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The work [1] presents the formulation and numerical solution of the problem concerning the unilateral discrete contact interaction of an elastic body and a rigid half-space. However, many parts and components of engineering structures have a pronounced continuous contact within a given surface [2, 3]. In this paper we consider a special case of this option of contact interaction when, the elastic body of finite size, subjected to external forces, is based on a rigid half-space. Contact occurs through a dedicated contact surface, which in general can change their sizes.Developed to solve this problem, a numerical algorithm is a further adaptation and development of the approaches described in [1]. The paper shows results of solving the model problem of the elasticity theory with and without taking friction into account. In the latter case, were additionally obtained numerical data characterizing the convergence of the solution.DOI: 10.7463/mathm.0515.0812348

The paper is aimed at determining the marginal distributions of the estimates of model parameters for a nonlinear dynamic model of the cell population dynamics. The cell population system evolves in the laboratory (in vitro) and comprises two types of cells.Basic estimates of model parameters are obtained on a single limited sample of experimental data. The value of the number of populations of each cell type is obtained from the experiment at equal intervals of time. This paper proposes a technique for determining the marginal distributions of the parameter estimates using numerical modeling.This technique includes the identification of parameters of nonlinear models and test of the obtained model adequacy with base parameter estimates, the identification of the initial data and finding the reference trajectory. The initial data for the trajectory are found using the least squares method, while minimizing the deviation from the experimental trajectory. Data sets on measured densities of the populations at specific points in time are generated using the reference trajectory and the normally distributed random numbers generator. The problem of obtaining estimates of system parameters is solved for each data set. Tests of hypotheses about the marginal distribution of each parameter are carried out based on the calculated set of estimated parameters. To prove hypothesis, the Kolmogorov test is used. The description of a numerical example is included. The obtained marginal distributions of the parameter estimates can be further used to evaluate the probabilities of different scenarios of the population system development.DOI: 10.7463/mathm.0415.0812686

The paper considers the features of finite element technology to determine the temperature state of layered rod structures with complex spatial design. The area of research, on the one hand, is defined by the fact that the rod structures (frames) are so-called “skeletal framework” of aviation, machinery, shipbuilding products and structures for industrial construction and an issue of implementation of most research and industrial projects, strongly promising from the practical point of view, depends largely on the level of reliability, bearing capacity, and general performance of its “skeletal framework”. On the other hand, the laminates have a wide range and unique combination of valuable properties such as high strength, corrosion resistance, electrical conductivity, thermal conductivity, heat resistance, abrasion resistance and many others. The use of layered metal compositions allows to increase the reliability and durability of a large range of parts and equipment and to reduce significantly the consumption of high-alloyed steels and nonferrous metals. A temperature field is one of the main factors to determine the expected performance of multilayer rod structures, operation conditions of which imply intensive thermal loading.The paper shows how within a single finite element model that approximates the spatial design of steel structures consisting of multilayer curvilinear rods, at the stage of discretization in space to take into account the thermo-physical properties of all materials, forming layer of each timber. Using the technique described in the paper has been created a complex of application programs that allows us to solve a wide class of scientific and applied problems, and explore the impact of various structural, technological and operational factors on the temperature state of multilayer rod structures. The paper presents research results of the multilayer rod design. It shows that the high conductivity layer available in the structure provides in all the smaller temperature gradients and a more moderate absolute temperature level.

The traditional approaches to decoding shortened block codes are the padding of received codeword with zeros or correction of the syndrome polynomial values. Such approaches make stream-oriented decoding of continuous input data stream impossible. The paper offers a new technique for decoding the shortened Reed-Solomon codes. Its hardware implementation allows us to provide stream processing, reduce latency in clock cycles, and decrease a required quantity of hardware resources as compared to decoder implementation with padding of received packet with zeros. A distinctive feature of the proposed technique is that the decoder processes a stream of code words of different lengths without changing their structure and insertion of additional delays and that it is possible to use the modules of existing Reed-Solomon decoders for full codeword length. To enable this, a notion of error locator corrector for shortened code is introduced and a technique of their calculation is offered. Error locator correctors are calculated during the reception of a codeword in parallel to syndrome polynomial calculation. Their values allow us to modify the polynomial values of locators and errors at the output of the key equation solver. The paper considers a shortened code decoder that is implemented on the full code decoder modules based on Berlekamp-Massey algorithm, describes architecture of additional modules and required modifications of the algorithm. It shows the way to save hardware resources by using the multipliers in Berlekemp-Massey key equation solver to correct values. The Altera FPGA-based decoder has been tested in and compared to the Reed-Solomon II decoder IP from Altera.

Prospects for space robotics concern both the development of used prototypes to extend the capabilities and the creation of new classes of systems, the operating analogues of which are, currently, unavailable. Thus, a uniqueness of the objects of space robotics, extreme operating conditions, difficulty in full-scale ground work and tests define a variety of design solutions and a wide scope of issues for further theoretical and experimental studies. The paper highlights the tasks successfully solved up to date, involving the space robotics equipment that was used in orbital environment, those of currently solved, involving the robotics equipment that is in use, and the long-term objectives, following from the logic of the space technology development to define the ways of its further development and require a development and creation of new equipment of space robotics. Thus, the development trends of space robotics are largely defined by its history of development, on the one hand, and by a growing demand for the robotic service as applied to the promising objects of space technology, on the other one. The paper considers the trends of space robotics development, which are a consequence of the natural logic of its development and are determined by a demand for advanced objects of space technology in robotic servicing. Highlights the most important elements of a design concept and the creating and operating features of the multipurpose extendable space systems, including those, which have no analogues and prototypes, are rolled into one demand for automation, and associated with their creation, operation, and problems of utilization. The concept of assembly and service autonomous robotic space modules has been under consideration. Within the orbital assembly procedure, the typical dynamic modes, relevant in terms of practical implementation of controlled movement are highlighted.

In this paper, we suggest to use hybrid approach to time series forecasting problem. In first part of paper, we create a literature review of time series forecasting methods based on hybrid neural networks and neuro-fuzzy approaches. Hybrid neural networks especially effective for specific types of applications such as forecasting or classification problem, in contrast to traditional monolithic neural networks. These classes of problems include problems with different characteristics in different modules. The main part of paper create a detailed overview of hybrid networks benefits, its architectures and performance under traditional neural networks. Hybrid neural networks models for time series forecasting are discussed in the paper. Experiments with modular neural networks are given.

Рассмотрена задача маршрутизации транспорта с ограничениями по временным окнам. Требовалось составить план доставки товара клиентам, построив маршруты движения идентичных транспортных средств так, чтобы общая длина пройденного пути была минимальной. Для решения задачи разработан гибридный алгоритм. Он состоит из методов построения исходных решений, муравьиного алгоритма и локального поиска. В муравьином алгоритме в процессе формирования маршрутов разрешается нарушение временных ограничений при условии добавления штрафа в целевую функцию. Предложенный метод показал высокую эффективность при решении задач кластерного типа и задач с долгосрочным горизонтом планирования., The purpose of this paper is to improve the performance of a hybrid method based on ant colony optimization (ACO) that finds approximate solutions of the vehicle routing problem with time windows (VRPTW). In order to solve this problem it is required to design a plan for goods delivery to the customers generating the routes of identical vehicles so that the total travelled distance is minimal. For the VRPTW solving, the hybrid method is developed in which a usage of trial solutions makes it possible to explore the most promising parts of the search space. The initial methods for solution construction, an ant colony optimization (ACO) algorithm and local search are proposed in the framework of the hybrid method. In the ACO algorithm, when generating the routes, it is allowed to violate the time window constraints. A method to restore the feasibility of solutions is implemented within the relaxation scheme under “returns in time” principle. Numerical results for solving all problems with 25, 50 and 100 customers from the Solomon test set are obtained. We provide the results on the time and deviation of the solution of these problems in comparison with the results of other authors. Some problems and their classes were solved much faster by the algorithm proposed in this paper. Relative deviations from optimal values of the objective function for the most complex tasks decrease with increasing decision time. The proposed approach can be considered to be an additional or an alternative algorithm for solving the cluster type and the long-term planning horizon problems of the VRPTW., №5(23) (2018)

