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Li, Li. "Differential infrared radiometer-based thermometric instrument for non-contact temperature and friction measurements." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58841.pdf.
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Fleming, Austin Drew. "Nonlinear Photothermal Radiometry and its Applications to Pyrometry and Thermal Property Measurements." DigitalCommons@USU, 2017. https://digitalcommons.usu.edu/etd/6545.
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Accurate temperature and thermal property measurements are critical for the modeling and prediction of heat transfer. In many industries thermal management is a limiting factor of performance, and rely on advanced modeling techniques to develop and design methods to better manage thermal energy. This study expands the thermal property and pyrometry measurement capabilities by developing three new techniques based on thermal emission’s nonlinear dependence on temperature.
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Mikula, Martin. "Termodiagnostika - dotykové a bezdotykové měření teploty." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231525.
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This thesis is concerned with thermodiagnostics in industrial practise, which is very important for the assessment of technical condition of object on the basis of temperature, in today's time. It includes summary of contact and contact-free methods and their principle, advantages and disadvantages for aplication in industrial practise. Because of thesis it was carried out measurement in company Daikin Device Czech republic with the use of contact thermometer and two available thermocameras for solving of topical tasks relating to production.
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Alshawaf, Hussain M. J. A. A. M. A. "A Novel Thermal Method for Pipe Flow Measurements Using a Non-invasive BTU Meter." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/101528.
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This work presents the development of a novel and non-invasive method that measures fluid flow rate and temperature in pipes. While current non-invasive flow meters are able to measure pipe flow rate, they cannot simultaneously measure the internal temperature of the fluid flow, which limits their widespread application. Moreover, devices that are able to determine flow temperature are primarily intrusive and require constant maintenance, which can shut down operation, resulting in downtime and economic loss. Consequently, non-invasive flow rate and temperature measurement systems are becoming increasingly attractive for a variety of operations, including for use in leak detection, energy metering, energy optimization, and oil and gas production, to name a few. In this work, a new solution method and parameter estimation scheme are developed and deployed to non-invasively determine fluid flow rate and temperature in a pipe. This new method is utilized in conjunction with a sensor-based apparatus--"namely, the Combined Heat Flux and Temperature Sensor (CHFT+), which employs simultaneous heat flux and temperature measurements for non-invasive thermal interrogation (NITI). In this work, the CHFT+ sensor embodiment is referred to as the British Thermal Unit (BTU) Meter. The fluid's flow rate and temperature are determined by estimating the fluid's convection heat transfer coefficient and the sensor-pipe thermal contact resistance. The new solution method and parameter estimation scheme were validated using both simulated and experimental data. The experimental data was validated for accuracy using a commercially available FR1118P10 Inline Flowmeter by Sotera Systems (Fort Wayne, IN) and a ThermaGate sensor by ThermaSENSE Corp. (Roanoke, VA). This study's experimental results displayed excellent agreement with values estimated from the aforementioned methods. Once tested in conjunction with the non-invasive BTU Meter, the proposed solution and parameter estimation scheme displayed an excellent level of validity and reliability in the results. Given the proposed BTU Meter's non-invasive design and experimental results, the developed solution and parameter estimation scheme shows promise for use in a variety of different residential, commercial, and industrial applications.MS
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Jordan, Jorge J. "UNDERSTANDING THE NON-CONTACT TEMPERATURE MEASUREMENT TECHNOLOGY." International Foundation for Telemetering, 2005. http://hdl.handle.net/10150/605042.
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ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, NevadaThe ability to accurately measure the temperature of different materials has always been a challenge for the Instrumentation Engineer. The use the classic contact type temperature detector such as thermocouples or RTD’s (Resistance Temperature Detectors) has not always shown to be the best approach to obtain the expected measurement. When not used carefully in closed environments, thermocouples and RTD’s could report the environmental temperature rather than the temperature from the product under examination. They are also temperature limited and when needed for applications above those limits, very expensive and low reliable materials are necessary to do the job. The use of non-contact thermometers has become the preferred choice for such applications. They have also come as a solution for the difficulties involved in the temperature measurements of moving targets. The industry has used portable and spot type infrared thermometers for some time, but the demand for better and more precise measurements has brought an incredible number of new products to the market. By means of advanced electronics and new software developments these products are used to cope with the difficulties of acquiring challenging measurements. Some of the same demands have made necessary the use of non-contact temperature measurement devices on aircraft instrumentation applications. The use of these capabilities has allowed the data acquisition community to get valuable data that was very difficult if not impossible to obtain before. In spite of all these facts, this promising emerging technology demands very careful attention before it is put to good use. The many products and solutions available do not accurately address every problem and the selection of the wrong technology for a specific task can prove to be fatal. The use of non-contact temperature devices is not an easy “off the shelf” pick but rather an option that demands knowledge of the infrared measurement theory as well as a complete understanding of the material under observation. The intention of this paper is to provide a practical understanding on the non-contact temperature measurement methods to the Aircraft Instrumentation Engineer who has not benefited from the use of this exiting technology.
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Weick, Brian L. "Infrared measurements of surface temperatures during oscillating/fretting contact with ceramics." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-03122009-040542/.
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Pollard, William Nichols Jr. "Non-contact Temperature Measurement of Stainless Steel in a TIG Welding Process." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/35433.
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The goal of this research was to design and test an experimental setup capable of performing a TIG welding process and acquiring temperature measurements near the weld with the use of an infrared spot sensor. The data collected can then be used to validate a computer simulation that models the exact same process. An experimental setup was built, and preliminary temperature data were collected. It was determined that infrared measurements taken at the arc contain excessive amounts of interfering radiation emanating from the welding zone. The optimal angle of orientation is normal to the weld line. In this way an infrared spot sensor can be focused on an area just down weld of the arc where the temperatures remain relatively high and thermal gradients, although still large, are at a minimum. Additional data were collected from thermocouples to validate the infrared sensor results and also to provide additional data that can be compared to a computer model. Sources of error were identified and recommendations were made as to how they can be avoided or minimized.Master of Science
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Edwards, Joseph Richard. "Equilibrium moisture content measurement for porous building materials at various temperatures." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-03042009-041243/.
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Burtzlaff, Andreas [Verfasser]. "Shot noise measurements at single atom contacts in a low-temperature scanning tunnelling microscope / Andreas Burtzlaff." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1136903283/34.
