Approved for public release; distribution is unlimited / The Marine Aviation Weapons and Tactics Squadron One (MAWTS-1) command requested a sleep and performance study of the instructors and students of Weapons and Tactics Instructor (WTI) course 2- 16. Specifically, MAWTS-1 leadership wanted to know whether crew rest periods were being used for sleep and whether fatigue posed a risk to personnel during the course. This thesis expanded upon prior studies in military educational environments. The WTI 2-16 study collected sleep and performance data via wrist-worn actigraphy and psychomotor vigilance tests (PVT). Sleep duration and efficiency remained high throughout the course, but participation waned before the study ended. Both instructors and students appeared to receive adequate sleep of good quality (overall mean 7.4 hrs/night). There was little variability in the sleep patterns (i.e., WTI participants were abiding by the crew rest regulations). Compliance posed a significant challenge and limited the ability to correlate sleep to performance. We also measured self-reported fatigue and mood using standardized questionnaires. Results from subjective assessments showed a significant increase in self-reported fatigue as the course progressed. This thesis outlines a detailed methodology and lessons learned for follow-on studies of this type and recommends improvements to future studies. / Major, United States Marine Corps

This thesis discusses aspects of a novel solar concentrating photovoltaic / thermal (PV/T) collector that has been designed to produce both electricity and hot water. The motivation for the development of the Combined Heat and Power Solar (CHAPS) collector is twofold: in the short term, to produce photovoltaic power and solar hot water at a cost which is competitive with other renewable energy technologies, and in the longer term, at a cost which is lower than possible with current technologies. To the author’s knowledge, the CHAPS collector is the first PV/T system using a reflective linear concentrator with a concentration ratio in the range 20-40x. The work contained in this thesis is a thorough study of all facets of the CHAPS collector, through a combination of theoretical and experimental investigation. A theoretical discussion of the concept of ‘energy value’ is presented, with the aim of developing methodologies that could be used in optimisation studies to compare the value of electrical and thermal energy. Three approaches are discussed; thermodynamic methods, using second law concepts of energy usefulness; economic valuation of the hot water and electricity through levelised energy costs; and environmental valuation, based on the greenhouse gas emissions associated with the generation of hot water and electricity. It is proposed that the value of electrical energy and thermal energy is best compared using a simple ratio. Experimental measurement of the thermal and electrical efficiency of a CHAPS receiver was carried out for a range of operating temperatures and fluid flow rates. The effectiveness of internal fins incorporated to augment heat transfer was examined. The glass surface temperature was measured using an infrared camera, to assist in the calculation of thermal losses, and to help determine the extent of radiation absorbed in the cover materials. FEA analysis, using the software package Strand7, examines the conductive heat transfer within the receiver body to obtain a temperature profile under operating conditions. Electrical efficiency is not only affected by temperature, but by non-uniformities in the radiation flux profile. Highly non-uniform illumination across the cells was found to reduce the efficiency by about 10% relative. The radiation flux profile longitudinal to the receivers was measured by a custom-built flux scanning device. The results show significant fluctuations in the flux profile and, at worst, the minimum flux intensity is as much as 27% lower than the median. A single cell with low flux intensity limits the current and performance of all cells in series, causing a significant drop in overall output. Therefore, a detailed understanding of the causes of flux non-uniformities is essential for the design of a single-axis tracking PV trough concentrator. Simulation of the flux profile was carried out using the ray tracing software Opticad, and good agreement was achieved between the simulated and measured results. The ray tracing allows the effect of the receiver supports, the gap between mirrors and the mirror shape imperfections to be examined individually. A detailed analytical model simulating the CHAPS collector was developed in the TRNSYS simulation environment. The accuracy of the new component was tested against measured data, with acceptable results. A system model was created to demonstrate how sub components of the collector, such as the insulation thickness and the conductivity of the tape bonding the cells to the receiver, can be examined as part of a long term simulation.

