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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.
41

Implementation and appraisal of an in-fibre Bragg grating quasi-distributed health and usage monitoring system with applications to advanced materials

O'Dwyer, Martin Joseph January 2000 (has links)
No description available.
42

Aspects of fitness and physical activity patterns in Edinburgh school children

Blackwood, Susan Kim January 1997 (has links)
There is growing concern that many children in Britain do not take sufficient exercise to benefit cardiovascular health. This is supported by extensive evidence advocating the importance of regular physical activity for lifelong health and well-being, and is of particular relevance in Scotland given it's notorious record of adult coronary heart disease death. This study examined aspects of fitness and physical activity in groups of Edinburgh school children, aged between 13 and 14 years. A three stage investigation was adopted: Phase One: A repeated measures, same subject design was used to examine the reliability and validity of selected measures (20m shuttle run test, peak oxygen uptake (V02 Peak), and anthropometric measures). Thirty three children (15 boys, 18 girls) performed each test on 3 separate days. Anthropometric measures showed strong reliability (r > 0.94, n=33) whilst reliability for the treadmill test ofV02 peak and shuttle run performance was lower (r=0.89 and r=0.79 respectively). Multiple regression analysis yielded a new equation for predicting V02 peak for children. This age specific prediction equation incorporated shuttle run performance in conjunction with skinfold thickness measures (Boys, R2=0.64 SEE=3.46; Girls, R2=0.79, SEE=2.81). Repeat testing was also recommended. Phase Two: An evaluation of methods of heart rate data analysis to assess physical activity in children. Twenty eight children (14 boys, 14 girls) wore continuous heart rate monitors (polar Electro PE4000, Finland) over a period of 7 days (Monday to Sunday), mean duration 737 (+/-55) mins/day. A detailed 7 day self report activity diary was also completed. Variability of heart rate measures was high (R=0.10-0.30), and it was noted that using data for just 4 days or less resulted in considerable underestimation of total weekly activity levels (44-100% error). If activity levels are to be compared against current recommendations, researchers must endeavour to achieve weekly rather than daily estimates of activity. Evaluation of methods of heart rate data analysis showed good correlation between heart rate activity indices and reported seven day activity. For boys strongest correlation was achieved using the number of 5 minute periods with HR > 139 b.min"l and the number of 5 minute periods with HR > 50% heart rate reserve (r=0.80, n=14). Total activity time was similar for both males and females but girls engaged in fewer sustained bouts of activity (>5 minutes) and a better correlate with activity in females was achieved using the total number of elevated heart rates (total HR > 50% heart rate reserve, r=0.64, n=14). Phase Three: A cross sectional survey was conducted to investigate standards of aerobic fitness and patterns of physical activity in groups of Edinburgh school children. Height, weight, skinfold thickness, shuttle run performance and physical activity (assessed by heart rate monitoring and activity diary) were recorded in a sample of 91 children (44 Boys, 47 Girls). Overall, males performed significantly better on the shuttle run test (t=5.4, df=88, p < 0.05), had higher predicted peak oxygen uptake (t=5.6, df=87, p < 0.05), and engaged in more bouts of moderate to vigorous activity than females. Seventy percent of boys and 50% of girls fulfilled current physical activity guidelines. Most activities were school based (131 mins per week as compared to 85 mins per week of out of school activities). Activity tended to be sporadic with active days interspersed with inactive days (mean 3.2 +/·1.6 days per week). After school activities specifically targeting young girls should be promoted.
43

