The construction of mathematical models of objects of experimental or computer simulation is associated with the mathematical processing of experimental data. The point dependences of the output variables for the input variables obtained for them are essentially nonlinear, piecewise, sometimes discontinuous. Approximation of such dependencies using polynomial expansions or spline functions is both difficult and involves large errors. A fundamentally new solution to this problem was proposed in the article. This method, called the "Cut-Glue" approximation method, is based on the partitioning of the modeled dependence into sections, the approximation of each section by polynomial dependencies, the multiplicative "excision" from each dependence of the fragments along the boundaries of the plot and the additive "gluing" them together into a single function - the model of the approximated dependence . The analyticity property of the resulting function allows to study the model and use it in models of vehicle dynamics. One of the stages of the "Cut-Glue" method is the "Glue" process - the additive "gluing" of fragments into a single function. For this, an auxiliary multiplicative function is used. The function of this function includes the steepness of the pulse fronts. In this paper, a developed modification of the method of burrowing particles is used in the problem of research and suboptimization of this parameter. As a test bench of the developed algorithm developed a special software tool.

Keywords: optimization, approximation, mathematical model, experimental data, heuristic methods, the method of burrowing particles

The article considers the application of a modified two-stage genetic algorithm to solve the traveling salesman problem. The traveling salesman problem is a classical combinatorial optimization problem known since 1930. The traveling salesman problem is NP-complex. With the number of cities 66 or more, it is impossible to solve it by exhaustive search. To test the proposed approach to the solution, we consider a graph with 51 vertices from the package TSP_LIB. At the first stage, a modified Goldberg model with small parameter values works to obtain the first generation of the second stage with better performance than the random formation of individuals. The second stage works with increased values of genetic algorithm parameters. These values vary from experiment to experiment, the results of which are presented in diagrams. Also, the results of the two-stage algorithm are compared with the results of the one-stage algorithm. A modified Goldberg model of the genetic algorithm is used. The genetic algorithm uses a waypoint representation of a traveling salesman's route with a two-point ordered crossover and a "greedy" mutation. The experimental results showed the effectiveness of the proposed approach. The modified two-stage algorithm allows to obtain a solution close to the optimal one.

Keywords: traveling salesman problem, genetic algorithm, Goldberg model, crossover, mutation, individual, route, Hamiltonian cycle, distance matrix

The paper presents a method for decomposition of a complex dynamic system with a network architecture based on the Crohn's diakoptic approach. The proposed method is aimed at the allocation of independent network segments, the removal of which from the general structure will not affect the overall performance of the system. Segments are formed as simple paths in the graph model of the system with the least weight of the incident edges and checking the condition for maintaining the product flow balance in the application to the transport task. In general, the decomposition method presented allows us to divide a complex technical object of the network architecture into subsystems, simplifying the process of analysis and management. In the case when the common control task and the dynamics of interaction of subsystems allow the system to be broken up into unconnected segments, or to limit interaction over certain lines, the method allows reducing the load on the transmitting elements of the system.

Keywords: decomposition, complex dynamic system, network, grapho-analytical method, network segmentation, diakoptics, load reduction

In this article, a prototype of a multichannel digital ammeter will be considered. The structural scheme and algorithm of the program for the microcontroller is presented.

Keywords: ammeter, digital ammeter, multichannel digital ammeter, prototype ammeter, Hall sensor, Hall effect

The issues of evaluation features of reinforced concrete structures of protective shells of the NP-1000 project of nuclear power plants with a the water-water energetic reacto (VVER-1000) during the construction period are considered. The results of measurements of the strength characteristics of concrete, the thickness of the protective layer of reinforcement and the parameters of cracks made in the framework of the instrumental survey are given. The conducted instrumental survey allowed us to obtain fairly complete and reliable information about the parameters of the elements of the protective pressure-tight shell to perform calculations of the stress-strain state of the shell.

Keywords: protective pressure-tight shell, methods of non-destructive testing, deformations, displacements, cracks, strength of concrete

The manuscript describes the design of a simple LED illuminator for fluorescence microscopy of biological objects. As the light source, high-brightness semiconductor diodes were chosen that provide stable low-noise light. This distinguishes them from traditional light sources, such as mercury lamps. The presented light source can be used to record low-amplitude fluorescent signals in studies of excitable cells performed using calcium or potential-sensitive dyes. The illuminator is made of inexpensive, easily accessible components.

Keywords: high-brightness LEDs, illuminator, fluorescence, microscopy

The issue of improving the cost coverage of the construction company is considered. The authors consider the issues of break-even production. The article deals with three main sources of losses of a construction company. Measures to eliminate them are proposed

Keywords: organization of construction; economy of construction, break-even production

The article proposes an algorithm for the functioning of adaptive motion control systems of a group of mobile transport robots in conditions of uncertainty. The algorithm was developed based on the Markov method of identification and the method of analytical synthesis of systems with control by output and effects. The adaptive control system in which this algorithm is used has direct quality indicators not worse than those specified. The proposed algorithm can be used to create control systems for technical objects of various types, with previously unknown mathematical models.

