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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.
31

Implementação da irradiação de corpo inteiro em radioterapia / Implementation of total body irradiation in radiotherapy

Habitzreuter, Ângela Beatriz 04 October 2010 (has links)
Ao implementar uma técnica de tratamento, as características do feixe nas condições de irradiação precisam ser bem conhecidas e estudadas. Cada um dos parâmetros utilizados para cálculo de dose deve ser medido e validado antes da utilização dos mesmos na rotina clínica. Isso se torna ainda mais necessário quando se tratam de técnicas especiais. Neste trabalho estão descritos todos os parâmetros e medidas necessárias para a implementação da irradiação de corpo inteiro numa instalação projetada para tratamentos convencionais, e que faz uso de geometrias não convencionais para gerar os tamanhos de campos alargados. Além disso, são apresentados os dados de comissionamento desta modalidade no Hospital das Clínicas de São Paulo utilizando a comparação de três tipos de detectores para medidas de dose de entrada durante tratamentos de irradiação de corpo inteiro. / Before implementing a treatment technique, the characteristics of the beam under irradiation conditions must be well acknowledged and studied. Each one of the parameters used to calculate the dose has to be measured and validated before its utilization in clinical practice. This is particularly necessary when dealing with special techniques. In this work, all necessary parameters and measurements are described for the total body irradiation implementation in facilities designed for conventional treatments that make use of unconventional geometries to generate desired enlarged field sizes. Furthermore, this work presents commissioning data of this modality at Hospital das Clínicas of São Paulo using comparison of three detectors types for measurements of entrance dose during total body irradiation treatment.
32

Modelo conceitual para comissionamento de sistemas prediais. / Conceptual model for building systems commissioning.

Christianne dos Santos Figueiredo Ishida 19 November 2015 (has links)
Atualmente, os edifícios, em função dos avanços tecnológicos dos sistemas prediais, necessitam de maior planejamento, detalhamento de projetos, controles de execução e treinamento dos profissionais de operação e manutenção para atender os requisitos de projeto do proprietário, que têm como premissa os conceitos de sustentabilidade, qualidade e desempenho. A presença dos sofisticados sistemas de controle contribui para facilitar o gerenciamento de insumos como água e energia, porém pequenas falhas podem levar a grandes falhas de desempenho. As falhas na concepção dos edifícios têm início com a má interpretação, por parte da equipe técnica, dos requisitos dos proprietários. Assim, é necessário que na concepção do edifício sejam verificados todos os requisitos solicitados pelos proprietários para o edifício durante o seu ciclo de vida. A falha da comunicação percorre toda a cadeia produtiva do edifício gerando falhas de planejamento, projeto, execução e manutenção. O comissionamento é um processo para atender aos requisitos de projeto do proprietário, documentar as fases do ciclo de vida dos edifícios, capacitar os profissionais de operação e manutenção, com o objetivo de evitar as falhas, diminuir desperdícios e retrabalhos, melhorar a qualidade, o desempenho e a sustentabilidade dos edifícios. O comissionamento é mais difundido em sistemas prediais de ar condicionado e de iluminação tendo como meta a alta eficiência energética e a economia de água, sendo pouco utilizado no Brasil. Neste contexto, o objetivo desta pesquisa é propor um modelo conceitual de comissionamento para sistemas prediais. A metodologia adotada para o desenvolvimento do modelo, utiliza a pesquisa bibliográfica como procedimento técnico. Para elucidar em que fase o comissionamento é aplicado, este foi relacionado com os outros conceitos utilizados no ciclo de vida do edifício como a coordenação de projeto, o gerenciamento de execução, o gerenciamento de facilidades, a qualidade, o desempenho, a sustentabilidade. Para o desenvolvimento do modelo conceitual é apresentado um fluxo das fases do ciclo de vida e respectivas etapas do comissionamento e outro fluxo com a relação de documentos gerados em cada fase. O resultado, ou seja, o modelo conceitual dá as diretrizes para o desenvolvimento de um comissionamento por meio da descrição das atividades, das competências e dos produtos gerados em cada etapa do comissionamento, conforme as fases do ciclo do edifício. Este trabalho contribui para difundir o comissionamento e embasar a sua aplicação em edifícios. / The buildings of high technology, arising from technological advances in building systems, require more planning, project details, playback controls and training of operating professionals and maintenance to meet the owner\'s project requirements, which is premised on the concept of sustainability, quality and performance. The presence of sophisticated control systems helps to facilitate the management of inputs such as water and energy, however small faults can lead to major performance failures. The flaws in the design of the buildings begin to misinterpretation, by the technical staff, the requirements of the owners. Thus, it is necessary that the design of the building are checked all requirements requested by the building owners to during its life cycle. The failure of the communication runs through the entire production chain of the building generating design flaws, design, execution and maintenance. Commissioning is a process to meet the owner\'s project requirements, document the stages of the life cycle of buildings, train operating professionals and maintenance, in order to avoid failures, reduce waste and rework, improve quality, performance and sustainability of buildings. The commissioning is more widespread in building air conditioning and lighting systems with the goal of high energy efficiency and water savings, being little used in Brazil. In this context, the objective of this research is to propose a conceptual model of commissioning for building systems. The methodology used to develop the model, uses literature as a technical procedure. To elucidate what stage the commissioning is applied, this was related to the other concepts used in the building\'s life cycle, such as: project coordination, execution management, management of facilities, quality, performance, sustainability. To develop the conceptual model presented is a flow of phases of the life cycle and respective process steps and another stream with the list of documents generated at each stage. The result, i.e. the conceptual model gives guidelines for the development of a commissioning through the description of activities, skills and products generated at each stage of the commissioning, according to the phases of building cycle. This work contributes to spread the commissioning and to support its application in buildings.
33

