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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Création et caractérisation d'un matériau de construction composite incorporant un nouveau matériau à changement de phase solide-solide / Creation and characterization of a building material with a new solid-solid phase change material

Harle, Thibault 14 November 2016
Dans le cadre de la réduction des consommations d'énergies primaires des bâtiments, de nouveaux matériaux de constructions sont amenés à être développés. Les réglementations thermiques poussent les nouvelles constructions à être économes en énergie. Elles doivent aussi être moins impactantes sur l'environnement tout en garantissant le confort des occupants.Dans ce travail est présenté le développement d'un nouveau matériau de construction composite intégrant un matériau à changement de phase (MCP).Les MCP sont capables d'échanger passivement de l'énergie thermique avec leur environnement. Il permettent ainsi une régulation passive de la température intérieure.Suite à un état de l'art, sur les MCP et le plâtre, est présenté la synthèse et la caractérisation physico-chimique d'un nouveau MCP à transition solide-solide.L'incorporation du MCP préalablement synthétisé à un matériau de construction de type plâtre est ensuite développée. Le matériau composite ainsi obtenu est caractérisé thermiquement et mécaniquement.Dans un dernier temps des évaluations environnementales du MCP et du matériau composite sont réalisées. / In a context of reduction of energy consumption in buildings, new buildings materials are developed. Thermal regulations require energy efficiency to buildings. They must be less impacting on the environment while ensuring occupant comfort.In this work is presented the development of a new composite building material incorporating a phase change material.PCM are able to exchange passively heat energy with their environment. It thus allow a passive control of the interior temperature of buildings.After a state of the art on PCM and plaster, a part is dedicated to synthesis and physicochemical characterisation of a new solid/solid PCM. In a third part the incorporation of the PCM previously synthesized in plaster is then developped. The composite material is mechanically and thermally characterized.In a last time environmental assessments of the PCM and the composite material are performed.
82

The Control of Surface Skin Temperature Through Hypnosis and Hypnotic Age Regression

Neuger, Gary Jay 12 1900 (has links)
A total of 60 male and female subjects scoring between 0-5 and 8-12 on the Harvard Group Scale of Hypnotic Susceptibility: Form A underwent hypnosis procedures, hypnosis and age regression procedures to age 10, or were read an article about hypnosis. All subjects then listened to 20 minutes of directed imagery for warming and cooling the hands. Skin temperature was monitored on both index fingers. Dependent measures were the difference between each subject's highest temperature and baseline temperature, the difference between each subject's baseline temperature and lowest temperature, and the latency of change from baseline to highest temperature, and the latency of change from the beginning of cooling imagery to lowest temperature. Results indicated that the age regression group achieved significantly warmer temperatures than the control group and that the age regression group remained significantly warmer than the two other groups during the cooling imagery. Results also indicated that these skin temperature responses generalized to the nondominant hand. The data were interpreted as suggesting that those subjects exposed to the age regression procedures may have been more relaxed than the other groups. Another interpretation suggested the cooling imagery may not have been accessing common or pleasant experiences of the subjects.
83

Temperature Biofeedback and Visual Imagery in the Treatment of Migraine Headaches

Clark, Susan Matthews 12 1900 (has links)
After an initial four week baseline period, during which headache activity and medication consumption were monitored, 28 migraineurs were randomly assigned to one of the following groups: (a) the biofeedback temperature warming group, (b) the visual imagery group, (c) the combined treatment group, or (d) the comparison group. All four groups continued to monitor their headache activity and medication consumption during the eight week treatment period and the eight week follow-up period. A two way analysis of variance computed on groups over time indicated a significant decrease in headache activity and medication consumption. During the follow-up period (a) the combined treatment group had significantly fewer headaches than the biofeedback group or the comparison group and (b) the visual imagery group and the combined treatment group had significantly fewer headache hours than the biofeedback group or the comparison group. These results do not appear to be attributable to differences between groups on the amount of time spent in home practice or subjective ratings of relaxation. There was no consistent relationship between increases in finger temperature and headache activity improvement. Decreases in powerful other scores, as measured by the Health Attribution Test, and increases in subjective ratings of internal control were consistent with a reduction in headache activity and medication consumption.
84

Mikroprocesorem řízený regulátor teploty / Microcontroller based temperature controller

