The journal "Electronic and Acoustic Engineering" is a scientific edition of Ukraine in the field of engineering sciences. The journal publishes original articles and review of results of the study of the basic problems of electronic equipment (vacuum, quantum and solid-state electronics, physical and technological aspects of the production of discrete devices and integrated circuits), communications (engineering, telecommunication and computers systems and networks, wireless devices and telecommunications, principles networks, Internet); reports of scientific conferences, bibliographic reviews. The journal launched in 2017 by the Electronics Faculty of Igor Sikorsky KPI
National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute"
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Automatic musical genre recognition using deep convolutional neural networks
For the long time in computer vision and digital signal processing manually developed algorithms and filters were used. With the development of computers technics and constantly growing amount of available data samples, these algorithms became less accurate than modern machine learning approaches. The idea behind them is to construct useful representations based on data itself rather than on expert knowledge. Such approach allows machine learning algorithms to choose for themselves which parts of data more important. Today machine learning is successfully applied in such tasks as image recognition in Google image search and speech recognition in Google Now, Siri, Cortana. Nowadays best approaches are built upon different variations of neural network algorithms. One of the fields, where machine learning are successfully applied is music information retrieval, where musical genres classification is one of the main tasks and solving it efficiently can help automatically organize large collections of musical data which are available for now. As music genre aggregates a lot of song information, model for calculating music song similarities based on audio information can possibly be built on proposed model. In this article, the algorithms for automatic music genre recognition are discussed and usage of deep convolutional neural networks is proposed for this task. The network’s architecture is described and its quality evaluated on real-world data. In this work GTZAN dataset is used and classification problem for four and ten genres classification was examined using mel-frequency cepstral coefficients and waveform as features. The quality of proposed algorithm was evaluated on hold-out set for four and ten different genres and compared to using restricted Boltzmann machines for four genres classification. The resulting accuracy for our genres classification task is 76%, which is about 15% better than restricted Boltzmann machine approach. Though model overfits strongly on rather small dataset it can be fixed by using larger amount of data. The main differences between proposed neural network architecture and traditional convolutional neural networks are gated activations, dilated convolutions and residual connections. Gated activations allow the network to additionally weight and inhibit importance of intermediate features like it is done in recurrent neural networks. Dilated convolutions allow increasing receptive field of network’s filters while maintaining small number of trainable parameters. Residual connections are proven to be vital feature for very deep neural networks to prevent gradient degrading and neural networks with residual connections yields best classifications accuracy for image classifications task for now. The proposed neural network is used to classify musical genres, based on pure waveform or mel-frequency cepstral coefficients, which are well known to be good sound representation for speech recognition task. Ref. 11, fig. 3, tabl. 2.
Telecommunications and information security
Copyright (c) 2018 Ярослав Юрійович Дорогий, Василь Васильович Цуркан, Олександр С. Хапілін (Автор) https://creativecommons.org/licenses/by-nc/4.0
Consideration of most important parameters and selection of the laser for transmitting module of space laser communication system
Laser communications through optical fibers move tens of terabits of data every second between cities and across oceans. But for the majority of Earth’s surface, where running fiber is impractical physically or financially, communication satellites in space provide connectivity—to remote ground users and also to mobile platforms such as aircraft, ships and even other satellites. These links rely on radio-frequency communications, which, while reliable, are orders of magnitude slower in moving data than optical fiber links, and have issues related to antenna footprint, power requirements and limited available spectrum. Also the requirements of a number of future planned space missions in low earth orbit, mainly in the field of earth observation, ask for high data rate capability to a geostationary data relay satellite. In the field of communication satellites, increasing traffic demand requires the use of inter—satellite links to conserve bandwidth and improve link quality by shorter transmission delays. The potential for the laser to overcome these issues in space was realized soon after its invention. Recent and upcoming deployments of satellite laser communication systems are bringing Internet-like speeds for data transmission in space. The result could be a revolution in communication, both on Earth and across the solar system. Laser communications uses collimated laser beams to transmit information at high data rates in the multigigabit regime, preventing interference problems and exhaustion of radio-frequency bandwidths. Laser transmitters, at wavelengths some 10,000 times shorter than RF waves, result in beams that are far narrower for the same unit aperture size—providing more concentrated communications power at the receiver with lower required transmitted power from smaller, lighter apertures. The upshot is a lower size, weight and power requirement for transmit and receive apertures of a laser communications terminal. Perhaps just as important, there is almost no spatial overlap among various users, so the optical spectrum of free-space optical communication is at present unregulated — a significant advantage for space-based users. In this article parameters of the transmitting module of laser cosmic space communication system are considered. These parameters require special attention, because they have the greatest influence on the quality of data transmission in such system. The laser with the more suitable parameters for applying it in the transmitter has been selected based on this information. Such parameters of the laser beam as sufficiently low divergence, high energy efficiency, high impulse density are very important for information transmission over long distances through laser energy. Since delivery of cargo into space is very expensive, before launching any device in space is important to be sure about effective use of its components so transmitting module of space communication system must be durable, energy efficient, must have a relatively small weight and size. The laser used in system have great influence on these parameters. Ref. 12, fig. 2, tabl. 1.
Copyright (c) 2018 Іван Анатолійович Голуб, Станіслав Володимирович Денбновецький (Автор) https://creativecommons.org/licenses/by-nc/4.0
Human inner ear cochlea in a long line modeling
In this paper was presented a little overview of the study of the cochlea of the human inner ear. More than 6% of the people have hearing problems. Early diagnosis of hearing disorders allows to prevent deterioration or loss of hearing. Researching the cochlea construction occurres for centuries. The basic theories of the transmission and transformation acoustic signal in the cochlea were analyzed such as Helmholtz theory, Rutherford’s "telephone theory", Evald and Harst standing waves theories and Bekesy’s theory. The last one theory is the most proven theory, despite this it has a lot of questions, which is need to be answered. Also it was shown general methods of modeling human cochlea such as hydromechanical and electric models. Hydromechanical modeling show that there are resonant processes on the basilar membrane while applying sinusoidal excitation signal to the membrane’s input window. The most informative data about the attenuation of the excitation signal during running wave transmission can be obtained using electrical modeling. This models give a clear idea about the transfer and transformation of the acoustic signal in cochlea. It was analyzed the features of modeling human inner ear cochlea in a long line and spiral presentation. We considered the cochlea curvature influence on the hearing in wave propagation along the channel. The functional meaning of cochlea coils attracted researchers in different areas and at different times. For a long time it was believed that spiral form does not affect on hearing and it was showed by physical and mathematical models However statistics indicate a strong correlation between the number of spiral coils and low frequency hearing thresholds. Wave energy remains constant while waves of basilar membrane passing along the cochlea channel due to slow resize of cochlea including curvature. Since the wave energy is constant, it can be argued that the average value of the cross-section is also constant. The curvature creates a radial gradient in liquid pressure. The cochlea’s curvature increases the radial displacement in the basilar membrane caused by redistribution of wave energy density across the width of the channel. Due to difficulties in modeling cochlea considering all the parameters in a spiral form the modeling was presented like a long line. In this work is showed an idealized schematic representation of the cochlea of the human inner ear. Ref. 17, fig. 3.
