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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.
21

Soluções de tomadas de decisões inteligentes para infraestruturas residenciais / Intelligent decision-making solutions for residential infrastructures

Rocha Filho, Geraldo Pereira 18 May 2018 (has links)
Nos últimos anos, um dos principais desafios globais está relacionado com a eficiência energética, sendo o desperdício de energia um dos fatores a ser destacado. Tal desperdício pode ser superado com o uso do Sistema de Automação Residencial (SAR). Vale frisar que os SARs são fortemente dependentes da sua infraestrutura interna, visto que esta é a base de uma casa inteligente. A Rede de Sensores e Atuadores sem Fio (RSASF) é uma solução promissora e de fácil implantação para ser utilizada como infraestrutura em um SAR. Entretanto, o uso das RSASFs como infraestrutura para monitorar e atuar (isto é, processo de tomada de decisão) no contexto de um SAR traz um novo problema. Tal problema remete não apenas a falta de um método para realizar a decisão dentro do próprio nó da RSASF, mas também a ausência em investigar um trade-off entre a precisão nas tomadas de decisões e o consumo de energia dos nós da rede. Além disso, a falta de uma infraestrutura distribuída, com baixo overhead e que reduza a latência do serviço são algumas das novas problemáticas para serem exploradas. Com isso, tem-se como desafio embarcar uma maior inteligência em dispositivos com recursos escassos, característica presente em uma RSASF. Para superar tais limitações, esta tese apresenta duas soluções de decisões inteligentes para uma infraestrutura residencial, nomeadas como ResiDI e ImPeRIum. O ResiDI é baseado em uma rede neural para atuar no processo de tomada de decisão dentro da RSASF, bem como em um mecanismo de correlação temporal para maximizar a eficiência energética da infraestrutura de comunicação. Já o ImPeRIum é baseado em um conjunto heterogêneo de dispositivos inteligentes para formar um ambiente computacional de fog, o qual gerencia as aplicações da residência por meio de uma rede neural. As soluções foram avaliadas extensivamente em diferentes cenários e comparadas com um trabalho da literatura. Os resultados reais e simulados, avaliados mediante uma análise estatística paramétrica e não-paramétrica, mostrou atingir o objetivo desta tese, sendo quatro deles notáveis: (i) aumento da precisão nas tomadas de decisões; (ii) redução no consumo de energia dos nós da rede; (iii) redução no tempo de resposta da atuação com baixa sobrecarrega; e (iv) eficiência na disseminação das informações. / In recent years, energy efficiency has become a major global challenge, and energy waste is a factor that needs to be highlighted. Such waste can be overcome with the use of Home Automation System (HAS). It should be stressed that the HASs are strongly dependent on its internal network, since this is the basis of a smart home. Wireless Sensor and Actuator Networks (WSANs) provide a modern and ubiquitous infrastructure for a smart home. However, the use of WSANs to monitor and act (i.e. decision-making process) as a control infrastructure within the context of HAS poses a new problem. Such problem refers not only to the lack of a method to execute the decision-making process within the WSAN, but also to the lack of investigating a trade-off between the decision-making accuracy and the extension of the WSAN nodes life-time. In addition, the lack of a distributed infrastructure, with low overhead in processing and that reduces service latency are some of the new problems to be addressed in the literature. With this, one has as a challenge to embark on greater intelligence in devices with scarce resources, a feature present in a WSAN. To overcome such limitations, this thesis presents two intelligent decision-making solutions for residential infrastructures, named ResiDI and ImPeRIum. ResiDI was developed based on a neural network to act in the decision-making process within the network, as well as a temporal correlation mechanism to maximize the energy consumption in the networks nodes. ImPeRIum was based on a heterogeneous set of smart objects to form a fog computational environment, which manages the applications of the residence through a neural network. The solutions were evaluated extensively in different scenarios and compared with an approach in the literature. The real and simulated results, evaluated through parametric and non-parametric tests, show that solutions make four key contributions: (i) increased decisionmaking; (ii) reduction in node energy consumption; (iii) reduction in action response time with low overload; and (iv) efficiency in the transmission of information.
22

Proposta de integração do sistema de automação de subestações retificadoras do sistema metrô-ferroviário brasileiro. / Proposal for the integrated automation of the brazilian subway system rectifier substations.

