The number of satellites in low Earth orbits is predicted to grow over 100,000 in the coming years due to the launch of planned satellite constellations which are often called mega-constellations because of their expected size. They are appealing mostly for global communications, Earth and space observation, as well as for global security and defense. Despite their attractiveness, implementation of satellite constellations is connected with many problems. Among these problems are the necessity of advanced inter-satellite links, onboard management, high-duty Earth terminals and gateways, avoidance of collisions with other satellites and debris, etc. Up to now, no system models and infrastructures have been offered for such large fleets of satellites. The paper summarizes the developed Spatial Grasp Model and Technology (SGT) and its high-level Spatial Grasp Language (SGL), and investigates their applicability for management of large satellite constellations. Embedding cooperating SGL interpreters into all satellites allows to convert the whole constellation into an intelligent system capable of solving numerous problems autonomously, reducing communication with complex ground antennas. The paper shows some basic operations on satellite constellations including broadcasting orders to the whole constellation, collecting information from all satellites and emergent restructuring of the whole constellation. Based on the experience with previous SGT versions, the approach based on virus-like coverage of large spaces allows to implement it even within university environments. Recursive scenarios in SGL are much more compact than under other approaches which may be important for reducing load and interference with other space communications. Figs.: 9. Refs.: 19 titles.
Today’s cybersecurity threats necessitate continuous improvement of the national cybersecurity system. A lot of attention is paid to this issue at the state level in many countries, including Ukraine. It is completely justified, since the level of security of information systems used by state and law enforcement agencies, as well as by critical infrastructure objects is essential not only for the stability and reliability of their operation but also and very often for the lives of people. Decrees of the President of Ukraine and Laws of Ukraine define national cybersecurity strategy, essential cybersecurity measures, measures to ensure cybersecurity of critical infrastructure objects and neutralize cybersecurity threats, main tasks of our state in the field of cybersecurity and major subjects which ensure cybersecurity. National system of cybersecurity is based on the centers of detection, management and response to cybersecurity threats. Based on the system approach, there can be built a concept of the national cybersecurity system visualized as a three-level pyramid. This model is based on the concept of the common information space to exchange data on cybersecurity incidents inside the country and internationally. The model also employs such principles as integrity, hierarchy, structuring, multiplicity and consistency. In order to increase efficiency of response to cybersecurity threats at the national level, co-operation of centers is established and exchange of information about detected cybersecurity incidents is made. Considering the fact that confrontation in thecyberspace intensifies and poses real danger to states, there is an urgent need for development and improvement of thecybersecurity system of Ukraine to respond to modern threats. Responsible for cybersecurity state bodies have to continuously update cybersecurity requirements for all objects of critical infrastructure, define the list of such objects and amend it when necessary. Top executives of such objects have to implement a fairly reliable cybersecurity system, taking into account all the requirements. Figs.: 2. Refs.: 19 titles.
The paper examines the application of the ontological approach to the information modeling of the subject area of expert assessment of capabilities in defense planning tasks. Capability identification and assessment models are basic in countries which are NATO members. At the same time, the growth of the dynamics of all processes which is reflected in a sharp increase in the amount of information required for processing is a characteristic feature of the defense management at the present stage. Methodological complexity of the capacity assessment procedure is stipulated by the lack of rules and approaches to balancing quantitative and qualitative characteristics of capabilities provided by policy documents. It complicates the creation of automated decision-making support tools. This study offers an approach to providing analytical support for expert decision-making based on ontological information models which adequately reflect inherent hierarchical and network structures of elements and take into account their mutual influence in a multifactorial environment. Subject area or «the world» in which decision-making processes take place is usually a large system of taxonomies. To create a taxonomy of data in the subject area of capability assessment, some main basic quanta (conceptual units) of the subject area and basic ontologies were determined. Data analysis on the model example «Intelligence» was carried out as well. The frame approach to the description of generalized generic concepts is offered, and the frame model of a group of abilities on a model example is constructed. A scheme of practical implementation of the obtained decisions based on maintenance of interaction between the ontological model and the relational model of a database is offered.Figs.: 9. Refs.: 20 titles.
Despite the efforts of various organizations led by the Business Software Alliance (BSA), a trade association representing some of the world's largest software developers, computer piracy has continued to grow in recent years. In the continuation of research and development of information systems the article considers a software method of the development software protection, designed to preserve the confidentiality of data from unauthorized access. In information technology protection is understood as a set of actions aimed at combating illegal copying and unauthorized access. The given method consists in authorizing the user of a software or an information system via theInternet and allowing the initial activation of the product on the user's computer, as well as user authorization on the server during each activating of the information system or software. Such authorization allows the developer to monitor statistics on the use of the information system, detect cases of license violations, revoke the licenses of dishonest users, as well as flexibly control the licensing policy. This paper proposes a software authorization control protocol which is based on the use of binding to computer hardware and encryption by 128-bit MD5 hashing algorithm. The software implementation is a dynamic library that integrates with the user's software and controls its authorization and functionality, php-scripts of interaction between the dynamic library and MySQL database, php-script for the creation of a web-form of administration, Android application of software authorization administration. The obtained means of software protection in the development of software and information systems is atimely and necessary mechanism for monitoring the authorized use of the software product.Figs.: 6. Refs.: 25 titles.