Copyright (c) 2018 Сергій Анатолійович Найда, Валерія В. Безродна (Автор) https://creativecommons.org/licenses/by-nc/4.0
The principle of preemptive control in Smart Grid
In presented paper the main principles that influence the formation, existence and development of socio-technical structure of society are revealed. The conditions for preemptive control applying to Smart Grid energy and information platform are determined. The technical level of implementation of energy and information platforms in Smart Grid depends on the covered space, climatic conditions, quantity and density of the population. The community of many individuals who are both the owners and users of the separate technical components of distributed generation systems poses both to individual members of the community and to the community as a whole questions, on the solution of which depends not only on the wellbeing but also the existence of a new socio-technical system. Structuring a community is based on the formation of socio-technical groups, the dual structure of which determines the need for new approaches to system control. Formation, development and structuring of the community are determined by three components: physical and technical properties of energy and information platforms; social properties of individual; cognitive, psychological and emotional qualities of individuals who have access to energy and information tools. It is shown that sufficient conditions for the system operation as a whole are determined by the presence of a distributed in time and space control system that combines and implements three main principles of control: centralized, decentralized and combined. Three mentioned principles are based on: Heisenberg's uncertainty principle that indicates the limited accuracy of the decision making and the possibility of error accumulation during the prolonged operation; principle of synergistic development; principle of cognitive control. In distributed generation systems these principles determine the logic of construction and operation of general control. Five hierarchy levels of control in Smart Grid are described and control objects and strategies for each level are given. It is shown that preemptive control should be situated on the highest (fifth) level. If in the process of operation the system is approaching a critical point, preemptive control implements advanced way to eliminate the threat of destruction of the system and the localization of hazardous technical objects. Six main steps on changing the current state of the system are described. When implementing the preemptive control to maintain the system stability it is necessary to pay attention to the theory of Robert Adams, according to which the "arm race" is one of the most important factors in stability ensuring. The main personal qualities, which determines the level of influence of the actions of individuals on the state of the system are listed. The formulas are given that allow by estimating the rate of increments of the magnitude of emotion to predict the appearance of critical points when making decisions on changing the system structure or tariffs. It is shown that preemptive control, as the system of the highest hierarchy level: blocks the threatening nodes; changes the structure of the system if necessary; passes to other control tasks. It is shown that the implementation of preemptive control at all levels of the hierarchy allows to ensure the necessary freedom of movement of the social and technical structure of society on the basis of the Smart Grid with ensuring its positive social development and blocking the negative impacts of individuals or social groups. Ref. 15, tabl. 1.
Copyright (c) 2018 Катерина Сергіївна Осипенко, Валерій Якович Жуйков (Автор) https://creativecommons.org/licenses/by-nc/4.0
The use of a p-q theory for controlling a three-phase active power line conditioner
This paper is devoted to development of theoretical positions and experimental research aimed at further development of the theory of calculating the three-phase systems for reactive power compensation and harmonic distortion. Simplified scheme of a three-phase parallel type active power line conditioner, connected to the system 3-phase network-nonlinear load are presented. The work of a parallel-type three-phase active power line conditioner with using a p-q theory is investigated in this paper. A method is described that allows one to move from the abc to the αβ0 coordinate system with using a transition matrix. Expressions of the reference with taking into account the condition of ensuring a constant voltage of the storage capacity are obtained. Defined expressions needed to calculate the power consumed by the compensator for stabilizing the voltage at the capacitive storage with using a Clark conversion. A Matlab/Simulink model is constructed with a control system synthesized on the basis of the p-q theory. With the help of the developed model evaluated the quality of the filtration current curve. The diagrams of the load current, the estimated current of the compensator and the resulting current of system consumption for one phase presented. The harmonic composition of the current consumed from the network and the effect of using a filter-compensating converter are analyzed. Ref. 11, fig. 5.
Copyright (c) 2018 Дмитро Анатолійович Миколаєць, Максим Олексійович Мацюк (Автор) https://creativecommons.org/licenses/by-nc/4.0
Frequency band limited musical signals objective and subjective quality assessment
In this paper, analysis of features of some objective indicators of the audio signals quality, such as the segmental signal-to-noise ratio, log-spectral distortions and bark-spectral distortions, for estimating the quality of musical signals with a limited frequency band has been presented. It has been shown that the interpolation of the test signals allows increasing the reliability of the evaluation using segmental signal-to-noise ratio and log-spectral distortions indices. Results of objective and subjective quality estimation of speech signals distorted due to bandwidth limitation are compared in the earlier work by means of correlation coefficients calculation and construction of correspondence maps. It was assumed that speech signals occupy a frequency band not exceeding 11 kHz. Meanwhile for high-quality musical signal reproduction, a much wider range of frequencies up to 20 kHz is required. In this regard, it is interesting to study the relevance of subjective and objective indicators of quality for musical signals, which is the main purpose of this work. Experimental studies used 16 second fragments of musical compositions, categories "pop" and "classical" music. The file format is WAVE with a sampling rate of 44.1 kHz. Increasing of the sampling frequency by means of their interpolation has a beneficial effect on segmental signal-to-noise ratio estimates allowing to eliminate illogical violations of the monotonicity of the segmental signal-to-noise ratio dependence on the frequency bandwidth Studies have shown that one of the reasons for the monotonicity violation in the log-spectral distortions dependence is the imperfect frequency response rectangularity of used low-pass filters. Indeed, the log-spectral distortions dependences are monotonic when filtering is realized in the frequency domain by means of ideal rectangular frequency response. It should be noted that when using low-pass filters with rectangular frequency response, the log-spectral distortions value also turned out to be dependent on sampling frequency selection as in the case of non-ideal low-pass filters. The reasons for this phenomenon are worth exploring in the future. Although 30 listeners took part in subjective trials, this quantity can hardly be considered as representative, and further its volume should be increased. Note in addition that quantity of the tested music fragments was very limited. Taking into account the pointed features, the results obtained in this paper should be regarded as preliminary. Obtained results of objective evaluation are compared with the quality assessments obtained by subjective testing. Ref. 9, fig. 3.
Copyright (c) 2018 Ігор Валерійович Котвіцький, Андрій Оса (Автор) https://creativecommons.org/licenses/by-nc/4.0
Designing of sound intensity measuring simulator for bearing tasks
Work is devoted to problems of simulation devices and methods of acoustic measurements. The problem of measuring the sound intensity as one of the most important characteristics of the sound field by using only pressure recievers. According to the algorithm determining the intensity measurement device simulation performed based additive and multiplicative operations. With instrumental laboratory Lab View software model received intensy-metr simulator software and mobile device detection air or underwater noice-radiation objects. The main reason for using Lab View is that this tool-graphic package, oriented to object programming, essentially provides the construction of an algorithm for the desired procedure for the device to be implemented. At the same time, the user interface is simple and accessible, it is possible to use a wide range of input data and a variety of indicator and recording devices. In this case, the program body in the LabVIEW<sup®environment is created in the form of a graphical diagram reflecting the sequence of mathematical operations that determine the operating principle of the device. Thus, the chain: "mathematical expression - block diagram - program" is practically realized by objects of the program algorithm. A simulator has been developed that allows not only to measure the intensity of acoustic perturbation of the working medium in true and relative units, but also to ensure the operation of the device for detecting a useful signal against the background of isotropic sound noise represented by white noise. Simulation of the receiving acoustic device was carried out on the basis of a model combining the capabilities of pressure receivers and receivers of oscillation speed. In this case, the number of pressure receptacles can vary - from two to three. In the topic there is a variant of the receiving device, consisting of three pressure receptacles. The resulting software algorithm, formally, contains four groups of device-tools, namely: devices for simulating input signals; devices for the formation of signals of difference, sum and phase shift; filtering devices that provide the formation of a working frequency band and filtering devices that realize the principle of the parity-type spectrum analyzer; group of indicators. The obtained results are proposed to be considered as the initial ones for the creation of simulators of air and underwater sound-direction findinging on the basis of combined receivers. Ref. 9, fig. 4.
Copyright (c) 2018 Андрій Віталійович Козак, Пилип Миколайович Ларін, Роман Юрійович Костюк, Олексій Володимирович Коржик (Автор) https://creativecommons.org/licenses/by-nc/4.0
Features of Analysis of Sound Effects in the Computing Platform iOS
The iOS system is a computing platform and together is a promising modern environment for the development of various multimedia applications. Using the resources of this platform, the user of the mobile gadget appear essentially unlimited opportunities to create different audio signals. In terms of working with sound, Apple is ahead of its competitors, and this is no accident. The company offers good tools for playing, recording and processing tracks. Thanks to this, on the AppStore you can see a huge number of applications that somehow work with audio content. These include players with good sound (Vox), audio editors with tools for editing and applying effects (Sound Editor), voice changing applications (Voicy Helium), and various musical instrument simulators that give a fairly accurate simulation of the corresponding sound (Virtuoso Piano) , and even simulators DJ-installations (X Djing). To work with audio, Apple provides the AVFoundation framework, which combines several tools. If you need to impose any effect, play several tracks at the same time, mix them, do processing or editing audio, or record sound from the output of a certain audio node, AVAudioEngine will help you with this. Most of all this class attracts the possibility of imposing effects on the track. Just on the basis of these effects is built a lot of applications with equalizers and the ability to change the voice. In addition, Apple allows developers to create their own effects, sound generators and instruments. The algorithm for the study of the most common sound effects based on the use of the capabilities of the iOS information platform has been built. The Model-View-Controller Architecture is described in the form of application components, which is the basis for an experiment on analyzing the features of multimedia content based on the use of mobile gadgets and a special programming language. A simple algorithm for using special frames in an XCode environment was constructed, which allowed testing on a selected sample a series of sound effects. It has been found that the built-in algorithm for analysis of samples based on iOS resources can greatly simplify the process of studying sound signals of various nature, because the simulator tools are described through the code of the programming language, and therefore their configuration is a clear approach to the analysis. In addition, the described elements in the article can be used to create their own sound effects, and at various stages of the design of virtual sound generators. Ref. 7, fig. 6, tabl. 1.