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Daubriac, Richard. "Caractérisation de techniques d'implantations ioniques alternatives pour l'optimisation du module source-drain de la technologie FDSOI 28nm." Thesis, Toulouse, INSA, 2018. http://www.theses.fr/2018ISAT0031/document.
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Durant ces dernières années, l’apparition de nouvelles architectures (FDSOI, FinFETs ou NW-FETs) et l’utilisation de nouveaux matériaux (notamment SiGe) ont permis de repousser les limites des performances des dispositifs MOS et de contourner l’effet canal court inhérent à la miniaturisation des composants. Cependant, pour toutes ces nouvelles architectures, la résistance de contact se dégrade au fil des nœuds technologiques. Celle-ci dépend fortement de deux paramètres physiques : la concentration de dopants actifs proches de la surface du semi-conducteur et de la hauteur de barrière Schottky du contact siliciuré. De multiples procédés avancés ont été proposé pour améliorer ces deux paramètres physiques (pré-amorphisation, recuit laser, ségrégation de dopants, etc…). Afin d’optimiser les conditions expérimentales de ces nouvelles techniques de fabrication, il est primordial de pouvoir caractériser avec fiabilité leur impact sur les deux grandeurs physiques citées. Dans le cadre de cette thèse, deux thématiques dédiées à l’étude de chacun des paramètres sont abordées, explicitant les méthodes de caractérisation développées ainsi que des exemples concrets d’applications. La première partie concerne l’étude de la concentration de dopants actifs proches de la surface du semi-conducteur. Dans cet axe, nous avons mis en place une méthode d’Effet Hall Différentiel (DHE). Cette technique combine gravures successives et mesures par effet Hall conventionnel afin d’obtenir le profil de concentration de dopants actifs en fonction de la profondeur. Nous avons développé et validé une méthode de gravure chimique et de mesure électrique pour des couches ultra-minces de SiGe et de Si dopées. Les profils de concentration générés ont une résolution en profondeur inférieure à 1 nm et ont permis d’étudier de façon approfondie dans les premiers nanomètres proches de la surface de couches fabriquées grâce à des techniques d’implantation et de recuit avancées comme par exemple, la croissance en phase solide activée par recuit laser. La deuxième partie porte sur la mesure de hauteurs de barrière Schottky pour des contacts siliciurés. Durant cette étude, nous avons transféré une technique se basant sur des diodes en tête bêche pour caractériser l’impact de la ségrégation de différentes espèces à l’interface siliciure/semi-conducteur sur la hauteur de barrière Schottky d’un contact en siliciure de platine. Cette méthode de mesure associée à des simulations physiques a permis d’une part, d’extrairer avec fiabilité des hauteurs de barrières avec une précision de 10meV et d’autre part, d’effectuer une sélection des meilleures conditions de ségrégation de dopants pour la réduction de la hauteur de barrière Schottky. Pour conclure, ce projet a rendu possible le développement de méthodes de caractérisation pour l’étude de matériaux utilisés en nanoélectronique. De plus, nous avons pu apporter des éclaircissements concernant l’impact de techniques d’implantation ionique alternatives sur des couches de Si et SiGe ultrafines, et ce, dans le but de réduire la résistance de contact entre siliciure et semi-conducteur dans le module source-drain de transistors ultimesDuring the past few decades, the emergence of new architectures (FDSOI, FinFETs or NW-FETs) and the use of new materials (like silicon/germanium alloys) allowed to go further in MOS devices scaling by solving short channel effect issues. However, new architectures suffer from contact resistance degradation with size reduction. This resistance strongly depends on two parameters: the active dopant concentration close to the semi-conductor surface and the Schottky barrier height of the silicide contact. Many solutions have been proposed to improve both of these physical parameters: pre-amorphisation, laser annealing, dopant segregation and others. In order to optimize the experimental conditions of these fabrication techniques, it is mandatory to measure precisely and reliably their impact on cited parameters.Within the scope of this thesis, two parts are dedicated to each lever of the contact resistance, each time precising the developed characterization method and concrete application studies. The first part concerns the study of the active dopant concentration close to the semi-conductor surface. In this axis, we developed a Differential Hall Effet method (DHE) which can provide accurate depth profiles of active dopant concentration combining successive etching processes and conventional Hall Effect measurements. To do so, we validated layer chemical etching and precise electrical characterization method for doped Si and SiGe. Obtained generated profiles have a sub-1nm resolution and allowed to scan the first few nanometers of layers fabricated by advanced ion implantation and annealing techniques, like solid-phase epitaxy regrowth activated by laser annealing. In the second part, we focused on the measurement of Schottky barrier height of platinum silicide contact. We transferred a characterization method based on back-to-back diodes structure to measure platinum silicide contacts with different dopant segregation conditions. The electrical measurements were then fitted with physical models to extract Schottky barrier height with a precision of about 10meV. This combination between measurements and simulations allowed to point out the best ion implantation and annealing conditions for Schottky barrier height reduction.To conclude, thanks to this project, we developed highly sensitive characterization methods for nanoelectronics application. Moreover, we brought several clarifications on the impact of alternative ion implantation and annealing processes on Si and SiGe ultra-thin layers in the perspective of contact resistance reduction in FDSOI source-drain module
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Seoudi, Tarek. "Non-intrusive CdSe-based quantum dots for sensing pressure and temperature in lubricated contacts." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI009.