Implementação da irradiação de corpo inteiro em radioterapia / Implementation of total body irradiation in radiotherapy

Ângela Beatriz Habitzreuter 04 October 2010 (has links)
Ao implementar uma técnica de tratamento, as características do feixe nas condições de irradiação precisam ser bem conhecidas e estudadas. Cada um dos parâmetros utilizados para cálculo de dose deve ser medido e validado antes da utilização dos mesmos na rotina clínica. Isso se torna ainda mais necessário quando se tratam de técnicas especiais. Neste trabalho estão descritos todos os parâmetros e medidas necessárias para a implementação da irradiação de corpo inteiro numa instalação projetada para tratamentos convencionais, e que faz uso de geometrias não convencionais para gerar os tamanhos de campos alargados. Além disso, são apresentados os dados de comissionamento desta modalidade no Hospital das Clínicas de São Paulo utilizando a comparação de três tipos de detectores para medidas de dose de entrada durante tratamentos de irradiação de corpo inteiro. / Before implementing a treatment technique, the characteristics of the beam under irradiation conditions must be well acknowledged and studied. Each one of the parameters used to calculate the dose has to be measured and validated before its utilization in clinical practice. This is particularly necessary when dealing with special techniques. In this work, all necessary parameters and measurements are described for the total body irradiation implementation in facilities designed for conventional treatments that make use of unconventional geometries to generate desired enlarged field sizes. Furthermore, this work presents commissioning data of this modality at Hospital das Clínicas of São Paulo using comparison of three detectors types for measurements of entrance dose during total body irradiation treatment.
34

Qualificação de sistemas fotovoltaicos conectados à rede / Qualification of Grid-Connected Photovoltaic Systems

Marcelo Pinho Almeida 30 May 2012 (has links)
Este trabalho propõe um procedimento para qualificar sistemas fotovoltaicos conectados à rede, o qual possui dois focos principais: o comissionamento e a caracterização da produção de energia. Também resume alguns aspectos normativos relacionados aos sistemas fotovoltaicos, apresenta os principais parâmetros de desempenho utilizados para caracterizar um sistema fotovoltaico, propõe uma metodologia para calcular a energia injetada na rede, a qual incorpora modelos matemáticos e procedimentos de medição, tanto novos quanto convencionais, e aplica essa metodologia em um estudo de caso de um sistema fotovoltaico real. / This work proposes a procedure for qualifying grid-connected photovoltaic systems, which has two main focuses: the commissioning and the characterization of energy production. The work also summarizes some regulatory aspects related to photovoltaic systems, presents the main parameters used to characterize the performance of a photovoltaic system, proposes a methodology to calculate the energy injected into the grid, which incorporates both new and conventional mathematical models and measurement procedures, and applies this methodology to a case of study of a real photovoltaic system.
35

A component-based virtual engineering approach to PLC code generation for automation systems

