The performance of an inducer with the integration of an inlet cover bleed system known as a stability control device (SCD) is investigated using computational fluid dynamics. Inducers are the first stage of high suction performance pumps and are designed to operate under cavitating conditions. Improvements in design have allowed inducers to operate stably with low inlet head conditions, however, cavitation instabilities ultimately lead to pump failure. It has been shown that inducers that employ an SCD fully suppress cavitation instabilities.The performance of an inducer is explored at both on- and off-design flow coefficients, where the flow coefficient is a normalized flow rate through the inducer. Both the cavitating and non-cavitating performance of the inducer are analyzed. Improved stability is observed when the SCD is implemented, particularly at flow coefficients below the design value. The stabilizing effect of the SCD allows the inducer to operate stably at much lower flow coefficients, which allows for significant improvements in the pumps ability to operate with minimal inlet head. Cavitation instabilities, such as rotating cavitation, are also suppressed when the SCD is implemented.As part of this work, the design space created by the SCD is explored. Variations in the SCD geometry as well as the inlet blade angle of the inducer are explored. High suction performance pumps are required to operate at very low flow coefficients in order to have the best suction performance. Traditionally, only inducers with small inlet blade angles can maintain stable operation at very low flow coefficient. Because of the stabilizing effect of an SCD, inducers with larger inlet blade angles can now operate stably at the low flow rates require for high suction performance pumps. The influence of varying the inlet blade angle is explored in inducers that employ an SCD. This provides a better understanding of the flow physics in inducers that employ an SCD and help to define their design criteria. Stable operation at low flow coefficients is achieved with the larger inlet blade angles, confirming that inducers with larger inlet blade angles that employ an SCD can be used in high suction performance pumps. Modifications to the SCD geometry are considered to better optimize the design. Variations in the SCD geometry have almost no effect on the cavitation breakdown curve for each inducer, however, the stability of the pumps is greatly influenced by the SCD geometry. Some cavitation instabilities are observed in inducers that operate with an SCD. The physics that leads to the generation of these instabilities is unique to an inducer with an SCD. Modifications to the SCD geometry can allow inducers that employ an SCD to suppress traditional cavitation instabilities that occur without an SCD as well as the new instabilities that are observed when an SCD is implemented.

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Trata a presente tese de estudo acerca do instituto denominado recall, existente nos Estados Unidos da América do Norte, que constitui mecanismo que permite a destituição de autoridades públicas e a revogação de decisões judiciais, por meio de decisão popular. O ineditismo da tese decorre do aprofundamento que se fez sobre o tema, bem como da análise minuciosa sobre as condições de aplicação desse instituto no Brasil. Para compreensão integral do objeto em análise, inicialmente, buscou-se compreender o fenômeno da representação política, não só sob o aspecto jurídico-formal como também pelo aspecto histórico, político e social. As teorias acerca da representação política são abordadas dentro de uma perspectiva evolutiva, histórica, desde os seus traços primitivos nas sociedades antigas, passando pelas instruções e mandato imperativo do período medieval, até as concepções de Hobbes, Locke, Burke e Siéyès, não deixando de lado as posições mais modernas e os dilemas existentes sobre o tema. Busca-se também a essência desse mecanismo denominado recall. Para tanto, torna-se obrigatória a passagem pelas suas origens e pela sua configuração jurídica, que se encontra relacionada com o princípio federativo, os sistemas eleitorais, sua caracterização como direito político, instituto de democracia participativa e semidireta, bem como seu caráter sancionador e como forma de expressão da oposição política. Faz-se, além disso, uma análise comparativa do recall no direito contemporâneo. Inicialmente focando o instituto nos Estados Unidos da América do Norte, pelo âmbito de aplicação do instituto na Federação norte-americana, as hipóteses e procedimentos de cada Estado-membro (onde se permite o instituto) e os resultados gerais de sua aplicação. Analisar-se-á, outrossim, institutos semelhantes ao recall existentes em outros sistemas jurídicos. Ao final, será tratada a questão relacionada ao recall e o sistema jurídico brasileiro, apresentando-se a história da revogação do mandato político no país, o panorama jurídico pelo aspecto federativo e dos sistemas eleitorais, bem como as condições para viabilizar a aplicação do instituto no Brasil. Tudo isso, para se demonstrar que o recall deve ser um mecanismo democrático a ser utilizado por eleitores responsáveis contra eleitos irresponsáveis. / This dissertation focuses on the mechanism referred to as recall, which exists in the United States of America, and is a mechanism that provides for the removal of public officials and the repeal of judicial decisions by means of public opinion. The originality of this dissertation arises out of the further understanding of the subject, as well as of the thorough analysis of the conditions under which such mechanism could be applied in Brazil. In order to fully understand the analyzed object, it was first necessary to understand the phenomenon of political representation, not only from the formal-legal aspect, but also from the historical, political and social perspectives. The theories on political representation are approached from a historical-developing standpoint, from its primitive traces in ancient societies, to the medieval instruments and imperative mandate, to the ideas of Hobbes, Locke, Burke and Siéyès, in addition to the more modern schools of thought and existing dilemmas on the subject-matter. The dissertation also focuses on the essence of the recall mechanism. In order to do so, it was necessary to examine its origins and its legal configuration, which has to do with the federative principle, the electoral systems, its characterization as public law, participatory and semi-direct democracy, as well as its sanctioning ability and political opposition form of expression. Furthermore, the comparative analysis of recall in contemporary law is also carried out. The assessment is initially focused on the mechanism in the United States of America, as per its application in the North American Federation, the hypotheses and procedures of each Member-State (in which the mechanism is provided for) and the general results of its application. Moreover, similar mechanisms available in other legal systems are also analyzed. Finally, the issue of the recall mechanism and the Brazilian legal system is assessed, through the history of the repeal of political mandates in the country, its legal framework on the federative aspect and the electoral systems, as well as the conditions necessary in order to render the application of the recall mechanism in Brazil feasible. The objective is to demonstrate that the recall mechanism should be a democratic mechanism to be used by responsible voters against irresponsible elected officials.

