Rozprawy doktorskie na temat „Thermal time”
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Feldgoise, Jeffrey. "Thermal design through space and time". Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/65983.
Pełny tekst źródłaIncludes bibliographical references (p. 89-90).
One of the primary roles of architecture is to control the environment at the service of a building's inhabitants. Thermal qualities are a significant factor in the overall experience one has inside and outside a building. However, thermal issues are not often considered within the context of the architectural design process, resulting in buildings that are not responsive to thermal concerns. Heat has the potential to influence the form of architectural space. The methods by which architects can use thermal energy as a formative element in design is open to further exploration. In this thesis, I explore new methods for architects to describe thermal intentions and visualize thermal qualities of design proposals. Beyond the economic issue of energy conservation, the thermal qualities of building spaces affect the quality of human inhabitation. The capability to describe and visualize heat would allow architects to adjust the building's thermal characteristics to modify a person's experience of the place. With a more complete understanding of thermal qualities of their building proposals, architects would be able to design for the complete gamut of thermal sensations that humans can experience. What is needed is a working vocabulary that describes the range of thermal conditions possible in buildings. In this work, I describe a vocabulary for a building's thermal qualities using four sets of measurable, opposing terms: open versus protected, bright versus dim, warm versus cool, and active versus still. Next, I then articulate the thermal qualities of a co-housing project to create a thermal experience that enhances the community aspects of co-housing. Using a variety of visualization techniques, I verify that the design proposal is achieving the intended thermal goals. Using the knowledge gained from this and future thermal design exercises, we can begin to reflect on the general relationships between thermal phenomena and physical building forms, learning about the thermal qualities of architecture.
Jeffrey Feldgoise.
M.Arch.
Alshatshati, Salahaldin Faraj. "Estimating Envelope Thermal Characteristics from Single Point in Time Thermal Images". University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1512648630005333.
Pełny tekst źródłaMichiorri, Andrea. "Power system real-time thermal rating estimation". Thesis, Durham University, 2010. http://etheses.dur.ac.uk/469/.
Pełny tekst źródłaGaffney, Eamonn Andrew. "Aspects of imaginary time thermal field theory". Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627526.
Pełny tekst źródłaLeVett, Marshall Allan. "Parallel Time-Marching for Fluid-Thermal-Structural Interactions". The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1452178897.
Pełny tekst źródłaBabich, Francesco. "Thermal comfort in non-uniform environments : real-time coupled CFD and human thermal regulation modelling". Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/32835.
Pełny tekst źródłaAcomb, Simon. "Applications of nonlinear dynamics to time dependent thermal convection". Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305477.
Pełny tekst źródłaCosma, Andrei Claudiu. "Real-Time Individual Thermal Preferences Prediction Using Visual Sensors". Thesis, The George Washington University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=13422566.
Pełny tekst źródłaThe thermal comfort of a building’s occupants is an important aspect of building design. Providing an increased level of thermal comfort is critical given that humans spend the majority of the day indoors, and that their well-being, productivity, and comfort depend on the quality of these environments. In today’s world, Heating, Ventilation, and Air Conditioning (HVAC) systems deliver heated or cooled air based on a fixed operating point or target temperature; individuals or building managers are able to adjust this operating point through human communication of dissatisfaction. Currently, there is a lack in automatic detection of an individual’s thermal preferences in real-time, and the integration of these measurements in an HVAC system controller.
To achieve this, a non-invasive approach to automatically predict personal thermal comfort and the mean time to discomfort in real-time is proposed and studied in this thesis. The goal of this research is to explore the consequences of human body thermoregulation on skin temperature and tone as a means to predict thermal comfort. For this reason, the temperature information extracted from multiple local body parts, and the skin tone information extracted from the face will be investigated as a means to model individual thermal preferences.
In a first study, we proposed a real-time system for individual thermal preferences prediction in transient conditions using temperature values from multiple local body parts. The proposed solution consists of a novel visual sensing platform, which we called RGB-DT, that fused information from three sensors: a color camera, a depth sensor, and a thermographic camera. This platform was used to extract skin and clothing temperature from multiple local body parts in real-time. Using this method, personal thermal comfort was predicted with more than 80% accuracy, while mean time to warm discomfort was predicted with more than 85% accuracy.
