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Introduction. The paper considers improving the management quality of an educational organization through automating the personalized data collection, storage and ranking. The authors have developed a module of the university corporate system, an ePortfolio of students, which implements a multicriteria optimization method for calculating the students’ rating on the basis of the collected and stored data. The study object is multicriteria ranking methods. The subject of the study is the automated calculation of student’s rating within the electronic portfolio. The study objective is to develop tools for collecting, storing and processing data on individual achievements of students and the implementation of the mathematical method of multicriteria optimization for ranking students on the basis of the portfolio data. Practical implications include development of a tool for an effective management of the educational process.Materials and Methods. A prototype module of the university corporate system “ePortfolio” on the platform of 1C: Enterprise 8.3 is presented. To rank students, a special case of the alternative ranking method is implemented in the block of the data analysis module – pairwise comparison in order of their relative importance. At that, a unified scale of relations was used.Research Results. The authors described the scheme of the information system (IS) operation “ePortfolio”, presented a process interaction pattern for the portfolio formation, as well as a diagram of business processes under calculating an individual rating. A fragment of the sample is shown on which the performance of the multicriteria optimization block has been tested. The criteria of the calculations are described, as well as the rule of screening alternatives for solving for the optimum.Discussion and Conclusion. The paper presents the results of the IS block operation on ranking a list of students. The calculation results coincide with the practical data.

Introduction. The paper discusses the applicability of a riskbased approach in the “personnel-machinery-production environment” system at the facilities running tower cranes through the introduction of IT-technologies that provide open communication of the staff, management team of the operating organizations, and the National Supervisory Authority, to reduce the accident rate. Materials and Methods. An example of a hazardous production facility running tower cranes is given. Materials on the analysis of operational status of tower cranes within the framework of the current legislation in the field of industrial safety are used. The necessity for innovations and transformations, one of whose methods is the risk-based approach allowing for the implementation of all required levels of control, is identified.Research Results. The stages of introduction of the riskoriented approach for tower crane operators implemented through IT-technologies using Web-applications on safety management under the tower crane operation based on the hazard analysis and risk assessment in gamut, algorithmically associated with the electronic block key of its local security system, are determined.Discussion and Conclusions. The application of a risk-based approach in the “personnel-machinery-production environment” system at the facilities running tower cranes through the introduction of IT-technologies will ensure the proper operation of all departments and each participant of the operation, as well as provide Supervisory bodies with an opportunity to access information on the operation for the implementation of control and supervision functions remotely.

Authors describe a two-stage traffic assignment model. It contains of two blocks. The first block consists of model for calculating correspondence (demand) matrix, whereas the second block is a traffic assignment model. The first model calculates a matrix of correspondences using a matrix of transport costs. It characterizes the required volumes of movement from one area to another. The second model describes how exactly the needs for displacement, specified by the correspondence matrix, are distributed along the possible paths. It works on the basis of the Nash--Wardrop equilibrium (each driver chooses the shortest path). Knowing the ways of distribute flows along the paths, it is possible to calculate the cost matrix. Equilibrium in a two-stage model is a fixed point in the sequence of these two models. The article proposes a method of reducing the problem of finding the equilibrium to the problem of the convex non-smooth optimization. Also a numerical method for solving the obtained optimization problem is proposed. Numerical experiments were carried out for the small towns., in Russian

Principles of implementation of current protection of elements of electric power systems with power transformers are considered. In some cases, in facilities with power transformers there could be an inrush of a magnetizing current that can cause a false positive current protection. The special measures of blocking of current protection ought to be taken to avoid this. The methods of implementation of blocking digital current protection when magnetizing current inrush takes place are described. The main way of blocking protection from magnetizing current inrush is tuning-out by harmonics content. The presence of lower harmonics content serves as a criterion of permitting operation of the protection and the higher harmonics content, on the contrary, indicates the appearance of magnetizing current inrush and is used to block the protection action. The operation condition of blocking of digital protection from magnetizing current inrush is presented. A realization of digital part of implementation of current protection blocking is described and the functional scheme of the latter is considered. The scheme contains conditioners of orthogonal components of signals of the first and second harmonics as well as the filters of positive and reverse sequences and blocks of determination of amplitudes. The blocks compute current amplitudes of first harmonic of positive sequence and the negative sequence current of the second harmonic with the use of the orthogonal components. By these values the characteristic quantity of blocking is calculated, which is compared with the activation setpoint. The improvement of performance of the principles of blocking current protection of electric transformers with current magnetizing inrush has been suggested by incorporating the digital part the block of the maximum value formation that determines the maximum amplitude of the first harmonic of the total current into the functional block scheme.

