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The paper analyses the existing methods and best international practices for creating a system of professional standardisation in the field of cybersecurity and information protection. It is shown that at present, a new List of professions has been formed in accordance with the needs of the labour market in the field of cybersecurity and information protection. For the first time in many years, on the initiative of a comprehensive group of specialists at the State Special Communications Service of Ukraine, changes were made and new professions were added to the classifier of professions DK - 003: 2010 in the field of cybersecurity and information protection (Amendments #10, Order of the Ministry of Economy No. 810 dated 25.10.21; Amendments #11, Order of the Ministry of Economy No. 5573 dated 29.12.22). According to the Amendments for 2024, the total number of cybersecurity professions in Ukraine is 27 professions and 46 qualifications. According to the "Classifier of Occupations" DK 003:2010 and in accordance with the best international practices, the said list of occupations was formed on the basis of the implementation of the best international professional standards, namely, taking into account the European Cybersecurity Skills Framework (ECSF ENISA, ECSF role profile). Also, the paper provides conceptual and methodological recommendations for the formation of a basic model of the content of professional standards, namely, the creation of the content of competencies, knowledge, skills and abilities of the professional standard "Head of a structural unit for information security and cyber defence". The material presented is considered with the aim of analysing and providing practical recommendations on methods and procedures for the implementation and development (adaptation to national requirements) of professional standards (hereinafter referred to as PS) and their corresponding qualifications in accordance with the approved Amendments to the National Classifier of Occupations "Classifier of Occupations" DK 003:2010 (Amendments No. 10, Order of the Ministry of Economy No. 810 of 25.10.2021; Amendments No. 11, Order of the Ministry of Economy No. 5573 of 29.12.2022). This material presents an example in accordance with the European Cybersecurity Skills Framework (ECSF) and in accordance with the Classifier of Occupations DK 003:2010 and the National Qualifications Framework of Ukraine. [ABSTRACT FROM AUTHOR]

This paper explores the relevance of protecting information systems from ransomware in the context of the rapid development of cybercrime, especially in the context of the war in Ukraine. The article focuses on the shortcomings of traditional anti-virus solutions and the need to introduce new technological solutions for effective monitoring of network traffic. One of the proposed solutions is the use of an enhanced Berkeley Packet Filter (eBPF), which allows detecting potentially malicious activity without interfering with the operating system kernel. The importance of solving this problem cannot be overestimated, given the severe consequences of ransomware attacks, which can range from the loss of important data to complete paralysis of the enterprise infrastructure. It is also noted that the eBPF can play an important role in developing mechanisms for detecting, analyzing and countering cyber threats, which is significant for both theoretical research and practical application in the field of cybersecurity. The rest of the article reveals the issues of using eBPF to monitor the activities of ransomware and detect it in network traffic. A comprehensive approach to evaluating machine learning algorithms that can be used to analyze data collected by eBPF is proposed, with an emphasis on the support vector machine (SVM) algorithm as the most suitable for detecting ransomware. The paper also evaluates the effectiveness of SVM in comparison to other tools, which emphasizes its advantages for cybersecurity tasks. The article concludes with a discussion of the possibilities of implementing eBPF in the practical field of cybersecurity, in particular, its impact on improving the efficiency of security systems, reducing incident response times, and ensuring more dynamic and flexible security management. The authors emphasize that solving this problem iis of significant importance for the scientific community and practical application, suggesting new directions for further research in the field of cybersecurity. [ABSTRACT FROM AUTHOR]

The paper searches the work process of a ship agent - providing a set of representation services and ensuring compliance with the interests of a vessel located in a sea port for the purpose of loading/discharging of cargo and/or for other purposes. Agents organize and coordinate the arrival, staying and departure of vessels from the seaport. In the paper, the agency service of ships in sea ports is presented as one consisting of three stages of the work of a ship agent - operations that are carried out before the arrival of the vessel in the port, during the stay of the vessel in the port and after her departure. The events that fixed the beginning and end of each stage are defined. The agency service process is rather complex due to the large number of third parties to be involved in the procedures and formalities that allow a vessel to arrive in the port and depart. Such a process is accompanied by the issuing of a number of documents that the agent must fill in in order to inform all interested parties. The main time of the vessels' stay in the port are cargo handling - loading and discharging operations. During this period, agency service includes non-stop control of cargo handling, considering the interests of the shipowner. The three stages of the process under consideration are formalized in their mutual dependence and mutual conditioning using the apparatus of temporal logic. Their clear coordination in time ensures the coordination of the process in general, because only the timeliness and correctness of each stage of the agency service process and its completion allow the next stage to begin. The presented process was formalized with the help of temporal logic operators, which can establish cause-and-effect relationships between the stages and ensure the continuity of the process and the interconnection of the stages themselves. A set of documents necessary for the start, execution and completion of each of the stages has been defined. Some of the documents are external to the ship agent, some are issued directly by him, but each of them is key in the implementation of certain operations in the process of agency service. [ABSTRACT FROM AUTHOR]

The paper presents the results of determining the amplitude-frequency characteristic of the Z14XEP engine vibration of the Opel Astra G (F69) at idle speed depending on the steering wheel position. The opposite of changes in the values of the amplitude and frequency of mechanical vibrations of the engine on its supports was determined: an increase in amplitude and a decrease in frequency under the condition of the beginning of the movement of the hydraulic fluid through the power cylinder of the hydraulic booster. The actuation of the hydraulic boost system with an electric pump drive generally causes an increase in the amplitude of engine oscillations by 24.2% in the longitudinal and vertical planes, which occurred before the fluid was replaced, and by 14.4% after its replacement. It was determined that, regardless of the state of the hydraulic fluid at the beginning of its circulation through the cavities of the amplifier's power cylinder, the frequency of mechanical vibrations of the engine decreases in the longitudinal and vertical planes by 25%. In the transverse plane, the oscillation frequency is reduced by 35%, except when the hydraulic fluid is changed, when the oscillation frequency remains unchanged. It has been established that the quality of the hydraulic fluid of the power steering system significantly affects the change in mechanical vibrations of the engine only when the steering wheel is deviated from the neutral position. It was determined that a decrease in the viscosity of the new hydraulic fluid by 8.3% compared to the fluid that was replaced causes changes only in the amplitude of engine oscillations. In the longitudinal plane, the oscillation amplitude decreases by 13.3%, in the vertical plane - by 15.1%, and in the transverse plane, the oscillation increases by 25.4%. Reducing the viscosity of the hydraulic fluid used reduced the resistance to its movement through the holes, channels and pipelines of the power steering system and reduced the power take-off to drive the power steering pump. [ABSTRACT FROM AUTHOR]

