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The problem of solving the task of discrete optimization is not completely solved. Lack of publications, scientific developments, algorithms and software products do not give the ability to transfer the mathematical apparatus of solving discrete optimization problems to the class P of computational complexity. All analytical and combinatorial algorithms for solving problems of linear and non-linear optimization are NP completeness. There are developments to improve the efficiency of robotic algorithms, they are filled with requests and actual ones. In this paper, it is proposed to use deterministic and probabilistic methods for forming a priority queue of decision vector components in order to assign positive values to them. After the formation of the variant of the solution, it is possible to vectorize as if the approached solution is taken away from the record value of the goal function, which in exact algorithms is like a solution, which results in a polyp. In this paper has a method for forming a priority line for concretizing the components of the solution vector. The basis of deterministic methods is the idea of a greedy algorithm. The location in the queue is determined by the value of the corresponding component of the cost vector. The appearance of the value of non-visibility in the system of restrictions increases the priority of the component. Behind such a way, another method of determination is modified. Probability assessment probability of priorities is based on the ideas of algorithms in an ant colony and simulated annealing. The scope of probability indicates the significance of the component - a contender for a positive value. A numerical example of a small variability of the task about a knapsack has been introduced, which demonstrates the imitation of a nearby solution. [ABSTRACT FROM AUTHOR]

Copyright of National Academy of Sciences of Armenia Reports / Doklady Nacionalnaâ Akademiâ Nauk Armenii is the property of National Academy of Sciences of the Republic of Armenia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Informatics & Mathematical Methods in Simulation / Informatika ta Matematičnì Metodi v Modelûvannì is the property of Odessa Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Foreign Language Teaching is the property of Az Buki National Publishing House and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The task of path finding by an agent is one of the basic tasks and is of great practical importance. As a rule, this is an optimization task that is solved in the space of the state graph in order to minimize the length of the path. Such a task becomes more difficult and becomes even more popular if it is solved on the basis of one graph space by several agents. In this case, another practically important optimization parameter appears, which is expressed by the number of conflicts between agents. Such an abstract formulation of the task has numerous variants of formalization and a large number of approaches to its solution. In this paper, the main element of the approach is the application of the classic Dijkstra algorithm, which is executed sequentially by each agent. When finding the shortest route, each agent modifies the graph space in such a way as to reduce the probability of conflicts with subsequent agents. This approach is original and a number of computational experiments were performed to verify it using software developed for this purpose. The experiments that were conducted demonstrate the adequate behavior of the main algorithm. The work analyzes the limitations inherent in the proposed approach within the framework of the abstract formulation of the task. The directions of further development of the basic approach have been determined. [ABSTRACT FROM AUTHOR]

Copyright of Radio Electronics, Computer Science, Control is the property of Zaporizhzhia National Technical University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Informatics & Mathematical Methods in Simulation / Informatika ta Matematičnì Metodi v Modelûvannì is the property of Odessa Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Informatics & Mathematical Methods in Simulation / Informatika ta Matematičnì Metodi v Modelûvannì is the property of Odessa Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geomatics & Information Science of Wuhan University is the property of Geomatics & Information Science of Wuhan University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Informatics & Mathematical Methods in Simulation / Informatika ta Matematičnì Metodi v Modelûvannì is the property of Odessa Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Stratum Plus Journal is the property of P.P. Stratum plus and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Sensor Electronics & Microsystems Technologies / Sensorna Elektronika i Microsystemni Tekhnologii is the property of I. I. Mechnikov Odessa National University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nuclear Technology & Radiation Protection is the property of Vinca Institute of Nuclear Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Automatic Welding / Avtomatitcheskaia Svarka is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Very often, outputs provided by GIS functions and analysis are assumed as exact results. However, they are influenced by certain uncertainty which may affect the decisions based on those results. It is very complex and almost impossible to calculate that uncertainty using classical mathematical models because of very complex algorithms that are used in GIS analyses. In this paper we discuss an alternative method, i.e. the use of stochastic Monte Carlo simulations to estimate the uncertainty of flow accumulation. The case study area included the broader area of the Municipality of Cacak, where Monte Carlo stochastic simulations were applied in order to create one hundred possible outputs of flow accumulation. A statistical analysis was performed on the basis of these versions, and the "most likely' version of flow accumulation in association with its confidence bounds (standard deviation) was created. Further, this paper describes the most important phases in the process of estimating uncertainty, such as variogram modelling and chooses the right number of simulations. Finally, it makes suggestions on how to effectively use and discuss the results and their practical significance. [ABSTRACT FROM AUTHOR]

