtual environment model and later add it to the declarative view of the model. The paper considers a method of im-plementing the graphical editor as a client-server cloud service of the IACPaaS platform and a method of applying the multiagent approach with messages system included in this service. The interpreter is designed for starting and operating of the develop ed virtu-al environments, each of them becomes an individual service of the cloud platform. Similar to graphic editor, the paper shows a method of implementing the interpreter as a client-server cloud service of the platform using a multiagent approach. At the end of the paper there are some examples of using the IRVIS software package for creating cloud virtual environments: a computer training simulator with classic ophthalmology methods, a virtual chemical laboratory and a virtual editor of a city district.

12. An estimate of the of interdistrict passenger traffic distribution in electric transport [№2 за 2015 год]
Authors: Druzhinina N.G., Trofimova O.G., Trofimov S.P.
Visitors: 6613
The paper shows the developed analysis system of urban electric transport passenger traffic based on infor-mation about of electronic fare payment and navigation data of mobile unit motion. The objective of the study is to identify the traffic flow under uncertainty based on the mapping information, electronic fare payment (transaction) and the navigation system of the mobile unit motion (the moments of passing through the checkpoints – stops). Thhe authors introduce the con-cept of transactivator as a set of transactions, which allow determining the movement of passengers paying fares by E-card. The paper shows the possibility of “bonding” the transplants transaction set in a single itinerary for a passenger. It solves the problem of “last mile”: it means that unknown place and time of arrival of the passenger is defined. The authors received sample distributions of urban electric transport passenger traffic containing basic information about the movement of passen-ger: time and place of the start and end points of the trip. Estimate of the urban electric transport passenger traffic distribution is carried out between the city administrative regions with reference to the routing scheme of tram movement. The number of stops in each administrative district is different; however this allowed us to determine the direction of passenger traffic movement by districts and crowding of routes that pass through several parts of the city. The analysis is performed for the re-al passenger traffic flow in weekdays and days off. The system works with incomplete input data (only one type of public transport is considered). Based on the grouping of stops by administrative districts, OLAP-cube with information about the route of the passenger is built. Statistical analysis of this cube allows defining the extremes of passenger traffic and the city administration can mitigate these extremes through modernization of urban transport network.

13. An experimental study of the performance impact of jemalloc memory profiler on execution time of multithreaded applications [№2 за 2015 год]
Authors: Ivanov E.Yu., Toropov A.V., Kosyakov M.S.
Visitors: 8039
This paper examines the performance impact of jemalloc memory profiler on execution time of multithreaded applications. Using popular synthetic tests the authors implemented a multithreaded application which allows varying different parameters related to memory allocation. A special criteria is suggested to com-pare and estimate profiling results. Tbricks algorithmic trading system is used to demonstrate that popular syn-thetic tests are not adequate enough to analyze memory profiling impact on operational characteristics of the ap-plication. Studies have shown that inactive profiling doesn’t affect the characteristics while with active profiling its values depend on sampling interval and can decrease manyfo ld. According to our analyses of jemalloc library source code related to memory profiling, the part which takes stacktraces is the main reason of extra overhead during profiling. Thus, we compare performance impact on operational characteristics of the app lication using libunwind and prof-libgcc stacktrace libraries: results of experiments made with libunwind stacktrace library are in average 20 % worse than with prof-libgcc. Based on experimental study we recommend using sampling inte r-val which allows of capturing information of at least 90 % of all allocated memory, while execution time of highly multithreaded applications decreases by less than 5 % in comparison with the disabled profiling. This al-lows analyzing memory allocations of applications while executing in production environment.