The purpose of the paper is the continuation of a cycle of the methodological articles, called to help work of young researchers. The general dissatisfaction with quality and results of research work in an education sphere and pedagogics has been largely caused not only insufficient level of methodological culture of competitors of scientific degrees and researchers-experts, but also their inability to choose a work technology of procedure of research that will be adequate to the purposes, problems and a plan of it. The present article is also devoted to this problem. Methods . The methods of the analysis, synthesis, idealisation, generalisation of author’s experience, a concrete definition and modelling are used. Results and scientific novelty . The general technology of scientific search in an education sphere is presented; the technology is developed on the basis of long-term experience of the Tyumen scientific and pedagogical school, and justified in practice. The author doesn’t take into consideration the rigid technology of algorithmic type which is hardly useful in works of creative character; but in the present case – frame technology that defines the expedient organisation, sequence of stages of work and its corresponding maintenance. The following technology components are described: self-determination of the researcher or research group on the basis of creation and the statement of the developed project of all procedures of search; statement of questions on initial allocation of the problem conducting ideas, a plan-way of its realisation; project performance, its ascertaining and a reformative part, research procedures (the basic stage); summarising, generalisation of the research performed, a writing of the text of report documents, preparation of total publications. Examples of typical errors of the young scientists who do not own the technology of scientific activity are given. Practical significance. Proposed recommendations stated in the paper are designated for teachers-researchers, students, master’s students, post-graduate students and doctoral students, mastering practical methodology of scientific and pedagogical search, and also to the supervisors of studies, aspiring to raise efficiency and content of the tutorial activity.

The aim of the paper is to consider the characteristics of the electronic textbook as the subject of the information-educational environment, which ensures the unity both of the procedural and substantive aspects of training.Results. The evolution of views on the electronic textbook in the course of the expansion and awareness of the didactic potential of information and communication technologies is shown. The structure of the electronic textbook is presented in the paper. It includes the following modules: information (invariant content of education and the expansion of its variability); organizational and procedural (variable-based assignments aimed at acquiring information, as well as a means of reflection and evaluation of results); personal (information and telecommunication means of organizing own knowledge); communicative (the field of information and assessment of interaction); and pedagogical (monitoring cognitive activity of students). The structure has been developed with due regard to the need of independent work of a student with the content of education in information and educational environment.Scientific novelty. The features of the independent work of the student in terms of abundance of information through information and communication technologies are analyzed. Special attention is paid to the development of independent cognitive activity of students, their subject position in education. On this bases, the key position that should be considered during the development of the electronic textbook are specified: cognitive activity is considered as an active process of constructing students’ new knowledge based on earlier formed personal experience; personal experience arises as a result of intellectual and cognitive activity of the student; cognition of something new requires an activity in the field of social communication; the efficiency of absorption of the content of education depends on the conditions of implementation of each student’s value preferences, intellectual capabilities and features.Practical significance. The paper is provided with generalisation of existing visions of electronic textbooks. The research material can be useful both to implementers of such educational means, and the teachers mastering new forms of work with schoolchildren

This paper targets programmers and developers interested in utilizing parallel programming techniques to enhance application performance. The Oracle Solaris Studio software provides state-of-the-art optimizing and parallelizing compilers for C, C++ and Fortran, an advanced debugger, and optimized mathematical and performance libraries. Also included are an extremely powerful performance analysis tool for profiling serial and parallel applications, a thread analysis tool to detect data races and deadlock in memory parallel programs, and an Integrated Development Environment (IDE). The Oracle Message Passing Toolkit software provides the high-performance MPI libraries and associated run-time environment needed for message passing applications that can run on a single system or across multiple compute systems connected with high performance networking, including Gigabit Ethernet, 10 Gigabit Ethernet, InfiniBand and Myrinet. Examples of OpenMP and MPI are provided throughout the paper, including their usage via the Oracle Solaris Studio and Oracle Message Passing Toolkit products for development and deployment of both serial and parallel applications on SPARC and x86/x64 based systems. Throughout this paper it is demonstrated how to develop and deploy an application parallelized with OpenMP and/or MPI.

The paper is devoted to the technique designed for diagnosing the technical university student’s readiness for research activities that is closely related to the research competence structure. Based on the survey results and literature analysis, the authors considered ten primary components of the readiness in question, and analyzed each component along with the corresponding weight value, mean value, and probability density. Consequently, the high level of academic knowledge and motivation for research activity were singled out as the priority components. The paper describes the linear mathematical model, developed for diagnosing student’s readiness for research activities, and presents the minimum, maximum and threshold values of diagnostic assessments, and the relating indicators. The given model can be used as the basic one for developing a test software product for students and research supervisors diagnosing the readiness for research activity

The paper investigates the potential of the intelligent data processing tools presently implemented by economists, marketers and business analytics for solving the economic problems of synthesis and prognostication of financial processes based on quantitative and qualitative indicators. The adaptation of the above methods for pedagogical data processing and implementation in educational process can improve the education management quality and control. The paper presents the theoretical and practical aspects of the intelligent data analysis in pedagogy, the relevance of the problem being substantiated. The author looks at the origination and formation of the intelligent data analysis and gives the estimation examples of qualitative characteristics of teaching process, as well as the students’ personal characteristics based on the Data mining resources. The author recommends the ways for developing the patterns underlying the Data mining methods. The given approach in combination with the modern software tools can provide the data processing related to education management, i.e. pedagogical monitoring, identification of aspects affecting educational outcomes, early correction of educational department activities, etc. В работе рассмотрены возможности существующих средств интеллектуальной обработки данных, которые в настоящее время активно используются экономистами, маркетологами и бизнес-аналитиками и позволяют на основе анализа количественных и качественных экономических показателей решать вопросы синтеза и прогнозирования финансово-экономических процессов. Адаптация данных методов дляобработки педагогической информации и широкое их внедрение в образовательный процесс могут резко повысить качество управления обучением и контроль над ним. В статье обсуждаются теоретические и практические аспекты применения интеллектуального анализа данных в педагогике, обоснована актуальность данной темы. Проанализированы этапы возникновения и становления направления интеллектуального анализа данных. Продемонстрированы примеры оценивания качественных характеристик учения и личностных характеристик студентов с помощью средств Data Mining.Автором предложены подходы к составлению шаблонов, лежащих в основе методов Data Mining, которые в совокупности с применением современных программных средств дают возможность производить обработку материалов педагогического мониторинга, выявлять факторы, оказывающие влияние на результат обучения, своевременно корректировать дальнейшую работу учебного заведения, т. е. осуществлять педагогическое управление.

The paper discusses basic implementation aspects of the Mathematical Education Development Concept, adopted by the Russian Government in 2013. According to the above document, the main problems of mathematical education include: low motivation of secondary and higher school students for studying the discipline, resulted from underestimation of mathematical knowledge; and outdated educational content, overloaded by technical elements. In the author’s opinion, a number of important new mathematical fields, developed over the last years, - the graph theory, discrete mathematics, encoding theory, fractal geometry, etc – have a large methodological and applied educational potential. However, these new subdisciplines have very little representation both in the secondary and higher school mathematical curricula. As a solution for overcoming the gap between the latest scientific achievements and pedagogical practices, the author recommends integration of the above mentioned mathematical disciplines in educational curricula instead of some outdated technical issues. In conclusion, the paper emphasizes the need for qualified mathematical teachers’ training for solving the problems of students’ motivation development and content updates.

The paper deals with the current problem of modern education – developing the many-sided background for preschool children’s learning activities. At the given stage it is necessary to develop the algorithmic skills – the capability of and readiness for solving different kinds of problems in the strict sequence of operations according to the given patterns. Such algorithmic skills have a meta-disciplinary character and can be developed in class and at home. The paper highlights the algorithmic skills components (personal, regulatory, cognitive and communicative) and the key indicators of their formation. The method for developing the algorithmic skills of preschool children is given including the three age related stages: ability to perform the linear algorithms (middle group), working with the branched cyclic algorithms (senior group), mastering the acquired skills and ability to perform some self- dependent tasks (preparatory group). The paper is addressed to the specialists working in the preschool educational sphere: preschool teachers, methodists, psychologists, directors of kindergartens.