The Pressure-Volume-Temperature (PVT) for polymer/gas solutions is an important fundamental property of which accurate data measurement has not been reported until recently. The diffusivity, solubility, and surface tension are critical physical properties of polymer/gas solutions in understanding and controlling polymer processing such as, foaming, blending, and extracting reaction. However, the determination of these properties relies on accurate PVT data as a prerequisite. Due to the difficulties involved in measuring the specific volume while maintaining a sufficiently high pressure and temperature to achieve a single-phase polymer/gas solution, accurate PVT data or volume swelling measurement of polymer/gas solutions is not yet available. In this research, a new methodology was proposed and developed for direct measuring the PVT properties of polymer melts saturated with high-pressure gas at elevated temperatures. The ultimate goal is to develop and construct an apparatus that would provide more accurate fundamental properties through PVT measurement to the foaming industry, which is heavily involved with polymer/gas mixtures.

The Pressure-Volume-Temperature (PVT) for polymer/gas solutions is an important fundamental property of which accurate data measurement has not been reported until recently. The diffusivity, solubility, and surface tension are critical physical properties of polymer/gas solutions in understanding and controlling polymer processing such as, foaming, blending, and extracting reaction. However, the determination of these properties relies on accurate PVT data as a prerequisite. Due to the difficulties involved in measuring the specific volume while maintaining a sufficiently high pressure and temperature to achieve a single-phase polymer/gas solution, accurate PVT data or volume swelling measurement of polymer/gas solutions is not yet available. In this research, a new methodology was proposed and developed for direct measuring the PVT properties of polymer melts saturated with high-pressure gas at elevated temperatures. The ultimate goal is to develop and construct an apparatus that would provide more accurate fundamental properties through PVT measurement to the foaming industry, which is heavily involved with polymer/gas mixtures.

This thesis is composed of two designs: a PT (process, temperature) detector for 2¡ÑVDD output buffer with slew rate compensation, and a slew rate self-adjusting 2¡ÑVDD output buffer with PVT compensation. In the first topic, a PT detector for 2¡ÑVDD output buffer with slew-rate compensa-tion is proposed. The driving current of 2¡ÑVDD output stages varies provided that the process and temperature conditions are different. For example, the driving current of 2¡ÑVDD output stage will be low at poor PVT corners. By contrast, the driving current will be high at good PVT corners. The process corner and temperature of NMOS and PMOS should be detected by threshold voltage variation thereof, respectively, such that the slew rate compensation is feasible. The proposed sensors will carry out the PT de-tection and compensate the driving current based on the detected corner, such that the slew rate variation of the output stage will be reduced. The second topic is a slew rate self-adjusting 2¡ÑVDD output buffer with PVT compensation. An NMOS and PMOS process detector is proposed to detect the process corners of NMOS and PMOS, respectively, while the voltage and temperature sensor is proposed to detect the voltage and temperature variations by body effect.

Since the plus fraction of reservoir fluids has some uncertainty in its molecular weight and critical properties, equation-of-state, EOS, are generally not predictive without tuning its parameters to match experimental data. Tuning of the EOS is found to be the best method for improving the predictions of compositional reservoir simulators. The proposed strategy for tuning EOS consists of seven steps: (1) split the laboratory plus fraction to single carbon number groups, SCN, usually up to SCN 44; the last component will be C45+, (2) use set of correlations to calculate the critical properties and acentric factor for each SCN group, (3) match the saturation pressure at reservoir temperature by altering the measured value of the molecular weight of the plus fraction using the extended composition, (4) group SCN groups to multiple carbon number groups, MCN, (5) assign critical properties and acentric factor for each MCN group, (6) rematch the saturation pressure at reservoir temperature using the grouped composition, and (7) match the volumetric data by regressing on volume shift parameters of all components in grouped composition. This research shows an accurate method to split the plus fraction to SCN groups. The most accurate set of correlations to calculate the critical properties and acentric factor for each SCN group that will result in a small adjustment for the molecular weight of the plus fraction when saturation pressure is matched using the extended composition. The proposed strategy groups the extended composition to eight pseudocomponents. The binary interaction coefficients between hydrocarbons and between hydrocarbons and non-hydrocarbons are set to zero which dramatically reduces the simulation time. The strategy proposed in this research for tuning EOS to match experimental data has been tested for a wide range of C7+ mole% (4 – 25) which covers gas condensate and volatile oil samples. Also, using this strategy to tune EOS at reservoir temperature will accurately predict the fluid properties at separator conditions and saturation pressures at different temperatures. The scope of this research is to come up with an accurate and systematic technique for tuning an EOS for use in compositional simulation.

