Currently, Russian Railways (RZD) is characterized by an increase in the weight of trains, an expansion of the fleet of sections with high-speed movement of electric rolling stock. All this leads to the complication of the modes of operation of the power supply system, increased responsibility and possible damage from the downtime of trains. Of particular importance are the monitoring systems of the contact network, as an element of the power supply system that does not have a reserve. A significant number of Russian Railways sections are subject to the formation of ice and, as a result, possible serious operational risks and costs. One of the directions of minimizing the damage from the formation of ice and measures to eliminate it, according to the authors, is automation. The article provides an assessment of the possibility and directions of automating the fight against ice on the basis of ice detection systems at the early stages of education.

Keywords: power supply system, correct functioning, automation, ice detection system, contact network monitoring

Designing function interface in the form of function prototype is an important skill in programming. In this article, we discuss the problems of designing function prototypes in the C programming language. This learning task requires performing 5 different steps. Students can make mistakes at each step. These mistakes can concern misconceptions of function's action, identification of data elements, determining of conceptual-level data types for data elements, data elements' directions, inconvenient naming of function and parameters, and syntax of the C language. Modern solutions for analyzing program code and checking student-written code do not detect all these mistakes in the function-interface design. Existing approaches are based on general solutions for seeking errors in program code so they cannot provide informative feedback about semantic mistakes in designing function interfaces. We propose developing an automatic tutor which should guide students through the process of designing function prototypes step by step, detecting and explaining mistakes at each step and providing hints to help fixing the found mistakes. The tutor should allow natural variability in the function interface. In order to deal with various possible representations of the data passed to and from function, the tutor should work with a formal subject-domain model and a model of the target programming language.

Keywords: automatic tutors, requirements for tutoring systems, introductory programming learning, tasks with complex result, multi-step tasks, online education, mixed education, automatic grading

The article discusses the features of numerical modeling of the limits of fire resistance of structures under the influence of standard and hydrocarbon temperature regimes. After carrying out the assessment using the proportionality coefficient, it is necessary to carry out a verification calculation of the structure tested under the standard temperature regime of the fire, and if the results obtained coincide, the calculation of the structure under the hydrocarbon regime.

Keywords: fire resistance of concrete building structures, standard fire temperature regime, hydrocarbon fire regime, fire resistance

The article is devoted to the problem of forming a set of corrective measures to deal with a set of the bank's arrears contracts. The problem at hand is topical practically for each bank. Formed set of measures should be adapted to the time and resource capacity of the employees of bank's specialized subdivision, to the predicted effectiveness of the measures and to the requirements of the bank's policy of customer loyalty. The proposed method of solving the problem of managing the contracts of arrears portfolio is based on a multi-criteria optimization model. Multicriteria is explained by the need to consider various criteria of efficiency and predicted effectiveness of the formed set of corrective measures. In order to find the optimal solution for the multi-criteria task, a special genetic algorithm is developed. The algorithm forms a set of non-dominant alternative solutions, which can be chosen by a decision maker. The article gives a brief description of the main steps of the proposed genetic algorithm and computational experiment on the basis of the developed software.

Keywords: Key words: arrears portfolio, multi-criteria optimization model, set of corrective measures, genetic algorithm, set of Pareto-optimal solutions

An ontology is a formal, explicit specification of a shared conceptualization of some fragment of domain, which is understandable for both people and intelligent systems. However, it is rather complicated for a domain expert with limited ontology expertise to create complete and consistent ontology, which could answer required competency questions. In this paper we consider the approach with the use of ORM2-diagram as an intermediate model for creating an OWL2-ontology. This approach requires specialized conversion rules allowing to map ORM2-diagram into OWL2-ontology. In this study we revealed that existing conversion rules do not comply with ORM2-semantics. We improved existing conversion rules for Entity Type and Subtyping elements of ORM2 notation. Also we automated the process of mapping ORM2-diagram (consisting of base elements of ORM2 notation - Entity Type, Value Type, Subtyping, Unary Role, Binary Role) into OWL2-ontology as well. As result of this study, we developed a software component, which is part of plugin for ontology editor Protégé. This paper also describes an experiment that confirms the effectiveness of the developed module. It is proven that module allows to exclude mistakes encountered in conversion ORM2-diagram to OWL2-ontology and to reduce conversion time as well.

