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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

Scaling of the ferroelectric field effect transistor and programming concepts for non-volatile memory applications

Fitsilis, Michael. Unknown Date (has links) (PDF)
Techn. Hochsch., Diss., 2005--Aachen.
22

Economic and Environmental Analysis of Excess Heat at Pulp Mills

Kullmann, Felix January 2018 (has links)
European industries have realized that a reduction of primary energy usage is not only a European requirement but can also be of great economic interest. Especially both energy and resource intensive industries like the pulp and paper industry will benefit. Industrial excess heat as a by-product of industrial processes needing energy has a great potential to be a key factor in reducing primary energy usage. Both excess heat utilization and heat integration are potential ways for Kraft pulp mills to increase their energy efficiency, to decrease their primary energy use and thus green-house gas emission, and to support the pulp and paper industry to achieve sustainability goals and meet EU regulations. This thesis examines the total excess heat potential in the Swedish Kraft pulp industry through pinch analysis and optimization on a modelled average Swedish Kraft pulp mill (FRAM). Different excess heat recovery technologies (EHRTs) are identified based on their applicability and are evaluated regarding their environmental and economic benefits for the Swedish pulp industry by using the energy price and carbon scenarios tool (ENPAC tool). An excess heat potential in the Swedish Kraft pulp mill industry of 2,03 TWh at 60°C, and 3,53 TWh at 25°C is found in this study. Heat delivery to the district heating network (DH), cooling delivery to the district cooling network (DC), electricity generation with a condensing turbine (CT), phase-change material engine (PCM) and organic Rankine cycle (ORC) are identified as suitable excess heat recovery technologies for Swedish Kraft pulp mills. A payback time calculation in this study found the condensing turbine as the EHRT to be of highest economic benefit in 2018 (less than 3 years). With predicted future energy prices of the years 2030, 2040 and 2050 all considered recovery technologies become economically feasible (payback time of less than 3 years). The CT and combinations of CT with DH and DC are furthermore the recovery technologies with the highest CO2 savings of 100.000 t/a in 2018. All in all, this study suggests investing in a CT, or combinations of it with DH and DC, to create the greatest economic and environmental benefits in 2018. With future price changes on the energy market and an uncertain future energy demand an investment in combinations of recovery technologies generating both heat, cooling and electricity is found to be the most sustainable choice.
23

Functional Modeling of C2

Prytz, Erik January 2009 (has links)
Command and Control (C2) refers to the process or function of commanding and controlling military or civilian units. For most military context C2 is exercised in an adversarial environment where two or more forces are fighting against each other. In these situations it is desirable to constrain the adversarial forces in order to prevent them from achieving their objectives. By maintaining an accurate view of the possible dependencies and couplings within the own forces and between the own and adversarial forces, constraints can be managed and coordinated. The purpose of this thesis is to develop a model that is capable of capturing these dependencies and couplings. This model is developed using the Functional Resonance Analysis Method (FRAM; Hollnagel, 2004). FRAM builds on the assumption that all parts of the system can be described as functional units. These functional units can then be linked together to form large systems. The links themselves are defined by how a function may affect other functions or in turn be affected by them. This enables the model to incorporate complex interactions within the system as well as between two adversarial systems. The microworld “Dynamiskt Krigsspel för Experiment” (DKE) was used to develop the model. A scenario with two teams battling in this adversarial microworld setting was analyzed in detail for this purpose. The developed model uses three different layers, or resolutions, of functions to capture all potential couplings between functions. The lowest level of functions, called the tactical level, is the physical actions of the units in the microworld. The next level, the operational level, concerns the more overarching goals for which the tactical functions are used. Last, the strategic level consists of the C2 functions, such as data collection, sensemaking and planning. The developed model is then applied to the scenario in DKE and shown to be able to describe and explain all actions by the two adversary systems as well as the couplings and dependencies between them.
24