Keywords: mobile robot, group, uncertainty, identification, Markov parameter, control by output and effects, system

The article describes the concept of the digital gas sensors for toxic and flammable gases used in portable gas analyzers and stationary systems for dangerous objects monitoring. The results of the development of the low-power digital gas sensor for determining the concentration of carbon monoxide are described. The structure of the analog sensitive element, as well as its sensitivity to various gases and ambient temperature, is considered. A structural and schematic solution of a digital gas sensor using operational amplifiers and a miniature microcontroller is presented. The algorithm of firmware of the microcontroller is considered, as well as the calibration process.

Keywords: Digital gas sensor, toxic gas, gas converter, carbon monoxide, gas analyzer, monitoring system, calibration process, gas generator

The problem of reconstruction of architectural structures of Central Asia is studied. The stages and periodization of the ensemble construction are considered. The basic design solutions of buildings are determined

Keywords: organization of construction; economy of construction, history of the construction industry

Beams are structural elements subjected to bending loads transverse to their longitudinal axis. For steel beams, which compressed flange is not laterally restrained, checking loss of overall stability is often authoritative in determining their section. In engineering practice are known various approaches to verify the assurance of the steel beam against lateral-torsional buckling. In this article the attention is focused to the methods and their characteristics, described in actual version of the European standard EN1993-1-1.

Keywords: lateral-torsional buckling, steel beams, critical bending force, FEA

This work represents the third article within the cycle devoted to the peculiarities of the analysis of the situations in geopolitically unstable zones of the modern world. This time the author focuses on the second stage of the mentioned scientific procedure. He assumes the analysis of the dynamics of such zones (regions) as multifactorial combinatorics, with the dominance of the conflict nature of interstate relations and the key role (in some cases) of non-regional players. An attempt is made to present unstable regions and the same kind of limitrophic zones as a combination and overlapping of the force fields of a different nature.

Keywords: modern world, geopolitically unstable zones, separation belts, limitrophic zones, interstate relations, multilateral and vertically organized, conflictness, asymmetrical conflits, international mediation, force fields

The article is devoted to the approach to the development and design of effective dust collectors for the aspiration systems of the construction industry. It was proposed and implemented the study of the particle shape factors that determine the hydrodynamic features of gas flow around dust particles, for example, in the aspiration schemes, which are most spread and applied in the construction industry using the results of complex analysis of variance it this article. It was presented results of implementation hydrodynamic criteria in the output function of the analysis. The values’ meanings of the particle shape factors of the dusts’ particles were gained and obtained at the final stage of experiment. It was obtained regressions for particle shape factors as functions of hydrodynamic criteria. It was proposed dependences to clarify the particle sedimentation-growth velocities taking into account the influence of the particle shape factors of the studied dust samples. It was allowed possibility to assess and obtain ranges of changes in the values’ meanings of particle shape factors. It was obtained more reliable results for determining the sedimentation values’ velocities of dust particle as a determining result of complex analysis of variance of particles also. The research results allow the development and design of dust collecting devices for cleaning emissions in dust removal systems of the aspiration schemes of the construction industry. These dust kinds of collector provides a significant reduction in dust leakage out from dust removal systems of the aspiration. This way become one of the highly effective prevents polluting ways that allows to improve environmental safety of the construction industry.

Keywords: Dust, building material, dust collector, cleaning, leakage, analysis of variance, velocity, sedimentation, criterion, emission, atmosphere, dust removal, aspiration

When organizing work on the territory of sanitary protection zones, it is necessary to take into account that the SPZ is already a territory with elevated levels of exposure, which may require the use of additional means of individual and collective protection. Meteorological parameters are important factors affecting the extent of the impact of the work on human health. The article presents a comparative analysis of the concentration of suspended substances in the workplace, depending on meteorological parameters.

Keywords: sanitary protection zone, hazard class, industrial enterprise, construction, reconstruction, ecology, atmosphere, labor protection, non-stationary workplace

In the article, a numerical study of the heat sink with a change in the aggregate state of the oil is carried out. Simulation was carried out in Ansys Fluent CAD for two modes, static - with constant heating of the oil at 340K and dynamic, at which the heating temperature varied with time from 340K to 270K. Heat transfer in the event of a change in the aggregate state of a substance is widely used in cases where it is necessary to achieve the maximum efficiency of heat exchange. In this case, the energy is expended on the phase transition of the substance, for example, to evaporation from the liquid phase. The advantage of the heat-sink design described in this work is a rather high rate of heat transfer, greater resistance to various influences, including mechanical ones, which is primarily ensured by the simplicity of construction, eliminating the drawbacks of classical designs, which are cumbersome (the presence of an external cooling circuit ) and the limited rate of heat transfer.

Keywords: heat dissipation, numerical methods, aggregate state, computational experiment, heat exchange efficiency