Trata a presente tese de estudo acerca do instituto denominado recall, existente nos Estados Unidos da América do Norte, que constitui mecanismo que permite a destituição de autoridades públicas e a revogação de decisões judiciais, por meio de decisão popular. O ineditismo da tese decorre do aprofundamento que se fez sobre o tema, bem como da análise minuciosa sobre as condições de aplicação desse instituto no Brasil. Para compreensão integral do objeto em análise, inicialmente, buscou-se compreender o fenômeno da representação política, não só sob o aspecto jurídico-formal como também pelo aspecto histórico, político e social. As teorias acerca da representação política são abordadas dentro de uma perspectiva evolutiva, histórica, desde os seus traços primitivos nas sociedades antigas, passando pelas instruções e mandato imperativo do período medieval, até as concepções de Hobbes, Locke, Burke e Siéyès, não deixando de lado as posições mais modernas e os dilemas existentes sobre o tema. Busca-se também a essência desse mecanismo denominado recall. Para tanto, torna-se obrigatória a passagem pelas suas origens e pela sua configuração jurídica, que se encontra relacionada com o princípio federativo, os sistemas eleitorais, sua caracterização como direito político, instituto de democracia participativa e semidireta, bem como seu caráter sancionador e como forma de expressão da oposição política. Faz-se, além disso, uma análise comparativa do recall no direito contemporâneo. Inicialmente focando o instituto nos Estados Unidos da América do Norte, pelo âmbito de aplicação do instituto na Federação norte-americana, as hipóteses e procedimentos de cada Estado-membro (onde se permite o instituto) e os resultados gerais de sua aplicação. Analisar-se-á, outrossim, institutos semelhantes ao recall existentes em outros sistemas jurídicos. Ao final, será tratada a questão relacionada ao recall e o sistema jurídico brasileiro, apresentando-se a história da revogação do mandato político no país, o panorama jurídico pelo aspecto federativo e dos sistemas eleitorais, bem como as condições para viabilizar a aplicação do instituto no Brasil. Tudo isso, para se demonstrar que o recall deve ser um mecanismo democrático a ser utilizado por eleitores responsáveis contra eleitos irresponsáveis. / This dissertation focuses on the mechanism referred to as recall, which exists in the United States of America, and is a mechanism that provides for the removal of public officials and the repeal of judicial decisions by means of public opinion. The originality of this dissertation arises out of the further understanding of the subject, as well as of the thorough analysis of the conditions under which such mechanism could be applied in Brazil. In order to fully understand the analyzed object, it was first necessary to understand the phenomenon of political representation, not only from the formal-legal aspect, but also from the historical, political and social perspectives. The theories on political representation are approached from a historical-developing standpoint, from its primitive traces in ancient societies, to the medieval instruments and imperative mandate, to the ideas of Hobbes, Locke, Burke and Siéyès, in addition to the more modern schools of thought and existing dilemmas on the subject-matter. The dissertation also focuses on the essence of the recall mechanism. In order to do so, it was necessary to examine its origins and its legal configuration, which has to do with the federative principle, the electoral systems, its characterization as public law, participatory and semi-direct democracy, as well as its sanctioning ability and political opposition form of expression. Furthermore, the comparative analysis of recall in contemporary law is also carried out. The assessment is initially focused on the mechanism in the United States of America, as per its application in the North American Federation, the hypotheses and procedures of each Member-State (in which the mechanism is provided for) and the general results of its application. Moreover, similar mechanisms available in other legal systems are also analyzed. Finally, the issue of the recall mechanism and the Brazilian legal system is assessed, through the history of the repeal of political mandates in the country, its legal framework on the federative aspect and the electoral systems, as well as the conditions necessary in order to render the application of the recall mechanism in Brazil feasible. The objective is to demonstrate that the recall mechanism should be a democratic mechanism to be used by responsible voters against irresponsible elected officials.

