Currently, there is a growing need for high-performance photocells with increased stability of pa... more Currently, there is a growing need for high-performance photocells with increased stability of parameters to external influences, such as thermal and radiation resistance. This work is devoted to the study of photocells available in the volume of an ordered micro-and nanostructure based on silicon doped with impurity nickel atoms. The study of the formation of micro-and nanoclusters of impurity atoms in silicon photocells that were subjected to additional high-temperature processing makes it possible to determine the degradation of nickel clusters, which strongly affect the electrical parameters of photocells. It is shown that impurity nickel atoms will increase the stability of the electrophysical parameters of photocells under the influence of both high temperature and radiation. The results obtained in the study showed that the introduction of nickel impurity atoms into the volume of silicon-based photocells leads to temperature and radiation resistance, and also increases efficiency.
The article discusses methods for monitoring solar radiation and wind characteristics and practic... more The article discusses methods for monitoring solar radiation and wind characteristics and practical principles of use. The efficiency of using solar and wind energy largely depends on how accurately the design took into account specific data on the arrival of solar radiation or wind speed at the site of the intended operation of installations. The instability of the primary energy supply makes it necessary to supply the installations with accumulators, the choice of capacity of which also affects the size of the energy receivers, and therefore the technical and economic indicators.
Universidade Federal de Juiz de Fora (UFJF), Mar 3, 2020
This master thesis presents a research about the utilization of Learning Styles as the primary cr... more This master thesis presents a research about the utilization of Learning Styles as the primary criteria for the construction of a recommender a system for Learning Objects. The primary needed characteristics for the creation of such system are identified, along with which steps are necessary for the usage of Learning Styles during the recommendation process. It is proposed a utility function for the recommendation process that utilizes Artificial Neural Networks. So as to carry these tests, synthetic data databases containing students based on the Felder & Silverman model and learning objects on the IEEE-LOM model were created. The results show possible inherent limitations on the method of Anitha and Deisy for the classification of learning objects to the Felder & Silverman model and also to the capacity of learning styles to be used as the main and only factor for the recommendation of learning material. From the conclusions it is seen that the addition of more elements beyond the learning styles that are also pertinent to the learning process and a bigger study about the implementation and training of the neural network could lead to the necessary path to suppress and even overcome the aforementioned limitations, which are the usage of the method proposed by Anitha and Deisy for converting IEEE-LOM learning objects to the FSLSM and the exclusive usage of learning styles as criteria of recommendation.Esta dissertação apresenta a pesquisa sobre a utilização de Estilos de Aprendizagem como critérios primários para a construção de um sistema de recomendação de Objetos de Aprendizagem. São identificadas as principais características necessárias para a criação de tal sistema, assim como quais passos são necessários para se utilizar Estilos de Aprendizagem durante um processo de recomendação. É proposta uma função utilidade para o processo de recomendação que faz uso de uma Rede Neural Artificial. Para a realização de testes, foram criadas bases de dados sintéticas de alunos baseadas no modelo de estilos de aprendizagem Felder & Silverman e de objetos de aprendizagem baseados no IEEE-LOM. Os resultados demonstram possíveis limitações inerentes do método de Anitha e Deisy para a classificação de objetos de aprendizagem para o modelo Felder & Silverman assim como da capacidade de utilização de estilos de aprendizagem como principais e únicos fatores para a recomendação de conteúdo educacional. Das conclusões tiradas, é visto que a adição de mais elementos pertinentes ao processo de educação e o maior estudo sobre a implementação e treino da rede neural podem ser o caminho necessário para suprimir e superar as limitações encontradas, que são o uso do método de Anitha e Deisy para converter objetos de aprendizagem do IEEE-LOM para o FSLSM e o uso exclusivo de estilos de aprendizagem como critério de recomendação.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio
Investigation of the features of the transition of self-oscillations of current from one type to ... more Investigation of the features of the transition of self-oscillations of current from one type to another in highly compensated silicon doped with impurity atoms of manganese, zinc and sulfur is of great interest from the point of view of studying both the mechanisms of self-sustained oscillations of the current and the physics of nonequilibrium processes. Based on the results obtained and the analysis performed, it has been established that the observed self-oscillations of the current in strongly compensated silicon are associated with nanoclusters of primus atoms. A model of a strongly compensated semiconductor is proposed to explain the mechanism of self-oscillations of the current in strongly compensated silicon, taking into account the multi-charge character of nano-clusters of atoms. It was found that the proposed model is in satisfactory agreement with the experimental results.
