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The purpose of this study was to examine the caloric intake and energy output of swimmers and runner during normal daily activities and training. Daily and energy expenditure of twenty college varsity swimmers and runners were measured. Four groups of subjects were categorized as male runners, female runners, male swimmers, and female swimmers with five subjects in each group. An additional twenty runners and swimmers recorded only dietary intake. Despite a large difference in body weight and body fat, the mean daily caloric intake was similar for the two groups (male swimmers: 3377 Kcal/d-1, male runners: 3463 Kcal/d-1, female swimmers: 2491 Kcal/d-1, female runners: 2037 Kcal/d-1). Comparison of data normalized for body weight showed that male runners were more active than swimmers. Male runners burned more calories (53.3 Kcal/kg. d-1) in a twenty four hour period than swimmers (47.6 Kcal/kg.d-1). In the case of the females, the trend was reversed. Female swimmers expended more calories (45 Kcal/kg .d-1) than runners (38.9 Kcal/kg.d-1) despite a lower food intake. Consequently, caloric intake and life style does not seem to explain body fat difference between runners and swimmers. The data in this study suggest that the greater body fat found in swimmers may be related to a physiological adaptation induced by swim training.

Wind generation presents variability on every time scale, which must be accommodated by the electric grid. Limited quantities of wind power can be successfully integrated by the current generation and demand-side response mix but, as deployment of variable resources increases, the resulting variability becomes increasingly difficult and costly to mitigate. In Chapter 2, we model a co-located power generation/energy storage block composed of wind generation, a gas turbine, and fast-ramping energy storage. A scenario analysis identifies system configurations that can generate power with 30% of energy from wind, a variability of less than 0.5% of the desired power level, and an average cost around $70/MWh. While energy storage technologies have existed for decades, fast-ramping grid-level storage is still an immature industry and is experiencing relatively rapid improvements in performance and cost across a variety of technologies. Decreased capital cost, increased power capability, and increased efficiency all would improve the value of an energy storage technology and each has cost implications that vary by application, but there has not yet been an investigation of the marginal rate of technical substitution between storage properties. The analysis in chapter 3 uses engineering-economic models of four emerging fast-ramping energy storage technologies to determine which storage properties have the greatest effect on cost-of-service. We find that capital cost of storage is consistently important, and identify applications for which power/energy limitations are important. In some systems with a large amount of wind power, the costs of wind integration have become significant and market rules have been slowly changing in order to internalize or control the variability of wind generation. Chapter 4 examines several potential market strategies for mitigating the effects of wind variability and estimate the effect that each strategy would have on the operation and profitability of wind farms. We find that market scenarios using existing price signals to motivate wind to reduce variability allow wind generators to participate in variability reduction when the market conditions are favorable, and can reduce short-term (30-minute) fluctuations while having little effect on wind farm revenue.

The Li-oxygen cell is an emerging energy storage system which has a great promise in the near future for its high energy density and use of free oxygen available from the air. This energy system is attractive since it has nine times higher energy density than conventional lithium-ion cells based on LiCoO2 and graphite. However, this deceptively simple system poses many challenges which must be overcome before it could be considered for any practical application. Firstly, the formation of the insulating and insoluble reaction product, lithium peroxide, requires the highly porous, yet electronically well percolated cathode structure for the reasonable performance. Secondly, the decomposition of lithium peroxide usually involves the huge anodic overpotential which requires the development of highly efficient catalyst. Thirdly, a proper electrolyte system should be developed which is resistant to both the superoxide attack during the discharge reaction and the highly oxidizing environment during the charge process where both oxygen radicals and catalysts are present. Lastly, protection of the lithium anode is necessary, otherwise oxygen radicals in the solvent will react with lithium metal spontaneously, which eventually increases the impedance and more importantly depletes lithium metal from the anode. This thesis is primarily focused on the development of highly efficient catalysts for oxygen reduction and oxygen evolution reactions for the rechargeable Li-oxygen battery. To this end, a highly porous and electrically networked cathode film was manufactured by utilizing common plasticizers as pore forming agents and a Li-oxygen testing cells were developed using Swagelok??? fittings. The Li-oxygen cell test in two different electrolyte systems shows that the reactivity of electrolyte system to superoxide radicals is a key parameter to determine the nature of reaction product. For LiBOB/PC system, both LIBOB and PC are actively decomposed by superoxide radicals to produce lithium oxalate and lithium carbonate as main discharge products. In the case of LiPF6/TEGDME system, both salt and solvent are stable and thus ideal discharge product, lithium peroxide is obtained. Lead ruthenate and bismuth ruthenate with the extended pyrochlore structure show an excellent catalytic activity by increasing discharge capacity and lowering the anodic overpotential considerably during charge process in both electrolyte systems. They reduce the decomposition of electrolyte system and the extent of carbon corrosion, which accounts for more efficient cycling. The excellent catalytic activity of these pyrochlores originates from their intrinsic oxygen vacancies, electronic conductivity and many surface active sites afforded by its morphology. The performance of this catalyst was further increased through gold deposition on the pyrochlore surface, resulting in much increased discharge capacity. The pyrochlore coated carbon was proposed as a type of catalyst for an efficient way to reduce the amount of catalyst and enhance homogenous mixing with other components. The investigation on the lithium peroxide decomposition mechanism shows that carbon corrosion which occurs at around 4.0 V by lithium peroxide makes further decomposition difficult without a catalyst. In the presence of catalyst, almost full decomposition of lithium peroxide occurs with a lowered decomposition potential even though carbon corrosion still occurs. This gives a hint that the generation of a nano-porous structure and the homogenous distribution of catalyst over these pores are very important, as well as use of a highly efficient catalyst for lowering activation overpotentials. In conclusion, although there are still many obstacles present, as listed above, for the commercial application of Li-oxygen cell, these hurdles are surmountable in the near future by intensive research and the results shown in this thesis can be a cornerstone for further research. Supercapacitors based on metal oxide are new energy storage devices for ultrafast charging and discharging with decent energy density over hundreds of thousands of cycles for many commercial electronic devices and power tools. The surface redox nature of these reactions requires the creation of high surface area for better utilization and performance. Hydrous ruthenium dioxide is one of the most attractive supercapacitor materials owing to its high pseudo-capacitance and metallic character, which facilitate fast electron movement. In this thesis, a simple process involving soft liquid crystal templating using cationic surfactant and gentle heat-treatment in the mild temperature was developed to prepare mesoporous ruthenium oxide with a quasi-crystalline wall character, which has a high surface area and controlled water contents in the structure. The electrochemical testing results exhibited a promising performance of high gravimetric capacitance and a good rate capability facilitated by high surface area as well as porous structure.

