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The study presents a new method for evaluating the reliability of mobile applications using the Corcoran model. This model includes several aspects of reliability, including performance, reliability, availability, scalability, security, usability, and testability. The Corcoran model can be applied to evaluate mobile applications by analysing key reliability metrics. Using the model significantly improves the reliability assessment of applications compared to traditional methods, which are primarily focused on desktop and server configurations. The aim of the study is to offer a more optimised approach to evaluating the reliability of mobile applications. The paper examines the problems faced by mobile app developers. This study represents a new application of the Corcoran model in evaluating the reliability of mobile applications. This model is characterised by an emphasis on the use of quantitative statistics and the ability to provide an accurate estimate of the probability of failure without any inaccuracies, which distinguishes this model from other software reliability models. The paper suggests using a combination of analytical statistical models, data extraction methods such as sequential pattern analysis, and fuzzy set theory to implement the Corcoran model. The application of the methodology is demonstrated by studying software error reports and conducting a comprehensive statistical analysis of them. To improve the results of future research, the paper suggests making more extensive use of the Corcoran model in various mobile applications and environments. It is recommended to change the model to take into account the constantly changing characteristics of mobile applications and their increasing complexity. In addition, it is advisable to conduct additional research to improve the data mining methods used in the model and explore the possibility of integrating artificial intelligence for more advanced software reliability analysis. Applying the Corcoran model to the mobile app development process to evaluate reliability can significantly improve the quality of applications, leading to increased customer satisfaction and trust in mobile apps. This model can serve as a guide for developers and companies to evaluate and improve their applications, driving innovation and continuous improvement in the competitive mobile app sector.

The subject of the manuscript is the algorithms for radar imaging. This research develops imaging methods and algorithms for wideband and ultrawideband active aperture synthesis systems with antenna arrays and stochastic probing signals. The use of antenna arrays makes it possible to obtain radar images without the need to move radar or antenna system in space. The use of wideband and ultra-wideband stochastic probing signals is justified by their narrow autocorrelation functions. This increased the resolution of the obtained images. The main idea of the proposed algorithms is to filter the original wideband signal into several narrowband processes. Furthermore, only the central frequencies of each narrowband signal were processed. This approach allows us to use the classical widespread methods of aperture synthesis for the case of a wideband signal. Usually, they are applicable only for narrowband signals that satisfy the condition of a quasi-monochromatic approximation. This significantly reduces the overall computational complexity of the imaging algorithm, which simplifies its further practical implementation on the existing radioelement base. Because of the simulation, a primary radar image has been obtained and the overall performance of the proposed approach to processing wideband signals has been confirmed. An increase in the quality of the obtained image when using a multiple of frequency ranges is shown. An experimental study of the effect of processing a wideband signal only at its centre frequency instead of the entire frequency band is conducted. During the experiment, the correlation functions of the signals received by two spaced receivers were obtained. As a result, the Van Cittert-Zernike theorem has been experimentally confirmed. It allows signal processing only at its centre frequency instead of the entire frequency band. Simultaneously, the prospect of expanding the bandwidth of the probing signal is indicated. It, in the presence of a wideband element base and devices for high-speed signal processing, will further increase the imaging resolution of a radar system.