Copyright of Electrical Engineering & Electromechanics is the property of National Technical University, Kharkiv Polytechnic Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the paper the associative analysis as a Data Mining technique is investigated. The properties of the algorithms for extracting the associative rules is analyzed and compared. The associative analysis is used for discovering and exploring hidden and interesting relationships between items in large amounts of data. The extracted patterns are presented in the form of association rules or sets of frequent items. The associative rules are represent in the form IF A then B. For studying of various algorithms is used open source software RapidMiner. [ABSTRACT FROM AUTHOR]

Image formation in gamma-ray cameras is made by defining scintillation coordinates, produced by the absorption of gamma-quanta. By the present time different methods for scintillation coordinates defining have been developed based on previously measured and calculated amplitude-spatial features of a photodetector. The paper gives a method for estimating scintillation coordinates without any prior information. The method is based on approximation of the photodetecor response surface, located at the output window of permanent scintillation detector, on the scintillation light distribution function. For the approximation bicubic smoothing splines were used, which weight coefficients are set based on statistical features of measurement results. The paper proposes the approximation algorithm, taking into account geometry of photodetectors distribution at the output window of detector in the points of trigonal lattice. The algorithm can be applied in gamma cameras and other systems of gamma-rays imaging when using detectors such as gamma cameras. Relatively high computational intensiveness as compared to the Anger's method makes the proposed method more appropriate for off-line processing of accumulated data aimed at improving the image quality. [ABSTRACT FROM AUTHOR]

Despite the wide spread of computing devices and mathematical optimization methods in various fields of knowledge, little attention is paid to optimization of solving the problems of labor safety. In the author's opinion the promising solution is developing the methods of sound-absorbing cover optimization based on non-linear programming, one of which has been the objective of the work. The method for estimation of the optimal cover in premises with multi-tone noise conditions is proposed in the paper. Different noise tones can be absorbed by different materials with the most suitable properties. The method is based on random selection of surface area values of different materials, with further selection of the optimal cover. The paper gives the estimation algorithm and the obtained results using the Mathcad computer program. The estimation results indicate the regularities of achieving the optimum and a significant economic effect. The proposed estimation method and algorithm can be used for taking labor safety measures for noise reduction, namely, sound-absorbing covers design for production facilities. The paper has a scientific novelty, based on random selection of materials surface area values, and practical significance based on economic effect and working conditions improvement. [ABSTRACT FROM AUTHOR]

This paper contains the results of studies of the cognitive model developed information technology interdependence and interrelation of complex technical systems to assess their vulnerability. A general block diagram of a ship interconnectedness of complex technical systems. The interaction of ship power plant units, the power supply system of the ship and ship's auxiliary systems in extreme emergency situations. Based on the results of research developed an information processing model of cognitive functioning marine interdependence of complex technical systems. In accordance with the established algorithm vulnerability assessment information elements of the cognitive model calculated the coefficients of the structural vulnerability of its elements. The calculation results have allowed to identify the most critical elements of the model in terms of reliability. The results of research and development will improve the efficiency of operation of complex technical systems that provide high-quality prediction of the reliability of their operation in extreme emergency situations. [ABSTRACT FROM AUTHOR]

This paper is devoted to steganalysis algorithm determining presence a secret message embedded into digital image which is stored in compressed or uncompressed form. The algorithm is based on the analysis of pairs of colors and uses the method of modifying the least significant bit. [ABSTRACT FROM AUTHOR]

The paper focuses on general method of predictive control of modern multi-service networks, which is a major component includes algorithms for the identification of structural models of regular components (trends) of the observed processes. The general structure for predictive control of aircraft communication systems is described. The general view of the structural identification algorithm is discussed. [ABSTRACT FROM AUTHOR]

Copyright of Refrigeration Engineering & Technology is the property of Odesa National University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Recently we have seen the active penetration of computer algebra systems to the educational process because it allows to form an innovative learning technologies. Almost every branch of mathematics the Maple developed the separate specialized package commands. However, currently these technologies, despite its effectiveness and visibility, for various reasons, are still not common in the classroom. The purpose of this article is to review basic information about the capabilities of computer algebra to solve some common problems of the elementary number theory, and which can be used to solve educational problems. The paper describes the package description commands NumberTheory of the computer algebra system Maple. The methods of solving some common problems in the number theory in Maple. Using discussed the team package Maple a teacher can illustrate the problem solving in the classroom for the subject of the elementary number theory [ABSTRACT FROM AUTHOR]