Perůtka, Martin January 2008 (has links)
The aim of the work was to design and carry out a microprocessor driven temperature controller which will be operated by PC or immediately by its own control panel. The controller should serve, for example, as a regulation of temperatures in rooms, in ovens where electrical energy is used for heat production. This controller is able to measure temperature through connected temperature sensors, which means a thermistor PT1000 and a thermocouple type K, and to regulate temperature by the help of a heating body connected to the power output part of the controller.In this piece of work there is an issue of temperature measuring by the help of thermocouples and thermistors analysed, there are also mentioned the means of controlling and switching of alternating electrical tension for power operating and analysis of an issue of device connection and communication by the help of RS232 interface and USB with PC. The work also deals with a design of PSD controller with its subsequent realisation. The controller is tested on a micro-condensational siccative oven developed for the UTB research in Zlín.
85

The metabolic cost of behavioral thermoregulation of body temperature in the northern alligator lizard Gerrhonotus coeruleus, and how it affects the classical concept of eurythermality

Campbell, James Dudley 01 January 1981 (has links)
The effect of total metabolic cost expenditures on the precision of behavioral thermoregulation was investigated for the purportedly eurythermic Northern Alligator lizard (Gerrhonotus coeruleus). An operant apparatus was designed to test metabolic output at different heat reinforcement magnitudes. The mean TB reflected in each trial was positively correlated to the length of reinforcement. The shuttle rate during each trial was inversely correlated to the length of reinforcement. The standard deviation and total metabolic costs did not vary significantly between trials undertaken at the same ambient temperature. Eurythermality in G. coeruleus is caused by fluctuations in preferred body temperature and not by fluctuations around this temperature. The metabolic cost of behavioral thermoregulation did not change with corresponding changes in reinforcement magnitude. This indicates that eurythermality is the recorded effect of lizards behaviorally regulating to different TB in a stenothermic manner, rather than of random TB fluctuations in a wide range of normal activity (the classical view of eurythermality).
86

Effects of Temperature on Cherimoya Reproductive Organs / 温度がチェリモヤの生殖器官に及ぼす影響

Matsuda, Hiroshi 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19043号 / 農博第2121号 / 新制||農||1032(附属図書館) / 学位論文||H27||N4925(農学部図書室) / 31994 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 縄田 栄治, 教授 田中 千尋, 教授 北島 宣 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
87

Seasonal Thermal Acclimation in a Population of Iguanid Lizards (Sceloporous o. occidentalis, Baird and Girard, 1852)

Greene, Charles Stetson 01 January 1967 (has links) (PDF)
Within the few years following the publications of the first studies on reptilian thermoregulation (Mosauer, 1936; Attsatt, 1939; Cowles and Bogert, 1944; and Strelnidov, 1944) there has been an increasing number of investigations concerned with the mechanisms that underlie this phenomenon. Many studies have demonstrated that heliothermic lizards maintain a relatively constant body temperature during per- iods of diurnal and seasonal activity. Much of this regulation is dependent upon behavior. An extensive review of thermoregulation in both lizards and snakes has been compiled by St. Girons and St. Girona (1956).
88

Skin Temperature Control: A Comparison of Direct Instruction, Autogenic Suggestion, Relaxation, and Biofeedback Training

Vasilos, James G. 05 1900 (has links)
The purpose of this investigation was to separate the effects, and determine the optimal and most feasible methods, of promoting skin temperature increase in a clinical prison population. There were no significant differences among the instructional sets with respect to skin temperature increase. Skin Temperature feedback significantly delayed the time of maximum temperature increase. However, the average delay of 3.5 minutes was not considered to be clinically significant. No other significant effects were evidenced from feedback training. It was suggested that the lack of differential effects among the instructional sets and feedback training may be a characteristic of the early stages of training and that significant differences might emerge if training were continued over a greater number of sessions.The question was raised as to whether skin-temperature training had taken place during the two training sessions. The subjects may have been displaying a nonspecific "relaxation response" or habituation to the experimental situation. It may take more than two sessions before significant conditioning of the skin-temperature response occurs. Recommendations for future research were specified, including an increase in the number of training sessions and the addition of new control procedures.
89

