1,443 research outputs found

    Grouping Method Of Image Fragments Of Adjacent Dislocation Etch Pits Of The Semiconductor Wafer

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    An increase in production volumes of gallium arsenide semiconductor devices determines the need for better control of dislocations of semiconductor wafer.The grouping method of image fragments of adjacent dislocation etch pits of the semiconductor wafer is proposed in the article. Adjacent fragments will be allocated in the pre-binarized image of wafer surface, which contains adjacent fragments of etch pits of dislocation loops after treatment by the described method. Improved methods for determining the loop line width determines the edge line width of etch pits of suspected dislocations, given the variability of their display in the binarized image. The current loop line width is compared to the reference line width of the dislocation loop.The grouping method of image fragments of adjacent dislocation etch pits of the semiconductor wafer defines recovery of loop lines branching, takes into account various options of line adjacency and determines the direction of further recovery of loop line of dislocation etch pits. A step by step description of the method is given

    Influence of Geoelectric Field on Chemical Reactions on Earth

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    The existing understanding of chemical thermodynamics presupposes that at the same temperature and other conditions being equal, the rate of a chemical reaction will always and everywhere on Earth be constant. We have found that geoelectric field generated by the Earth’s ionosphere, is capable of exerting a strong influence on the rate of chemical processes. Because of the revolution of the Earth around the Sun and varying intensity of the solar irradiance the geoelectric field is highly dynamic and causes the rate of some chemical reactions on the Earth to vary over wide ranges within a year.Існуюче уявлення про хімічну термодинаміку передбачає, що при однаковій температурі та інших рівних умовах швидкість хімічної реакції завжди і повсюди на Землі буде однаковою. Автором встановлено, що геоелектричне поле, що генерується іоносферою Землі, спроможне сильно впливати на швидкість хімічних процесів. Внаслідок обертання Землі навколо Сонця та інтенсивності сонячного випромінювання, що змінюється, геоелектричне поле дуже динамічне та спроможне викликати зміну швидкості деяких хімічних реакцій в широких межах впродовж року.Существующее представление о химической термодинамике предполагает, что при одинаковой температуре и прочих равных условиях скорость химической реакции всегда и везде на Земле является постоянной. Автором обнаружено, что геоэлектрическое поле, генерируемое ионосферой Земли, способно оказывать сильное влияние на скорость химических процессов. Вследствие вращения Земли вокруг Солнца и изменяющейся интенсивности солнечного излучения геоэлектрическое поле чрезвычайно динамично и способно вызывать изменение скорости некоторых химических реакций на Земле в больших пределах в течение года

    Precise grading and sorting of sunflower plant materials in industrial facilities

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    The purpose of our research is to increase the efficiency of the mechanical and technological process of sunflower seed mixture separation with vibro-pneumatic separators. This principle is based on the interaction of seed flow with the surface having vibration-type vibration load by substantiating their rational regime-technological parameters. A system of differential equations for the motion of sunflower seeds as granular gas under the action of a vibrating surface is considered, considering the elastic-damping interaction and the physical and mechanical properties of seeds. The solution of differential equations system is the basis of the physical and mathematical apparatus for the numerical system implemented in software package STAR-CCM +. To build physical and mathematical models, the sunflower seeds are assumed to have the form of ellipsoids with a certain density and effective diameter. As a result of numerical simulation of the process of moving sunflower seed material under the action of a vibrating sieve, the dependencies of the change in total concentration – θ and productivity – q on seed supply – Q, sieve angle – α, sieve oscillation frequency – ψ and sieve oscillation amplitude – A. numerical modelling of the process of moving sunflower seeds under the action of a vibrating surface, the dependencies of the change of filling factor – χ, distribution coefficient – δ and productivity – q on seed supply – Q, angles of inclination of vibrating surface – α and β, oscillation frequency – ψ, oscillation amplitude – A and a given air flow rate – V

    A hyper-parameterization method for comprehensive ocean models: Advection of the image point

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    Idealized and comprehensive ocean models at low resolutions cannot reproduce nominally-resolved flow structures similar to those presented in the high-resolution solution. Although there are various underlying physical reasons for this, from the dynamical system point of view all these reasons manifest themselves as a low-resolution trajectory avoiding the phase space occupied by the reference solution (the high-resolution solution projected onto the coarse grid). In order to solve this problem, a set of hyper-parameterization methods has recently been proposed and successfully tested on idealized ocean models. In this work, for the first time we apply one of hyper-parameterization methods (Advection of the image point) to a comprehensive, rather than idealized, general circulation model of the North Atlantic. The results show that the hyper-parameterization method significantly improves a non-eddy-resolving solution towards the reference eddy-resolving solution by reproducing both the large- and small-scale features of the Gulf Stream flow. The proposed method is much faster than even a single run of the coarse-grid ocean model, requires no modification of the model, and is easy to implement. Moreover, the method can take not only the reference solution as input data but also real measurements from different sources (drifters, weather stations, etc.), or combination of both. All this offers a great flexibility to ocean modellers working with mathematical models and/or measurements