Carlos Alberto de Sousa 28 April 2010 (has links)
Esta dissertação apresenta uma proposta de integração sistêmica da automação das subestações retificadoras do sistema metrô-ferroviário brasileiro. Esta dissertação também apresenta os ganhos de confiabilidade que podem ser obtidos, caso a mesma seja implementada, e a priorização da eficiência de operação do sistema em questão. A motivação deste trabalho deve-se à necessidade de atender à perspectiva de aumento de demanda de energia elétrica nos processos de expansão e modernização deste sistema, amplamente usado pela população brasileira. A partir do estudo e análise do atual sistema de automação existente nas subestações do sistema metrô-ferroviário brasileiro, da arquitetura de hardware e software, foi possível investigar como a integração dos dados pertencentes aos sistemas de controle da subestação e do Centro de Controle Operacional CCO - pode permitir o aumento da confiabilidade e da flexibilidade de operação. Para quantificar estes ganhos de confiabilidade é apresentado o desenvolvimento do modelo de confiabilidade de Markov aplicado ao sistema de automação de subestações retificadoras. A metodologia utilizada procedeu ao levantamento e análise das ocorrências abertas nos anos de 2006, 2007 e 2008 nas subestações retificadoras do metrô de São Paulo, calculando o seu MTBF (Mean Time Between Failures). O estudo conclui que o ganho de confiabilidade é significativo no que se refere à melhoria do transporte público com a aplicação da integração da automação das subestações retificadoras. / This dissertation there presents a proposal for the integrated automation of the Brazilian subway system rectifier substations, supported on the gains of reliability which may be obtained in case it is implemented, and in the improvement of the efficiency of operation of the system open to question. The inquiry was supporting in the necessity of paying attention to the perspective of increase of demand of electric energy in the processes of expansion and modernization of this system, widely used by the Brazilian population. From the study and analysis of the current system of existent automation in the substations of the system Brazilian subway, of the architecture of hardware and software, was possible to investigate like the integration of the pertaining data to the systems of control of the substation and of the Centre of Operational Control CCO can allow the increase of the reliability and of the flexibility of operation. To quantify these profits of reliability there is presented the development of the model of reliability of Markov devoted to the system of automation of rectifying substations. The used methodology proceeded to the lifting and analysis of the incidents when they were opened in the years of 2006, 2007 and 2008 in the rectifier substations of the subway of Sao Paulo, calculating the MTBF (Mean Time Between Failures). The study ends that the profit of reliability is significant in what it refers to the improvement of public transport with the application of the integration of the automation of the rectifying substations.
23

國小圖書館自動化系統共建共享之研究:以全國閱讀推動與圖書管理系統網為例 / Collaborative building and sharing on the integrated library systems of elementary schools in Taoyuan

