Search

The article provides methods for analyzing power consumption modes, discusses the main directions for improving the efficiency of economic incentives for the rational use of electricity with a tense energy balance during hours of maximum load of the power system and insufficient filling of the electrical load schedule at night, while improving the methods of economic regulation of accounting for electricity consumption, regulating electrical load schedules.

The article analyzes the use of direct voltage and current for electrolysis consumers powered by valve controlled converters, generating higher harmonics into the network, consuming reactive power fr0om the network and significantly affecting the quality of electricity and the efficiency of the entire power supply system.

This paper is about the use of tools of spatial analysis for assessing the natural conditions for recreational tourism in the mountains of Tashkent region. For this study maps of topography, landscape, and risks of avalanches are recompiled for the development of the database. Assessment is based on accepted criteria for evaluating the capacity of the region for recreational tourism. According to these criteria, the spatial analysis procedures were carried out. The general scheme of the GIS-based evaluation process is developed and tested. As the result of spatial assessment 5 major zones were identified. The result of the spatial analysis is the map that defines the spatial extent of suitable areas for short-term recreational tourism.

The dependence of the transparency coefficient of a five-layer two-barrier structure on the electron energy and the ratio of the widths of two neighboring potential barriers is calculated. It is shown that the extremum of the transparency coefficient significantly depends on the geometric dimensions of the structure layers. In a symmetric five-layer two-barrier semiconductor structure, the condition for the occurrence of "resonant" electron transitions is defined. It is demonstrated that the mechanism of such (resonant) transitions is explained by the interference of de Broglie waves of electrons in the potential well, where the phases of de Broglie waves are determined by the geometric dimensions of the structure, and their amplitudes - by the ratio of the carrier energy to the height of the potential barrier. It has been established that with an increase in the effective mass of charge carriers, the number of intersections of the quantities fR (ξ) and ((1-2ξ))/(√(ξ-ξ2) increases. These intersections determine the dimensionally-quantized levels where electrons are localized.

We have developed a theory of dimensional quantization for nanostructures, both one-dimensional and zero-dimensional, constructed from monoatomic layers of transition metal dichalcogenides (TMDCs). This theory has enabled us to derive expressions for the energy spectra of charge carriers in both even and odd states (relative to coordinate inversion), as these states occur within quantum-confined lines and points of the TMDC monoatomic layers, dependent on their geometric dimensions. Our numerical analysis provides a detailed exploration of the quantum-confined energy states of electrons within these nanostructures, offering insights into their potential applications in advanced nanoelectronic devices. This work not only advances our understanding of the energy characteristics of TMDC monoatomic layers but also contributes to the broader field of material science by exploring the effects of dimensional quantization on electronic properties.

A quantitative theory of two-photon linear-circular dichroism caused between the subbands of light and heavy holes of the valence band and conduction band is constructed, which takes into account the admixture of valence band states to the conduction band states and the temperature dependence of the band gap (Eg(T)) in semiconductors of tetrahedral symmetry in the multiband Kane model. It is shown that the type of oscillatory angular dependence or the amplitude values of the probabilities of two-photon optical transitions depend on the state of light polarization. This is due to the fact that, under the influence of linearly polarized light, alignment along the pulse occurs, and under the action of circularly polarized light, the moments of current carriers are oriented. It has been determined that the probability of two-photon optical transitions from the heavy hole subband to the conduction band of semiconductors at a fixed temperature increases with increasing frequency, passes through a maximum, and sharply decreases regardless of the degree of polarization of light, as well as the band gap.

