Actual problems of automation and information technology (E-Journal) / Актуальні проблеми автоматизації та інформаційних технологій
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Механічний підхід до моделювання поведінки натовпу
Get PDFIn modern society, the problem of moving large masses of people in the premises is very relevant. With the development of globalization and the rapid growth of the planet's population, the question of studying the laws of the crowd is becoming more acute. In modern cities, population density is very high, even higher in crowded places: public transport, stadiums, concert venues, mass events on the streets of the city, etc. Usually this does not cause problems, but when an emergency occurs (fire, terrorist act), large crowds of people in a confined space become a source of great danger. Modeling and predicting their behavior in these conditions is a very important task in the context of designing buildings and organizing mass events in terms of safety and comfort. The analytical solution of this problem is difficult to obtain not so much because of the complexity of the mathematical model, but because of the large number of unknown parameters and external factors. The approach used in this work is based on potential forces of a social nature and ordinary physical effects such as friction, elastic collisions, and others. This approach originates from the works of famous mathematician Dirk Helbing. As part of this article, we will try to improve this approach and expand the scope of its possible use through the use of path search algorithms on the plane. This will allow the method to be used in places with complex geometry, many inputs and outputs, and to simulate additional effects by varying the parameters of the algorithm. An algorithm for finding the shortest path on the plane A * was chosen as the base one.The purpose of the article is to implement a mechanical approach to modeling the dynamics of the crowd, analysis of its work, modifications, which will expand the scope of its application and improve the accuracy of modeling.The following aspects of the problem were considered in the article: modeling on the basis of a mechanical model of the dynamics of the crowd, the use of algorithms for finding the shortest path on the plane to expand the scope of the model, visualizing the modeling process, estimating the model by quantitative and qualitative parameters.As a result, the implementation of this model was developed, experiments carried out and demonstrated its strengths and weaknesses.В работе представлена реализация механического подхода к моделированию поведения толпы. Проведенные модификации, которые позволили расширить область ее применения и повысить точность моделирования. Проанализированы преимущества и недостатки модифицированной модели и намечены пути дальнейшего улучшения и развития модели с целью повышения ее пригодности к реальным приложений.В роботі представлена реалізація механічного підходу до моделювання поведінки натовпу. Проведені модифікації, які дозволили розширити область її застосування та підвищити точність моделювання. Проаналізовані переваги та недоліки модифікованої моделі та намічені шляхи подальшого покращення та розвитку моделі з метою підвищення її придатності до реальних застосувань
Дослідження методів розв’язання задачі маршрутизації великої розмірності
Get PDFIn this paper, we researched methods for solving a large-scale vehicle routing problem. First, we provided the description of the problem that modern logistic companies encounter during the planning of transportations. As a solution for this problem, we used meta-heuristics and clustering algorithms. Existing studies and publications in the field of large-scale routing were analyzed, giving us the opportunity to assess the quality of the presented meta-heuristics and select those that lead to the best results. The definition of the routing problem is presented, as well as the description of requirements and limitations for the final solution. Then, in the main part of the work, we offer a brief overview of the Clark-Wright heuristic, which we use to build initial solutions. Also we give a brief description of Guided Local Search and Tabu Search algorithms. Both meta-heuristics help to improve the initial solution obtained using the local search algorithms, while avoiding falling into local minima. The K-Means and Mean-Shift clustering algorithms are described and used to speed up the calculation of the solution and eliminate unnecessary costs during routes optimization. Finally, to check the quality of the proposed solution, we developed software that implements the described meta-heuristics and clustering algorithms, and provides the routing results in the form of a route graph and its total length. The program was tested on the set of benchmarks of the Belgian roads, which were provided in the work of F. Arnold, M. Gendreau, K. Sorensen K. The results of comparison with the best solutions are provided along with the conclusion on the optimality of the results obtained. That allows us to assert that in less than ten minutes of solving a problem on each of the clusters, the developed software gives results that differ from the best known only by 5-7%. Further work will be aimed at improving the results by exchanging points between neighboring clusters.Рассмотрены методы решения задачи маршрутизации большой размерности. Разработано программное обеспечение для решения представленной задачи при помощи кластеризации множества клиентов и применения метаэвристических алгоритмов.Розглянуто методи розв’язання задачі маршрутизації великої розмірності. Розроблено програмне забезпечення для розв’язання поданої задачі за допомогою кластеризації множини клієнтів та застосування метаевристичних алгоритмів
Інформаційна технологія аналізу динаміки швидкості реакції операторів