許嶸鴻, Hsu , Jung Hung Unknown Date (has links)
國民小學圖書館在缺乏人力、經費與技術支援的情況之下,圖書館自動化的發展明顯落後於其他類型的學校圖書館。為了改善此一現象,教育部自民國99學年度開始啟用「全國閱讀推動與圖書管理系統網」來協助中小學學校圖書館進行閱讀推動與圖書館自動化的實施。透過網路的連結,達成系統共建、資源共享的目標。 為了解「全國閱讀推動與圖書管理系統網」在國小圖書館實際使用的情況以及國小圖書館人員對該系統的接受情形,筆者以桃園縣公立小學圖書館為對象,藉由TAM科技接受模式修正版來評估使用者實際使用「全國閱讀推動與圖書管理系統網」的情形,並據此提出相關的建議。本研究以問卷調查法為主,訪談法為輔,以桃園縣188所公立小學圖書館的負責人為調查對象,透過問卷分析使用者對系統的認知情形與使用意願,並輔以訪談法蒐集使用者態度之後的原因來補充問卷資料的不足,以增加研究的正確性。 本研究調查發現「全國閱讀推動與圖書管理系統網」明顯的提升了國小圖書館實施自動化的比率,但由於使用者太多且集中在密集的時段使用系統,導致系統連線品質降低,影響系統的正常運作。教育訓練的不足與廠商服務的品質低落亦降低了使用者的滿意度。而「閱讀推動」的目標由於系統功能不符合學校實際推動閱讀的情境導致多數學校使用率偏低。研究者建議必須透過改善系統連線品質、加強教育訓練與提升服務品質來提升使用者的滿意度,達成系統建置的目標。 / Due to a lack of human resources, funding, and technical support for library automation, elementary school libraries have fallen much behind other types of school libraries in the development of library automation. To address this problem, Ministry of Education launched the “National Reading Promotion and Library Management System Website” in 2010. This system can assist elementary school libraries in promotion of reading and implementation of library automation. Its goal is to achieve co-construction of library systems and sharing of resources through the network. In order to understand the practical usage of the “National Reading Promotion and Library Management System Website” in elementary school libraries and acceptance of this website among librarians, this study investigated libraries of public elementary schools in Taoyuan County and applied the modified Technology Acceptance Model (TAM) to evaluate practical usage of this system. The methodology was based on survey and interview. The survey was administered to directors of 188 public elementary school libraries in Taoyuan County to understand users’ perceptions and usage intentions. The interview was conducted to explore factors behind user attitude, which could make up the insufficiency of survey data and increase the value of research findings. Results showed that the “National Reading Promotion and Library Management System Website” has significantly enhanced the percentage of library automation among elementary school libraries. However, the huge number of users of the system and their concentration of usage of the system in certain hours have resulted in a reduction of system connection quality, affecting the normal functioning of the system. Besides, insufficient education training and poor service quality of the system provider have also lowered user satisfaction with the system. With regard to “reading promotion”, the system’s functions are not conformed to the practical situations of reading promotion among elementary schools. As a result, the utility of these functions is low among most schools. Therefore, this study suggested that the authority concerned enhance user satisfaction and achieve the goals of the system by improving system connection quality, education training, and service quality first.
24

The integration between design and maintenance of office building automation : a decision support approach

Lin, Frank Ching-Shou January 2005 (has links)
This research explores the barriers and limitations of the interaction between building development processes in an attempt of an integrated decision support approach to improve building design for effective maintenance in the field of office building automation. Extensive coverage of literature and practice in office building industry over the last two decades indicates a wide diffusion and application of the information and communication technologies (ICT). While this has resulted in the adoption of advanced system integration in buildings, system redundancy and excessive expenditures are causing a major impact on the overall efficiency and has burdened building owners and occupiers with escalating maintenance costs. This phenomenon stimulates and warrants the re-examination of integrated building development, not just on system integration but also on the interdisciplinary development process integration particularly linking design and maintenance. Studies in this field revealed existing problems such as the inherent professional fragmentation, lack of historical information and service data, the first cost mentality of owners and developers, difficulties in forecasting future conditions and changes early in the design stage. With extensive use of qualitative information, this situation presents a great potential for the development of a decision support system exploring the communication and integration of design and maintenance phases, which has been one of the primary objectives of this research. In addition to literature studies, a questionnaire survey and a case study to identify industry concerns, feasible solutions, and practical procedure oriented approaches through knowledge extractions were carried out. A set of guidelines, a checklist for its implementation and prototype system for computerized decision support to design and maintenance of building automation systems were also produced. These strategic approaches to balance design and maintenance will help facilitate appropriate decision making in the early design stage for sustainable maintenance of buildings.
25

Développement d'une plateforme de co-simulation en vue de validation et d'évaluation de performances des systèmes de communication pour les installations de distribution électriques / Co-Simulation Platform for performance evaluation of communication networks 'application for smart grid communication architecture'

