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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.
141

ADVANCED AIRBORNE TEST INSTRUMENTATION SYSTEM (AATIS) PROGRAM SYSTEM OVERVIEW

Chang, Dah W. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Advanced Airborne Test Instrumentation System (AATIS), one of the major instrumentation systems in use today by the Department of Defense (DoD), was developed in the late 1980's to improve and modernize its predecessor - the Airborne Test Instrumentation System (ATIS). Use of AATIS, by not only the Air Force but the Navy and Army, has improved instrumentation commonality and interoperability across multiple test programs. AATIS, developed by the same manufacturer as the DoD Common Airborne Instrumentation System (CAIS), has a common bus structure - enabling cross utilization of many components which will ease transition from one system to another. The objective of this paper is to provide an overview on the Advanced ATIS System and its logistics support concept. For system description, an overview is presented on the airborne system and related ground support equipment. A brief description is given on the three levels of maintenance being used or planned for by the using activities. Finally, a projection is presented on the utilization of this system for the next 3 years.
142

Mediated learning in the rat : implications for perceptual learning

Leonard, Sarah January 1998 (has links)
No description available.
143

Role of the perifornical region of the lateral hypothalamus in appetitive conditioning

Morutto, Sara Lidia January 1999 (has links)
No description available.
144

Suitability of solar drive absorption cycle cooling for Kuwait

Al-Fahed, B. S. January 1985 (has links)
No description available.
145

Thermal mass enhancement for energy saving in UK offices

Whiffen, Thomas Richard January 2016 (has links)
Energy use in buildings accounts for more than a third of global energy demand, with humans seeking to create comfortable internal environments year-round. In the UK, air or water active thermal mass systems have demonstrated viability at delivering energy efficient comfort to office spaces. Whilst an attractive proposition, there are limitations to the cooling capacity and dynamic thermal response, giving rise to overheating in poorly designed buildings. The thesis work presented documents the investigation into active thermal mass enhancement to a prototype ventilated hollow core sample. Through engineering modelling (CFD, Excel VBA and IES) and laboratory (DSC, component and thermal chamber) testing two solutions were tested (an active-PCM module suitable for retrofit and embedded cool water pipes), with results conveying a 1 to 3°C temperature reduction and 0.1 to 0.2 kWh/m2/day AC savings during summer conditions. COP figures up to 10.6 were achieved through temperature set-point controlled water and air activated thermal mass. Economic analysis was conducted with positive results with the active-PCM module becoming viable for the UK’s non-domestic ‘Green Deal’ at a price point of approximately £300 per module. Following the laboratory led, and simulation supported work it was possible to conclude that active thermal mass enhancements can provide financially-viable energy-efficient, thermal-comfort for non-domestic UK properties. However the extent of the benefit depends heavily on the building thermal demands, available technology and optimised system control. Further work should be conducted to; develop additional modelling tools, underpinned by the laboratory data generated, and optimise the novel active-PCM technology, suitable for lucrative target markets.
146

Development and performance investigation on solar-powered thermoelectric radiant cooling in building-integrated system for a bedroom under hot and humid climate

Jarumongkonsak, Pornput January 2016 (has links)
In order to replace a conventional air-conditioner (AC) based on vapour compression technology that directly has high global warming potential and also currently consumes the most fossil fuel primary energy in building sector of tropical countries for generating thermal comfort on sleeping purpose, other alternative green space cooling technologies, as thermoelectric cooling (TEC), has to be improved to have same performance with AC. This research aims to develop and investigate a performance of Solar-powered Thermoelectric Radiant Cooling (STRC) system, as the combination of TEC and radiant cooling (RC) that is well known in its low energy consumption advantage. The studies were conducted through calculations, CFD simulations, system performance simulations and experiments. The results of optimum STRC system design was proved to provide better thermal and air quality performances, while the result in energy performance was depended on the TEC’s COP and vapour condensation prevention. After novel developing of TEC’s cooling channel with combined helical and an oblique fin to induce effective secondary flows that highly reduced the TEC’s hot side temperature in this research, the COP was able to increase up to 175%. Meanwhile, a novel bio-inspired combined superhydrophobic and hydrophobic coating on RC panel were able to competently repel most condensed water droplets, leaving just tiny droplets that was hard to be seen by naked eye. Finally, the COP of STRC system from house model experiment in 1:100 scales under hot and high humid climate was as high as 2.1 that helped STRC to consume electricity 34% less than AC system. Along with other benefits, as no working fluid, noise-free and low maintenance needs, the return of investment (ROI) was studied to be only 5-6 years when being operated with grid electricity and 17-18 years with PV panel generated electricity.
147

