The article presents the algorithm of the step method for determining the limit loads for elastic-plastic rod systems. The development of the iterative process with the hypotheses used is given, taking into account the influence of the moment and longitudinal force on the limit state of individual sections, the lenght of the plastic deformation zones along the lenght of the rod. The advantage of the step-by-step method for determining the limit loads in rod systems in comparison with the "direct method " of A.R.Rzhanitsyn is demonstrated. The functions of forms depending on the type of section in explicit form are defined; the algorithm of tabulation of the form function is developed.

Keywords: slab and pile foundation, settlement of the building,stress-strain state,homogeneous anisotropic analog,finite element method

The paper discusses the integral indicators of the quality or level of contamination of natural waters, allowing for an assessment of their ecological status. It has been established that the criterion for the quality of treated wastewater discharged into a water body is a regulatory allowable discharge, but it is not always possible to calculate it, especially for small rivers characterized by low flow rates of the river runoff compared to the flow of wastewater. An integral indicator is proposed for assessing the level of pollution of wastewater discharged, a formula for calculating it, as well as criteria for assessing the quality of wastewater discharged according to the proposed integral indicator. The method of calculating the integral indicator is based on the assessment of the quality of wastewater discharged in terms of BOD5, dissolved oxygen, and nutrient elements. Using the wastewater discharged from the Novocherkassk wastewater treatment plant as an example, an integral indicator of the level of contamination was calculated, which made it possible to characterize the wastewater discharged as “dirty” and make a conclusion about the need for additional treatment.

Keywords: wastewater, water pollution level, integral indicator of water quality, sewage treatment facilities

The article describes the work of the lattice of the tower on the example of the support of cellular communication. The analysis of the distribution of internal forces in the elements of the lattice tower support, depending on the type of connecting grid, taking into account the direction of the wind load on the face or edge structures.

Keywords: cellular tower, steel tower, lattice tower, lattice, belt, brace, wind load, internal force, stress-strain state, stress

The article deals with the problem of imperfect design of modern bridge structures in Russia, using the example of comparing different forms of a continuous profile of bridges. Examples are given where the use of a curvilinear form would save space on the construction of bridges. A number of calculations and their analysis were carried out, as a result of which we received that the parabolic shape of the longitudinal profile of the bridge is the most efficient and economical

Keywords: construction, bridge, longitudinal profile, slope of the embankment, efficiency, efficiency, transverse profile of the embankment, length, volume

An experimental study of a transistor generator with varicap rearrangement has been carried out. A schematic diagram is given, a brief description of the construction and an experimental technique are given. As the results of the experiment are given: • frequency dependence on control voltage (modulation characteristic) • dependence of power on control voltage (parasitic amplitude modulation) • output spectrum in the 500 MHz band

Keywords: FM signal generator, voltage-controlled oscillator, modulation characteristic, output spectrum, transistor oscillator

A simulation and experimental study of a directional coupler with transformers on ferrite rings has been carried out. The operating frequency range is from 100 to 500 MHz. The directional coupler was modeled in the Microwave Office application package. An experimental study was carried out using a vector analyzer of the type "Overview-103". The frequency dependences of the working attenuation and transient attenuation are obtained. The directional coupler can be used in transmitting and measuring technology.

Keywords: Directional coupler, working attenuation, transient attenuation, decoupling, scheme, design

Plasmonic nanoparticles make it possible to localize the electromagnetic field at scales smaller than the optical wavelength. This property is useful for the application of same objects for the creation of nanodetectors, in the processes of energy conversion and storage, in the tasks of data processing and transmission. In particular, the creation of computer chips with plasmonic elements instead of traditional semiconductors will increase their performance and energy efficiency. Our main purpose is obtaining implanted in the matrix of glass the arrays of plasmonic nanoparticles with controlled optical properties. Their properties can be varied by changing the conditions of their synthesis and post-processing. Nanoparticles are created by UV-laser influence on the gold film, precipitated on the glass surface. One of the proposed methods is long-term heating at 300 ̊C of already synthesized samples. This research presents the results of the study of the effect of temperature treatment on the atomic structure of Au nanoparticles. The study of the nanoparticles atomic structure was performed by using EXAFS-spectroscopy at the Au L3-edge. EXAFS-functions were fitted by using Stepwise EXAFS fitting-code, obtained models of the NPs atomic structure were confirmed by using DFT-optimization. The fact, that the atomic structure of NPs before and afted thermal treatment is strongly dependent of the thickness of initial gold layer (6, 10 and 70nm), is established. These differencies can be explainde by different interaction between gold film & NPs and glass matryx.

Keywords: nanoparticles, Au, nanoplasmonics, EXAFS, DFT, atomic structure

The structural properties of cobalt catalysts and their active component are studied. The influence of metal oxides on the specific surface area, pore volume and size, the average crystallite size and the active surface area of the catalyst Co-Al2O3/SiO2 was studied.