Ahmad, Bilal January 2014 (has links)
In recent years, the automotive industry has been significantly affected by a number of challenges driven by globalisation, economic fluctuations, environmental awareness and rapid technological developments. As a consequence, product lifecycles are shortening and customer demands are becoming more diverse. To survive in such a business environment, manufacturers are striving to find a costeffective solution for fast and efficient development and reconfiguration of manufacturing systems to satisfy the needs of changing markets without losses in production. Production systems within automotive industry are vastly automated and heavily rely on PLC-based control systems. It has been established that one of the major obstacles in realising reconfigurable manufacturing systems is the fragmented engineering approach to implement control systems. Control engineering starts at a very late stage in the overall system engineering process and remains highly isolated from the mechanical design and build of the system. During this stage, control code is typically written manually in vendor-specific tools in a combination of IEC 61131-3 languages. Writing control code is a complex, time consuming and error-prone process.
36

An approach to open virtual commissioning for component-based automation

Kong, Xiangjun January 2013 (has links)
Increasing market demands for highly customised products with shorter time-to-market and at lower prices are forcing manufacturing systems to be built and operated in a more efficient ways. In order to overcome some of the limitations in traditional methods of automation system engineering, this thesis focuses on the creation of a new approach to Virtual Commissioning (VC). In current VC approaches, virtual models are driven by pre-programmed PLC control software. These approaches are still time-consuming and heavily control expertise-reliant as the required programming and debugging activities are mainly performed by control engineers. Another current limitation is that virtual models validated during VC are difficult to reuse due to a lack of tool-independent data models. Therefore, in order to maximise the potential of VC, there is a need for new VC approaches and tools to address these limitations. The main contributions of this research are: (1) to develop a new approach and the related engineering tool functionality for directly deploying PLC control software based on component-based VC models and reusable components; and (2) to build tool-independent common data models for describing component-based virtual automation systems in order to enable data reusability.
37

Commissioning and validation of small subfields in Step-and-shoot IMRT

Andræ, Nils January 2008 (has links)
<p>One of the most used irradiation techniques in modern radiation therapy is step-and-shoot IMRT. The accuracy of this technique when delivering complex dose distributions strongly depends on the size of the subfields. The aims of this study is to determine the minimum size of subfields that can be used efficiently in Step-and-Shoot IMRT, to investigate the validation process for beam delivery and treatment planning dose calculations, and to find recommendations for practical clinical implementations.</p><p>Two different detectors, a CC04 ion chamber and a SFD stereotactic diode, have been used for measuring head scatter factors in air (Sc), total output factors (Scp) and dose profiles in water for a wide range of field sizes. The measurements were compared to calculations done with a pre-release version of the Nucletron MasterPlanTM v 3.1 treatment planning system that employs a novel, high resolution fluence modelling for both its pencil beam and collapsed cone dose calculation algorithms. Collimator settings were explicitly checked using FWHM film measurements with a build-up sheet of tungsten placed close to the treatment head to reduce the influence from lateral electron transport and geometrical penumbra. An analysis of the influence and sensitivity of Scp for small fields with respect to the linear accelerator source size and shape was also made.</p><p>The measurements with the ionization chamber and the stereotactic diode showed good agreements with each other and with the treatment planning system calculations for field sizes larger than 2×2 cm2. For small field sizes, measurements with different detectors yielded different results. Calculations showed agreements with measurements with the smallest detector, provided careful field size calibration and commissioning of calculation parameters. Uncertainties in collimator settings and source characteristics were shown to yield large uncertainties in Scp for fields smaller than 2×2 cm2.</p><p>The treatment planning system was found to properly handle small subfields but results were very sensitive to uncertainties in source size, as well as calibration and reproducibility of the collimator settings. Therefore if subfields smaller than 2×2 cm2 are to be used in IMRT extra care should be taken to determine the source characteristics and to calibrate the collimators. The volume of the detectors used for validation of such small fields and the loss of charged particle equilibrium conditions also have to be taken into consideration.</p>
38

