Software & Systems

Articles of journal № 4 at 2017 year.

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21. Classification and clustering methods for improving efficiency of case-based systems [№4 за 2017 год]
Authors: Varshavskiy P.R., Ar Kar Myo, D.V. Shunkevich
Visitors: 13052
The article examines topical issues of improving efficiency of case-based reasoning (CBR) systems. Case-based methods and systems (CBR systems) are actively used to solve a number of problems in the field of artificial intelligence (for example, for modeling plausible reasoning (common sense reasoning), machine learning, intellectual decision support, intelligent information search, data mining (DM) and etc.). It should be noted that modern tools for DM, which are widely used in intelligent systems, database and knowledgebase management systems, business ap-plications, machine learning systems, electronic document management systems, etc., do not have advanced CBR tools. The paper proposes to use the modified CBR cycle to increase the efficiency of CBR systems. This cycle allows creating a base of successful (CB) and unsuccessful cases (UCB) based on available expert information (test samples), as well as the k-nearest neighbors (k-NN) modification algorithm for case retrieval. The proposed modifications allow improving the quality of solving DM tasks (in particular, data classification task). In addition, the authors consider the possibility of reducing the number of cases in CB using classification and clustering methods to improve performance of CBR systems. The paper shows computational experiments to estimate the effectiveness of the solutions offered while working on a data set from the UCI Machine Learning Repository. They use CBR system prototype developed in MS Visual Studio in C# language.

22. Applying meta-analysis methods in liver failure diagnosis and treatment [№4 за 2017 год]
Authors: B.A. Kobrinsky, A.I. Molodchenkov, N.A. Blagosklonov, A.V. Lukin
Visitors: 8050
The article considers the principles form the basis of various meta-analysis methods and the main differences of tools for their application. It presents and discusses clinical variants of liver failure and their description in literature of various countries and regions of the world (Russia, Asia, Europe and North America). The authors propose the application of a set-theoretic model, the attributes of which should take into account the features of the character and course of the disease in the different nature of the disease and at different periods of its progress. The obtained data will find use in a subsequent meta-analysis. This stage is the main, it formes subgroups of patients on the similarity of clinical implications and the results of applying different treatment regimens. Choosing the meta-analysis method to estimate the world literature data, this approach will allow offering the most appropriate methods of treatment of the disease in a particular patient depending on the nature of relevant changes in the diagnosis of a certain form of hepatic insufficiency. It will provide a transition (by analogy) to the directed use of certain medical means.

23. A software system for identification of a harmonization degree of creative decisions of intellectual agents [№4 за 2017 год]
Authors: Mutovkina N.Yu., Kuznetsov V.N., Klyushin A.Yu., Semenov N.A.
Visitors: 8342
The article considers an information system for determining a degree of harmonization of creative solutions of intellectual agents. According to the general approach to intelligent multi-agent systems and their purpose, the paper considers interaction between agents when they solve a certain creative task. All creative tasks are complex tasks with information reporting and manipulation algorithms. At the final stage they assume coordination and adaptation procedures taking into account changing external and internal conditions of system functioning and implementation of a solution. The purpose of the study is to identify the most effective agents in solving a problem. It is undeniable that an agent can be effective itself. However, in a team it reduces its effectiveness. Conversely, working in a team helps to increase the agent’s activity, operational efficiency. All agents of the system are equal. The efficiency of each of them is estimated by the same method. Each agent offers its solution of the task. These solutions are compared by harmony. If the level of harmony corresponds to a given one, then such multi-agent system is effective. All agents act together, for the benefit of a common goal, reach it with a given quality or above. Otherwise, a system structure and composition are reviewed. The main goal in this case is finding the composition and structure of the multi-agent system when actions between the agents are the most coordinated, that ensures solving the indicated problems. According to the results of the research, due to intelligence of the agents, they tend to change their psycho-behavioral type depending on time they spend on solving a task. As a rule, increasing a time interval leads to changing a compromise type to deviating or coercive. In other words, agents are characterized by a transition from an optimistic attitude to pessimistic (depressive). To prevent such transitions and “mood changes”, there are certain control actions taking into account the need for an individual approach to each individual agent.

