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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Soporte arquitectónico a la sincronización imparcial de lectores y escritores en computadores paralelos

Vallejo Gutiérrez, Enrique 10 June 2010 (has links)
La evolución tecnológica en el diseño de microprocesadores ha conducido a sistemas paralelos con múltiples hilos de ejecución. Estos sistemas son más difíciles de programar y presentan overheads mayores que los sistemas uniprocesadores tradicionales, que pueden limitar su rendimiento y escalabilidad: sincronización, coherencia, consistencia y otros mecanismos requeridos para garantizar una ejecución correcta. La programación paralela tradicional se basa en primitivas de sincronización como barreras y locks de lectura/escritura, con alta tendencia a fallos de programación. La Memoria Transaccional (TM) oculta estos problemas de sincronización al programador; sin embargo, múltiples sistemas TM aún se basan en locks, y se beneficiarían de una implementación eficiente de los mismos.Esta tesis presenta nuevas técnicas hardware para acelerar la ejecución de estos programas paralelos. Proponemos un sistema TM híbrido basado en locks de lectura/escritura, que minimiza los overheads del software cuando la aceleración hardware está presente. Desarrollamos un mecanismo para garantizar fairness entre transacciones hardware y software. Introducimos un mecanismo distribuido de aceleración de locks de lectura/escritura, llamado Lock Control Unit. Finalmente, proponemos una organización de multiprocesadores basadas en Kilo-Instruction Processors que garantiza Consistencia Secuencial y permite especulación en secciones críticas. / Technological evolution in microprocessor design has led to parallel systems with multiple execution threads. These systems are more difficult to program and present higher performance overheads than the traditional uniprocessor systems, what may limit their performance and scalability: synchronization, coherence, consistency and other mechanisms required to guarantee a correct execution. Traditional parallel programming is based on synchronization primitives such as barriers, critical sections and reader/writer locks, highly prone to programming errors. Transactional Memory (TM) removes the synchronization problems from the programmer. However, many TM systems still rely on reader/writer locks, and would get benefited from an efficient implementation.This thesis presents new hardware techniques to accelerate the execution of such parallel programs. We propose a Hybrid TM system based on reader/writer locks, which minimizes the software overheads when acceleration hardware is present, still allowing for correct software-only execution. We propose a mechanism to guarantee fairness between hardware and software transactions is provided. We introduce a low-cost distributed mechanism named the Lock Control Unit to handle fine-grain reader-writer locks. Finally, we propose an organization of a mutiprocessor based on Kilo-Instruction Processors, which guarantees Sequential Consistency while allowing for speculation in critical sections.
52

Modeling and Characterization of Ammonia Injection and Catalytic Reduction in Kyrene Unit-7 HRSG

January 2011 (has links)
abstract: ABSTRACT The heat recovery steam generator (HRSG) is a key component of Combined Cycle Power Plants (CCPP). The exhaust (flue gas) from the CCPP gas turbine flows through the HRSG − this gas typically contains a high concentration of NO and cannot be discharged directly to the atmosphere because of environmental restrictions. In the HRSG, one method of reducing the flue gas NO concentration is to inject ammonia into the gas at a plane upstream of the Selective Catalytic Reduction (SCR) unit through an injection grid (AIG); the SCR is where the NO is reduced to N2 and H2O. The amount and spatial distribution of the injected ammonia are key considerations for NO reduction while using the minimum possible amount of ammonia. This work had three objectives. First, a flow network model of the Ammonia Flow Control Unit (AFCU) was to be developed to calculate the quantity of ammonia released into the flue gas from each AIG perforation. Second, CFD simulation of the flue gas flow was to be performed to obtain the velocity, temperature, and species concentration fields in the gas upstream and downstream of the SCR. Finally, performance characteristics of the ammonia injection system were to be evaluated. All three objectives were reached. The AFCU was modeled using JAVA - with a graphical user interface provided for the user. The commercial software Fluent was used for CFD simulation. To evaluate the efficacy of the ammonia injection system in reducing the flue gas NO concentration, the twelve butterfly valves in the AFCU ammonia delivery piping (risers) were throttled by various degrees in the model and the NO concentration distribution computed for each operational scenario. When the valves were kept fully open, it was found that it led to a more uniform reduction in NO concentration compared to throttling the valves such that the riser flows were equal. Additionally, the SCR catalyst was consumed somewhat more uniformly, and ammonia slip (ammonia not consumed in reaction) was found lower. The ammonia use could be decreased by 10 percent while maintaining the NO concentration limit in the flue gas exhausting into the atmosphere. / Dissertation/Thesis / M.S. Mechanical Engineering 2011
53

Unidade microcontroladora para gerenciamento eletrônico de um motor de combustão interna ciclo Otto. / Microcontroller electronic unit to manage an Otto cycle internal combustion engine.