The paper studies the possibility of self-assembly of micro-particles of impurity atoms of nickel... more The paper studies the possibility of self-assembly of micro-particles of impurity atoms of nickel in silicon at certain thermodynamic conditions. It was shown that one could set the size, concentration and distribution of clusters of impurity atoms in the silicon lattice. Also, the effect of assembly of clusters was revealed.
The article discusses methods for monitoring solar radiation and wind characteristics and practic... more The article discusses methods for monitoring solar radiation and wind characteristics and practical principles of use. The efficiency of using solar and wind energy largely depends on how accurately the design took into account specific data on the arrival of solar radiation or wind speed at the site of the intended operation of installations. The instability of the primary energy supply makes it necessary to supply the installations with accumulators, the choice of capacity of which also affects the size of the energy receivers, and therefore the technical and economic indicators.
By finite-element modeling the process of forming a rectangular welded sheet package with gas und... more By finite-element modeling the process of forming a rectangular welded sheet package with gas under pressure was studied. It is found, that when a cylindrical dome is formed, the width of the package firstly decreases, and when it reaches the diameter of the shell, it begins to increase, i.e., the cylindrical shell deforms almost without thinning. Keywords superplastic molding, rectangular package, finite element modeling, cylindrical shell. [email protected]
IOP Conference Series: Materials Science and Engineering, 2020
This article considers a model of a solar photovoltaic station (PVS) integrated with a local elec... more This article considers a model of a solar photovoltaic station (PVS) integrated with a local electrical network on the example of a 20 kW PVS installed in the building of the Tashkent State Technical University named after Islom Karimov. The Basic SIMULINK model of an equivalent PVS was used for analysis and comparison of PVS parameters. It is shown that the parameters for the mathematical model match the experimental parameters obtained under natural operating conditions at remarkable points. This model of PVS will serve as an experimental and laboratory stand in the teaching of students of the University for the subject “Renewable energy sources” (RES).
There is great potential for generating solar energy using unused space on roofs and vacant lots ... more There is great potential for generating solar energy using unused space on roofs and vacant lots around buildings. Small amounts of energy generated by each individual household, industrial building, commercial building, or any other type of building can be used to partially meet the needs of the building's residents, and the surplus, if any, can be fed to the grid. To use the existing roof space of buildings, SPV systems on the roof of buildings can be installed to replace DG generators installed to provide the minimum load required to operate during load shedding. TSTU has a large unused roof area from both residential and office buildings. Therefore, it has a huge potential for generating solar energy by installing a grid-connected Solar system on the roof. We can reduce a large amount of bills by implementing a solar power plant. The government has also launched various solar energy incentive schemes, this article provides a brief overview of rooftop photovoltaic and small-s...
IOP Conference Series: Earth and Environmental Science, 2020
In this paper, the influence of overheating on the performance of photovoltaicmodules was evaluat... more In this paper, the influence of overheating on the performance of photovoltaicmodules was evaluated. The experimental observation was carried out on the basis of a 20 kW photovoltaic station with 60 photovoltaic modules. It was found that an increase in the number of solar cells with overheating in the photovoltaic module leads to an increase in output power losses. The temperature of the Feb is one of the main factors that determine the electrical parameters of the Feb and its efficiency in General. An increase in the SE temperature leads to a decrease in the band gap, which gives a slight increase in the photocurrent due to the expansion of the photo-response spectrum into the long-wave region. However, this increase in photocurrent does not compensate for the decrease in Uoc and the filling factor of the load characteristic FF due to an exponential increase in the saturation current with increasing temperature, which leads to a significant decrease in efficiency with increasing t...
The paper reports that under certain thermodynamic and doping conditions, the monoatomic and bina... more The paper reports that under certain thermodynamic and doping conditions, the monoatomic and binary clusters of impurity atoms in the silicon lattice are likely to assemble. The effect could help to shape nano-variband structures with controlled band gap.