The paper examines the process of increasing the functional properties of coatings made from powders of self-fluxing alloys by using the method of electric contact sintering. It has been shown that the adhesive strength of the coatings is high. with the base is ensured by the formation of a wide diffusion zone on the side of the base. There is no liquid phase at the coating-part boundary. This indicates that, unlike surfacing, during electrical contact sintering there is no overheating and no mixing zone of the coating material with the metal of the part. X-ray study of the phase composition of coatings shows that under optimal conditions of electric contact sintering, the carbides present in the original powder are mainly retained in the sintered layer, which indicates the preservation of the hereditary properties of the coating material during electric contact sintering. The effect of grinding the carbide phase makes it possible to obtain sintered layers with evenly distributed carbide inclusions, which helps to increase the wear resistance of coatings. Carbide particles have a specific acute-angled shape, which indicates the preservation of the original properties and structure of the coating material during electrical contact sintering. Impulse temperature-force influence in the process of coating formation during electric contact cauterization leads to the dispersion of solid phase particles, which helps to increase the microhardness and wear resistance of the obtained coatings by 2-3 times. The developed technology for obtaining coatings from self-fluxing alloy powders by electric contact sintering leads to a decrease in the cost of manufacturing and restoration of parts due to the replacement of alloy steel with low-carbon steel with coatings from SFP SFS while increasing the resource of parts by 3-5 times. [ABSTRACT FROM AUTHOR]

This paper explores the relevance of protecting information systems from ransomware in the context of the rapid development of cybercrime, especially in the context of the war in Ukraine. The article focuses on the shortcomings of traditional anti-virus solutions and the need to introduce new technological solutions for effective monitoring of network traffic. One of the proposed solutions is the use of an enhanced Berkeley Packet Filter (eBPF), which allows detecting potentially malicious activity without interfering with the operating system kernel. The importance of solving this problem cannot be overestimated, given the severe consequences of ransomware attacks, which can range from the loss of important data to complete paralysis of the enterprise infrastructure. It is also noted that the eBPF can play an important role in developing mechanisms for detecting, analyzing and countering cyber threats, which is significant for both theoretical research and practical application in the field of cybersecurity. The rest of the article reveals the issues of using eBPF to monitor the activities of ransomware and detect it in network traffic. A comprehensive approach to evaluating machine learning algorithms that can be used to analyze data collected by eBPF is proposed, with an emphasis on the support vector machine (SVM) algorithm as the most suitable for detecting ransomware. The paper also evaluates the effectiveness of SVM in comparison to other tools, which emphasizes its advantages for cybersecurity tasks. The article concludes with a discussion of the possibilities of implementing eBPF in the practical field of cybersecurity, in particular, its impact on improving the efficiency of security systems, reducing incident response times, and ensuring more dynamic and flexible security management. The authors emphasize that solving this problem iis of significant importance for the scientific community and practical application, suggesting new directions for further research in the field of cybersecurity. [ABSTRACT FROM AUTHOR]

The growth of mobile technologies and computing power has significantly expanded the range of digital services and actually outpaced the development of computer technology. This promotes the use of mobile and wireless networks in most areas of smart technologies and supports the further combination of cyberspace with the mobile Internet. However, the lack of security protocols that ensure the confidentiality and integrity of data in the early stages of LTE technology implementation creates conditions for cybercriminals to use mobile Internet channels to conduct APT attacks. With the development and appearance of a full-fledged quantum computer that uses the Shor and Grover algorithms, a significant decrease in the stability of cryptosystems built on the basis of symmetric and asymmetric cryptography, including cryptography on elliptic curves, is possible. In addition, modern cyber threats show signs of synergy and hybridity, and their combination with social engineering methods makes it difficult to implement effective preventive measures. The paper proposes post-quantum cryptosystems based on the McAleese crypto-code scheme, which uses low density parity check codes (LDPC codes). This approach allows for easy integration into wireless networks that comply with IEEE 802.16 and IEEE 802.15.4 standards, as well as LTE technologies, providing an adequate level of protection against modern threats. [ABSTRACT FROM AUTHOR]

Data protection is a critical aspect of today's information environment, as the number of threats, both from attackers and as a result of human error, is constantly increasing, putting the confidentiality and integrity of information at risk. Basic data protection principles include access control, encryption, backup and activity monitoring. A multi-level approach to security, including physical, administrative and technical measures, reduces the risks of unauthorized access and data loss. The article examines the importance of password security in today's digital environment. Given the growing number of cyber threats, maintaining privacy and protecting personal data has become a priority. One of the effective password management tools is KeePass, a password storage program that provides a high level of encryption and security. This paper analyzes the key features of KeePass, its advantages and disadvantages compared to other password managers. The article also draws attention to the need to choose a reliable password manager to ensure multi-level protection of user data. The use of such tools becomes especially relevant in the context of the growing number of cyber-attacks and the need to preserve confidentiality in various industries, including business and government institutions. [ABSTRACT FROM AUTHOR]

In technical systems, in addition to mechanical oscillations, it is also worth noting electrical sinusoidal processes in alternating current circuits, in electronic devices, in particular, in the industrial power supply network, oscillatory circuits, signal generators, communication systems, etc. In radar systems, sinusoidal signals with frequency drift can also be observed, for example, linear frequency-modulated or Doppler signal reflected from a maneuvering target, the speed of which has at least one derivative. Among the possible ones, in the future we limit ourselves to comparative studies of two types of SL-oscillations - harmonic (SG) with all constant parameters and sinusoid with linear frequency drift (SD). At the same time, we will consider two types of their mathematical models - trigonometric (T-models) and autoregressive (AR-models). The paper analyzes sine-like trigonometric models and features of their application. The peculiarities of the task of measuring the parameters of the movement of an object with uniform acceleration based on the estimation of the Doppler frequency of the radar probing signal reflected from it are considered. A synthesis of simplified and approximate ARD models was carried out. An important feature of the synthesized ARG model is the fact that only one parameter of the trigonometric model appears in it - the normalized frequency. The main merit of the synthesized simplified and approximate ARD models is their invariance to the amplitude and initial phase of the sinusoidal signal. This reduces the parametric dimension of the estimation problem from four to two parameters, which contributes to a significant improvement in the speed of calculations. Based on mathematical modeling, statistical errors were obtained for different sampling intervals in the triplet and sample size. Based on mathematical modeling, statistical errors were obtained for different sampling intervals in the triplet and sample size. The selection of pairs of triplets was probabilistic. Calculations show that the error of the obtained model does not exceed 8%. [ABSTRACT FROM AUTHOR]