In a second study, we introduced a new visual sensing platform and method that uses a single thermal image of the occupant to predict personal thermal comfort. We focused on close-up images of the occupant’s face to extract fine-grained details of the skin temperature. We extracted manually selected features, as well as a set of automated features. Results showed that the automated features outperformed the manual features in all the tests that were run, and that these features predicted personal thermal comfort with more than 76% accuracy.
The last proposed study analyzed the thermoregulation activity at the face level to predict skin temperature in the context of thermal comfort assessment. This solution uses a single color camera to model thermoregulation based on the side effects of the vasodilatation and vasoconstriction. To achieve this, new methods to isolate skin tone response to an individual’s thermal regulation were explored. The relation between the extracted skin tone measurement and the skin temperature was analyzed using a regression model.
Our experiments showed that a thermal model generated using noninvasive and contactless visual sensors could be used to accurately predict individual thermal preferences in real-time. Therefore, instantaneous feedback with respect to the occupants' thermal comfort can be provided to the HVAC system controller to adjust the room temperature.
Mackwood, Andrew. "Numerical simulations of thermal processes and welding". Thesis, University of Essex, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272572.
Pełny tekst źródłaHuang, Huang. "Power and Thermal Aware Scheduling for Real-time Computing Systems". FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/610.
Pełny tekst źródłaYu, Ying Diana. "Real-time computer control for wafer in rapid thermal processing". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq20891.pdf.
Pełny tekst źródłaRogers, John Ashley. "Real time impulsive stimulated thermal scattering of thin polymer films". Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/13130.
Pełny tekst źródłaTitle as it appears in the M.I.T. Graduate List, Feb. 1992: Real time impulsive stimulated thermal scattering from supported thin polymer films.
Includes bibliographical references (p. 163-165).
by John Ashley Rogers.
M.S.
Daniel, Kyle Andreas. "Space-time Description of Supersonic Jets with Thermal Non-uniformity". Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/95942.
Pełny tekst źródłaDoctor of Philosophy
A more complete understanding of the intense noise sources present in supersonic jet plumes is of value to both government and industry, and is a necessary step towards optimizing noise reduction techniques. Tactical aircraft that operate on the deck of aircraft carriers expose Navy personnel to dangerously high levels of noise that often results in permanent hearing damage. Supersonic jet noise reduction is also of relevance to the recent efforts to revitalize supersonic air transport over land. For supersonic air transport to become a reality, the noise produced by these future aircraft during takeoff and landing must meet the increasingly stringent community noise requirements. Fundamental jet noise research is needed to guide the design of future engine architectures for these aircraft to ensure their commercial success. The research presented herein examines a novel noise reduction technique that involves a centered thermal non-uniformity consisting of a heated jet plume with a spot of locally cooler, slower moving air concentrated along the centerline of a Mach 1.5 jet. This temperature driven velocity deficit is shown to reduce the radiated noise by up to 2.5 dB at peak frequencies and at angles just outside of the peak directivity direction. The cause of the noise reduction is hypothesized be related to a reduction in the size of the coherent structures that radiate a majority of the noise produced by turbulent jets. This hypothesis is evaluated by examining the 'footprint' of the coherent structures in the ambient field directly outside of the jet shear layer in an area called the near-field. An indirect investigation of the near-field using a far-field informed analytic model suggests a reduction in the size of large scale structures. A direct evaluation of the space time structure of the near-field was performed using temporally resolved schlieren images. Statistical processing of the density gradient provided by the schlieren images revealed acoustically intense structures known as Mach waves and high frequency acoustic waves. These features and their sources, large scale instabilities and compactly coherent turbulence, were found to be decorrelated by the introduction of the thermal non-uniformity. These results provide strong evidence that the centered thermal non-uniformity produces a noise benefit by reducing the size of the turbulent structures.
Thomas, Kevin P. "System architecture for real time power management". Thesis, University of Bristol, 1996. http://hdl.handle.net/1983/b4d196a1-d1f8-4141-b6e3-a32eb4f2073f.
Pełny tekst źródłaRomano, Valerio. "Interaction of pulsed laser radiation with tissue : determination of the thermal damage with time resolved thermal microscopy /". Bern, 1991. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
Pełny tekst źródłaBeggs, Clive. "The use of ice thermal storage with real time electricity pricing". Thesis, De Montfort University, 1995. http://hdl.handle.net/2086/10674.
