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  • Database of wooden architecture objects of Karelia

    The article considers the issues of developing a database of wooden architecture objects in Karelia. The database includes 1009 attributed photographs obtained as part of the comprehensive expedition of the Ministry of Culture of Karelia in 1979-1980 and the comprehensive expedition to Syamozerye in 2000-2001. The expedition research was carried out by specialists and students of Petrozavodsk State University under the supervision of Academician Vyacheslav Petrovich Orfinsky. The database was developed in the MySQL database management system. The database scheme is provided, the tables are described, and an example of a photograph with attributes is presented. The database allows storing and editing materials from historical and architectural expeditions and research by employees of Petrozavodsk State University, as well as searching for photographs of wooden architecture objects in Karelia by various criteria, including date, location, type of object, and author.

    Keywords: wooden architecture, database, expeditions, MySQL DBMS, photographs of wooden architecture objects

  • Development of fine heat-insulating concrete mix on granulated foam glass

    Toughening of requirements to buildings’ power efficiency enables development and implementation of modern lightweight concretes on efficient porous aggregates into building industry. The key demands to both lightweight heat-insulating and to fine concretes are ensuring low density index and thus low thermal conduction with high durability provided. There has been developed a lightweight heat-insulating fine concrete mix with the use of three fractions of granulated foam glass. To conduct the research there has been used a central composite design, which helped determine optimal consumption of separate fractions of granulated foam glass, and acquire a lightweight heat-insulating fine concrete with the lowest density. On the basis of obtained research results there has been carried out a calculation of thermal conduction ratio with the use of empirical formulae. The research results have been analyzed, and their descriptive statistics have been presented as diagrams and graphs. On the basis of the analysis of the research results there have been obtained regression equations and established influence degree of separate fractions of granulated foam glass on the density and thermal conduction ratio. There has been carried out an optimization of the material mix and the correlation between fine aggregate fractions calculated to provide the lowest average density.

    Keywords: fine concrete, granulated foam-glass, thermal conduction ratio, average density, durability, experiment design, regression, mix optimization

  • Traditions and innovations in the architecture of public centers in the Republic of Yemen

    The article is devoted to the study of the evolution and current situation of the architecture of community centers in the Republic of Yemen. The main stages of the development of the typology of community centers related to historical events that influenced a number of changes in Yemeni society are consistently considered. A comparative analysis of traditional and modern solutions of Yemen's community centers has been carried out: functional planning, spatial and spatial solutions, architectural facade solutions, structures and materials. The problems associated with the loss of traditional Yemeni solutions in modern architecture have been identified. The conclusions are recommendations on the formation of community centers, taking into account the synthesis of cultural traditions and foreign trends, in order to achieve an international level of service and meet the current needs of the population.

    Keywords: Republic of Yemen, architecture, community center, typology, social structure, traditions, innovations

  • The use of activated rubber chips in the reconstruction of the upper part of overpasses and the roadway of bridge structures

    Intensive wear of the road surface under the influence of traffic loads, climatic factors and structural features of bridges has increased the number of studies in this area. One of the promising areas for improving the operational reliability of bridge structures is filling asphalt concrete mixtures with activated rubber chips, which are highly resistant to wear and mechanical damage. Both traditional paving technologies using polymer-composite mixtures and modern technologies using asphalt concrete filled with activated rubber chips are considered. The advantages of using recycled rubber, which increases the traction properties, wear resistance and durability of the road surface, are considered. A comparative calculation of the cost of pavement reconstruction using the compared technologies was carried out, which showed a significant reduction in the cost of materials and laying asphalt concrete with activated rubber filler compared with polymer composite coatings.

