The work is devoted to the problem of providing electrical energy to remote production enterprises in the absence of a centralized power supply. The purpose of the work is to develop decision support tools for choosing autonomous power generation projects from a large number of possible alternatives. To achieve this purpose, a hierarchy of criteria was constructed and a comparative analysis of existing technical and economic solutions in the field of small-scale autonomous energy was carried out. It is shown that when choosing a power generation project for a particular enterprise, there is a fairly large number of alternatives, which makes the use of commonly used decision support procedures based on the hierarchy analysis method/analytical network method (in the classical version) ineffective. An iterative procedure with dynamic changes in feedback between criteria and alternatives is proposed, which makes it possible to reduce the dimension of the supermatrix during the calculation process and, thereby, reduce the time complexity of the algorithms. The effectiveness of the proposed modification of the analytical network method is confirmed by calculations. The constructed procedure for selecting an autonomous power generation project makes it possible to increase the level of scientific validity of technical and economic decisions when expanding the production activities of small enterprises in remote and sparsely populated areas.
Keywords: autonomous power system, decision support, analytical network method
The article discusses the use of a recurrent neural network in the problem of forecasting pollutants in the air based on actual data in the form of a time series. A description of the network architecture, the training method used, and the method for generating training and testing data is provided. During training, a data set consisting of 126 measurements of various components was used. As a result, the quality of the conclusions of the resulting model was assessed and the averaged coefficients of the MSE metric were calculated.
Keywords: air pollution, forecasting, neural networks, machine learning, recurrent network, time series analysis
The paper analyzes various approaches to identifying and recognizing license plates in intelligent transport networks. A deep learning model has been proposed for localizing and recognizing license plates in natural images, which can achieve satisfactory results in terms of recognition accuracy and speed compared to traditional ones. Evaluations of the effectiveness of the deep learning model are provided.
Keywords: VANET, intelligent transport networks, YOLO, city traffic management system, steganography, deep learning, deep learning, information security, convolutional neural network, CNN
The article presents aspects of the development of a device for wirelessly picking up a vibration acceleration signal from the surface of a ball mill drum. The results of measuring vibration acceleration for a ball mill model for various levels of loading with crushed material are presented. According to these results, with an increase in the load of crushed materials relative to the ball, the level of vibration decreases. The work also presents the obtained pie diagrams of the distribution of vibration load across the mill drum, from which one can judge its current operating mode.
Keywords: ball mill, wireless signal, vibration acceleration, mill loading control
Using numerical modeling, a study of heat transfer and hydrodynamics in plate heat exchangers with corrugated fins was carried out, while the height of the corrugation profile varied from 2 to 4 mm. The influence of profile height on heat flow and pressure drop was studied. It was revealed that an increase in the profile height leads to an increase in heat flow up to 34.05% and pressure drop up to 54.54%.
Keywords: corrugated heat exchanger, cooling system, microelectronics, profile height, heat flow, pressure drop, heat transfer, hydrodynamics, calculation, numerical modeling
Asphalt concrete mixes are the primary construction material for road surfaces, and precise design of their composition plays a key role in the quality and durability of road pavements. This article discusses the challenges associated with designing asphalt concrete mix compositions and presents a developed system for automatic mix selection. The automatic asphalt concrete mix composition selection system is a powerful tool for optimizing the material selection process used in road construction. This system can calculate the optimal mix composition, taking into account technical and economic constraints, leading to increased accuracy and reliability in mix selection. The advantages of this system include reducing the time and cost of the selection process, enabling testing and analysis of various mix options, ultimately improving the quality and durability of road pavements.
Keywords: asphalt concrete, asphalt concrete mix, composition selection, least squares method, linear programming method, software, automation, Python, Microsoft Access
In this paper, we investigate the possibility of applying the theory of Monty Hall's paradox in tasks that require the need for an optimal choice of a strategy for developing the innovative potential of an enterprise. The article provides recommendations for taking into account and constructive use of the effects that affect the involved experts, in particular, the Condorcet principle and paradox. The paper explores the limits of applicability of the Monty Hall paradox theory. Its applicability is determined, together with considerations about the profitability of changing the initial choice in problems with the so-called "random intelligence".
Keywords: decision support systems, mathematical modeling, expert evaluation, Monty Hall's paradox, project management, collective assessment, Condorcet's paradox, enterprise management, assessment of enterprise characteristics
The modeling of a multi-motor linear electric drive of a conveyor train is considered. A diagram of the simulation model made in the Simulink program is given. Graphs of the speed and force of the electric drive during the relay transmission of the secondary element are given. The conclusion is formulated that the system fulfills the requirements placed on it.
Keywords: simulation modeling, Simulink, linear asynchronous motor, electric drive, conveyor train, relay transmission
Industrial enterprises place high demands on the quality of demineralized water, the economic feasibility of this process, as well as its environmental friendliness. The water treatment plant begins with pre-treatment, which allows the removal of dissolved suspensions, mechanical impurities and organic substances. Most often, the pre-cleaning process is organized using clarifiers. The type of clarifier used significantly affects both the efficiency of the process and its economic characteristics. The paper presents a comparative characteristic of the operation of vertical cylindrical clarifiers of the Central Research Institute, VTI and high-speed clarifiers with a pulsating column. The main operational characteristics are highlighted, and the cost of clarified water is calculated when using different types of clarifiers.