14. Simulation of system indicators to estimate the effectiveness of scientific schools [№2 за 2015 год]
Authors: Ilyasov B.G., Karamzina A.G., Fazletdinova Yu.R.
Visitors: 11817
The scientific activity effectiveness of a research university depends on the quality of its function-ing and development control. Such control should be based on knowledge of the current stat e of a research uni-versity. It can be determined by evaluating scientific activity. Practical implementation of the scientific activity evaluation is difficult because of the subjective formation of scientific knowledge and the need to use different methods and indicators engaging experts. To assess scientific activity of a research university the paper proposes to use an integrated assessment of scientific schools effectiveness. A hierarchic system that includes level system of estimating gradients, parameters, system indicators and general integrated assessment is used to calculate i n-tegral evaluation of effectiveness. The authors prove the necessity of creating an automated information system of scientific schools effective-ness evaluation. Its application will allow improving the quality of control at all levels of a research university and providing these levels of control with necessary information. A complex of models using a structural a p-proach to the design of automated information systems is developed. This complex includes dataflow diagrams and diagram “entity-relationship”. A software functional diagram is developed to reflect an interaction of the main subsystems of the automated system.

15. On distance metric for the system of automatic classification of the eee devices by production batches [№2 за 2015 год]
Authors: Kazakovtsev L.A., Stupina A.A., Orlov V.I.
Visitors: 8249
Packaging electronic units of complex technical systems with high quality electronic components is an essential condition of increasing quality of the whole system. Elements of the same type should have equal characteristics, which is achieved if they are produced as one produc-tion batch from a one batch of raw materials. Electronic units vary in the requirements concerning the number of pr o-duction batches of devices. This article considers the problem of discovering the quantity of the production ba tches in a lot shipped by a supplier of electronic devices based on testing results as a problem of cluster analysis. The authors propose using the rectangular metric in the k-means clustering problem. They also show the necessary modification of a local search procedure. The results of running system of EEE devices automatic classification by production batches are given. Such results are provided for a k-median problem with squared Euclidean and rectangular metrics. Tests da-ta of the electronic chips were used as example data. Data dimension is up to 2500 data vectors, each of them contains the results of measurement that are up to 230 parameters. An MDS method (Multidimensional Scaling) was used for visual representation of the multidimensional vectors classification results.

16. A genetic algorithm for computer-aided design of preparatory forging transitions [№2 за 2015 год]
Authors: Kanyukov S.I., Konovalov A.V.
Visitors: 9927
The experience of development and implementation of forging CAPP for different types of hammer and press forgings shows that a considerable part in the list of problems to be solved during computer-aided design is so-called difficult-to-formalize problems. An ex-perienced technologist solves these problems under conditions of noncomputerized designing fairly easily, but CAPP developers have to complement the systems by approximation algorithms and offer users-technologists to make their corrections in solutions obtained in an ac-tive dialogue. This approach supposes that technologist’s production experience is used by systems only in a specific version of a design and is not extended to other versions. At the same time the generated database of technological processes previously designed wit h or without human participation implicitly reflects technologists' production experience and the specific character of forging production at an enterprise. The problem is to use this information when solving the tasks which are difficult to formalize. The application of ideas and methods of the genetic algorithm theory which allow a system to use the experience of previous decisions and to develop itself on this basis while in use seems promising in this case. The paper describes a genetic algorithm developed to solve the problem of designing preparatory transitions in a CAPP system of shaft press-forging. This algorithm has the properties of self-improvement and auto-adjustment to actual manufacturing conditions. This allows saving CAPP users from the necessity of making numerous corrections in the design outputs. The abovementioned approach to the development of genetic algorithms can be applied to solving other difficult-to-formalize tasks of forging design.

17. Decision support system development when determining the level of an enviromental fine of an industrial enterprise [№2 за 2015 год]
Author: Kislyakov I.М.
Visitors: 8605
The article considers a problem of decision support system (DSS) development for taking into account the en-vironmental factor by an administrative center when considering a new investment project, including both opening new man-ufactures and expansion of existing facilities. The author proves the necessity of DSS development. The requirements of the user to DSS are given, as a result there also is its composition: an information component (searching and gathering infor-mation for system operation), a modeling component (mathematical model development and its implementation as a comput-er program), an expert component (the analysis of results obtained in the course of the modeling component, giving recom-mendations). The paper describes the role of every component in DSS. The author gives an example of developed DSS im-plementation which helps an end-user to make searching of exact, objective, science-based result easier. This result should help a territory administration to conduct balanced policy on economic development with minimal damage to the environ-ment. The developed program complex “Ecological balancer” shows an example of the graph which reflects the dependence of an investment project net present value from the rate size of an environmental fine when changing specific emission per unit of new production.