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Cette thèse est dédiée à la mesure des pressions et des températures locales et à la comparaison de la génération de chaleur dans les contacts élastohydrodynamiques (EHD) de type tout acier et hybride (nitrure de silicium-acier). Le but ultime de ce travail est de développer une nouvelle technique in situ non-intrusive, exploitant la sensibilité de la photoluminescence (PL) des boîtes quantiques (QDs) de CdSe/CdS/ZnS aux variations de pression et température, afin de cartographier ces deux paramètres dans les contacts EHD. Dispersible à faible concentration dans les lubrifiants, il est montré que les QDs ne modifient pas le comportement rhéologique du fluide porteur et que le cisaillement n’est pas perturbateur à la réponse en PL. La calibration des QDs en suspension confirme la dépendance de la réponse en PL des QDs à la pression et à la température. Les mesures in situ sont effectuées en utilisant un banc d’essai bille-disque. La comparaison entre les mesures in situ de pression et de température et celles prédites à l'aide d'un modèle éléments finis TEHD interne montre une bonne concordance, ce qui démontre la faisabilité de la méthodologie proposée. Les effets du glissement et du chargement normal sur la pression, la température et la chaleur générée sont reportés. L’effet des propriétés thermiques des solides est souligné et la répartition de la chaleur générée entre les solides en contact est étudiée. L'équilibre énergétique entre l'énergie mécanique et l'énergie thermique interne générée par compression et cisaillement est démontré en comparant les pertes de puissance expérimentales et la chaleur générée issue du modèle numérique, pour des contacts acier-acier et hybridesThis thesis is dedicated to the measurement of local pressure and temperature and to compare the heat generation in all-steel and silicon nitride-steel (hybrid) elastohydrodynamic (EHD) contacts. The ultimate goal of this work is to develop a new non-intrusive in situ technique, exploiting the sensitivity of the photoluminescence (PL) of CdSe/CdS/ZnS quantum dots (QDs) to pressure and temperature. Dispersible in small concentration in lubricants, it is shown that the QDs doesn’t modify the rheological behavior of the carrier fluid and that shearing is not perturbative to the QDs PL response. The calibration of QDs in the suspension confirms the QDs PL dependence on temperature and pressure. The in situ measurements were conducted in EHD contacts using a ball-on-disc test rig. Comparisons between pressure and temperature measurements and predictions, using an in–house finite element thermal EHD model, showed a good agreement which demonstrates the feasibility of the proposed methodology. The effects of sliding and normal loading on pressure, temperature and heat generation are indicated. The effect of the thermal properties of the solid materials is underlined and the partition of the generated heat between the contacting solids is investigated. The energy equilibrium between the mechanical energy and the internal thermal energy generated by compression and shearing is demonstrated by comparing experimental power losses and numerical heat generation, in steel-steel and hybrid contacts
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Skotland, Christer Heen. "Measurement of temperature conditions in grate zone of a 1 MW wood-pellets boiler fired with high ash content wood-pellets." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-12885.
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The combustion of biomass could in some cases lead to ash problems induced by high temperatures such as ash sintering, agglomeration and melting. The degrees of these problems depend on the fuel feedstock and are highly dependent on the amount of potassium, sodium and chlorine in the biomass. Straw, grass, bark, branches and wood residues are typical examples of biomass fuels that are connected to the mentioned ash problems.Addition of additives in the problematic fuels is a possible measure in order to reduce the ash problems. This project studies the effect of some additives in a problematic wood pellet fuel and wheat straw. The wood pellet consist of residues from the furniture industry in the Møre area in Norway, and is causing ash problems in several boilers using this fuel. The additives, clay, sewage sludge, marble sludge and paper sludge, are added in 3 to 10 percent addition in the problematic fuels. The melting temperatures of the resulting ash, as well as the sintering tendency of the different fuel and additive mixtures, are analyzed.Melting experiments showed that the melting temperature of wood and straw ash was drastically increased by adding sewage and marble sludge. Clay was more effective for wheat straw than wood pellet. Paper sludge increased the melting temperature to some extent for straw ash, but not for wood pellet.The sintering test revealed an increased sintering for wood pellet with sewage sludge, and a much higher slagging tendency for clay. Marble sludge effectively decreased the sintering of wood pellet ash, even at 1200 °C. Paper sludge did neither reduce the sintering. All additives showed a positive effect on the wheat straw ash sintering, with marble sludge as the indisputable best additive.The wood pellet, and pellet together with 4 and 8 percent addition of sewage sludge, is combusted in a 1.2 MW boiler to investigate if the sewage are able to reduce the sintering and agglomeration of the ash. The combustion rounds showed that addition of sewage sludge drastically increased the amount of sintered and agglomerated ash. The form of the ash changed from hard slag to more porous ash, but the formed ash was still too hard to not cause problems with the ash removal system.
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Maignial, Isabelle. "Absorption et emission dans le domaine des ondes millimetriques de cavites resonnantes remplies de gaz, en vue d'effectuer des mesures sans contact de temperature et d'humidite." Toulouse 3, 1986. http://www.theses.fr/1986TOU30148.
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Le dispositif de mesure de l'humidite utilise une cavite resonnante ouverte traversee par le flux d'air etudie, et accordee a la frequence de 183 ghz. Le dispositif de mesure de la temperature comprend egalement une cavite ouverte, couplee a un radiometre qui fonctionne a 60ghz
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Aghili, Ali, and Haris Ribac. "Prediction of early age and time dependent deformations in a massive concrete structure." Thesis, KTH, Betongbyggnad, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231551.
