Abstract: nowadays the field of application of virtual worlds in education grows steadily. Training systems, simulators, role and serious games are the most successful solutions for education in virtual environments. An important part of the above mentioned approaches to education is usage of pedagogical agents (bots), participating in the learning process and helping students to complete educational assignment. The vAcademia virtual world supports implementations of active learning forms through vJS programming language, however bots programming and using was so far unavailable. The article reviews system of bot managing, which allows each user of vAcademia to place and to configure bots, as well as to set their behavior via extended vJS language. Programming of bots’ behavior is based on the objectoriented approach, auto synchronized functions, specifying sequences of asynchronous actions and organization of bot-user interaction through voiced dialogs with pre-defined multiple-choice answers. The interaction with preprogrammed bots can be saved in the form of 3D-record for further viewing, which is highly important in sphere of education.

Keywords: virtual worlds, virtual environments, learning tools, virtuality, bots, programming languages, scripts, built-in programming languages, synchronization, avatars

Abstract: according to the current state standards, “security of information assets” combines protection of four types: physical, technical, legal and cryptographic. This implies that it is a complex concept. Furthermore, in accordance with regulatory documents, protective actions for providing information security are subdivided into organizational and technical measures. Technical protective actions directed at such functions as restricting threats, deterrence, prevention, detection, notification of various events at the facility of informatization, monitoring the state of information assets, error correction, asset recovery system etc. Analysis of the current state of methods and means for the alarm system, which is the most important component of complex system of information security, showed that such systems need to be constantly improved to meet the constantly raising requirements for protection of modern objects of information. Hence it follows that development of mathematical models for calculating the probabilities of unauthorized physical penetration to information assets, forming the integrated system of information security, is an urgent task. To solve the presented problem the article uses methods of information protection, theory of graphs and probability theory. The presented results were obtained using the Maple system of computer algebra. Scientific novelty is in the methods being based on the graph theory and mathematical model of calculating the probability of unauthorized physical penetration to information assets. The model itself is built in three stages on the base of on the specific source data from the estimation of the probability of detecting an unauthorized physical penetration to information assets by alarm system.

Keywords: neograf, acyclic graph, unauthorized physical penetration, technical protection measures, protection of the information assets, orgraph, adjacency matrix, weight matrix, Dijkstra algorithm, somposition of probabilities

Abstract: the article studies methods of determining functional completeness of automated information systems implemented in state social institutions. The author defines a list of automated functions, directly affecting the efficiency of the institution. The article reviews the use of technique based on the Delphi method in expert evaluation. The author considers features of the above mentioned technique as well as Spearman’s rank correlation coefficient for the convergence of expert evaluations. The application of the method is demonstrated on the example of eight different software products for automation of services provisioning by public social institutions. For the first time the article proposes the use of technique based on the Delphi method in expert evaluation with the Spearman’s rank correlation coefficient for the convergence of expert evaluations for evaluating the quality and functional completeness of automated information systems implemented in state social institutions. The analysis described in the article proves that appliance of the technique mentioned above significantly increases the objectiveness of the evaluation, through the use of feedback, analysis of the results of previous stages, as well as their account when estimating the significance of expert opinion.

Keywords: functional completeness, expert evaluation, information systems, Delphi method, Spearman coefficient, methods of peer review, the convergence of expert evaluations, the pair correlation coefficient, coefficient of concordance, Kendall coefficient

Abstract: despite the reduction in corporate market volumes for many branches of commercial banks the center of attraction for the front-office subdivisions increasingly shifts towards retail segment. However, the huge competition in retail forces banks to move towards the unpopular measures of labor intensification and personnel optimization. Under such conditions traditional ways of decision making typical for HR do not work well. The new approaches for retrieving data for decision making must be found, new tools for objective analysis of the situation and developing optimal solutions are needed. The article is devoted to a description of a practical solution to the mentioned above problem. In other words, the subject of the study presented in this paper is HR-process in retail subsystem of a commercial bank. The research of the process of decision making in the HR-subsystem of a commercial bank was held in terms of system analysis. The author developed visual model representing processes typical for the subsystem, revealed the sources of information for decision making. Next, using the built model, based on the simulation techniques and methods of numerical optimization, the technology of automated preparation of recommendations on personnel policy for the retail subsystem of credit institutions was developed. The approach suggested in this paper is fundamentally different from its analogues by the width of coverage of available sources of information and methods of extracting knowledge from databases. Suggested approach for the first time implements simulation modeling of operational risks for retail subsystem of the commercial bank, allowing calculating a complete probability space of outcomes. Thus the higher accuracy and stability calculations is provided compared to Monte Carlo methods with comparable computational cost.

Keywords: computational complexity, simulation modeling, Petri nets, risk, decision making support, personnel management, commercial bank, class of complexity, optimization, Nelder-Mead method

Abstract: the article reviews AND-OR trees with defined cost of arcs or vertices, widely used in artificial intelligence systems. The author describes branch and bound algorithm allowing enumerating all decision trees with cost less or equaling to defined constant value. The complexity of producing another decision tree is O(N), where N is the number of vertices of the AND-OR tree. The article shows a way to use stack for information organization, reducing the memory consumption to O(N) without changing the previous complexity estimate. The article presents software realization of the described algorithm, proving the theoretical evaluation of complexity and amount of the required memory in tests. The effectiveness of search is increased by introduction of the concept of a minimal AND-OR tree cost-constraint subset, which ensures the existence of valid decision trees while descending the decision tree. The decision subtrees are not listed separately but organized in blocs of AND-OR subtress in which all options are possible.

