Central Asian Journal of STEM https://stem.ytit.uz/index.php/journal <p>The journal was registered at the Agency of Information and Mass Communications under the Administration of the President of the Republic of Uzbekistan. Certificate of Registration № 1133, 25/11/2020. The international journal "Central Asian Journal of STEM" is a semi-annual scientific publication published in electronic form in English, Uzbek and Russian. "Central Asian STEM Journal" is aimed at teachers, researchers and university specialists and is a professional scientific and analytical publication designed for a wide range of specialists in the field of science, technology, engineering and mathematics.</p> en-US akmal.rustamov@ytit.uz (Akmal Rustamov) o.mirzakhmedov@ytit.uz (Otabek Mirzakhmedov ) Tue, 31 May 2022 10:18:02 +0000 OJS http://blogs.law.harvard.edu/tech/rss 60 Г ОСНОВЫ ПРОЕКТИРОВАНИЯ ИНФОРМАЦИОННЫХ СИСТЕМ https://stem.ytit.uz/index.php/journal/article/view/37 <p><strong>Аннотация</strong>. В статье описаны этапы и методы разработки дизайна информационных систем. Подчеркнута важность создания и развития информационных систем для офисов и передовых предприятий многих стран. С появлением компьютерных технологий масштабная обработка информации и автоматизация основных производственных процессов и управления на всех уровнях стали важнейшей задачей обеспечения превосходства наиболее развитых стран и конкурентного преимущества коммерческих компаний.</p> Gulxan Dadenova Copyright (c) 2022 Central Asian Journal of STEM https://creativecommons.org/licenses/by-sa/4.0 https://stem.ytit.uz/index.php/journal/article/view/37 Mon, 30 May 2022 00:00:00 +0000 TRANSITION FROM FOSSIL FUELS TO RENEWABLE ENERGY IN UZBEKISTAN https://stem.ytit.uz/index.php/journal/article/view/48 <p><span class="fontstyle0">The viewpoint of Uzbekistan's energy system is examined in this thesis. The current statistics on the Uzbek energy system is complicated since some people simply include power generation, while others examine transportation, home resources, district heating, and the energy resources utilized to deliver these goods. Another impediment to studying the Uzbek energy system is the always-positive perspective of past studies. Neither the system's decision-makers nor scientists examine present situations with a critical eye. Indicators are inflated to state-by-state proportions, and events are explained solely from a positive perspective; yet, there is very little opportunity for positives when contrasted to negatives. Uzbekistan is a country that is energy self-sufficient and has a good overall energy balance. After the breakup of the Soviet Union, Uzbekistan was the only country to increase natural gas output by 35 percent. The temporal span of proved reserves is estimated to range<br>from 35 to 55 years in the most optimistic scenario. Other fossil fuels have a lower part of the market, with 7 and 8% for oil and coal, respectively. Oil output is expected to fall somewhat, while coal production is expected to improve slightly. Hydropower<br>generation has hit its peak and is unlikely to grow much. In Uzbekistan, nuclear energy is not used. In the next fifty years, it is expected to be Uzbekistan's primary source of energy. Fossil fuels will run out in less than fifty years due to significant<br>growth in production and net exports.</span> </p> Akmal Rustamov, Q.A. Sharipov Copyright (c) 2022 Central Asian Journal of STEM https://creativecommons.org/licenses/by-sa/4.0 https://stem.ytit.uz/index.php/journal/article/view/48 Mon, 30 May 2022 00:00:00 +0000 Second harmonic generation in branched waveguides https://stem.ytit.uz/index.php/journal/article/view/46 <p>We find the families of spatial walking solitons propagating in quadratic nonlinear media under conditions for type II second-harmonic generation in the presence of Poynting vector walk-off between the interacting beams. The analytical stability criterion for these three-parameter vector solitons is established. We study the shape and general properties of the solitons and their stability on propagation. It is found that the stationary solutions are stable at moderate positive phase mismatch. At phase matching and negative phase mismatch there are some unstable solutions near the cutoff.</p> Sulton Usanov, Mashrab Akramov, Sheroz Usanov Copyright (c) 2022 Central Asian Journal of STEM https://creativecommons.org/licenses/by-sa/4.0 https://stem.ytit.uz/index.php/journal/article/view/46 Mon, 30 May 2022 00:00:00 +0000 DETERMINATION OF THE DEPTH OF SOIL MOISTURE IN THE FOOTHILLS. https://stem.ytit.uz/index.php/journal/article/view/43 <p>The article is devoted to the results of field experiments carried out to improve water-saving technologies in horticulture and viticulture and to develop irrigation standards based on the management of the water-physical properties of the soil in the foothills. At the same time, in the drip irrigation system, the water consumption of droppers is set at the rate of 3-4 liters per hour, 30-40 liters per tree in the first year to moisten 50 cm of soil, in the second and third years up to 100-140 l to moisten 70 cm soil. Establishment of norms and timing of irrigation based on the biological needs of plants when irrigating orchards and vineyards in irrigated areas of Uzbekistan, increase the efficiency of irrigation water use by 15-18%, reduce labor and other costs. % reduction.