24. Modular computer systems simulation software tool for checking feasibility of their configurations [№4 за 2017 год]
Author: A.B. Glonina
Visitors: 7825
The paper presents a software tool for checking feasibility of real-time modular computer systems (RT MCS) configuration. Integrated modular avionics (IMA) systems are considered as an example of RT MCS. An RT MCS configuration is feasible if all works for all computational tasks complete within their deadlines. The author formulates a set of requirements to configurations feasibility checking tool based on analysis of RT MCS design problems. The review of the existing software tools has shown that none of them satisfies all the requirements. Thus, it has become necessary to develop our own tool that would satisfy all the requirements. The proposed software tool allows simulating RT MCS and obtaining timing diagrams of their operation, which are necessary for feasibility checking. The correctness of the developed models was formally proven due to the chosen mathematical formalism (stopwatch time automata networks). As a model for a given configuration can be built and run automatically, our tool can be used together with the optimal configurations search algorithm. The tool was integrated with the scheduling CAD system into the industrial RT MCS and tested on realistic datasets. The experiments showed that the tool is suitable for practical use. Moreover, it is more efficient then a MCS model that is built into a CAD system for the configurations with long scheduling interval. Furthermore, in contrast with the proposed tool, the CAD system model does not satisfy all the requirements.

25. A software package for nonuniform time series analysis based on continuous wavelet transformation [№4 за 2017 год]
Authors: Prokhorov S.A., A.A. Stolbova
Visitors: 7456
Wavelet transformation is one of the methods of data time-frequency analysis. In practice, the researcher often has to analyse nonequidistant (uneven) time series. For this reason, the paper considers algorithms for their continuous wavelet transformation. The authors propose an algorithm for obtaining an array of transformation even shifts, taking into account uneven source date. It means that they choose the interval of involuntary discretization, determine the number of shifts and then calculate their value. The proposed algorithm is the base for an algorithm of continuous wavelet transformation of nonequidistant time series. The process of estimating transformation coefficients uses only samples of time series that are in the width of a wavelet. The advantage of thу proposed algorithm is that the result of the transformation is an even representation. The developed algorithms are used in a complex of programs. The paper shows the results of experiments for models of nonuniform time series with p-transformation and with “jitter” (with uniform distribution and triangular distribution). The velocity of the algorithm can be increased by taking into account the effective radius of the mother wavelet and calculating its width.

26. A software complex to manage and test a distributed database [№4 за 2017 год]
Authors: N.E. Timofееva, K.A. Polulyakh
Visitors: 10263
The paper considers a software solution to manage and test a distributed database, which also allows making the database distribution transparent to the user. The authors highlight the main theoretical aspects of distributed data storage, namely such concepts as a distributed database, a homogeneous and heterogeneous distributed database, table fragmentation, main criteria of database distribution, a client-server technology of distributed database design. The paper analyzes database test performance and reliability. It also gives database management system performance evaluation criteria that affect data processing speed and algorithmic solutions. The presented topic is relevant due to the lack of necessary tests for testing database management system performance, as well as the lack of a universal software package for distributed database design. The article describes the scheme and structure of server and client parts of the application software package. The authors have developed a software package for managing and testing a distributed database, which allows managing a homogeneous relational distributed database. The features of the application are the ability to test the database management system in all network nodes that participate in the creation of a distributed database, as well as the ability to include any other database management systems using a minimal addition of functionality to the software package.

27. Software suite for modeling a radar recognition system [№4 за 2017 год]
Authors: T.V. Kalinin, A.V. Bartzevich, S.A. Petrov, D.V. Khrestinin
Visitors: 8329
The paper presents a software suite for modeling a radar recognition system that evaluates the influence of different factors on the operating efficiency of the system being its statistical mathematical model. The design of effective radar recognition systems requires applying both theoretical research and methods of mathematical and physico-mathematical modeling. The statistical decision theory is a common methodological basis for solving many radar tasks. Solving the problems of recognizing various objects in the air is also based on the theory of probability and statistics. The software implementation of the statistical model is carried out in MATLAB. The software algorithm has been developed by studying the corresponding theoretical background. The software suite consists of subroutines according to the operating principle of recognition systems. The first subroutine reflects the processes in a measuring unit of a radar station. It allows estimating the influence of unit characteristics on the accuracy of measuring target features. The second subroutine simulates the process of radar recognition and enables to rate its effectiveness depending on the selected characteristics of the measuring radar station unit with a given class alphabet and vocabulary of indicators. The third subroutine allows estimating the information capacity of selected indicators to find the most effective set and create an active vocabulary of indicators. The software application has a user-friendly graphical interface and supports conducting research with the results being saved in a file.