Keywords: artificial intelligence, algorithm, enumeration, AND-OR graph, AND-OR tree, decision tree, AND-OR tree version, cost, cost constraint

Abstract: the article presents a review of formal methods of text attribution. The problem of determining the authorship of texts is present in different field and is important for philologists, literary critics, historians, lawyers. In solving the problem of text attribution the main interest and the main complexity is in the analysis of syntactic, lexical/idiomatic and stylistic levels of text. In a sense, a narrower task is in the text sentiment-analysis (defining the tone of the text). Techniques for solving the task can be useful for identifying authorship of the text. Unfortunately, expert analysis of author’s style is complex and time consuming. It’s desirable to find new approaches, allowing at least partially automate experts’ work. Therefore the article pays special attention exactly to the formal methods of author’s identification and software implementation of such methods. Currently, algorithms of data compression, methods of mathematical statistics, probability theory, neural networks algorithms and cluster analysis algorithms are applied for text attribution. The article describes the most popular software systems for author’s style identification for Russian language. Author attempts to make a comparative analysis, identify features and drawbacks of the reviews approaches. Among the problems hindering researches in text attribution there are a problem of selecting linguostylistic parameters of the text and a problem of selecting sample texts. The author states that there is a need in further researches, aimed at finding new or improving existing methods of texts attribution, at finding new characteristics allowing to clearly separate author’s style, including cases of short texts and small number of sample texts.

Keywords: text attribution, defining authorship, formal text parameters, author’s style, text classification, machine learning, statistical analysis, computer linguistics, identification of author’s style, analysis of textual information

Abstract: in navigation there are two systems of radio navigation: NAVSTAR or GLONASS. Both systems use same approach – determination of the distance from satellites to the object. Distance measuring is performed by measuring the propagation time of the satellite signal to the object. For that purpose the receiver generates pseudorandom code at the exact same moment, when the satellite transmits the signal. On the receiving of the signal by the receiver, the receiver calculates the propagation time as the difference between time of the pseudorandom code generation and the rime of signal receiving. This rises the need to synchronize clocks of the satellite and the receiver. Due to hardware limitations not all receivers can be synchronized with the satellite’s clock. The method presented in the research is based on the analysis of radio navigation systems, principles of functioning and existing techniques of defining object’s coordinates. The article proposes a new way of determining the coordinates, based on the measuring the time difference of signals arrival from different satellites. Because of this there is no need in strict synchronization of the receiver clock and satellite clock, detecting the moment of signal transition from satellite to receiver and use of corrective systems.

Keywords: GPS, delay, trilateration, coordinate determination, satellite navigation, GLONASS, corrective systems, radio navigation, WAAS, range difference method

Abstract: existing software for data statistical analysis (SPSS, Statistica etc.) usually offer for defining correlations just methods applicable for finding linear relationships in numerical data, along with some relation indicators for rank, qualitative and mixed data. However actual relation between quantitative data is often nonlinear. This leads to the fact that present means do not allow identifying such relations, which can lead to false conclusions about the absence of correlation. An universal indicator of present statistical correlation between two rows of numerical data is sample coefficient of determination. There are two approaches to calculated that coefficient: first is based on the approximation of some unknown function with piecewise constant function, second is based on the smoothing available data. The article proposes software realization for both methods in R system. The advantage of this system is in the availability of a large number of specialized library functions for statistical analysis, as well as in writing programs for non-standard tasks. Testing of the developed application on model examples proved their correctness allowing the use for solving practical problems in nonlinear correlation analysis.

Keywords: nonlinear relationship, coefficient of determination, software, R programming Language, data smoothing, correlation ratio, Pearson correlation coefficient, testing, data grouping, piecewise constant function

Abstract: the study uses initial data in form of truth table of three-dimensional function of binary, ternary and mixed logics. Calculation of values of the functions is done by their geometric interpretations, disjunctive / conjunctive normal forms, incompletely connected artificial neural networks and perceptrons with hidden layer. The article in detail reviews the intermediate computation results for all methods mention above. The authors study properties of functions of mixed logic: binary-ternary and 3-2 logics in one-, two- and three-dimensions. The article presents mutually equivalent implementations of logic functions in the form of disjunctive normal form and in the form of incompletely connected artificial neural network. The authors performed replacement of continuous activation function with ternary threshold function. The study includes building disjunctive normal forms, direct synthesis of incompletely connected artificial neural network weights matrix. The perceptron is trained with Back Propagation algorithm. Some conclusions are formed based on the laws of mathematical induction. The article shows that: 1. minimization of the quantity of neurons in perceptron’s hidden layer implicitly leads to the usage of many-valued logics; 2. some functions of binary-ternary logics may be used to build disjunctive forms; 3. a bijective way to convert disjunctive normal form into the form of incompletely connected artificial neural network and vice versa exists; 4. in one-dimensional 3-2 logic there are only eight functions and all of them are listed; 5. proposed structure of incompletely connected artificial neural network may implement any function of ternary logic in any dimensionality.

Keywords: XOR problem, perceptron, separating hyperplane, activation function, perfect disjunctive form, binary-ternary logic, 3-2 logic, ternary logic, neural network training, Back Propagation algorithm