Copyright (c) 2019 Гліб Олександрович Борисов (Автор) https://creativecommons.org/licenses/by-nc/4.0
Applying the Concept of a Virtual Competitive Window to Determine the Qualitative Performance of a Wireless Network of the 802.11 Standard
The article presents the results of the application of the concept of a virtual competitive window to determine such qualitative indicators as the bandwidth of the wireless network Wi-Fi, delay transmission of the data packet through the wireless channel, the probability of loss of data packet, jitter. Practical calculations was made for a network operating on the 802.11a specification in RST / CST mode, taking into account the collisions occurring on networks with a large number of active stations. The article considers the ideal network. That is, the one that was neglected by the effects of interference and interference occurring in the real wireless network. The paper examines processes in a wireless network with saturated load as quasi-stationary processes. On the basis of such a concept, the parameter named "Virtual Competitive Window" was introduced. Our research has allowed us to obtain the calculated relations, which establish the unequivocal connection between the system parameters of the network and the stochastic parameters of the network operation process. The results of the research are useful for improving the settlement ratios for determining the parameters of the quality of the 802.11 wireless network in the mode of competitive access. The above calculations do not take into account the effects of interference and interference occurring in the real wireless network. The calculation takes into account the time spent on transmitting the headings and checking blocks provided by the mentioned protocols, as well as the costs associated with the use of the SNAP protocol. The calculation is made for frames with different loads, namely: 64, 128, 256, 512, 1024, 1500 bytes, for networks in which the number of active stations varies from 2 to 14. To calculate the parameters of the network operation, which are provided for signal speed, are used. 24 Mbps (maximum required speed of the 802.11a specification). The calculations are made for cases where the data is transmitted using the protocols TCP and UDP. Chart of network operation in RTS / CTS mode is presented in the article. Thus, the results of the research are graphical dependencies for maximum bandwidth of the 802.11a wireless network in RTS / CTS mode, 802.11a wireless network bandwidth in RTS / CTS mode with allowance for collisions, the dependence of the average latency of data transmission on the 802.11a network in RTS / CTS mode and jitter change curve in a network with a different number of stations in the payload mode of all frames of 64 bytes. Determined that the transmission delay of the data frame depending on the type of multimedia information (small volumes for voice traffic and large for the transmission of digital data) can vary in very wide ranges from 450 to 1300 microseconds, and jitter from 600 to almost 4000 microseconds (for example, files from payload of 64 bytes). The research is relevant because, under ideal transmission conditions, without taking into account signal processing delays by hardware, the maximum bandwidth of the 802.11a network channel in RTS / CTS mode may vary several times compared to the declared 24 Mbps rate. Ref. 4, fig. 5.
Copyright (c) 2019 Ченьлянь Інь, Володимир Семенович Лазебний (Автор) https://creativecommons.org/licenses/by-nc/4.0
Software Tools for Handling Information for the Internet of Things
The analysis of methods of creation of software for information processing for the Internet of things is described. The methods of creating separate stages of the development of applications for reading information and managing Internet speeches are explored. Comparative tables of efficiency of different methods are given, depending on development criteria. A table for analyzing the effectiveness of a combination of different methods for creating front-end and back-end parts of information processing tools for the Internet of Things has also been developed. In this stage of the development of modern technologies, the important place does young, but a very prospective direction is the internet. Specifically, special warnings a technical realization is provided. Differential developments, including the following, before connecting to the network, connect to the user through any wireless network, and enhanced the use of this device. They are constantly improving and appearing new. Urgently important to provide comfort use with a maximum remote control and number of functions, an important role will play the speed and comfort the data management additional. Software internet risk is strongly risks, and that and users 'requirements to contribute and functionality of applications rise the quantity of fast. That the developer appears complex, currently intractable, problem: you need to develop application with a convenient and pleasant user interface designs, maximum performance and response to user actions, and with broad functionality. Theme is actual, that this sphere is very strongly developing, in all your funds investigated in that foreign year. Internet range development is used in different industries, as industry, and sustainable life. Specially in medicine; in the military sphere; in the sales area; in the field of personnel selection, and others. This technology makes life of people and makes it faster. The client, going into the application, sees the display of the front-end parts of web application, that is, the client side of the user interface to the software and hardware part of the service. It contains information about the object, which is taken from the database through the Internet through back-end, that is, software-hardware part of the service. To change certain parameters of the object, the client makes adjustments to the corresponding field of the application, this data fall into the client side of the user interface, from which are redirected to the software and hardware part of the service. After processing – data through the Internet goes to the server. Checking whether the user's requirements for object changes are to display the status of the object in the application. This method is not the only, but the simplest and most visual. In the research component of this article, only the most effective and most common methods of developing the front-end and back-end parts of the application are considered. Ref. 12, fig. 3, tabl. 3.
Copyright (c) 2019 Денис Олександрович Волосян (Автор) https://creativecommons.org/licenses/by-nc/4.0
Visual Programming Tools for Creating Video Effects
Visual programming is a technology that allows you to create program code using graphic elements, not text. Graphic elements are used to describe the logic of the program. Visual programming provides the opportunity to describe processes in an easy to understand representation and sufficient level of abstraction. The paper considers the potential of using visual programming in visual arts. The software / Max / MSP / Jitter was considered. Max, also known as Max / MSP / Jitter, is a visual programming environment for music and multimedia developed and supported by Cycling '74 based in San Francisco. Max is a visual programming environment; MSP is an extension that makes it possible to work with audio, and Jitter is an extension for working with video. Hence the name is Max / MSP / Jitter. Max is a great space for creativity and requires minimal programming experience. It is an environment that contains a set of tools for creating unique sounds, beautiful rendering and exciting interactive media. These tools (called "objects") are small programs that perform specific functions. Some generate noise, others process video, some just perform arithmetic operations. Max, as a rule, is studied by compiling a dictionary of objects and how they function in Patchwork. Most objects are not graphical, consisting only of the object name and several attribute arguments (in essence, class properties), entered in the object field, other objects are graphical, including sliders, numeric fields, dials, table editor, drop-down menus, buttons and other objects for interactive program launch. Max / MSP / Jitter comes with about 600 such objects as a standard package; Extensions can be written by third-party developers like Max patchers (for example, by encapsulating some patcher functions in a sub-program that itself is a Max patch), or as objects written in C, C ++, Java, or JavaScript. Max interacts with OSC, MIDI, and HTTP, among many other protocols, and can handle input from external devices, such as Arduino (Arduino IDE is a development programming environment that is designed to program the same name card. Today, Arduino designs all kinds of interactive , educational, experimental, entertaining models and devices) through the setting of the serial input. It makes Max a great tool for working with visual art, a form that often uses existing video as a source material and offers many applications — interactive installations, light shows, trans-spatial design (visual projection mapping) and concert visual effects. Ref. 10, fig. 4.
