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Бюллетень науки и практики @bulletennauki
Статьи журнала - Бюллетень науки и практики
Все статьи: 7472
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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Статья научная
Rosaceae spreading in mountain-xerophytic and steppe vegetation of Shahbuz district flora, is presented in the article. Information is given on the taxonomic composition, life forms, ecological groups, geographical area types and classes of woody species of the family. According to the researches conducted by us, when we characterized the woody species of the mountain-xerophyte and steppe zone of the Shahbuz district flora belonging to the Rosaceae family by genera, it was found that Rosa - 21 (37.5%), Crataegus - 7 (12.5%), Pyrus - 7 (12.5%), Prunus - 6 (10.71%), Sorbus - 5 (8.92%), Cotoneaster - 4 (7.14%), Rubus and Spiraea - 2 (3.57%), Malus and there is - 1 (1.78%) species of the Pyracantha genus. Shrub plants, especially woody species of the Rosaceae family, occupy an important place in the structure of Shahbuz district flora. They are part of the bush steppes, form independent groups and form unique formations.
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Rosmarinus officinalis L., properties, areas of application
Статья научная
Presents information about the botanical characteristics of rosemary, the regions and species of rosemary found in Azerbaijan, its chemical composition, fields of application, medicinal and therapeutic properties, as well as the preparation of its oil. The conducted research has revealed that there are two species of the genus Rosmarinus in nature: 1. Rosmarinus officinalis and Rosmarinus eriocalyx. In the flora of Nakhchivan Autonomous Republic, the species Rosmarinus officinalis is found, while Rosmarinus eriocalyx is encountered in the Mediterranean region. Based on literature data and our research, species belonging to this genus are used in medical, ecological, decorative, and cosmetic fields.
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Ru-содержащие катализаторы для жидкофазного синтеза Фишера-Тропша
Статья научная
Поиск новых стабильных и активных катализаторов синтеза Фишера-Тропша является одним из основных направлений производства жидких транспортных топлив из альтернативного сырья. Стабилизация активной фазы является одной из ключевых задач при разработке катализаторов гидрирования CO в жидкое моторное топливо. Эта задача может быть решена путем выбора оптимального носителя, а также метода синтеза. Настоящая работа посвящена разработке новых полимерных моно- и биметаллических Ru-содержащих нанокатализаторов для жидкофазного синтеза Фишера-Тропша. Показано, что использование 1% Ru-СПС и 10% Co - 1% Ru-СПС позволяет получать высокий выход бензиновых углеводородов диапазона C5-C9 (более 70%), обеспечивая высокую конверсию CO (до 23%). Выбранные системы на основе полимеров показали высокую стабильность в процессе синтеза Фишера-Тропша.
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Russian empire works on improving the Surkhan oasis irrigation system
Статья научная
The given article highlights the works of the Russian Empire done on improving the irrigation system of Surkhan oasis. There given factual information supported by archive materials and scientific literature.
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Russian native - Maga Rahmani: the first female writer of Afghanistan and her tadhkirats
Статья научная
This article discusses about Maga Rahmani who native Russian woman from Afghanistan was and who wrote very meaningful tadhkirats. Maga Rahmani was very first woman scholar who got involved in creative research. Her works contain much valuable information and facts concerned with the system of government in Mavarannahr, Iran, Afghanistan, and India. Also, some of her tadhkiras is an important source in studying the issues related to the Baburid period and the role of princesses in public policy and literature. The information provided by Maga Rahmani serves as an important source in covering the reforms carried out to improve the governance of the period, and in evaluating the poetry and art of the period under study. In her tadhkirat, Maga Rahmani focuses on the Baburids, mainly on the life and work of Akbarshah, Jahangir Mirza, Shah Jahan, and the queens of that period, Gulbadan Begim, Nurjahon Begim, and Zebunniso Begim. In turn, the tadhkirat of “Pardaneshinone suhanguy” is very valuable in studying the role of Baburi and Timurid princesses in public policy. This article research about life, works, activities of Maga Rahmani as well as the information can be obtained or felt about the political system, economical condition and cultural lifestyle of Afghanistan in XX century’s first half part.