The paper is devoted to the communicative competence approach in professional training of physicians on the undergraduate level. The main emphasis is on developing linguistic, sociolinguistic and pragmatic competences while teaching the Russian language and the culture of speech. The paper is aimed at analyzing the requirements of federal state educational standards of the 3rd generation concerning the competences in the humanities which should be developed by medical students in the course of the Russian language and the culture of speech; defining the contents of the «communicative competence» term based on consideration of general European competences in mastering the language and the analysis of lingua-didactic works of modern Russian scientists; identifying the component content of linguistic, sociolinguistic and pragmatic competences of the Russian language and the culture of speech course for medical schools. The research results regarding the analysis and component content of linguistic, sociolinguistic and pragmatic competences of the Russian language and the culture of speech course have been applied while designing the Russian and the culture of speech curriculum, as well as electronic textbooks and manuals for medical students.

The paper investigates invertible linear differential operators. Description of such operators is an important problem, because it is related to transformations of control systems. Namely, a C-transformation is an invertible transformation when the variables of one system are expressed in terms of variables and derivatives of dependent variables with respect to independent variables of second system. The lack of a useful description of C-transformations does not allow developing the theory of their application. C-Transformations of linear systems are represented as invertible linear differential operators. In the case of nonlinear systems, linearizations of C-transformations are interpreted as invertible linear differential operators. Therefore, the study of invertible linear differential operators should be considered as the first step to the description of C-transformations of both linear and nonlinear systems.This paper is the second work devoted to the description of invertible linear differential operators with one independent variable and their generalizations. In the first work, a table of integers was associated to each invertible linear differential operator. These tables were described in terms of elementary geometry. Thus some elementary-geometrical model was assigned an invertible operator. This model was called a d-scheme. Invertible linear differential operators are classified by d-schemes.An invertible operator is not uniquely determined by its d-scheme. It was shown in previous work how to construct some invertible differential operators for a given d-scheme and what mathematical structures still should be given for this construction. However, a description of all invertible operators with a given d-scheme was not there obtained.In this work, a complete description of all invertible linear differential operators with a given d-scheme is obtained. In addition, this result and the results of the first article are generalized to invertible mappings of filtered modules generated by one differentiation. In particular, the linearizations of C-transformations and mappings determined by unimodular matrices are such generalized invertible operators.The results of this paper can be used to describe C-transformations of control systems and to classify such systems.DOI: 10.7463/mathm.0415.0812952

Currently, issues on processing of large data volumes are of great importance. Initially, the Andrews plots have been proposed to show multidimensional statistics on the plane. But as the Andrews plots retain information on the average values of the represented values, distances, and dispersion, the distances between the plots linearly indicate distances between the data points, and it becomes possible to use the plots under consideration for the graphical representation of multi-dimensional data of various kinds. The paper analyses a diversity of various mathematical apparatus for Andrews plotting to visualize multi-dimensional data.The first section provides basic information about the Andrews plots, as well as about a test set of multidimensional data in Iris Fischer’s literature. Analysis of the Andrews plot properties shows that they provide a limitlessly many one-dimensional projections on the vectors and, furthermore, the plots, which are nearer to each other, correspond to nearly points. All this makes it possible to use the plots under consideration for multi-dimensional data representation. The paper considers the Andrews plot formation based on Fourier transform functions, and from the analysis results of plotting based on a set of the test, it draws a conclusion that in this way it is possible to provide clustering of multidimensional data.The second section of the work deals with research of different ways to modify the Andrews plots in order to improve the perception of the graphical representation of multidimensional data. Different variants of the Andrews plot projections on the coordinate planes and arbitrary subspaces are considered. In addition, the paper studies an effect of the Andrews plot scaling on the visual perception of multidimensional data.The paper’s third section describes Andrews plotting based on different polynomials, in particular, Chebyshev and Legendre polynomials. It is shown that the resulting image is well correlated with the original point diagram and the Andrews plots based on the Fourier transform. This allows us to draw a conclusion that the Andrews plots based on the polynomial functions can be used for multidimensional data analysis.The fourth section studies wavelets as a basis for Andrews plotting. It is noted that wavelets have some advantages as compared to the Fourier series. In many areas of the signal analysis a Fourier transform is used for measuring the frequency characteristics of the signal over the entire area. The wavelet transform, on the contrary, is used when it is necessary to measure frequency characteristics in time-localized clusters. Fourier and wavelet transforms are complementary. Fourier transform yields an average frequency with respect to time, and the wavelet transform provides the signal frequency values at any time interval. Based on wavelets Andrews plotting through a set of test data, has shown that it is possible to apply this approach to the graphical representation of multidimensional data.

This paper proposes a new algorithm for community differentiation in social graphs, which uses information both on the graph structure and on the vertices. We consider user's ego-network i.e. his friends, with no himself, where each vertex has a set of features such as details on a workplace, institution, etc. The task is to determine missing or unspecified features of the vertices, based on their neighbors' features, and use these features to differentiate the communities in the social graph. Two vertices are believed to belong to the same community if they have a common feature. A hypothesis has been put forward that if most neighbors of a vertex have a common feature, there is a good probability that the vertex has this feature as well. The proposed algorithm is iterative and updates features of vertices, based on its neighbors, according to the hypothesis. Share of neighbors that form a majority is specified by the algorithm parameter. Complexity of single iteration depends linearly on the number of edges in the graph.To assess the quality of clustering three normalized metrics were used, namely: expected density, silhouette index, and Hubert's Gamma Statistic. The paper describes a method for test sampling of 2.000 graphs of the user's social network \VKontakte". The API requests addressed \VKontakte" and parsing HTML-pages of user's profiles and search results provided crawling. Information on user's group membership, secondary and higher education, and workplace was used as features. To store data the PostgreSQL DBMS was used, and the gexf format was used for data processing. For the test sample, metrics for several values of algorithm parameter were estimated: the value of index silhouettes was low (0.14-0.20), but within the normal range; the value of expected density was high, i.e. 1.17-1.52; the value of Hubert's gamma statistic was 0.94-0.95 that is close to the maximum. The number of vertices with no features was calculated before and after applying the algorithm. With two-third of vertices before using the algorithm their number has fallen to 25-64% depending on algorithm parameter after applying it. The proposed algorithm can be used for clustering the social graphs, but it should be modified to differentiate overlapping communities.

The paper offers a volumetric hydraulic drive structure consisting of an unregulated pump, hydraulic motor, and energy accumulation block with pneumatic-hydraulic accumulator (PHA). Drive control is provided through frequency modification of current arriving at the asynchronous electric drive (AED) from the frequency changer.The paper describes drive advantages when the energy accumulation block is set to allow power accumulation both from the AED and in recuperation regimes with moving outlet drive link with assisting loads. It offers simulation models and computer programmes to analyze a non-stationary movement of the outlet link of volumetric hydraulic drive with frequency control (VHD-FC) with hydraulic motor power supplied from the PHA. The paper examines acceleration regimes of motor axis under different loads and presents PHA energy characteristics and algorithms to find desirable operational non-displaced and constructional accumulator capacities that provide motor outlet link acceleration up to the necessary speed. It presents graphs to show changing motor axis angle speed and PHA-displaced fluid volume as well as energy and PHA power during its discharge versus acceleration time of the motor axis. These dependences are obtained through varying different parameters of the system, namely: inertia, viscous friction, constant load moment, and volumetric displacement.The paper shows that decrease of inertia load and use of hydraulic motor with high volume constants result in the most essentially reduced acceleration time. Setting the PHA allows more than 2.5 times decreasing acceleration time of the motor axis. At the same time, because of the evidently complicated VHD-FC, taking decision on the sound PHA design and parameters must be based on the integration analysis of requirements. These requirements concern the VHD-FC reliability and performance in standard and failure modes as well as the technical-and-economic indexes and operation parameters of drive competitiveness, which are defined by specific designation of engineering hydraulically operating object.