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The heat development that occurs due to the hydration of cement is important to consider during casting of massive concrete structures. By using computer programs that are based on finite element methods (FEM), simulations can be performed on the heat- and strength development. In this project, a FE program called ConTeSt has been used in order to predict the temperature- and strain development in a massive concrete wall. If the potential risks in a concrete structure are evaluated before casting, economical savings, including a better casting plan could be obtained. The structure under investigation was a concrete wall behind one of the spillways in the hydro power dam of Storfinnforsen. Due to a re-construction of the wall, an opportunity occurred to develop a measurement plan of the casting and perform simulations on the wall. A sensitivity analysis was performed in order to investigate the effects on the temperature- and strain development, by varying the cement content, ambient temperature, wind speed and degree of restraint in translation. The results showed, that a higher cement content increased the rate of hydration and hence the temperature in the concrete. Higher wind speeds contributed to more cooling of the concrete which, in some cases, resulted in cracking due to contraction of the material. Cracking due to contraction also occurred when the ambient temperature was decreased. The ambient temperature did not have a significant impact on the rate of hydration, but instead the impact was larger from the initial temperature of the fresh concrete. A higher initial temperature of the fresh concrete increased the rate of hydration, which increased the temperature in the material. The degree of restraint could only be varied in translation in ConTeSt and hence the effect on the strain development was not that significant. A crack risk analysis was performed where the developed tensile stresses were compared with the tensile strength of the concrete. The same factors were varied as in the sensitivity analysis. The results showed that the tensile strength was exceeded for most of the cases and thus that the crack risk was high. The required equipment, in order to perform the measurements on site, consisted of 7 strain gauges of the module KM-100B from TML Tokyo Sokki Kenkyujo, 2 data loggers of the module Spider-8 from HBM, at least a 25 m ø9 mm 5-core shielded cable and a computer with the software Catman Easy.Värmeutvecklingen som uppstår på grund av hydratationen av cement är viktig att beakta vid gjutning av massiva betongkonstruktioner. Detta brukar göras genom simuleringar av värmeutvecklingen och hållfasthetstillväxten med hjälp av olika finita element (FE) program. I detta projekt har programmet ConTeSt använts för att på förhand kunna förutse temperatur - och töjningsutvecklingen i en massiv betongvägg. I och med detta kan bl.a. gjutningen planeras bättre samtidigt som ekonomiska besparingar kan åstadkommas om eventuella risker kan kartläggas innan gjutningen påbörjas. En ledmur bakom ett av utskoven i Storfinnforsens kraftverk undersöktes närmare i samband med en ombyggnad. Möjligheten uppstod att planera en mätning av gjutningen av ledmuren samt att utföra simuleringar av väggen i ConTeSt. En känslighetsanalys utfördes för att undersöka effekterna på temperatur- och töjningsutvecklingen genom att variera cementhalten, omgivningstemperaturen, vindhastigheten och graden av tvång i förskjutningen i längdriktningen av väggen. Resultaten visade att högre cementhalter ökade graden av hydratation vilket ökade temperaturen i betongen. Högre vindhastigheter bidrog till snabbare kylning av betongen vilket i vissa fall lett till sprickor på grund av kontraktion av materialet. Sprickor till följd av kontraktion uppstod även då omgivningstemperaturen sänktes. Omgivningstemperaturen hade ingen större påverkan på hydratationen, utan istället var det temperaturen av den färska betongmassan som visade större påverkan. Högre temperatur av den färska betongmassan ökade graden av hydratation vilket ökade temperaturen i betongen. Graden av tvång kunde i ConTeSt endast varieras i förskjutningen i längdriktningen av väggen vilket inte hade någon större effekt på töjningsutvecklingen. En sprickrisk analys utfördes där den utvecklade dragspänningen jämfördes med draghållfastheten. Analysen utfördes genom att variera samma faktorer som varierades i känslighetsanalysen. Resultaten visade att draghållfastheten överskreds i de flesta fall och att därmed sprickrisken var hög. För att genomföra mätningen blev slutsatsen att det behövs 7 st töjningsgivare av modell KM-100B från TML Tokyo Sokki Kenkyujo, 2 st data logger av typ Spider8 från HBM samt minst en 25 m ø9 mm skärmad 5-kärnkabel, inklusive en dator med programvaran Catman Easy.
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Kolářová, Dana. "Metody pro zpracování termovizních snímků s detekcí stanovené oblasti obličeje." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220853.
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This paper deals with non-contact measurement of temperature in human faces. Principle of measurement of infrared radiation and construction of the thermal imager is described in a literature search. The main part of the paper is design of an algorithm for automatic processing and the detection of regions of interest in thermal images. The theoretical description of used methods is also included in this paper. The aim is to design and implement a program for automatic evaluation of temperature changes in a human face in a sequence of thermal images that were taken with short time delay. As a part of thesis is description of implementation of designed algorithm in programming enviroment MATLAB and the description of the user interface. The program was tested on the experimental data samples. Obtained results and possible limitations are also discused in this paper.
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Hlubinka, David. "Teplotní vlastnosti automobilových zdrojů světla - Halogenové zdroje." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-318096.
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The aim of master´s thesis is to get acquainted with the design and materials used in selected automotive light source – tungsten halogen lamp. Further, the thesis focused on the theory and appropriate selection of the thermal measurement method on a real sample. Subsequently, a model of the light source and its simulation in the ANSYS – Maxwell 3D and Mechanical programs are created. Finally, the results of the thermal simulation and the non-contact measurement of the tungsten halogen lamp are evaluated
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Segalen, Christophe. "Complémentarité des propriétés électriques et rhéologiques pour une caractérisation des boues résiduaires." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22529/document.
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La gestion durable des boues résiduaires est l'un des grands enjeux du 21ème siècle. Si toutes les eaux usées produites par la population urbaine mondiale étaient traitées, ce qui est l’objectif ultime de l’OMS, 83 millions de tonnes de matières sèches seraient produites annuellement à l’horizon 2017. Pour réduire les coûts du traitement et de la valorisation des boues qui représentent la moitié de la facture de l’assainissement collectif, l’optimisation des procédés est nécessaire. Les ingénieurs ont donc besoin d’outils permettant d’adapter le fonctionnement des technologies de traitement aux caractéristiques des matériaux. Concrètement, les technologues ont besoin de connaître ou d’estimer le comportement en écoulement des boues, c’est-à-dire leurs propriétés rhéologiques, à chaque étape du traitement. Celles-ci ne pouvant être déterminées en continu, l’objectif de cette thèse est de démontrer la faisabilité d’utilisation des propriétés électriques pour prédire les écoulements des boues. Au cours de ce travail de thèse, les comportements rhéologique et électrique d’une boue type ont été établis : ainsi les propriétés d’écoulement d’une boue résiduaire peuvent être décrites par un modèle d’Herschel-Bulkley modifié (de façon à prendre en compte les cisaillements très élevés) tandis que sa signature électrique pourra être représentée par un circuit équivalent de Maxwell. L’impact de paramètres majeurs comme la température et la teneur en matières sèches sur les propriétés rhéologiques et électriques des boues et sur leur corrélation a été étudié. Les résultats obtenus nous ont également permis de montrer comment la structure du matériau est liée à ces caractéristiques. Enfin, des outils spécifiques ont été mis au point, pour la mesure simultanée des propriétés électriques et rhéologiques des fluides organiques complexes. L’ensemble des résultats obtenus ouvre de nombreuses perspectives, opérationnelles et fondamentalesSludge management is one of the 21st century’s main issues. If the whole wastewater produced by worldwide urban population was treated, which is the ultimate goal of WHO, 83 million tons of dry matter could be annually produced until 2017. In order to reduce the costs of sludge treatment and reuse, which represent half of the collective sanitation bill, process optimization is needed. Engineers are in need of tools allowing them to adapt treatment technologies to material characteristics. More specifically, technologists need to know or to estimate sludge flow behavior, i.e. their rheological properties, at each step of the process. However, these properties can’t be continuously acquired. The purpose of this thesis is then to demonstrate the feasibility of the usage of sludge electrical properties to predict their flow. During this work, rheological and electrical behavior of one sludge type had been established: so flow properties of sludge can be described by means of a modified Herschel-Bulkley model (so that high shear rates are taken into account), whereas electrical properties can be represented by Maxwell’s equivalent circuit. Major parameters impacts, as temperature and dry matter content on sludge rheological and electrical properties and their correlation have been studied. The results we obtained allowed us to highlight the way the structure of the material is related to these properties. Finally, specific tools have been developed for simultaneous measurement of rheological and electrical properties of complex organic fluids. All the obtained results open many operational and fundamental prospects
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Martinet, Baptiste. "Caractérisation thermomécanique et identification des endommagements d’un revêtement abradable de compresseurs basse et haute pression en condition de contact sévère." Electronic Thesis or Diss., Université de Lorraine, 2019. http://www.theses.fr/2019LORR0270.