The subject of this study is the cyber vulnerability of wind generators, as part of the cyberphysical system of intelligent power supply networks, Smart Grid. Wind generators produce electricity for further distribution in the network between «smart» electricity consumers, which often include autonomous power systems in medical institutions, autonomous power supply of homes, charging stations for cars, etc. Wind generators operate in two aspects: in the physical and information space. Thus, a violation of the security of the information flow of a wind generator can affect the physical performance of electricity generation, and disable equipment. The study aims to identify types of cyber threats in the wind generator network based on the analysis of known attack incidents, analysis of the Smart Grid network structure, network devices, protocols, and control mechanisms of a wind generator. The tasks of the work are: review and analyze known cyberattack incidents; review the classification of cyber threats to wind farms; consider the most common methods of attacks on the cyberphysical system of wind farms; consider ways of intrusions into the information flow of the cyberphysical system wind generator; consider resilience mechanisms of wind generators in case of a cyberattack, consider the directions of further research. The methods are a systematic approach that provides a comprehensive study of the problem, quantitative and qualitative analysis of incidents of cyber attacks on wind generators, and methods of attacks. The following results were obtained: 11 large-scale known incidents of cyber attacks on the cyberphysical systems of the energy sector and smart power supply networks were analyzed, and information flow features and structure of the wind generators were considered. Main communication interfaces of the Smart Grid network were reviewed, control mechanisms for the physical parts of the wind generator system such as automatic voltage regulator, and automatic generation control were observed, vulnerable data transmission protocols, DNP3 in particular, were analyzed, possible consequences in the case of a cyber-intrusion into the network were considered. Conclusions: wind farms, as part of the Smart Grid system, are a convenient target for cyberattacks, as the number of potential ways to interfere with the information flow of the cyberphysical system is growing due to an increase in the number of sensors, communication channels in the network. This is especially important for the further development of wind farm security systems, which at the time, are not able to provide high accuracy of intrusion detection into the information flow.

Представляється формалізований опис процесу планування навчального навантаження науково-педагогічних працівників кафедри на навчальний рік на кафедрі закладу вищої освіти. Актуальність представлення моделі у формалізованому вигляді визначається необхідністю мати єдиний погляд на процеси підготовки потрібних даних, принципи та алгоритми перетворення даних, а також для уніфікації результатів представлення кінцевих результатів. Запропонований формалізований опис розглядається як основа для подальшого створення відповідної автоматизованої системи розрахунку та розподілу навчального навантаження із можливістю автоматизованої генерації та розсилки звітних документів, зокрема семестрового плану та плану навчального навантаження, а також персональних витягів для науково-педагогічних працівників для розділу «Навчальна робота» їх індивідуальних планів. Представлений процес відображає особливості здійснення розподілу та представлення вихідних даних та результатів планування навантаження на певній кафедрі певного закладу вищої освіти України. Для підготовки моделей використано систему підтримки процесів проектування Enterprise Architect, а тому запропонований формалізований опис може бути адаптований до специфіки іншого закладу вищої освіти або його підрозділу. Основу формалізованого опису складає доменна модель. Кожна з суттєвостей доменної моделі представлена набором атрибутів, що дозволяє використовувати кортежі опису при проектуванні бази даних відповідної програмної системи. Визначені етапи планування навчального навантаження у вигляді діаграм бізнеспроцесів BPMN та діаграм діяльності UML. Представлені математичні співвідношення та описи порядку проведення обчислень, які дозволяють отримати задані значення величин на визначених етапах формування плану. Запропоновані результати отримані на основі нормативної бази України у сфері освіти.

Within the maximum likelihood method an optimal algorithm for polarization target selection against the background of interfering signal reflected from the earth’s surface is synthesized. The algorithm contains joint operations of spectral interference rejection and their polarization compensation by means of certain combinations of interchannel subtraction of signals of different polarizations. The physical features of the elements of the polarization scattering matrix are investigated for the technical implementation of the synthesized algorithm.