28. A protocol for a decentralized storage with redundant encoding [№4 за 2017 год]
Authors: P.K. Karasyuk, D.S. Miginsky
Visitors: 4882
Many distributed data storages use replication that leads to significant decreasing of the effective disk space. Applying redundant coding methods instead of replication for data safety can solve this problem. Due to CAP theorem, many storages abandon strong consistency in favor of eventual consistency, which is a guarantee that data will be consistent within a finite time after last external modification. The transition from replication to redundant encoding under the eventual consistency paradigm leads to complexity associated with the necessity to keep enough mutually consistent fragments of the code words for recovery. The article proposes a Dynamo-based protocol for distributed data storage. It computes object checksums using Reed-Solomon codes and uses them later for recovery if necessary. It provides the same level of fault-tolerance with lower redundancy. The protocol supports concurrent execution of several read and write operations on the same object. It tracks node failures and considers them in further execution. The protocol allows a fixed number of permanent node failures and arbitrary transitional failures without data loss or denial of service. The protocol was tested in a distributed environment simulator with preselected scenarios of failures and user messages. The article demonstrates the protocol behavior in some of the scenarios.

29. Algorithms of regular time series continuous wavelet transformation: development and software implementation [№4 за 2017 год]
Author: A.A. Stolbova
Visitors: 7915
One of the actively developing directions of data analysis is wavelet transformation. It is used for analyzing medical data, image processing and other purposes. This paper considers methods of calculating coefficients of continuous wavelet transformation of even time series. In the classical approach, calculation of some coefficients is redundant because the value of some wavelets is zero. To remove redundancy, the authors propose using wavelet characteristics in the time domain, which allows obtaining a wavelet window width, wich depends on the given scale. The paper gives the obtained characteristics values of mother wavelets, such as Gaussian wavelets of the 1st to the 8th order, the DOG wavelet and the Morlet wavelet. The proposed algorithm for calculating wavelet values is based on these characteristics. The algorithm allows reducing the number of readings of the used wavelet. For each given scale, there is a determined number of nonzero wavelet values and their calculated values. As a result, we get an array of all wavelet values, which are necessary for transformation. The paper proposes an algorithm for evaluating the coefficients of continuous wavelet transformation. It is based on decreasing repeated calculations of wavelets. The reduction of computations is due to taking into account wavelet invariance regarding a shift. Thus, if we calculate all nonzero wavelet values for all scale once and store it, then it is enough we to refer to the wavelet value by number in array corresponding to the shift. The developed algorithms are implemented as a software package. The paper shows that the proposed algorithm works faster than the classical one without significant loss of calculation accuracy.

30. Rational organization of an application software development process for decision support successful automation [№4 за 2017 год]
Authors: Tikhanychev, O.V., L.V. Makartsev, V.R. Gakhov
Visitors: 7881
Despite a long period of using software solution and development of software development tools, this process itself is still not optimized enough. This is especially important for application software development. The subject area analysis shows that a significant part of the problems related to creating high-quality software is in the organization of application programs development. Currently, there is a wide range of methodologies for software development and software implementation tools: Rational Unifield Process, Microsoft Solution Framework, Extreme Programming, Agile, Capability Maturity Model Integration. The article describes possible approaches to rational organization of the above process using specific software systems, such as Team Foundation Server based on Project Management Body of Knowledge (PMBoK). There are conclusions about the need for automated development organization solutions for organizational and technical issues of software development. At the same time, the only use of the TFS system, as any other product of project management organization, does not solve all organizational problems. The paper states that for successful implementation of such systems it is necessary to organize interaction between all participants, to train and implement all specialists into a software development process. The world practice analysis shows that implementation of the proposed measures can significantly increase the effectiveness of software life cycle development and maintenance, providing a transition from existing “artisanal” programming approaches to industrial software development.

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