Copyright (c) 2019 Марина Миколаївна Волуйко, Юрій Олексійович Оникієнко (Автор) https://creativecommons.org/licenses/by-nc/4.0
Device for Automated Measurement of Volt-Ampere Characteristics
The device, which allows automated measurement of volt-ampere characteristics of semiconductor devices, is developed. The device is implemented using the microcontroller of STM32F4 series, DAC, voltage–current transform circuit, voltage and current sensor and a laptop with LabVIEW programming environment. A wide range of current measurement is possible - from 25 μA to 800 mA with current control up to 0,4 μA. The digital voltage value from the microcontroller is transmitted to the AD5624R DAC via the SPI interface. AD5624R is a 12 bit four channel DAC with built-in voltage reference of 2,5 Volts. Using two DAC channels allowed to increase the resolution of voltage control to up to 12 μV. The voltage-current transform circuit consists of two precision operational amplifiers AD8510 and OP97 with low offset voltage, n-channel and p-channel field-effect transistors with low leakage current and threshold voltage. In the device it is important to control the offset voltage in order to provide a minimum initial current through the sample tested. The schematic is discussed for expanding the measurement range and compensating for the error of the zero code from the DAC. In the circuit, coarse control of the output voltage is implemented with a step of 1,2 mV, and fine control - with a step of 12 uV. Two channels of the DAC channel C and D were used for this purpose. The device circuit also provides compensation for the error of the zero DAC code. Among the resistive current sensors, we chose the INA226 chip, which can be purchased on the so-called "breakout" board. This sensor is one of the most accurate among analogues, containing a 16-bit ADC and providing digitized values of current and voltage at the output. The developed device has a linear dependence of the code to current. The linearity of current control is confirmed to have the correlation coefficient 99,9%. The approach to calibrate the device is described, which will minimize the error and expand the range of measurements. In order to correct the INA226 readings, correction coefficients are used, so that the approximated line equation for the precise voltmeter readings and the INA226 readings match. It is possible to use the approximated values of the current for obtaining the volt-ampere characteristic in the "subthreshold" region when the voltage on the sample is less than the threshold voltage and current values are low (less than 1 mA), and the correted values from INA226 for building the volt-ampere characteristic in the "upper threshold" region, when the voltage on the sample exceeds the threshold and current values are higher. Ref. 12, fig. 8.
Copyright (c) 2019 Дмитро Вікторович Гуменюк (Автор) https://creativecommons.org/licenses/by-nc/4.0
The topic of the article relates to the direction of digital image processing. The main topic of the article is the method between the frame difference. The task is to get acquainted with the basic principles of constructing monitoring systems that are used to detect objects of various kinds by analyzing images. Under the analysis of images in this paper, one should understand the pixel subtraction of two images. In this paper, describe the typical problems that concern a system of this kind. Also, features of the use of other methods that can be used for analysis in such systems are described. The purpose of this method is to analyze the methods of processing images that need to be taken into account in order to implement one of the methods of such a system in practice. To implement it in practice, the method of segmentation is selected, later on. Terms of work with hardware solutions, the data they work with and the data that are used by the user after processing can vary greatly. For example, if you are dealing with a binary black and white image, you need to historically simplify it compared to the random, when the input across all-round raster with paid cross-colors from one to the other. The image can be enlarged with a static camera location, so all the frames will have each other background with possible differences in lighting level. On the other hand, the camera located on the moving object may be different with respect to it. The noise level can vary greatly. Natural phenomena, such as rain, snow, fog, wind, can make a noticeable element in the primary real estate. Please describe what manipulations can be made with one or more frames that should be in this case. Most single-dimensional signal processing methods (for example, a median filter) are applied to two-dimensional signals that are an image. Some of these one-dimensional methods are considerably complicated with the transition to a two-dimensional signal. Signal processing is widely used for Fourier transforms, as well as wavelet transform and Gabor filter. Image processing is divided into processing in the spatial region (brightness transformation, gamma correction, etc.) and frequency (Fourier transform, etc.) This article is an overview on the topic of image processing, which deals with the topic of searching for moving and static objects through image analysis. It mentions typical tasks for image processing, editing and retouching, compensation for loss of sharpness, text recognition, computer vision and methods for processing them: gradation, spatial, arithmetic logic. One of the arithmetic-logical methods, the method of segmentation was described more widely. Those signs that must be taken into account when constructing a processing system based on it: texture, shape, motion, brightness. The next stage in the study of this topic will be the construction of a mathematical model in the high-level MATLAB mathematical calculations system. Ref. 4, fig. 1.
Copyright (c) 2019 Олександр Васильович Дячук (Автор) https://creativecommons.org/licenses/by-nc/4.0
Methodology for Calculating the Parameters of a Reactive Compensator of a Linear Asymmetric Load of a Three-Phase Three-Wire Network
The article describes the method of calculating the parameters of a reactive compensator of a linear asymmetric load of a three-phase three-wire network, which allows to increase the power factor of an asymmetric load to a unit value. It is shown that as a result of the use of a reactive compensator, the power loss in the transmission line can be reduced to two times. In this paper the main equation for the calculation of the parameters of the reactive compensator is derived. The reactive compensator of the circuit with asymmetrical two-arm active load is synthesized. The method is illustrated by an example of a scheme with asymmetric single-cell active load. As known, the unbalanced load of three-phase three-wire power systems leads to a deterioration in the quality of electricity, which manifests itself in the emergence of reciprocal currents and pulsations of instantaneous power, which cause additional losses on the active supports of the transmission line and asymmetry of supply voltages in the nodes of the overall connection of loads. In order to balance the asymmetric stationary linear load, passive filters on reactive elements are effectively used, the calculation of which is based on two approaches: the removal of the pulsating component of instantaneous power and the compensation of the inactive components of the input currents. Among various possible methods, the inductive-capacitive systems are of particular importance. When the limit values of unbalance factor, specified in standards are exceeded, the use of symmetrization systems is required. A symmetrizator should not cause significant active power losses during operation; it implies that the symmetrization process shall be carried out by means of reactive elements (LC) or using active methods (power electronic systems).The purpose of a compensator is to measure adequate electric quantities of the load and generate in the compensator such currents, that the resultant load: compensator-compensated load, as seen from the supply network, was symmetrical, and the fundamental harmonic reactive current drawn from the network did not exceed the value permitted in the supply conditions. In the work vector diagrams of currents and voltages are constructed, power loss is calculated. As a result of the work done, it was established: 1) Increasing the power factor of the three-phase system to the maximum unit value leads to a gain in power loss. 2) Losses in the wires unbalanced system in 2 times more loss symmetric system, and power factor for unbalanced system in square root of two times less than a coefficient symmetrical. Ref. 3, fig. 8.
Copyright (c) 2019 Анна Миколаївна Хвіст (Автор) https://creativecommons.org/licenses/by-nc/4.0
In the article show the basic principles of metal detection, proposed methods for measuring the quantities by which the type of metal can be determined, and methods for improving the accuracy of metal detection and classification. A hardware implementation of a data processing and analysis unit for determining the type of metal has been developed. Digital data processing tools were used for the implementation, which allows to simplify the block design, minimize possible errors and noises during measurement, distorting the final result of the detection and classification of metals. In the modern world people has to deal with a large number of different metals. There is a problem of distinguishing one type of metal from all others. Such a function of metal detectors is called discrimination. Metal Detector Discrimination is a function that allows you to recognize marked objects by metal type and classify them. Modern high-precision metal detectors contain a large number of functional blocks, complex in setting up and use, sensitive to noise and errors during measurement and detecting metal. The task is to design a unit for discrimination of metals that would consist of a minimum number of functional units, required minimum number of settings and could give correct information about the presence of metal and type of metal and will be insensitive to disturbances caused by the noise and errors during measurement. Metal detectors operate on the principle of magnetic field generation and analysis of the feedback signal from a metal object and the environment. The transmitted magnetic field varies in time. The transmitter is made as coil with an electric current of a certain shape, passing through it and obtained from the generator block. The receiver is made as receiving coil connected to the amplification, filtering and processing unit of the received signal. Any metal has the properties of the resistivity and the properties of the inductance. Using information about the phase difference and amplitude between transmitted and received signals, we can determine type of the metal. To find the phase and amplitude of the received signal, the signal from the metal can be divided into two components: quadrature component has the same form of signal as the transmission signal, but is shifted in time relative to the transmitted signal (phase difference); in-phase component has the same form of signal as the signal transmitted, but, the amplitude of the received signal changes. Then using this two components find the phase and amplitude of the signal. To increase accuracy of the measurement using “ground balancing” principals, and ferrite calibration. As a result get the block for metal discrimination with simple design, minimum number of setting and good capabilities to minimize noise and errors during measurement. Ref. 12, fig. 8.