In modern natural sciences, the term of a dynamic system plays an important role and is a common type of mathematical models. Dynamical systems are rarely come to simple functional dependencies. Therefore, qualitative analysis methods of dynamical systems are crucial. In the paper, we consider the simplest type of dynamic systems | continuous dynamical systems described by the systems of ordinary differential equations.Qualitative analysis of differential equations systems usually starts with a search for equilibrium points and a study of the behaviour of a dynamic system in the neighborhood of each equilibrium points. The main attention is paid to the stability of equilibrium, as well as their behaviour type classification. Effective qualitative analysis of differential equations systems is best approached through the bifurcation theory which explains modification of quality in the behaviour of a dynamic system if its parameters are changed.In the behavior of dynamic systems, in addition to the equilibrium points, other bounded trajectories (for example, boundary cycles or separatrix) and their certain conglomerates (such as attractors, invariant tori) play an important role. Investigation of bounded trajectories, in particular, attractors is a difficult task and a lot of scientific articles deal with this problem.In this paper, we study a continuous Lorenz-type system. For this system, all of the equilibrium points are defined and the analysis of equilibrium points types are performed in accordance with the system parameters. The analysis of some bifurcations of equilibrium points are carried out. In particular, the Andronov | Hopf bifurcation is determined and it is shown that it leads to a bifurcation of boundary cycles.DOI: 10.7463/mathm.0315.0789497

The most common problem in the reliability theory is the problem of testing the Cox’s hypothesis. This work is devoted to solving this problem in the case of two progressively censored samples. One of the features is the use of Renyi type statistics, which allows checking the Cox model in case when tests are terminated before all products failure.For testing, there are n1 systems of the first type, which consist of serially connected m1 elements and n2 systems of the second type, which has m2 of the same elements. Considering that the systems are connected in series, the Cox’s hypothesis is tested through non-failure operation times of systems rather than elements themselves. The sample of non-failure operation times is considered as a progressively censored sample from non-failure operation times of elements of the appropriate type. Thus, when the systems fail, the non-failure operation times of all other elements are censored.We suggest the Renyi criterion for testing the hypothesis of proportionality. Functions of elements reliability for each of the two samples are evaluated using the Kaplan-Meier estimates.The paper shows the asymptotic convergence of the proposed distribution of statistics to the standard Renyi distribution. In view of the slow convergence to limiting distributions, a method for calculating the exact distributions of Renyi type statistics is proposed. It is designed to test the Cox’s hypothesis for two progressively censored samples. The proposed method is based on the model of a random walk on a two-dimensional array of cells, and it is described in previous papers. Tables give calculated distribution values for Renyi type statistics for a wide range of values of n1, n2.The paper also suggests the estimate method for Cox model parameter. As an estimate, is considered the value that minimizes the proposed test statistics.DOI: 10.7463/mathm.0515.0816640

The paper describes a distributed algorithm and a structure of the software package for its implementation in which a program for computing the vehicle launch dynamics under interaction with the medium flow is complemented with a program to determine the unsteady hydrodynamic loads by the vortex element method.A distinctive feature of the developed system is that its local (running on a single computing core) LEAVING program to calculate the launch dynamics runs together with concurrent (running on multiple computing cores) MDVDD program to compute the unsteady vortex flow and hydrodynamic loads. The LEAVING program is the main one. It is launched app and then runs the MDVDD program in concurrent mode on the specified number of cores. Using MPI technology allows you to use a multiprocessor PC or a local network of multiple PCs to perform calculations. The equations of launcher spring-mass model dynamics and equations of vortex elements parameters evolution are integrated with the same time step. The interprogram communiaction in the step is provided asynchronously using the OS Windows Event mechanism (Events). Interfacing between LEAVING and MDVDD programs is built using the OS Windows FileMapping technology, which allows a specified data structure to be displayed and read to the fixed memory area.The paper provides analysis of acceleration achieved with parallel processing on different numbers of cores, and defines a parallelization degree of various operations. It shows that the parallelization efficiency of the developed algorithm is slower than in case of calculation of the rigid body flow. The causes of reduced efficiency are discussed.It is shown that the developed algorithm can be effectively used to solve problems on a small number of cores, e.g. on PC based on one or two quad-core processors.

The paper considers the implementing Bellman-Ford and Lee algorithms to find the shortest graph path on a computer system with multiple instruction stream and single data stream (MISD). The MISD computer is a computer that executes commands of arithmetic-logical processing (on the CPU) and commands of structures processing (on the structures processor) in parallel on a single data stream. Transformation of sequential programs into the MISD programs is a labor intensity process because it requires a stream of the arithmetic-logical processing to be manually separated from that of the structures processing. Algorithms based on the processing of data structures (e.g., algorithms on graphs) show high performance on a MISD computer. Bellman-Ford and Lee algorithms for finding the shortest path on a graph are representatives of these algorithms. They are applied to robotics for automatic planning of the robot movement in-situ. Modification of Bellman-Ford and Lee algorithms for finding the shortest graph path in coprocessor MISD mode and the parallel MISD modification of these algorithms were first obtained in this article. Thus, this article continues a series of studies on the transformation of sequential algorithms into MISD ones (Dijkstra and Ford-Fulkerson 's algorithms) and has a pronouncedly applied nature. The article also presents the analysis results of Bellman-Ford and Lee algorithms in MISD mode. The paper formulates the basic trends of a technique for parallelization of algorithms into arithmetic-logical processing stream and structures processing stream. Among the key areas for future research, development of the mathematical approach to provide a subsequently formalized and automated process of parallelizing sequential algorithms between the CPU and structures processor is highlighted. Among the mathematical models that can be used in future studies there are graph models of algorithms (e.g., dependency graph of a program). Due to the high labor intensity of manual parallelization of sequential computer programs for MISD computer, automatic parallelization becomes a key issue for the development of a new MISD architecture. The paper lays down the foundation for the solution of this task.

To build mathematical models of actuating mechanisms (AM) of robots with linear kinematic structure, J. Denavit and R.S. Hartenberg (D-H) proposed to use a special coordinate system (CS). It uses a matrix of homogeneous transformation and provides clear and unambiguous rules to build mathematical models of robot actuating mechanisms. Developers widely use this approach because of its clarity and binding to AM design parameters. However, its use to describe robots the AM of which has a spatial tree-like kinematic structure revealed the certain hardship.The paper offers a method for building a modified D-H coordinate system. Its using allows to create mathematical models of robot AM, having spatial kinematic structure. The method is based on using both the graphs theory and the known D-H coordinate system jointly.The paper defines concepts of main and auxiliary coordinate systems and the order of their location on the tree-like AM. The values of the modified parameters of D-H are obtained. There its known parameters are complemented by parameters f(i), which determine the father number of the link i, and ns(i), that shows, which son in succession is the link i for the link f(i). An algorithm to form the matrix of reachability and the graph of reachability of the tree-like AM is proposed.It is proved that the use of the modified D-H coordinate system allows us to record in a block-matrix form both kinematic and dynamic equations for all links of the tree-like AM of robot. The use of these equations together with D'Alembert principle allowed us to write the equations of the tree-like AM dynamics of robot in the form traditional for recording the AM dynamics equations with open kinematic structure.Via examples of mathematically described kinematics and dynamics of tree-like AM of specific robots (robot-dog, robot-crab, anthropomorphic walking robot, etc.) the paper shows efficiency of modified D-H coordinate system.Obtained research results of the medical robot AM have shown that the proposed model can be successfully used to describe robots with linear open kinematic structure, which is a special case of tree-like kinematic one.

One of the main reasons for interest in the Levy Laplacian and its analogues such as Levy d'Alembertian is a connection of these operators with gauge fields. The theorem proved by Accardi, Gibillisco and Volovich stated that a connection in a bundle over a Euclidean space or over a Minkowski space is a solution of the Yang-Mills equations if and only if the corresponding parallel transport to the connection is a solution of the Laplace equation for the Levy Laplacian or of the d'Alembert equation for the Levy d'Alembertian respectively (see [5, 6]). There are two approaches to define Levy type operators, both of which date back to the original works of Levy [7]. The first is that the Levy Laplacian (or Levy d'Alembertian) is defined as an integral functional generated by a special form of the second derivative. This approach is used in the works [5, 6], as well as in the paper [8] of Leandre and Volovich, where stochastic Levy-Laplacian is discussed. Another approach to the Levy Laplacian is defining it as the Cesaro mean of second order derivatives along the family of vectors, which is an orthonormal basis in the Hilbert space. This definition of the Levy Laplacian is used for the description of solutions of the Yang-Mills equations in the paper [10].The present work shows that the definitions of the Levy Laplacian and the Levy d'Alembertian based on Cesaro averaging of the second order directional derivatives can be transferred to the stochastic case. In the article the values of these operators on a stochastic parallel transport associated with a connection (vector potential) are found. In this case, unlike the deterministic case and the stochastic case of Levy Laplacian from [8], these values are not equal to zero if the vector potential corresponding to the stochastic parallel transport is a solution of the Maxwell's equations. As a result, two approaches to definition of the Levy Laplacian in the stochastic case give different operators. This situation is different from the flat deterministic case, which is discussed in [11]. It can be expected that the work can be summarized in the non-commutative case of the Yang-Mills theoryDOI: 10.7463/mathm.0515.0820322

