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Бюллетень науки и практики @bulletennauki
Статьи журнала - Бюллетень науки и практики
Все статьи: 6993
Research of indicator analysis of social and economic security
Статья научная
The thresholds represent the subsequent specification of the state interests in the field of socio-economic security risks. They say these aspects of socio-economic security of food, energy, infrastructure, technology, etc. To a significant extent there are recognized difficulties of life support. In this group are required to enter threshold values, characterizing the danger, located on the border between socio-economic and other characteristics of a security, for example, demographic, industrial security, available strategic reserves etc. The more difficult is the question of the quantitative parameters of threshold values. It must be said that the development of methodological approaches to the determination of such quantitative characteristics has proved to be a difficult task, taking into account that there is a very strict criticism about the quantitative characteristics of the thresholds. It is possible to agree with such arguments against the quantitative calculation of thresholds as their lack of real-specific orientation, the controversy of the methods of calculation used, etc.at the same time, the threshold indicators are a real signal of a positive or negative position, a team to the action of the relevant state bodies.
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Статья научная
The ship’s central cooling water system is one of the most important systems serving the main engine. With the progress of society, the design and construction of ships increasingly need to develop in the direction of environmental protection and energy-saving. Taking the 59,990 t bulk carrier as the research object , this paper proposes that based on the frequency conversion control of the seawater pump and supplemented by the energy-saving scheme of pulsation enhanced heat exchange, the frequency conversion control of the seawater pump is realized by adjusting the speed according to different working conditions. At this time, adding pulsation enhanced heat transfer technology can generate forced convection, increase the turbulence of the fluid in the tube, and introduce convection into the boundary layer, and at the same time produce cavitation, which can improve the heat transfer efficiency of the equipment. After using the seawater pump frequency conversion control and pulsation enhanced heat exchange program, the energy consumption is about 36% of that before the system was installed. The data shows that the program achieves the purpose of environmental protection and energy-saving and has a certain reference value for engineering research.
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Research on modeling and simulation of doubly fed induction wind turbine based on MATLAB/Simulink
Статья научная
This paper first introduces the structure of doubly fed wind power generation system and the working principle of doubly fed induction generator in detail and establishes the corresponding mathematical model of doubly fed wind power generation unit. The control part of wind power generation system based on doubly fed induction generator includes rotor side control and stator side control. The rotor side control adopts the vector control strategy based on stator flux orientation of the double-fed induction generator connected to the grid, and the working principle is analyzed in detail, and the main part of the simulation modeling is given. Stator side control adopts vector control strategy of grid-connected inverter control, and its working principle is analyzed in detail, and the main part of simulation modeling is also given. In order to verify the correctness and feasibility of the system, the simulation experiment platform of doubly fed wind turbine under this control strategy is built by using Matlab/Simulink simulation platform, and its simulation analysis is carried out in detail.
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Research on ventilation and heat dissipation performance of trailer power station
Статья научная
The results show that the use of CFD software to simulate the ventilation and heat dissipation of the trailer power station cabin, Get the flow field and temperature field in the cabin, The position of the highest temperature in the vehicle cabin can be determined quantitatively, which provides a useful reference for the design of the cabin structure of the trailer power station and the arrangement of the equipment in the vehicle. Moreover, the simulation results are in good agreement with the experimental results. It shows that the selected Realizable k-ε Turbulence Model can more accurately simulate the air flow field in the cabin of the trailer power station. It also shows that the model simplification method used in the calculation and the setting of analytical conditions are reasonable.
