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The article presents signals processing method for fiber-optic sensors with tilted Bragg grating. Developed technique is based on the analysis of signals output spectrum to capture Fourier-images in the area. The main idea of the being offered method is in using sensitive tilted fiber Bragg grating fiber-optic sensors. The given sensor is insensitive to any influence in multimode fibers and other parts of the device. Devices, based on such principles, do not need recalibration after switching on and further operation. There is presented the sensor parameters optimization on the basis of numerical modeling. Outcomes of numerical modeling permitted to broaden the domain of internal parameters of sensor’s sustainable operation.

In this paper, an LED screen with ultra-low power consumption is developed. The work proposes methods for modeling mechanical and electronic systems. The combination of these scientific works gives us an opportunity to reduce power consumption. Spatial-mechanical sweep is developed, which allows to refuse decoding circuits, which in turn consume 35-40% of the total power consumption. We studied the setup of SDRAM controller for reading video data stored in memory or entering data into memory, and developed a code for reading data from the controller memory and outputting it to the data bus on demand of the output device. The results of this study can be widely used by the system for the integrated operation of the evacuation information system in training mode in order to train and mobilize personnel responsible for evacuation, as well as to keep all information and communication resources in readiness.

The study describes sensors with an inclined grid de-signed to monitor the condition of structures installed on the bridge. The aim of the study is to study the possi-bility of using the developed sensors with an inclined grid to monitor the condition of structures by checking the deformation of various parts of bridges under highway loads, as well as comparing the characteristics of sensors with an inclined grid with conventional Bragg sensors. In this paper, experimental observations show that the results of using sensors with an inclined grid are in excellent agreement with the results obtained using conventional Bragg sensors. Also, a change in the wavelength of the VBR was detected and a comparison of the deformation characteristics for measuring tem-perature without deformation and the VBR for measur-ing deformation characteristics on a sensitive Bragg sensor for 700 seconds.

In the work herein there was developed numerical analysis of forming uniform fiber Bragg gratings, using phase mask. There was developed method of recording Bragg grating, using uniform phase mask, which is characterized with a fact, that it consists of ultraviolet excimer laser, output laser light beam, directed to the system of mobile diaphragms with regulated gap between them and located behind the system of mobile diaphragms of uniform phase mask, after which there is a photosensitive multimode optical fiber with tilted Bragg grating. In the research there was applied diffraction theory to analyze intensity distribution in the fiber core during fabricating fiber Bragg grating (FBG), using uniform phase mask. There was calculated averaged distribution of diffraction field in the fiber core as a function of optic fiber position. Outcomes show, that in case of fabricating uniform FBG, averaged intensity field profile, as well, refraction index of optical fiber position behind phase mask is decreased for average intensity distribution in the fiber core along with increase of its diameter.

The article herein considers testing and distant health monitoring of bridge structure in Kazakhstan, Almaty oblast, at river Issyk. Bridge on river Issyk represents a deck type construction with total length of 70 meters and width of 6 meters. Superstructure consists of 10-inch monolithic reinforced concrete plate and leans against at prestrained piled bends, each of which consists of 5 piles. Bragg smart tilted grating fiber-optic sensor for distant health monitoring is embedded beneath the bridge. There have been conducted static and dynamic bridge testing with loaded trucks and automobiles. The sensor was switched on to data collection system, constantly installed in-situ. Collected data, as well, analytical investigations prove, that current bridges specifications are conservative. Technology, having been developed in this work’s framework, will allow fulfill practical, economically effective and reliable systemic technical maintenance of bridge structures, and research will give unique possibility for future growth of the technology in Almaty oblast and in other regions of Kazakhstan.

Road infrastructure is a key public asset because it benefits the social and economic development of any country. It plays an important role for the development of the industrial complex, the production sector and the road surfaces of transport roads should be of high quality, have a long service life. Road infrastructure, as well as all infrastructure, requires preservation, maintenance and repair. There are special requirements for the roadway that must be observed during construction or repair. This article is devoted to a detailed study of the use of fiber optics sensors (FOS) based on the fiber Bragg grating (FBG) for road surface monitoring. Such a fiber sensor consisting of a fiber Bragg grid and a pair of grids can offer the possibility of simultaneous measurement of deformation and temperature for monitoring the pavement. Temperature and deformation measurements were carried out by installing a sensor on the surface of a made asphalt sample. The built-in fiber sensor based on FBG provides important information about how the pavement structure can withstand the load, subsidence of soil, timely implement road safety and stability measures evaluate and predict the service life of the pavement. The results of the study showed that the synchronicity, repeatability and linearity of the characteristics of the fiber sensor are excellent. The difference between the experimental and theoretical results is about 7%. Thus, based on the results of the obtained data, the fiber sensor on the FBG can be used for monitoring, designing road surfaces and in general transport infrastructure.