The paper presents a comparative analysis of the designs of non-contact rotational drives on gas-lubricated bearings used in machines and mechanisms for various purposes, such as microturbine generators, two-axis displacement tables, pneumatic spindles, and single-crystal cutting machines. The technical and technological advantages of non-contact direct rotational drives with gas-lubricated bearings are shown; the use of a non-contact drive with an aerostatic bearing in precision positioning mechanisms results in a uniform (smooth) movement with maximum positioning accuracy of the actuator. The approaches to designing the drive as a single and adjustable dynamic system, the characteristics of which are established and adjusted by changing the design, technological parameters, and adjusting the aerostatic supports, are considered. Based on the research, the directions of technical improvement of drives on gasstatic supports which allow to maximize the existing advantages and features of gas-lubricated supports are outlined. [ABSTRACT FROM AUTHOR]

The paper is devoted to the study of the physicochemical properties of aviation biofuels, in particular, to the substantiation of the influence of bio-additives based on various vegetable oils on the properties of jet fuels and to the assessment of the possibility of using new bio-additives to produce aviation biofuels. The aviation industry’s current state is considered and its development’s key directions are presented. Considering the tasks of minimizing the environmental impact of aviation, decarbonizing the aviation sector and increasing its energy efficiency, one of the industry’s main priorities is the development of technologies for the production of alternative aviation fuels and their practical use. This paper considers alternative aviation fuels (biofuels), which are a mixture of traditional aviation fuels and bio-additives derived from various vegetable oils. Taking into account the trends of active transition from first-generation biofuels to second- and third-generation biofuels, the article considers new types of plant raw materials for obtaining bio-additives to fuels. In particular, the possibilities of using bio-additives based on palm kernel and coconut oils to produce second-generation biofuels are considered. The chemical composition and physicochemical properties of bio-additives based on various vegetable oils were investigated and analyzed. It is shown that the quantitative and qualitative composition of bio-additives determines their physicochemical properties. Further, the physicochemical properties of aviation biofuel samples based on petroleum aviation fuel and bio-additives were investigated. It is shown that the introduction of bio-additives into the composition of petroleum aviation fuels leads to changes in their properties, in particular, to an increase in density, viscosity, and crystallization temperature. The experimental results substantiate that bio-additives based on palm kernel and coconut oils have better characteristics than the previously studied bio-additives (based on rapeseed and castor oils), in particular, regarding the possibility of their use as components of aviation biofuels. Thus, the new bio-additives can be successfully used for further research on the development of alternative aviation fuels. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental studies of the wear process of detonation coatings and counterbodies and compares them with other types of coatings, obtaining wear characteristics. The characteristics of wear of coatings are described in an analytical form, as well as the results of the study of tribological structures. The tribotechnical characteristics of detonation coatings are determined, taking into account the properties of dissipative structures that are self-formed in contact with friction. The effectiveness of the method of researching the process of wear of detonation coatings has been determined. It has been established that when coatings are rubbed against chrome, the total wear of the friction pair is significantly less than when rubbed against bronze. This is due to the best tribotechnical properties of chromium in the experimental field. The coefficient of friction of electrochemical chromium coatings is of the same order as when rubbing on bronze. The total intensity of wear of the coating and the counterbody when rubbing against chrome is somewhat lower than when rubbing against bronze. Since tribological structures are formed from complex oxides, asphaltenes, cokes, etc. during friction of coatings on chrome alloy VT-22, therefore the tribotechnical characteristics of such systems are somewhat lower than in systems that include bronze. [ABSTRACT FROM AUTHOR]

The main purpose of evolutionary optimization is to find a combination of parameters (independent variables) that would help maximize or minimize the qualitative, quantitative, and probabilistic characteristics of the problem. Recently, integrated optimization methods have become very common, borrowing the basic principles of their work from wildlife. Researchers are experimenting with different types of representations, for example, evolutionary and genetic algorithms use selection methods and genetic operators. A large number of algorithms based on the swarm method are known. The artificial bee colony is an optimization method that mimics the behavior of bees, a specific application of cluster intelligence, the main feature of which is that it does not need to understand specific information about the problem, you just need to optimize the problem. Comparing inferiority with the help of the local optimization behavior of each person with an artificial bee finally leads to the appearance in the group of a global optimal value with a higher rate of convergence. The paper considers the method of solving the optimization problem based on modeling the behavior of the bee colony. Description of the model of the behavior of intelligence agents and forage agents, search mechanisms, and selection of positions in a given neighborhood. The general structure of the optimization process is given. Graphical results are also presented, which prove the possibility of the bee colony method to optimize the results, i.e. from all multiple sources of information, the bee colony method by optimization can significantly limit the number of information sources, identify a narrow range of sources that may be false information. Which in the future will allow you to more accurately identify sources with false information and block them. [ABSTRACT FROM AUTHOR]

Attracting foreign direct investment in the development of post-war Ukraine is impossible without a complete, justified and comprehensive analysis of the degree of investment attractiveness (DIA) of the relevant industrial and infrastructure facilities. Moreover, it is clear that the specified analysis should be based on modern expert system and information technologies and classical decision-making criteria (CDMC). Therefore, today, more than ever, issues of development and implementation of projects in the IT sphere, training of IT personnel, creation and evaluation of attractive conditions for investments are becoming more relevant. The paper is devoted to the development of expert technologies for the construction and analysis of group preference systems (GPS) of experts on a set of characteristic features of investment attractiveness (CFIA) for evaluating DIA IT projects. The system of DIA's advantages is understood as a reasonable ordering (ranking) of these features: from more acceptable, significant, weighty, etc., to less acceptable. DIA evaluation model of IT projects has been developed, which, using the construction of decision matrices on a set of CFIAs and a comprehensive comparative analysis of all received GPS, allows for the selection of the optimally effective CDMC for DIA evaluation of IT projects at an unusually high significance level of α=1%. And the conducted experimental study of the proposed DIA evaluation model of IT projects established, in relation to other CDMCs, the effectiveness of the Savage criterion, since it has an optimization content, that is, it minimizes deviations in GPS in the opinions of both the majority and the minority of the tested. It resulted in the maximum generalized GPS match value that was constructed using other CDMC methods. However, on the other hand, in the CDMC, Savage influenced the appearance of related ranks in the GPS. In addition, the need for an in-depth study of the attitude of the members of the mC subgroup as the most numerous, and therefore reliable, to the significance of the features of the investment attractiveness of the examination objects is substantiated. [ABSTRACT FROM AUTHOR]