The title compound, (C9H8NO)[CuCl3(C7H5NO4)]·2H2O, was prepared by reacting CuII acetate dihydrate, solid 8-hydroxyquinoline (8-HQ), and solid pyridine-2,6-dicarboxylic acid (H2pydc), in a 1:1:1 molar ratio, in an aqueous solution of dilute hydrochloric acid. The CuII atom exhibits a distorted CuO2NCl3 octahedral geometry, coordinating two oxygen atoms and one nitrogen atom from the tridentate H2pydc ligand and three chloride atoms; the nitrogen atom and one chloride atom occupy the axial positions with Cu—N and Cu—Cl bond lengths of 2.011 (2) Å and 2.2067 (9) Å, respectively. In the equatorial plane, the oxygen and chloride atoms are arranged in a cis configuration, with Cu—O bond lengths of 2.366 (2) and 2.424 (2) Å, and Cu—Cl bond lengths of 2.4190 (10) and 2.3688 (11) Å. The asymmetric unit contains 8-HQ+ as a counter-ion and two uncoordinated water molecules. The crystal structure features strong O—H...O and O—H...Cl hydrogen bonds as well as weak interactions including C—H...O, C—H...Cl, Cu—Cl...π, and π–π, which result in a three-dimensional network. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing involving the main residues are from H...Cl/Cl...H interactions, contributing 40.3% for the anion. Weak H...H contacts contribute 13.2% for the cation and 28.6% for the anion.

The article analyses the educational activities of Tatars, the emergence and development of printing and polygraphic production in Turkestan in the late 19th – early 20th centuries. The development of printing in the languages of the local Turkic population in Turkestan is associated with the socio-cultural and religious activism of Tatars. The author analyses historical and archival documents, a number of printed publications in the Uzbek language of the specified period and traces the logistics of the formation of printing culture in this region, which was significant for the Russian Empire. The article shows the effects of the modernisation trend among Tatars in the context of the scientific and technological revolution, and its transit through the Russian society to the foreign Turkic peoples of the country. The author describes the activities of Tatar typesetters who brought Muslim fonts for printing to the given region, thereby showing how the provision of a material and technical base stimulated the development of printing for the local Turkic-speaking population. The author demonstrates the development of the printing culture of Turkestan in the late 19th – early 20th centuries through the analysis of various aspects of the activities of such Tatar figures as Shakhimardan Ibragimov, Mukhammad Khasan Chanishev, Shakhingirey Bekkulov, Abdulatif Yaushev, Ali Bektemirov, Ismail Abidov, Arif Klevleyev, Akhmad Donskoy, and Shagid Akhmadiev. Along with that, the author analyses the participation of the Tatar intelligentsia in the development of printing activities and the establishment of printing in the new socio-political conditions that emerged after the revolution of 1917 – already in the Turkestan ASSR, in particular, in the Khorezm and Bukhara People's Soviet Republics.

This study investigates the kinetic properties of both symmetrical and asymmetrical multilayer and nano-sized semiconductor structures. We develop a theoretical framework using various models and mathematical methods to solve the Schrödinger matrix equation for a system of electrons, taking into account the Bastard condition, which considers the difference in the effective masses of current carriers in adjacent layers. We analyze tunnel-coupled electronic states in quantum wells separated by a narrow tunnel-transparent potential barrier. Our findings provide insights into the electronic properties of semiconductor structures, which are crucial for applications in micro- or nanoelectronics and other areas of solid-state physics.

Based on the results of the analysis of resistive circuits, a new circuit of an optoelectronic contactless voltage relay is developed in the article and its application in the power supply system is considered. The possibility of controlling the operating modes of various installations for amplifying electrical signals using optothyristors is presented and methods for their inclusion in electrical circuits are given. Optoelectronic contactless voltage relays were tested under laboratory conditions to obtain input-output characteristics and capacitance voltage waveforms. Based on the improvement of the proposed circuit, a circuit of an optoelectronic contactless voltage relay is developed and provides a high degree of reliability. The proposed voltage relay circuit is simulated using the Electronics Workbench and MATLAB R2014a programs, the results of which show that the changes in the shape of the output voltage curve are close to a sinusoid and coincide with the results obtained analytically.