Pełny tekst źródłaRiedel, Gernot Jurgen. "Time Resolved Raman Thermography : Thermal Dynamics of GaN-based Electronic Devices". Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520665.
Pełny tekst źródłaJelger, Pär. "High Performance Fiber Lasers with Spectral, Thermal and Life Time Control". Doctoral thesis, KTH, Laserfysik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11711.
Pełny tekst źródłaQC 20100721
Tucker, Gary. "Development and application of time-temperature integrators to thermal food processing". Thesis, University of Birmingham, 2008. http://etheses.bham.ac.uk//id/eprint/144/.
Pełny tekst źródłaNagarajan, Vivek Krishna. "REAL-TIME ASSESSMENT OF THERMAL TISSUE DAMAGE USING DIFFUSE REFLECTANCE SPECTROSCOPY". University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1494313847936136.
Pełny tekst źródłaHedbrant, Johan. "On the thermal inertia and time constant of single-family houses". Licentiate thesis, Linköpings universitet, Energisystem, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-123878.
Pełny tekst źródłaHellweg, Stefanie Hellweg Stefanie Hellweg Stefanie. "Time- and site-dependent life-cycle assessment of thermal waste treatment processes /". Berlin : dissertation.de, 2000. http://www.dissertation.de.
Pełny tekst źródłaChaturvedi, Vivek. "Leakage Temperature Dependency Aware Real-Time Scheduling for Power and Thermal Optimization". FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/870.
Pełny tekst źródłaGim, Taeweon. "Modelling and evaluation of time-varying thermal errors in machine tool elements". Thesis, Cranfield University, 1997. http://dspace.lib.cranfield.ac.uk/handle/1826/3682.
Pełny tekst źródłaMiller, Brent Adam. "Loosely Coupled Time Integration of Fluid-Thermal-Structural Interactions in Hypersonic Flows". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429828070.
Pełny tekst źródłaAbbass, Mohamed A. M. S. "Real-time Control of Ultrasound Thermal Ablation using Echo Decorrelation Imaging Feedback". University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535468911083998.
Pełny tekst źródłaGill, Arshdeep Singh. "Thermal Evolution of Moon". DigitalCommons@CalPoly, 2017. https://digitalcommons.calpoly.edu/theses/1726.
Pełny tekst źródłaMessenger, Robert K. "Modeling and Control of Surface Micromachined Thermal Actuators". Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd434.pdf.
Pełny tekst źródłaHioe, Yunior. "Mold thermal design and quasi steady state cycle time analysis in injection molding". Connect to resource, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1141840509.
Pełny tekst źródłaChen, Huifeng. "Correcting the effect of thermal ageing for Real-Time power device Temperature Estimators". Thesis, University of Newcastle Upon Tyne, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519582.
Pełny tekst źródłaMuizzu, Mohamed. "Thermal and time-dependent effects on monolithic reinforced concrete roof slab-wall joints". Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509019.
Pełny tekst źródłaSpiers, Hayley Ileana. "Time resolved x-ray diffraction and thermal imaging studies of magnesium zinc ferrites". Thesis, University College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415415.
Pełny tekst źródłaGaskill, David M. "Real-Time Auxiliary Display Devices Enhance the Performance of Thermal Array Chart Recorders". International Foundation for Telemetering, 1991. http://hdl.handle.net/10150/612938.
Pełny tekst źródłaChart recorders are needed both for producing a permanent record for post-mission analysis and for providing real-time information during a test. Immediate feedback is important when test conditions may require mid-course warnings or corrections. In the traditional galvanometer based chart recorder, the operator can look directly at the pens moving on the paper and quickly judge speed and amplitude. When using a thermal array recorder, there is a small delay between the time of printing and the time when the trace is visible. This is due to the construction of the thermal array itself. Individual printing elements are deposited on a ceramic substrate which eliminates all motion from the printing process and physically blocks the operator’s view of the printhead so that for a short time there are no visual clues as to the exact waveform position. At higher chart speed this gap only represents milliseconds of elapsed time, well below human reaction time, and therefore of no real importance. At trending speeds, however, the delay could be half a second or even more and could be a problem in some situations. The first solution offered by manufacturers of thermal array recorders was a row of LED’s that stretched across the recorder directly over the printheads and reflected printing activity in real-time and indicated the actual position of the individual waveform traces. This was found to be a satisfactory solution by most telemetrists who wanted to change to the new technology in order to take advantage of the thermal array recorder’s higher frequency response and flexible formats. While the LED array satisfies basic real-time response requirements, there are many other applications for auxiliary displays which include variable chart labeling and graphic display of waveforms.