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Research progress of p-type cuprous oxide in the field of light energy utilization
Статья обзорная
Cuprous oxide (Cu2O), as a representative intrinsic p-type inorganic semiconductor material, has been widely used in the field of optical energy utilization, such as photovoltaic, photocatalysis, photodegradation and other fields, and has an extremely important position. For a long time, the literature on Cu2O’s application technology in the field of light energy utilization is relatively scattered and independent, resulting in a certain degree of obstacles and difficulties to obtain relevant technical knowledge and have a deep understanding of its internal principles. According to the application of Cu2O in the field of light energy utilization in recent years, it is mainly divided into three modules (photovoltaic, photocatalysis, photodegradation), and mainly summarizes the classification, principle and characteristics of Cu2O application in the field of light energy and prospects the optimization method and development direction of the application in the field of Cu2O light energy. This review aims to provide reference and guidance for the optical energy applications of Cu2O and other related inorganic oxide semiconductors.
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Research progress of type P copper (I) oxide in the field of light energy utilization
Статья обзорная
Copper (I) oxide Cu2O, as a representative intrinsic P-type inorganic semiconductor material, has been widely used in the field of optical energy utilization, such as photovoltaic, photocatalysis, photodegradation and other fields, and has an extremely important position. For a long time, the literature on Cu2O’s application technology in the field of light energy utilization is relatively scattered and independent, resulting in a certain degree of obstacles and difficulties to obtain relevant technical knowledge and have a deep understanding of its internal principles. According to the application of Cu2O in the field of light energy utilization in recent years, it is mainly divided into three modules (photovoltaic, photocatalysis, photodegradation, photodegradation), and mainly summarizes the classification, principle and characteristics of Cu2O application in the field of light energy and prospects the optimization method and development direction of the application in the field of Cu2O light energy. This review aims to provide reference and guidance for the optical energy applications of Cu2O and other related inorganic oxide semiconductors.
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Results of Introduction of Jasminum sambac in Absheron
Статья научная
Bioecologıcal features, propagation methods root system and agrotechnics of Arabian jasmine (Jasminum sambac) which belonging to Lian group plants have been presented in the paper. The light-loving Arabian jasmine plant is grown in shaded conditions, yellowness is observed on the shoots, which leads to growth retardation have shown in results of studies. The studies were carried out in various conditions — in the shadow, on light, under the sun. In plants grown in the shade in the summer (July-August), the growth of the main shoot was not observed, compared with plants grown in direct rays in January-February, which, had growth in contrast to them, Highest results were obtained in August using green cuttings under studying of the reproduction of Jasminum sambac. No diseases have been observed in these plants, but they were susceptible to pests such as Aphidoidea, Diaspididae and Aleyrodidae during the research. Bioecological features of species, easily propagation by vegetative way, decorative appearance throughout the year allow us to use them design of interiors with plants has revealed.
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Статья научная
Since 2006, with the support of WWF (World Wide Fund for Nature) and IDEA (International Dialogue for Environmental Action), remote research of leopards ( Panthera pardus saxicolor , Pocock, 1927 = P. p. ciscaucasica , Satunin, 1924). The main research is carried out on the eastern slopes of the Zangezur Mountains in the Aliyev Zangezur National Park of the Nakhchivan Autonomous Republic of Azerbaijan. To study the leopard, photographic traps of the Cudde Back (17 pieces), Panthera (5 pieces) and Bushnel (64 pieces) brands in the amount of 86 pieces are used. In 2019 alone, 373,622 photos and 45,553 videos were taken. On 340 photos and 71 video materials, adult leopards were recorded, and on 20 photos and 5 video materials, a female leopard with cubs was filmed, and a photo of a female and a male was found on 7 photos and 4 video materials. During this period, 12 adults and 3 calves were identified.