The main goal of the work is to create the optimal emergency evacuation plan in general education institutions according to the schedule at a certain time. The work developed an information model of the evacuation system, taking into account the schedule of classes and classrooms. The methodology of the system approach, which ensures the compatibility of heterogeneous devices to find an operationally optimal evacuation plan in real time, was developed. A conceptual scheme of an evacuation system using heterogeneous sources of receiving and transmitting information about emergencies is proposed. Determined the input and output sources of receiving and transmitting information about the number of people in the building. Developed software for the rapid and most effective evacuation of people from the educational institution and can be used for other types of buildings. The importance of this work is the creation of an integrated evacuation information system based on mathematical modeling of multi-criteria optimization problem of flow distribution and design, construction technology receiving and transmitting data and information notification systems for the selected type of building. in order to adopt an operational evacuation plan. The results of this paper allow the systematic organization of evacuation training, preparing resources so that in the event of an emergency it is possible to quickly respond and conduct the evacuation process to avoid major consequences. The use of information technology greatly increases the efficiency of evacuation systems, so the development of new integrated and intelligent info-communication approaches to solve the problem of evacuation is currently very relevant

In the article there have been considered the issues of mathematical and computer modeling of fiber Bragg granting’s, using the method of transfer matrix. Method of transfer matrix allows specify the spectral characteristics of optical components, based on theory of bound modes and matrix description of electromagnetic wave, passing through optic fiber. There have been analyzed fiber Bragg granting’s with different lengths in accordance with spectral characteristics, such as, transmittance and reflection spectra. As well, there was carried out the experiment with influence of various parameters at fiber Bragg granting’s spectral characteristics. Fiber Bragg granting’s spectral characteristics were studied and optimal grating parameters were selected for developing the fiber-optic sensors, based on fiber Bragg granting’s. Developed and studied a computer model of flow-diagram of communication modes theory and Transfer Matrix Method. From the studied model it might be noticed, that in MATLAB software, selected for modeling, were formed for implementation into the MATLAB code. As well, in MATLAB software there were used fiber Bragg granting’s principal features and selected for studying influence of external factors, such as deformation, strain and temperature at FBG sensor’s reflection spectrum.

In modern conditions, due to the vastness of the territory of Kazakhstan, with a certain probability, natural disasters such as earthquakes, floods, avalanches, as well as accidents, destruction of buildings, epidemics, release of chemical toxic substances at industrial enterprises, fires in educational and medical institutions are possible, which justifies the relevance of modern methods and technologies for solving the problem of evacuation. The peculiarity of this work lies in the formation of an integrated approach for organizing the evacuation process both in peacetime as training for the event of an emergency situation (emergency), and in the event of the emergency itself. A conceptual diagram of an evacuation system is proposed that uses heterogeneous sources for receiving and transmitting information about the onset of an emergency. The input and output sources for receiving and transmitting information about the number of people in the building are determined. The main purpose of the system is to form an operational real-time evacuation plan. This work is the result of a phased implementation of an integrated evacuation system, which consists in building a mathematical model and a method for solving the problem of maximum flow in the network. A mathematical model has been developed for the optimal flow distribution along the Grindshiels network with the analysis of the flow formation and the characteristics of people’s motion in enclosed spaces. A game-theoretic approach and mathematical methods of the theory of hydraulic networks for finding an equilibrium state in flow-distribution networks have been developed. An algorithm for solving the evacuation problem using the graph approach is proposed. The results of this paper make it possible to systematically organize training evacuations, prepare resources, train the personnel responsible for evacuation in order to quickly respond in an emergency and carry out the evacuation process in order to avoid major consequences.

The paper herein considers the study of convective heat transfer in flat plate solar collectors, as it is seen from the analysis on research of the heat transfer by a circular and flat tubes upon conforming the forced and free convections, placed vertically or horizontally with various liquid flow directions. There have been obtained Nusselt criterion dependencies in circular and flat pipes, which shows that corresponding equations allow defining the heat transfer intensity for all fluids with appropriate accuracy. As well there has been studied Prandtl criterion for fluids, which plays an important role in points spacing as regard to the curve. In each case the lines are with a tip 1/3, as in the research herein only the laminar conditions have been considered. The article herein considers the pilot tests based on tubular solar collectors with an absorbing shield. The aim of the experiment thereof is the research of thermal properties of tubular solar collector for producing hot water.

In the result of carried out researches with simulation usage there have been obtained the dependence of the spectral reflectivity characteristics of Bragg gratings on the grating length and on the local changes of the fiber core refraction index, as well, that the spectral reflectivity thereof increases along with the grating length enlargement. Outcomes of mathematical modeling in MATLAB medium and carried out analysis of the light emission in the Bragg grating fiber structure clearly denote the possibility of time impulses control magnitudes extension. In the end it has been concluded, that we can precisely control the dispersive claddings in the fiber-optical line through appropriate selection of the Bragg fiber gratings apodization parameters.