A new method of forming echelons in the structure of multi-agent functionals of monitoring information systems is investigated in the process of solving the problem of predicting the incidence of COVID-19 in Ukraine. A multi-agent functional is an over-agent echelon-like structure built by a monitoring information system under conditions of a decrease in the information content of observation results. Echelons of this functional are formed from monitoring agents. Each agent has an individual task. To execute it, the agent processes the results of observations, extracts from them information about the patterns of behavior of the object when the external environment changes. The obtained information is contained in a model knowledge base of the agent in the form of a hierarchical combination of models built by the agent-based synthesizer. Each model is a solution to one of the problems of identification, grouping, forecasting, etc. The list of tasks that have to be solved in order to build the model knowledge base of the agent is formed in accordance with the agent-based task based on an array of input data. For the first time, it is proposed to form echelons of multi-agent functionals from the agents that identify the functional dependence of each indicator monitored from other indicators of the input data array. The array of observation results is expanded into several arrays in order to build each monitoring agent according to the«еach one from the others» rule. After that the agents are combined into echelons thus forming the structure of the multi-agent functional. Multi-agent functionals are constructed with the aim of increasing the variety of processes for processing observation results and extracting knowledge about the patterns of behavior of monitoring objects in the case of a decrease in the information content of these observation results. The ability to build agent-based functionals appears in the monitoring information system as a result of the application of the agent-based approach to the implementation of intelligent monitoring information technology. Tabl.: 2. Fig.: 1. Refs.: 19 titles.
The article is devoted to solving the problem of timely and rapid response to emergencies (EM) of a conflict nature in particular to the formation of a situational awareness model. Properly formed situational awareness allows decision makers to get a complete picture of the situation in time and respond to it duly. As a result of the research, there was offered a situational awareness model which takes into account the three-level model of M. Endsley. This model includes levels of perception, understanding and forecasting of the current and developing situation. One of thefeatures of this model is the construction and use of a mental model which is superimposed on thethree-level one. The paper offers a mental model and its main sections. The process of forming situational awareness is considered separately from the decision-making process. Situational awareness is divided into two components: an operational situation (an objective component) and amental model (a subjective component). The operational situation, as well as the actual situational awareness, is considered as a function of time. The characteristics of the input data of the physical and cognitive levels are given in the article. The paper also provides a multilevel model of formation of situational awareness at the resolution of conflict situations of regional and general character. Local (tactical), regional (operational) and general (strategic) levels of emergency response are considered as well. Situational awareness is defined as a function of the combined operational environment and time. A number of innovative information technologies are also presented and analyzed, which, according to experts, will contribute to improving the formation of situational awareness in the coming years. The results of the research can be used to build a decision-making process in situational centers. Figs.: 2. Refs.: 10 titles.
A significant part of the methods and approaches to automatic spelling correction is language-dependent since they are focused on grammatical rules and phonetics of a particular language. The vast majority of works in this field is devoted to texts in English, a smaller part – to other Germanic languages, a very small part – to Slavic languages and the smallest part – to the Ukrainian language. A special toolkit (a simulation model (SM)) and the evaluation results of the corrective properties of some algorithms in relation to the correction of typical typing errors in Ukrainian words, taking into account the preliminary dictionary indexation, are considered in the article.SM has a modular structure and is configurable for specific dictionaries, types of errors and index generation algorithms. For the «dictionary – type of errors – algorithm» combination SM distorts the words of the given dictionary with a mistake and searches for the «closest» words-candidates to correct the wrong word. A general algorithm for processing a word with an error includes pre-selection (PS) of a set of words-candidates according to the rules of the indexing algorithm, and final selection (FS) as a prioritization of the selected words and narrowing the search area for a «correct» word according to the accepted proximity criteria for the word to be corrected, and various selection criteria.A trial simulation was performed for Soundex and Metaphone phonetic algorithms adapted to the Ukrainian language. An ensemble of errors is a set of typing errors which includes four different basic single misspellings (replacements, insertions, omissions and rearrangement of letters), as well as double errors which are a mixture of basic errors. 59.6 million words with errors were processed; the average time for processing one word was 0.07 ms. The simulation results contain the total number of corrected words grouped by the type of error, the number of correct words-candidates offers, the number of incorrect offers, the number of missing offers and the average number of candidates in the offers at the PS and FS stages.Tabl.: 9. Figs.: 4. Refs.: 14 titles.