Přístupový terminál se čtečkou RFID / RFID equipped security terminal

Vařečka, Radek January 2008 (has links)
The concept proposal of the RFID security terminal is described in this Master Thesis. The RFID identification and its usage are analyzed at first. The description of the selected fitting circuits, communication bus as well as its parameters follows. The practical realization, proposed module design and designed printed circuit board is described afterwards. Several problems found during activation phase are analyzed in the chapter describing the practical module realization. The problem resolution is mentioned as well. The practical prove of the real module parameters and differences compared to the designed values are described at the end of this Master Thesis.
25

Behaviour of Inelastic Multi-Storey Building Frames Subjected to Strong Ground Motions

Guru, Badri Prasad 06 1900 (has links)
The theoretical and experimental investigations presented in this thesis are primarily related to the dynamic response of inelastic multi-storey building frames subjected to strong ground motions. The main purpose is to investigate, both analytically and experimentally, those aspects of the dynamic response characteristics which are of importance in aseismic design. In the first part of the thesis, the various parameters pertaining to the structural system are varied in a systematic manner and an assessment is made of the influence of this variation on the maximum response characteristics of the dynamic system. The second part of the thesis consists of an experimental investigation into the inelastic dynamic response of multi-storey frames. The comparison of experimentally obtained inelastic response and that predicted theoretically indicated a good agreement between the two. / Thesis / Doctor of Philosophy (PhD)
26

Feroelektrika v elektrickém poli / Ferroelectrics in an electric field

Pavelka, Petr January 2012 (has links)
The submitted thesis describes characteristics and use of ferroelectric materials which find their utilization in electrotechnical and electronics industry. The thesis is mainly aimed at their behaviour in the electrical field at various intensity. The method using an osciloscope is selected for measuring. For the main measuring in part of this thesis was produced experimental wafer with five samples which were subsequently mesuared. The VEE PRO program was used for creating of collecting datas for histeresis loop and it’s functionality was checked on wafer with five examples in measuring. During this measuring was also measured electric tension dependence of components of complex permittivity.
27

Análise dos métodos A3, FRAM e RCA aplicados para a solução de problemas em ambiente hospitalar

Priori, Fábio Rodrigues January 2017 (has links)
A solução de problemas é parte fundamental da manutenção da qualidade e da melhoria contínua. Ao longo dos anos diversos métodos foram desenvolvidos para solucionar problemas, todavia nem todos os métodos são aplicáveis em todos os problemas ou adequados para todos os setores. Caracterizado pelo ambiente em constante mudança, o setor hospitalar possui problemas complexos, cuja solução necessita de uma abordagem adequada e robusta. Dessa forma, o presente trabalho objetiva avaliar o desempenho de três métodos normalmente utilizados para solução de problemas: A3, RCA e FRAM, quando aplicados em ambiente hospitalar. Para esse fim, os três métodos foram aplicados no mesmo processo, de prescrição e medicação, de um hospital universitário. Os resultados das aplicações foram analisados de acordo com os critérios: número total de ações de melhoria propostas, dificuldade de implementação, a possibilidade de replicação das ações entre as unidades do hospital, o tempo necessário para aplicação dos métodos, o número de envolvidos, a necessidade de capacitação da equipe e um indicador de prioridade das ações propostas. Além disso, a percepção dos profissionais da saúde em relação aos métodos foi analisada. Os resultados demonstram que, no contexto avaliado, os métodos apresentaram um bom desempenho, por terem apresentado melhorias que, em média, foram consideradas adequadas pela instituição. / Problem solving is a fundamental part for quality maintenance and continuous improvement. Through the years many methods were developed to solve problems, though these methods do not apply to every problem, or are suitable to every type of activity. Kwon for its constant changing nature, hospitals have complex problems, which need a suitable and robust approach to solve. Thus, the present study has the objective of evaluating the performance of three methods usually used for problem solving: A3, RCA and FRAM, when applied on a hospital. For this, the three methods were applied in the same process, of prescription and medication, in an academic hospital. The results were analyzed accordingly to the following criteria: the total number of improvement actions proposed, implementation difficult, replication possibility along the departments of the hospital, the time needed to apply the methods, the number of people involved, the need of training for the team and an indicator for prioritization. Besides that, the health sector workers’ perception regards the methods was analyzed. The results evidence that, in the studied context, the methods had good performance, because introduced improvements that, on average, were considered suitable for the institution.
28