Startle eye-blink reflex as an index of emotion regulation in high and low monitors

Nelson, Jakob James, Filion, Diane L. January 2005 (has links)
Thesis (Ph. D.)--Dept. of Psychology. University of Missouri--Kansas City, 2005. / "A dissertation in psychology." Advisor: Diane L. Filion. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed March 12, 2007. Includes bibliographical references (leaves 115-120). Online version of the print edition.
148

An investigation of effects of flow conditioning on straight tube Coriolis meter

Shukla, Shashank 15 May 2009 (has links)
Coriolis meter, despite being very accurate in single phase conditions, fails to accurately measure two-phase flows. It poses a complex fluid-structure interaction problem in case of two-phase operation; there is a scarcity of theoretical models available to predict the errors reported by Coriolis meter in aforementioned conditions, hence the need for experimental research. Experiments are conducted in both single and two-phase flow conditions. Meter accuracy is excellent in single phase conditions and no significant effect is observed on use of flow conditioners, namely inlet swirl and inline mixer. Operational two-phase envelope is determined through experiments at different flowrates. Flow conditioners are used to study the effect of phase segregation and homogenization on accuracy of the meter. Testing is done to cover two-phase flows from both extreme ends, namely aerated liquids and wet gas. Use of flow conditioners show slight improvement in meter accuracy on use of inline mixer, and reduction in accuracy in case of inlet swirl, when both former and latter are compared to results obtained from experiments with no flow conditioners. The difference in accuracies between results with flow conditioner and without flow conditioners is attributed to relative motion between the phases, which is more in case of inlet swirl, due to larger bubble sizes. Flow conditioners show an insignificant effect on meter accuracy during wet gas tests. The reason proposed is annular flow regime, which is not highly affected by flow conditioners. Single phase tests demonstrate that Coriolis meter gives accurate measurement even in presence of severe flow disturbances. There is no need for flow conditioning before the meter to obtain accurate readings from it, which would be the case in other metering technologies like orifice and turbine. In two phase flows, the meter reports negative errors, which is consistent with previous experimental works available in literature. Use of flow conditioners clearly affects the reading of the meter in aerated liquids. This phenomenon can be used to get fairly accurate estimate of flow rate in low gas volume fraction liquid flows.
149

An investigation of effects of flow conditioning on straight tube Coriolis meter

Shukla, Shashank 15 May 2009 (has links)
Coriolis meter, despite being very accurate in single phase conditions, fails to accurately measure two-phase flows. It poses a complex fluid-structure interaction problem in case of two-phase operation; there is a scarcity of theoretical models available to predict the errors reported by Coriolis meter in aforementioned conditions, hence the need for experimental research. Experiments are conducted in both single and two-phase flow conditions. Meter accuracy is excellent in single phase conditions and no significant effect is observed on use of flow conditioners, namely inlet swirl and inline mixer. Operational two-phase envelope is determined through experiments at different flowrates. Flow conditioners are used to study the effect of phase segregation and homogenization on accuracy of the meter. Testing is done to cover two-phase flows from both extreme ends, namely aerated liquids and wet gas. Use of flow conditioners show slight improvement in meter accuracy on use of inline mixer, and reduction in accuracy in case of inlet swirl, when both former and latter are compared to results obtained from experiments with no flow conditioners. The difference in accuracies between results with flow conditioner and without flow conditioners is attributed to relative motion between the phases, which is more in case of inlet swirl, due to larger bubble sizes. Flow conditioners show an insignificant effect on meter accuracy during wet gas tests. The reason proposed is annular flow regime, which is not highly affected by flow conditioners. Single phase tests demonstrate that Coriolis meter gives accurate measurement even in presence of severe flow disturbances. There is no need for flow conditioning before the meter to obtain accurate readings from it, which would be the case in other metering technologies like orifice and turbine. In two phase flows, the meter reports negative errors, which is consistent with previous experimental works available in literature. Use of flow conditioners clearly affects the reading of the meter in aerated liquids. This phenomenon can be used to get fairly accurate estimate of flow rate in low gas volume fraction liquid flows.
150

Environmental, coat and health benefits of district cooling /

To, Ka-wing. January 2002 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2002. / Includes bibliographical references.

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