Keywords: explicit knowledge representation, visual model, intermediate model, ontology modeling, ontology, OWL2, ontological pattern, ORM (Object-Role Modeling), ORM diagram

This paper presents an analysis of the results of studies that relate to the rational use of waste products from the production of slab insulation based on polyisocyanurate foam (PIR). Its use as a filler for structural and heat-insulating materials based on cement and gypsum binders is considered, optimal compositions for obtaining products that meet the required performance characteristics are described.

Keywords: polyisocyanurate foam, PIR, thermal insulation, production waste, recycling, cement binder, gypsum binder, lightweight concrete

Urbanization and the growth of the urban population directly affect changes in the urban environment, the emergence of new problems related to ecology, comfort, safety and management. The favorability of the urban environment directly affects the attractiveness of the city and the city's compliance with modern standards of quality of life. This article discusses the criteria for the quality of the urban environment and, in particular, indicators for assessing its safety on the example of the city of Rostov-on-Don.

Keywords: urban environment, environment, territory, city, landscaping, safety, landscaping

CLT panels (English: Cross Laminated Timber) were chosen as the object of the study. This is a multilayer material made of coniferous and hard-leaved wood, which has a system of cross—glued wood in its composition. As part of the work, the available literature on this topic was analyzed, the calculation and analysis of the results obtained were carried out. The article presents the results of the calculation of the CLT panel with consideration of the possibility of isotropic and orthotropic setting of the stiffness of the panel, using elastic modules along and across the fibers. The calculation results are presented in the form of maximum deflections of the panel. Applications in the calculation of the modulus of elasticity across the fibers and taking into account orthotropic stiffness clarifies the stress-strain state of the overlap panel. Based on the calculations performed and the analysis of the results obtained, conclusions are drawn.

Keywords: CLT-panel, transverse bending, modulus of elasticity, stiffness, stress, deflection, orthotropy

The presented article deals with flat roofs of triangular trusses with the development of the structural form in one longitudinal direction. Bearing structures of trihedral trusses are used for public and industrial buildings and constructions. Using the modular system as a result of cross structural division of the structures of triangular trusses allows to carry out their safe transportation to the place of storage or construction. The peculiarities of formation of the modular system taking into account structural peculiarities of the layout of spatial trihedral trusses are considered. By the results of a comparative analysis of the deformability of mathematical computational models of three-sided trusses in the roof, the use of pliable module coupling assemblies was substantiated. The possibility of using different element composition of rods within each module of a triangular truss is confirmed.

Keywords: modular system of a trihedral truss, structures of non-centered truss-less knots; spatial-string computational model; deformability of modular systems with rigid and compliant mounting knots, comparative analysis of computational models

Due to the increasing pace of construction and overhaul of roads, there is a need to introduce more economical and efficient technologies. One of such technologies is soil stabilization. Based on the study of various scientific literature and project documentation, typical soils of the foundation and roadbed of the Kirov region have been established, and their features have been identified. During the study of the soils of the region, several dangerous geological processes were discovered that affect the operation and construction of roads. The article analyzes various methods and techniques of stabilization of heaving soils, as well as possible design solutions for the construction of a layer of modified soil. In addition, the mechanisms by which stabilization is carried out and cases of their application were given. In the course of the study, the main types of stabilizing additives, their features and principle of operation were considered. In order to identify the degree of influence of various binders on the technological sequence of construction, variants of schemes for the production of work on soil reinforcement are presented, depending on their types. According to the results of the study, it was concluded that the stabilization technology is one of the most modern, efficient and cost-effective and provides various advantages in comparison with other alternative methods of strengthening of heaving soils. The relevance of this method for the Kirov region is also proved.