Get PDFThe purpose of this work is to develop the information technology for studing the dynamics of adaptive properties of the nervous system of operators. Experimental data are multi-dimensional time series that have been obtained using the reflexometric method of analyzing the reaction time of various psychophysiological types of individuals. For efficient processing of these data, better understanding the structure, finding hidden patterns, trends, some algorithms are proposed, and software (Java programming language) that implements them and provides visualization of the data and the obtained results for convenient analysis is created. The proposed technology allows to determine the similar patterns of the dynamics of reaction rates of various psychophysiological types of individuals, to classify new observation objects to the most relevant psychotype, and to analyze changes of the dynamics in the behavior of each of the investigated operators. The detection of the similarities of the dynamics series, for a more objective assessment, is carried out with the application of a set of similarity measures of different categories: Shape-, Edit-, Structure-, Model- and Compression-based (DTW, LCSS, modified LCSS, TQuest, Euclidean metrics, correlation metrics, trend, seasonality indicators, etc., construction of dendrograms by hierarchical clusterization method). To classify a new object of observation to the most appropriate psychotype, a new method based on a multicriteria comparison with the models is proposed. Analysis of changes in the dynamics of the reaction rate of each of the investigated operators is based on the segmentation algorithm of the multidimensional series on the basis of differential evolution with the previous smoothing of data.The proposed information technology has been tested on the data of the reaction time dynamics of various psychophysiological types of individuals, but can also be applied in the analysis of the similarity in the dynamics of processes of different nature.Разработана информационная технология, которая позволяет определять похожие закономерности динамики реакции различных психофизиологических типов личностей, классифицировать новые объекты наблюдения к наиболее подходящему психотипу, а также анализировать изменения динамики в поведении каждого из исследуемых операторов.Розроблено інформаційну технологію, яка дозволяє визначати схожі закономірності динаміки швидкості реакції різних психофізіологічних типів особистостей, класифікувати нові об’єкти спостереження до найбільш відповідного психотипу, а також аналізувати зміни динаміки в поведінці кожного з досліджуваних операторів
Identification of the components of the time series of hydrological data
Get PDFРассматривается вычислительная схема разложения временного ряда на компоненты и ее реализация на примере данных гидрологического мониторинга.Розглядається обчислювальна схема розкладання часового ряду на компоненти та її реалізація на прикладі даних гідрологічного моніторингу.Conducting research on the hydrological data objects is an important step in monitoring their condition. Changes in the quality and quantity of surface waters has social, environmental and economic consequences and require careful monitoring and, if necessary, quick response to adverse changes. This article discusses the computational scheme for the allocation of components in the time series, as well as the implementation and analysis of the above scheme using the example of hydrological monitoring data.The developed computational scheme processes the data presented in the form of time series.The first step in the analysis of hydrological data is the determination of the primary statistical characteristics of the object under study. Among these characteristics: average, minimum and maximum values of the time series; median, variance, coefficient of variation, kurtosis and asymmetry of the time series. The preliminary assumptions about the presence of deterministic components in the time series are made on the basis of a correlogram analysis based on the initial data.To test the hypothesis of the presence in the time series of the trend component, the Fosters-Stewarts method is used. When confirming the hypothesis that a trend in the time series is present, the trend component is removed by the described linear regression model, the parameters of which are calculated by the least squares method. Identification of periodic component of a time series is carried out using the methods of the Fourier analysis. The dynamics of the series are determined with using the methods of linear and nonlinear regression, in particular: polynomial (3 degrees), power, exponential, Phillips curve and Engel curve, whose parameters are calculated by the least squares method; modified exponential, the parameters of which are calculated by the method of three points. The analysis of the adequacy of the regression models is checked using the coefficient of determination and the adjusted coefficient of determination, also as the average approximation error. The Akaike information criterion and Bayesian information criterion Schwartz are used to determine the best model. The results of the study are accompanied by appropriate graphs and tables
Дослідження життєвого циклу комп’ютерних вірусів