The aim of this work is to design an architecture of the embedded device that will be used for controlling DAW software in recording studio. First of all, attention is given to a brief summary of the necessary knowledge which is needed to design such kind of device. Af- ter that follows short survey of the existing solutions and description of protocols which can be used for communication with the recording software. Then, subsequent part of the thesis builds upon these foundations and further elaborates the device architecture by me- ans of decomposing it into several modules. In fact, two hardware modules are designed and manufactured, when each of them is conceived on a separate PCB with its own microcon- troller. Then the control firmware has been implemented for each of the modules. At the end of the work an aluminium enclosure, which holds both modules, is designed. The result of this work is a functional prototype of the assembled controller which can be used for the purpose of controlling DAW software.

This project deals with portal-type CNC milling machine design and construction. CNC milling machine should be able to machining light metals and alloys. This document contains description of mechanical components selection, machine frame design and building, design and construction of USB motion control unit and also contains control software description and user manual.

The strand similarity and inclusion removal capability are two critical parameters to measure the performance of multi-strand tundish in clean steel production. In this work, the effect of two flow regulators, i.e., Flow Control Devices (FCD) and Electromagnetic Stirring (EMS) on eight-strand tundish performance have been investigated by establishing a water model and conducting numerical simulations of water model. The water model was focused on revealing the effect of stirring while the simulation was employed to investigate the effect of two FCDs, namely baffle wall and turbo-stopper. The analysis of strand similarity and inclusion removal were conducted by analyzing flow characteristics derived from Combined Model of Residence Time Distribution (RTD) curve and observing the flow movement in the tundish model. In addition, the tundish capability to remove inclusions was also studied by injecting inclusion particles using Discrete Phase Model (DPM) in ANSYS Fluent. Experiment results cause the Combined Model needs to be modified. This modification was employed when analyzing tundish configuration involving stirring. By using the modified Combined Model, the stirring can significantly increase the well-mix volume to almost 100% as it annihilates dead zone. The stirring also increases the similarity between strands and makes the RTD curve more similar to ideal mixing curve.  However, the problem of short-circuiting flow need to be solved and care should be taken into consideration regarding the selection of stirring direction as well as bath surface condition when implementing EMS in reality. The simulation results show that the addition of baffle wall and turbo-stopper are beneficial to improve mixing as well as to avoid the short-circuiting flow. Furthermore, compared to individual FCD, the combination of baffle wall and turbo-stopper results in the best performance to remove inclusions by providing surface-directed flow and generating a higher plug flow.

Работа выполнена на основании данных АО «НПО автоматики». Дипломный проект состоит из трех частей: Технологической, которая включает: описание конструкции детали; определение типа производства; разработку концепции механической обработки детали; выбор вида заготовки и метода её получения; конструирование заготовки и определение общих припусков на обработку; составление планов обработки каждой поверхности в соответствии с этапами обработки; разработку маршрута, включающего назначение базовых поверхностей, выбор станочного оборудования и технологической оснастки; моделирование эскизов на каждую операцию; определение операционных допусков и припусков на обрабатываемые поверхности; определение операционных размеров на обрабатываемые поверхности; выбор режимов обработки; определение норм времени на каждую операцию; оформление рабочей технологической документации. Конструкторской, которая включает: определение потребной силы закрепления (силовой расчёт); выбор и расчёт механизированного привода; точностной анализ приспособления; эскизное конструирование общего вида приспособления; проектирование контрольного приспособления; оформление рабочей конструкторской документации. Научно-исследовательской, которая включает экспериментальное исследование влияния режима резания на качество обрабатываемой поверхности из алюминиевого сплава АМг6 с последующим выводом уравнения регрессии. Графическая часть – 15 листов формата А1; Таблиц – 89; Рисунков – 44; Количество используемых источников – 19. / The work was performed on the basis of the data of JSC "NPO Automation". The graduation project consists of three parts: 1. Technological, which includes: description of the construction details; determining the type of production; development of the concept of machining parts; selection of the type of workpiece and the method of its receipt; design of the workpiece and the definition of total allowances for processing; drawing up plans for the treatment of each surface in accordance with the processing steps; development of the route, including the assignment of base surfaces, the choice of machine equipment and tooling; modeling sketches for each operation; Determination of operating tolerances and allowances for machined surfaces; determination of the operating dimensions of the treated surface; selection of processing modes; determination of time norms for each operation; registration of working technological documentation. Design, which includes: determination of the required strength of fastening (force calculation); selection and calculation of a mechanized drive; accuracy analysis of the device; conceptual design of the general form of the device; design of the control device; design of working design documentation. 3. Research, which includes an experimental study of the influence of the cutting mode on the quality of the processed surface of aluminum alloy AMg6 with the subsequent derivation of the regression equation. - Graphic part - 15 sheets of A1 format; - Tables - 89; Figures -40; The number of sources used - 18.

No description available.