    Keywords: activated rubber chips, asphalt concrete, reconstruction of overpasses, road surfaces, wear resistance, traction properties, economic analysis, polymer composite coatings, technological process, recycled materials

  • Intensification of the mixing devices operation during contact coagulation of natural waters from surface sources

    Analytical dependences have been obtained that make it possible to assess the influence of various factors on the degree of enlargement of microflakes formed in the thickness of the coarse-grained load after the introduction of coagulant. To assess the intensity of the coagulation process, the values of the mixing rate gradient were obtained depending on the filtration rate of coagulated water in a coarse-grained load. Graphs are also provided that establish the dependence of the mixing rate gradient depending on the filtration rate of coagulated water in a coarse-grained load. A scheme of coagulation treatment of natural water using a contact chamber with coarse-grained loading and receiving concentrated coagulation is proposed, which is recommended for intensifying the operation of typical hydraulic mixers of water treatment plants and reducing the required doses of coagulant.

    Keywords: contact coagulation, natural water, mixing devices, mixing rate gradient, filtration rate

  • Multidisciplinary research

  • Development of a circuit with pulsating circulation of liquid coolant in the circuit of a plate heat exchanger

    A laboratory circuit of the installation with a heat exchanger-supercharger in the hot water circuit of the boiler has been developed. The conducted studies have shown that the temperature of hot water at the outlet changes depending on the oscillation frequency of the electromagnetic valve at a given flow rate, and the highest efficiency of water heating is observed at a frequency of 1.75 Hz. Calculation of the heat transfer coefficient showed that at a steady-state flow rate, the heat transfer coefficient of the heat exchanger-supercharger is 180 W / (m ^ 2 ° C). Then, with increasing frequency, the heat transfer coefficient smoothly decreases and reaches a minimum of 173 W / (m ^ 2 ° C) at 1.0 Hz. With a further increase in frequency, the heat transfer coefficient begins to increase and reaches a maximum of 188 W / (m ^ 2 ° C) at 1.75 Hz. As a result of the experiment, it was also found that with increasing frequency, the flow rate in the hot water circuit increases and reaches a maximum at a frequency of 1.75 Hz Q = 0.6 l / sec. That is, at such a frequency, the heat exchanger-supercharger, due to the oscillations of the liquid flow in the first circuit (cold water circuit), most effectively transmits the oscillations of the flow to the second circuit (hot water circuit), which can be used to reduce the power of the pump in the hot water circuit at this frequency.

    Keywords: heat exchanger-supercharger, heat transfer coefficient, electromagnetic valve, water hammer

  • Modification of the regional Solow model for the developing control of the districts of the subsidized region using the example of the Republic of Kalmykia

    In the article a modification of the socio-ecological-economic model of regions within a macroregion to a network model of districts within a subsidized region is built, taking into account the distances between them that affect the economic relationships of the regions. Structural identification of the model parameters is carried out using the example of data from the Republic of Kalmykia of the Russian Federation. The aim of the research is to build the region hierarchy model to analyse that control the district developing to maximize gross regional product. To do this, some relations of the Solow model were reconsidered and some functions were rebuilt including birth and death coefficients. The influence on gross regional product of Innovative index was also investigated and the value of Republic of Kalmykia is found. Network structure taking into account distances between the districtd is included into the model.

    Keywords: network model, structural identification of parameters, subsidized region, payoff functions, economic interrelations of regions, birth rate, death rate, innovation index, fixed assets, labor force, final product, gross regional product

  • Processing of measurement information from an eddy current sensor during localization of defects in the surface layer of bearing parts

    The problem of determining the area of defects in the surface layer of bearing parts according to eddy current non-destructive testing is considered. Methods of processing eddy current control data are given. The possibility of using a robust median polishing method to increase the information content of eddy current data is substantiated. It is proposed to use a sliding window, a standard deviation calculation, and a production rule formed by the Shannon information entropy criterion as tools for localizing defect patterns in the eddy current image of the control object. The results of the application of the developed localization algorithm based on eddy current control data of bearing parts obtained in real production conditions are presented.