Framework para avaliação de projetos de melhoria contínua sob a visão da complexidade : um estudo na área da saúde

Ferreira, Dayane Maximiano Carvalho January 2018 (has links)
Sistemas de saúde têm sido cada vez mais exigidos a serem mais eficientes, o que encorajou o uso de iniciativas de melhoria de processos. A partir de então, a Produção Enxuta (PE) surgiu como uma abordagem amplamente utilizada. Alguns resultados insatisfatórios da PE podem ser, parcialmente, explicados pela falta de considerar a complexidade dos serviços de saúde. Os sistemas de saúde são classificados como sistemas sócio-técnicos complexos (SSTC) devido à incerteza, diversidade e interações não-lineares. De acordo com a literatura, as implementações de Lean em serviços de saúde geralmente envolvem Kaizen, que tende a produzir ganhos significativos de eficiência e segurança através de mudanças relativamente pequenas e localizadas. Contudo, as melhorias locais podem implicar resultados globais indesejados, uma vez que as interações entre os elementos de sistemas complexos podem não ser lineares. Para isso, este trabalho desenvolve e aplica uma framework que visa avaliar projetos de melhoria em SSTC. O estudo foi realizado em uma unidade de internação de um hospital escola. As interações entre os projetos foram modeladas através do desenvolvimento de um diagrama de loop causal, o qual representou variáveis relacionadas a cinco projetos de melhoria analisados e um modelo FRAM. Os projetos também foram avaliados quanto ao seu impacto no sistema e sua adesão a boas práticas em Kaizen, identificadas na literatura. A framework demonstrou-se eficaz em elencar as variáveis para que possam influenciar positivamente os resultados dos projetos e embasar recomendações para a condução de novos projetos de melhoria por meio de uma visão sistêmica. / Healthcare systems have been increasingly demanded to be more efficient, which has encouraged the use of process improvement initiatives. From these, lean production has emerged as a widely used approach. Some disappointing results of lean production can be partially due to the lack of consideration of the complexity of healthcare. Health systems are classified as Complex socio-technical systems (CSTS) due to the uncertainty, diversity, and non-linear interactions. According to the literature, the implementation of Lean in healthcare usually involves Kaizen, which tends to produce significant gains in efficiency and safety through relatively small and localized changes. However, local improvements may imply unwanted overall results, since interactions between elements of complex systems may not be linear. For this, this work develops and applies a framework that aims to evaluate improvement projects in CSTC. The study was performed in an in-patient surgical ward of a teaching hospital. The interactions between the projects were modelled through the development of a causal-loop diagram, which accounted for variables related to all five projects, and a FRAM model. The projects were also evaluated as to their impact on the system and their adherence to good Kaizen practices identified in the literature. The framework proved to be effective in highlighting the variables so that they can positively influence the projects results and support recommendations for conducting new improvement projects through a systemic view.
29

Análise dos métodos A3, FRAM e RCA aplicados para a solução de problemas em ambiente hospitalar

