Scattering characteristics of surface ships with complex shape

Based on the previously developed by the authors method for estimating the scattering characteristics of objects located near the interface between two half-spaces, the scattering data of a large Project 775 landing ship (NATO codification: Ropucha) are obtained. A surface model of the ship under study and the results of calculations of its scattering characteristics are given. Scattering characteristics were obtained for different probing conditions. The radar cross-section circular diagrams, mean and median radar cross-section values, averaged in different azimuth aspect ranges of probing for the object under study are presented.

An information technique for segmentation of military assets in conditions of uncertainty of initial data

To solve the applied task of detecting military assets in aerospace images the presented paper investigates the processes of constructing segmented maps of the images. The goal is to develop an information technique for detecting military assets in conditions of uncertainty of initial data. To achieve the goal, the following tasks were formulated: 1) to analyze usability of the existing segmentation methods for automatic detection of military assets in the images; 2) if the existing methods are inapplicable, to develop a new algorithm to solve the problem. In the paper the following methods are used: the methods of digital image processing, the methods of Boolean algebra and fuzzy sets, the methods of statistical analysis. The following results are received. Analysis of the known segmentation methods showed that due to camouflage coloring of the military assets, similarity of their color characteristics to those of underlying surfaces and due to the presence of large number of textured fragments in the images those methods provide segmented maps of poor quality. Among the common problems arising when conventional methods are used there are wrong segmentation, when the received contours do not coincide with the borders of the objects of interest; oversegmentation, when there are a lot of minor segments which produce "litter" objects; undersegmentation, when potentially possible segments are missed etc. As the conventional methods are inapplicable, in the paper it is suggested using the fuzzy logic systems. For each pixel the probability of the fact that the pixel belongs to the object or to the background is calculated. For making decision whether a pixel belongs to the object the production rules based on the chosen most significant factors (probabilistic values of spectral sub-bands, belonging of the neighboring pixels to the object, jumps of brightness in spectral sub-bands on the object's borders) are constructed. Conclusion. The suggested technique ensures high-quality definition of objects' borders, thus considerably increasing the reliability of military assets recognition.

Метод фільтрації мультиплікативного шуму на зображеннях з використанням технології сурогатних даних

У статті розглядається метод фільтрації мультиплікативного шуму на цифровому зображенні, заснований на представленні гомоморфного образу зображення в векторно-матричному фазовому просторі і використанні нетрадиційних методів багатомірного статистичного аналізу, а саме – технології сурогатних даних, яка дозволяє з єдиного зображення, спотвореного мультиплікативним шумом, формувати псевдоансамбль “сурогатних” зображень із подальшим їхнім усередненням. Проведено імітаційне моделювання запропонованого методу фільтрації шуму. Проведений візуальний порівняльний аналіз просторової і радіометричної роздільної здатності запропонованого й деяких відомих методів фільтрації шуму та їх чисельних мір якості. Показано, що запропонований метод демонструє кращу просторову та радіометричну роздільну здатність у порівнянні з найпоширенішими методами фільтрації шуму.

The ways to organize of distance learning in higher military educational institutions of Ukraine and the world during overcome of the coronavirus infection pandemic Covid-19

The global informatization of modern society, development of telecommunication, communicular and information technologies - on the one hand and the powerful challenges to all humanity in the form of epidemics (coronavirus infection COVID-19, bird flu, various forms of pneumatic and hepatitis), natural and man-made disasters, military and political conflicts, wars - from the second, determine significant changes in priority forms of educational process, and distance learning (DL), in these conditions, becomes the only possible option for providing quality educational services with minimal financial expenses for its organization.

Estimation of noise radiance point sources multichannel direction finding systems resolution by linear prediction method

The resolution of multichannel direction finding systems of independent noise radiance point sources is estimated quantitatively under a limited learning sample on the basis of a linear prediction methods “bank” and modified Capon algorithms.

Development of Niederriter crypto-code design models on LDPC-codes

The development of mobile technologies and computing resources has expanded the range of digital services and practically outstripped the development of computer technologies. This approach ensures the use of mobile and wireless networks in almost all areas of smart technologies, provides a further synthesis of cyberspace and the mobile Internet. However, the absence of security service protocols: confidentiality and integrity, initially when they are formed in the structure of LTE technologies, provides cyber attackers with the opportunity to use mobile Internet channels to implement targeted (APT) attacks. The development and emergence of a full-scale quantum computer with Shor and Grover algorithms can lead to a sharp decrease in the level of security of cryptosystems based on symmetric and asymmetric cryptography (including cryptography on elliptic curves). In addition, modern cyber threats have signs of synergy and hybridity, and their integration with social engineering methods practically does not allow providing the required level of preventive measures (protection). The article proposes post-quantum cryptosystems based on the Niederreiter crypto-code construction on low-density parity-check codes (LDPC-codes). This approach makes it easy to integrate into wireless networks based on IEEE 802.16 and IEEE 802.15.4 standards, as well as LTE mobile technologies. At the same time, the required level of resistance to modern threats ensured.