Copyright (c) 2019 Олександр Володимирович Цимбал (Автор) https://creativecommons.org/licenses/by-nc/4.0
Application of a Neural Network for Stylized Image Processing
Manually redrawing an image in a certain artistic style takes a professional artist a long time. Here you can use image representations derived from the Neural Networks. It is considered the problem of image processing using convolutional neural network. The article deals with the typical architecture of the convolutional neural network, the advantages of their use in problems associated with pattern recognition are presented. The problem of artist style transfer where the painting style of a given artist is applied on a real world photograph is addressed. approach uses the statistics of high-level feature representations of the images from the hidden layers of an image classification network to separate and reassemble content and style. To automatically transfer an artistic style, the first and most important issue is how to model and extract style from an image. Transferring the style from one image onto another can be considered a problem of texture transfer. In texture transfer the goal is to synthesise a texture from a source image while constraining the texture synthesis in order to preserve the semantic content of a target image. Since style is very related to texture, a straightforward way is to relate Visual Style Modelling back to previously well-studied. After obtaining the style representation, the next issue is how to reconstruct an image with desired style information while preserving its content, which is addressed by the image reconstruction technique.This is done by formulating an optimization problem that, starting with white noise, searches for a new image showing similar neural activations as the content image and similar feature correlations as the style image. A Neural Algorithm of Artistic Style is a pattern that can be separate and recombine the images is introduced. The algorithm allows us to produce new images of High quality perceptual artworks. The result provides new insights into the for high level representations image synthesis and manipulation. The result was generated on the basis of the VGG network , which was trained to perform object recognition and localisation The usage of convolutional neural network is analyzed. Representations that factorise the variation in the content of an image and the variation in its appearance would be extremely practical for this task. In light of the striking similarities between performance optimised artificial neural networks and biological vision, the human ability to abstract content from style – and therefore our ability to create and enjoy art – might also be primarily a preeminent signature of the powerful inference capabilities of our visual system. Ref. 10, fig. 6.
Copyright (c) 2019 Олександра Юріївна Колесник (Автор) https://creativecommons.org/licenses/by-nc/4.0
Reserve Power of the Household Gas Boiler Control Module
The paper deals with problems caused by interruptions in the power supply of a gas boiler. It is proposed to use the Stirling engine to ensure uninterrupted power supply of electronic automation devices. The work also describes the principle of operation of the engine in question and calculates the evaluation of its efficiency when using the backup power supply as a source. The Stirling engine operates behind the closed Stirling cycle. The unchanging amount of the working substance circulates between two chambers with different temperatures, which alternately heats and cools. Due to this, the pressure of the working substance, which moves the working pistons, changes. The work of a modern gas boiler is impossible without an electronic control module. But when the network voltage disappears, the heating also disappears. Therefore, it is necessary to ensure uninterrupted supply of electric current to the control module. Today, the market is full of gas air heaters or gas heat guns of various manufacturers, and there are already attempts to use them to generate electricity. To generate mechanical energy, which in the future turns into electric and thermal energy, allow thermal motors. Modern directions of transformation of thermal energy into mechanical and electric are: Stirling's engines; cars working on the Renkin cycle; thermoelectric generators on the effects of Seebeck, Thomson and Peltier. A review of the advantages and disadvantages of individual components of the Stirling enginewas made. Compared to internal combustion engines, the Stirling engine has a number of advantages. It does not have complex fuel systems, it is practically silent, can operate on any type of fuel or thermal energy, has high adaptability, and also high theoretical efficiency of 50%. The disadvantages of Peltier elements include very low efficiency and high element cost. However, in spite of this, Peltier elements are used to cool various devices and as generators for power generation for the on-board networks. It is proposed to use the Stirling's engine to ensure uninterrupted power supply of electronic automation devices. On the basis of the performed calculations of the efficiency, a conclusion was drawn on the potential for further development of the proposed solution. These calculations show that, given the device's power is 525 Watts and considering that the boiler electrical equipment consumes 250-400 W, the proposed idea has the potential for further development. Ref. 10, fig. 3.
Copyright (c) 2019 Михайло Д. Татарников, Поліна І. Трояновська, Сергій Б. Могильний (Автор) https://creativecommons.org/licenses/by-nc/4.0
Comparison of Inverter Topologies by Total Har-Monic Distortion of Output Voltage
This paper is devoted to comparison analysis of different topologies of the inverters that are used in the systems with alternative energy sources. A brief theoretical review of the most commonly used topologies for the power systems with alternative energy sources are given, their main advantages and disadvantages are determined. In close details were considered principles of construction and operation of the topology with impedance input circuit (z-inverter), and topology with quasi-impedance input circuit (quasi-z-inverter). A special feature of these topologies is ability to operate in special mode which is called “shoot-trough state”. It means that one of the inverter’s arms is short-circuited for a small period of time which substitutes a part of the zero state. Possibility to operate in such state allows to increase the input voltage of the inverter that can be very suitable in inverters that are included in photovoltaic power systems. Implementation of shoot-trough state allows tracking maximum power point of the photovoltaic array without implementation of additional converters for this. Implementation of quasi-z-topology allows to reduce the load on the passive components of the impedance circuit and to ensure continuous power take-off from the solar batteries array, which makes it easier to track the maximum power point. As an evolution of the cascade multilevel and z- / quasi-z-inverter topologies multilevel cascaded topologies with z- and quasi-z-inverters in separate blocks were considered. The main principles of this structure allows to unite all advantages of cascaded multilevel and z-/quasi-z topologies in one device but also bring few drawbacks such as complexity of the implementation and higher cost of the resulting device. These topologies were simulated in Matlab Simulink, output voltage spectra and total harmonic distortion was obtained and analyzed. According to the obtained results of the simulation and review recommendations for proper selection of the topology of inverter depending on the type and sensitivity to the quality of the input voltage of the load and type of chosen alternative energy source are given. According to this results convenient cascaded multilevel topology could be recommended for the loads that are especially vulnerable to low quality of input supply voltage such as analog amplifiers and radio receivers as topology that have lowest THD (Total harmonic distortion) ratio. Z-/quasi-z-topologies are appropriate to consider as a converter of photovoltaic power system that will work on loads that are not demanding to the quality of supply voltage as topologies with highest level of THD of the output voltage. Cascaded topologies with z- and quasi-z-inverters in separate blocks could be considered as a compromise that could be used in photovoltaic power systems that works on vulnerable loads but such solution increases the cost of a whole power system and complication of the control system.
Copyright (c) 2019 Ігор Сергійович Федин (Автор) https://creativecommons.org/licenses/by-nc/4.0
Struggle with noise pollution on the railway
Living in cities, people are faced with various problems that arise in everyday life. One of the most harmful problems that causes diseases in humans is noise pollution. The growing noise pollution of the big city also causes a lot of troubles to the citizens, negatively affects their health and mental condition. With the development of all types of transport, intensive construction, noise loads per person increase, causing its annoyance, mental imbalance, insomnia and, as a consequence, cardiovascular and mental illness. Now, in the streets of Kyiv in many regions, noise sometimes reaches 80-90 in the daytime, and 50-60 decibels at night, which is not a normal phenomenon. So, it was decided to find a site where noise would exceed the norm, and the main source of its nature would be the railroad. Having conducted experimental research on this section of the railway, noise levels were determined. Consequently, the equivalent noise level is 61 dBA, equivalent to the noise level of the flow of trains was 64 dBa, the maximum noise figure recorded in this section was 85 dBA. This experiment was conducted at night with the greatest intensity of trains. So, as the standard (DBN 360-92), the equivalent noise level in the period from 23 h - 7 h should not exceed 45 dBA, and the maximum noise level should not exceed 60 dBA. So we see a significant deviation from the norms, so you need to develop methods to combat noise. Since the selected site was densely built up, which made it impossible to combat noise by the method of forest plantations, so this issue was solved by establishing appropriate noise protection structures that would operate on different sources. Knowing that the noise arises not only from the rumble of the tractor of our tractor train, but also the rattle of the wheels on the track and the flow of air of the train body. So, to reduce noise, you need to consider all these sources. Consequently, in order to reduce the noise caused by rolling the wheel along the track, it was proposed to install road dampers and liners that reduce noise to 10 dB. And to reduce the noise already in the air, it is proposed to install noise protection screens of a height of at least 2m, which allows to reduce the noise level by another 15 dBA. Execution of these conditions will allow us to reduce the noise level in this area by 16 - 20 dBA. (the equivalent noise level should be reduced to 41-45 dBA). Consequently, this experimental study carried out showed us the need to carry out such experiments not only along the whole railway connection of the city of Kyiv or other cities of Ukraine, but also measurements on automobile or ship solutions or construction sites. This will detect problem areas, and depending on the source of noise, fight with them to improve the noise background. And this, in turn, will have a positive effect on the psychological state of man. So let's make a world in which we live better!