Made available in DSpace on 2016-12-08T17:19:32Z (GMT). No. of bitstreams: 1 RESUMO Altair.pdf: 63095 bytes, checksum: 77afe61ac47f2c1f354dcfc5c61d23f7 (MD5) Previous issue date: 2005-07-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / One of the aims of this work is to determine the model test bulk used by the injection molding process. The mathematical model governing the plate solidification time of the gate together with the beginning of the stabilization of the cavity bulk. In this test a copolymer styreneacrylonitrile (SAN) will be used. In order to develop the model tests, the material had to be dried to establish some parameters like: injection pressure, injection time, temperature of the different stages as well as moulding temperature. The variable parameters were the time and the discharge pressure. As the model tests were fully develoved, bulks were determined, first for the mould cavity and branches and next for the single cavity which was separated from the branches. The variations of the cavity bulkfor the different discharge pressures and the standard deviation were graphically represented due to the time deviation of the discharge. The results shoved that the time the bulk cavity begins to stabilize matches the calculated time, for the nonflow temperature, as well as the glass part temperature, the discharge pressure. / Este trabalho tem como objetivo, determinar a variação da massa de corpos de prova fabricado pelo processo de moldagem de injeção. A partir de equações que tratam da solidificação de placas, será correlacionado o tempo de solidificação do canal de ataque com o tempo de início de estabilização da massa da cavidade. Para o desenvolvimento experimental será utilizado um copolímero estireno-acrilonitrila (SAN). Para a realização dos corpos de prova, foi necessário secar o material, fixar alguns parâmetros de processos, tais como; pressão de injeção, tempo de injeção, temperatura nos diferentes estágios e temperatura de molde. Os parâmetros variáveis foram: o tempo e a pressão de recalque. Com os corpos de prova prontos, suas massas foram determinadas, inicialmente para ambas, cavidades e canais de distribuição, em seguida, para a cavidade individualmente que foi separada dos canais de dsitribuição. A variação da massa da cavidade, para as diferente pressões de recalque e seus respectivos desvios padrão foram representados gráficamente em função da variação do tempo de recalque. O tempo em que a massa da cavidade começa a estabilizar está coerente com os tempos calculados, para a temperaturade não fluxo, e a temperatura de transição vítrea, a pressão de recalque.