Keywords: road, construction, technology, stabilization, soils, additives, recycler, binders, soil cement, heaving, strengthening

The expediency of using modeling using the finite element method to study the influence of certain prescription-technological factors on the resulting temperature fields and temperature stresses during the construction of massive foundation slabs is substantiated. A simplified method for determining thermal stresses based on the reduction of a three-dimensional problem to a one-dimensional one based on the hypothesis of flat sections is considered. The dependence is proposed and the quantitative values ​​of the parameters for calculating the kinetics of heat release of concrete in the temperature-shrinkage block are substantiated. As a result of the implementation of a numerical experiment on the influence of the duration of breaks between overlapping layers, the temperature of the environment and the concrete mixture, the class and kinetics of concrete hardening, and heat transfer parameters, the dependences of the level of tensile stresses on these factors over time were obtained. It is shown that when developing technological regulations for concreting, the determination of technological parameters (the intensity of laying the mixture, the thermal resistance of the formwork, the arrangement of working joints, etc.) is impossible without taking into account the kinetics of concrete hardening, determined by the prescription features of concrete mixtures.

Keywords: massive monolithic structures, temperature fields and stresses, prescription-technological factors, heat release of concrete, stress-strain state

Technical and economic peculiarities of construction and exploitation of these unique buildings should be considered during the project. One of the peculiarities are the ability to save city´s space, to be main architectures of the city. The most important organizational economic targets of a diversification of management are presented by innovative activity of the industrial enterprise.

Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production

Based on available literary and photographic sources, the architectural, spatial and planning methods of reconstructing railway stations into transport interchange complexes are analyzed and the main ones are identified. The conclusion is made about the most important methods of reconstruction from a functional and planning point of view, which allow transforming stations into modern transport interchange complexes.

Keywords: transport interchange complex (TPC), transport system, transport complex, railway station, railway station, transport junction, railway junction, modernization of the station, reconstruction, reconstruction of the station, methods of reconstruction

The article highlights the main factors that determine the direction of development of housing construction and housing policy. Data on programs to support individuals and legal entities for the development of housing construction are given. The data on the commissioning of residential buildings in the Russian Federation, depending on the type of area, are presented. The analysis and assessment of the growth rate of commissioning of residential buildings was carried out and the factors contributing to their increase were identified.

Keywords: residential construction, real estate, affordable housing, citizen support, growth rate, housing policy, construction industry, standard of living, housing

Dependences of strength and deformation properties of heavy concrete under early loading under conditions of negative temperatures are obtained on the basis of experimental data. Empirical coefficients are proposed to describe the measure of concrete creep through the temperature function. A significant increase in the strength of concrete hardening under load during freezing and thawing has been confirmed. The results can be used to assign the parameters of early loading and calculation of monolithic buildings at the stage of their construction.

Keywords: monolithic buildings, building structures, heavy concrete, strength, deformation, creep, creep measure, early loading, loading intensity

The article deals with the structural forms of spanning trihedral trusses used as load-bearing structures of flat roofs of buildings and structures of various purposes. An algo-rhythm for arranging tubular belt bars from rolled elements with layout conditions for a channel and an angle is presented. Based on the results of numerical studies, the stressed elements of the spatial strut system have been determined. Also, based on the results of the comparative analysis of the deformability of the computational model of a triangular truss, the application of prestressing with a mechanical tensioning device on the stops in the ends of the lower longitudinal rod has been substantiated.

Keywords: prestressed trihedral truss, compound profiles of longitudinal cores, non-centred nodes, spatial-core design model, schemes of application of nodal design loads, deformability, evaluation of numerical results

This article is devoted to finding the key geometric characteristics of circular arches by graphical and analytical methods. Also in this article, algorithms for solving the problem of finding geometric characteristics by graphical and analytical methods are analyzed and these methods are compared in terms of speed and ease of use. Today, you can solve geometric problems in numerous graphic editors. Such editors allow you to quickly calculate the necessary geometric characteristics of any design, for this it is enough to draw a drawing in the software package, the required data will be obtained automatically. However, there is another method for solving such problems, for example, using formulas. This method is based on the principle of an algorithm or a sequence of formulas, thanks to which it is possible to obtain unknown characteristics by setting known characteristics, as well as to solve the inverse problem. Also, this method allows you to create software based on the algorithm, which will greatly simplify and speed up the solution of such a task. The purpose of the research described in this article is to create an algorithm for solving problems of finding geometric characteristics of a circular arched structure according to known mathematical formulas, followed by the implementation of this algorithm by programming tools in Excel.