The paper considers processes that take place in pulse modulators of power amplifiers and generators. It is demonstrated that the waveform of output modulator pulse is practically completely determined by the parameters of artificial long line that is a constituent part of the modulator. It is shown that to satisfy the requirements for the pulse waveform, one needs to use heterogeneous long lines. The known procedure of such heterogeneous artificial long line synthesis is considered, which allows one to obtain a required pulse form at the modulator output. It is stressed that during this synthesis, an assumption is usually made that the line, which creates required pulse form of the current for shortcircuited load, will create the required pulse form and for the discharge process through the matched impedance. An inference is made about the problem existence that lies in the fact that the mentioned assumption requires verification. The signal waveform at the output of the line requires the assessment of the waveform in the time domain as well. With account of the fact that analytical methods are hard to apply to heterogeneous long lines, the paper proposes as a solution to this problem to use a computer model. Designed computer model was applied to the known from the literature artificial long line, which is composed from five elements and aims to form trapezoidal output signal. During the trial of the artificial long line with the help of simulation computer model, it was established that artificial long line synthesis procedure allows creating the line that, while being discharged over the shot-circuited load, creates the required pulse form. At the same time, while using the model for discharge process simulation over the matched load, the waveform distorts, what points at not totally correct assumption made during the line synthesis. Designed model permits assessing the signal waveform deviation from the required one and gives a possibility to work out a decision as to this waveform improvement. Thus, developed simulation computer model allows one to assess the signal waveform in the time domain at the output of the long line for its different operation modes and check the correctness of the assumption made during the synthesis process. With account of the flexibility and the precision of the designed model, it is possible to use it for long lines parameters verification in pulse modulators, as well as for search of ways of their improvement. [ABSTRACT FROM AUTHOR]

Requirements for information security dictate the necessity of developing new methods of cryptanalysis. Modern cryptanalysis depend on mathematics, in particular on theory and optimization methods. Taking into account the generally recognized requirements for attack resistance of ciphers, the decryption problem should be considered as a combinatorial optimization problem The paper proves the necessary of the development of new methods of cryptanalysis using metaheuristics, contains a retrospective review of publications in the last period in this area. The number of publications indicates the relevance of the research direction. Specialities of the application of the Ant Colony Optimization algorithm to cryptanalysis problems, in particular, factorization problem, are considered. The structure and general principles of the ACO algorithm are described, as well as the adaptation of this algorithm to the solution of a specific problem of combinatorial optimization. Various variants of the fitness function, features of their application, methods of narrowing the search space, rules for choosing the direction of movement on the graph, modification of local search are discussed. The addition of genetic operators of crossover, mutation, and selection is considered as one of the modification options. The conditions for stopping the operation of the algorithm are described. The various facts of using metaheuristics for solving combinatorial optimization problems arising in numerous subject areas, in particular, in cryptanalysis, are described. It is emphasized that since theoretical studies of combinatorial optimization algorithms rarely allow obtaining results that can be applied in practice. The main tool for analyzing their effectiveness is a computational experiment. [ABSTRACT FROM AUTHOR]

Copyright of Science-Based Technologies is the property of National Aviation 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 Science-Based Technologies is the property of National Aviation 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.)

Radar detection of signals containing useful information about surveillance objects is a complex and multifunctional process that combines the solution of various problems, one of which is the detection of moving targets against the background of passive interference. Its solution is based on a fundamental idea based on the application of the Doppler effect, according to which, methods of selecting moving targets were developed, which consist in changing the frequency of the signal reflected from the moving object. Traditional sweep-to-sweep subtraction algorithm of passive interference of MTI systems, are effective when the interference is stationary, but have disadvantages caused by interference with a complex frequency spectrum. As a result, to improve the efficiency of radar detection systems, adaptive algorithms were proposed and investigated, and their advantages were shown. However, the need for further processing and improvement of existing systems and methods remains relevant and is caused by many aspects, one of which is the fact that radar detection systems are forced to function in conditions of interference of various natures, which cannot always be described by a Gaussian model. Thus, the paper focuses on the problem of detecting radar signals reflected from moving targets against the background of obstacles described by a non-Gaussian distribution, and also investigates ensuring the stability of the detection algorithm. The random occurrence of disturbances in the observation process allows for their mathematical representation to use an autoregression model generated by a disturbance described by the Laplace model. As a result, a locally optimal decision rule is synthesized for detecting a signal of a known form against the background of an autoregressive disturbance, which consists in finding the maximum following the signal parameter and the vector of the disturbance parameters of the obtained likelihood ratio, which is the ratio of the hypotheses put forward concerning the obtained sample. The robustness of the detection algorithm is ensured by estimating the unknown parameters of the noise process using an empirical Bayesian approach. In the course of work, the performance of the synthesized algorithm under the influence of non-Gaussian interference, which is described by the K-distribution model, was also investigated. To understand the effectiveness of the proposed detection algorithm, statistical modeling is performed. The simulation results confirm the effectiveness of the synthesized robust algorithm over the non-robust one, the effectiveness of which is manifested in the presence of impulse interference with an increase in the probability of their occurrence, accordingly, it is more resistant to the occurrence of chaotic impulse interference, while the non-robust algorithm gives significant errors, which leads to the deterioration of the detection of the useful signal. [ABSTRACT FROM AUTHOR]

Wi-Fi technology is very relevant nowadays, as wireless communication has become a necessary part of our everyday life. Wi-Fi allows you to connect to the Internet on various devices, such as smartphones, tablets, laptops, TVs, and others. In addition, Wi-Fi technology is constantly evolving and improving. New technology standards, such as 802.11ax (Wi-Fi 6), allow for improved data transfer speeds and greater resistance to interference and interference. However, with the popularity of Wi-Fi technology comes a greater threat to network security. Therefore, it is important to improve security methods and encryption algorithms for Wi-Fi networks to ensure their safety and security. The study of vulnerabilities of Wi-Fi WPA2 and WPA3 wireless communication protocols is very relevant due to the fact that wireless networks are an integral part of the modern world. Since hacker attacks on wireless networks have become widespread, researching WPA2 and WPA3 vulnerabilities is very important for ensuring the security of Wi-Fi networks. After all, WPA2 and WPA3 protocol vulnerabilities can be exploited by attackers to gain unauthorized access to the network and obtain sensitive information such as passwords and user data. This paper will cover such topics as the vulnerabilities of securing WIFI networks using WPA2 and WPA3, the main means of protection against attacks, and a comparative characterization of these two security methods. [ABSTRACT FROM AUTHOR]

Copyright of Science-Based Technologies is the property of National Aviation 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 Science-Based Technologies is the property of National Aviation 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 Science-Based Technologies is the property of National Aviation 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.)