    Keywords: eddy current control, localization, defect, data analysis, recognition, surface layer, intelligent technologies, Shannon entropy, median polishing, classification problem

  • Theory and practice of hydro-, pneumo- and thermochemical studies of an industrial burner with combined intensification of combustion of C-H-O-containing fuels

    A combined theoretical and practical study of the burner device parameters has been performed. The flow characteristic of the fuel supply system has been determined. Aerodynamic studies of the burner device characteristics have been conducted, axial velocity fields have been constructed, and critical parameters of the air supply unit design have been identified. The temperatures of in-chamber processes have been experimentally determined. A mathematical model of chemical reactions of the torch has been developed, and the dependence of diesel fuel toxicity on the excess air coefficient has been constructed. The effect of water vapor on the burner device operation has been determined.

    Keywords: burner device, axial velocity field, intra-chamber processes, thermochemical parameters, mathematical modeling, toxicity

  • Analysis of oculography data using an adaptation of the velocity threshold identification algorithm to study the influence of black color of objects on visual attention prioritization

    The term "oculography" (eye tracking) describes a technological method used to record eye movements in real time. This technique allows researchers to analyze the focus of subjects' attention on various interface elements. Color is a powerful tool for attracting attention. Understanding which colors first attract attention allows marketers to correctly place accents on visual stimuli, such as advertising materials that feature clothing of different colors, in order to improve the experience of interaction of a potential consumer with this content. The purpose of this work is to determine the effect of the black color of clothing on the priority of human attention. To achieve this goal, experiments were conducted in which the gaze of subjects was tracked using a webcam while they studied an experimental image. The analysis of the final experimental data obtained using the adapted velocity threshold identification algorithm showed a high attention priority for the black color of clothing. In 87.5% of cases, attention was paid to it first, while the gender of the subject did not play a significant role in this perception. The obtained results can help in the development of research aimed at improving the efficiency of information perception.

    Keywords: oculography, velocity threshold identification algorithm, eye tracking technology, attention priority, region of interest, time to first fixation, advertising, clothing, color

  • Surveying support of the stages of preparation of the earth's surface for the construction of a bush site

    The article considers the sequence and technology of conducting surveying before starting excavation work on a bush site for the oil and gas industry. Surveying works play a key role, ensuring the necessary accuracy and reliability of the development of oil and gas fields. These works include conducting field measurements, detailed terrain analysis, calculating the volume of soil masses involved in the construction of earthworks, as well as monitoring geometric parameters and sand pits. An important stage of surveying is the creation of a detailed topographic map of the territory. Based on this map, it is possible to accurately plan the location of all future structures, ensuring optimal use of space and compliance with all regulatory requirements. The use of modern technologies, such as geodetic GPS systems and BIM technology, can significantly improve the accuracy and efficiency of these works. Special attention is paid to compliance with industrial safety standards, which minimizes costs and risks in the development of oil and gas industry enterprises. Thus, surveying is an integral part of the preparation and implementation of projects in the oil and gas field, contributing to the efficient and safe performance of all necessary work.

    Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production

  • Improvement of the methodology for calculating protection of structures of residential buildings against explosive effects of UAVs

    The study is devoted to improving the methodology of calculation of structures for the impact of explosive loads, including aerial shock waves in UAV attacks. Modern modeling methods are analyzed, a calculation algorithm using non-linear dynamic approaches is proposed. It is shown that the use of spherical discrete elements allows a more accurate assessment of debris destruction and formation. The calculations presented confirm the effectiveness of the proposed approach.

    Keywords: Explosive loads, air shock wave, unmanned aerial vehicles, dynamic calculation, destruction of structures, simulation of explosive effects, application of spherical discrete elements, calculation algorithm, formation of debris, non-linear methods

  • Numerical methods for parameter estimation of Generalized Autoregressive Conditional Heteroskedasticity models of financial time series

    This article discusses numerical methods used to estimate the parameters of a family of Generalized Autoregressive Conditional Heteroskedasticity (GARCH) models, which are widely used for analyzing and predicting financial time series with variable variance. The paper provides a comparative analysis of numerical methods for estimating GARCH effects, which are based on the gradient descent method of adaptive algorithms, various variations of quadratic methods based on the Newton method, as well as alternative methods based on the simplex method, linear and quadratic interpolation. The analysis is carried out on the basis of synthetic data and on real data on quotations of the Moscow Exchange stock index using the Python 3 programming language and libraries scipy, numpy, matplotlib and others. The results of the study show that the specifics of the financial time series problem are sensitive to the choice of numerical methods for solving the optimization problem of maximizing the likelihood function. Numerical experiment has shown that using the Nelder-Meade method to evaluate GARCH effects gives the best results for solving the problem of maximizing the likelihood function.