Актуальность исследования обусловлена необходимостью преждевременного определения не только поверхностного распределения трещин, но и степени внутреннего растрескивания горной породы при оценке трещиноватости основной породы применительно к месторождениям облицовочного камня. В современной практике при разработке месторождений облицовочного камня в большинстве случаев исследования трещиноватости ограничиваются лишь визуальным картированием, что не дает возможности получить представление о внутреннем пространственном распределении трещин, которые, в свою очередь, будут определять направление разрушения породы при отработке массива скальных пород. От правильного и рационального решения этой задачи зависит дальнейшая разработка месторождений облицовочного или строительного камня. Решение задачи локализации пространственного распределения трещин может базироваться на привлечении современных технологий, прочно внедрившихся в практику инженерной геофизики и позволяющих без деформирования и вмешательства в поверхность проводить исследования пространственной ориентировки трещин в массиве породы. Аналитические исследования и экспериментальные наблюдения в естественных условиях обеспечивают возможность предварительно дифференцировать исследуемую территорию по степени трещиноватости массива горной породы, а также произвести качественную оценку блочного сырья. Цель: выбор оптимального комплекса геофизических методов, обеспечивающих изучение распространения и локализации трещиноватости в массиве горных пород. Методы: георадиолокационные исследования с применением прибора ОКО-2 с антеннами 150 и 1200 МГц. Результаты. На основе проведенного изыскания предложено использование двух типов антенн с целью проникновения на различные глубины. Получена общая характеристика месторождения блочного камня, произведено выделение исследуемой площади по степени трещиноватости. Представленные методы отображают эффективность исследования трещиноватости на месторождении облицовочного камня методом георадиолокации. The relevance of the study is specified by the necessity not only to identify the surface distribution of cracks, but also the degree of vegetation of the rock when evaluating the fracture of the main rocks as applied to the facing stone deposits. In modern practice, when developing deposits, the rock with various types of distributed cracks can be detected. The further development of deposits of facing or building stone depends on the correct and rational solution to this problem. The solution to the problems of localization of the distributed propagation of cracks can be based on the attraction of modern technologies and introduction of engineering geophysicists into practice, allowing research based on the study of spatially oriented cracks in the rock mass. Analytical studies and experimental observations in natural conditions make it possible to preliminarily differentiate area of study by degree of demolition geological material mass, as well as to make a qualitative assessment of block raw materials. The main aim of the research is to select the optimal complex of geophysical methods for studing the propagation and localization of fractures in a rock mass. Methods: GPR studies using OKO-2 equipment with 150 MHz and 1200 MHz antennas. Results. Based on the study, the authors have proposed to use two types of antennas for penetrating to different depths. The general characteristic of the block stone deposit is obtained, the study area is allocated according to the degree of fracture. The presented methods reflect the effectiveness of the study of fracturing in a facing stone deposit using georadar.

The paper considers new methodologies pertaining to on-board diagnosis of wear-out rate for friction linings of a clutch driven disk and friction discs of a hydraulic press clutch of transmission gear boxes which are based on physical process that uses friction work as an integrated indicator. A new methodology in determination of life-span rate for engine oil has been developed in the paper. The paper presents block schematic diagrams for on-board monitoring of technical state for power units of wheeled and tracked vehicles. Usage of friction work as an integrated indicator for determination of wear-out rate for friction linings of clutch driven disk and friction discs of a haydraulic press clutch makes it possible timely at any operational period of wheeled and tracked vehicles to determine their residual operation life and forecast their replacement.While taking volume of the used fuel for determination of engine oil life-span rate it permits quickly and effectively at any operational period of wheeled and tracked vehicles to determine residual useful life of the engine oil and also forecast its replacement.

The article deals with thermoelectric cooling (TEC) device to provide thermal mode power electronics systems cluster design, are areas of constructive solutions use the feasibility study of the device, a description of the experimental facility and methodology of the experiment, the dependences of temperature on the simulator of the electronic board from the exhaust of the feasibility study power, temperatures of hot and cold junctions, the speed of the air flow and the distance between the electronic boards.

Strakhov's mounting algorithms for solving nonlinear inverse gravity problems are considered from the point of view of the concept of problem-oriented methods of conditional minimization, which make up the core of any technology for quantitative interpretation of gravity data. The comparative analysis of editing algorithms has revealed their main advantage, which lies in the ability to bypass the richly "acute angles" in the theory and practice of interpretation of potential fields, have become a stumbling block for most known approaches to solving inverse problems, which rely on classical methods to solve the conditions of no-extremal problems . At the same time, the question of the actual resolution of the editing method remains unresolved, the answer to which can only be given by a large-scale computational experiment. In this article, this gap is partially filled.