The paper considers the process that precedes negotiations regarding the conclusion of the deal of the voyage chartering of a vessel - evaluation and selection of proposals (offers) of the cargoowner - the charterer by shipowner. The main interests of the shipowner regarding the terms of the first offer are correlated, through the terms of the voyage charter party and the shipowner’s responsibility under it, with the terms for the fulfillment of the voyage proposed by the charterer in the offer. Such terms are the kind and quantity of the cargo, the terms of its readiness for shipment, the (first) port of loading. It was determined that for some of them already at this stage trading by the shipowner is not possible, so he accepts such offers for evaluation only if he is ready to give up his interests already at the stage of preselection of offers. In order to proceed to the next stage - negotiations - it is necessary to compare the voyage expenses on the terms proposed in the offer and the expected income. The cost components largely depend on the duration of the voyage - these are fixed costs and costs for the purchase of fuel; the costs of paying disbursement accounts are determined directly by the ports between which the voyage is proposed to fulfill, their number and the route between them. According to the offer, the voyage freight should be considered as a revenue component. The general order of their calculation is given. It is emphasized that the obtained calculation results are of an approximate nature, because many factors cannot be taken into account at the stage of offers acceptable for consideration by the shipowner, and currently already during the voyage (as a result of the conclusion of the agreement) may slightly change the previous results. Similary, the structure of expenditure and income components cannot be determined with a certain accuracy in preliminary calculations according to the offer. To rank the offers regarding the degree of interest of the shipowner in them, it is suggested to use the level of profitability. It is noted that in the process of further negotiations, the shipowner’s interest in this or that offer depends on the length of the negotiation process, during which both parties (the shipowner and the charterer) can concede their interests regarding the wording of the terms of the offer for the dealing the voyage charter-party. [ABSTRACT FROM AUTHOR]

Today, most telecommunication service providers are interested in making sure that customers are satisfied with the services they receive. It is obvious that users of a certain service will continue to choose the same provider if their expectations of service quality have been met. Therefore, in order to meet customer expectations, providers need to constantly measure the current level of quality of the services they provide. In order to provide the best quality services by telecommunications providers, companies need to consider not only network quality and QoS, but also QoE. Surveying subscribers in view of the expansion of the network and the increase in the number of services provided is no longer a productive process, thus there is a need to ensure consistent end-to-end monitoring of the quality of the user experience. Based on these considerations, this paper proposed to use a machine learning model called "Random Forest" for data analysis, and also step-by-step described the stages of analysis based on historical data. In the course of the study, it was possible to test the QoE prediction method depending on the QoS parameters. It turned out that it is possible to reduce the data set proposed in the second section without affecting the accuracy and performance of the calculations performed by the machine learning model. However, the remaining parameters are predicted with 100% accuracy, which is an excellent result. Thus, the proposed method using machine learning algorithms can be used in its work by telecommunication providers and mobile operators to ensure end-to-end monitoring of the level of user satisfaction with the services provided by the provider. [ABSTRACT FROM AUTHOR]

The substantiation of the requirements for reliability, controllability and maintainability, as well as the determination of the probabilities of errors of the first and second kind during the operation of complex diagnostic tools for systems with built-in software is one of the main tasks that arise at the preliminary stage of development and design of this type of diagnostic tools. The readiness of the object of diagnostics can be characterized by the indicator of readiness - the probability of maintaining the operational efficiency of the object at an arbitrary moment in time when it is used for its intended purpose. This is especially important for complex technical information protection systems at facilities, which consist of many subsystems of various purposes and complexity. The formalized procedure proposed in the paper allows formulating requirements for complex diagnostic tools for computer systems and systems with built-in software in the absence of information about the importance of indicators characterizing the safety of the object at the previous stage of designing technical equipment, and substantiating them in the presence of a minimum amount of information on at the design stage of the latter [ABSTRACT FROM AUTHOR]

Information needs constant reliable protection. Protection against unauthorized access and distribution, accidental deletion or modification. All developed European countries are concerned about the problem of information security, as well as the protection of personal data of the country's citizens. Social networks are one of the main methods of communication, finding connections and sharing both public and personal information. Social networks make up a constantly growing share among general networks. The network itself acquires new properties, acting as an independent factor. Therefore, it is constantly necessary to develop an information protection system, especially the protection of personal data in social networks. The paper analyzes the parameters of social networks. The parameters of the social network are the transfer of information to other users, traffic density, the probability of building a secure network, and others. A mathematical model for determining the security of personal data from trust and the amount of information in social networks has been developed. Mathematical modeling was carried out in the MatLab environment, the simulation proved that, based on the conditions of the dissipation ratio and the natural frequency of fluctuations of the quantity, the decay of the latter to a certain value is carried out periodically, with a decaying amplitude, or according to an exponential decay law. That is, the protection of personal data increases due to the growth of information trust factors. Mathematical modeling of the proposed model, a model that determines the dependence of personal data protection on trust and the amount of information, confirmed the adequacy of the developed model and proved that personal data protection is proportional to trust. The protection of personal data increases with the growth of trust parameters. But the protection of personal data diminishes slightly as the amount of information to be protected grows. This fully corresponds to the real situation and confirms the adequacy of the developed model. [ABSTRACT FROM AUTHOR]

This paper analyzes processes that take place in the type-C pulse-forming networks. Studying of this processes is carried out with use of computer simulation modelling. It is proposed to use implicit Euler algorithm in the pulse-forming network model design. Accordingly, computer simulation model of this pulseforming network was created. Comparative analysis of the performance of the pulse-forming network computer model based on implicit Euler algorithm with the performance of the model that was developed with use of explicit Euler algorithm was done. This analysis demonstrated that for the research object in the form of type-C pulse forming network for the chosen modelling conditions, both models exhibit almost identical precision of the pulse-forming network signals representation. This observation allowed one to make certain that the inferences concerning the correctness of the procedure of the type-C pulse-forming network synthesis made in the previous research are grounded. While studying the results of the two pulse-forming networks models trials in a greatly enlarged scale, it was established that computer simulation model based on explicit Euler algorithm does have a tendency to accumulate errors, what corroborates the inferences known from literature sources. Nevertheless, it is necessary to stress that for a small modelling increment, what is the case in the performed study, error accumulation in the computer simulation model based on the explicit Euler algorithm is insignificant. Designed computer simulation model based on implicit Euler algorithm can be used in scientific research in two major ways. The first way is in its use for other simulation models correctness verification, such as the model based on explicit Euler algorithm. Another way envisions the independent use of this model for the situations in which there is a necessity to secure minimum of errors while performing research of the pulse-forming network with help of the computer simulation modelling. [ABSTRACT FROM AUTHOR]

Copyright of Science-Based Technologies is the property of National Aviation 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 Ukrainian Scientific Journal of Information Security is the property of National Aviation 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.)

