The most significant advantage of composite structures compared to structures made of traditional materials is the ability to control the characteristics of the structure in order to obtain an optimal design. In the general case, the initial physical characteristics of the material of the composite structure are random variables. Consequently, the required quantities (stresses, strains, critical loads, etc.) are also random variables. The problem of statistical modeling of a composite structure is ultimately reduced to the problem of transforming random variables. To solve this problem, the Monte Carlo method is used. The object of study is a multi-walled plate under the action of compressive loads. The purpose of this work is to construct point estimates of the coefficients of both general and local stability for a multi-walled plate, as well as to test statistical hypotheses about the equality of the stability coefficients to their theoretical values. The initial parameters are the elastic moduli in the longitudinal and transverse directions, as well as the shear modulus of the construction material. The following were used as output values: sample mean, standard deviation, skewness and kurtosis coefficients. All calculations were carried out in the environment of the MAXIMA package. It is shown that the distribution of the overall stability coefficient practically does not differ from the normal distribution. The coefficient of local stability has a slight positive asymmetry and a steeper peak compared to the normal curve. The results obtained allow us to conclude that the spread of the elastic characteristics of the material does not significantly affect the coefficients of the general and local stability of the multi-walled plate.
Keywords: statistical modeling, statistical hypothesis, multiwall plate, stability, critical load, composite material
The article is devoted to the use of renewable energy sources, namely geothermal energy for home heating. Methods of installation, advantages and disadvantages of geothermal heating are investigated. A comparative analysis of the cost of 1 MJ of heat received from various energy sources was carried out, and the efficiency of using heat pumps for heating buildings was proved. It was noted that in connection with the global problem of greenhouse gas emissions, this decision is relevant and paramount for achieving hydrocarbon neutrality. The introduction of geothermal heating methods can be a huge step towards green energy.
Keywords: system, temperature, geothermal heating, heat pump, compressor, evaporator, condenser, carbon footprint, ecology, green energy
The water sector in Syria suffers from longstanding problems and faces many challenges in terms of water supply and quality sanitation. These challenges include water scarcity, increasing water demand due to population growth and conflicts in the region, rapid urbanization, water pollution, limited access to drinking water and sanitation in rural areas, inefficient water distribution system in addition to constant network failures, as well as lack of financial resources, inefficient water pricing system and methods, cost recovery and asset management. As a result, the need for a significant quantitative increase and qualitative improvement of engineering infrastructure facilities (water supply and sanitation systems) and parts of distribution networks, in addition to the technical capabilities and development of resource management methods, which in turn leads to improved management of water supply and sanitation systems and the welfare of the population in the region, clearly becomes apparent.
Keywords: water supply and sanitation systems, Syrian Arab Republic (SAR), reconstruction, consequences of military operations, urban planning
A model of interaction between a railway and a seaport has been developed in the presence of a governing body. Interaction functions are described for the proposed model, analytical solutions for the static model are found, and the simulation speed is compared without and with the use of analytics. Next, a dynamic model is considered and an algorithm for finding an equilibrium for this model is proposed. The subsequent use of parallel programming methods will make it possible to plan interaction in this model to a better extent.
Keywords: mathematical model, simulation modeling, Stackelberg equilibrium, hierarchical game, mixed transportation, railway transport, port
For prototyping virtual resources, there are modern UI/UX development applications that have the means to build highly productive interaction algorithms, for example, Figma or its promising new competitor Pixso. These programs support the joint redating of projects, and also allow planning and discussion of ideas and stages of work here, in the environment. The correctly chosen method of interaction leads to a multiple increase in productivity. One of the recognized approaches to project planning and management is the Agile design methodology.
Keywords: team, layout, prototype, website, methodology, formal language, brainstorming, frame, project, interface, plugin, editor
The work is devoted to the problems of strategic planning in the digital technology market. The aim of the work is to build a decision support procedure for choosing a strategy, based on internal (related to the characteristics of the firm choosing the strategy) and external (conditioned by the state of the market) factors. It is assumed that the elementary strategy is described by the type, direction and applied area of activity. In this case, the possibility of combining several elementary strategies is considered. The main result of the work is a procedure for choosing a combined strategy based on the application of a genetic algorithm. The use of the methodological apparatus of evolutionary calculations is due to the large number of possible options for combined strategies and the complexity of their evaluation, which makes a complete enumeration of options impractical. The final choice is made by the decision maker based on their own preferences.