The paper shows the possibility of self-organization of microparticles of impurity nickel atoms i... more The paper shows the possibility of self-organization of microparticles of impurity nickel atoms in silicon under certain thermodynamic conditions. It was found that the concentration of microparticles in the volume is distributed almost uniformly. It was found that upon additional annealing, self-ordering of microparticles of impurity atoms in the silicon bulk and the formation of Schottky micro-barriers occur. The study of the I – V characteristics of these samples showed that at the points where the microscopy of nickel atoms formed, it has a diode character. The obtained experimental data show the possibility of creating photocells (PV) based on compensated silicon by the impurity of nickel atoms. To study the fundamental electrophysical parameters of photocells, modern methods and instruments were used, such as an MIC-5 infrared analysis microscope, Oxford Instruments ZEISS EVOMA 10 REM analysis, XIA-200 atomic force microscope, and X'PertPowder diffractometer. Microand nano...
Austrian Journal of Technical and Natural Sciences, 2019
Large-scale application of solar power in all areas of the economy is mainly determined by the ef... more Large-scale application of solar power in all areas of the economy is mainly determined by the efficiency, reliability, and cost factors of solar cells. Currently, solar cells based on silicon have exhausted their peak capacity, the efficiency ratio of such elements is believed to hit 20%. Silicongermanium solid solutions are widely used in electronics and especially in nanoscale electronics technology. The unique properties of this material make it possible to create devices with parameters superior to those manufactured on the basis of A III B V compounds. It is known that solid solutions of Si 1-x Ge x is mainly produced by liquid-phase epitaxy or during cultivation. However, the above techniques barely allow to obtain solid solution on the crystal surface with desired thickness and composition. Neither allows it to engineer nanoscale structures on the basis of germanium in the silicon lattice.
Фундаментальные исследования (Fundamental research), 2021
В исследовании изучается влияние финансовых систем и качества политических институтов на эффектив... more В исследовании изучается влияние финансовых систем и качества политических институтов на эффективность независимости центрального банка в достижении более низкой инфляции. Деятельность центрального банка в рамках национальной экономики является одним из наиболее важных направлений реализации государственной экономической политики, поскольку от решений центрального банка и выбора инструментов монетарного регулирования зависит не только уровень инфляции и стоимость национальной денежной единицы, но и динамика общего экономического развития. Соответственно, вопросы характера и особенностей деятельности центрального банка являются достаточно актуальными в контексте выявления их роли в обеспечении ценовой и финансовой стабильности. В данной статье приводится исследование роли независимости центрального банка и ее степени в достижении низкого уровня инфляции и общей финансовой устойчивости национальной экономики. Проведен обзор зарубежной и отечественной литературы на выявление различных подходов к оценке эффективности независимого статуса центрального банка в проведении им монетарной политики. Общим для развитых и развивающихся стран является то, что более высокая степень независимости центрального банка более эффективна для снижения инфляции при высоком уровне развития банковского сектора и высоком уровне институционального качества.
Development and design of low power mobile and inexpensive solar stations are important for farme... more Development and design of low power mobile and inexpensive solar stations are important for farmers, individuals, geologists and trotters. The most important aspect is ensuring reliability of units in times of transportation, convenience and operational ease as well as minimum dimensions, low price. All the above will ensure large-scale implementation of solar stations in various applications and utilizations.
The possibility of building of clusters of impurity atoms of Ni in silicon and controlling their ... more The possibility of building of clusters of impurity atoms of Ni in silicon and controlling their parameters is currently investigated in the present research article. Our group develops a special technique for doping, the so-called " low-temperature doping " of semiconductors. This method of doping is based upon the diffusion process which is carried out in stages by gradually increasing temperature ranging from room temperature to the diffusion temperature. By using an atomic force microscope, one can obtain images as of physical objects (surfaces of solids), so much as of biological and chemical units (viruses and bacteria, atoms and molecules). Resolution of such microscopes sometimes reaches down the nanometer scale that allows us to observe individual atoms. AFM can do more than that. By using AFM, one can study the interaction of two objects, i.e. measure the force of friction, elasticity, adhesion, and move individual atoms across the surface, as well as depose and ...