RESPONSES OF BOYS AND MEN EXERCISING IN THE HEAT / BOYS AND MEN EXERCISING IN THE HEAT: THERMOREGULATION, DEHYDRATION AND PERFORMANCE, AND SUBSTRATE UTILIZATION

Tomedi Leites, Gabriela January 2016 (has links)
There is a common belief that children compared with adults are at a greater risk for exercise-induced heat illness. However, a limitation of previous studies involves different exercise intensities used in the comparison between children and adults. Dehydration impairs aerobic performance, but its effects on strength are not well understood. Sports drinks are often used as ergogenic aids. There is some evidence to suggest children have a greater reliance on exogenous carbohydrate compared to adults, which could require special considerations when children exercise in the heat. The overall purpose of this thesis was to compare physiological and metabolic responses during exercise in the heat between boys and men. Three studies were conducted to 1) compare the thermoregulatory responses of boys and men exercising in the heat at a fixed absolute metabolic heat production or a fixed metabolic heat production per unit of body mass; 2) compare the effects of 2% hypohydration or, euhydration with and without carbohydrate ingestion during exercise in the heat on subsequent strength in boys and men; and 3) examine the effects of exogenous carbohydrate on endogenous metabolism in boys and men exercising in the heat. Age and body size differences between boys and men did not influence thermoregulatory responses at a fixed metabolic heat production per unit of body mass. No differences in strength were observed among trials. When exercising in the heat, the relative contribution of ingested carbohydrate and endogenous substrate to total energy yield were not different between groups. These findings together have practical implications for boys and men who exercise in the heat. Specifically, moderate exercise in the heat is equally safe for boys and men. The effects of hypohydration and a carbohydrate drink compared to water on muscle strength performance following exercise in the heat are minimal. An important practical application is that carbohydrate intake spared endogenous fuels during exercise in the heat in both groups. / Thesis / Doctor of Philosophy (PhD) / Children may not adapt to temperature extremes as effectively as adults. Thermoregulatory differences may be due to variable exercise intensities prescribed in available child-adult comparisons. Dehydration affects aerobic performance, but its effects on strength are not well understood. Sports drinks are often used to offset dehydration and improve performance; however, the body may have a harder time using sugar drinks when exercising in the heat. The purpose of this thesis was to compare bodily responses of boys and men during exercise in the heat. Our findings have important practical implications for boys and men who exercise and play sports in hot temperatures. Specifically, exercise in the heat is equally safe for boys and men. The effects of hypohydration and a sports drink on muscle strength performance following exercise in the heat are minimal. Finally, although exercise in the heat may affect the use of a sugar drink, boys and men may use this drink to improve aerobic performance, while maintaining hydration levels.
90

Effects of opioid antagonism on thermoregulation during prolonged exercise in the heat

Hickey, Matthew Sean 11 June 2009 (has links)
Five adult male volunteers were studied to investigate the effect of opiate receptor blockade on the physiological response to a maximum of 60 minutes of stationary cycling at 70% V02peak in a hot (33 0 C/65% RH) environment. Exercise bouts were conducted following the administration of naloxone (4mg IV) 5 minutes prior to exercise with a follow-up 4mg dose at 25 minutes of exercise. In the placebo trial, volume-matched doses of saline were administered at the same points. No significant drug effect was observed on rectal or mean skin temperature during exercise. Post-exercise skin temperature was significantly (P<.001) higher on naloxone versus saline. Forearm blood flow (FBF) was consistently higher from minute 25 of exercise until test termination, although only the minute 25 and minute 55 data points were significantly elevated (P<.05, P<.005, respectively) . The rectal temperature threshold at which FBF plateaued was higher on naloxone (P=.054), and the FBF: rectal temperature slope was higher on naloxone throughout the trial. No significant changes were observed in heart rate or estimated mean arterial pressures, although both were consistently lower on naloxone. Gross sweat response was not altered by the drug. Plasma Beta-Endorphin was significantly (P<.Ol) higher on naloxone versus saline, and Beta-Endorphin was significantly elevated in the naloxone trial only. The observation that FBF was significantly higher on naloxone without inducing compensatory heart rate or blood pressure changes suggests that the opioids may be involved in the blood volume shifts that occur during prolonged exercise in the heat. / Master of Science

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