The paper substantiates the conditions of seismic stability in the rock mass with cavities, on which protected objects are located, under constant seismic effects of mass explosions in quarries. Based on the ray-tracing method, a mathematical model of the interaction between longitudinal and transverse waves with a spherical cavity has been developed. An algorithm has been elaborated for determining the total static and dynamic loads along the spherical cavity perimeter from seismic explosion waves falling on the interface. The regularities of joint action of static loads have been determined, when located above the objects cavity, with allowance for the effect of the mass of cavity ceiling, the mass of the protected object above it and dynamic loads in the rock mass, and under the plane wave front fall on the cavity from different directions. The dependences of the change of total stresses referred to the incident wave stress at the interface of the rock mass and the cavity depending on the coordinate on its surface have been set. It has been established that the most dangerous points of cavity surface, in which destruction is likely to occur, are the cases when the seismic wave front falls on the cavity from the bottom directions typical for blasting operations in deep quarries. Under the arbitrary angles of the wave incidence on the cavity the stresses rearrange along the perimeter, which under different circumstances might lead to the mass breach and the fall of the protected objects, located above it, under the ground. [ABSTRACT FROM AUTHOR]

Copyright of Electrical Engineering & Electromechanics is the property of National Technical University, Kharkiv Polytechnic Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper focuses on new steganographic algorithm development. Proposed algorithm is stable to compression, including high rate compression, and based on singular vectors insensitive of image matrix blocks which corresponding to maximal singular values. Algorithm is polynomial of degree 2. The results of numerical experiments confirm the efficiency of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Algorithms of synchronized pulsewidth modulation (PWM), based on special space-vector-based control scheme (with the use of minimal number of voltage space vectors), have been applied for synchronous control of four neutral-point-clamped (NPC) inverters feeding six-phase (dual three-phase) drive on the base of asymmetrical open-end windings induction motor. It allows providing continuous synchronization and symmetry of the phase voltage of system during the whole control range for any ratio of voltage magnitudes of DC-sources, and for any configuration of DC-sources. Therefore, in this case four inverters of the system can be supplied by reduced number of insulated DC-sources (by one, or by two, or by three DC-sources instead of four DC-sources for standard system topology based on four two-level inverters). MATLAB- based simulations show behaviour of the system at steady-state control modes. References 11, table 1, figures 6. [ABSTRACT FROM AUTHOR]

The article describes the information technology for recognition of the number on the hot metal transfer ladle. Processing stages have been identified and described: preliminary processing, localization and number identification. The filtration and incomplete thresholding by means of global binarization with an automatic choice of a threshold have been analyzed. Localization is executed by a single linkage (the nearest neighbour) method with the modified windowing search algorithm. After localization area has been identified, a segment is generated. Identification is accomplished by means of a unique method, which is based on an indistinct representation of images and their comparison with indistinct standards. Combining in a characteristic point the segment which is being analyzed with a prototype segment kernels are formed. Those are then fractured into blocks. Based on these blocks two fuzzy sets are obtained -- one for the segment that is being analyzed and one for the prototype. For these sets the relative Hamming distance is then calculated. The calculated value shows the degree of similarity of the segments. During the tests it was proved that the Hamming distance for the segments with identical numbers is 0,01÷0,16, whereas for the segments with numbers of different ladles it is 0,26÷0,49, which is enough for a successful identification of a ladle by the image of its number. [ABSTRACT FROM AUTHOR]

A couple of decades ago, data rates on the network were measured in kilobytes per second, and even then, online game developers had some problems with the packet loss and transmission delays. Now the transfer rate is hundreds of times higher, and the problem of delay compensation is even more relevant. For many dynamic online games, a transmission delay of as little as 20 ms can be quite noticeable, negatively affecting the gameplay and emotions of the game, which can repel players. The problem is exacerbated by the fact that along with the need to compensate for the time of delivery of packets, on the client side there are other non-network factors that are beyond the control of developers, which make the total delay 5-10 ms longer. Because of this, the desire to get rid of network delays as much and as well as possible becomes a necessity, and developers are forced to look for optimal ways to solve this problem. The problem statement is as follows: to review the causes of delays in online games and possible solutions, as well as the advantages and disadvantages of certain approaches. The problem is considered at the 4 levels of the TCP / IP network model, as well as at the application level. The approaches are given for the most commonly used protocols for each layer, but basic ideas can be easily transferred to other implementations. The main causes of delays under consideration: propagation delay, router queue delay, transmission delay, and processing delays. This article shows the impact of network delays on the online games and the ways to compensate for them, along with the theory of data transmission protocols in the network and the ways to solve the problems that arise in the development of algorithms. Recommendations for solving the compensation problem can be taken into account when designing and launching online shooters, strategies, etc. Thanks to the given receptions it is possible to minimize the general delay on the transfer of packets in a network, thanks to which the game on the client looks as if the player plays in the Single Player mode. [ABSTRACT FROM AUTHOR]