Copyright (c) 2019 Владислав Ярославович Рижко (Автор); Олексій Вікторович Богданов (Перекладач) https://creativecommons.org/licenses/by-nc/4.0
The analysis of the single-crystal transceivers work in the range of ISM for IoT systems
The article discusses the features of transceivers for IoT systems. IoT systems are used in areas such as medicine, security, industrial automation, intelligent networks, remote control facilities, engineering and security systems of buildings. These applications require highly integrated transmission and reception components that can provide low power consumption for longer life, high probability data transfer, ability to operate in the unlicensed frequency range, simplicity and reliability of operation, scalability without significant additional costs and compliance with international standards. Analog Devices ADIsimSRD Design Studio is a very powerful tool allowing real-time simulation and optimization of many of the parameters in a typical wireless system using the ADF7xxx family of transceivers and transmitters. By modeling in the ADIsimSRD Design Studio software, the operation of the single-chip transceiver ADF7023 was analyzed. The ADF7023 is a very low power, high performance, highly integrated transceiver designed for operation in the 862 MHz to 928 MHz and 431 MHz to 464 MHz frequency bands, which cover the worldwide license-free ISM bands at 433 MHz, 868 MHz, and 915 MHz. It is suitable for circuit applications that operate under the European ETSI EN300-220, the North American FCC, the Chinese short-range wireless regulatory standards, or other similar regional standards. Data rates from 1 kbps to 300 kbps are supported. The range of subsystems to be considered in the development process include RF filtering/matching, modulation type and demodulation process, packet data formatting, and average power consumption. Until now, system designers relied on a combination of spreadsheet-based tools and iterative lab work to help with the optimization of these parameters. Based on the analysis, recommendations were made on the choice of transmitter parameters for the implementation of IoT systems using Analog Devices chips. Due to low energy consumption, high integration, ability to operate in the unlicensed ISM frequency range, high probability and speed data transfer capabilities, module programming capabilities, compliance with international standards, Analog Devices transceivers can be used in wireless IoT communications systems. To ensure a good communication range and a high probability of information transfer, it is advisable to use the most noise-resistant GFSK modulation method, which provides the most energy-efficient narrow signal spectrum.
Copyright (c) 2019 Ольга О. Титаренко, Володимир Васильович Макаренко (Автор) https://creativecommons.org/licenses/by-nc/4.0
Subjective Assessment of the Intelligibility of Noised Speech in Lecture Room
Subjective assessment of the speech intelligibility is of great practical interest, since this parameter can be used in many engineering and natural-mathematical fields, such as bioengineering, design of lecture rooms and concert halls, mathematical modeling and medicine. By this time, several attempts were made to assess the intelligibility of the room. The results of such experiments became conclusions: 1) early reflections improve the intelligibility of distorted noise and reverb speech; 2) using binaural type of listening we will have better intelligibility than with monoural. But to re-implement such experiments, it is necessary to use a lot of expensive equipment, which is not always possible. Therefore, the purpose of this work is to study the influence of the characteristics of the room on the speech intelligibility without the use of a large number of equipment. The idea of the experiment is as follows: distorted by noise and reverb signals must be listened to by the participants in the experiment, the perceived sound is fixed and compared with the undistorted signal. The clear signal was recorded using a microphone, sound card and audio file software. Synthesis of distorted signals took place in two stages: 1) adding white noise; 2) filtering the resulting mix through a non-recursive digital filter using the impulse characteristics of the room for six distances to the source of sound. The mathematical model of the distorted (output) signal was the convolution of an additive mix of clear signal and white noise with a pulse characteristic. To ensure the necessary signal-to-noise ratio, the noise was weighed by the corresponding coefficients at the stage of adding it to the clear signal. Testing was carried out in five stages: 1) simulating of distorted signals; 2) voicing signal to participant; 3) signal listening; 4) fixation of the perceived sound; 5) intelligibility calculating. For testing, six binaural impulse characteristics of the room with known parameters from the Aachen database of impulse characteristics were used. Each of the impulse characteristics corresponds to a certain value of the distance from the sound source to the microphone. After the completion of the experiment, the overall result was obtained by averaging by the number of participants. The overall result has shown that for small values of the signal-to-noise ratio over long distances, the intelligibility is greater than for small distances. For high values, the signal-to-noise ratio is better for small distances. Such results may be explained by the fact that, at long distances, the combination of the effects of early reflections and binaural listening positively affects the intelligibility. The main reason for the low intelligibility of the distorted by noise speech in the room is a late reverberation. As a conclusion we can say that the computer modeling method makes it easy to create a distorted by the noise and influence of the room signal; It is shown that, for small values, the signal-to-noise ratio is more readable than for small distances.
Copyright (c) 2019 Олексій Олегович Андрійченко, Олександр Ігорович Денисенко (Автор) https://creativecommons.org/licenses/by-nc/4.0
The choice of guitar interactive learning system hardware
The principles of pickup and signal processing of individual strings of the guitar are described. The existing sound pickup and processing systems, as well as their signal visualization and interactivity capabilities, are investigated. The possibilities of using these systems for learning to play the guitar are considered. A practical implementation of the hardware of an interactive system that can be used to learn to play the guitar is given. The existing and proposed systems are compared, the pros and cons of each system are highlighted. One of the most popular musical instruments is a guitar. You can study guitar playing at a music school or yourself, using books or educational videos. But they do not provide corrections for students' mistakes. Therefore, the development of an interactive learning system is relevant. Elements of the interactive system are all elements that are involved in the process of data exchange with another system or with a person. It needs a pickup for each string. Such information can only be obtained by special sound pickup and sound processing devices. There are systems that use the pickup for individual strings, but they are not interactive, and therefore cannot be used as teaching. Also, these systems are expensive and require additional equipment. As a rule, the sound from pickups for each string is used to form a digital signal in the MIDI format and further create different musical effects. The MIDI abbreviation stands for Musical Instrument Digital Interface, which refers to a complex of industrial specifications for various sound sources that allow the generation of such musical information, regardless of the device (or model) of that or another manufacturer. Wherever the MIDI command arrives, it will immediately generate the sound corresponding to it. Thus, through this interface you can control an entire electronic orchestra from one remote control. Very often such devices in appearance look like a piano keyboard and are accordingly called MIDI-keyboards. But on a computer the control panel is often implemented software in the form of a special application - a sequencer. Not always used to create music MIDI keyboard. Sometimes a MIDI signal is used to transfer guitar information. The purpose of the work is to analyze the possibility of using the existing MIDI guitar sound processing units for use in the interactive system. The hardware of the developed interactive system for learning to play the guitar is considered, and also compared with existing systems.
Copyright (c) 2019 Інна Андріївна Шевченко (Автор) https://creativecommons.org/licenses/by-nc/4.0
Research of technical features of the Arduino based RFID system
In the article the features of creation of the system of radio frequency identification on the basis of Arduino interface software are considered. This model of the system has its own technical features of the configuration, characterized by the implementation of the algorithm of programming the components of the system, initialization and authentication of the object on the basis of special access tags - a card and a key. The constructed access model can be used to identify objects in special security systems. It is determined that the created module in various operating modes has its technical limitations, which are determined by the limited radius of action, the form of the reader and the design of the radio frequency tag. Most transponders consist of two parts. The first is an integrated circuit (IC) for storing and processing information, modulating and demodulating a radio frequency (RF) signal and some other functions. The second is an antenna for receiving and transmitting a signal. The reader has a transmitting device-it sends a signal to the label and receives the corresponding signal from the label. The microprocessor (passive label) that sends the signal is powered by the induction current from the coil or an antenna in which the current is produced when the label passes through the electromagnetic field. Labels may have a more complicated implementation with a microprocessor that checks and decodes the data, and not simply matches the identifier, as well as the memory that stores the data for the next transmission, if necessary. The reader is engaged in the generation and propagation of electromagnetic waves into the surrounding space. This signal is received by an RFID tag, which creates a feedback signal picked up by the reader’s antenna, then the received information is decoded and processed by the electronic unit. An object equipped with an RFID tag is identified using a unique digital code that is stored in the memory of the electronic tag. For example, you can get individual user data or the identification number of a product in a matter of seconds. It was found that the condition of functioning of the developed system of radio frequency identification is the absence at the given operating frequency and near the scanner of electromagnetic interference of different nature of origin.