In power supply systems the change in the magnitude of the voltage degrades the operation of electrical appliances right up to their failure. The proposed scheme of a contactless voltage relay based on a contactless voltage relay with switching the windings of a booster step-up transformer with a time delay allows switching the windings of a magnetizing booster transformer with a voltage change at the consumer terminals. Analytical studies of a non-autonomous non-linear dynamic circuit, which is the basis of the proposed device based on the classical method of solving a differential equation, which determines the nature of the voltage change for controlling thruster switches. The change of energy parameters of the proposed stabilizer depending on the voltage is given. The article considers the principle of operation of the proposed scheme of a contactless switching device based on a contactless voltage relay that switches the windings of a booster step-up transformer. An analytical study of a non-autonomous nonlinear dynamic circuit, which is the basis of the proposed device and the characteristics uc = f t required for switching the thruster is presented.

The article discusses the production and properties of two-dimensional atomic layers of transition metal dichalcogenides (TMDs), focusing on the optical properties of monolayers. It begins with an introduction to the discovery of graphene production methods and the subsequent interest in TMDs. The basic properties of TMD monolayers, their crystal structure, and Brillouin zone are detailed. The article explores the energy spectrum of electrons in different valleys and the effective Hamiltonian describing states in parallel spin bands. The discussion extends to the matrix elements of interband optical transitions, including single-, two-, and three-photon transitions. Equations are provided to calculate probabilities of optical transitions, incorporating factors such as polarization vector, frequency of light, and temperature of the sample. Theoretical analysis of constituent matrix elements for these transitions is outlined, emphasizing quantum mechanical aspects. The article contributes researching of the optical behavior of transition metal dichalcogenides (TMDs) monolayers, particularly in structures with complex compositions.

Digital twins, as virtual models of physical entities, are becoming vital in modeling various objects and phenomena in the modern world. In the agricultural sector, their role is particularly crucial, since digital twins facilitate not only the analysis of soil, climate, yield, and plant data but also the forecast of changes in these parameters. Accumulating and analysing vast amounts of information, digital twins help optimize the use of resources such as water, fertilizers, and pesticides, which in turn leads to increased yields and reduced costs. Moreover, digital twins enable the automation of many processes in agriculture, including the management of agricultural machinery and equipment. They provide the capability for more precise and efficient control of units such as tractors and combines, and also assist in predicting and preventing equipment failures, thereby reducing time and financial losses. (Research purpose) The paper aims to analyze software products used in the design and development of digital twins.(Materials and methods) The paper evaluates various software programs, selected based on their functionality range and compatibility with other systems.(Results and discussion) The paper assesses the effectiveness of each program in fulfilling its intended tasks. The provided examples highlight distinct features of each software type. Criteria for program selection were formulated. (Conclusions) The findings delineate the characteristics and functionalities of the evaluated software products, thereby determining their functional capabilities. Necessary requirements were defined to facilitate decision-making in selecting programs with similar functionality.

This study is devoted to the study of the solution of a boundary value problem for an ordinary linear differential equation of half order with constant coefficients. Using of the fundamental solution of the main part of the considered equation, we obtained the principal relations, from which we obtain the necessary conditions for the Fredholm property of the original problem. Further, using the Mittag-Leffler function, a general solution of the homogeneous equation is obtained. Finally, the problem under consideration is reduced to an integral Fredholm equation of the second kind with a non-singular kernel, i.e., the Fredholm property of the stated problem is proved.

In the title salt [systematic name: 4-(3-carboxy-1-ethyl-6-fluoro-4-oxo-1,4-dihydroquinolin-7-yl)piperazin-1-ium nitrate], C16H19FN3O3+·NO3−, proton transfer from nitric acid to the N atom of the piperazine ring of norfloxacin has occurred to form a molecular salt. In the extended structure, N—H...O hydrogen bonds link alternating cations and anions into [100] chains, which are reinforced by aromatic π–π stacking interactions between the quinoline moieties of the norfloxacinium cations.

