Software & Systems

Journal articles №2 2015

1. Simulation of system indicators to estimate the effectiveness of scientific schools [№2 за 2015 год]
Authors: Ilyasov B.G. (ilyasov@tc.ugatu.ac.ru) - Уфимский государственный авиационный технический университет, Ph.D; Karamzina A.G. (karamzina@tc.ugatu.ac.ru) - Уфимский государственный авиационный технический университет, Ph.D; Fazletdinova Yu.R. (fazletdinova.yulya@gmail.com) - Уфимский государственный авиационный технический университет;
Abstract: 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.
Keywords: information model, scientific school, assessment of efficiency, system indicator, parameter, gradient, coefficient of importance, automated information system, dataflow diagram, research university
Visitors: 13281

2. A problem-oriented editor for design of rule-based knowledge bases [№2 за 2015 год]
Authors: Berman A.F. (berman@icc.ru) - Institute of System Dynamics and Control Theory SB RAS, Ph.D; Grishchenko M.A. (makcmg@icc.ru) - Institute of System Dynamics and Control Theory SB RAS; Nikolaychuk O.A. (nikoly@icc.ru) - Institute of System Dynamics and Control Theory SB RAS, Ph.D; Yurin A.Yu. (iskander@irk.ru) - Institute of system dynamics and control theory SB RAS, National Research Irkutsk State Technical University, Ph.D;
Abstract: The paper describes a modification of the universal editor for design of rule-based knowledge bases. The de-scribed modification of the editor is intended for assessment of technical conditions and operating life of petrochemical equipments. The article also presents architecture, main functions and a structure of files for configuration of the editor. The feature of the modified editor is a semantic layer. This layer provides setup of the editor according to the features of subject domain as well as its integration with inference engines. This provides the ability to test developed knowledge bases . The semantic layer is implemented as a set of templates describing facts and rules (cause-and-effect relations) in prob-lems of technical conditions and operation life assessment. The templates allow abstracting from the syntax of knowledge representation languages (programming languages for knowledge bases, in particular, CLIPS – C Language Production Sys-tem). The second part of the semantic layer is the algorithms that provide dynamic creation (generation) of elements of user interface. The editor is used for developing knowledge bases to examine industrial safety of petrochemical equipments. Application of the editor reduces the participation time of a knowledge engineer in the process of design a knowledge base and provides opportunities for experts to complement the knowledge base in the operation of the expert system.
Keywords: assessment of technical conditions and operation life, code generation, CLIPS, semantic layer, problem-oriented editor, knowledge base
Visitors: 11554

3. Web-oriented component of an expert system [№2 за 2015 год]
Authors: Korshunov S.A. (grey.for@gmail.com) - Institute of System Dynamics and Control Theory SB RAS; Pavlov A.I. (asd@icc.ru) - Institute for System Dynamics and Control Theory Siberian Branch of RAS, Ph.D; Nikolaychuk O.A. (nikoly@icc.ru) - Institute of System Dynamics and Control Theory SB RAS, Ph.D;
Abstract: 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.
Keywords: automation of investigations, knowledge base, qualitative decisions, component, rule-based expert system
Visitors: 14167

4. Implementation of a case-based module for intelligent systems [№2 за 2015 год]
Authors: Zo Lin Khaing (zo.lin2010@mail.ru) - National Research University “MPEI”; Ar Kar Myo (arkar2011@gmail.com) - National Research University “MPEI”; Varshavskiy P.R. (VarshavskyPR@mpei.ru) - National Research University “MPEI”, Ph.D; Alekhin R.V. (r.alekhin@gmail.com) - National Research University “MPEI”;
Abstract: The paper considers important problems of applying a case-based approach in modern intellectual (expert) sys-tems. In particular, in decision support systems focused on assistance to a decision maker when managing complex objects and processes under uncertainty in input data and expert knowledge. Using the mechanisms of plausible reasoning and Case-Based Reasoning (CBR) is directed to expanding the scope of application of intelligent systems under uncertainty as well as reducing time to find solutions. To implement a case-based approach, the authors propose a network (ontological) representation model of cases and hy-brid case retrieving algorithm which is based on the structural mapping theory and the nearest neighbor method. In addition, the paper discusses the possibility of optimizing (reducing) a knowledge base (use case base) of a case-based system (CBR system) using clustering methods. The article proposes CBR system architecture based on the proposed case-representation model and retrieving and opti-mization algorithms for a precedent base (accumulated experience of the system). The authors describe the features of soft-ware implementation of the basic modules of CBR-system prototype in MS Visual Studio 2010 using the Protégé ontology editor for MS Windows. Effectiveness evaluation of the proposed approach and developed software has been carried out on several test data sets offered by the Department of Computer Science, University of California (UCI Machine Learning Re-pository).
Keywords: methods of clustering, structural analogy, case-based reasoning approach, plausible reasoning, intelligent systems
Visitors: 15578