Get PDFThis article is devoted to the research of the dynamics of the spread of computer viruses in the network. The model, which is considered in the article, is based on the SIR model, which was proposed by Kermack W. and O. McKendrick A.G. In accordance with this model, individuals are divided into three groups: susceptible, infected, and cured. Individuals move from the first group to the second, and from the second to the third. The total number of individuals remains constant over time. The changes in individuals in groups are described by a system of three differential equations. In the equations, there are coefficients that are associated with the rate of infection and the rate of treatment. The total rate of change in the number of individuals in the three groups is zero. In this article, a modification of the SIR model was made. In each equation was introduced deviating argument. The deviating argument mathematically expresses the impact of the aftereffect of the processes of infection and treatment. The impact of deviating argument on the dynamics of the spread of computer viruses in the network is considered in the work. Systems of three and of two equations are considered for different values of the deviating argument. The initial problems for these systems with the help of analytical methods are reduced to Cauchy problems, which are solved by numerical methods using a fourth-order Runge-Kutta algorithm. The results are presented in the form of graphs that express the dependence of the number of computers on time. The article analyzes the results obtained and makes conclusions. These studies are new and relevant now and can be used in subsequent studies of computer viruses. The model can be modified and improved. The article may be of interest to specialists who are engaged in research in the field of computer technology, as well as mathematicians who are engaged in the construction and research of mathematical models.В работе исследуется динамика жизненного цикла компьютерных вирусов, которая описывается системами с последействием.В работе исследуется динамика жизненного цикла компьютерных вирусов, которая описывается системами с последействиемВ роботі досліджується динаміка життєвого циклу комп’ютерних вірусів, яка описується системами з післядією
Структура інформаційної технології видалення емоційних ознак з мовного сигналу
Get PDFThe goal of the article is to describe the methods and algorithms of information technology for removal of emotional signs from the speech signal which has been proposed by the authors. Methods of extracting and transforming emotional features, as well as methods of classification of speech signals obtained after transformation are described. The task of removing emotions will be considered successful if, after the transformations, the emotion classifier assigns a speech signal to a class of emotionless speech. The scheme for solving the problem consists of the following steps: 1) extracting informative features and establishing the boundaries of conversion; 2) transforming input data informative features; 3) checking the effectiveness of the transformation. The first algorithm used for transformation is the PSOLA (Pitch-Synchronous OverLap and Add) algorithm designed to change the pitch of the main tone by stretching and compressing the signal on the timeline. The PSOLA algorithm can be used to shift the pitch of voice, retaining the formant position, and thus the identity of the vowels. The basic idea is to extend the time on pitch marks, while the shape of the audio wave of the segment does not change. The second method of transformation, the normalization of the dynamic range of the logarithm of energy, reduces the distribution of energy due to different levels of background noise [2]. The input parameter for the energy normalization unit is the frame energy. Energy is replaced by the energy logarithm based on the similarity to the logarithmic perception of sound by the human auditory system, and also due to the stability of the logarithm to the sharp changes in the energy level. To test the effectiveness of the transformation, the task of recognizing emotions in a language requires the building of a classifier. The input data for classifying and recognizing were emotional expressions, each of which was represented by a set of signs: the frequency of the main tone, the energy and the frequency of crossing zero. Global signs of the minimum, the maximum and the average of each of the sets of values are the vector of expressions. For the classification a model of a mixture of normal sections was used. Using the constructed statistical model of the speech signal, the a posteriori probability of belonging of the utterance to the emotionally neutral class was calculated. The output speech signal meets the set criterion of a successful solution of the problem as formal (result of classification) and perceptual signs, which allows to consider the task of removing emotional features solved.Приводится структура и алгоритмы предложенной авторами информационной технологии удаления эмоциональных признаков с речевого сигнала. Описаны методы извлечения и преобразования эмоциональных признаков, а также методы классификации речевых сигналов, полученных после преобразования, по наличию эмоциональных признаков.Наведено структуру та алгоритмів запропонованої авторами інформаційної технології видалення емоційних ознак з мовного сигналу. Описано методи вилучення та перетворення емоційних ознак, а також методи класифікації мовних сигналів, отриманих після перетворення, за наявністю емоційних ознак
Аналіз та можливість модифікації наявних алгоритмів пошуку оптимального шляху на квадратній сітці з використанням методів паралельного програмування