Keywords: IT market, decision support, genetic algorithm
The article presents the study results of a soil-like fraction contamination at a landfill located on the territory of the Traktorozavodsky district of Volgograd with heavy metals. The soil-like fraction's pollution level was assessed using a cumulative chemical pollution index (Zc) and its modifications. It was determined that the contamination levels with heavy metals are dependent on a used cumulative chemical pollution index modification. The use of the average geometric values of a cumulative chemical pollution index (Zc) is preferred for a pollution assessment of a soil-like fraction. Because the pollution level of a studied soil-like fraction was assessed as hazardous, its use as a recultivation material can only be permitted after a detoxification.The main pollutants in the soil-like fraction are cadmium, copper, and nickel.
Keywords: landfills, soil-like fraction, heavy metals, pollution level
The algorithm and code listing of the developed self-learning chatbot are presented. Able to maintain a conversation with the user, switch to training mode in the absence of the necessary information, analyze the context of the conversation for "forbidden" words. The Trim function is used, which removes extraneous characters represented in the tr property. And also an additional option "Solve arithmetic problems" is implemented in case of a request from the user. When implementing the latter option, a recursive descent algorithm based on three nested recursive functions was used, while the binary tree is filled in. A function has been developed to divide the incoming string into tokens. The chatbot code is developed in C++/C# based on the principles of object-oriented programming with the development of classes.
Keywords: artificial intelligence, machine learning, voice assistant chatbot, learning mode, tokens, recursive descent, binary tree
The article confirms the need for a systematic approach to the scientific justification of the electronic document management systems security(EDMS) and the relevance of the study, presents the results of the analysis of guidance documents regarding the development of mathematical models and existing experience, summarizes the procedure for the scientific justification of EDMS security, highlights the main trends in modeling today, a new approach to the construction of EDMS security models is proposed, defines its role and place in the existing theory and practice.
Keywords: Security models of computer systems, security policy, electronic document management system, systematic approach
Despite the existing differentiation of the regions of the Russian Federation in terms of natural and climatic conditions and the level of socio-economic development, the main principle of the state cadastral valuation is aimed at the uniformity of its implementation. The study in this paper is aimed at revealing the concept of "regional features" as a factor leading to a discrepancy in the methodology for determining the cadastral value of real estate at the regional level. The article highlights the factors of regional specifics that form the features of the appraisal work to determine the cadastral value of land plots in 2022 on the territory of St. Petersburg and the Perm Territory, as well as recommendations for improving the existing unified methodology.
Keywords: state cadastral valuation, mass valuation, taxation, cadastral value, market value, differentiation of regions, regional peculiarity, real estate object, land plot
The article describes ways to equalize temperature differences in the material after preheating in the heating zone. A mode for changing the temperatures of the material and the furnace channel has been developed. The optimal length of the firing zone and the time of passage of the material were established, at which a constant temperature is maintained on the surface of the material. Values for optimizing the main parameters are given.
Keywords: firing, tunnel kiln, temperature equalization
The article considers a formalized data model of a software package for automating the accounting of the activities of an animal care center, which includes two subsystems: "Subsystem of information support for the activities of a shelter for homeless animals" and "Subsystem of automation of accounting for the activities of a hotel for animals". The formalized model allows you to structure the subject area, highlight the main components, their properties and relationships between them (customers, pets, aviaries, booking requests, volunteers, tasks, etc.), which was later used for algorithmization of the solution and software implementation of complex tools on the 1C:Enterprise platform.
Keywords: formalized model, animal shelter, homeless animals, hotel for animals, 1C:Enterprise, automation, activity accounting, animals, software package, information system
The development of an automatic system for installing a magneto-optical magnetic field sensor in a neutral position has been carried out. Installation in the neutral position is carried out by an automatic piezoelectric drive control system based on a microcontroller. A mathematical model is constructed and numerical simulation of the automatic control system is performed. The results and parameters of the simulation are presented. The developed system provides a significant increase in the autonomy of the sensor, which makes it possible to eliminate or significantly reduce the cost of regulating the sensor.
Keywords: magnetic field sensor, magneto-optical sensor, automatic control system, piezo motor
An example of a technical examination of a cultural heritage object of federal significance is given in order to identify the fact of violation of the Federal legislation during its restoration. Recommendations are given on the preparation of a technical conclusion of this examination. The article was written on the basis of the research carried out (at the request of law enforcement agencies).
Keywords: technical expertise, object of cultural heritage, violation of the law, building structures, temple, dome, restoration
Noise pollution of the air is considered to be an excess of the natural level of the background noise or a sharp fluctuation and change in such sound characteristics as the frequency of the sound wave and the strength of the sound stream. The article considers noise levels in the mainline territories in a linear city.
Keywords: linear city, traffic noise, highways, air environment, landscaping, equivalent noise level, row of planting, arboretum composition