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The problem of search for the necessary information in an unstructured data volume is urgent, because the unstructured information contains a unique potential for the extraction of new knowledge. The complexity of the unstructured data processing is determined by their variety, strong context dependence and dynamic character. The volumes of the stored and transmitted data every year increase. The number of the parameters, characterizing the data, is also steadily increasing. The existing algorithms of the information retrieval systems do not provide flexible functionality for searching through various collections of documents or web pages. The complexity of the subject search in the given document segment is connected with the necessity to pre-configure the parameters of the mathematical models of the search systems. The values of the parameters permitting to improve the relevance of the search query result have been determined. The use of the genetic algorithm and its operation, mutation and crossover operations, and the probabilistic values for each of the operations have been considered. In this study the chromosomes are numerical values of the coefficients represented in a binary form. Based on the results of the work of the genetic algorithm the coefficients for three families of the search systems have been determined: Apache Lucene, Xapian, Sphinx. On the test samples the performance metrics of each of the search systems have been evaluated: accuracy, completeness, exactness, F-measure and errors. According to the results of the assessment, the metric values increase from 7% to 15% and the search error is reduced from 15% to 50%.
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The verification of the cache memory hierarchy in modern SoC due to the large state space requires a huge number of complex tests. This becomes the main problem for functional verification. To cover the entire state space, a graph model of the cache memory hierarchy as well as the methods of generating the formation of the test sequences based on this model have been proposed. The graph model vertices are a set of states (tags, values, etc.) of each hierarchy level, and the edges are a set of transitions between states (instructions for reading, records). The graph model, describing all states of the cache-memory hierarchy states, has been developed. Each edge in the graph is a separate check sequence. In case of the non-deterministic situations, such as the choice of a channel (port) for multichannel cache memory, it will not be possible to resolve them at the level of the graph model, since the choice of the channel depends on many factors not considered within the model framework. It has been proposed to create a separate instance of a subgraph for each channel. The described approach has revealed, in verification of the multiport cache-memory hierarchy of the developed core with the new vector architecture VLIW DSP, a few architectural and functional errors. This approach can be used to test other processor cores and their blocks
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A turn from homogeneous to heterogeneous architectures permits to achieve the advantages of the efficiency, size, weight and power consumption, which is especially important for the built-in solutions. However, the development of the parallel software for heterogeneous computer systems is rather complex task due to the requirements of high efficiency, easy programming and the process of scaling. In the paper the efficiency of parallel-pipelined processing of video information in multiprocessor heterogeneous systems on a chip (SoC) such as DSP, GPU, ISP, VDP, VPU and others, has been investigated. A typical scheme of parallel-pipelined processing of video data using various accelerators has been presented. The scheme of the parallel-pipelined video data on heterogeneous SoC 1892VM248 has been developed. The methods of efficient parallel-pipelined processing of video data in heterogeneous computers (SoC), consisting of the operating system level, programming technologies level and the application level, have been proposed. A comparative analysis of the most common programming technologies, such as OpenCL, OpenMP, MPI, OpenAMP, has been performed. The analysis has shown that depending on the device finite purpose two programming paradigms should be applied: based on OpenCL technology (for built-in system) and MPI technology (for inter-cell and inter processor interaction). The results obtained of the parallel-pipelined processing within the framework of the face recognition have confirmed the effectiveness of the chosen solutions.
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The problem of increasing the operational information exchange of remote control systems, taking into account the delay and corruption of the information in any module and device, included in the route information delivery source to the receiver, has been considered. The inefficiency of forming all components of the working cycle in the common for all modules controller has been shown. The requirements to organization of the information exchange using the Protocol IEC 870-5-101 have been formulated.