Method of description for the dynamics of the signal delay change in discrete time with changing aircraft position in space

The article presents an innovative approach to the description of the aircraft range parameter in discrete time when simulating the process of its repositioning in space. A method of describing the dynamics of changes in signal delay in discrete time when the aircraft is changing its spatial position is proposed. Such a model adequately describes the change in signal delay in discrete time. The direction of estimation for the adequacy of radio signal delay change simulation in algorithms of optimum filtration is defined in accordance with the aerodynamic properties of the aircraft. Simulation of the signal delay dynamic change is carried out (it is completely described by the dynamics of change in the distance to the aircraft). The transformation stages of simulation data for the initial model in continuous time with realization of the standard Gaussian random numbers are justified. Information on the simulation data transformation taking into account the correlation matrix of discrete white noise is provided. A method of calculating the transition matrix through the Laplace transform is proposed. The scientific-applied direction of research is determined – it lies in the development of a method for the legitimate representation for the mathematical model of aircraft’s changing range in discrete time within one-dimensional space: the longitudinal and the transverse dimensions. This approach takes into account the continuous description for a system of stochastic differential equations. A comprehensive algorithm for modeling the values of discrete white noise on modern computer equipment and calculating the dynamics of the aircraft range parameter changes is proposed. This algorithm allows to correctly form the a priori information about the change of the vector parameters of the aircraft spatial position at discrete moments of time. As a result, it was shown that the use of the obtained information in the optimal filtering algorithms minimizes the error when determining distance to the aircraft and, accordingly, allows to increase the accuracy and adequacy of the signal delay simulation in discrete time. The results of this research can be used in modernization of the existing models and development of promising on-board radar stations, integrated rangefinders, systems of radio technical reconnaissance and electronic warfare systems, as well as in technical implementation of aircraft flight simulation systems.

Багатокритеріальна (векторна) оптимізація портфеля валют при нестохастично невизначеному зовнішньому економічному середовищі

На основі аналізу літератури встановлено, що невизначеності різної природи, які властиві операціям по конвертації валют з урахуванням чинника часу, вимагають використовувати хеджування валютних ризиків. Встановлено, що серед моделей хеджування ризиків одна з найбільш поширених моделей – модель Марковіца. В роботі розглянуто її використання за результатами можливих значень курсу валют у майбутньому. Для розв’язання задачі у майбутньому часі запропоновано використання інтервальних чисел, представлених в системі ЦЕНТР-РАДІУС. В роботі запропоновано наступні методики: визначення основних статистичних характеристик зміни курсів валют, включених до складу портфелю; визначення статистичного зв'язку між окремими валютами, включеними до складу портфелю; визначення статистичних властивостей часового ряду даних про зміну курсу валют. Сформульована задачу Марковіца як задачу багатокритеріальної (векторної) оптимізації портфеля валют при нестохастично невизначеному зовнішньому економічному середовищі. Розв’язання такої задачі (структура портфелю валют) одночасно дає можливість максимізувати прибуток і одночасно мінімізувати ризик операцій, пов’язаних з конверсією валют. Для розв’язання задачі використано згортку критеріїв, яка забезпечує зменшення відносних значень цільових функцій від їх оптимальних значень рівномірно.

Development of a protocol for a closed mobile internet channel based on post-quantum algorithms

The development of computing technologies has made it possible not only to expand the range of mobile communication services, but also to significantly increase computing capabilities. The emergence of mobile Internet, 4G, 5G technologies makes it possible to talk about a fundamentally different approach to ensuring the quality of service to network customers, creating fundamentally new approaches to ensuring the efficiency and reliability of transmitted information flows. However, such a rapid growth of GSM technologies without the introduction of security services leads to active actions of attackers and cyber terrorists, the emergence of new and modification of known threats. Mobile communication channels are used by cybercriminals for selfish purposes of access to database resources not only of the mobile Internet, but also to the databases of information and communication systems and networks. The article proposes a fundamentally new approach to ensuring the closure of the voice channel of the mobile Internet based on post-quantum cryptography algorithms – McEliece and Niederreiter crypto-code constructions on elliptic codes. This approach provides not only the offline mode of closing the voice channel and creating a VPN channel in tunnel mode, but also the required level of cryptographic strength in the face of the emergence of full-scale quantum computers.

Science & technology trends in cognitive radar concept

Currently, human operators provide cognition in a radar system. However, advances in the “digitization” of radar front-ends, including digital arbitrary waveform generators (AWG) and advanced high performance embedded computing (HPEC) make it possible to vary all key radar parameters (power, pulse length, number of pulses, pulse repetition frequency (PRF), modulation, frequency, polarization) on a pulse-by-pulse basis within ns or ms and over a wide operating range. This timescale is much faster than the decision-making ability of a human operator. The cognitive-inspired techniques in radar, that are intensively developing last years, mimic elements of human cognition and the use of external knowledge to use the available system resources in an optimal way for the current goal and environment. Radar systems based on the perception-action cycle of cognition that senses the environment, learns relevant information from it about the target and the background and then adapts the radar to optimally satisfy the needs of the mission according to a desired goal are called cognitive radars. In the article, recent ideas and applications of cognitive radars were analyzed.