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Статья научная
The effect of salt stress on several morpho-physiological characteristics of maize plants has been investigated in this study. Maize seedlings were treated with 0, 1, 2, and 3% NaCl for 5 days. It was shown that due to salinity, the growth traits (length of root and plant, fresh weight and dry weight of root and seedlings, leaf area, salt tolerance index, RWC, etc.) are significantly reduced. The relative water content in the leaves of the plant decreased gradually with increasing NaCl levels. High salt stress had a strong on root growth. Based on our results on the ultrastructure of the root obtained by electron microscopy, salinity slightly damaged the root anatomy.
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Salvia modesta Boiss. (Lamiaceae) - новый вид для флоры Азербайджана
Статья научная
При проведении флористических, геоботанических и этноботанических исследований в окрестностях сел Кюлюс, Биченек (плато Батабат), Агбулаг Шахбузского района Нахичеванской Автономной Республики Азербайджана впервые выявлен новый для флоры Азербайджана вид Salvia modesta Boiss. - шалфей скромный. Изучены биоэкологические и фитоценологические особенности вида, а также определены координаты местоположения.
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Scientific and practical foundations of teaching English in rural schools
Статья научная
The problems of foreign language teaching in rural areas are analyzed and summarized in the article. The author points out that the rural school is not only an institution of general education, but also a source of the well-being of the country, of stability, of the basic development of the society and of the spirituality of the people. In the article the peculiarities of the social-psychological and personnel training of a teacher of a foreign language and his use of modern developments and information technologies in the teaching are considered.
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Scientific approaches to the study of youth sociolect in linguistics
Статья научная
Modern linguistics has close connections with interlingual and intercultural communication. In this regard, one of the main components of scientific research is youth sociolect. It is the study of youth language that helps to predict the future development of modern spoken language. Currently, there are relatively few scientific linguistic works and studies devoted to the issue of the use of modern youth slang. This fact is explained by the entrenched view of the vocabulary of youth sociolect as something minor and not worthy of a scientific description. The relevance of this article is due to the need for a fuller identification and comprehensive study of youth sociolect as a special subsystem of the language, which is characterized by a certain range of speakers and its own vocabulary.
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Статья научная
The presented article provides extensive information on the use of some fodder plants common in the high-mountainous flora of the Nakhchivan. As an object of research, the highlands of Sharur, Shahbuz, Julfa, Ordubad, Babek and Kengerli districts were mainly studied. The conducted research allows to define important features characteristic for fodder plants, widespread in these territories. Forage plants form the basis of direct connection between crop and livestock production. The investigated various fodder plants, besides being valuable fodders, have taken a wide place in production due to a number of positive economic and biological properties. For the purpose of research, chemical composition of fodder plants and their fodder qualities were determined. Also, the chemical composition of 38 important forage species belonging to different species distributed in the flora of Nakhchivan in the course of numerous research and studies conducted by us, in percentage ratio, as well as other uses of these species are mentioned in the article mentioned. Thus, the study of fodder plants distributed in high mountainous areas is considered as an important scientific basis for identifying the directions of utilization of these plants.
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Scientific rationale for the development of low-intensity irrigation systems in Azerbaijan
Статья научная
The results of the study revealed that the mismatch intensity rain rate of water absorption into the soil formation of a surface relief and soil erosion, uneven and shallow soaking imperfection open irrigation system at a superficial irrigation, the need for different irrigation methods in the growing and not growing periods, low coefficient land utilization, high cost of irrigation and other features are, to a certain extent in conflict with the requirements of watering cultivated with techniques for / of crops in an area at the deep groundwater.
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Scope of negation: theory and double negatives
Статья научная
Research on the negative particles, studied in the context of pragmalinguistics and sociopragmatics serves to a deeper comprehending of the specifics of speech issues. In particular, due to the concept of negation, which is one of the integral units of speech, and the criteria for its application are various in different languages, it is important to study the specifics, similarities, and differences of negation in different languages on the basis of the comparative method. In this article scope of negation and its theoretical as well as double negatives will be discussed by contrasting different languages.
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