</p> A.N. Jumanov Copyright (c) 2022 Central Asian Journal of STEM https://creativecommons.org/licenses/by-sa/4.0 https://stem.ytit.uz/index.php/journal/article/view/43 Mon, 30 May 2022 00:00:00 +0000 Техническая диагностика конструкций зданий. https://stem.ytit.uz/index.php/journal/article/view/38 <p>Technical diagnostics is one of the elements of the general theory of building reliability. Assessment of the state of structures at various stages of building operation establishes signs and causes of damage, makes it possible to identify defects in collapsing structures, to determine the extent and boundaries of damage in order to repair them in a timely manner and with high quality. Defects and damages can be classified according to reasons of occurrence, conditions of occurrence, external signs, degree of influence on performance characteristics. Diagnostics is one of the elements of the general theory of reliability and durability of buildings, its specific tasks are related to the early detection of defects and structural faults.</p> С.Т. Касымова Copyright (c) 2022 Central Asian Journal of STEM https://creativecommons.org/licenses/by-sa/4.0 https://stem.ytit.uz/index.php/journal/article/view/38 Mon, 30 May 2022 00:00:00 +0000 Advantages and disadvantages of distance learning. https://stem.ytit.uz/index.php/journal/article/view/18 <p><span class="VIiyi" lang="en"><span class="JLqJ4b ChMk0b" data-language-for-alternatives="en" data-language-to-translate-into="ru" data-phrase-index="0" data-number-of-phrases="1">This article describes the development of distance learning in universities, colleges, lyceums and schools in Uzbekistan.</span></span></p> Хуснутдин Насреддинов Copyright (c) 2022 Central Asian Journal of STEM https://creativecommons.org/licenses/by-sa/4.0 https://stem.ytit.uz/index.php/journal/article/view/18 Mon, 30 May 2022 00:00:00 +0000 Development of a mathematical model of the information system for data processing https://stem.ytit.uz/index.php/journal/article/view/47 <p>Modeling as a research method is a powerful tool of knowledge throughout the history of human development. The article describes the methodology for developing mathematical models of information systems, based on materials from various literary sources, author's developments on a systematic approach, mathematical modeling and programming. The mathematical model of the information system is described and all the characteristics of the IS are given.</p> Feruza Islamova Copyright (c) 2022 Central Asian Journal of STEM https://creativecommons.org/licenses/by-sa/4.0 https://stem.ytit.uz/index.php/journal/article/view/47 Mon, 30 May 2022 00:00:00 +0000 Synthetic fuel https://stem.ytit.uz/index.php/journal/article/view/44 <p><em>The article provides a variety of obtaining synthetic fuel from biological municipal waste. As well as increasing the role of various alcohols in internal combustion engines, dehydration methods for obtaining demitelethers from methanol.</em></p> Odil Odilov Copyright (c) 2022 Central Asian Journal of STEM https://creativecommons.org/licenses/by-sa/4.0 https://stem.ytit.uz/index.php/journal/article/view/44 Mon, 30 May 2022 00:00:00 +0000 Geographic data mapping of local runoff formation using GAT technologies. https://stem.ytit.uz/index.php/journal/article/view/41 <p>The article discusses the distribution of land resources by sectors of the economy in the development of sectors of the economy. Within each of them, land use is carried out by various enterprises, organizations, institutions. Within the boundaries of individual land holdings (land use), land serves as the main means of production (agriculture) or the basis of breadth, independent of its fertility, in particular, special attention is paid to the principles of rational use of land resources. In this regard, the effective use of available irrigated lands, their maintenance, restoration and improvement of soil fertility, their protection and intended use is one of the urgent tasks of our time. The advantage of the proposed method is that in experimental land management projects aimed at rational organization of land use and optimization of land and crop types, it is better to place pistachios and almonds on the slopes, and oilseeds and wheat on the lower slopes. in terms of efficiency.</p> A.N. Jumanov, M. Raimnazarova Copyright (c) 2022 Central Asian Journal of STEM https://creativecommons.org/licenses/by-sa/4.0 https://stem.ytit.uz/index.php/journal/article/view/41 Mon, 30 May 2022 00:00:00 +0000