Harvester open publications of NAS Ukraine
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Hi-frequency cluster solution of problem of shear waves at a system of orifices in half-infinite isotropic environment with fastened boundary
No full textThe new algorithm of computational solution of stationary dynamic problem of elasticity theory about interaction SH-waves with a system of orifices with random normal cross-section that is located in a half-space with fastened boundary is offered. Boundary problem is minimized to a system of integral equations that is solved computationally. Parallel calculation scheme allows analyzing situations with large number of reflecting orifices. New numerical results are shown
Use of ontologies for personalized search of knowledge for natural language texts
No full textThe paper analyzes the problems of search personalization of information resources and information objects which is based on the construction and use of user task thesaurus. This thesaurus allows the use of knowledge about search domain and structure of information objects represented by some appropriate ontologies. The definitions of semantic search, its subjects and components allow more articulate issues related to the information retrieval in the Web open environment. Software implementation of the proposed approach confirms the effectiveness of its prac-tical use.Prombles in programming 2016; 1: 73-8
Logical consequence relations in logics of monotone predicates and logics of antitone predicates
No full textLogical consequence is one of the fundamental concepts in logic. In this paper we study logical consequence relations for program-oriented logical formalisms: pure first-order composition nominative logics of quasiary predicates. In our research we are giving special attention to different types of logical consequence relations in various semantics of logics of monotone predicates and logics of antitone predicates. For pure first-order logics of quasiary predicates we specify composition algebras of predicates, languages, interpretation classes (sematics) and logical consequence relations. We obtain the pairwise distinct relations: irrefutability consequence P |= IR , consequence on truth P |= T , consequence on falsity P |= F, strong consequence P |= TF in P-sеmantics of partial singlevalued predicates and strong consequence R |= TF in R-sеmantics of partial multi-valued predicates. Of the total of 20 of defined logical consequence relations in logics of monotone predicates and of antitone predicates, the following ones are pairwise distinct: PE |= IR, PE |= T, PE |= F, PE |= TF, RM |= T, RM |= F, RM |= TF. A number of examples showing the differences between various types of logical consequence relations is given. We summarize the results concerning the existence of a particular logical consequence relation for certain sets of formulas in a table and determine interrelations between different types of logical consequence relations.Problems in programming 2017; 1: 21-2
Parallel algorithms for the solving both of non-linear systems and initial-value problems for systems of ordinary differential equations on multi-core computers with processors Intel Xeon Phi
No full textThe paper deals with algorithms of methods for the solving both of non-linear systems (NLS) and initial-value problems for systems of ordinary differential equations (SODE) on multi-core computers. Times required for the solving of various order SNE and SODE are given; acceleration and performance coefficients characterizing the employment of methods being proposed are evaluated, as well. Problems in programming 2018; 2-3: 054-06
Simulation and genetic optimization of control systems by LabVIEW programming
No full textThe procedures for the engineering, synthesis, simulation and targeted implementation of algorithms for solving optimization problems in hierarchical automated control systems require complex objects using a variety of mathematical and software and hardware for research and engineering work. In this article the unification of mathematical and algorithmic support in the form of a unified concept of solving optimal control is proposed. We propose to use LabVIEW software and CompactRIO industrial controller as the unification of software and hardware implementation of mathematical-algorithmic developments, on which developed software tools to solve optimization problems using genetic algorithm.Problems in programming 2018; 2-3: 288-295
Game-theoretic approach to the network security problem
No full textIn this paper we present an overview of the main applications of the game-theoretic approach to the network security. The game theory explores the interaction of rational agents in conflict and uncertainty. Models of game theory are successfully applied in economics, biology, computer networks and many others. Application in the field of security is a relatively new direction that allows us to present the problem of protection in the form of a game and apply advanced analysis methods. We describe main threats and corresponding models and methods of game theory in this field of science. A classification of game-theoretic approaches is proposed and a comparison of existing classifications is made. Denial of service attacks which are one of the most dangerous types of cybercrime are investigated separately. Game models of such attacks are built and the vulnerability of existing defense strategies is analyzed. Possible future trends in the application of the game approach to the problems of cybersecurity are identified and described.Problems in programming 2017; 3: 149-160