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Статья обзорная
The article indicates the results of paleobotanical research in the territory of the Nakhchivan Autonomous Republic of Azerbaijan. Materials for fossil plants in the territory Nakhchivan Autonomous Republic show that the development of the Mesophytic era covers the Permian, Triassic, Jurassic, Cretaceous, during which existed Neomesophyte and Palaeomesophyte flora. Cenophytic era covers Paleogene, Neogene and Quaternary period. Flora of Nakhchivan Autonomous Republic relates to Mesophytic and Cenophytic era. Modern vegetation of the region is dominated by open and semi-open coenosis i.e. rather primitive in its phytocenotic essence. These xerophilous coenosis have deep ancient roots of its origin. Flowering flora originated on the globe in the first half of the Cretaceous period. The oldest plant residues, which are known in Nakhchivan Autonomous Republic, refer to the end of the Cretaceous period. Found that modern flora and vegetation of their origin, above all, connected with the ancient Iranian, mainly Asia Minor or North Iranian flora penetrated here with Tertiary and being penetrated at the moment. From the more important temperate eastern slopes of the Lesser Caucasus in the Tertiary period, the study area was fenced off by the high perched Kongur-Alangez mountains and Zangezur.
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Retrospective analysis of reproduction processes of fixed capital of railway transport
Статья научная
Joint-stock company “Uzbek Railways” is the largest transport company in the country and in some segments of the transport market works in conditions of tough competition. With the development of market relations and economic growth, as well as competitive pressure from other participants in the transport market, reliable condition, efficient use and intensive reproduction of fixed assets are becoming increasingly important. In this regard, the research and development of effective methods of the reproductive process of the railway company. In this article, a retrospective analysis of the reproduction of the fixed capital of a railway company is carried out and suggestions are given for the intensification of this process.
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Review of digital tools to promote student engagement in online learning environment
Статья обзорная
The present article aims to discuss the significance of online student engagement and ways of promoting it in the era of digital learning. The Community of Inquiry framework presents the balanced structure of three dimensions, namely, the teacher, cognitive and social “presences” that are considered to be interrelated aspects of online courses to promote student engagement. The author also discusses the nature of synchronous and asynchronous module structures and their distinctive characteristics in online courses in line with several digital tools used during the pandemic lockdown in the 2020-2021 academic years that had major positive results in fostering online student engagement.
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Review of species of the Linaria mill. genus (Scrophulariaceae) in Azerbaijan
Статья обзорная
This article includes a taxonomic review of representatives of the Linaria Mill. genus growing in Azerbaijan. As a result of a critical review of the composition of the Linaria genus, it was found that 18 species and one subspecies of this genus grow in the study area, of which 3 species: L. hohenackeri, L. ordubadica, L. nachitschevanica are new to the flora of Azerbaijan. Nomenclatural and taxonomic changes are taken into account. A new key has been compiled to identify these species.
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Review on nearest level modulation methods based on MMC
Статья научная
In view of the relevant situation of offshore wind power research, development and construction at home and abroad, as well as the energy crisis facing the world, we have ushered in a new opportunity and outbreak period for the development of new energy. Therefore, higher requirements are placed on the power supply, and the key technology for the design of offshore wind power flexible DC transmission high-power converters is proposed. The Modular Multi-level Converter (MMC) topology can only use a lower switching frequency to obtain higher power Waveform quality. The output voltage waveform can effectively reduce the switching loss and filter capacity and improve the efficiency and economy of the converter. Among them, the method based on Level Modulation (NLM) is usually the preferred method. This paper introduces the topology and working principle of the modular multilevel converter (MMC) in detail and describes the improved modulation method for NLM in detail. The advantages, disadvantages and application occasions of different improved modulation techniques are summarized, which provides a reference for the engineering application of MMC.
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Revitalizing early stages of health and safety legislation as a challenge among major economies
Статья научная
A dynamically developing modern society is characterized by a powerful scientific and technological breakthrough. The application of knowledge can not only contribute to the evolution of society, but also threaten its safety. In the modern world due to the development of industrial technology danger grows faster than human resistance at work. The latter circumstance indicates the need to strengthen the prepara oftion citizens to safe behavior and their active civil security positions. Conditions of the new approach ensuthe red best work places based on the principle of Health and Safety towards regulation stages over the years among major economies. The main goal is to formulate safety regulations scientifically which study in solving the engineering problem, design-construction business, organizational or production process accidents. Challenges among major economies of 20 century were real implementations of theoretical approaches in health and safety in various methodologies.