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La réduction des jeux fonctionnels aubes/carter permet d’augmenter le rendement global d’un turboréacteur en limitant les fuites inter-étages. Cependant, les vibrations inhérentes au système ou l’ingestion de corps étrangers tend à produire des interactions aube/carter initiées en bout d’aube qui peuvent mener à la ruine du turboréacteur. L’utilisation de revêtements dits « abradables » permet de limiter la conséquence de ces interactions. En cas de contact avec les parties tournantes, le matériau abradable va « s’abrader » de façon préférentielle par rapport au bout d’aube en limitant les énergies d’interaction. Ces matériaux sont étudiés depuis de nombreuses années sur des bancs expérimentaux dans le but de développer des modèles numériques prédictifs. L’objectif de ces travaux de thèse est la caractérisation expérimentale de deux revêtements abradables du compresseur basse pression – l’AlSi-PE – et haute pression – le Metco 2043 – sur un banc expérimental existant. La configuration adoptée est simplifiée et se dédouane de la dynamique d’aube et du turboréacteur. La caractérisation thermomécanique des deux revêtements de l’étude a été rendue possible grâce à la corrélation des efforts d’interaction, des échauffements produits par le contact et des endommagements induits. Les développements technologiques ont permis de réaliser des essais représentatifs jusqu’à 135 m s−1 et 720 ◦C. Une modélisation semi-analytique basée sur la technique des fonctions de Green a également été mise en place pour estimer la température au contact et les coefficients de répartition du flux thermique dans l’aube et le revêtement abradable. Les résultats numériques ont finalement été corrélés à un essai pilote pour valider l’approcheReducing gaps between blades and the casing allows an increasing of the aircraft engines effi- ciency. Moreover, blade/casing interactions, mainly due to engine vibrations, may occur. They are localized at the blade tip and may lead to the engine failure. Specific materials called « abradable materials » are used to reduce interactions impact. When an interaction occurs, the abradable ma- terial will be worn preferentialy to the blade and limits the interaction energies. Those materials are studied since many years on experimental devices to develop predictive numerical models. The purpose of this thesis is the experimental characterization of two abradable materials grades from the low-pressure compressor – the AlSi-PE grade – and from the high-pressure compressor – the CoNiCrAlY-hBN grade – on an experimental device. The experimental configuration is simpli- fied and doesn’t take in account the blade’s and casing’s dynamic phenomena. Thermomechanical characterization of two coatings was performed thanks to the correlation between forces, tem- peratures and wear mechanisms. Technological developments allowed representative tests up to 135 m/s and 720 °C. Semi-analytical modeling with Green’s techniques has been used to predict friction temperatures and heat distribution coefficients in the blade and the abradable material. Results have been correlated to an experimental test to approve the model
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El, Bakali Abdelmagid. "Contribution à l’étude des échanges thermiques aux interfaces pour les procédés de formage à chaud : développement de moyens de mesure de l’émissivité et de la résistance thermique de contact (RTC) à haute température A fast and versatile method for spectral emissivity measurement at high temperatures." Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2020. http://www.theses.fr/2020EMAC0004.
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Les travaux présentés ici concernent les échanges de chaleur entre une tôle métallique et un moule en béton réfractaire ou en acier inoxydable sont abordés pour des températures comprises entre 600 et 1000°C, voire plus. Ces échanges sont décomposés en deux étapes : une phase d’approche sans contact dite radiative qui nécessite la détermination des propriétés radiatives des solides en présence puis une phase avec contact : détermination d’une Résistance Thermique de Contact (ou « RTC ») à haute température. Pour décrire ces deux étapes, deux nouveaux moyens expérimentaux ont été étudiés et développés :a) Un banc de mesure directe de l’émissivité à chaud a été développé afin d’étudier la phase sans contact. Une enceinte elliptique utilisant le principe d’un four à images a permis d’obtenir des températures élevées (jusqu’à 1250°C) ainsi que des vitesses de chauffe élevées (>11°C/s) sur les échantillons à caractériser. Une instrumentation permettant de réaliser des mesures d’émissivité spectrale et totale a également été développée. La méthodologie de mesure a été validée en choisissant le platine comme matériau de référence, de par sa bonne stabilité chimique, la faible dépendance de ses propriétés avec la température et des propriétés bien documentées. L’émissivité du TA6V et de l’Inconel 625 en fonction de la température ([600 ; 1000]°C) et du temps de chauffage (jusqu’à 5 heures) a ensuite été étudiée. b) Le développement d’un banc de mesure de la RTC à haute température a permis quant à lui d’étudier la phase avec contact. Ce moyen a pour objectif de mesurer la RTC entre des couples de matériaux métal/métal (TA6V ou Inconel 625 /Inox 310) ou métal/céramique (TA6V ou Inconel 625 /Béton réfractaire) pour des pressions allant jusqu’à 4MPa. L’approche adoptée a été de disposer une pastille métallique représentant la tôle (TA6V ou Inconel 625) entre deux barreaux représentant l’outil (Inox 310 ou béton réfractaire), eux-mêmes, amarrés à une machine de traction. Le chauffage a été réalisé en introduisant le barreau supérieur dans un four résistif porté à 1000°C maximum. L’instrumentation du barreau inférieur a permis de déterminer le flux de chaleur conductif traversant ainsi que sa température de surface, ce qui a permis de mesurer la RTC sur une gamme thermique comprise entre 450 et 800°C et une gamme de pression de contact comprise entre 0,1 et 4MPa. Les résultats obtenus à l’aide de ces deux bancs peuvent être intégrés dans des simulations numériques de formage, pour calculer des recettes de lampes. Ces valeurs ont conduit au formage réussi de de 4 tôles successives en TA6V avec de bonnes conformités géométriques et microstructuralesThe present work deals with the high temperature heat transfers involved in sheet/die contact within hot forming processes. The investigated heat ranges lie between 600°C and 1000°C while the study materials are namely TA6V and Inconel 625 (for the sheet) and AISI 310 stainless steel and refractory concrete (for the die). Under such industrial configuration, the heat transfers can be split in two steps: i) a gap closing phase during which the radiative property of the contact pair prevail and ii) a solid contact phase during which the conductive properties