5. Ambiguous semantics and incorrectness when working with C# threads [№2 за 2015 год]
Authors: Billig V.A. (Vladimir-Billig@yandex.ru) - Tver State University, Ph.D;
Abstract: Modern processors are multi-core. Increasing computing power by increasing the number of pro-cessors and the number of cores in each processor will only be progressing. Changing of hard leads to changing soft. As a result, parallel computing becomes one of the main directions of modern programming. When programming in C#, parallel computing is supported by the mechanism of threads created by an oper-ating system. You can create a thread object of the Thread class and associate a certain piece of code with it. It seems natural that when you create a program object of Thread class, the operating system creates a physical thread which will execute the code. For example, it occurs with file objects – creating a file object in the pro-gram leads to the creation of a physical file. The article shows the situations when the “natural” semantics takes place, as well as the situations when crea-tion of program thread does not create the physical thread. The author provides recommendati ons for optimizing the degree of parallelization in recursive methods and in methods without recursion. The research has made it possible to detect the situation when interaction of two important mechanisms (threads and anonymous methods) leads to incorrect work. The constructed examples show incorrect work of anonymous methods when paralleling.
Keywords: anonymous method, recursion, thread, multi-thread programming, parallel computing, c#
Visitors: 10474

6. Expert system for monitoring of technological processes [№2 за 2015 год]
Authors: Burov A.N. (explorer@list.ru) - Tver State Technical University; Kalabin, A.L. (alex.ka.86@gmail.com) - Tver State Technical University, Ph.D; Kozlov A.V. (alex.ka.86@gmail.com) - Tver State Technical University, ; Pakshver E.A. (ea.pakshver@yandex.ru) - Holding Company “Kompozit”, Ph.D;
Abstract: The authors describe an expert system for technologists who work in polyacrylonitrile fibers production. It can help to process and analyze data. The expert system is a part of a larger software system for monitoring technological pro-cesses. The aim of the monitoring system is to gather, store and process data about the state of technological process parame-ters. The expert system analyses data stored by the monitoring system. It consists of two parts: the module for rule creation and the module for rule checking. The module for rule creation allows technologists to store their knowledge as a set of rules in a database. This feature helps to store technologists experience and pass it to other specialists. Every rule includes IF and THEN parts. The IF part contains various logical conditions. The THEN part has conclusion that should be made if logical conditions are true. The system allows creating complex rules based on other simple rules. The module for checking rules al-lows specialists to apply some rule to data set and check logical conditions against that data. The article describes system ar-chitecture and its place in the monitoring system. The work of the system is demonstrated on data from the real process of correlation assessment.
Keywords: control management, diagnostics, technological process, the automated information system, expert system
Visitors: 14699

7. Formal model development for a process of finding solutions by the modified Rete algorithm for fuzzy expert systems [№2 за 2015 год]
Authors: Zaw Min Htike (zawgyi86@gmail.com) - National Research University “MPEI”; Mikhailov I.S. (fr82@mail.ru) - National Research University “MPEI”, Ph.D;
Abstract: The paper considers the basic concepts of fuzzy production expert systems. This type of expert systems is based on a set of rules presented in terms of linguistic variables. The authors propose a developed Rete algorithm modification for fuzz y rule base. It allows creating rules and solutions in the limited natural language and it provides system acceleration due to a single compu-ting the same conditions in the various rules. The authors proposed a decision tree formal model of a modified Rete algorithm for a fuzzy production knowledge base. The model consists of a set of vertex-conditions, vertex-solutions, relations between vertices and relations describing the fuzzy expert system rules. Rete algorithm modification graph is formed in such a way that in each ca se not a correct rule condition value is calculated, but linguistic variable values in the rule.The proposed algorithm processes rules from the fuzzy rule base and converts them into the formal model of a modified Rete algorithm decision tree. The difference between Rete al-gorithm modification and the classical algorithm is application to fuzzy variables. Therefore, the building of fuzzy truth values of decision tree vertices is performed by fuzzy operators at each stage of the algorithm. It allows formulating the conditions a nd conse-quences in the rule base as well as the solutions in the limited natural language. The same conditions are combined during decision tree construction. It provides acceleration of decision tree processing comparing to the sequential viewing of the expert sys tem rules.
Keywords: rete algorithm modification, fuzzy expert system, fuzzy rule base, rete algorithm
Visitors: 8669

8. The limitation method for verifiable models [№2 за 2015 год]
Authors: Korablin Yu.P. (y.p.k@mail.ru) - Russian State Social University, Ph.D; Shipov A.A. (a-j-a-1@yandex.ru) - Russian State Social University, Ph.D;
Abstract: 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.
Keywords: ctl, ltl, temporal logic formula, Buchi automaton, kripke structure, verification
Visitors: 11502

9. 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. ( i@eivanov.com, eiva@tbricks.com) - The National Research University of Information Technologies, Mechanics and Optics, Tbricks AB; Toropov A.V. (tav@tbricks.com) - The National Research University of Information Technologies, Mechanics and Optics, Tbricks AB; Kosyakov M.S. (mkosyakov@gmail.com, mkosyakov@tbricks.com) - The National Research University of Information Technologies, Mechanics and Optics, Tbricks AB, Ph.D;
Abstract: 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.
Keywords: sampling interval, stacktrace, jemalloc, multithreading, operational characteristics, profiling, memory
Visitors: 9217

10. Software package for cloud virtual environments development [№2 за 2015 год]
Authors: Gribova, V.V. (gribova@iacp.dvo.ru) - Institute of Automation and Control Processes Far Eastern Branch of RAS, Ph.D; Fedorischev L.A. (fleo1987@mail.ru)) - Institute of Automation and Control Processes Far Eastern Branch of RAS, Ph.D;
Abstract: 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.
Keywords: software services, editors, declarative models, ontology, computer simulators, cloud computing, virtual environments
Visitors: 9743

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