O estudo do comportamento termodinâmico de polímeros, através da relação pressão-volume-temperatura (PvT), é essencial para analisar os processos físicos que ocorrem durante o seu processamento e para prever as propriedades finais dos produtos. Existem diversos estudos que comparam a precisão de várias equações de estado (EdE) na descrição do comportamento termodinâmico de polímeros. Segundo a literatura, as que usualmente apresentam os melhores resultados são as equações teóricas dos modelos de célula e de vazios, e as equações empíricas Tait e Hartmann- Haque (HH). Entretanto, não há trabalhos que avaliem a qualidade da estimação dos parâmetros e a sensibilidade da predição das propriedades termodinâmicas com relação aos parâmetros das equações. Além disso, há poucos estudos que contemplem a predição dos coeficientes de expansão térmica e de compressão. Com base nessas observações, o objetivo deste estudo foi apresentar uma análise mais detalhada das equações de estado Tait, HH, MCM (modelo de célula modificado) e SHT (teoria de vazios simplificada) na predição do comportamento PvT de polímeros, para os estados físicos fundido e sólido. As EdE foram analisadas com relação à: (i) qualidade na estimação dos parâmetros, (ii) sensibilidade das suas predições para cada um dos seus parâmetros, (iii) qualidade na predição do volume específico, e (iv) qualidade na predição do coeficiente de expansão térmica isobárica e da compressibilidade isotérmica. Os resultados apontaram que todas as equações de estado proporcionaram uma descrição satisfatória do comportamento PvT no estado fundido, com uma leve superioridade da EdE Tait. As EdE apresentaram baixos desvios padrão na estimação dos parâmetros, sensibilidade paramétrica adequada e predições plausíveis do volume específico, do coeficiente de expansão térmica e da compressibilidade isotérmica, com exceção da EdE Tait que apresentou uma predição do coeficiente de expansão térmica que não está de acordo com o esperado teoricamente. No estado sólido, a equação de estado Tait exibiu desempenho semelhante ao apresentado para o estado fundido na predição de dados PvT. A EdE HH apresentou resultados satisfatórios para os polímeros amorfos e dificuldade no ajuste da curva PvT de polímeros semicristalinos. / The study of the pressure-volume-temperature (PvT) behavior of polymers is essential to the analysis of the physical processes that occur during processing, and to predict the properties of the final products. In literature, there are several studies that compare the accuracy of various equations of state (EoS) in describing the PvT behavior of polymers, indicating that the best results are usually obtained with the theoretical equations of cell and hole models, and the Tait and Hartmann-Haque (HH) empirical equations. However, most of these studies do not provide information about the quality of the estimated parameters or the sensitivity of the prediction of thermodynamic properties to the parameters of the equations. Furthermore, there are few studies exploring the prediction of thermal expansion and compression coefficients. Based on these observations, the objective of this study is to deepen the analysis of Tait, HH, MCM (modified cell model) and SHT (simplified hole theory) equations of state in prediction the PvT behavior of polymers, for molten and solid states. In this sense, the EoS were analyzed with respect to: (i) quality in the estimation of its parameters, (ii) sensitivity of their predictions to each of its parameters, (iii) quality of the prediction of the specific volume, and (iv) quality in the prediction of isobaric thermal expansion coefficient and isothermal compressibility. The results showed that all equations of state provided an adequated description of the PvT behavior in the molten state, with light superiority of the Tait EoS. All equations presented low standard deviations in the estimation of parameters, adequate sensitivity of its parameters and plausible prediction of specific volume, thermal expansion, and isothermal compression coefficients, except Tait EoS that show a prediction of the dependence of the thermal expansion coefficient with the temperature that is not in agreement with the theoretical expectations. In the solid state, the Tait equation exhibited performance similar to the one obtained for the molten state. HH EoS showed a satisfactory result for amorphous polymers and a difficulty in fitting the PvT curve of semicrystalline polymers.