The paper presents the results of research that is aimed to improve the reliability of transmission of telemetry information (TMI) through a communication channel with noise from the object of telemeasurements to the telemetry system for collecting and processing data. It considers the case where the quality of received information changes over time, due to movement of the object relative to the receiving station, or other factors that cause changes in the characteristics of noise in the channel, up to the total loss due to some temporary sites. To improve the reliability of transmission and ensure continuous communication with the object, it is proposed to use a multi-channel system to record the TMI. This system consists of several telemetry stations, which simultaneously register data stream transmitted from the telemetry object. The multichannel system generates a single stream of TMI for the user at the output. The stream comprises the most reliable pieces of information, being received at all inputs of the system.The paper investigates the task of constructing a multi-channel registration scheme for telemetry information (TMI) to provide a simultaneous reception of the telemeasurement data by multiple telemetry stations and to form a single TMI stream containing the most reliable pieces of received data on the basis of quality analysis of information being received.In a multichannel registering system of TMI there are three main factors affecting the quality of the output of a single stream of information: 1) quality of the method used for protecting against errors during transmission over the communication channel with noise; 2) efficiency of the synchronization process of telemetry frames in the received flow of information; 3) efficiency of the applied criteria to form a single output stream from multiple input streams coming from different stations in the discussed multichannel registering system of TMI.In the paper, in practical implementation of the multi-channel registering system of TMI, additional effect obtained from applying a method of error-correcting coding TMI correcting omissions and inversion bits [1], is applied, as well as the effect of applying the criteria for the choice of parameters of TMI frame synchronizer [2]. This article presents the necessary and effective criteria for constructing the single output stream of information and to assess the quality of the output stream in various realizations of the multi-channel registering system of TMI.The paper discusses two options for building a multi-channel recording system. The first variant of the system does not use additional methods of error-correcting coding during transmission. The second option for constructing a multi-channel system is based on the use of the developed combination of convolutional codes and low-density parity-check (LDPC) (error-correcting coding method presented in [1]).The paper presents selection criteria of the most significant pieces of TMI input streams and a comparative analysis of the effectiveness of the proposed implementations. It gives a comparative assessment of the effectiveness of the proposed methods for constructing a multichannel recording system of TMI according to the following parameters: 1) bit error rate in the output TMI frame; 2) the percentage of fully reconstructed output frames; 3) the gain defined as the ratio of bit error rate in output TMI output frame for the systems under comparison.

В данной работе были исследованы проблемы разработки универсальных и адаптивных систем анализа данных. На примере построения биомедицинских систем мониторинга состояния здоровья человека были выделены основные особенности работы и построения систем, которые анализируют мультимодальные данные. К основным нерешенным проблемам создания адаптивных систем можно отнести необходимость переконфигурирования системы под входную задачу. Для решения задач переконфигурации была предложена теоретическая стратегия построения адаптивной системы анализа данных. Особенностью предложенной системы является двухуровневая архитектура: независимая референсная система и подсистема, отвечающая за адаптивную работу.Библ. 12, рис. 5., The development of adaptive system has been researched for a decade, but only recently machine learning problems became solvable. In this paper is presented an overview of current smart systems and the problem of development real adaptive and versatile data analysis system. Such system has to analyze multivariate signals of different nature. That is why the overview part is based on examples of biomedical human health monitoring systems (BHMS). BHMS have complex internal structure, to simplify it can be divided into three big tiers: tier of data acquisition, communication and analytics tiers. In the first tier, all data acquisition steps are made, including placement sensors to the specific location. The communication tier is responsible for gathering data from all available hardware and send it via wireless channel to the third layer. The analytical tier is the final destination of acquired data. This layer includes all algorithms which will be used for processing data and interpretation of the results. Such simple division allow us to specify and select our potential field of study and improvements. Specifically, in this paper the analytics tier will be explored and new system architecture will be proposed.The crucial step in the adaptive systems development is solving reconfiguration problem. Nowadays, almost all data analysis systems have specific applicable fields. The main advantages of the latter are that they are robust, fast, but the development of such system can take a lot of time and reconfiguration of currently used systems will allow speed up that process. The reconfiguration is process of creation a specific targeting system from general system setup or currently known system. In this paper we have investigated problems, related with reconfiguration and proposing the theoretical basis for creation the reconfigurable adaptive system. The output structure is two-tier system, which allow to analyze any task from different field of study and then process it in a single setup. Each of the tier is considered as independent components, however the combination of the general reference system (tier one) and training agent subsystem (tier two) creates a highly adaptive system with reconfiguration properties. The reference system itself is a big storage of available algorithms which can be applied for certain problem and the algorithms workflow can be tuned for specific problem. Such adjustments can be made because of system training agent, which main purpose is to process input task and defined which algorithms can be applied. Such task classification problem can be solved by using machine learning algorithms.Since, this paper presents only theoretical basis there is no precise implementation of proposed system. Currently we just gave a small overview of the future development of adaptive and reconfigurable systems.Ref. 12, fig. 5., Стаття висвітлює проблеми розробки універсальних та адаптивних систем аналізу даних. На прикладі побудови біомедичних систем моніторингу стану здоров’я людини виділені основні принципи, притаманні системам, які аналізують мультимодальні дані. До основних невирішених проблем створення адаптивних систем можна віднести необхідність переконфігурації системи в залежності від вхідної задачі. Для розв’язання задач переконфігурації була запропонована архітектура адаптивної системи аналізу даних. Особливістю запропонованої системи є дворівнева архітектура: незалежна референсна система та підсистема, яка відповідає за адаптивну роботу.Бібл. 12, рис. 5

This paper analyzes the influence of communication structures on knowledge dynamics. Communication networks theory and methodology are combined with author’s perspective on knowledge, based on autopoiesis theory. Key concepts of network approach are contextualized according to the focus of the paper. We analyze the influence of certain structural factors in communication networks on knowledge fields emergence and development. Relational dynamics and co-evolution of cohesive subgroups in communication networks are analysed as the factors of knowledge transformations in the process of structural coupling between operationally closed distributed cognition systems.

Currently, organization of monitoring complex spatial structures is a particularly relevant task. A classical representative of this class of structures is hydraulic valve ones, in particular floodgates. This class of structures is of particular interest in the fact that systems for monitoring their operational state must meet rather strict requirements because of the monitoring object operation:-structure operates at the air-water media junction;-has long lifetime;-has movable structural elements;-has significantly different operating conditions within the navigation and inter-navigation period.This paper offers to meet requirements through the remote design of deflection measurement (no sensors on the object for monitoring), and evaluate rapidly due to data processing, using reduced models and matrix recovery.The paper presents a technique for selecting the optimum in terms of identifying the current load, the number of measurement points and their relative position. It suggests an approach that allows us to recover the active stresses by measured displacements and determine design elements, the stiffness of which is different from the project stiffness. With available model of design and active forces it is possible to determine a residual error of actual measurements and calculation results by measuring the displacement at the points the number of which exceeds the number of linearly independent loading. This residual error can be interpreted as a result of unsuspected active force or as a deviation of structure rigidity from the project one. This paper gives an upper estimate of stresses and defines possible places of stiffness degradation simultaneously using the same set data.The presented material is based on the test cases and shows the results of choosing measurement points for the floodgate No 7 of Moscow Canal.

The paper considers an issue of object registration in the image through the generalized Hough transform with uncompensated geometric distortions being available. It proposes the method of geometric distortion correction and the method of parameter space normalization. The paper shows that the proposed algorithms require a relatively small amount of computations, but significantly improve the reliability of object detection. The paper may be of interest to professionals working in the field of pattern recognition as well as to graduate and undergraduate students attending lectures on the pattern recognition.