<p> In 2007, vacation rental properties in the United States accounted for more than 22% of the domestic lodging market. These properties are a unique segment of the lodging industry due to their residential design and commercial use. Coastal vacation rental properties represent the largest supply, demand and value of the nation's vacation rental supply. In the case of North Carolina's Outer Banks, tourism is the area's largest source of income, with vacation real estate agencies being the largest accommodation provider. This study uses a multiple regression analysis to investigate the energy consumption of 30 vacation rental homes on Hatteras Island. Hatteras Island's abundant supply of vacation rental homes provided a diverse sample to study energy consumption with a wide range of houses regarding size, age, and location. Since very little research has been conducted on the energy consumption of vacation rental homes, this study aims to contribute detailed information regarding the energy consumption of unique accommodation sector.</p>

The transient thermal history of a well drilling system has been identified as one of the main problems that the geothermal well drilling industry needs to solve. In particular, the estimation of temperatures, in and around a geothermal well during drilling (circulation) and shut-in (thermal recovery) conditions, is required. To overcome this problem, a computer simulator (WELLTHER) has been developed which uses a direct solution method to solve the finite difference equations describing the transient heat transfer processes in a wellbore during drilling and shut-in operations in the presence of the lost circulation to the formation. The new computer simulator uses a numerical model to account for the transient convective heat transfer in the formation surrounding a well, due to lost circulation. This feature of the present simulator is important, since previous wellbore simulators consider the heat transfer process in the formation (rock) as a merely conductive problem. The WELLTHER simulator is capable of accounting for these losses at any point in the well and it has been applied to the study of several Mexican geothermal wells. The results show that the effect of lost circulation on the shut-in temperature profiles can be reproduced satisfactorily. Likewise, a parametric analysis, carried out using the simulator, indicates that a number of assumptions made in previous numerical models are invalid and that certain factors ignored in previous models have a significant effect on the dynamic wellbore temperature distribution. Finally, a coupling of the new simulator with another computer code (STATIC TEMP) can be used as a tool to infer more reliably the static formation temperatures in geothermal systems.

Energy is the material foundation of human survival and development. Throughout human industrialization process, the fossil energy has made tremendous contributions in the progress of human civilization, economic and social development. For a long time, the development of human energy use patterns makes fossil fuels rapidly depleted and the consequences of environmental deterioration by this pattern lead to the severe challenge for mankind. Many countries start paying more attention to develop the new energy. The solar electricity production system is one of the main new energy power generations. The thesis is a guide of principle for solar power generation system. It focuses on comparisons between photovoltaic and concentrating solar power generations and analysis of their market prospects. The merits and demerits of these two systems will also be pointed out in this thesis.

This research investigates the ???earth / human equation???, in which the land is identified as the indispensable nutrient for human existence. Observation of the ongoing processes of exploitation of the land and the images that result from this, leads to a questioning of some of the Western ideas and concepts that provided the legal and ethical framework for colonisation. A perceived connection between material form and energy as the fundamental paradigm for my studio practice informs my enquiry into theories about energy and its representation. I have chosen to methodologically allegorise and illustrate human dependence upon and connection to the earth by a series of references located in science and spirituality. Concepts of energy, codification and pattern are seen in the terms of ???exchangeable currency???, where organic models function as a ???template??? informing a philosophical framework, illustrative of the complexities of the relationship between earth and people. Within this hybrid structure, part hard science and part intuitive interpretation, some of the patterns formed in the exchange of energy between the earth and its peoples are interpreted in terms of a cultural stance and siting of the land in relation to the self.

Programm--k. Gewerbschule und Baugewerkenschule zu Zittau.