    Keywords: mathematical modeling, numerical methods, maximum likelihood method, gradient descent, Newton's method, mathematical modeling, GARCH, time series, stock market, news flows

  • Organizational and technological approaches to mathematical modeling and forecasting of construction site accident risk

    This article discusses effective ways and means for analyzing the condition of real estate objects, as well as predicting changes in their operational properties over time. These approaches open up prospects for improving the accuracy of predictions of wear patterns of both physical and functional components, as well as the aging of building structures, structures and engineering systems. Ultimately, this helps to maintain the proper level of their work and ensure high-quality functioning. Considerable attention is also paid to the general kinetic theory of structural wear of construction facilities, as it is known that this theory makes it possible to assess the corresponding reliability risks with fairly high accuracy, depending on the service life of the building structures of the facility. As a research tool, it is proposed to use a universal mathematical model of wear, which illustrates the dynamics of the processes of structuring and destruction of building systems throughout their entire service life. The model reflects the constant interaction of the structure with long-term impact factors. A statistical model has also been developed to determine the probability of the transition of building elements to a state of destruction due to the influence of adverse factors, which is directly related to the loss of their reliability.

    Keywords: organizational and technological solutions, reliability, quality control, efficiency, cost, labor productivity

  • Simulation of the process of long-mandrel drawing of profile pipes

    A finite element model of the deformation zone during cold drawing on a movable mandrel has been developed and justified. This makes it possible to determine the state of the metal, calculate its damage and the shape of the die channel, while the configuration of the first transition is taken as the initial one to obtain the second transition.

    Keywords: Simulation of the process of long-mandrel drawing of profile pipes

  • Approaches to optimizing the production process management system at the enterprise

    Finding ways to improve the efficiency of the production process at precast concrete plants is a relevant area in production management. It is necessary to take into account the specifics of the entire production process. Identifying opportunities to improve the production process management system is critical for any organization seeking to increase efficiency, reduce costs, and improve overall productivity. Production process management involves taking into account many variables, such as labor, equipment, raw materials, workflow, and more. Production management is aimed at optimizing production and finding a balance between the quality and productivity of manufactured goods, as well as the time and resources spent on their production. When studying ways to improve the production process, managers focus on two key parameters: productivity and product cost. When setting goals to reduce costs and increase productivity, managers must take into account these closely interrelated elements. But despite the obvious connection between productivity and cost, attempts to improve these parameters are often made separately. The purpose of the article is to identify approaches to optimizing the production process management system at an enterprise. The study is practically significant due to the fact that the development of approaches to optimization of the production process management system at the enterprise will help to use these approaches in the production process management system.

    Keywords: enterprise, production process, management system, approaches, optimization

  • Reports on current research

  • Formation of tables for a preliminary assessment of the bearing capacity of a centrally loaded masonry wall with elastic characteristics of 1000, 1200 and 1500

    The article presents the results of a study aimed at forming tables for a preliminary assessment of the load-bearing capacity of a running meter of a centrally loaded wall of various thicknesses, heights and strengths made of masonry with elastic characteristics α = 1000, 1200, 1500.The results of calculating 540 different variations of a centrally loaded stone element with different types of stone and mortar material are analyzed. The results of the study make it possible to exclude the use of a software package for preliminary determination of the bearing capacity of a centrally loaded stone structure and can become part of a practical guide for engineers involved in the technical inspection and design of masonry structures.