Copyright (c) 2019 Максим Сергійович Шапарець (Автор) https://creativecommons.org/licenses/by-nc/4.0
Independent systems for collecting and transmitting data with a wireless communication channel
The need for the protection of material property appeared together with the notion of "private property", that is, immediately after the collapse of the communal system. The desire to hide, to find a cozy place to store such property is at the level of instincts, in this person does not differ from the animal. Therefore, the first stage in the development of a conscious action to prevent the location of the place of storage of property was the commission of special protective and preventive measures. From all sorts of ditches and stones, which laid holes for access to places of storage, humanity in the process of evolution gradually switched to the use of auxiliary devices. The main purpose of the security system (burglar alarm) consists in operative and guaranteed notification of the hosts or law enforcement agencies about unauthorized entry into the premises that are guarded. The decision of this task is possible only with the competent equipping of the object of protection with modern high-reliability technical means of the security alarm system. The security alarm system can be autonomous - the purpose of such an alarm is to scare off the attackers and announce neighbors with the use of powerful sirens. But the greatest effect of the burglar alarm is achieved by connecting it to the remote control unit or on the central monitoring panel of the private security company. Systems of any complexity are built on the basis of the same technical devices. When solving technical tasks of security, it is first necessary to choose the basic parameters of devices that will provide sufficient reliability of the functions assigned to them. The system of the security alarm fixes the fact of unauthorized access to the protected area, transmit an alarm, for example, to the remote control and include executing devices. The system of the security alarm system includes: sensors, remote-concentrator, actuating devices. Independent systems that read and transmit information are up to date, thanks to individual sources that allow the device to function independently, without communication with power systems. They use them where the objects are impossible or problematic to connect to the main line of power supply. The main advantage of this system is that the device can function continuously, regardless of the stationary power supply. This is important when using appliances that require constant power, such as signaling or autonomous heating. Therefore, these systems have become widely used, they operate in stand-by mode and are characterized by low energy consumption, but energy is not endless., considered various options for recharging and options for the implementation of data transmission. In order to restore energy resources, various options for recharging have been considered and proposed. Also, to save energy, various ways of data transmission, their advantages and disadvantages in the energy plan, dependence on external factors, range of action and method of information transmission were considered. On the basis of this, the conclusions drawn were drawn on the most suitable for the use of the transmission system in stand-alone systems, which in turn have less power consumption and the most optimal for data transmission, and also considered the expediency of using certain charging methods depending on their advantages.
Copyright (c) 2019 Олексій Переверзєв (Автор) https://creativecommons.org/licenses/by-nc/4.0
Prospects and development of mixed reality technologies
In this article, discusses the gadgets of companies that are the main representatives of the technology of mixed reality. Comparison of technologies was carried out and their differences were determined both in technical design and in the field of application. Comparison of technical specifications and the scope of application for each of the representatives, taking into account the capabilities and support of the software. Microsoft HoloLens was the first working representative of mixed reality. Due to the fact that he worked on the operating system of Windows Holographic, he received the widest application, as far as this personal computer is attached to your head. You can identify the scope of application for each of the devices. The most widely used at the moment is HoloLens, because it works on one variation of the Windows operating system, which allows you to use all commonly used programs in mixed reality mode. Use is available in all areas where necessary from the use of doctors during or during the preparation of the operation, and for the developers of any graphic elements, designers and architects. It supports a full set of programs running on this platform. Meta 2 is a device, to work with which it is necessary to have a sufficiently powerful personal computer, as far as the device itself is used as a monitor, only in mixed reality. Meta 2 for the moment, can be used in conjunction with Microsoft Office, Adobe Creative Suite, and Spotify. Although the list of applications is currently limited, it can now be used to create layouts and designs. And Adobe Creative Suite support allows you to use them to create media content and instantly mix it with the real world. Magic Leap One is very similar to Microsoft HoloLens, also an independent device that does not require additional connection to a PC. Magic Leap One - At the moment, with the support of a small amount of software, this device allows you to arrange online conferences between the users of Magic Leap One anywhere in the world. Allows you to design your own world through Project Create, manage the created elements, and organize the interaction between them. At the moment, it has limited scope due to small software, due to the use of its own operating system. It is noted that compared to the technology of virtual reality, mixed reality allows you to complement the real world with digital content, without loss of visual contact with others.
Copyright (c) 2019 Ростислав Віталійович Денисов, Ю. О. Оникієнко (Автор) https://creativecommons.org/licenses/by-nc/4.0
Action and movements recognition methods
The article describes the formulation of the problem of recognition of the movements of objects in a video sequence, the stages of its solution, the analysis of the basic methods of each of the stages. A wide range of applications and growing requirements on the quality of recognition determines the relevance of the study. The process of action recognition and detection begins with extracting useful features, from the input video sequence. Features are then processed through a classier to identify the action class (for example, running, walking, jumping, various gestures). The article describes the main feature descriptors, in the filter-based category: histogram of oriented gradients, cuboid descriptor, scale-invariant feature transform, gradient location-orientation histogram, local trinary patterns, and spatiotemporal patches, optical flow-based descriptors: histograms of optical flow, the motion boundary histogram, dense trajectory, convolutional neural network-based descriptors. Some algorithms require the extraction of primitive features and further refinement of the auxiliary features before they can be passed to the classifier. Examples of the use of specialized primitive features are methods based on silhouettes / contours and methods based on object tracking. There are methods for classifying extracted features, including the following: support vector machines, adaptive boost, artificial neural networks, convolutional neural networks. The key difficulties arising in solving the problem are considered. There are ways to compare various methods. One of the ways to draw comparisons is to quantitatively evaluate each approach on the same database with the same protocol. From simple KTH datasets and Weizmannnd to Carnegie Mellon University Crowded Videos dataset and Microsoft Research Action Group dataset to more complex video conditions and large-scale UCF101 and ActivityNet datasets. Existing approaches to recognition of motion in video sequences are analyzed. The article reveals characteristics, strengths and weaknesses of the various methods of detecting features and their classification. Leading methods that show the best results widely use convolutional neural networks. One of such methods is a spatio-temporal graph convolutional neural network for action recognition based on the object's skeleton. A method for further research and improvement was chosen.
Copyright (c) 2019 Денис Солдатов (Автор) https://creativecommons.org/licenses/by-nc/4.0
Automated system for determining parameters of a solar cell model
An automated system is developed, which allows measuring the light and dark current-voltage characteristics (CVC) of a solar cell (SC). It consists of a STM32 based control unit, a digital-to-analog converter, a voltage-current transformation circuit, a current and voltage sensor and a laptop with a LabVIEW graphical programming environment. The digital voltage value from STM32 is transmitted to the AD5624R DAC via the SPI interface. AD5624R is a 12 bit DAC with built-in reference voltage 2,5 V. In this configuration, the accuracy of the voltage control is 1,2 mV and the accuracy of the current setting is 40 μA. INA226 sensor was used to measure the voltage on the sample and the current flowing through it. The current is measured as the voltage drop across the shunt resistor, which is connected to the corresponding sensor inputs, using the built-in 16-bit ADC. A shunt resistor with a resistance of 0.1 Ohm is used, which allows measuring the current up to 800 mA with a resolution of 25 μA. The readings of the sensor were calibrated using the precision voltmeter B7-46. Measurement and data processing is carried out with a virtual device created in the LabVIEW environment. As a microcontroller, the SM32F401RE Nucleo development board was used. This unit provides control of the DAC, the current sensor INA226, connection of the circuit for measuring light or dark CVC, as well as recording and storing the data received from sensors in the computer. By measuring the light and dark current-voltage characteristics it is possible to obtain an approximate solar cell model, the parameters of which depend on the illumination and temperature. Solar cell light CVC is used to determine the photocurrent. By its value at a certain temperature and luminosity, it’s possible to define the photocurrent at different temperatures and luminosity levels. The saturation current and the parameter α of the solar cell are calculated using the dark CVC. With the obtained data, a model of a solar cell is defined, which can be further used to determine the maximum power point at different levels of illumination and temperature. With information about the maximum power point, it is possible to calculate the optimal resistance value for the solar cell and to provide the corresponding control signal to the voltage converter. An approach for calculating the parameters of the SC model from its CVC is described and used to determine the MPP (maximum power point) of the solar cell module. The difference with the experimental data was 6.6%. In further research, the study of methods for calculating the parameters of the SC, which could provide a more accurate model, will be continued.