Greenwood, David Michael. "Quantifying the benefits and risks of real-time thermal ratings in electrical networks". Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2586.
Pełny tekst źródłaPelletier, Maude. "Geomorphological, ecological and thermal time phase of permafrost degradation, Tasiapik, Nunavik (Québec, Canada)". Master's thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/25766.
Pełny tekst źródłaSix places-échantillons représentatives de la séquence temporelle écologique associée à la dégradation du pergélisol ont été sélectionnées sur un plateau silteux à pergélisol riche en glace à proximité d'Umiujaq, au Nunavik. Le présent travail a pour objectif de déterminer les changements qui se produisent dans les flux de chaleur entre les trois niveaux de l'écosystème (végétation / couverture de neige, couche active, pergélisol) ainsi que les rétroactions qui surviennent lors de la dégradation du pergélisol et à quantifier la vitesse de la transition à partir de photographies aériennes et la dendrochronologie. Pour répondre aux objectifs, la méthodologie utilisée suit le protocole du programme Adaptation et Dévelopement de l’Arctique sur le Pergélisol en Transition (ADAPT), intégrant l’analyse de données écologiques, climatiques, stratigraphiques et thermiques. Les résultats obtenus illustrent une évolution exponentielle des facteurs de dégradation du pergélisol sur une période estimée à environ 90 ans; lent durant les 60 premières années, et significativement plus rapide durant les 30 dernières années.
Six plots, representative of the regional ecological time sequence associated with permafrost degradation, were selected on a silty ice-rich permafrost plateau near Umiujaq, Nunavik. The objective of the present work is to determine the changes that occur in the flow of energy between the three layers of the ecosystem (vegetation / snow cover, active layer, permafrost) and the feedbacks that occur during the degradation of permafrost and to quantify the rate of the transition using time-lapse aerial photographs and tree ring analysis. In order to respond to these objectives, the methodology follows the ADAPT (Arctic Development and Adaptation on Permafrost in Transition) protocol, including ecological, climate, stratigraphic and thermal data analysis. The results show exponential evolution of permafrost degradation factors over a period of time of about 90 years; slowly during the first 60 years, and significantly faster during the last 30 years.
Shrestha, Kristina. "Time-Resolved Temperature Measurements and Thermal Imaging using Nano-Thermometers in Different Environments". Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1593706274306985.
Pełny tekst źródłaBin, Ja'afar Mohamad Fakri Zaky. "Domestic air conditioning in Malaysia : night time thermal comfort and occupants adaptive behaviour". Thesis, University College London (University of London), 2008. http://discovery.ucl.ac.uk/1444280/.
Pełny tekst źródłaLiao, Hao-Hsiang. "Thermal and thermoelectric properties of nanostructured materials and interfaces". Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/19198.
Pełny tekst źródłaPh. D.
Xu, Ming. "Critical current density and time-dependent magnetization of the high transition temperature superconductors". Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/30033.
Pełny tekst źródłaNagaraj, Mahavir. "Short time scale thermal mechanical shock wave propagation in high performance microelectronic packaging configuration". Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/1087.
Pełny tekst źródłaCollins, Kimberlee C. (Kimberlee Chiyoko). "Studies of non-diffusive heat conduction through spatially periodic and time-harmonic thermal excitations". Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97836.
Pełny tekst źródłaCataloged from PDF version of thesis.
Includes bibliographical references (pages 127-133).