In the article herein, we consider the theoretical prerequisites of the solar collector accumulatorenergy saving sources One of the solar collector-accumulator main peculiarities is in the fact that it works under coldtemperatures or in the dull days due to design features. There was proposed a new method of the flat solar collectorusing modern materials, thanks to which the collector’s performance upgrades and its cost reduces. Collector’sefficiency is reached owing to the proposed construction, which consists of transparent thermally insulated body,semitransparent color, absorber’s capacity, thermoelectrical heater. Thermoelectrical heater is a main feature, whichis used for water heating. Proposed new method of thermoelectric heating is theoretically substantiated and consistsin adjusting the thermoelectric power to changing the stress in appropriate range, as well, to changing the resistanceof thermoelectric heating elements through switching from sequential circuit to parallel one. The new electric schemehas been offered as a controlled thermoelectric heater inside the collector. Solar collector-accumulator researches andworkings in the mode of electric heating show, that the computation of water heater average value from 5 до 9%confirms the suggestion about the theoretical outcomes of the solar collector accumulator work. There have beenselected thermoelectric capacities values as 1,5, 3,0 and 4,5 kW, liquid optimal temperature (60 oС) has been reachedfor 3 hours at capacities 3,0 and 4,5 kW, it is a good result for a cold season or dull days. Economic analysis of usingthe proposed thermoelectric capacity inside the solar collector is not considered in the work herein and remained forfurther studying.

The focus of this research is on the upgrade of the electromyographic system of diagnosing back pain. Back pain is a common ailment that affects people of different classes and differs in its intensity. The evaluation of the condition of the back muscles is carried out according to the results of an electromyographic examination during physical exercise. Electromyographic results are strongly correlated with the degree of tension and flexion of the muscle. The quality of the physical exercise by the patient can be determined by the presence of pain or fear of pain. In this regard, it is proposed to supplement the electromyographic complex with blocks of control of the level of pain, degree of flexion of the back muscles, and sound stimulus to maintain maximal back flexion

This article discusses the mathematical models of the individual structures and modes of operation of a double-circuit solar collector with thermo siphon circulation. To perform this task, we considered a new design of a flat solar collector with thermo siphon circulation, in which the heat transfer coefficient was increased by eliminating additional partitions between the panel and thermal insulation. The efficiency of the solar collector is achieved due to the presence of the metering tank and the heat pump in the tank, where the condenser and evaporator are made in the form of a “spiral in a spiral” type heat exchanger, and the heat exchanger pipelines are placed one above the other, which allows increasing the area and intensity of heat exchange. The result of this work is a theoretical and mathematical analysis of the unsteady thermal regime of flat solar collectors on the modes of operation under consideration. Based on the results of the analysis, it is possible to optimize individual structural elements, as well as to predict the thermal regime and select alternative solutions for the design of flat solar collectors and the choice of operating modes.

In the research herein, we have considered the thermal and hydraulic analysis of transfer media motion mode in the flat solar collector. We have substantiated the thermal and hydraulic parameters of the flat plate solar collector. Heat absorbing flat solar collector tubes hydraulic analysis has shown, that using the heat transfer standard size there might be located the pipeline, the length of which 2.5 times more than of the collector's body, sufficiently increasing at that insolation time on the transfer media.

The work is devoted to the modern method of diagnosing skin diseases - video dermoscopy in the ultraviolet spectrum. The main features of the method are considered. The features of image processing and analysis for HC-video dermatoscopy are proposed for consideration. The main stages of processing HC-video dermoscopic images are considered. The main emphasis is placed on the methods of automated segmentation of HC-videodermoscopic images and the analysis of the errors that arise in this case. The stages of preliminary and post-processing of UVvideodermoscopic images are examined in detail. The main aspects of the automated analysis of dermoscopic image processing and the prospects of using such systems in medical practice are considered.

Among the various characteristics of infrared radiation, the degree of polarization is not often used in radiation analysis. The main reason is that polarization is less informative characteristic compared to others for most practical tasks. Also obtaining polarized radiation in infrared spectrum is relative complex and expensive act. In some cases, such as remote sensing, the improvement of spatial, radiometric and spectral resolution approaches it’s physical limit. It becomes relevant to obtain additional information of a different nature, such as polarization information. Modern infrared radiation polarizers based on diffraction gratings are quite expensive. The article explores the possibility of creating infrared polarizers based on a planeparallel plate, to which radiation falls at an Brewster angle. It is shown that the polarizer operating on transmittance will be more efficient than reflecting radiation polarizer, since it does not deviate the optical axis by a significant angle. Such a polarizer provides a polarization degree of 90% and a transmittance of about 50%.

The present article considers the experimental tests on the tubular solar collector with absorbing shield. Aim of the experiment thereof is research of thermal characteristics of tubular solar collector for producing hot water. During the experiment there have been specified the thermal performance, solar installation circulation, water heating dynamics, which maintain water heating at the expense of solar and electric power combined use.