This paper is dedicated to space-temporal radiation analysis of ultra-wideband (UWB) tapered slot antennas (TSA). This antenna type has gained its popularity owing to remarkable UWB performance, low-profile geometry, and essential integration with active RF modules on a common substrate. When TSA is considered as a radiator of UWB pulses, the traditional radiation patterns are no longer fully satisfactory for estimation of its radiation performance. Thus, an antenna should be described as a linear circuit with its pulse response or complex transfer function.Currently, a very few papers reveal such performance features of TSA. Moreover, usually, an antenna model is based on the full-wave CAD model (FDTD, FIT) and, thus, its straightforward evaluation is quite time consuming. However in previous works it was shown that radiation patterns of TSA could be calculated using an approximate two-step approach. Crucial ideas of this method are based on two core stages:aperture field distribution evaluation;radiation performance evaluation using a model of an elementary magnetic radiator in the neighborhood with semi-infinite conducting plane.The first step concerns the full-wave solution of two-dimensional problem on the eigenmode of a slot-line. Thus, unlike a three-dimensional full-wave CAD model, the two-step model enables to evaluate antenna performance in considerably shorter time retaining a high accuracy of results.A mathematical model of the improved two-step approach is comprehensively described in this paper, with special attention being paid to aperture field distribution. A developed calculation algorithm was successfully verified on benchmark models. Calculated results are compared with those of obtained via full-wave simulation. In all cases both methods have shown results of high identity.

The purpose of this paper is to study and find the ways to improve the reliability of onboard laser ranging system (LRS) used to control the spacecraft rendezvous and descent. The onboard LRS can be implemented with optical-mechanical scanner and without it. The paper analyses the key factors, which influence on the reliability of both LRS. Reliability of LRS is pretty much defined by the reliability of the laser source and its radiation mode. Solid-state diode-pumped lasers are primarily used as a radiation source. The radiation mode, which is defined by requirements for measurement errors of range and speed affect their reliability. The basic assumption is that the resource of solid state lasers is determined by the number pulses of pumping diodes. The paper investigates the influence of radiation mode of solid-state laser on the reliability function when measuring a passive spacecraft rendezvous dosing velocity using a differential method. With the measurement error, respectively, 10 m for range and 0.6 m/s for velocity a reliability function of 0.99 has been achieved. Reducing the measurement error of velocity to 0.5 m/s either results in reduced reliability function

The paper considers the issues of designing the two-zone digital microwave sensors for the car alarm systems with high stability characteristics and capable of adaptation to external noise.The existing analog circuit-based microwave sensors for car alarm systems have a number of essential drawbacks:-- high level of intrinsic noise to cause the "false" alarm of response sensors;-- non-stable characteristics caused by the application of analog components at the environmental temperatures from -30 tо +60 С. This requires sensor readjustment during the transition from the summer season to the winter one, that is, essentially, hard to implement;-- uneasy adjustment of a mounted sensor with variable resistors;-- adjustment characterstic nonlinearity and high power consumption;-- impossible to implement the auto-compensation and adjustment algorithms to the repetitive external actions.To overcome abovementioned drawbacks the paper offers a circuit of digital microprocessor-based (PIC12F683 processor) sensor with HF oscillator running in pulse operation mode (pulse ratio 20). It allows 6-8 times decrease of power consumption up to 2.1 mA and twice reduction of noise amplitude. Filters with useful output signal are of digital implementation. This enables us to reduce the number of electric components of sensor in half and to increase characteristics stability.For remote adjustment of sensor (with the key fob of car alarm or by GSM link) 16 gradations of sensitivity are entered for zones of warning and alarm. The reference levels of digital comparators at each gradation of sensitivity are so generated that the sensor has a linear adjustment characteristic (distance of movable object detection versus gradation number).An application of digital signal processing and sensor capability of data exchange with the main alarm module through the bus allows us to implement the original algorithm of automatic correction of sensitivity across the warning zone of sensor. It means that the sensitivity gradually decreases under repetitive external effects (downpour, passing cars in the streets with heavy traffic, etc.) and with returning to the level of preliminary adjustment as the intensity of external effects decreases. Circuit engineering solutions and algorithms of digital signal processing are implemented in line-produced sensors of car alarms with a trademark “Excellent” (Magic Ring Ltd).

The paper considers topical issues of constructing relay systems to control spacecraft attitude and stabilization with no speed sensors (SS) owing to use of internal feedback (IF). To research this system by point methods, e.g. a point mapping method, is difficult because of the need to solve the transcendent equations containing parameters both of control object and of IF. We propose the “diagram of superimpositions" (DS) method based on topological transformations of the phase space and introduction of a relative time, which enables us to solve engineering problems in analysis and synthesis effectively.The concept of the method is based on the assertion that there is an unambiguous dependence between quality of dynamical regimes in the control system and characteristics of IF transition function. To justify the method a simplified mathematical model of spacecraft motion is applied. The following conditions are accepted: perturbations can be neglected; when the control function is activated, the signal of IF is equal to zero. To the phase surfaces are applied topological symmetry transformations, alignment and projection onto the plane with one of its coordinates being the relative time.The paper gives specific examples of systems with aperiodic feedback (AF) for two versions of parameters to satisfy the requirements: I – in quality of self-oscillation mode (by pulse width in the limit cycle); II – in quality of transition process (lack of sliding modes). It is shown that the requirements II and I are contradictory for the system with AF while the sliding modes are unacceptable.It is shown that DS can be used to synthesize the IF to meet requirements of both steady and transient processes consistently. Using the IF it is possible to implement the shutdown laws of the control action on the DS without SS, the same as in case of using the SS. It is shown that in sliding modes transient processes poor in quality can be completely eliminated by choosing the proper form and parameters of the transition function of IF.The DS topological structure features representing object and IF parameters separately are advantages of the method. A character of the transient process and its quality characteristics are defined by the views and parameters of the curvilinear stairs to DS, squeezing into the limiting cycle. An available binary field of curvilinear coordinates makes it easy to do geometric constructions. DS is of great value for analytical solution of problems concerning IF analysis and synthesis.

Шинкарев Александр Андреевич, инженер-программист, ООО «741 Студиос.ру», г. Екатеринбург; sania.kill@mail.ru. A.A. Shinkarev, sania.kill@mail.ru “741 Studios.ru” LLC, Ekaterinburg, Russian Federation This paper describes continuation of the authors’ work in the field of traffic flow mathematical models based on the cellular automata theory. The refactored representation of the multifactorial traffic flow model based on the cellular automata theory is used for a representation of an adaptive deceleration step implementation. The adaptive deceleration step in the case of a leader deceleration allows slowing down smoothly but not instantly. Concepts of the number of time steps without conflicts and deceleration aggressiveness coefficient are introduced. Also in this paper a new step type for models based on the cellular automata is formulated on the example of a stop signal. The new step type unites notification and signalization steps. The new step type extends the concept of the three-stepped unified representation of the traffic flow models based on the cellular automata that was formulated in the previous authors’ work. Рассмотрено продолжение работы автора в области математических моделей транспортных потоков на основе теории клеточных автоматов. На примере переработанного представления многофакторной модели транспортных потоков на основе теории клеточных автоматов представлена реализация шага адаптивного торможения, который в случае торможения впереди едущего транспортного средства позволяет снижать скорость плавно, а не мгновенно. Введены понятия количества тактов без конфликта и коэффициента агрессивности торможения. Также в статье на примере стоп-сигнала сформулирован новый тип шагов для моделей на основе клеточного автомата, который объединяет шаги оповещения и сигнализации. Новый тип шагов расширяет концепцию трёхступенчатого унифицированного представления математических моделей транспортных потоков на основе клеточного автомата, которая была сформулирована в предыдущей работе автора.

The current system of higher education has a focus on fundamentalization, through which students receive the necessary basic knowledge for self-education and the formation of a unified worldview scientific theory in the learning process. Mathematics occupies a special place in the system of Sciences. In training of future teachers of computer technologies mathematics has a significant role and is an important component of basic training. The paper presents the main objectives of mathematical training of students in information science, defines the concepts of "mathematical culture", "math training" and "algorithmic thinking" and describes their relationships. On the basis of mathematical training of students it is possible to form mathematical culture and algorithmic thinking. The paper discusses the main factors influencing low level of quality of mathematical training of future Computer Technologies teachers: a drop in the quality of mathematical training of University entrants, clip-thinking of contemporary students, the low interest of students to studying of disciplines of a mathematical cycle. To solve this problem, tha authors proposed a comprehensive approach based on the combination of methodological approaches, such as differentiated, system and personal-activity. Also, a hypothesis is proposed about the efficient use of information technology in teaching mathematics to increase the level of mathematical training of future Computer technologies teachers.