Keywords: Fischer-Tropsch synthesis, synthetic hydrocarbons, catalyst, cobalt, promoter, carrier, specific surface, porous structure, catalytic activity, degree of reduction, active surface area

The physical and chemical properties of cobalt catalysts promoted by manganese oxides for the synthesis of hydrocarbons by the Fischer-Tropsch method are studied. The influence of polymorphic modifications of the alumina carrier on the specific surface area, pore volume, degree of reduction, size of cobalt crystallites,catalytic activity, dispersion degree of catalyst reduction is considered.

Keywords: Synthesis of Fischer-Tropsch, synthetic hydrocarbons, the cobalt catalyst, promoter MnO2, the carrier of Al2O3, specific surface area, the degree of recovery of the catalytic activity, dispersion, and the crystallites of cobalt

The method of local positioning of underwater vehicles by hydroacoustic system with linearly-frequency-modulated probing signals is considered. The method is based on measuring the range to the object and calculating the angles of arrival of echo signals on two or more spaced antennas. To increase energy and noise immunity signals with linear frequency modulation (LFM) are used. The scheme of towing an underwater vehicle with an acoustic beacon and the location of a hydroacoustic interferometer with two receiving antennas on a towing vessel are presented. The possibility of practical use of this method for high-precision measurement of the spatial position of an underwater towed or Autonomous vehicle relative to a surface vessel and, accordingly, the possibility of geographical reference of acoustic images and sea-bottom profilograms obtained by an underwater vehicle is experimentally shown. The results of full-scale tests of the experimental positioning system for its testing in the coastal zone of a small pond are presented. The block diagram of the local positioning equipment is presented. Examples of experimental distributions of the power module of echoes over the range are given for correlation processing of the acoustic beacon LFM signals. The paper also proposes the use of narrow-band traverse broadband parametric systems for communication between Autonomous unmanned underwater vehicles (ANPA) moving "in a flock". Describes the main specifications of the system and the experimentally measured in hydroacoustic basin of the directivity pattern of the antenna at the average rate of pumping and difference frequencies. The features of signal propagation in shallow sea are presented.

Keywords: hydroacoustic systems, side-view interferometric sonar, local positioning systems, parametric antenna, data transmission system, broadband antenna

The process of electrodeposition of the iron-nickel alloy in stationary and non-stationary electric modes is studied. The influence of periodic currents of various forms and parameters on the rate of extraction of the alloy components, its composition, and also the current efficiency of the alloy is investigated.

Keywords: iron-nickel alloy, current density, current efficiency

The problem of calculating rods for vector perturbations consisting of five components is solved: 1. kinematic transverse vibrations of the left end; 2. kinematic transverse vibrations of the right end; 3. dynamic bending moment at the left end; 4. dynamic bending moment at the right end; 5 dynamic uniformly distributed lateral load along the length of the rod. The transfer functions from each disturbance are obtained separately. Using these functions, we obtained the elements of the spectral matrix for stationary random processes, taking into account their correlation. The most common types of processes are considered: exponentially correlated random process; process with latent periodicity (with characteristic frequency); truncated white noise. The formula for obtaining the dispersion of displacement of sections is shown.

Keywords: rod, harmonic oscillations, natural frequency, kinematic disturbances, dynamic disturbances, transfer function, correlation matrix, random process, delta-correlated random process, latent periodicity, truncated white noise

The innovative development of the transport system of Russia through the organization piggyback transportation based on the technological interaction of railway and automobile transport is considered. The implementation of innovative solutions requires consideration of environmental factors, the assessment of which in this article was carried out by means of PEST Analysis. The characteristics of four groups of factors are given: political, economic, socio-cultural and technological. Their positive and negative impact on the innovation activity of the Joint Stock Company «Russian Railways» has been determined. Political and economic factors that require the development of strategic management decisions at the state level have the highest priority in terms of their influence on the introduction of piggyback transportation.

Keywords: transport, piggyback, piggyback transportation, innovative development, factor, PEST Analysis

The article describes a trend-seasonal adaptive model of the time series of the import volume of the Republic of Kazakhstan according to the quarter data in the period from 2013 to 2018. According to the obtained model, the forecast of the imports volume in the value terms for the first quarter of 2019has been made.

Keywords: Republic of Kazakhstan, import, multiplicative model, exponential smoothing, adaptive model, forecasting, trend equation

The possibility of using associative tools to solve the problem of multidimensional risk assessment is substantiated: “language of associations” for the formalized presentation of risk events and risks in the form of information objects in an associative environment; associative environment for the implementation of such assessment procedures. The approach to modeling the processes of multidimensional risk assessment based on the associative environment with its implementation on the FPGA is substantiated.

Keywords: associative environment, multidimensional risk assessment