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The Global Navigation Satellite System has a huge impact on both the public and private sectors, including the social-economic development, it has many applications and is an integral part of many domains. The application of the satellite navigation systems remains the most relevant in the field of transport, including land, air and maritime transport. The GLONASS system consists of three segments and the operation of the entire system depends on functioning of each component, but primarily, the accuracy of measurements depends on the basis forming of the control segment and management, responsible for forming ephemeris-time information. In the work, the influence of ephemeris-time information on the accuracy of solving the navigation problem by the signals of the GLONASS satellite navigation system has been analyzed. The influence of both ephemeris information and the frequency information, and of the time corrections has been individually studied. The accuracy of the ephemeris-time information is especially important when solving the navigation problem by highly precise positioning method. For the analysis the following scenarios of the navigation problem solving have been formed: using high-precision and broadcast ephemeris-time information, a combination of broadcast (high-precision) ephemeris-time information, and high-precision (broadcast) satellite clock offsets and two scenarios with simulation of the calculation of the relative correction to the radio signal carrier frequency. Based on the study results it has been concluded that the contribution of the frequency-time corrections to the error of location determination is of the greatest importance and a huge impact on the error location, while the errors of the ephemeris information are insignificant
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During functional logic modeling in the process of developing specialized large-scale integrated circuits (LSI) various tasks have to be solved. Currently, the domestic CAD systems lack the error localization subsystem at the stage of the functional-logical design. In the work the existing CAD methods have been analyzed, where the necessary minimum functionality for the error localization technique in the context of improving the «Kovcheg» CAD system had been considered. An effective method of localizing errors based on the requirements of the domestic process and the CAD analysis has been proposed. The formalization of the task of reducing the time for designing LSI has been presented. In addition, a diagram of the data of the developed error localization subsystem has been given, taking into account the features of the “Kovcheg” CAD system. These features, in particular, include the structure of the LSI projects and the peculiarities of storing information in them. When considering the dependence of the LSI development time on the degree of integration of the chip before and after embedding the error localization subsystem in the CAD system, the theoretical shortening of the LSI development time with these simplifications and averages is about 7% in ideal working conditions.
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The complexity of the bibliographic data processing lies in the variety of acceptable standards and the lack of multifunctional software that can be extended for new formats and can process data containing insignificant errors. The work describes the software input/output module dynamic control as a part of the software complex of bibliographic data processing. The analysis of the problem situation within the framework of the subject area, related to multiformat bibliographic data processing, has been carried out. A method of solving the given problem due to placing the processing modules beyond the functional nucleus and due to creating the decomposition extendable system has been proposed. The article includes the general principles of the software model and the implementation details in the programming language Python. The problem of multiple acceptable bibliographic data standards and numerous proprietary formats of the organizations engaged in bibliographic data processing has been solved. The developed software for input/output dynamic control can be applied within the framework of the software complex for bibliographic data processing.
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The most promising way to increase voters’ confidence in the remote electronic voting (REV) procedure is a voting method based on Ethereum blockchain platform. However, the existing solutions using this method faced a range of problems: ensuring the secrecy of the vote and openness of the procedure for society, pressure on the voter and a guarantee of the reliability of the whole system. In this work, a method for constructing a REV is proposed that solves these problems. It is similar in structure to the traditional voting method, using the same principle and processes. The Ethereum blockchain based REV process is described in detail. It was shown that received votes are securely stored in the Ethereum blockchain network, and the correctness of the vote addressing to the selected candidate can always be checked in real time. The description of smart contract algorithm that implements the transfer of vote from voter to candidate using transactions and determines the winner who received the highest number of votes was provided. It was demonstrated that keccak256 hashing algorithm and secp256k1 elliptic curve signatures ensure transactions’ maximum protection, reliability, and non-rollability. The developed REV technique based on Ethereum blockchain platform increases the efficiency of data security and confidentiality, transparency and anonymity of the voting procedure, and solves the problem of coercion. The results of the work have been implemented programmatically and can be used not only in the electoral system, but also wherever there is need of remote voting.
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Optimal control is closely related to the choice of the most advantageous control modes for complex objects, which are described using ordinary differential systems. The problem of optimal control consists in calculating the optimal control program and synthesizing the optimal control system. This problem arises in the applied field of the optimal control theory, in the case when control is based on the principle of feedback and in automatic control systems. Optimal control problems, as a rule, are calculated by numerical methods to find the extremum of a functional or to solve a boundary value problem for a differential equation system. From a mathematical standpoint, the synthesis of optimal control systems is a nonlinear programming problem in functional spaces. In this study the problem of complete controllability of a bilinear control system on the plane was considered. The controllability of bilinear systems with both unlimited and limited control was studied. The evidences of closed trajectory systems controllability theorems were produced. The authors have defined multiple criteria of complete controllability for bilinear system with limited control. The complete controllability conditions of bilinear control system have been proposed with their algebraic reasoning. In the contemporary context of universal robotization of production, completely controllable systems matter in navigation, as well as in modeling of a number of economic and social processes.
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The results of analyzing the examination methods based on 3D rendering in the technological process of the microelectronics items production have been presented. The modification of the algorithms used in these methods has been developed.
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