Purpose. To ensure maximum production of electric power by photovoltaic vacilities, in addition to using highly efficient photovoltaic modules equipped with solar radiation concentrators must use a highly effective power take-off system. This paper is inscribed to solving the problem of a highly efficient and economic power take-off system development. Methodology. To solving the problem, we implemented three stages. On the first stage examines the dependence of electrical power from the intensity of the incident solar radiation. Based on this, the second stage is calculated the DC-DC converter resonant circuit and its working parameters, and developed circuit diagram of DC-DC converter. On the third stage, we carry out an analysis of power take-off system with step up DC-DC converter working. Results. In this paper, we carry out the analysis of working efficiency for photovoltaic facility power take-off system with step-up boost converter. The result of such analysis show that the efficiency of such system in a wide range of photovoltaic energy module illumination power is at 0.92, whereas the efficiency of classic power take-off systems does not exceed 0.70. Achieved results allow designing a circuit scheme of a controlled bridge resonant step-up converter with digital control. Proposed scheme will ensure reliable operation, fast and accurate location point of maximum power and conversion efficiency up to 0.96. Originality. Novelty of proposed power take-off system solution constitute in implementation of circuit with DC-DC converters, which as it shown by results of carrying out modeling is the most effective. Practical value. Practical implementation of proposed power take-off system design will allow reducing losses in connective wires and increasing the efficiency of such a system up to 92.5 % in wide range of photovoltaic energy modules illumination., Проведен анализ работы системы отбора мощности фотоэлектрической станции с использованием повышающего преобразователя. Показано, что коэффициент полезного действия такой системы в широком диапазоне освещенности фотоэлектрического модуля находится на уровне 0,92, тогда как эффективность классических систем отбора мощности не превышает 0,70. Разработана принципиальная электрическая схема регулируемого мостового резонансного повышающего преобразователя с цифровым управлением, обеспечивающая надежность работы, быстрое и точное нахождение точки максимальной мощности и эффективность преобразования до 0,96.

The paper considers the process of algorithmization of reference security models implemented on the basis of the existing formal security models. Main approaches to practical implementation of reference security models in a key of identifying potential areas for improvement are studied. The paper describes the analysis of constraints of models for synthesis based on their formal reference model amenable to implementation in a software algorithm for subsequent practical security analysis of real systems. On the basis of a formalized model graph is built which combines multiple information security vulnerabilities and attack methods of realization of the consequences for the security systems on the basis of which controllable models of real systems can be created. An algorithm of the semi-automatic analysis of the security of corporate automated systems is developed.

The current paper examines the features of a film review as a specific genre from the perspective of discursive pedagogy and the ways of expressing opinions and evaluations as genre and text characteristics. The paper also offers a set of tasks for Linguistics students in which they learn how to write film reviews within a writing course. A film review is considered a polydiscursive text combining different types of discourses: discours of a reviewer, of a film director, of the film itself, of some other people, of some other films, etc. We also treat a film review as an interdiscursive text, as a discourse about another discourse. The specific features of a discursive medium of a film review determine the structure of the film review, which a teacher should bear in mind when working with students. A film review is a secondary text based on the film, its main function is to give opinions on a film. Opinions are represented in all parts of a film review. Different lexical, grammatical and stylistic means of language are employed to express evaluations and opinions. A given set of tasks will teach students how to analyse film reviews and how to create their own film reviews in a foreign language, which helps to form professionally-important communicative abilities of prospective translators

Error detection codes are mechanisms that enable robust delivery of data in unreliable communication channels and devices. Unreliable channels and devices are error-prone objects. Respectively, error detection codes allow detecting such errors. There are two classes of error detecting codes - classical codes and security-oriented codes. The classical codes have high percentage of detected errors; however, they have a high probability to miss an error in algebraic manipulation. In order, security-oriented codes are codes with a small Hamming distance and high protection to algebraic manipulation. The probability of error masking is a fundamental parameter of security-oriented codes. A detailed study of this parameter allows analyzing the behavior of the error-correcting code in the case of error injection in the encoding device. In order, the complexity of the encoding function plays an important role in the security-oriented codes. Encoding functions with less computational complexity and a low probability of masking are the best protection of encoding device against malicious acts. This paper investigates the influence of encoding function complexity on the error masking probability distribution. It will be shownthat the more complex encoding function reduces the maximum of error masking probability. It is also shown in the paper that increasing of the function complexity changes the error masking probability distribution. In particular, increasing of computational complexity decreases the difference between the maximum and average value of the error masking probability. Our resultshave shown that functions with greater complexity have smoothed maximums of error masking probability, which significantly complicates the analysis of error-correcting code by attacker. As a result, in case of complex encoding function the probability of the algebraic manipulation is reduced. The paper discusses an approach how to measure the error masking probability in the case of nonuniform distribution of the input code words. This approach can also be used to study the characteristics of security-oriented codes in case of strong and weak models of algebraic manipulation.

Introduction. With the development of digital technology more attention is paid to making radio-receiving tracks based on SDR technology (Software Defined Radio), which is based on the processing of digitalized radio-frequency signals exclusively by means of software in real time. Moreover the construction ofdata-acquisition systems on one integral chip (SoC) is widely used right now. The main fundamental basis of SoC systems is the FieldProgrammable Gate Array (FPGA). One important step of receiving of radio-frequency signals is a digital down conversion, followed by filtration and repeated decimation. Since processing in DDC is made in a fixed calculation format, than before the immediate implementation of this structure on FPGA, it is necessary to analyze the effect offixed calculation bits on the quality of signal processing. Later it can be used to choose DDC internal calculation bits without sacrificing the set quality of signal processing and hardware resources on its implementation. In the well-known papers, analysis of the effect of signal quantization is reduced to two methods: deterministic and probability methods. Deterministic method gives the top-ofthe-line evaluation of quantizing noise at the output of digital system. Probability method is based on evaluation of quantizing noise dispersion at the output of the device. Evaluation of the signal and the quantization noise in the SDDC based on their PSD. In this section, mathematical expressions were obtained for the construction of PSD signal and the quantizing noise at the output of each of the subsystems of the digital DDC. Criterion for selecting SDDC bit is the relative level of PSD quantizing noise at the output of the digital system. Since the ADC is fixed, the choice of bit computing in SDDC should be such that the total quantizing noise in SDDC would not exceed the ADC quantizing noise at the output of the digital system. Example calculation and construction of PSD signal and quantization noise in Matlab for reception QPSK-signal. In this part of the article an example of the analysis of DDC structure for receiving QPSK- signal was considered. Mathematical Matlab's model has been developed which allows to calculate the PSD of the signal and the quantization noise depending on the internal structure of the SDDC bit based on the formulas of section 2 this paper. These expressions make it possible to construct a PSD noise separately from each SDDC source output, and separately estimate the contribution of each source of quantizing noise to the total noise at the output of the digital system. From these results a decision on the choice of a particular quantization step that depends on the selected calculating bit at each stage of processing was made. Conclusions. Quantizing noise dispersion is not an adequate quality evaluation of processing in multi-stage and multi-rate systems, which include software DDC under review. In such systems the sequential changes of the line, as well as the nature of the spectrum of interfering components, including quantization noise, happen. Therefore in this paper I propose a different approach based on the calculation of the power spectral density (PSD) of the quantizing noise at the output of the device, taking into account the filtering effect of all of its stages and repeated decimation., В данной работе предложен метод анализа влияния шумов квантования на обработку сигнала в цифровом DDC, который основанный на вычислении спектральной плотности мощности (СПМ) шумов квантования по выходу устройства с учетом фильтрующего действия всех его каскадов и многократной децимации. В работе были получены математические выражения для нахождения СПМ сигнала и шумов квантования на выходе каждой из подсистем цифрового DDC. Данные выражения дают возможность выбрать внутренние разрядности вычислений в SDDC таким образом, чтобы суммарный шум квантования в данном устройстве не превышал бы шум квантования АЦП на выходе ЦС. В среде Matlab приведен пример анализа DDC для приема QPSK сигнала., В даній роботі запропоновано метод аналізу впливу шумів квантування на обробку сигналу в цифровому DDC, який ґрунтується на обчисленні спектральної щільності потужності (СЩП) шумів квантування на виході пристрою з урахуванням фільтруючої дії всіх його каскадів і багаторазової децимації. У роботі були отримані математичні вирази для знаходження СЩП сигналу і шумів квантування на виході кожної з підсистем цифрового DDC. Дані вирази дають можливість вибрати внутрішні розрядності обчислень в SDDC таким чином, щоб сумарний шум квантування в цьому пристрої не перевищував би шум квантування АЦП на виході ЦС. У середовищі Matlab наведено приклад аналізу DDC для прийому QPSK сигналу.