Keywords: arch, geometry, calculation methods, rectilinear segments, rotation angles

During operation, the pipeline is threatened by various geological hazards, especially in regions with permafrost, where freeze-thaw disasters have a significant impact on the integrity and safety of oil and gas pipelines. Therefore, at the design and construction stage, it is advisable to analyze various methods of laying pipelines, taking into account the topographic environmental conditions, as well as the effect of frost rise and thaw on the soil of the pipeline foundation. An analysis of the existing design schemes for the construction of pipelines, the conditions for passing the route of the projected pipeline, the characteristics of the pumped hydrocarbons makes it possible to justify the choice of a construction method that can ensure the stable position of the oil and gas pipeline both during the construction period and during its operation.

Keywords: hydrocarbons, analysis, pipeline, construction methods, reliability of pipeline structure, permafrost soil, pile support

One of the main socio-economic tasks of the Rostov region is the development of the construction complex. The construction complex affects the interests of the majority of residents of our country and is one of the most important sectors of the country's economy.

Keywords: construction complex, comprehensive assessment of the territory, subject of the Russian Federation, territorial planning, Rostov region"

The article considers possible ways to increase energy efficiency of ventilation systems in residential buildings via replacing natural ventilation by means of mechanical systems with heat recovery of exhaust air. A feasibility study has been completed covering the application of the central zone and single apartment mechanical air-handling ventilation units with respect to social and planning solutions approved in the course of renovation of residential buildings under Volgograd specifics, which showed that the single apartment systems are not economically viable for use with smaller apartments in terms of number of rooms and overall area (economy housing).

Keywords: energy saving, natural ventilation, the mechanical central zone ventilation system, the single apartment ventilation system, recovery, a planning solution for a building, economic feasibility

The problems of modern methods of building construction, namely the obsolescence of construction technologies and the production control system at most facilities under construction do not provide the required level of quality. Due to low-quality materials, formwork, reinforcement, laying and ramming, defects and deviations from the most important requirements for the finished product appear and resource costs increase significantly. Therefore, in order to develop and introduce effective measures to improve the existing methods of building construction, this paper lists the main disadvantages of the technologies used. The practice of applied innovative technologies that can increase the quality and speed of the structures being built is given. The technologies of erecting buildings using various fixed formwork designs are considered.

Keywords: sound insulation, shock noise, residential buildings, noise insulation, air noise, monolithic house, comfortable environment, noise, construction, materials

The main features and goals of energy efficiency in residential construction are considered in order to ensure minimal heat loss of buildings, and thus reduce the use of the required amount of energy to compensate for heat losses. With the increasing energy crisis and the deterioration of the environmental situation in large cities, recently foreign countries have attached importance to the rational use of energy resources. Facades are one of the main elements that provide a solution to improve the energy efficiency of the building itself, as they reduce the heat loss coefficient to a significant level. Today, Germany is a world leader in energy efficiency, as the country uses the most modern energy saving technologies. The technology of using energy-efficient facades in Europe is already considered normal and at the moment the technology of using a ventilated facade, translucent facade system, "green facade", dynamic facade represent more progressive solutions to improve energy efficiency.

Keywords: energy efficiency, heat loss, enclosing structures, facade, foreign experience, hinged ventilated facades, translucent facade system, green facade, dynamic façade

The main recommendations for the installation of a gas pollution detector in domestic premises are considered, an experiment is conducted using the Altair 4x gas analyzer, the purpose of which is to determine the concentration of the gas-air mixture at various points of the household relative gas source. The data obtained experimentally is analyzed, which results in a formula that allows you to determine the approximate concentration of the gas-air mixture, I only know the measurement time and height relative to the ceiling to the measurement point. Also, this formula allows us to note that when choosing the installation location of the gas pollution detector, attention should be paid to the distance from the ceiling to the installation point of the device, while the distance from the wall to the installation site of the device plays a less important role when a gas leak is detected by the device.

Keywords: gas pollution detector, gas-air mixture, gas concentration, emergency shutdown, lower concentration limit of flame propagation

The article analyzes the technical condition and reliability of heat supply networks. When using the calculation and assessment of the overall reliability of pipelines and sources of heat supply. Substantiates the requirements for the reconstruction of regular pipelines.

Keywords: heat supply, reliability of the heat supply system, hydraulic calculation, reliability coefficient, dilapidation of the heat supply network