Haffar, Mohamad 21 September 2011 (has links)
Un système de distribution électrique est le cœur de tous types de sites industriels, aussi bien les sites producteurs d'énergie que les sites consommateurs. La sécurité de ce système doit être impérativement assurée par la mise en place des unités assurant plusieurs fonctionnalités de protection contre les dédauts électriques. Parmi ces fonctionalités il existe celles qui se basent sur des échanges d'information entre plusieurs unités de protection. Le standard IEC 61850 guarantit cet échange des informations via des signaux ‘temps réel' échangé via le réseau de communication. Vue l'aspet non deterministe de ces signaux, une étude poussée de leur fiabilité doit être effectuée. Pour ces raisons notre travail de thèse a pour objectif de mettre en place une méthodologie, basée sur une plateforme de Co-Simulation conçue pendant notre étude, qui permet la validation de la fiabilité de ces messages tout au long du cycle de vie d'un système de communication IEC 61850. / From 2004, a new worldwide standard of communication IEC61850 is introduced in the majority of substation automation system carrying out new innovation prospects to the world of substation. One of these feature is that it allows the exchange of security real time communication messages all over the communication network. These messages are used as control information for the Distributed Automation Application 'DAA'. Taking into consideration that DAA have a direct effect on ythe dependability of a smart grid architecture, the fiability of these real time IEC 61850 should be evaluated. For these reasons, our research delas with the development of a Co-Simulation platform that permits the evaluation and validation of an IEC 61850 communication network.
26

Soluções de tomadas de decisões inteligentes para infraestruturas residenciais / Intelligent decision-making solutions for residential infrastructures

Geraldo Pereira Rocha Filho 18 May 2018 (has links)
Nos últimos anos, um dos principais desafios globais está relacionado com a eficiência energética, sendo o desperdício de energia um dos fatores a ser destacado. Tal desperdício pode ser superado com o uso do Sistema de Automação Residencial (SAR). Vale frisar que os SARs são fortemente dependentes da sua infraestrutura interna, visto que esta é a base de uma casa inteligente. A Rede de Sensores e Atuadores sem Fio (RSASF) é uma solução promissora e de fácil implantação para ser utilizada como infraestrutura em um SAR. Entretanto, o uso das RSASFs como infraestrutura para monitorar e atuar (isto é, processo de tomada de decisão) no contexto de um SAR traz um novo problema. Tal problema remete não apenas a falta de um método para realizar a decisão dentro do próprio nó da RSASF, mas também a ausência em investigar um trade-off entre a precisão nas tomadas de decisões e o consumo de energia dos nós da rede. Além disso, a falta de uma infraestrutura distribuída, com baixo overhead e que reduza a latência do serviço são algumas das novas problemáticas para serem exploradas. Com isso, tem-se como desafio embarcar uma maior inteligência em dispositivos com recursos escassos, característica presente em uma RSASF. Para superar tais limitações, esta tese apresenta duas soluções de decisões inteligentes para uma infraestrutura residencial, nomeadas como ResiDI e ImPeRIum. O ResiDI é baseado em uma rede neural para atuar no processo de tomada de decisão dentro da RSASF, bem como em um mecanismo de correlação temporal para maximizar a eficiência energética da infraestrutura de comunicação. Já o ImPeRIum é baseado em um conjunto heterogêneo de dispositivos inteligentes para formar um ambiente computacional de fog, o qual gerencia as aplicações da residência por meio de uma rede neural. As soluções foram avaliadas extensivamente em diferentes cenários e comparadas com um trabalho da literatura. Os resultados reais e simulados, avaliados mediante uma análise estatística paramétrica e não-paramétrica, mostrou atingir o objetivo desta tese, sendo quatro deles notáveis: (i) aumento da precisão nas tomadas de decisões; (ii) redução no consumo de energia dos nós da rede; (iii) redução no tempo de resposta da atuação com baixa sobrecarrega; e (iv) eficiência na disseminação das informações. / In recent years, energy efficiency has become a major global challenge, and energy waste is a factor that needs to be highlighted. Such waste can be overcome with the use of Home Automation System (HAS). It should be stressed that the HASs are strongly dependent on its internal network, since this is the basis of a smart home. Wireless Sensor and Actuator Networks (WSANs) provide a modern and ubiquitous infrastructure for a smart home. However, the use of WSANs to monitor and act (i.e. decision-making process) as a control infrastructure within the context of HAS poses a new problem. Such problem refers not only to the lack of a method to execute the decision-making process within the WSAN, but also to the lack of investigating a trade-off between the decision-making accuracy and the extension of the WSAN nodes life-time. In addition, the lack of a distributed infrastructure, with low overhead in processing and that reduces service latency are some of the new problems to be addressed in the literature. With this, one has as a challenge to embark on greater intelligence in devices with scarce resources, a feature present in a WSAN. To overcome such limitations, this thesis presents two intelligent decision-making solutions for residential infrastructures, named ResiDI and ImPeRIum. ResiDI was developed based on a neural network to act in the decision-making process within the network, as well as a temporal correlation mechanism to maximize the energy consumption in the networks nodes. ImPeRIum was based on a heterogeneous set of smart objects to form a fog computational environment, which manages the applications of the residence through a neural network. The solutions were evaluated extensively in different scenarios and compared with an approach in the literature. The real and simulated results, evaluated through parametric and non-parametric tests, show that solutions make four key contributions: (i) increased decisionmaking; (ii) reduction in node energy consumption; (iii) reduction in action response time with low overload; and (iv) efficiency in the transmission of information.
27