Microprocessor system for determining the intensity of transport motion
The article discusses the basic principles of monitoring traffic and proposed a system architecture using Hall sensors to collect primary information about the movement of vehicles. The basis of the information system of traffic monitoring are visual observers and sensors of road transport parameters. The functionality of the entire information system depends to a large extent on their functionality and data reliability. Modern traffic control systems are based on zonal controllers (LCs), which consist of a sensor for obtaining primary traffic information and microprocessor pre-processing units [1]. Most often use optical and ultrasound sensors, magnetic gates, video surveillance systems [2]. Existing traffic-sensors of foreign production show unsatisfactory results in conditions of intensive traffic of vehicles (TK), parking TK in the traffic lane, visual overlap of TK traffic sensor and moving TZ between bands. This leads to a premature transition of the KK to the functional state of "jamming", and a significant reduction in the informativity of the system. The purpose of the work is to develop a MK that could offset all the above-mentioned shortcomings. Each vehicle has metal elements in its body and, in its movement, it will in one way or another affect the magnetic field of the Earth. Analyzing the perturbation of the magnetic field caused by the movement of the object with ferromagnetic elements (vehicle with steel and iron parts) over magnetic field sensors and measuring the delay between the moments of operation of two sensors can determine the average speed of the object. An experimental sample was developed for experimental verification of the above-described method for collecting primary information. To fix the magnetic field changes associated with the transport of a vehicle, a pair of digital magnetic three-coordinate HMC5883L compasses operating on the Hall effect were selected and have the ability to auto-calibrate to account for the magnetic deviation. Magnetic meter HMC5883L has 3 magnetoresistance sensors, located on three perpendicular axes (Cartesian axes X, Y and Z), which allows to realize the ability to determine the parameters of motion of vehicles that change the lane. To implement the data processing unit, the Arduino PRO Mini board with the ATmega328 processor, which is a low-power 8-bit CMOS microcontroller and a built-in analog-to-digital converter, is used. In the work the method of determination of traffic parameters based on the Hall effect is proposed. The use of sensitive magnetic field sensors - digital compasses is grounded. The block diagram of the traffic monitoring system is proposed and implementation of the area controller using the digital compasses HMC5883L based on Arduino PRO Mini. Using a developed experimental stand, a series of field experiments was carried out that confirmed the possibility of using the proposed method for determining the speed and direction of transport of vehicles.
Copyright (c) 2019 Єгор Максимович Мирошниченко (Автор) https://creativecommons.org/licenses/by-nc/4.0
Thermal fatigue prediction of viscoplastic solder for microelectronic components and systems
An analysis of Micro Grid system performance requires both meteorological and electrical data for the assessment period. However, actual in-field data acquisition is rarely 100%, often resulting in a significant amount of incomplete datasets for performance assessment. These gaps, if not taken into account, may add noticeable bias in yield assessment and thus estimations of the lacking data need to be made. Approaches of back-filling the required data is given and validated here. This paper presents a strategy to back-fill data with good accuracy for both short and long term periods, while taking into account weather as well as system performance variations. Cases of data loss are identified. The first case is that of missing meteorological datasets, while electrical readings are available. This case is met in most small systems, either domestic or commercial, where installers reduce the cost by omitting the meteorological sensors. The second case is that of the electrical monitoring system being interrupted. The third case is a failure of both monitoring sub-systems, which could be due to communication or hardware failures. The last two cases are often met in the majority of solar farms. Two methods, by means of which it is possible to restore the missing data about the status or output current panel, are considered. The method of synthesis of meteorological data and also the method of restoration based on empirical orthogonal functions (EOFs), are considered. Method based on EOFs reconstructs missing data using empirical orthogonal functions, derived from the original data. While EOFs in a complete dataset would typically be calculated using singular value decomposition, the presence of missing data requires an iterative approach. The method allows for the estimation of missing values and full EOFs by first inserting mean values into the missing portions of the dataset and then calculating the EOFs. Because the resulting spatial EOFs and the time series of their magnitudes reconstruct the original data, a truncated version of the original dataset can be generated, using only as many EOFs as are deemed significant through validation. This provides an improved estimate of the missing information over simply inserting mean values, because the small-variance (i.e., noise) EOFs have been removed. Method of synthesis of meteorological data uses data collected from meteorological stations to estimate irradiance. Then module temperature is calculated from in-plane irradiance and ambient temperature using a simple linear thermal model. Using this information electrical performance is estimated. Two methods differ from each other, so detailed analysis and comparison of these methods are performed. The possibilities and requirements for their using are determined depending on the reasons of the loss of information in Micro Grid. The specific systems, that involve Micro Grid, in which methods can be used for providing maximum energy extraction are suggested. These two methods will be used in future research work based on applying the theory of fractals to the analysis of distributed generation systems of solar panels for maximum energy extraction.
Copyright (c) 2019 Миколи Олександровича Корчака, Катерина Сергіївна Клен (Автор) https://creativecommons.org/licenses/by-nc/4.0
Development of the optimal gamma-ray imaging system design
This article covers solutions in the field of the gamma-ray imaging systems, as well as proposes an optimal solution for design of such system. Gamma-ray imaging systems are proving their utility as a useful tool for radio-ecological research, investigation of isotope mishandling, nuclear incidents liquidation and so on. They allow viewing gamma-ray fields as if they were visible. For example, this kind of system is capable of pointing to radiation sources on top of video stream, which allows localization of radiation sources without the need of getting close to them with a dosimeter. Overview of the existing solutions covers directional imagers, collimator-based imagers, coded aperture imagers and rotation modulation systems. Each section of this paragraph outlines main advantages and disadvantages of the given solution. Based on a solution overview, a proposition of an optimal solution for this kind of system is made. Proposition covers a creation of the one-dimensional coded aperture system with modified uniformly-redundant array mask, scintillation detectors and FPGA-based data acquisition system. This kind of system uses a thick screen, also called mask, with holes. This screen casts a gamma-ray shadow onto an array of detectors. Then a data acquisition system is used to run a correlation algorithm, which finds a shadow pattern in detector’s readouts. This allows determining from what angle this shadow has been cast. The mask is formed by a modified uniformly-redundant array pattern to minimize the chance of incorrect correlation algorithm result and to use it’s ability to turn coded aperture into an inverse one. Performing measurements with and inverse mask allows compensation for irregular background radiation and irregularity between detector sensitivity in the array of sensors. It should also be noted, that using of such ability requires to physically turn the mask around it’s vertical axis. This paragraph outlines a number of design principles and requirements, such as avoidance of irregularities in radiation transparency of the mechanical construction, benefits of making the whole system remotely operated, overall requirements for supply and readout electronics and a proposal to use programmable logic integrated circuits as a data acquisition measure. This section also covers possible steps to improve system performance, via turning it around vertical axle, rotation of the viewing frame to create 2-dimensional images and performing correlation algorithm on the spectral data to distinguish different nuclides amongst gamma-ray sources. Overall conclusions of this article suggests an implementation of the test device to verify and field-test proposed technical solutions and to promote further research and development in this field.
Copyright (c) 2019 Олександр Ігорович Магньов (Автор) https://creativecommons.org/licenses/by-nc/4.0