About the Use of Radiant Ceiling Simulation Models as Commissioning Tools

Fonseca Diaz, Nestor Julio 16 December 2009 (has links)
This study focuses on the experimental and theoretical analyses of radiant ceiling performance and on the use of their simulation models as commissioning tools. A steady state model of such system appears to be an appropriate tool for preliminary calculation, design and diagnosis in commissioning processes. Therefore, the main objective is to support a Functional Performance Test of the system in order to verify the radiant ceiling performance in cooling and/or heating modes. A series of experimental results obtained for seven types of cooling ceilings are used in order to validate this model. A dynamic model is also proposed to interpret the interactions of the radiant ceiling system with its environment (walls, facade, internal loads and ventilation system). This dynamic model is used to support a global commissioning procedure, to verify the radiant ceiling behavior and to evaluate the comfort conditions of the occupants. In this modeling the resultant temperature is calculated as a comfort indicator, as it depends strongly on the transient variation of the surface temperatures in the room. Dynamic tests in heating and cooling mode are used to validate the model. As an example of model application, the cooling ceiling system of a commercial building in Brussels is experimentally evaluated. Commissioning test results show that the influence of surfaces temperatures inside the room, especially the facade and ventilation are significant and that the radiant ceiling system must be evaluated together with its designed environment and not as a separate HVAC equipment.
39

Commissioning and validation of small subfields in Step-and-shoot IMRT

Andræ, Nils January 2008 (has links)
One of the most used irradiation techniques in modern radiation therapy is step-and-shoot IMRT. The accuracy of this technique when delivering complex dose distributions strongly depends on the size of the subfields. The aims of this study is to determine the minimum size of subfields that can be used efficiently in Step-and-Shoot IMRT, to investigate the validation process for beam delivery and treatment planning dose calculations, and to find recommendations for practical clinical implementations. Two different detectors, a CC04 ion chamber and a SFD stereotactic diode, have been used for measuring head scatter factors in air (Sc), total output factors (Scp) and dose profiles in water for a wide range of field sizes. The measurements were compared to calculations done with a pre-release version of the Nucletron MasterPlanTM v 3.1 treatment planning system that employs a novel, high resolution fluence modelling for both its pencil beam and collapsed cone dose calculation algorithms. Collimator settings were explicitly checked using FWHM film measurements with a build-up sheet of tungsten placed close to the treatment head to reduce the influence from lateral electron transport and geometrical penumbra. An analysis of the influence and sensitivity of Scp for small fields with respect to the linear accelerator source size and shape was also made. The measurements with the ionization chamber and the stereotactic diode showed good agreements with each other and with the treatment planning system calculations for field sizes larger than 2×2 cm2. For small field sizes, measurements with different detectors yielded different results. Calculations showed agreements with measurements with the smallest detector, provided careful field size calibration and commissioning of calculation parameters. Uncertainties in collimator settings and source characteristics were shown to yield large uncertainties in Scp for fields smaller than 2×2 cm2. The treatment planning system was found to properly handle small subfields but results were very sensitive to uncertainties in source size, as well as calibration and reproducibility of the collimator settings. Therefore if subfields smaller than 2×2 cm2 are to be used in IMRT extra care should be taken to determine the source characteristics and to calibrate the collimators. The volume of the detectors used for validation of such small fields and the loss of charged particle equilibrium conditions also have to be taken into consideration.
40

Implementing evaluation in the context of sustainable development (I). The planning and commissioning procedure of evaluations with sustainable development as part of a Tool Box.

Langer, Markus E., Schön, Aloisia, Egger-Steiner, Michaela, Hubauer, Irmgard January 2003 (has links) (PDF)
In the context of sustainable development, evaluations have particularly high relevance as complex issues have to be dealt with generally over an extended period of time. Furthermore, there is a growing demand to evaluate against the concept of sustainable development. Especially evaluations with sustainable development are a rather new type of evaluation, as the source of its evaluation questions and the criteria applied are rooted in the concept of sustainable development. Sustainability of a specific project or process is often highly case specific as sustainable development is determined by many often unique issues. However, evaluations would be highly inefficient, if they would have to be newly designed in every case. Thus it is necessary to determine and utilize the major issues for evaluations with sustainable development. This paper is part of a series of three papers - which can be used independently - that present the major common issues for evaluations with sustainable development in a Tool Box. The results presented here are based on outcomes of a research project funded by the "Austrian Science Fund". This paper includes the evaluation planning and commissioning procedure. It describes the steps from the idea to implementation of an evaluation with sustainable development. In the context of general requirements of evaluation planning and commissioning, the special features of evaluations with sustainable development are highlighted. (author's abstract) / Series: Research Paper Series of the Research Focus Managing Sustainability

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