The article presents a new way to increase the cryptographic strength of MAC codes for messages transmitted over the Internet. Today, this should make it possible to resist both the consequences of cyber threat aggregation and increase the speed of unauthorized access to data through the creation of such new hardware capabilities as quantum computer technology. The paper proposes to consider the application of the modified UMAC algorithm on modified McEliece elliptic curves using crypto-code structures with hybridity features. The proposed structures were tested for collision properties. For this, a software application was developed in the environment of the object-oriented programming language C#. To determine the capabilities of the studied hash-codes, a complex indicator of the effectiveness of the modified UMAC algorithm was developed. This made it possible to test the proposed designs for resistance to hacking, consider the value of the data that is being protected, and the safe time for a possible hack. As a way to assess this indicator, it was proposed to use the method of multivariate complex analysis. For this, scales for measuring and interpreting each indicator were developed. It has been proven that this method of evaluation allows one to obtain adequate results and combine them with the results of accurate calculations for individual parameters. The issue of reducing energy costs for the formation of crypto-code structures was also investigated. The results showed that the creation of hybrid crypto-code structures leads to the lowest energy costs. [ABSTRACT FROM AUTHOR]

The main purpose of evolutionary optimization is to find a combination of parameters (independent variables) that would help maximize or minimize the qualitative, quantitative, and probabilistic characteristics of the problem. Recently, integrated optimization methods have become very common, borrowing the basic principles of their work from wildlife. Researchers are experimenting with different types of representations, for example, evolutionary and genetic algorithms use selection methods and genetic operators. A large number of algorithms based on the swarm method are known. The artificial bee colony is an optimization method that mimics the behavior of bees, a specific application of cluster intelligence, the main feature of which is that it does not need to understand specific information about the problem, you just need to optimize the problem. Comparing inferiority with the help of the local optimization behavior of each person with an artificial bee finally leads to the appearance in the group of a global optimal value with a higher rate of convergence. The paper considers the method of solving the optimization problem based on modeling the behavior of the bee colony. Description of the model of the behavior of intelligence agents and forage agents, search mechanisms, and selection of positions in a given neighborhood. The general structure of the optimization process is given. Graphical results are also presented, which prove the possibility of the bee colony method to optimize the results, i.e. from all multiple sources of information, the bee colony method by optimization can significantly limit the number of information sources, identify a narrow range of sources that may be false information. Which in the future will allow you to more accurately identify sources with false information and block them. [ABSTRACT FROM AUTHOR]

The paper deals with research into performance of а wideband telecommunication channel with direct spectrum spreading in multipath signal propagation with deployment of adaptive antenna arrays that function according to root mean square error criterion. It is stressed that for root mean square criterion implementation in adaptive arrays, substantial challenge in practical realization is reference signal formation. It is proposed to use for deriving the reference signals wideband signals with direct spectrum spreading that are formed with the help of pseudo noise coding sequences. In using such signals, it is envisioned to deploy RAKE receiver to determine multipath components delays and, in such a way, to obtain reference signals for root mean square criterion. It is stressed that the real wideband signal comprises at least two pseudo noise coding sequences, which spread and scramble the spectrum, and the bit sequence, which transmits the desired signal. Computer simulation of a wideband telecommunication channel is carried out in the conditions of total knowledge of all three components of the wideband signal, two components and only one of them. Computer simulation results allows one to come to the conclusion that lack of knowledge about wideband signal components leads to substantial performance deterioration of adaptive antenna arrays due to impossibility to form the exact reference signal. It is proposed to deploy two approaches to securing adaptive antenna arrays operation in the conditions of incomplete knowledge about the structure of the wideband signal being transmitted in the channel. The first one envisions using discontinued adjustment of adaptive antenna arrays only in the periods of the frame sync pulse transmission, which for the scrambling sequence and the bit sequence of the desired signal always equals unity. The other approach concerns adaptation only in the time intervals with the training sequence transmission, which is known beforehand. It is proposed to carry out further research on studying adaptive performance of adaptive antenna arrays in the discontinuous mode of their adjustment. [ABSTRACT FROM AUTHOR]

Global trends towards an increase in the number and complexity of cyber-attacks led to the actualization of the issue of information and telecommunication systems (ITS) security. In particular, it is important to sectoral ITS, which are critically important for the functioning of society, the socio-economic development of the state and ensuring the informational component of national security. Taking into account the needs of national security and the need to introduce a systemic approach for solving the problem of critical infrastructure protection, at the national level, creating a security system is one of the priorities in the reforming of the defense and security sector of Ukraine. Thus, there is a need to develop methods and models for the ITS categorization as critical information infrastructure to ensure the national security of Ukraine. The paper presents a method for calculating the level of criticality of sectoral ITS, which, due to the use of a structural-logical and functional model for determining the functional profile of the sectoral ITS security, as well as a functional model for calculating the quantitative criterion for assessing the security of ITS, allow to increase the accuracy of the decision to categorize ITS as critical. The use of the developed method makes it possible to make a decision to categorize ITS as critical, taking into account the properties of information (such as confidentiality, integrity, availability, observability). In addition, an experimental study of the proposed method was carried out on the example of the ITS of the National Confidential Communication System (NCCS), which was used to check the adequacy of the methodʼs response to changes in input data. Using the method of calculating the criticality of sectoral ITS, the calculation of the criticality ranks for the functionality disruption of components, subsystems and systems of NCCS was carried out; the calculation of the quantitative indicator of the severity of the consequences of the functionality disruption of NCCS, as well as the quantitative indicator of the rank of criticality of NCCS was calculated and a conclusion was made regarding the NCCS criticality. [ABSTRACT FROM AUTHOR]

In order to ensure the smooth functioning of a social network with a large number of subscribers, it is advisable to divide it into subnets. Division into subnets will provide high-quality control of traffic and other parameters, including security parameters. The first reason for dividing the network into subnets is not to get a huge broadcast domain. The second important reason for dividing the network into subnets is to provide a certain level of security. The third reason is identifying online communities. The necessity of creating a model is determined. In this model graph is randomly generated with specified parameters for internal and external relationships between vertices, and communities are considered extraordinary. A method for isolating the structure of communities based on the maximum likelihood method is proposed, and a numerical random search algorithm is described on its basis. Graphs which representing real social and communication networks are changed rapidly. Moreover, random graphs are an effective tool for studying these networks. An important task is to identify the structure of communities in networks. In conditions of large dimensionality of networks, approximate methods are especially relevant. That allow finding a solution close to the optimal for a limited time. To solve this problem, it is proposed to create a model for distinguishing the structure of communities based on the maximum likelihood method. And a description of a numerical random search algorithm based on created model. This paper describes a mathematical model in which a graph is randomly generated with specified parameters for internal and external relationships between vertices, and communities are considered extraordinary. A method for isolating the structure of communities based on the maximum likelihood method is proposed, and a numerical random search algorithm using the Boltzmann-Gibbs distribution is described on its basis. The behavior of the objective function is investigated. [ABSTRACT FROM AUTHOR]

Copyright of Ukrainian Scientific Journal of Information Security is the property of National Aviation 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.)