The paper presents a unified model for testing tools for object-oriented application development. Based the available papers were identified shortcomings of existing work and identified the following optimal criteria, which shall comply the resulting model: 1. To deep inheritance hierarchies 2. To presents of multiple inheritance hierarchies 3. To presents of abstract classes in the hierarchy 4. To presents of multiple (n-ary) associations 5. To presents of associations with attributes 6. To presents of a composition between classes 7. To presents of recursive associations 8. To presents of associations between classes belonging to the same inheritance hierarchy 9. To presents of association classes 10. To presents between the association class and other classes 11 To presents enumerations in model With a unified graphical language UML class diagram unified model testing. The paper we verified compliance with the resulting implementation of the selected criteria was presented. Currentlythe implementation of applications using object-oriented programming languages and relational databases. To overcome the object-relational mismatch it is necessary to implement object-related mapping patterns presents. The paper presents three methods used to represent the class hierarchy highlighted the advantages and disadvantages of each method. For test the feasibility a unified model chosen development environment SharpArchitect RAD Studio which is designed object applications in C# and are implementing a relational database. The paper presents the developed object model in the form a class diagram showing the interfaces and inheritance relations diagram containing all the tables and columns the resulting database. In the conclusion recommendations on the areas for further development work and identified the need of implement a unified model with other approaches proposed by the authors was used.

The model of cutting plan can be presented as a planar graph for automated system of sheet material cutting process preparation. The aim of such modelling is a definition of the shortest path of a cutter having no parts requiring any additional cuttings. The paper is devoted to a problem of chines postman path constructing for a planar graph representing a cutting plan. This path has a restriction of ordered enclosing (i.e. cycle of passed edges does not contain inside not passed ones). The path satisfying this restriction is also called OE-path. This kind of restriction means the lack of additional cuttings of details. The recursive algorithm for constructing of this type of paths is considered in the paper. It is proved that this algorithm has a polynomial complexity. The developed software allows to solve the problem for an arbitrary planar graph. The software is tested for the typical cases of planar graphs.

International audience; Conformance testing in network engineering is a crucial phase in the development of complex communicating systems. Model-based testing allows to automatize the testing process by generating test suites from a formal specification and to execute them on a real IUT. While many techniques have been developed, their application to test wireless routing ad-hoc protocols still raises many issues. The paper objective paper is to present the node self-similarity reducing the number of inconclusive verdicts often met in traditional MBT

The article deals with the issues of synthesis and analysis of information-measuring and control systems of quadrocopters. The main sensors and modules used to determine the parameters of the coordinates of quadrocopters are given. The speed-controlled electric drives used for control and the features of their choice are considered. The coordinate systems (fixed and mobile) and the kinematic scheme are given, according to which a system of differential equations is presented. The system describes the dynamics of the quadrocopter movement and takes into account the expected smooth movement of the quadrocopter with small roll and pitch angles. A functional scheme and a mathematical model of the information-measuring and control system of the quadrocopter in the form of a block diagram are developed taking into account the influence of delays in the receipt of information from the sensors of the quadrocopter parameters. A special feature of this work is to take into account the specific characteristics of the elements: adjustable electric drives (both direct and alternating current), parameter sensors (barometers, accelerometers, rangefinders, etc.). The paper studies an illustrative algorithm for the operation of the informationmeasuring and control system of the quadcopter. The type and parameters of the controllers of the quadrocopter control systems are determined. Special attention is paid to the settings for the control contours at the corresponding coordinates. The influence of the controllers of the coordinate control systems of the information-measuring and control systems of the quadrocopter on the effects of the interaction of coordinates is considered. The simulation results are presented. The optimal number of control loops for the coordinates of the information-measuring and control systems of the quadrocopter and the optimal type of settings for obtaining smooth transients (without overshoot) and for excluding the interaction of coordinates on quality indicators are determined.

Objectives.The modern world is associated with a clear dependence on it. The number of consumers is growing exponentially. In order to minimize the costs of enterprises, an assumption was made about the rationality of the number of nuclear power plants. When considering the timing of the construction of nuclear complexes, an excessive duration of the manufacture of power and control equipment for nuclear power plants was revealed. In order to reduce time costs, it was proposed to standardize the work of assembly, assembly and packaging production associations.Method.Research in this area was practically not carried out and were, often, of an episodic nature. Initially, it was believed that the operations of the technological process of manufacturing equipment should be rationalized by classical methods, however, in the previous works of the author, a new approach was proposed, based on the analysis of the characteristics of the employee employed in the technical process, the specifics of the type of operational work, as well as various disturbing factors that negatively affect the production time. Then the systematization of the obtained data and their further modeling is carried out.Results. The paper shows the derivation of the final equation for the assembly of the frame of power and control equipment for nuclear power plants. The substantiation of the applied methods was given, the target audience was indicated, the regulatory framework was taken into account. In addition, the results of previous works are shown, on the basis of which the mathematical model was built. Separately, recommendations were given on the additional use of the functions of the resulting equation.Conclusion.The equation obtained in the work makes it possible to calculate with maximum accuracy the time spent on assembling the frame of the power and control equipment for a nuclear power plant. The principles shown in other works can be used in an area that has directionality with minimal model change.

The quality of service (QoS) in networking is the process of managing network resources to reduce packet loss and to lower network jitter and latency. QoS has been widely used in traditional network and can also be implemented in the 5G standard based on a software-defined network (SDN). A traditional network carries several challenges, such as vendor dependency, the complexity of managing a large network, dynamically changing forwarding policies, and more. Software-defined networking is a new networking strategy designed to address the challenges of a traditional IP network, such as high levels of complexity and inability to adapt to the new quality of service requirements in a timely manner. The fundamental idea behind SDNs compared to the conventional networking paradigm is the creation of horizontally integrated systems through the separation of the control and the data plane while providing an increasingly sophisticated set of abstractions. Recently, various SDN-enabled QoS frameworks have emerged that offer many possibilities for network reconfiguration and high-level definition of policies. QoS requirements for 5G networks have been defined on the basis of three main categories of use cases: extreme mobile broadband (xMBB), massive machine type communications (mMTC) IoT/M2M devices, and highly reliable М2М-communication (ultra-reliable machine-type communications – uMTC). This paper analyzes and surveys the QoS based on the openflow protocol method and QoS based on open-source SDN controllers method in 5G network. In addition, we discuss various architectural issues of open-source SDN controllers network and examine their impact on the QoS. Furthermore, we outline the characteristics of the QoS parameters such as latency, availability, reliability, jitter, and bandwidth in the 5G network. Finally, the article discusses and compares parameters of the QoS in 5G determined by world’s leaders in 5G technology.

This paper aims to develop a theory of statistical observation in terms of scientific and methodological approaches to processing big data and to determine the possibilities of integrating information resources of various types to measure complex latent categories (using the example of social comfort) and to apply this experience in practice through the use of the financial situation indicators in forecasting. The authors have built a social comfort model in which the choice of weights for its components is based on a modified principal component analysis. The assessment is based on Google Trends data and official statistics. Google Trends data analysis methods are based on the development of an integrated approach to the semantic search for information about the components of social comfort, which reduces the share of author’s subjectivity; methodology of primary processing, considering the principles of comparability, homogeneity, consistency, relevance, description of functions and models necessary for the selection and adjustment of search queries. The proposed algorithm for working with big data allowed to determine the components of social comfort (“Education and Training”, “Safety”, “Leisure and free time”), for which it is necessary to directly integrate big data in the system of primary statistical accounting with further data processing and obtaining composite indicators. The authors conclude that a stable significant correlation has been found for the “Financial Situation” component, which makes it possible to use it for further calculations and extrapolation of financial indicators. The scientific novelty lies in the development of principles and directions for the integration of two alternative data sources when assessing complex latent categories. The findings and the results of the integral assessment of social comfort can be used by state statistics authorities to form a new type of continuous statistical observation based on the use of big data, as well as by executive authorities at the federal, regional and municipal levels in terms of determining the priorities of socio-economic policy development.