The article outlines the problem of the lack of verification obtained by students during the study of theoretical foundations in real conditions, in particular the problem of practical implementation of team projects in the field of software development and project management in educational institutions, although in modern IT companies such practice is taken as a basis of their work. The following popular software products used for automated planning and teamwork control in enterprises are analyzed: Basecamp, Jira, Asana, Trello. It is noted that the main task of educational institutions is to recreate for the team the working conditions in companies and immerse students in the most accessible process of creating a team project in order to develop a quality software product. For this purpose the Microsoft Solution Framework methodology was chosen in order to implement the educational team project. The aim of this article is to formalize the process of planning and implementation of a sprint in the form of an algorithm of actions that must be carried out and programmatically recorded in the created educational team project. A scheme of Scrum-team working elements interaction in the Visual Studio software environment is generalized. An algorithm of work of team project members is unified with the aim of realization of all opportunities offered by Microsoft on the basis of Team Foundation Server work. The article describes an algorithm of the sprint implementation stage according to the flexible Scrum methodology. It contains a detailed description of the work performed on each sprint, i.e. every stage of the teamwork, and provides direct performance of tasks by each team member. To cover the results of the work, a Daily Meeting is held, and at the end of the sprint an increment of the software product is obtained.Figs.: 2. Refs.: 15 titles.
QUALITY, RELIABILITY AND CERTIFICATION OF COMPUTER TECHNIQUE AND SOFTWARE
Microprocessor systems, which are designed for long-term continuous operation in a standalone mode, must provide a minimum downtime during their exploitation. The impact of electrostatic discharges on a microprocessor system can cause its damage. Damage to the system is the cause of its malfunction that can be either a self-resolving failure or a failure which is eliminated by minor operator intervention. This failure can lead to a hang of the microprocessor system which increases the system downtime and reduces the efficiency of its usage. According to the results of the study of the behavior of systems under failure both in laboratory conditions and directly at enterprises, a basic electrical circuit and an algorithm for the operation of anexternal watchdog timer relative to the microprocessor have been developed which allows to restore the microprocessor of autonomous systems after its exposure to electrostatic discharges that do not exceed the destruction threshold by restarting it by power in the automatic mode. The hardware and software implementation of the developed method for increasing the fault tolerance to the effects of electrostatic discharges is presented and put into operation. Efficiency of this technical solution is confirmed by the results of the exploitation during a few years of several hundred microprocessor systems at various Ukrainian enterprises for military, industrial, residential and municipal purposes. The solution of this problem had been performed by the author of this article at the level of absolute world novelty what is confirmed by a patent.Figs.: 3. Refs.: 17 titles.
Diesel locomotives of the ČKD ČME3 class are the basis of the fleet of shunting locomotives of Ukraine. Today, the average service life of these machines is 35–38 years, while the established standard is 25 years. Accordingly, if the operation is too long, there arise some problems which are associated not only with equipment failures, but also with failures of the supporting structures of the corresponding machines. The main failures caused by metal fatigue are the occurrence of cracks along the contour of the vertical sheet of the bogie frame along the welded joints and the occurrence of cracks in the area of fastening of the traction motor brackets. Determination of such damages requires significant costs and downtime of therolling stock, because quality control of the objective condition and suitability is possible only when lifting the locomotive body, disconnecting the bogies and completely cleaning them from dirt. Now such control is carried out every 3 years, regardless of the circumstances. In this regard, the probabilistic approach to assessing the state of supporting structures and predicting both the period of condition monitoring and the service life have its advantages. It requires much lower costs and can be used to obtain recommendations for the selection of samples specifically for timely control, including the probability of failure, which is based on taking into account various kinds of indicators. The article proposes to use the Bayesian method which has found wide application in the theory of reliability. It has been demonstrated that it allows one to take into account the probabilistic characteristics of processes and operating conditions, on the basis of which it is possible tojudge the reliability of load-bearing structures of diesel locomotives most reliably. Applying the Bayesian method together with the probabilistic-physical one, which uses a diffusion-monotonic distribution, it becomes possible to calculate the average operating time before failure and predict the time of safe operation of the equipment under study. Таbl.: 2. Refs.: 5 titles.
This article analyzes modern trends of the development of the theory and practice of dependability of computer and other systems. The use of dependable computer systems and the development of methods for dependability indicators calculation are discussed at specialized national and international forums and conferences in many countries around the world. It is still relevant to define, clarify and formulate the basic concepts and taxonomy of the dependability theory. All over the world intensive scientific research, practical scientific and technical development of computer systems and networks are carried out with the aim of ensuring dependability in aviation, rocket, space and military-industrial complexes, control systems at nuclear power plants, railway transport, healthcare systems and also in the financial sphere of business-critical application. Dependability theory is relevant, but still underdeveloped in the following areas: cybersecurity systems, network traffic anomalies detection, computer-aided design systems, augmented and virtual reality systems, self-healing systems, robotics, cyber-physical sensor systems, methods and means of human identification (biometrics), environmental monitoring, large-scale data analytics and data mining for business areas and digital banking, databases, healthcare computer systems, wireless communication systems. The following areas are still gaining relevance towards improving their dependability level: cloud storage and computing, encryption, quantum computing and cryptographic methods, maintaining confidentiality and personal data access control, blockchain security and reliability. The results obtained in the paper can be useful for a wide range of experts that are involved in the research of dependability in all areas of its application.Refs.: 11 titles.