Priori, Fábio Rodrigues January 2017 (has links)
A solução de problemas é parte fundamental da manutenção da qualidade e da melhoria contínua. Ao longo dos anos diversos métodos foram desenvolvidos para solucionar problemas, todavia nem todos os métodos são aplicáveis em todos os problemas ou adequados para todos os setores. Caracterizado pelo ambiente em constante mudança, o setor hospitalar possui problemas complexos, cuja solução necessita de uma abordagem adequada e robusta. Dessa forma, o presente trabalho objetiva avaliar o desempenho de três métodos normalmente utilizados para solução de problemas: A3, RCA e FRAM, quando aplicados em ambiente hospitalar. Para esse fim, os três métodos foram aplicados no mesmo processo, de prescrição e medicação, de um hospital universitário. Os resultados das aplicações foram analisados de acordo com os critérios: número total de ações de melhoria propostas, dificuldade de implementação, a possibilidade de replicação das ações entre as unidades do hospital, o tempo necessário para aplicação dos métodos, o número de envolvidos, a necessidade de capacitação da equipe e um indicador de prioridade das ações propostas. Além disso, a percepção dos profissionais da saúde em relação aos métodos foi analisada. Os resultados demonstram que, no contexto avaliado, os métodos apresentaram um bom desempenho, por terem apresentado melhorias que, em média, foram consideradas adequadas pela instituição. / Problem solving is a fundamental part for quality maintenance and continuous improvement. Through the years many methods were developed to solve problems, though these methods do not apply to every problem, or are suitable to every type of activity. Kwon for its constant changing nature, hospitals have complex problems, which need a suitable and robust approach to solve. Thus, the present study has the objective of evaluating the performance of three methods usually used for problem solving: A3, RCA and FRAM, when applied on a hospital. For this, the three methods were applied in the same process, of prescription and medication, in an academic hospital. The results were analyzed accordingly to the following criteria: the total number of improvement actions proposed, implementation difficult, replication possibility along the departments of the hospital, the time needed to apply the methods, the number of people involved, the need of training for the team and an indicator for prioritization. Besides that, the health sector workers’ perception regards the methods was analyzed. The results evidence that, in the studied context, the methods had good performance, because introduced improvements that, on average, were considered suitable for the institution.
30

Framework para avaliação de projetos de melhoria contínua sob a visão da complexidade : um estudo na área da saúde

Ferreira, Dayane Maximiano Carvalho January 2018 (has links)
Sistemas de saúde têm sido cada vez mais exigidos a serem mais eficientes, o que encorajou o uso de iniciativas de melhoria de processos. A partir de então, a Produção Enxuta (PE) surgiu como uma abordagem amplamente utilizada. Alguns resultados insatisfatórios da PE podem ser, parcialmente, explicados pela falta de considerar a complexidade dos serviços de saúde. Os sistemas de saúde são classificados como sistemas sócio-técnicos complexos (SSTC) devido à incerteza, diversidade e interações não-lineares. De acordo com a literatura, as implementações de Lean em serviços de saúde geralmente envolvem Kaizen, que tende a produzir ganhos significativos de eficiência e segurança através de mudanças relativamente pequenas e localizadas. Contudo, as melhorias locais podem implicar resultados globais indesejados, uma vez que as interações entre os elementos de sistemas complexos podem não ser lineares. Para isso, este trabalho desenvolve e aplica uma framework que visa avaliar projetos de melhoria em SSTC. O estudo foi realizado em uma unidade de internação de um hospital escola. As interações entre os projetos foram modeladas através do desenvolvimento de um diagrama de loop causal, o qual representou variáveis relacionadas a cinco projetos de melhoria analisados e um modelo FRAM. Os projetos também foram avaliados quanto ao seu impacto no sistema e sua adesão a boas práticas em Kaizen, identificadas na literatura. A framework demonstrou-se eficaz em elencar as variáveis para que possam influenciar positivamente os resultados dos projetos e embasar recomendações para a condução de novos projetos de melhoria por meio de uma visão sistêmica. / Healthcare systems have been increasingly demanded to be more efficient, which has encouraged the use of process improvement initiatives. From these, lean production has emerged as a widely used approach. Some disappointing results of lean production can be partially due to the lack of consideration of the complexity of healthcare. Health systems are classified as Complex socio-technical systems (CSTS) due to the uncertainty, diversity, and non-linear interactions. According to the literature, the implementation of Lean in healthcare usually involves Kaizen, which tends to produce significant gains in efficiency and safety through relatively small and localized changes. However, local improvements may imply unwanted overall results, since interactions between elements of complex systems may not be linear. For this, this work develops and applies a framework that aims to evaluate improvement projects in CSTC. The study was performed in an in-patient surgical ward of a teaching hospital. The interactions between the projects were modelled through the development of a causal-loop diagram, which accounted for variables related to all five projects, and a FRAM model. The projects were also evaluated as to their impact on the system and their adherence to good Kaizen practices identified in the literature. The framework proved to be effective in highlighting the variables so that they can positively influence the projects results and support recommendations for conducting new improvement projects through a systemic view.

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