18. The limitation method for verifiable models [№2 за 2015 год]
Authors: Korablin Yu.P., Shipov A.A.
Visitors: 10009
Nowadays software systems become more and more complex and sophisticated, so we need to have some use-ful instruments to check if they fit target specifications, especially if we are talking about large and distributed software sys-tems. The article demonstrates a new method which is the separate stage of verification process of information systems. It is intended to make verification more effective. Since the method is a separate verification step for Model Checking method and can be automated easily, its implementation to an existing technology is not a difficult task. The method is based on the principle saying that the model of all systems contains redundant computational sequences. They are not necessary to be analyzed during the properties verification process and it does not affect the final result. The main goal of this method is to exclude these computational sequences from the original model before certain properties veri-fication. The article provides a detailed description of the proposed method and its efficiency estimation. The theoretical material of the article includes illustrative examples of the method, in particular for distributed software system. The authors believe that using of this method can significantly reduce the number of analyzed sequences in verification process for a given system computational model, and thereby improve the performance of the process.

19. Web-oriented component of an expert system [№2 за 2015 год]
Authors: Korshunov S.A., Pavlov A.I., Nikolaychuk O.A.
Visitors: 12571
The paper discusses problems of expert system component implementation in the form of a web application. This component will allow the experts to solve problems using formed logical rules describing the dynamics of studied pro-cesses. Web-based access to the component will enable public access which is especially important in interdisciplinary stud-ies that require a team work of specialists from different areas of expertise. The component has the following architecture: web-service; module interacting with the database and implementing the programming interface to access the database; knowledge management module for working with the rules and facts; rules editor based on RVML-notation; module of communication with web-service that implements the user interface access to the expert system web-service; database for knowledge base storage (facts, rules and initial conditions). The implementation of the web-service is considered in detail. The paper mentions a description of its functions, architecture and functional modules. The main task of a web-service is to prepare database information (facts and rules) for further processing by engine, i.e. convert it from the generalized form to JESS format. The obtained information will be used to implement inference based on rules and facts. The main modules of web-service are: database interface that implements a software interface to access the database; an inference engine that i m-plements the process of reasoning according to the rules and is presented in the form of a software library imp lementing the JESS engine; conversion unit of the rules and facts from the generalized to engine format, the implementation depends on the engine.

20. Forecasting stock price growth using feedforward neural networks [№2 за 2015 год]
Author: Lesik I.A.
Visitors: 16205
The article considers the problem of predicting stock prices using feedforward neural networks. The author used a single-layer Perceptron (without the hidden layer) and a multilayer perceptron (by Rumelhart) as a basis for the algo-rithms. He also implemented a backpropagation algorithm for training neural networks and optimum value selection of a learning rate parameter for algorithms. The paper specifies the conditions of algorithm convergence (in the sense of rms con-vergence to some constant). There is an estimate for the asymptotic complexity of algorithms. The paper also includes a test and analysis of forecast results using time series of share prices changes dynamics in of Russian power company OAO "Gaz-prom". Traditional methods of estimating prediction accuracy are based on the measurement of the forecast deviation from real data (for example, the calculation of the average absolute percentage assessment (MAPE) or average absolute error (MSE). They do not always make possible to assess forecast quality for stock value dynamics adequately. Stocks are characterized by high volatility since such data needs to determine when the growth and fall will be, and most importantly it is difficult to pre-dict leaps separating stationary periods of value changes. Therefore, this article uses assessment methodology of forecast quality which is an alternative to such methods as MAPE and MSE counting. The results of prediction using the calculation of prediction accuracy and the analysis of the forecast diagram allow mak-ing a conclusion about the possibility of obtaining a reliable forecast of stock growth using feedforward neural networks.

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