    GROUPING METHOD OF IMAGE FRAGMENTS OF ADJACENT DISLOCATION ETCH PITS OF THE SEMICONDUCTOR WAFER

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    An increase in production volumes of gallium arsenide semiconductor devices determines the need for better control of dislocations of semiconductor wafer. The grouping method of image fragments of adjacent dislocation etch pits of the semiconductor wafer is proposed in the article. Adjacent fragments will be allocated in the pre-binarized image of wafer surface, which contains adjacent fragments of etch pits of dislocation loops after treatment by the described method. Improved methods for determining the loop line width determines the edge line width of etch pits of suspected dislocations, given the variability of their display in the binarized image. The current loop line width is compared to the reference line width of the dislocation loop. The grouping method of image fragments of adjacent dislocation etch pits of the semiconductor wafer defines recovery of loop lines branching, takes into account various options of line adjacency and determines the direction of further recovery of loop line of dislocation etch pits. A step by step description of the method is given

    Investigation of Photoelectric Converters with a Base Cadmium Telluride Layer with a Decrease in Its Thickness for Tandem and Two-sided Sensitive Instrument Structures

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    Photovoltaic cells with a base layer of cadmium telluride with a decrease in its thickness are studied. It is known that the widespread use of photovoltaic converters is constrained by their high price in the case of highly efficient instrument structures, or low efficiency. The creation of tandem and two-sided sensitive photoelectric converters will reduce their cost while increasing their efficiency. However, to create tandem and two-sided sensitive photoelectric converters, the necessary conditions are the use of transparent contacts and a decrease in the thickness of the base layer for efficient absorption of incident radiation by the converter, which is lower. In the research process, it was found that reducing the thickness of the base layer to 1 μm allows to increase the efficiency of the photoelectric transducer during irradiation from the back. An increase in the efficiency of the photoelectric converter occurs due to a decrease in the distance from the generation region of nonequilibrium charge carriers in the region of separation. If the thickness of the base layer is less than 1 μm, then regardless of which side of the irradiation is carried out, a decrease in the efficiency of the instrument structure is observed. Increase in the efficiency of photoconverters is associated with an increase in the negative influence of recombination processes on the back contact, a decrease in the number of charge carriers generated due to incomplete absorption of incident radiation, and a decrease in the volume of the built-in field of the separating barrier when it overlaps with the depletion region of the back contact. ITO/CdS/CdTe/Cu/ITO SCs with a base layer thickness of 1 μm demonstrates degradation stability. The highest value of efficiency in the case of illumination from the front side 8.1 % and with illumination from the back side 3.8 % received after a year of operation of the photovoltaic converter

    L’impacte del sistema de traspassos en els esports professionals: anàlisi organitzacional del nou sistema de traspassos de l’esport

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    Aquest article està dedicat als elements específics de les relacions laborals dels esportistes professionals. Els autors examinen el concepte i les característiques dels traspassos, així com les regles i les característiques d’aquests acords en diversos esports, com el futbol, l’hoquei, i en el marc de diverses federacions com la Federació Internacional d’Hoquei sobre Gel o la Federació d’Arts Marcials de Luxemburg. També s’analitzen els traspassos dels esportistes estudiants en l’entorn escolar i l’universitari. S’atorga gran importància a la influència de les normes de traspàs d’esportistes sobre les relacions laborals en els esports professionals. L’article té en compte els nous principis reguladors establerts després del cas Bosman i demostra els problemes legals essencials que sorgeixen arreu del fet que els clubs i els agents treuen molts més beneficis econòmics que els esportistes. Els autors suggereixen que cal reconsiderar el sistema de traspassos establert, tenint en compte l’anàlisi de les resolucions dels tribunals, i amb la finalitat d’ajudar la comunitat internacional a trobar nous principis i normes reguladores dels traspassos

    INVESTIGATION OF PHOTOELECTRIC CONVERTERS WITH A BASE CADMIUM TELLURIDE LAYER WITH A DECREASE IN ITS THICKNESS FOR TANDEM AND TWO-SIDED SENSITIVE INSTRUMENT STRUCTURES

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    Photovoltaic cells with a base layer of cadmium telluride with a decrease in its thickness are studied. It is known that the widespread use of photovoltaic converters is constrained by their high price in the case of highly efficient instrument structures, or low efficiency. The creation of tandem and two-sided sensitive photoelectric converters will reduce their cost while increasing their efficiency. However, to create tandem and two-sided sensitive photoelectric converters, the necessary conditions are the use of transparent contacts and a decrease in the thickness of the base layer for efficient absorption of incident radiation by the converter, which is lower. In the research process, it was found that reducing the thickness of the base layer to 1 μm allows to increase the efficiency of the photoelectric transducer during irradiation from the back. An increase in the efficiency of the photoelectric converter occurs due to a decrease in the distance from the generation region of nonequilibrium charge carriers in the region of separation. If the thickness of the base layer is less than 1 μm, then regardless of which side of the irradiation is carried out, a decrease in the efficiency of the instrument structure is observed. Increase in the efficiency of photoconverters is associated with an increase in the negative influence of recombination processes on the back contact, a decrease in the number of charge carriers generated due to incomplete absorption of incident radiation, and a decrease in the volume of the built-in field of the separating barrier when it overlaps with the depletion region of the back contact. ITO/CdS/CdTe/Cu/ITO SCs with a base layer thickness of 1 μm demonstrates degradation stability. The highest value of efficiency in the case of illumination from the front side 8.1 % and with illumination from the back side 3.8 % received after a year of operation of the photovoltaic converter