Currently, there is a growing need for high-performance photocells with increased stability of pa... more Currently, there is a growing need for high-performance photocells with increased stability of parameters to external influences, such as thermal and radiation resistance. This work is devoted to the study of photocells available in the volume of an ordered micro-and nanostructure based on silicon doped with impurity nickel atoms. The study of the formation of micro-and nanoclusters of impurity atoms in silicon photocells that were subjected to additional high-temperature processing makes it possible to determine the degradation of nickel clusters, which strongly affect the electrical parameters of photocells. It is shown that impurity nickel atoms will increase the stability of the electrophysical parameters of photocells under the influence of both high temperature and radiation. The results obtained in the study showed that the introduction of nickel impurity atoms into the volume of silicon-based photocells leads to temperature and radiation resistance, and also increases efficiency.
The article discusses methods for monitoring solar radiation and wind characteristics and practic... more The article discusses methods for monitoring solar radiation and wind characteristics and practical principles of use. The efficiency of using solar and wind energy largely depends on how accurately the design took into account specific data on the arrival of solar radiation or wind speed at the site of the intended operation of installations. The instability of the primary energy supply makes it necessary to supply the installations with accumulators, the choice of capacity of which also affects the size of the energy receivers, and therefore the technical and economic indicators.
Universidade Federal de Juiz de Fora (UFJF), Mar 3, 2020
This master thesis presents a research about the utilization of Learning Styles as the primary cr... more This master thesis presents a research about the utilization of Learning Styles as the primary criteria for the construction of a recommender a system for Learning Objects. The primary needed characteristics for the creation of such system are identified, along with which steps are necessary for the usage of Learning Styles during the recommendation process. It is proposed a utility function for the recommendation process that utilizes Artificial Neural Networks. So as to carry these tests, synthetic data databases containing students based on the Felder & Silverman model and learning objects on the IEEE-LOM model were created. The results show possible inherent limitations on the method of Anitha and Deisy for the classification of learning objects to the Felder & Silverman model and also to the capacity of learning styles to be used as the main and only factor for the recommendation of learning material. From the conclusions it is seen that the addition of more elements beyond the learning styles that are also pertinent to the learning process and a bigger study about the implementation and training of the neural network could lead to the necessary path to suppress and even overcome the aforementioned limitations, which are the usage of the method proposed by Anitha and Deisy for converting IEEE-LOM learning objects to the FSLSM and the exclusive usage of learning styles as criteria of recommendation.Esta dissertação apresenta a pesquisa sobre a utilização de Estilos de Aprendizagem como critérios primários para a construção de um sistema de recomendação de Objetos de Aprendizagem. São identificadas as principais características necessárias para a criação de tal sistema, assim como quais passos são necessários para se utilizar Estilos de Aprendizagem durante um processo de recomendação. É proposta uma função utilidade para o processo de recomendação que faz uso de uma Rede Neural Artificial. Para a realização de testes, foram criadas bases de dados sintéticas de alunos baseadas no modelo de estilos de aprendizagem Felder & Silverman e de objetos de aprendizagem baseados no IEEE-LOM. Os resultados demonstram possíveis limitações inerentes do método de Anitha e Deisy para a classificação de objetos de aprendizagem para o modelo Felder & Silverman assim como da capacidade de utilização de estilos de aprendizagem como principais e únicos fatores para a recomendação de conteúdo educacional. Das conclusões tiradas, é visto que a adição de mais elementos pertinentes ao processo de educação e o maior estudo sobre a implementação e treino da rede neural podem ser o caminho necessário para suprimir e superar as limitações encontradas, que são o uso do método de Anitha e Deisy para converter objetos de aprendizagem do IEEE-LOM para o FSLSM e o uso exclusivo de estilos de aprendizagem como critério de recomendação.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio
Investigation of the features of the transition of self-oscillations of current from one type to ... more Investigation of the features of the transition of self-oscillations of current from one type to another in highly compensated silicon doped with impurity atoms of manganese, zinc and sulfur is of great interest from the point of view of studying both the mechanisms of self-sustained oscillations of the current and the physics of nonequilibrium processes. Based on the results obtained and the analysis performed, it has been established that the observed self-oscillations of the current in strongly compensated silicon are associated with nanoclusters of primus atoms. A model of a strongly compensated semiconductor is proposed to explain the mechanism of self-oscillations of the current in strongly compensated silicon, taking into account the multi-charge character of nano-clusters of atoms. It was found that the proposed model is in satisfactory agreement with the experimental results.