В односвязных областях с гладкими границами рассматривается краевая задача типа задачи Пуанкаре для одного эллиптического дифференциального уравнения второго порядка, порождающего класс обобщенных гармонических функций. При достаточно общих предположениях относительно коэффициентов краевого условия рассматриваемой задачи устанавливается, что ее решение сводится к последовательному решению хорошо изученных интегро-дифференциальной краевой задачи Гильберта и дифференциальной краевой задачи Гильберта в классах аналитических функций комплексной переменной. Кроме того, определяются необходимые и достаточные условия разрешимости исследуемой задачи и доказывается ее нетеровость.

In the current economic environment, farms must respond to the challenges of the external environment and look for mechanisms to adapt and overcome the crisis, as well as diversify their business as additional sources of income. Therefore, the study of possible cross-sectoral adaptations of farms is a relevant research topic. Therefore, the purpose of this article is to provide a scientific basis for the predicates of diversification of farms' activities in overcoming the challenges of war. The study is based on classical approaches to management and marketing, as well as foresight predicates of agricultural development. The content of adaptation directions of farms' development was interpreted using empirical methods. The article analyses the sources of risks and threats, identifies targets and key aspects of the formation of intersectoral adaptation of farms: metrics, goals and foresight competences. As a result of the study of macro trends in the security of the agricultural sector, hypothetical analytical generalisations were formed, due to the uncertainty of the timeframe of the war and the impossibility of calculating the expected losses. Thus, the study made it possible to formulate theoretical and practical insights into the formation of adaptation mechanisms in the strategic perspective. The author substantiates the need for systematic and continuous monitoring of threats and invasions by systematising traditional and forecasting new risks. The key determinants of foresight adaptation under the influence of global trends are formulated. The mechanism of its implementation is presented through the identification of areas of intersectoral adaptation. The study is of practical value, generating information for farms, rural communities, stakeholders and potential investors who can benefit from the foresight of prospects and expectations formed in the context of cross-sectoral adaptation of farms in the post-war period

Purpose. The purpose of this study is to develop alternative scenarios for the development of rural tourism through the foresight methodology. Methodology / approach. Theoretical interpretations were formed by general scientific methods and approaches. To assess the prospects for the development of revitalisation of rural tourism, the method of scanning the horizon was used, which demonstrated the main tendencies and trends of the market and consumer tourism needs. Empirical methods made it possible to work out the stressors of systemic national crises, the global COVID pandemic, a full-scale war, which threaten the subjects of rural tourism with extraordinary losses and critical destruction of the material and technical base, losses of tourist interest – that is, questioning the existence of business as a whole. Therefore, an important task today is to draw up foresight scenarios and tactics that will create modules of investment attractiveness and mechanisms for the rapid accumulation of financial, architectural and construction, infrastructural and social potentials for the recovery of the economy of territorial units and the country as a whole. Results. Since forecasting is based on three “whales” (actual state, business experience and prospects), the foresight methodology is represented by tools with appropriate characteristics and management competencies. Therefore, in order to avoid complications and contradictions in the foresight of rural tourism, it is suggested to think over and install profiles of investment proposals, foresight scenarios for realising the possibilities of its restoration. Reasoned positions reflect the relevance of foresight research for assessing future prospects and opportunities for the restoration of rural tourism in Ukraine. The results of the study shed light on opportunities for rural development and suggest interventions to create a fully sustainable ecosystem. The study provides actionable information for rural tourism actors, stakeholders and potential investors who can benefit from forecasting the prospects and expectations emerging in rural tourism in the post-war period. Originality / scientific novelty. The scientific value of the research lies in the evaluation of the prospects for the development of rural tourism as a direction of diversification of the agricultural economy of Ukraine in 2019–2023 and the post-war period. A model for forming the investment profile of a rural tourism subject is proposed for implementation. Practical value / implications. The practical value of the research lies in the fact that it can be used as a tool for building effective cooperation in the development of plans and programs aimed at partnership relations with rural communities of Ukraine, tourism subjects, estate owners, etc. The value of this study lies in the foresight of rural tourism development prospects, which determine the competitive advantage of rural areas, with an emphasis on a relatively new and controversial topic after the war in Ukraine, namely its positioning in the structure of the restorative mechanism of regional development and tourism.