Origin of the Tower Peak unit in the St. Cyr area, Yukon, Canadian Cordillera

Isard, Sierra Juliane 01 May 2014 (has links)
The Yukon-Tanana terrane (YTT) is a composite arc built on the rifted margin of western North America. The YTT is present in the southeastern part of the St. Cyr area in south-central Yukon, but in the northwest section the structural and lithologic relationships are poorly known. This study describes the structural geometry of the northwest section of the St. Cyr area, west of the Canol Road. The lithological, geochemical, and geochronological characteristics of the Tower Peak unit are investigated in an effort to determine its origin and terrane affinity. In the study area, the Tower Peak unit sits tectonically above a low-grade mafic-ultramafic unit. In turn, this mafic-ultramafic unit is thrust over phyllite and marble creating a composite klippe. Detrital zircons from the marble indicate a maximum depositional age of 368 Ma. This result is consistent with the footwall being part of the Devonian to Mississippian Finlayson assemblage, the oldest arc of the composite YTT. The Tower Peak unit is a massive but fractured, sub-greenschist facies metabasalt. Whole-rock and trace element geochemistry of four Tower Peak samples suggest an oceanic or island arc setting for deposition of the Tower Peak unit. Zircons separated from three samples of the Tower Peak unit give a range of U-Pb ion probe ages. Three distinct age populations exist: 600-2582 Ma, 433-303 Ma, and 140-190 Ma. The preferred interpretation is that the Tower Peak unit is Mesozoic in age and may derive from Stikinia or Quesnellia.
44

On the Timing of the Peak Mean and Variance for the Number of Customers in an M(t)/M(t)/1 Queueing System

Malone, Kerry M., Ingolfsson, Armann 07 1900 (has links)
This paper examines the time lag between the peak in the arrival rate and the peaks in the mean and variance for the number of customers in an M(t)/M(t)/1l system. We establish a necessary condition for the time at which the peak in the mean is achieved. In cases in which system utilization exceeds one during some period, we show that the peak in the mean occurs after the end of this period. / Revised October 1994
45

Peak Population: Timing and Influences of Peak Energy on the World and the United States

Warner, Kevin 1987- 14 March 2013 (has links)
Peak energy is the notion that the world’s total production of usable energy will reach a maximum value and then begin an inexorable decline. Ninety-two percent of the world’s energy is currently derived from the non-renewable sources (oil, coal, natural gas and nuclear). As each of these non-renewable sources individually peaks in production, we can see total energy production peak. The human population is tightly correlated with global energy production, as agriculture and material possessions are energy intensive. It follows that peak energy should have a significant effect on world population. Using a set of mathematical models, including M King Hubbert’s oil peak mathematics, we prepared three models. The first approached the peak energy and population problem from the point of view of a “black-box” homogeneous world. The second model divides the world into ten major regions to study the global heterogeneity of the peak energy and population question. Both of these models include various scenarios for how the world population will develop based on available energy and per capita consumption of that energy. The third model examines energy and climate change within the forty-eight contiguous American states in order to identify some of the “best” and some of the “worst” states in which to live in the year 2050. The black box model indicates that peak energy will occur in 2026 at a maximum production of 104.1 billion barrels of oil equivalent (BBOE). Total energy production in 2011 was 92.78 BBOE. Three scenarios of different energy consumption rates suggest a peak world population occurring between 2026 and 2036, at 7.6-8.3 billion. The regional model indicates that even as each region protects its own energy resources, most of the world will reach peak energy by 2030, and world populations peak between 7.5 and 9 billion. A certain robustness in our conclusion is warranted as similar numbers were obtained via two separate approaches. The third model used several different parameters in order to ascertain that, in general, states that are projected to slow towards flat-line population growth and to become milder due to climate change such as Rhode Island, New York and Ohio are far more suitable with regard to an energy limited world than states that are projected to grow in population as well as become less mild due to climate change such as Texas, Arizona and Nevada. Each of these models in its own way foreshadows necessary changes that the world will experience as the 21st century progresses. The economies of the world have been, and continue to be, built on energy. When energy production is unable to continue growing it must follow that economies will be unable to grow. As the world approaches and passes peak energy, the standard of living in the less developed areas of the world cannot improve without sacrifices being made in the developed world.
46