Keywords: clarifier, pre-cleaning, cleaning quality indicators, thermal power plants
The article presents a way to increase the load-bearing capacity of a reinforced concrete column due to metal clips from the corners with an increase in the load on it. To ensure the joint operation of the existing column and the metal cage, the corners are subjected to prestressing, which is achieved by compressing the corners with jacks.
Keywords: reinforced concrete column, column reinforcement, metal cage, prestressing of the cage
Concrete paving slabs for road construction are made from mixtures consisting of hydraulic binder, fine and coarse aggregates and water. The prepared mixture of a given humidity is subjected to vibration molding under the following technological conditions: process duration 5–10 seconds, vibration frequency 30–50 Hz and pressure 70–80 kg/cm2. Hardening of freshly molded samples is carried out in a heat and humidity treatment chamber. It has been established that it is possible to replace natural coarse aggregate with fractionated scrap concrete. The compressive strength of concrete with aggregate based on recycled crushed stone is 300 - 400 kg/cm2, water absorption 4.8 - 6.2%, frost resistance F2 200 - 300. The proposed technology allows solving both economic and environmental issues for regions with large amounts of concrete scrap at temporary industrial waste storage sites.
Keywords: concrete mixture, vibroforming, modifiers, filler, waste, concrete scrap, strength
This article deals with the problem of analyzing and recognizing human emotions using sound data processing. In view of the increase in the scope of application, which is largely caused by the difficult epidemiological situation in the world, the solution of the described problem is an urgent issue. The main stages are described: the audio data stream is recorded and, in accordance with the “sound fingerprinting” approach, is converted into an image that is a spectrogram of the sound data set. The stages of training a convolutional neural network on a pre-prepared set of sound data are described, and the structure of the algorithm is also described. To validate the neural network, a different set of audio data was selected, not participating in the training. As a result, graphs were constructed demonstrating the accuracy of the proposed method.
Keywords: neural network; human emotion recognition; convolutional neural network; sound fingerprinting; Tenserflow; Keras; Matlab; Deep Network Toolbox
Relevance and goals. The article describes a project in the field of solving the problem of managing organizational systems through the development of a system for remote monitoring and control of spatially distributed objects using LoRa network technology. Materials and methods. The project provides testing and practical use of LoRa networks. The developed system consists of 3 main modules: Devices, server part, and client application. In turn, devices are divided into gateways and end devices. Results. An automated system for managing spatial objects was designed, gateway devices and end devices that form a prototype of the Internet of Things network were developed and tested, as well as the server part of an automated system for remote control of spatially distributed devices. Conclusions. The system was tested and debugged, and a streamlined system for remote monitoring and control of spatially distributed objects was obtained based on the concept of the Internet of Things using LoRa network technology. It is assumed that the results of R&D will be in demand in organizations whose activities involve the use of spatially distributed resources.
Keywords: Internet of things, management of geographically distributed systems, LoRa networks, geosystem approach, spatial data infrastructures
In the article there was considered a possibility of off-grade materials utilization for making fine concrete with a multicomponent complex additive applied. Use of fine sands as raw material for fine concretes is actual for many regions in Russia because of deficiency of sands of necessary fineness modulus. There was considered the issue of utilization of fine sand and stale cement for reducing cost (loss), widening materials’ assortment for low-rise building, and energy- and resource-saving. To achieve the assigned purpose a multicomponent complex additive was applied. The research was carried out in full correspondence with the adopted design of the fractional factorial experiment. The acquired results were subject to a preliminary analysis and processing, and consequently dependences of strength properties upon varying factors were obtained. The obtained dependences made it possible to select optimal ingredients’ proportion of the complex modifying additive in order to increase strength properties of fine concrete based on off-grade materials. It was established that the use of optimal consumption of the complex additive components allows increase strength properties by 25-30% in comparison with the reference composition.
Keywords: fine concrete, fine sand, stale cement, complex additive, fractional factorial experiment, strength
This article presents a new developed calculation methodology, which includes provisions for standard calculations and takes into account the peculiarities of the operation of eccentrically compressed reinforced concrete structures operating at large eccentricities of load application. Adjustments have been made to the calculation methodology to take into account the following factors: the standard methodology uses the maximum tensile strength of reinforcement; proposals have been developed to determine the actual resistance of tensile reinforcement, which, in fact, will be significantly lower than the limit. Proposals are given that take into account the limiting deformations of concrete, which, in turn, will be a key quantity for determining the resistance of tensile reinforcement in the cross section. The article also presents the results of experimental studies of a flexible reinforced concrete pillar operating with a load eccentricity equal to e0 = 0.32h. Theoretical calculations and experimental studies were analyzed and appropriate conclusions were drawn.A formula has been developed to determine the real resistance of the stretched metal reinforcement at the time preceding destruction. The calculation algorithm has been compiled. When comparing theoretical and experimental strength, the difference did not exceed 5%.
Keywords: steel, heavy concrete, reinforced concrete, testing, stand