Bruno Martin de Alcantara Dias 26 March 2015 (has links)
Nas últimas décadas, a indústria automobilística mundial vem investindo no desenvolvimento tecnológico dos motores, com o objetivo de alcançar melhor eficiência energética e atender às legislações que limitam a quantidade de resíduos tóxicos nos gases de exaustão e menor consumo de combustível. Isso resultou na implantação dos sistemas de gerenciamento eletrônico do motor, que possibilitam funcionalidades para se controlar diversas variáveis do motor, aumentando consideravelmente o rendimento do motor. Este trabalho tem como objetivos explorar a dinâmica de um motor de combustão interna ciclo Otto, os sinais elétricos associados, e os componentes de seu gerenciamento eletrônico. A partir dessas informações, o trabalho apresenta o processo de analise dos sinais elétricos e as estratégias de controle utilizadas em um sistema de gerenciamento real. Assim, são desenvolvidos o hardware e o firmware de uma unidade microcontroladora para gerenciamento eletrônico do motor. O hardware foi elaborado com uma concepção centralizada, ou seja, foi usado apenas um microcontrolador de 32-bit para gerenciar todas as funções. O firmware de controle foi desenvolvido de forma modular baseado em modelos de malha fechada. O modelo matemático do motor foi identificado utilizando técnicas de controle em um veículo real, e a avalidação do modelo foi obtida através de testes em um dinamômetro inercial. / In the last few decades, the world automotive industry has invested in the technological development of the engines, aiming to get better energetic efficiency and comply with legislations that limit the amount of toxic exhaustion gases. This resulted in electronic management systems for engines, which allowed flexibility to control several engine-related variables, considerably increasing the engine efficiency. This work aims to explore the Otto cycle combustion engine dynamics, its electronic signals, and the elements of its electronic management. Based on that information, this work presents the analysis process of the electronic signals, and the control strategies used in a real management system. Then, the hardware and firmware of a microcontroller unity are developed for the electronic management of the engine. The hardware was elaborated with a centralized concept, i.e., only one 32-bit microcontroller was used to control all functions. The control firmware was developed in a modular scheme, based on the closed loop models. The engine mathematical model was identified using control techniques in a real engine. The results were obtained by tests in an inertial dynamometer.
54

Translation of CAN Bus XML Messages to C Source Code

Andersson, Gustav January 2020 (has links)
The concept of translating source code into other target programming languages is extensively used in a wide area of applications. Danfoss Power Solutions AB, a company located in Älmhult, strives to streamline their way of software development for microcontrollers by implementing this idea. Their proprietary software tool PLUS+1 GUIDE is based on the CAN bus communication network, which allows electronic control units to share data represented in the XML format. Due to compatibility problems, the application in the electronic control units requires this data to be translated into the source code in the low-level C programming language. This thesis project proposes an approach for facilitating this task by implementing a source-to-source compiler that performs the translation with a reduced level of manual user involvement. A literature review was conducted in order to find the existing solutions relevant to our project task. An analysis of the provided XML input files was thereafter performed to clarify a software design suitable for the problem. By using a general XML parser, a solution was then constructed. The implementation resulted in a fully functional source-to-source compiler, producing the generated C code within a time range of 73–85 milliseconds for the input test files of typical size. The feedback received from the domain experts at Danfoss confirms the usability of the proposed solution.
55

Využitelnost OEE ve výrobním Automotive závodě / Usability of OEE in the Automotive manufacturing plant

Poledník, Tomáš January 2017 (has links)
This diploma thesis deals with the design and implementation of a comprehensive solution for the collection of production indicators in the commercial vehicle sector, called Automotive. The design is done by analyzing the state and identifying the bottlenecks of the OEE (Total Equipment Effectivenes). Further, the thesis describes the general theory of efficiency, availability and FPY (First Pass Yield). Realization and visualization of several production equipment variants for raw data collection from production lines in the manufacturing company IMI International CZ s.r.o. - a leading manufacturer of pneumatic components for the automotive and automation industry.
56

Řídící systém s HMI displejem / Industrial application of TS displays

Chytil, Lukáš January 2018 (has links)
This master thesis describes the design of control unit, which has the task to operate industrial facilities for disinfection of swimming pools or living rooms. The designed control unit is trying to regulate power and flow rate, which is controlled by electronic valve with a flowmetr. The whole design is aimed at minimizing operating costs (mainly consumed liquid oxygen). Interaction with the operator is ensured by the HMI display. There is also an effort to highlight the importance of HMI applications in the industry.
57

Úprava naftové elektrocentrály pro paralelní chod se sítí / Modification of a diesel generator for parallel operation with the grid

Černý, Martin January 2021 (has links)
This works applies the idea of adjustment an engine-generator, so it is possible to connect an engine-generator, or other type of a generator, to the electricity. Consequently, the machine can transform the power supply without an outage. This work concerns the complex approach, provides the descriptions of particular parts, sensors and active components of a motor-generator and includes the explanation of their function. Further research is focused on designing and drawing a plan with a choice of a control unit for the whole system. Finally, the work deals with the complex implementation and testing the machine in real operation.
58

Řídicí jednotka k automatickému přepínači / Automatic switch control unit

Zlý, Marián January 2009 (has links)
The main topic of this Master's Thesis is design and implementation of automatic range switch AC/DC Transfer Standart Fluke 792A. In the first part is introduce and description of character and the parameters AC/DC trasfer Standart Fluke 792A and design of the Automatic range switch for this equipment. In the next part is introduce design and description of realize automatic switch control unit it has comunication faculty witch PC over GPIB bus. In the finish part is show of the theoretic description for GPIB bus and her realization with helped microcontroller Atmega16.
59

Řízení pohybu modelu průmyslového robota / Movement control of an industrial robot model

Smrčka, Jiří January 2011 (has links)
The thesis aims to put in practice control unit of industrial robot ROB 2-6. The control unit is put in practice with the use of processor from the ARM STM32F100 family. Altogether with the control module it is supposed to be also realized HMI which will enable program loading and servicing of the control unit. The visualization model and algorithm of track planning is also realized within this work.
60

Smart Home - projekt inteligentního domu / Smart Home - project of intelligent house

Kretek, František January 2014 (has links)
This masters thesis deals with inteligent home electroinstallation which can distinctly decrease operating costs and make the house management much more easier. In this thesis will be described basic principles of data transfer, topology, instalation options and functions of particular units. Moreover there will be described systems and properities of solutions from the best known producers and suppliers of inteligent electroinstalations. The practical part describes the design house wiring system installation using Ego-n a solution using wireless installation Xcomfort.

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