Using the statistical theory of optimization of radio engineering systems the optimal method of coherent radar imaging of surfaces in airborne synthetic aperture radar with planar antenna arrays is developed. This method summarizes several modes of terrain observation and it is fully consistent with current trends in the development of cognitive radars with the possibilities of radiation pattern restructuring in space and adaptive reception of reflected signals. Possible modifications of the obtained optimal method for the operation of high-precision airborne radars with a wide swath are presented. The idea is to create a theoretical basis and lay the foundations for its practical application in solving a wide range of issues of statistical optimization of methods and algorithms for optimal spatiotemporal signal processing in cognitive radar systems for the formation of both high-precision and global radar images. To implement the idea, the article highlights the concept of statistical optimization of spatio-temporal processing of electromagnetic fields in on-board cognitive radar systems, which will be based on the synthesis and analysis of methods, algorithms and structures of radar devices for coherent imaging, the study of limiting errors in restoring the spatial distribution of the complex scattering coefficient, the synthesis of optimal feedback for receiver and transmitter adaptations in accordance with a priori information about the parameters of the objects of study, the area of observation and the existing sources of interference. Objective is to develop the theory and fundamentals of the technical implementation of airborne radar systems for the formation of high-precision radar images in an extended field of view from aerospace carriers. Tasks. To reach the objective it is necessary to solve following tasks: – formalize mathematical models of spatiotemporal stochastic radio signals and develop likelihood functional for observation equations in which the useful signal, receiver internal noise and interference radiation of anthropogenic objects are random processes; – to synthesize algorithms for optimal processing of spatio-temporal stochastic signals in multi-channel radar systems located on aerospace-based mobile platforms; - in accordance with the synthesized methods, to substantiate the block diagrams of their implementation; – obtain analytical expressions for the potential characteristics of the quality of radar imaging and determine the class of probing signals and space scanning methods necessary to perform various tasks of radar surveillance; ‒ to confirm some of the theoretical results by simulation methods, in which to reveal the features of the technical implementation of aerospace remote sensing radar systems.

The subject of the study is the process of assessing the level of information security risk that is being implemented with the help of the fuzzy logic apparatus. The purpose of this work is to develop a methodology for assessing the degree of information security risk, which would avoid the uncertainty factor, that occurs when some parts of information about the analyzed automated information system are absent. The methodology is based on the use of fuzzy logic and fuzzy sets and implies the introduction of the term sets for each of the system characteristics and the linguistic assessment of the indicators. The tasks to be solved are to analyze existing information security risk assessment methodologies for identifying their strengths and weaknesses. On the basis of the conducted analysis, a new method for assessing the risk of automated information systems information security is proposed. The following results were obtained: the advantages and disadvantages of qualitative and quantitative methodologies for assessing the risk degree of automated systems information security were identified; the main stages of the proposed methodology were described; the degree of information security risk is calculated in comparison to the FAIR methodology. Conclusion: The methodology presented in the article provides an opportunity to translate the obtained results of risk assessment from a mathematical language into a linguistic form that is more comprehensible to the decision-maker. This increases the effectiveness of the management of automated information systems protection mechanisms.

The software development with distributed teams becomes a critical popular nowadays. Not only for the efficiency and effectiveness the distributed teams provide, but also the distributed teams can supply whole-day works with lower costs. Software development is a kind of knowledge-driven industry which depends on the expertise of employees. Although many scholars have long investigated knowledge management as well as distributed software development, the combination that knowledge management in distributed software development is not a enough explored topic in the past decade’s years. In this paper, a review of relevant extant literature on knowledge management in distributed software development is provided. The relationship between two objects and the factors on knowledge sharing are summarized. By analysis of the characteristics and features of knowledge management, the social media-based framework of knowledge management for distributed software development is proposed.

Subject of research is the process of sea-sky line detection, based on color feature. The purpose of this work is to develop the method is based on color feature as well as textural information. It consists of sea sky region extraction and horizon detection, which is more precise and fast no matter in the sceneries created by camera mounted on board or on shore. The tasks to be solved is: to propose the new linear fitting metric in sea-sky line extraction. The following results were obtained. The proposed linear fitting method was studies. The performance of proposed horizon detection method is estimated by comparison to other 3 state-of-art methods based on 13 challenging testing videos under different circumstances. The 3 methods are: the method based on discriminates and eigenvalues of covariance matrices in RGB space (H-DE); the method adopting probability distribution functions of sea and sky region (H-PDF) and the method by multi-scale cross modal linear feature (MSCM). The video sequences can be classified into two categories: the camera mounted on board and with camera mounted on shore horizon. Conclusion. The proposed linear fitting method can rectify the outlier values. The experimental results on a sequence of test videos demonstrate that the proposed sea-sky line detection method has a higher accuracy and it is more robust and efficient than other existed methods.