Přístupové a zabezpečovací systémy v automatizaci budov / Access and Security System in Building Automation

Troják, Pavel January 2009 (has links)
This thesis deals with automation of buildings, provides the possibility of automation in today's intelligent buildings. The issue of building automation for security and access systems is solved in details. This thesis contains the basic rules of the systems and procedure in the implementation of access and security systems. The target of this thesis is the proposal of the access and security system for buildings. Part of the thesis is also creating a model, on which will be presented the access and security system. This model will be used by the company ELMONT GROUP as a basis for dealing with contracts.
28

Systém pro zpracování dat z regulátoru HAWK firmy Honeywell / HAWK controller data processing system

Dostál, Jiří January 2017 (has links)
This thesis deals with developing program components for collection of semantically labeled data from Honeywell's Hawk controller. The basic principles and capabilities of development using Niagara Framework, on which Hawk is based, are explained. Lastly, the specific components and external database application is described.
29

Monitoring, protection, and voltage control of parallel power transformers based on IEC 61850-9-2 process bus

Pieters, Willem Diederick January 2019 (has links)
Thesis (MEng (Electrical Engineering)--Cape Peninsula University of Technology, 2019 / The purpose of an electrical power system is to supply electrical energy to the customers. Power transformers are required to transform the system voltage from generation to transmission and distribution levels. Protection and control systems must ensure that power system high voltage equipment such as transformers operate and deliver save, reliable and secure electricity supply. The aim of the project research work is to develop and implement a strategy, methods and algorithms for monitoring, protection and voltage control of parallel power transformers based on IEC 61850-9-2 process bus standard. NamPower is a power utility in Namibia. The IEC 61850 protocol for electrical substation automation system is used for the protection and control of 5 power transformers operated in parallel in an existing substation system. The IEC 61850-9-2 process bus standard is however not used in regards of Sampled Values (SV). Protection and control devices are connected to a substation communication network, routers and switches using fibre optic linked Ethernet. Inductive Current Transformers (CTs) and Voltage Transformers (VTs) secondary circuits are hardwired to Intelligent Electronic Devices (IEDs) and fibre optic links are not used for this purpose at process level communication. The research focuses on the implementation of the IEC 61850 standard with Merging Units (MUs) and sampled values to improve the existing implemented protection and control system at NamPower. This includes substation communication networks and MUs used for transformer protection, voltage regulator control and cooling fan control. At the present the CTs located at the transformer bushings and switchgear and the VTs located at the switchgear are hardwired to the inputs on protection and control IEDs. The research focuses on issues with the copper wires for voltage and currents signals and how these issues can be eliminated by using the MUs and the SV protocol. The MUs which are considered in this Thesis is to improve the voltage regulator control and the control of the cooling fan motors. The voltage regulator control IED is situated at the tap change motor drive of the On-Load Tap Changer (OLTC). The IED of each transformer is required to regulate the voltage level of the secondary side bus bar it is connected to. All the regulating IEDs are required to communicate with each other and collectively to control the bus bar voltage depending on the switching configuration of the parallel transformers. The control circuit for controlling the cooling fan motors is hardwired. Temperature analogue signal input into a programmable automation controller IED can be used for controlling the transformer cooling fans. A strategy, methods and algorithms for transformer protection, voltage regulator control and cooling fan motor control of parallel power transformers need to be developed and implemented based on IEC 61850-9-2 process bus. Power utilities and distributors can benefit from interpretation of the IEC 61850-9-2 standard and implementing MUs and SV in substations. MUs can be included in the power transformer protection, automation and control systems. A cost reduction in high voltage equipment, substation installation and commissioning costs and better performance of protection and control system are anticipated.
30