The paper studies the possibility of self-assembly of micro-particles of impurity atoms of nickel... more The paper studies the possibility of self-assembly of micro-particles of impurity atoms of nickel in silicon at certain thermodynamic conditions. It was shown that one could set the size, concentration and distribution of clusters of impurity atoms in the silicon lattice. Also, the effect of assembly of clusters was revealed.
The article discusses methods for monitoring solar radiation and wind characteristics and practic... more The article discusses methods for monitoring solar radiation and wind characteristics and practical principles of use. The efficiency of using solar and wind energy largely depends on how accurately the design took into account specific data on the arrival of solar radiation or wind speed at the site of the intended operation of installations. The instability of the primary energy supply makes it necessary to supply the installations with accumulators, the choice of capacity of which also affects the size of the energy receivers, and therefore the technical and economic indicators.
By finite-element modeling the process of forming a rectangular welded sheet package with gas und... more By finite-element modeling the process of forming a rectangular welded sheet package with gas under pressure was studied. It is found, that when a cylindrical dome is formed, the width of the package firstly decreases, and when it reaches the diameter of the shell, it begins to increase, i.e., the cylindrical shell deforms almost without thinning. Keywords superplastic molding, rectangular package, finite element modeling, cylindrical shell. [email protected]
IOP Conference Series: Materials Science and Engineering, 2020
This article considers a model of a solar photovoltaic station (PVS) integrated with a local elec... more This article considers a model of a solar photovoltaic station (PVS) integrated with a local electrical network on the example of a 20 kW PVS installed in the building of the Tashkent State Technical University named after Islom Karimov. The Basic SIMULINK model of an equivalent PVS was used for analysis and comparison of PVS parameters. It is shown that the parameters for the mathematical model match the experimental parameters obtained under natural operating conditions at remarkable points. This model of PVS will serve as an experimental and laboratory stand in the teaching of students of the University for the subject “Renewable energy sources” (RES).
There is great potential for generating solar energy using unused space on roofs and vacant lots ... more There is great potential for generating solar energy using unused space on roofs and vacant lots around buildings. Small amounts of energy generated by each individual household, industrial building, commercial building, or any other type of building can be used to partially meet the needs of the building's residents, and the surplus, if any, can be fed to the grid. To use the existing roof space of buildings, SPV systems on the roof of buildings can be installed to replace DG generators installed to provide the minimum load required to operate during load shedding. TSTU has a large unused roof area from both residential and office buildings. Therefore, it has a huge potential for generating solar energy by installing a grid-connected Solar system on the roof. We can reduce a large amount of bills by implementing a solar power plant. The government has also launched various solar energy incentive schemes, this article provides a brief overview of rooftop photovoltaic and small-s...
IOP Conference Series: Earth and Environmental Science, 2020
In this paper, the influence of overheating on the performance of photovoltaicmodules was evaluat... more In this paper, the influence of overheating on the performance of photovoltaicmodules was evaluated. The experimental observation was carried out on the basis of a 20 kW photovoltaic station with 60 photovoltaic modules. It was found that an increase in the number of solar cells with overheating in the photovoltaic module leads to an increase in output power losses. The temperature of the Feb is one of the main factors that determine the electrical parameters of the Feb and its efficiency in General. An increase in the SE temperature leads to a decrease in the band gap, which gives a slight increase in the photocurrent due to the expansion of the photo-response spectrum into the long-wave region. However, this increase in photocurrent does not compensate for the decrease in Uoc and the filling factor of the load characteristic FF due to an exponential increase in the saturation current with increasing temperature, which leads to a significant decrease in efficiency with increasing t...
The paper reports that under certain thermodynamic and doping conditions, the monoatomic and bina... more The paper reports that under certain thermodynamic and doping conditions, the monoatomic and binary clusters of impurity atoms in the silicon lattice are likely to assemble. The effect could help to shape nano-variband structures with controlled band gap.