Studies of non-diffusive heat conduction provide insight into the fundamentals of heat transport in condensed matter. The mean free paths (MFPs) of phonons that are most important for conducting heat are well represented by a material's thermal conductivity accumulation function. Determining thermal conductivity accumulation functions experimentally by studying conduction in non-diffusive regimes is a recent area of study called phonon MFP spectroscopy. In this thesis, we investigate nondiffusive transport both experimentally and theoretically to advance methods for determining thermal conductivity accumulation functions in materials. We explore both spatially periodic and time-harmonic thermal excitations as a means for probing the non-diffusive transport regime, where the Fourier heat diffusion law breaks down. Boltzmann transport equation calculations of one-dimensional (1D) spatially sinusoidal thermal excitations are performed for gray-medium and fully spectral cases. We compare our calculations to simplified transport models and demonstrate that a model based on integrating gray-medium solutions can reasonably model materials with a narrow range of dominant heat-carrying phonon MFPs. We also consider the inverse problem of determining thermal conductivity accumulation functions from experimental measurements of thermal-length-scale-dependent effective thermal conductivity. Based on experimental measurements of Si membranes of varying thickness, we reproduce the thermal conductivity accumulation function for bulk Si. To investigate materials with short phonon MFPs, we developed an experimental approach based on microfabricating 1D wire grid polarizers on the surface of a material under study. This work finds that the dominant thermal length scales in polycrystalline Bi 2Te3 are smaller than 100 nm. We also determine that even small amounts of direct sample optical excitation, which occurs when light transmits through the grating and directly excites electron-hole pairs in the substrate, can appreciably influence the measured results, suggesting that an alternate approach that prevents all direct optical excitation is preferable. To study thermal length scales smaller than 100 nm without the need for microfabrication, we develop a method for extracting high frequency response information from transient optical measurements. For a periodic heat flux input, the thermal penetration depth in a semi-infinite sample depends on the excitation frequency, with higher frequencies leading to shallower thermal penetration depths. Prior work using frequencies as high as 200 MHz observed apparent non-diffusive behavior. Our method allows for frequencies of at least 1 GHz, but we do not observe any deviation from the heat diffusion equation, suggesting that prior observations attributed to non-diffusive effects were likely the result of transport phenomena in the metal transducer.
by Kimberlee Chiyoko Collins.
Ph. D.
Zhou, Linjing. "Transient natural convection in a cavity with time-varying thermal forcing on a sidewall". Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/28833.
Pełny tekst źródłaSHA, SHI. "The Thermal-Constrained Real-Time Systems Design on Multi-Core Platforms -- An Analytical Approach". FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3713.
Pełny tekst źródłaWei, Xiaomin. "FUNDAMENTAL CHARACTERIZATION OF TRIBOLOGICAL, THERMAL, FLUID DYNAMIC AND WEAR ATTRIBUTES OF CONSUMABLES IN CHEMICAL MECHANICAL PLANARIZATION". Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/195125.
Pełny tekst źródłaVenkatasamy, Vasanth Kumar. "Analysis of in-cavity thermal and pressure characteristics in aluminum alloy die casting". Connect to this title online, 1996. http://rave.ohiolink.edu/etdc/view?acc_num=osu1100721824.
Pełny tekst źródłaJo, Young Gyun. "Development of a thermal neutron imaging facility for real time neutron radiography and computed tomography /". Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
Pełny tekst źródłaSjölund, Johannes. "Real-time Thermal Flow Predictions for Data Centers : Using the Lattice Boltzmann Method on Graphics Processing Units for Predicting Thermal Flow in Data Centers". Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70530.
Pełny tekst źródłaSmith, Robert Merrill. "Real-Time Control of Polysilicon Deposition in Single-Wafer Rapid Thermal Chemical Vapor Deposition Furnaces". NCSU, 1998. http://www.lib.ncsu.edu/theses/available/etd-19981020-131153.
Pełny tekst źródłaThis thesis describes the development of a real-time control system for depositing polysilicon films on silicon wafers by means of rapid thermal chemical vapor deposition. Results are presented which characterize the ability of the control system to deposit films of an average desired thickness and predict the film?s spatial thickness distribution.A rapid thermal chemical vapor deposition system was used to individually process wafers. During processing, a mass spectrometer monitored the chemical species present in the exhaust gases to determine the total volume of material deposited. Simultaneously, optical probes resolved the spatial temperature distribution of the wafer. The mass spectrometry and optical temperature data were combined with an Arrhenius equation to model the deposition process. Validation of the model was exsitu. After processing, film thickness measurements were made on each wafer and compared to the computer model?s predictions.Experimental results identified hydrogen, a by-product of the deposition reaction, as the metric for determining the total volume of polysilicon deposited. Process recipe control (today?s standard control technique) produced films varying over a range of 280 Å when repeatedly employed to deposit film?s of 900 Å. Application of the real-time control system produced films varying a maximum of 74 Å when attempting to deposit films of average thickness ranging from 800 to 1200 Å. Modeling results predicted the thickness of the deposited film to within 20 Å at the center of the wafer. Predictions at the wafers edge were off by a maximum of 160 Å.From the experience gained during this project, the following two recommendations are made to guide future efforts. First, the mass spectrometer?s reaction time to an event occurring in the furnace was found to be one second. Employing an optical sensor could improve control by reducing the time lag of the system. Second, designing the furnace with the necessary optical access so that the sensors can be located outside the vacuum system would greatly facilitate the accuracy and reliability of the system. This would eliminate exposure of the sensors to the high temperatures and corrosive gases present inside the furnace which can adversely affect their performance.