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Role and place of Tash-Kumyr semiconductor materials plant in regional development
Статья научная
As for the construction of the Tash-Kumyr semiconductor materials plant, the best mining and metallurgical plant was associated with this plant. Semiconductor materials were used for the development of radio engineering and electrical production, and the construction of this plant in this area was one of the most important priorities of the city’s development. In the USSR, the production of semiconductor materials is not very developed. The Soviet government imported a large portion of semiconductor materials from the United States.
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Статья научная
During 2013-2017 years biotic and abiotic of environmental conditions affecting to the extensiveness of invasion by causative agents of carp and trout parasitosis in fish farms in the territory of Azerbaijan Republic were studied. In addition, we studied the seasonal and age dynamics of diseases of the farm fishes. The prevalence of fish parasites infection in hot season (May-July) in comparison with cold month (October) was recorded. Twenty species of parasites from various systematical groups were found: protozoans (4 species); monogenean worms (3 species); cestodes (4 species); trematodes (3 species); nematodes (2 species); acanthocephalans (2 species); crustaceans (2 species). All investigations were conducted by considering of various factors affecting on production of fish. 386 specimens of carp and 415 specimens of trout were examined by the method of full parasitological dissection. We analyzed the physical and chemical conditions of water from the fish pools and other artificial basins in fish farms. In conclusion of our investigation the list of most pathogenic species of cultivated parasites were composed: Metechinorhyncnus truttae, Acanthocephalus clavulae, Paradilepis scolecina, Proteocephalus torulosus, Rhabdochon agnedini .
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Role of micro-entrepreneurship in construction industry
Статья научная
The generally accepted view of the functions of a small business as a social institution that supports the competitive environment, employment and adaptive factors of the economy: a particular lifestyle, class. A manifestation of small business opportunities in the Soviet period of development was the cooperative sector of the economy, in many of the proposed modern enterprise formats. At the same time, small business is actively developing in the investment and construction sector in a highly qualified segment in the provision of accounting services, project management, design, estimates, and most importantly, coordination of design pushes forward effectiveness of the companies.
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Role of mitigating and aggravating circumstances in sentencing for crimes against minors
Статья научная
This article examines the role of mitigating and aggravating circumstances in sentencing for crimes against minors. It explores how these factors influence judicial decisions, ensuring proportionality and fairness in the punishment of offenders. The study highlights common aggravating circumstances, such as the use of violence and exploitation of trust, as well as mitigating factors, including the offender’s age, mental state, and voluntary compensation to the victim. A comparative analysis of sentencing practices in different jurisdictions reveals significant variations in the application of these factors. Recommendations are provided to enhance the consistency and effectiveness of individualized sentencing in line with international legal standards.
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Статья научная
The article analyzes deeper study of many foreign and local economist scientists, analyzing the dynamics and per capita changes in the mainstream agricultural products of the Republic of Uzbekistan for 2000-2016. Also, the Government of the Republic of Uzbekistan has provided scientifically substantiated proposals and recommendations based on the results of the dynamic change, taking into account the ongoing reforms in the development of the agricultural economy. Many scientific works will be a major factor in theoretical and practical scientific study of the problems of agricultural product market efficiency in the modernization of the economy, contributing to the agrarian-economic science. In spite of the fact that reforms in the Republic of Uzbekistan on the practical aspects of organizing, managing and increasing the effectiveness of the fruit and vegetable and grape sub-complex at the stage of economic liberalization, the above-mentioned researches did not adequately investigate the existing problems. In this paper have been used such research methodologies as: economic analysis, statistical grouping, comparative and systematic analysis, logical, monographic, etc.
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Статья научная
Collected and analyzed data on soil, ecological, climatic and relief conditions of the Mugan-Salyan cadastre region. The study of relief-climatic factors in the formation of soil and vegetation was carried out on the basis of both literary sources and our own research.
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