Method of construction of parallel systems for fuzzy logical inference based on GPU accelerators
No full textWe examine a new method for constructing parallel hierarchical systems of fuzzy logic inference using multi-tier parallel form of algorithms based on Nvidia GPU accelerators and CUDA technology. The efficiency of application of hierarchical systems of fuzzy inference for development of diagnostic intelligent system is substantiated. We characterize the organization of efficient computations on graphic accelerators with the aim of achieving maximum degree of parallelism in fuzzy hierarchical systems. In particular, the above organization relies on parallelization of rules inside each block of fuzzy rules. An intelligent software system for assessing the quality of startups based on parallel inference architecture that contains Takagi – Sugeno blocks of fuzzy rules is developed. The experiment is conducted to demonstrate acceleration estimates for developed intellectual system for assessing the quality of startups as well as for more complex systems with randomly generated dependencies between blocks of rules. We compare characteristics of the obtained acceleration estimates with corresponding estimates for hierarchical fuzzy systems based on the distributed computing technology and MPI message exchange. The advantages of developed method for construction of parallel fuzzy inference based on GPU are substantiated. Problems in programming 2017; 4: 003-01
Principles and analytical tools for reconstruction of probabilistic dependency structures in special class
No full textWe examine a problem of reconstruction of dependency structure from data. It is assumed that model structure belongs to class of "mono-flow" graphs, which is a subclass of acyclonic digraph (known as DAGs) and is super-class relatively to the poly-trees. Properties of the mono-flow dependency models are examined, especially in terms of patterns of unconditional dependencies and mutual information. We characterize the twin-association evolving among two variables. Specialized methods of inference of mono-flow dependency model are briefly reviewed. To justify correctness of model recovery from data we formulate an assumption of unconditional (marginal) edge-wise faithfulness, perhaps the most reliable one among all simple versions of Causal faithfulness assumption. On the basis of the assumption and the properties of mono-flow dependency models we derive several empirical resolutions for edge identification, which make use 2-placed statistics only. A lot of experiments with artificial data have demonstrated efficiency of the resolutions in that they correctly recover many edges and commit low error rate.Problems in programming 2017; 1: 97-11
Extension of the program synthesis system to analyze large data sets
No full textAnalysis of large data sets is a challenging problem in the modern world. This paper presents an extension of the online dialog designer of syntactically correct programs ODSP for programs designing and synthesis for analyzing large data sets based on Apache Hadoop software. The advantage of the proposed approach is the use of a method that ensures the syntactic correctness of algorithms and programs that were designed. Experiments have been carried out and the operation of the system is illustrated by the example of program designing for analyzing a large meteorological data set. This approach is promising for the scientific research conducting, in particular in the field of meteorology.Problems in programming 2018; 2-3: 068-07
Problem-oriented computer simulators for solving theoretical and applied tasks of human physiology
No full textThe goal of the paper is in overview of specialized mathematical models and computer simulators created for solving both applied and theoretical problems of human physiological systems. Examples of applied models aimed at optimizing of ways for increasing the resistance of a healthy person to prolonged exposure to extreme loads of the environment (physical factors of aerospace flight, as well as changed atmospheric pressure) are described. Along with models constructed within the framework of the traditional physiological paradigm of homeostasis, a model simulating the fight of organism’s different scale mechanisms against energy lack is described. This model is based on the author's concept of coexistence of cells of different specializations in a single organism. The general characteristic of the complex model and software simulator of the organism-scale energy megasystem providing the fight of cells against energy deficit is given. The new physiological concept explained the endogenous mechanisms of circulation optimization and allowed the author to rethink the role of arterial pressure in the functioning of the body. Models of adaptive and pathological hypertrophy of the heart are briefly described. Software simulators are developed for IBM-compatible PC, programs are written in Borland Pascal for Delphi or in C++ for Visual Studio-10 environment.Problems in programming 2017; 3: 161-17