    Keywords: bearing capacity, wall, stone structure, elastic characteristic of masonry, centrally loaded element, stone, brick, block, masonry mortar, coefficient of longitudinal bending, flexibility

  • Nuclear power station cooling systems

    Review of fresh patents on nuclear power station cooling systems and current problems & future of nuclear power stations.

    Keywords: nuclear power station, cooling systems, patents

  • Machine learning methods for automatic document processing

    The work is devoted to the analysis of machine learning methods for solving problems of automatic document processing. The study considers such methods as classification, information extraction, pattern recognition and natural language processing and their application in the analysis of text data. An analysis of existing algorithms and models, including linear models, decision trees, support vector methods, and a comparison of their effectiveness depending on various conditions and parameters is carried out. Particular attention is paid to the problems that specialists face when using machine learning methods in working with documents, such as data quality, the need for pre-processing and tuning of model parameters. Prospects for further research in this area and examples of possible integration of modern machine learning methods to improve the efficiency and accuracy of automatic document processing in various industries are given.

    Keywords: machine learning, automatic document processing, computational experiment, artificial intelligence, classification models, software package

  • Methods of applying radio-absorbing coatings

    Radio-absorbing coatings are becoming increasingly relevant in the context of the rapid evolution of radio communication technologies and the fight against electromagnetic interference. Modern methods of applying RPP, their advantages and disadvantages, as well as prospects for the development of technologies are considered.

    Keywords: electromagnetic radiation, thin films, coating technology, radio-absorbing coating, radiation shielding

  • Investigation of the microhardness characteristics of a deposited layer formed by supersonic gas-powder technology

    In the course of the conducted studies, the microhardness of both the base metal and the boundaries of the fusion and deposited protective coating were evaluated. Attention is paid to the factors influencing the microhardness level depending on the height of the protective coating of the sample. To visualize the collected data, diagrams were created illustrating the distribution of microhardness in the source material and the protective layer obtained using supersonic gas-powder surfacing.

    Keywords: deposited layer, supersonic gas-powder surfacing, fusion boundaries, microhardness

  • Robotic demonstration training using a diffusion model and reinforcement learning algorithms

    The paper proposes a two-stage method of training a robot based on demonstrations, combining a diffusion generative model and online additional training using the method of Proximal Policy Optimization. In the offline phase, the diffusion model uses a limited set of expert demonstrations and generates synthetic "pseudo-demonstrations", allowing to expand the variability and coverage of the original dataset. This eliminates the narrow specialization of the strategy and increases its ability to generalize. In the online phase, a robot with a pre-trained strategy adjusts its actions in a real environment (or in a high-precision simulation), which significantly reduces the risks of unsafe actions and reduces the number of necessary interactions. Additionally, parametrically efficient pre-tuning has been introduced, reducing computational costs for online learning, as well as value guidance that focuses the generation of new data on areas of states and actions with high Q scores. Experiments on tasks from the D4RL set (Hopper, Walker2d, HalfCheetah) show that our approach achieves the greatest accumulated reward with lower computational costs compared to alternatives. T-SNE analysis indicates a shift of synthetic data in the area of space with high Q scores, contributing to accelerated learning. The results obtained confirm the prospects of the proposed method for robotic applications, where it is important to combine the limited volume of demonstrations, the safety and effectiveness of the online phase.

    Keywords: robot learning from demonstrations, diffusion generative models, reinforcement learning, Proximal Policy Optimization

  • An overview of the use of large language models in information tasks of decision support systems using the example of healthcare

    The article is devoted to the application of large language models (BMS) in information tasks of decision support systems using the example of healthcare. The key BAYAM architectures and their practical implementations are considered, as well as the capabilities of these models for natural language processing and medical data analysis. Special attention is paid to the role of BAM in automating decision-making processes, including optimizing access to knowledge from clinical recommendations. Examples of the use of BYAM in various fields of medicine are presented. In addition, the prospects for further development of BYAM in healthcare and related challenges are discussed.

    Keywords: big language models, natural language processing, decision support systems (DSS), industrial engineering, clinical guidelines, international classification of diseases