Desarrollo de un sistema de automatización industrial aplicado a una máquina de moldeo por inyección para elaborar y enfriar piezas de plástico de polietileno de alta densidad / Development of an industrial automation system applied to an injection molding machine to process and cool high-density polyethylene plastic parts

Diaz Maldonado, Alexander Alberto, Rivera Ponce, Steven Roomel 09 March 2021 (has links)
La industria manufacturera en el Perú tiene una alta participación en la economía del país, conformando un 75% de la industria según la Sociedad Nacional de Industrias. Entre los principales rubros en apogeo se encuentra la producción de plásticos. Asimismo, una de las actividades económicas más demandantes en el 2016 fue la fabricación de productos hecho a base de polímeros. De esta manera, el aumento de pedidos relacionados con plásticos genera que las empresas dedicadas al rubro aumenten su producción mediante máquinas más especializadas, donde la infraestructura adicional que tienen estas máquinas facilita la producción de piezas de plástico; sin embargo, no todas tienen las mismas capacidades. En efecto, la empresa Firings E.I.R.L. cuenta con una máquina inyectora de plástico capaz de fabricar piezas hechas en polietileno; sin embargo, la infraestructura mecánica, eléctrica e hidráulica no se encuentra adaptada para soportar sus principales procesos, como la calibración de resistencias o el enfriamiento de las piezas fabricadas, causando retraso en la producción y exposición al operario a solventar estas carencias manualmente. De esta manera, el objetivo principal del proyecto consiste en desarrollar un sistema de automatización industrial para el proceso de fabricación y enfriamiento de piezas de plástico, mediante 3 etapas de desarrollo: un sistema de control en la unidad de inyección, un sistema de enfriamiento, y un cúmulo de interfaces visuales en tiempo real, con el propósito de reducir el tiempo perdido en la fabricación manual, y evitar accidentes eléctricos hacia el operario. / The manufacturing industry in Peru has a high participation in the country's economy, making up 75% of the industry according to the National Society of Industries. Plastics production is among the main booming industries. Also, one of the most demanding economic activities in 2016 was the manufacture of polymer-based products. In this way, the increase in orders related to plastics generates that the companies dedicated to the sector increase their production through more specialized machines, where the additional infrastructure that these machines have facilitates the production of plastic parts; however, not all have the same capabilities. Indeed, Firings E.I.R.L. It has a plastic injection machine capable of manufacturing parts made of polyethylene; However, the mechanical, electrical, and hydraulic infrastructure is not adapted to withstand certain factors, such as resistance calibration or cooling of the manufactured parts, causing delay in production and exposure to the operator to solve these deficiencies manually. In this way, the main objective of the project is to develop an industrial automation system for the manufacturing and cooling process of plastic parts, through 3 development stages: a control system in the injection unit, a cooling system, and a host of visual interfaces in real time, to reduce the time lost in manual manufacturing and avoid electrical accidents to the operator. / Tesis

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