are involved and more precisely the thermal contact resistance (TCR). This twostep approach allows a separate investigation of both phenomena which are herein studied by the mean of two dedicated experimental means: a) The gap closing phase is studied through an emissivity measurement setup dedicated to high temperature. The chosen setup is inspired from elliptical oven setups. Its features include a heating rate over 11°C/s and a maximal in-service temperature of 1250°C. The related measurement instruments selection and design are also part of the presented work. The metrological aspects along with the uncertainty quantification are performed through the use of a reference material: pure platinum. This latter has proven worthy by its ability to sustain very high temperature while remaining free from oxidation. In addition, platinum’s optical properties are well documented throughout the scientific literature which provides solid comparisons with other published results. Finally, the construction of an emissivity database is presented for the two sheet materials of the study: TA6V and INCONEL 625. b) The solid contact phase is studied through a second tailor made experimental setup dedicated to TCR measurements. The proposed features include the ability to study metal contact pair (AISI 310 vs. TA6V/INCONEL 625) or ceramic vs. metal contact (Concrete vs. TA6V/INCONEL 625) for temperature as high as 800°C. The whole setup can be inserted within a classical tensile device in order to load the contact interfaces at stress levels similar to those involved in metal forming processes (here up to 4MPa). In practice, a circular sample cut from the studied sheet metals is clasped in between two cylindrical bars made of AISI 310 or concrete. The upper bar is then heated up by the mean of a resistive oven in order to generate a directional heat flux throughout the material interfaces. A suited measurement instrumentation then allows the assessment of the TRC for each contact pair for temperature ranging from 450°C to 800°C and pressure ranging from 0.1MPa to 4MPa. The results obtained from these two setups have built up a material database that was then use to simulate industrial hot forming operations. The process parameters retrieved from these simulation were used as input in an actual forming process and has led to the successful manufacturing of four parts all of which satisfying the quality requirements in term of geometry and microstructure
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Ančík, Zdeněk. "Modelování tepelných procesů letecké elektroniky a problematika jejího chlazení." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229169.
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This thesis is focus on thermal analysis of aircraft electronic devices and their cooling possibilities. The two analytic methods of thermal analysis are applied on two particular technical objects. The laboratory experiment of non-contact temperature measurement method is applied on real unit. The results of simulation are compared with results of experiment.
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Kruger, Ludi. "Distributed temperature sensing and non-contact torsion measurement with fibre bragg gratings." Thesis, 2009. http://hdl.handle.net/10210/2169.
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M.Ing.This thesis demonstrates the measurement of temperature distribution across a metal plate and the non-contact measurement of torsion in a rotating shaft. After a thorough theoretical study of the origin of fibre Bragg gratings, methods of fabrication and erasing of gratings, methods of demodulating the signals from gratings, and methods of discriminating between strain and temperature variations in gratings, simulations and experiments were done to prove the feasibility of both temperature distribution measurement and non-contact torsion measurement. For the measurement of temperature distribution, a 450 x 450 x 1.6 mm type 304 stainless steel plate was used. Two 4,7Ω 25W resistors were used as heat sources, and five fibre Bragg gratings measured the temperature at strategic points on the plate. The measured values were interpolated appropriately and a three-dimensional representation of the temperature distribution was shown on a personal computer monitor. The measurement of torsion was first done on a non-rotating 25 mm diameter solid shaft with torque applied. Both resistive strain gauges and fibre Bragg gratings were attached to the shaft and the measurement results compared well. Up to 90 Nm of torque was applied to the shaft. The non-contact measurement of torsion on a rotating shaft was done with fibre Bragg gratings and involved the use of graded index (GRIN) lenses for transmitting optical information between the light source, the gratings, and back to the spectrum analyser through free space. A special Böhler steel with high yield strength was used, and the set-up was mounted on a lathe. The one end of the shaft was clamped in the lathe chuck, and the other was fixed to an automobile drum brake system, allowing the application of torque on the rotating shaft. Up to 97 Nm of torque was applied to the shaft rotating at 190 rpm, and the results are within 10% of the expected values. As far as we are aware, this is the first time that torsion is measured by fibre Bragg gratings without the need to have physical contact with the shaft, i.e. slip rings, to transmit the information to and from the sensors. The experimental results of this thesis confirm that fibre Bragg grating sensors can be applied usefully in temperature distribution measurement, as well as in the measurement of torsional stress in rotating shafts.
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ZENG, WEN-DING, and 曾文丁. "The fast and reliable estimation of thermal contact conductance from transient temperature measurements." Thesis, 1989. http://ndltd.ncl.edu.tw/handle/23663610472938319282.
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Jain, Rajiv. "ECR Studies Across Bare And Gold Coated Metal Contacts At Low Temperatures." Thesis, 2009. http://hdl.handle.net/2005/1036.
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Electrical contact resistance (ECR) measurements are needed for judging the performance of electrical appliances. Understanding the behaviour of ECR at low temperature gives a unique opportunity for understanding the contact mechanism itself and controlling the contact resistance for its applications in various areas at these temperatures. In many high-end applications, sophisticated electronic devices are being operated below ambient temperature to improve their performance. The availability of cryogens, improvement in Thermo-Electrical (TE) based Peltier coolers, accelerated the development of these devices. In designing such systems, an accurate measurement of electrical contact resistance below room temperature is important.