    Підвищення ефективності процесу потокового змішування сипких компонентів

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    Modern industrial and agricultural processing almost always implies mixing loose material on a variety of equipment. At present, there are known mixers of various designs, principles, and techniques to implement the technological process. One of the existing mixing techniques is a continuous flow method that has significant advantages – reducing energy intensity while improving the quality of the process of the mixture continuous preparation and distribution. However, the continuous-flow technique of mixing loose materials has been paid little attention to. This prevents the application of well-known analytical models of the process of moving loose components to substantiate the structural and technological parameters for the working bodies of a continuous flow mixer.The result of the analytical study of the continuous-flow mixing technique is the constructed system of differential equations of the movement of a bulk material’s components in the airflow under the influence of the working bodies’ surfaces of the designed mixer. The reported system of differential equations underlies the physical-mathematical apparatus for the numerical modeling of the specified process employing the software package StarCCM+ (USA).The result of the numerical modeling is the established dependences of the dynamics of change in the concentration of components in the mixture and the homogeneity of the mixture in the zones of a continuous flow mixer depending on the study factors (the frequency of rotations, the angle of attack of the blade mixer, the performance of feeding the first and second components).The optimal structural and technological parameters for a continuous flow mixer involved in the process of mixing a two-component feed mixture (stem and concentrated feed) have been determined, at which the uniformity of the resulting forage mixture is maximalСовременная промышленная и аграрная переработка почти всегда предполагает выполнение процесса смешивания сыпучего материала на различном оборудовании. На данный момент известны смесители различных конструкций, принципов и способов реализации технологического процесса. Среди существующих способов смешивания перспективным является потоковый способ, который имеет значительные преимущества – уменьшение энергоемкости при повышении качества процесса непрерывного приготовления и раздачи смеси. Однако исследованию потокового способа смешивания сыпучих материалов уделено мало внимания. Это не дает возможности использовать известные аналитические модели процесса перемещения сыпучих компонентов для обоснования конструктивно-технологических параметров рабочих органов смесителя потокового типа.В результате аналитических исследований потокового способа смешивания составлена система дифференциальных уравнений движения частиц компонентов сыпучего материала в воздушном потоке под действием поверхностей рабочих органов разработанного смесителя. Представленная система дифференциальных уравнений положена в основу физико-математического аппарата численного моделирования указанного процесса в пакете программного обеспечения StarCCM+ (США).В результате численного моделирования получены зависимости динамики изменения концентрации компонентов в смеси и однородности смеси от зон смесителя потокового типа в зависимости от факторов исследований (частота вращения, угла атаки лопастного смесителя, производительность подачи первого и второго компонентов).Для процесса смешивания двухкомпонентной кормовой смеси (стеблевой и концентрированный корма) определены оптимальные конструктивно-технологические параметры смесителя потокового типа, при которых однородность полученной кормосмеси является максимальнойСучасна промислова і аграрна переробка майже завжди передбачає виконання процесу змішування сипкого матеріалу на різноманітному обладнанні. На даний момент відомі змішувачі різноманітних конструкцій, принципів та способів реалізації технологічного процесу. Серед існуючих способів змішування є потоковий спосіб, який має значні переваги – зменшення енергоємності при підвищенні якості процесу безперервного приготування та роздавання суміші. Однак дослідженню потокового способу зміщування сипких матеріалів приділено мало уваги. Це не дає можливості використати відомі аналітичні моделі процесу переміщення сипких компонентів для обґрунтування конструктивно-технологічних параметрів робочих органів змішувача потокового типу.В результаті аналітичних досліджень потокового способу змішування складено систему диференційних рівнянь руху частинок компонентів сипкого матеріалу в повітряному потоці під дією поверхонь робочих органів розробленого змішувача. Представлена система диференційних рівняння покладена в основу фізико-математичного апарату чисельного моделювання зазначеного процесу в пакеті програмного забезпечення StarCCM+(США).В результаті чисельного моделювання отримані залежності динаміки зміни концентрації компонентів в суміші та однорідності суміші від зон змішувача потокового типу в залежності від факторів досліджень (частота обертів, кута атаки лопатевого змішувача, продуктивність подачі першого і другого компонентів).Для процесу змішування двокомпонентної кормової суміші (стебловий і концентрований корми) визначені оптимальні конструктивно-технологічні параметри змішувача потокового типу, при яких однорідність отриманої кормосуміші є максимально
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