GOMES, LEONARDO LIMA. "EVALUATING THERMAL PLANTS IN BRAZIL STUDIND THE BEST TIME TO INVEST USING REAL OPTIONS MODELS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=2772@1.
Pełny tekst źródłaAté 1997 o Setor Elétrico Brasileiro (SEB) era basicamente um monopólio estatal administrado por empresas federais e estaduais. A partir do segundo semestre de 1997 foram iniciadas as privatizações, e em paralelo a reestruturação do setor. Antes do processo de reestruturação do SEB, o planejamento da expansão da geração era feito de forma coordenada e centralizada, com o objetivo de minimizar os custos de investimento e operação. A expansão da geração era uma variável de decisão do problema. No entanto, um dos pressupostos da reestruturação do setor foi e continua sendo a realização pelo agente privado de grande parte dos novos investimentos em geração e transmissão. Dessa maneira, a decisão sobre a expansão da geração deixa de ser centralizada e passa a depender da disposição de investimento deste agente, acarretando no aumento do nível de incertezas no processo de planejamento. Neste contexto, o presente trabalho visa estudar a dinâmica de investimentos privados em geração termelétrica no Brasil utilizando a Teoria das Opções Reais. A dinâmica de investimentos em termelétricas será estudada em três situações diferentes. Na primeira, será utilizado um modelo de opções reais / análise de decisão para determinar as estratégias de escolha do melhor momento de construção de um empreendimento considerando que há incerteza exógena na expansão da oferta de termelétricas. Na segunda, será utilizado o mesmo modelo para determinar as estratégias de momento de construção de uma termelétrica considerando que há incerteza na demanda, e que a expansão da oferta permanece constante. Na terceira, a expansão da oferta ocorre em resposta às incertezas e à interação entre os agentes. Será utilizado um modelo de opções reais / análise de decisão / teoria dos jogos. Os principais resultados obtidos no trabalho foram os prêmios de risco exigidos pelo investidor para realizar o investimento imediato e a determinação do melhor momento de investimento em função de algumas variáveis do problema. Foi possível comparar as diferentes situações estudadas, mostrando que a concorrência pode atrasar investimentos.
Until 1997 The Brazilian Electric Sector was basically a monopoly administrated by federal and state enterprises. In the second semester of 1997 it was begun privatizations and the restructuring process. Before Brazilian Electric Sector restructuring process, the planning of generation expansion was made through a centralized program which focus in minimize the investment and operation costs. The generation expansion was a decision variable of the problem. However, one of the assumptions of the restructuring sector process was and continues to be the private agent realization of a big share of the new investment in generation. So, the generation expansion is not more centralized, becoming a variable, which depends of the investment affordability of this agent. In this context, the present thesis studies the private investment dynamics in thermoelectric generation using Real Options. The dynamic of investment in thermal Plants will be studied in three different situations: In the first, it will be used a model of real options / decision analysis to determine the best timing of construction, considering that exists an exogenous uncertainty in the thermal supply expansion. In the second situation, the same model will be used to define the best timing of investment in thermal plants, considering that exists demand uncertainty, and that the supply expansion remains constant. In the third situation, the supply expansion occurs in response of the demand uncertainty evolution and the strategic interactions between the agents. It will be used a real options/ decision analysis/ game theory model. The main results obtained were the threshold contracted prices and the determination of the best time to invest as a function of some problem variables. It was possible to compare the different studied situations, showing that the competition could delay investments.
Yunus, Mamoon I. (Mamoon Iqbal). "Spatial- and time-dependent thermal and electrical behavior of quenching high-temperature superconducting composite tapes". Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/35046.
Pełny tekst źródła