A detailed experimental investigation has been conducted on electrical contact resistance across bare and coated metal contacts at low temperatures. As a part of the experimental investigation, a test facility capable of varying the contact force, surrounding pressure and temperature, is developed. The design, construction, testing and use of this facility are described. Electrical contact resistance at different contact pressures across copper, OFHC copper and brass with and without gold coatings is measured using 4-wire technique with high accuracy. The test specimen preparation, instrumentation and data acquisition are explained in detail. The setup is standardized by comparing the experimental results obtained across copper-copper contacts in vacuum with the theoretical model. The electrical contact resistance is measured as a function of contact force at different temperatures. The effect of loading and unloading, and the existence of hysteresis are experimentally studied. The electrical properties of conductors improve at low temperature but this is not true for contact resistance. At low temperature the contact resistance increases and it depends on applied contact force, hardness and roughness of the contacting surfaces. Gold-coated contacts exhibited an increase in contact resistance at low temperatures.
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Lee, Jonghyun. "Non-contact measurement of creep resistance of ultra-high-temperature materials." 2007. https://scholarworks.umass.edu/dissertations/AAI3254917.
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Continuing pressures for higher performance and efficiency in energy conversion and propulsion systems are driving ever more demanding needs for new materials which can survive high stresses at the elevated temperatures. In such severe environments, the characterization of creep properties becomes indispensable. Conventional techniques for the measurement of creep are limited to about 1,700°C. A new method which can be applied at temperatures higher than 2,000°C is strongly demanded. This research presents a non-contact method for the measurements of creep resistance of ultra-high-temperature materials. Using the electrostatic levitation (ESL) facility at NASA MSFC, a spherical sample was rotated quickly enough to cause creep deformation due to the centripetal acceleration. The deformation of the sample was captured with a digital camera, and the images were then analyzed to measure creep deformation and to estimate the stress exponent in the constitutive equation of the power-law creep. To compare experimental results, numerical and analytical analyses on creep deformation of a rotating sphere have been conducted. The experimental, numerical, and analytical results showed a good agreement with one another.
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Lu, Ming-Hung, and 呂明紘. "An Image-Based Non-Contact Pulse Rate and Body Temperature Measurement System." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/827u73.
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碩士國立臺灣科技大學
電子工程系
107
Vital Signs are signs that appear when maintaining the body's basic physiological functions. These measurements can be used to assess an individual's physical health, and in which the pulse rate and body temperature are the indicators most commonly used by doctors to monitor a patient's physical condition. Therefore, when visiting a doctor, patients are often asked to measure the pulse rate and body temperature first and the doctor will infer the conditions and prescribe according to the patient’s physiological values and the described symptoms. Today hospitals usually adopt contact instruments for measuring the pulse rate and body temperature. Yet the patients’ activities are limited during the process of measuring, and there is a risk of contact infection by using contact instruments in the hospital. To solve the above problems, this paper establishes an image-based contactless pulse rate and body temperature measurement system. This system can instantly perform contactless measurements by using a normal RGB camera and a far-infrared photo thermal image camera, which allows the users to move freely while measuring the pulse rate and body temperature. Thus not only can the risk of contact infection be avoided but the patients are given bigger activity space. However, according to previous research, contactless pulse rate signals are easily influenced by moving artifacts. This paper proposed an algorithm to reduce moving noise. Compared to previous research, the algorithm can measure the pulse rate more precisely in a state of severe shaking. According to the experimental results, the mean absolute error (MAE) and root mean square error (RMSE) are respectively 4.42 BPM and 6.21 BPM in a state where the user is shaking vigorously. In body temperature measurement, the paper proposed a new algorithm on human face temperature measurement that can automatically detect and track human face positions with a thermal image camera. In this way, the user can move freely and use the system more comfortably. According to the final experimental results, the MAE and RMSE of the measured body temperature were 0.375 °C and 0.439 °C, respectively.
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Qi, Hong Sheng, and Andrew J. Day. "Investigation of disc/pad interface temperatures in friction braking." 2007. http://hdl.handle.net/10454/2277.
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Qi, Hong Sheng, and Andrew J. Day. "Investigation of Disc/Pad Interface Temperatures in Friction Braking." 2006. http://hdl.handle.net/10454/7974.
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yesMaintaining appropriate levels of disc-pad interface temperature is critical for the overall operating effectiveness of disc brakes and implicitly the safety of the vehicle. Measurement and prediction of the distribution and magnitude of brake friction interface temperatures are difficult. A thermocouple method with an exposed hot junction configuration is used for interface temperature measurement in this study. Factors influencing the magnitude and distribution of interface temperature are discussed. It is found that there is a strong correlation between the contact area ratio and the interface maximum temperature. Using a designed experiment approach, the factors affecting the interface temperature, including the number of braking applications, sliding speed, braking load and type of friction material were studied. It was found that the number of braking applications affects the interface temperature the most. The real contact area between the disc and pad, i.e. pad regions where the bulk of the kinetic energy is dissipated via friction, has significant effect on the braking interface temperature. For understanding the effect of real contact area on local interface temperatures and friction coefficient, Finite Element Analysis (FEA) is conducted. It is found that the maximum temperature at the friction interface does not increase linearly with decreasing contact area ratio. This finding is potentially significant in optimising the design and formulation of friction materials for stable friction and wear performance.
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Mtangi, Wilbert. "Electrical characterization of ZnO and metal ZnO contacts." Diss., 2010. http://hdl.handle.net/2263/28131.
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The electrical properties of ZnO and contacts to ZnO have been investigated using different techniques. Temperature dependent Hall (TDH) effect measurements have been used to characterize the as-received melt grown ZnO samples in the 20 – 330 K temperature range. The effect of argon annealing on hydrogen peroxide treated ZnO samples has been investigated in the 200 – 800oC temperature range by the TDH effect measurement technique. The experimental data has been analysed by fitting a theoretical model written in Matlab to the data. Donor concentrations and acceptor concentrations together with the associated energy levels have been extracted by fitting the models to the experimentally obtained carrier concentration data by assuming a multi-donor and single charged acceptor in solving the charge balance equation. TDH measurements have revealed the dominance of surface conduction in melt grown ZnO in the 20 – 40 K temperature range. Surface conduction effects have proved to increase with the increase in annealing temperature. Surface donor volume concentrations have been determined in the 200 – 800oC by use of theory developed by D. C. Look. Good rectifying Schottky contacts have been fabricated on ZnO after treating the samples with boiling hydrogen peroxide. Electrical properties of these Schottky contacts have been investigated using current-voltage (IV) and capacitance-voltage (CV) measurements in the 60 – 300 K temperature range. The Schottky contacts have revealed the dominance of predominantly thermionic emission at room temperature and the existence of other current transport mechanisms at temperatures below room temperature. Polarity effects on the Schottky contacts deposited on the O-polar and Zn-polar faces of ZnO have been demonstrated by the IV technique on the Pd and Au Schottky contacts at room temperature. Results obtained indicate a strong dependence of the Schottky contact quality on the polarity of the samples at room temperature. The quality of the Schottky contacts have also indicated their dependence on the type of metal used with the Pd producing contacts with the better quality as compared to the Au. Schottky barrier heights determined using temperature dependent IV measurements have been observed to increase with increasing temperature and this has been explained as an effect of barrier inhomogeneities, while the ones obtained from CV measurements have proved to follow the negative temperature coefficient of the II – VI semiconductor material, i.e. a decrease in barrier height with increasing temperature. However, the values have proved to be larger than the energy gap of ZnO, an effect that has been explained as caused by an inversion layer. CopyrightDissertation (MSc)--University of Pretoria, 2010.