Get PDFThe task about unmanned aerial vehicle optimal path planning between two points on continuous terrain, which has obstacles, was set. Advantages and disadvantages of existing methods of continuous terrain discretization, application of which required for solution the task using computer, were considered. As the most optimal method of continuous terrain discretization the method of square grid was chosen. As selection criteria of the most optimal among existing path planning algorithms on square grid, the alteration angle was accepted. This criteria was suggested because of physical constraints of unmanned aerial vehicle during maneuvers on continuous terrain. According to the chosen criteria, review and analysis of the most widespread path planning algorithms on square grid, which are varieties of А* algorithm, was carrying out, including the short description of the principle of their work and data structures they use. As the most optimal path planning algorithm, which satisfies a given criteria, the LIAN algorithm was chosen. During testing the LIAN implementation in Delphi programming language were discovered disadvantages of this algorithm, and offered possible variants of their solution. Given that proposed and possible further modifications of LIAN will improve qualitative characteristics of founded path, and also will increase its execution time, LIAN algorithm was analyzed on the possibility of its modification using parallel programming methods. Was offer the scheme of work of parallel variant of LIAN algorithm, in which this algorithm will be divided into two parts: parallel part, which will perform integral subtask of the algorithm, and which can be implemented as an instance of one of the parallel threads, and synchronized part, which will be implemented as a main thread. In the context of reliability of software, which will be implement the parallel variant of LIAN algorithm, was determined, to which data structures, which use original LIAN algorithm, can access the synchronized part of new algorithm, and to which can access the parallel part. The specific variants of LIAN algorithm modifications, that use the parallel programming methods, which are planned in the future to implement and research on efficiency and reliability of execution, were offered.Сформирована постановка задачи поиска оптимального пути на непрерывной местности путем её дискретизации с помощью квадратной сетки. Проведен обзор и анализ самых распространенных алгоритмов планирования пути на квадратной сетке, которые представляют собой разновидности алгоритма А*. В качестве алгоритма поиска оптимального пути на квадратной сетке, который учитывает физические ограничения беспилотного летательного аппарата, был выбран алгоритм LIAN. Были обнаружены недостатки алгоритма LIAN и возможные пути их решения, а также предложены варианты его модификации с использованием методов параллельного программирования.Сформована постановка задачі пошуку оптимального шляху на неперервній місцевості шляхом її дискретизації за допомогою квадратної сітки. Проведений огляд та аналіз найпоширеніших алгоритмів планування шляху на квадратній сітці, які є різновидами алгоритму А*. У якості алгоритму пошуку оптимального шляху на квадратній сітці, що враховує фізичні обмеження безпілотного літального апарату, був обраний алгоритм LIAN. Були виявлені недоліки алгоритму LIAN та можливі шляхи їх вирішення, а також запропоновані варіанти його модифікації з використанням методів паралельного програмування
Перешкодостійке кодування повідомлення електронного підпису
Get PDFWork was carried out on the study and selection of radio links, algorithms for the formation and processing of electronic signatures. Functional blocks, which allow the possibility to carry out the transmission of the electronic signature on the radio communication lines are developed. Computational experiments were carried out to determine the characteristics of the electronic signature notification, in which high impedance is achieved.Проведена работа по изучению и выбору радиолиний связи, алгоритмов формирования и обработки электронной подписи. Разработаны функциональные блоки, которые дают возможность осуществлять передачу электронной подписи по радиолиниям связи. Проведены вычислительные эксперименты для определения характеристик сообщения электронной подписи, при которых достигается высокая помехоустойчивость.Проведено роботу з вивчення і обрання радіоліній зв’язку, алгоритмів формування і обробки електронного підпису. Розроблено функціональні блоки, які дають можливість здійснювати передачу електронного підпису по радіолініях зв’язку. Проведено обчислювальні експерименти для визначення характеристик повідомлення електронного підпису, при яких досягається висока перешкодостійкість
Дослідження моделей соціальних мереж
Get PDFThe models of the social news recommendation were created. It was used combination of past user activities and social relations to receive recommendations.Исследованы модели социальной рекомендации новостей, объединяющие прошлую деятельность пользователей и социальные отношения для получения рекомендаций.Досліджено моделі соціальної рекомендації новин, які поєднують у собі минулу діяльність користувачів і соціальні відносини для отримання рекомендацій. Запропоновано можливі шляхи покращення результатів гібридних методів та надано рекомендації щодо специфіки соціальної мережі
Дослідження криптостойкости систем на основі нейронних мереж
No full textРассматрены вопросы использования нейронных сетей для криптографической защиты информации. Исследованы вопросы криптостойкости и основные причины ненадежности криптосистем. Рассмотрены вопросы применения нейрокомпьютерной сети к криптоанализу. Проведен анализ работы нейрокомпьютерной сети на основе разработанного программного обеспечения. The article deals with the use of neural networks for cryptographic protection of information. Questions of cryptostability and the main reasons for the unreliability of cryptosystems are investigated. Questions of application of a neurocomputer network to cryptanalysis are considered. The analysis of the operation of the neurocomputer network is based on the developed software.Розглянуто питання використання нейронних мереж для криптографічного захисту інформації. Досліджено питання крипостійкості та основні причини ненадійності криптосистем. Розглянуто питання застосування нейрокомп’ютерної мережі в криптоаналізі. Проведено аналіз роботи нейрокомп’ютерної мережі на основі розробленого програмного забезпечення