Consuming Tourism : Future Implications and Possibilities

Rådestad, Caroline January 2011 (has links)
The purpose of the thesis at hand is to shed light on factors that will have impact on the future development of the tourism industry and the importance of preparing for them.  The main issue is the future availability of oil and the subsequent behaviour of consumers. In order to answer the questions posed for the purpose of the thesis at hand a number of interviews were carried out with people working in the tourism industry as well as people working within administrative authorities focused on environmental issues. In order to deepen the understanding for the topic of the thesis at hand extensive literary reviews were made and out of that material a state of the art was composed. In addition to this a number of theories on consumption and consumerism were used.  The empirical material showed that there were a number of factors that need to be dealt with in order for the tourism industry to be prepared for what might happen in the future. The future of the tourism industry is bright at least when considering the predictions of increasing arrival numbers and the revenue it will bring. On the other hand the tourism industry is facing many challenges in the future some of which cause more concern than others. For example tourism is greatly dependent on various forms of transportation in order to function. And transportation, especially aviation, is dependent on fuel to function. This means that when tourism increases so does transportation and with it oil consumption. Researchers are now predicting that the oil reserves are running out and that the risk of reaching a peak in oil production is drawing closer. At the moment the solutions to this problem are few and the fact that tourism is increasing steadily is not helping. The suggestion put forth in the thesis at hand is that consumption behaviours of tourists need to change in order to secure a sustainable future.   Tourism is a form of consumption and consumption is a natural part of human life and a function that is continuous. The way we consume naturally has consequences on many different levels in society. However the negative consequences related to consumption of tourism are shaping what our future will look like. Thus it is time for change.
47

Statistical Analysis and Dynamic Visualization of Travis Peak Production in the Eastern Texas Basin

Ayanbule, Babafemi O. 2010 August 1900 (has links)
Gas production has increased exponentially over the last 30 years, which is in response to the increasing demand for natural gas. This trend is speculated to continue to increase as legislation continues to be passed requiring power plants to reduce nitrogen oxide emissions. This recently happened in Colorado according to the Washington Post, giving more consideration to using natural gas. As natural gas becomes more popular there is a need to understand the production patterns and observable trends, integrating data from various sources. This research will attempt to do just that for wells producing from the Travis Peak formation. Using data from HPDI L.L.C., (www.hpdi.com) a visual representation was created for the areal distribution of peak gas rates and cumulative gas production. This allowed us to categorize wells by their production performance and we found that areas with relatively high peak gas rates also had high cumulative gas production. An analysis of these wells was done by completion year, and we found that wellhead prices of natural gas strongly influenced the annual number of new wells. We also found that the distribution of the annual number of new wells affected the average annual initial production rate and the peak gas rate of new wells. Wells located in areas of poor production performance were analyzed and it was apparent that newer wells performed relatively better than older ones and well stimulation is a major requirement for better gas production. Wells located in areas of good production performance were also analyzed and we found that the distribution of newer wells to older ones influenced the relative performance of individual wells. Overall, there was no observable trend between production variables in Travis Peak. No trend in production variable was found to be exclusively associated with good performing wells or poor performing wells.
48

The Study of IR-reflow Condition Variations on the Warpage of PBGA Packages

Yen, Jia-Jin 05 September 2001 (has links)
The main objective of this paper is to utilizing the Shadow Moir&#x00E9; method to study the effect of IR-reflow Condition Variations on the warpage of PBGA Packages. Two combinations of different moisture and temperature status are also chosen for the purpose of the study. The result shows that the first peak temperature is the most effective variable on the warpage of PBGA packages under the IR-reflow process.
49

Castle Peak Hospital redevelopment /

Li, Po-ling, January 1997 (has links)
Thesis (M. Arch.)--University of Hong Kong, 1997. / Includes special report study entitled: Complex circulation system. Includes bibliographical references.
50

The influence and controls of climate and geology on landforms : with special reference to the Castle Peak district.

Woo, Ming-Ko. January 1967 (has links)
Thesis (M.A.)--University of Hong Kong, 1967. / Mimeographed.

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