O estudo do comportamento termodinâmico de polímeros, através da relação pressão-volume-temperatura (PvT), é essencial para analisar os processos físicos que ocorrem durante o seu processamento e para prever as propriedades finais dos produtos. Existem diversos estudos que comparam a precisão de várias equações de estado (EdE) na descrição do comportamento termodinâmico de polímeros. Segundo a literatura, as que usualmente apresentam os melhores resultados são as equações teóricas dos modelos de célula e de vazios, e as equações empíricas Tait e Hartmann- Haque (HH). Entretanto, não há trabalhos que avaliem a qualidade da estimação dos parâmetros e a sensibilidade da predição das propriedades termodinâmicas com relação aos parâmetros das equações. Além disso, há poucos estudos que contemplem a predição dos coeficientes de expansão térmica e de compressão. Com base nessas observações, o objetivo deste estudo foi apresentar uma análise mais detalhada das equações de estado Tait, HH, MCM (modelo de célula modificado) e SHT (teoria de vazios simplificada) na predição do comportamento PvT de polímeros, para os estados físicos fundido e sólido. As EdE foram analisadas com relação à: (i) qualidade na estimação dos parâmetros, (ii) sensibilidade das suas predições para cada um dos seus parâmetros, (iii) qualidade na predição do volume específico, e (iv) qualidade na predição do coeficiente de expansão térmica isobárica e da compressibilidade isotérmica. Os resultados apontaram que todas as equações de estado proporcionaram uma descrição satisfatória do comportamento PvT no estado fundido, com uma leve superioridade da EdE Tait. As EdE apresentaram baixos desvios padrão na estimação dos parâmetros, sensibilidade paramétrica adequada e predições plausíveis do volume específico, do coeficiente de expansão térmica e da compressibilidade isotérmica, com exceção da EdE Tait que apresentou uma predição do coeficiente de expansão térmica que não está de acordo com o esperado teoricamente. No estado sólido, a equação de estado Tait exibiu desempenho semelhante ao apresentado para o estado fundido na predição de dados PvT. A EdE HH apresentou resultados satisfatórios para os polímeros amorfos e dificuldade no ajuste da curva PvT de polímeros semicristalinos. / The study of the pressure-volume-temperature (PvT) behavior of polymers is essential to the analysis of the physical processes that occur during processing, and to predict the properties of the final products. In literature, there are several studies that compare the accuracy of various equations of state (EoS) in describing the PvT behavior of polymers, indicating that the best results are usually obtained with the theoretical equations of cell and hole models, and the Tait and Hartmann-Haque (HH) empirical equations. However, most of these studies do not provide information about the quality of the estimated parameters or the sensitivity of the prediction of thermodynamic properties to the parameters of the equations. Furthermore, there are few studies exploring the prediction of thermal expansion and compression coefficients. Based on these observations, the objective of this study is to deepen the analysis of Tait, HH, MCM (modified cell model) and SHT (simplified hole theory) equations of state in prediction the PvT behavior of polymers, for molten and solid states. In this sense, the EoS were analyzed with respect to: (i) quality in the estimation of its parameters, (ii) sensitivity of their predictions to each of its parameters, (iii) quality of the prediction of the specific volume, and (iv) quality in the prediction of isobaric thermal expansion coefficient and isothermal compressibility. The results showed that all equations of state provided an adequated description of the PvT behavior in the molten state, with light superiority of the Tait EoS. All equations presented low standard deviations in the estimation of parameters, adequate sensitivity of its parameters and plausible prediction of specific volume, thermal expansion, and isothermal compression coefficients, except Tait EoS that show a prediction of the dependence of the thermal expansion coefficient with the temperature that is not in agreement with the theoretical expectations. In the solid state, the Tait equation exhibited performance similar to the one obtained for the molten state. HH EoS showed a satisfactory result for amorphous polymers and a difficulty in fitting the PvT curve of semicrystalline polymers.

Abstract To prevent that the climate influences reaches critical and irreversible levels in the near future, a change in our energy consumption and our energy sources is required. It will be a combination of multiple system solutions and several types of renewable sources, both at a personal and national levels. Every hour, the sun shines at the earth with the same amount that the world's population needs in a year. It is clearly a small part of this that we could use, but it is easy to see the potential. Evertech is a company in Umeå, whose strategy is to develop products to extract and recycle heat energy from the solar renewable resource. The company has several products and all are based on a heat exchange panel. Together with the company the possibility of combining a solar module with Evertech's solar panel was tested for a hybrid to get better effect on the solar cell by cooling. Hybrids are also called PVT-modules (photovoltaic thermal). A system setup was made with a simple prototype to measure surface temperature and power difference when the solar cell was cooled by the heat exchanger absorber. The measurement study showed an increased effect of 8 % on average and a maximum of 15 %. At the time of maximum, a surface temperature difference between the solar cell and the hybrid was determined to 20°C while the average was at 15°C. A temperature gradient at the cooled module was detected, which inhibited the power increase. This indicates that a future product would have the ability to obtain higher values.  By combining the solar hybrid with a geothermal heating system, one could secure both the own heat supply and the electricity supply and at the same time have the possibility of recharge the mountain. This and how the systems can benefit from each other were studied in the simulation program Polysun. The primary goal of using a hybrid system is to create as high efficiency as possible on the solar cells and to improve the SPF value of the heat pump by allowing the heat carrier to circulate through the hybrids. The difference between the SPF-value of a hybrid system in conjunction with a geothermal system was 4.2 against the geothermal system 2.7. To cover up the increased electricity consumption that the circulation meant and the heat losses against a solar collector system did not become a problem. The results of the simulations and the economic study show that a PVT-panel built on Evertech's ETX-panel together with geothermal heat has equally good conditions for managing as solar cells or traditional solar collectors. The repayment period for a PVT module was 13,8 years for a 20 % solvency payment. For a solar cell plant of the same size it became 14,5 years. The PVT had the best return on investment of 1,2 % and an annual gain of 2000 Swedish kronor of the compared systems.