The paper shows the possibility of self-organization of microparticles of impurity nickel atoms i... more The paper shows the possibility of self-organization of microparticles of impurity nickel atoms in silicon under certain thermodynamic conditions. It was found that the concentration of microparticles in the volume is distributed almost uniformly. It was found that upon additional annealing, self-ordering of microparticles of impurity atoms in the silicon bulk and the formation of Schottky micro-barriers occur. The study of the I – V characteristics of these samples showed that at the points where the microscopy of nickel atoms formed, it has a diode character. The obtained experimental data show the possibility of creating photocells (PV) based on compensated silicon by the impurity of nickel atoms. To study the fundamental electrophysical parameters of photocells, modern methods and instruments were used, such as an MIC-5 infrared analysis microscope, Oxford Instruments ZEISS EVOMA 10 REM analysis, XIA-200 atomic force microscope, and X'PertPowder diffractometer. Microand nano...
Austrian Journal of Technical and Natural Sciences, 2019
Large-scale application of solar power in all areas of the economy is mainly determined by the ef... more Large-scale application of solar power in all areas of the economy is mainly determined by the efficiency, reliability, and cost factors of solar cells. Currently, solar cells based on silicon have exhausted their peak capacity, the efficiency ratio of such elements is believed to hit 20%. Silicongermanium solid solutions are widely used in electronics and especially in nanoscale electronics technology. The unique properties of this material make it possible to create devices with parameters superior to those manufactured on the basis of A III B V compounds. It is known that solid solutions of Si 1-x Ge x is mainly produced by liquid-phase epitaxy or during cultivation. However, the above techniques barely allow to obtain solid solution on the crystal surface with desired thickness and composition. Neither allows it to engineer nanoscale structures on the basis of germanium in the silicon lattice.
Фундаментальные исследования (Fundamental research), 2021
В исследовании изучается влияние финансовых систем и качества политических институтов на эффектив... more В исследовании изучается влияние финансовых систем и качества политических институтов на эффективность независимости центрального банка в достижении более низкой инфляции. Деятельность центрального банка в рамках национальной экономики является одним из наиболее важных направлений реализации государственной экономической политики, поскольку от решений центрального банка и выбора инструментов монетарного регулирования зависит не только уровень инфляции и стоимость национальной денежной единицы, но и динамика общего экономического развития. Соответственно, вопросы характера и особенностей деятельности центрального банка являются достаточно актуальными в контексте выявления их роли в обеспечении ценовой и финансовой стабильности. В данной статье приводится исследование роли независимости центрального банка и ее степени в достижении низкого уровня инфляции и общей финансовой устойчивости национальной экономики. Проведен обзор зарубежной и отечественной литературы на выявление различных подходов к оценке эффективности независимого статуса центрального банка в проведении им монетарной политики. Общим для развитых и развивающихся стран является то, что более высокая степень независимости центрального банка более эффективна для снижения инфляции при высоком уровне развития банковского сектора и высоком уровне институционального качества.
Development and design of low power mobile and inexpensive solar stations are important for farme... more Development and design of low power mobile and inexpensive solar stations are important for farmers, individuals, geologists and trotters. The most important aspect is ensuring reliability of units in times of transportation, convenience and operational ease as well as minimum dimensions, low price. All the above will ensure large-scale implementation of solar stations in various applications and utilizations.
The possibility of building of clusters of impurity atoms of Ni in silicon and controlling their ... more The possibility of building of clusters of impurity atoms of Ni in silicon and controlling their parameters is currently investigated in the present research article. Our group develops a special technique for doping, the so-called " low-temperature doping " of semiconductors. This method of doping is based upon the diffusion process which is carried out in stages by gradually increasing temperature ranging from room temperature to the diffusion temperature. By using an atomic force microscope, one can obtain images as of physical objects (surfaces of solids), so much as of biological and chemical units (viruses and bacteria, atoms and molecules). Resolution of such microscopes sometimes reaches down the nanometer scale that allows us to observe individual atoms. AFM can do more than that. By using AFM, one can study the interaction of two objects, i.e. measure the force of friction, elasticity, adhesion, and move individual atoms across the surface, as well as depose and ...
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Papers by Elyor Saitov