The paper proposes an approach to the use of many parametric criteria in the model of decision-making on the functional state of complex objects in which the essence of uncertainty is that in the presence of an unlimited number of states it is impossible to estimate the probability of each of these states. In practice, such objects are characterized by several indicators, which can sometimes be correlated, which creates difficulties in deciding on their condition. The process of developing a decision-making model allows determining the dependence of the functional state of the studied system on the influence of external factors, which can be done due to fluctuations in the measured values of its indicators. However, making a decision based on an independent assessment of the value of each individual parameter may give the wrong result, as there is an interrelated effect. Thus, by using many parametric criteria in decision making, you can improve the decision-making system. While on the basis of a comparative assessment of each parameter with a normalized value, a decision was made on the stability of the system, which studied the use of many parametric criteria revealed violations in the functioning of this system. That is, the use of many parametric criteria gives a more accurate result, in the presence of correlation of individual indicators when deciding on the stability of the system. In addition, the use of the multi-parameter Hotelling criterion also allows determining which parameter caused the malfunction of the system, which can be used for corrective action. Has been demonstrated in these studies. The use of many parametric criteria to determine the functional state of complex objects allows not only to draw conclusions about the violation of their work, but also give the researcher the opportunity to determine which of the indicators had a significant impact on the branching of the whole system. The use of the Hotelling criterion is a more sensitive tool for determining the ramifications of the functioning of systems than the generally accepted method of research on standardized indicators, which was demonstrated in these studies. [ABSTRACT FROM AUTHOR]

The article is devoted to solving the problem of creating a software and hardware complex (SHC) of an automated system of situational centers of state authorities of the security and defense sector (AS SC SA SDS). Relevance. The problem of creating intellectual SC for the SA SDS is nowadays extremely urgent, because the SDS is responsible for the national security of the state as a whole and separately for each citizen. Formulation of the problem. The work examines the system of the SC SDS for security forces as a multi-level one, which has three levels of management - strategic (state), operational and tactical. Since, from a technical point of view, the SC is a software and hardware complex designed for personal and collective analytical work of managers (commanders), the study of the problem of creating a standard software and hardware complex is a necessary component of research devoted to the automation of these structures. The aim of the work is to study the basic requirements for a typical SHC and its composition, which should ensure the functioning of the AS of the SC SA SDS at the strategic, operational and tactical levels of control in the security forces. Results. The paper analyzes the features and provides the requirements for the AS SC SA SDS. The spatial, organizational, informational, technical and software integration of the AC system components is considered. The requirements for informational, technical and software compatibility of the AC SC components are given. There is a list of types of AS that are deployed at different levels of management. The generalized architecture of the SC SDS system is shown, the composition of mathematical, hardware and software is proposed, which should be part of the standard hardware and software complex of the AS SC SA SDS. The basic modeling complex (BMC) is described as a means of simulation modeling of a typical software and hardware complex of the AS SC SDS, the model of which is formed using a systematic approach. The main capabilities and a brief description of the BMC subsystems are given. It is noted that to demonstrate the work of the BMC, a model has been created, which is deployed at the Institute of Mathematical Machines and Systems Problems of the NAS of Ukraine. On the model, using the example of the hierarchical structure of the Armed Forces of Ukraine, the work of the military command and control bodies of the strategic, operational and tactical levels is imitated. Conclusions. The results of the research can be used to create an automated system for the SC of state authorities in the security and defense sector. [ABSTRACT FROM AUTHOR]

This paper reviews the known error correction methods for QKD systems, identifies their advantages and disadvantages. The method of LDPC-codes is substantiated for improvement. Noise errors can occur when exchanging qubits between Alice and Bob through the quantum channel, and Bob may receive erroneous values when measuring states that need to be corrected in the post-processing phase. The verification matrix for LDPC codes is quasi-cyclic, ie each subsequent row of the matrix is cyclically shifted to the right by one bit relative to the previous row. This allows not only to describe the matrix only by the first line of the matrix, but also to use the property of isomorphism of circulating matrices with a ring of polynomials over the Galois field. That is, the verification matrix can be described by a certain polynomial. And the operations performed on this polynomial are applied to the matrix. Using such isomorphic properties of polynomials makes it much easier to create and store not only a test matrix but also a generating matrix, which avoids long-term matrix multiplications and the use of more memory to store matrix data, greatly simplifying hardware implementation. The code word is created by the method proposed by the author of LDPCcodes R. Gallagher. The decoding of code words in the original message uses a "soft" algorithm for spreading trust (belief-propagation algorithm) or sum-product algorithm (SPA), which has proven its effectiveness and is used in modern telecommunications systems. An algorithm for generating a verification matrix and an algorithm for generating a generating matrix based on the method for finding the inverse Euclidean-Wallis polynomial have been proposed and adapted for writing program code. Software has been created that implements the above algorithms, which can be found on the git repository. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental studies of the volumetric wear rate and friction coefficient when using fullerene compositions in the lubricant and changing the loadspeed range of operation. The rational content of fullerene composition consisting of fullerene fine powder, pre-dissolved in vegetable high-oleic rapeseed oil, is substantiated and experimentally confirmed. It is proved that a rational concentration can be a theoretically substantiated and experimentally confirmed average value: 0,75 g/kg of fullerenes + 99,25 g/kg vegetable high oleic oil, as a solvent, followed by addition to the base oil. The direction of reducing the volumetric wear rate by increasing the concentration of the fullerene composition is more than 100 g/kg can be considered ineffective and experimentally confirmed. Experimental results have been obtained that confirm the hypothesis of the formation of a lubricating film on the friction surface of tribosystems in the presence of fullerene compositions in lubricants. The degree of influence of fullerene compositions on the volumetric wear rate is established, which allows to draw a conclusion about the adequacy of the developed mathematical model to the experimental data. The decrease in wear rate is 20...25%, the simulation error is 5,2...14,0%. Experimental studies have shown that the use of fullerene compositions most effectively reduces the coefficient of friction (by 32,4 ... 86%), compared with the wear rate (by 20 ... 25%). Based on these results, it is concluded that the fullerene composition in liquid lubricants is antifriction and to a lesser extent antiwear. It is experimentally established that the use of fullerene compositions in lubricants has a rational load-speed range of operation. In this range there is a maximum reduction of the coefficient of friction. [ABSTRACT FROM AUTHOR]

Copyright of Ukrainian Scientific Journal of Information Security is the property of National Aviation 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 Ukrainian Scientific Journal of Information Security is the property of National Aviation 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.)