Physics
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Ko, Yung-Long, and 柯雲龍. "Thin-film Thermocouple Fabricated by Sputtering Deposition in Application to Contacted Temperature Measurement during Ultrasonic Wire Bounding." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/88009959160687123622.
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碩士國立中正大學
機械系
88
Wire bonding, mainly responsible for electricity and signal delivery among devices, is a critical process in electronic package. Depending on the materials to be connected, the three often-used boding techniques are the thermocompression, ultrasonic, and thermosonic wire bondings. Although these techniques have been used for years, the detailed bonding mechanism is still unclear. Some researchers believed that the boding is due to re-solidification of melting that is induced by heat generation from friction caused by the fast relative motion between wire and metal surface. Others, however, thought the metallic bonding was formed due to free electrons exchanged during fast friction process and no melting occurred. So far no direct experimental evidence is obtainable for the bonding mechanism. The time history of contact temperature is a good indicator for this understanding. During the bonding process, if the contact temperature was higher than the melting temperature, the melting and re-solidification should be a reasonable mechanism. Otherwise, the mechanism could be the latter. From the literature, the available experimental study showed that the contact surface temperature was about 80oC. This low temperature might be due to using an oversized and insensible temperature sensor. In the present study a thin-film, K-type thermocouple, 80m in width, fabricated by sputtering deposition is used to measure the transient temperature during the bonding process. Result shows that the contact temperature was up to 170oC. Thus it is reasonable to conjecture that contact temperature can be even higher if a more smaller temperature sensor is used.
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Shipp, Nicholas Jon. "The impact of core temperature corrections on exercise-induced hypoxemia." 2008. http://hdl.handle.net/2440/47970.
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The primary purpose of this doctoral dissertation was to investigate the effect of body temperature responses at physiologically relevant sites during an incremental exercise test on the phenomenon of exercise-induced hypoxemia (EIH). This phenomenon has been considered as an important limitation to physical performance with a prevalence of ~50 % in trained male athletes, but described in both sexes, across the range of both age and physical fitness in more recent literature. Previously this phenomenon has been described as a decrement in both arterial oxygen partial pressure (PaO₂) and oxy-haemoglobin saturation (SaO₂or SpO₂) with, particularly important for PaO₂, a lack of or inappropriate correction made for the change in body temperature during intense exercise. The initial study of this thesis determined the thermal response within the body at physiologically relevant sites measured simultaneously during an incremental exercise test. The results demonstrated the inadequacy of rectal temperature as an indicator of the acute temperature changes occurring during an incremental exercise test due to its slow response rate and relative thermal inertia. Radial arterial blood and oesophageal temperatures were shown to behave almost identically during the exercise test, albeit with an offset of approximately 1.3ºC, and were considered much more appropriate and relevant indicators of thermal changes during exercise. As an extension of the initial work active muscle temperature (vastus lateralis) was measured during the exercise test, demonstrating a significantly lower resting temperature than the oft-reported “core” temperatures (rectal and oesophageal) as well as a significantly greater increase in temperature in comparison to all other measurement sites. Overall, the results of this first study indicated that the physiologically relevant temperatures measured at the oesophageal and muscle sites differed markedly to the outdated rectal temperature measurement site and should be used as measures of thermal response when evaluating oxygen loading (oesophageal) or unloading (active muscle). Utilising the definition of EIH as a decrease in PaO₂ of ≥ 10 mmHg, the effect of temperature correcting PaO₂ was evaluated in the second study. Arterial blood gases measured simultaneously to the temperature measurements during the incremental exercise test were adjusted for the temperature changes at each site (every 1ºC increase in temperature will increase a PaO₂ value by ~5 mmHg). Whilst uncorrected PaO₂ values indicated an almost 100% prevalence of EIH in this group, oesophageal temperature corrected PaO₂ values decreased this prevalence to ~50% while muscle temperature corrections resolved all cases of EIH and demonstrated an HYPEROXAEMIA (i.e. the reverse of the well-established phenomenon) in the majority of subjects. Further investigation of arterial oxygen content during the exercise test indicates that there is no disruption in the delivery of oxygen to the active muscles and therefore any performance decrement should be attributed to another mechanism. Whilst the phenomenon of EIH is determined by the definition applied and the use of temperature corrections in the case of PaO₂, its reproducibility in a test-retest situation had not previously been determined. Utilising a subset of previously tested subjects, the reproducibility of both temperature and PaO₂ were determined with results indicating that the blood gas response was highly reproducible, especially the minimum PaO₂ value noted during each exercise test. However, comparing a more statistically relevant definition of a change in PaO₂ of ± 2 standard deviations from the mean resting PaO₂ to the previous delimiter of 10 mmHg indicated a lesser reproducibility of the prevalence of EIH. In summary, this thesis exposes the inadequacies of previous research into EIH with regard to the expected reproducibility of the phenomenon and the need to correctly adjust PaO₂ values for exercise-induce hyperthermia as well as demonstrating the difference in thermal responses to acute exercise in physiologically significant areas of the body. Furthermore, previously described correlations between the change in PaO₂ and VO₂ max were not evident in the subjects tested within this thesis, nor was there any indication of a diffusion limitation based on reduced pulmonary capillary transit time (by association with VO₂ max) or pulmonary oedema (rebuked by a rapid return of PaO₂ to above resting levels following exercise cessation).http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1320633
Thesis (Ph.D.) -- University of Adelaide, School of Medicine, 2008