The work is devoted to a rather urgent problem — the study of sequences and generators of random numbers, working on devices with limited resources, for randomness. The analysis of random sequences and random number generators is a rather specific task, but one or more of numerous test packages can be used to solve it. However, the analysis performed indicates that the existing tests have a number of drawbacks, the solution of which can reduce the prerequisites for testing and improve the accuracy of the results. The paper presents the types of random number generators and their disadvantages. Described is a lightweight and fast pseudo-random number generator useful for resourceconstrained devices such as those used in the IoT. The article is devoted to the development of lightweight pseudorandom number generators. The principles of designing a lightweight pseudo-random number generator are described. Requirements for the quality of a lightweight pseudo-random number generator are formulated. The construction of a physical model of a lightweight pseudo-random number generator was considered. The physical model of the IoT generator, which is presented in the work, by its example provides a broad overview of the factors and limitations that arise in the design of generators. The process of testing and optimizing a lightweight pseudo-random number generator is recommended using tests of multivariate statistics. These tests illustrate the suitability of the software package for use and its integral role in creating a quality random number generator, especially for use in IoT devices. The software product that was created in this work can be used to solve a wide range of tasks, as has already been repeatedly noted. One of the most important, and indeed the one that can receive invaluable benefits in the field of application, is cryptography. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental research aimed at confirming the adequacy of the developed mathematical models method of forming a wear-resistant lubricating film on friction surfaces in the presence of fullerene compositions for different base oils. From the analysis of the presented experimental values and their comparison with theoretical dependences it follows that the mathematical model of formation of a lubricating film on a friction surface of triboelements, which is developed in previous works of the authors, adequately reflects the process of friction and wear and is in a functional relationship with the wear rate and coefficient of friction. Experimental studies have confirmed the theoretically obtained in previous works, the use of fullerene composition, consisting of a solvent-vegetable oil and a fine powder of fullerenes, reduces the rate of wear when changing the tribological properties of base oils by 20,1 ... 22,6%. The simulation error is 6,5 ... 9,2%. Based on experimental studies, it is concluded that the introduction of fullerene composition in base oils with low values of tribological properties reduces the coefficient of friction by 18%. The maximum effect of reducing the coefficient of friction is equal to 71 - 86%, characteristic of base oils with average values of tribological properties. Experimental studies have confirmed that the increase in the concentration of fullerene composition in the base oil from 50 g/kg up to 150 g/kg allows to reduce the volumetric wear rate and the coefficient of friction between these concentrations by 7,8% (theoretical result 6,4%). Therefore, the direction of reducing the volumetric wear rate and friction coefficient by increasing the concentration of the fullerene composition more 100 g/kg can be considered ineffective and experimentally confirmed. [ABSTRACT FROM AUTHOR]

In the presented work, a technique for diagnosing various designs of tribosystems using acoustic emission methods has been developed. The development of the methodology is based on the following assumptions. The activity of acoustic emission during the operation of the tribosystem will depend on the rate of deformation of materials on the spots of actual contact. The total acoustic signal from the friction zone is formed as a result of the interference of the primary acoustic signals from the spots of actual contact with the friction surface, satisfying the coherence condition. Based on these assumptions, the paper presents an expression for calculating the informative frequency, which will be generated by the tribosystem during operation. The diagnostic technique contains the following steps: determination of the informative frequencies at which it is necessary to register the amplitudes; determination of amplitude values that carry maximum information; dividing the general acoustic signal into clusters and establishing a functional relationship between the values of the peak factor of the clusters and the values of the friction coefficient, wear rate and running-in time of tribosystems in online mode. The work substantiates the values of the informative amplitudes of various clusters in relation to the base cluster. It is shown that an increase in the informative frequency from 250 to 500 kHz, increases the value of the informative amplitude by 17,6...43,75%. The results obtained indicate that this fact must be taken into account when developing methods for diagnosing tribosystems. The use of the developed technique will increase the robustness of the tribosystem diagnostics method and identify surface processes during wear. [ABSTRACT FROM AUTHOR]

In this work, the process of vacuum membrane distillation in the process of extracting ethanol from molasses solution was investigated. The growth of biofuel production (especially anhydrous ethanol) stimulated the search for new methods that allow to extract and concentrate it in a more efficient and profitable way; membrane technology is one of them. Membrane distillation, intended for the extraction of alcohols, is a technique using porous membranes to separate the liquid mixture, in which the driving force of the process is the partial pressure gradient on the membrane. During the process, the volatile components must change phase to pass through the membrane. The main advantage of this method is the possibility of continuous removal of ethanol at the stage of production of fuel alcohol. Membrane distillation with vacuum, designed to reduce alcohols is almost not studied. The urgent task is to create a mathematical model of the process. In this paper, a mathematical model of the dynamics of temperature and concentration at the outlet of the membrane module is developed. The formulated assumptions are accepted at development of mathematical model of process. The mathematical model takes into account the change in the concentration of ethanol in the solution at the outlet and in the vapor diffusing through the membrane. Possible control effects are considered to be the change of vacuum in the permeate channel and the flow of cooling water for condensation of ethanol vapors. . Static and dynamic characteristics of the control and perturbation channels are determined on the basis of the created mathematical model of the process. The influence of assumptions on the type and nature of dynamic properties is investigated. The system was studied in the state space. The finite difference method is used to solve the mathematical model using the Matlab software tool. The graphic results of the research are given. [ABSTRACT FROM AUTHOR]

The paper proposes an approach to assessing the state of the organism by determining the adaptive potential. The functional state of the organism can be assessed by the degree of adaptation to environmental conditions, and since the degree of adaptation is determined by the body’s response to environmental influences this assessment also contains a prognostic component. The instantaneous balance between the state of the organism and the environment, which is determined by the stock of functional reserves, is considered as the current functional state of the organism. The functions of the organism are maintained in a state of equilibrium only when the conditions of the external environment fully meet its needs. If the conditions of the external environment, including production, change, become unfavorable, complicate its vital functions, then to counteract them the body directs special mechanisms that maintain the stability of the internal environment or change it within the limits set by physiological laws. Such mechanisms of adaptation (adaptation) are a dynamic process due to which the body maintains the constancy of the internal environment in a changing external environment. Therefore, the assessment of the adaptive reserves of the organism must be considered together with the conditions of external influence as one of the components of the current functional state of the organism. Thus the quantitative estimation of adaptive possibilities needs to be carried out taking into account correlation of separate parameters which are components of the given estimation.The paper proposes to improve the method of estimating the adaptive reserves of the organism by determining the adaptive potential using Hotelling maps, which allow to test the hypothesis of biological stability of the objects of study. It was found that the use of Hotelling maps for the evaluation of such complex systems as the human body gives more reliable results compared to existing methods. The use of the approach taking into account the adaptive potential with the use of Hottelling maps, to determine the disorder of biological objects, allows us to conclude that the adaptation reserves and the functional state of the organism. This is especially important for deciding on the professional suitability of professions with extreme external destabilizing factors. [ABSTRACT FROM AUTHOR]