Ultra wideband (UWB) has the potential for high data rates, ranging and positioning. A UWB communication system's design requires knowledge regarding the channel. This thesis investigates the effect that different antenna orientations have on the wireless channel; in an indoor office environment. Channel reciprocity, path loss, body shadowing and spatial correlation are investigated for the frequency band 3.1 to 10.6 GHz. The measurements are performed in the frequency domain. UWB channels are shown to be highly reciprocal in all instances. Path loss versus distance was determined for line of sight (LOS) and non-line of sight (NLOS) scenarios. Body shadowing is measured for an average Caucasian male, and the root mean square (RMS) delay spread and received power loss plotted spatially. The spatial correlation is investigated using a two dimensional grid. A comparison between the horizontal and vertical polarization is made. / Graduate

Abstract The natural progression of generators and retailers, following electricity deregulation, to vertically integrate is a contentious subject involving, at one extreme, expectations that a laissez- faire market approach will deliver economic benefits to all participants, and at the other extreme, suspicions that the unusual features of the electricity sector, in providing generators with market power, may not provide electricity consumers with an improved outcome. The objectives of this thesis were to: understand fully the drivers of generators and retailers to vertically integrate and to apply this knowledge to the Queensland electricity market to determine the financial impact on generators, retailers and consumers from vertical integration (VI). A literature review was undertaken of VI in a generic sense, noting the distinction between market contracting and ‘internalisation’, with particular reference to the writings of Oliver Williamson. The Federal Court case involving Australia’s largest electricity retailer, Australian Gas and Light Ltd, seeking approval to purchase a minority shareholding in the Victorian generator Loy Yang Power, was closely examined from the perspectives of theoretical and practical electricity sector VI integration issues. A quantitative analysis was undertaken of an assumed 60% VI of the Queensland electricity market to assess the costs and benefits to generators that vertically integrated and to consumers. The quantified generator benefits included margin elimination, savings in overheads, more rapid decision-making, and demand side management (DSM) savings in deferred capital expenditure on peaking generation and network expenditure through reduced peak demand. To support the quantitative analysis, two scenario models were developed. The first model replicates the process by which generators build up revenue certainty over time from hedge contract sales and bidding of output into the electricity grid. How generator bidding behaviour is affected by the level of hedge cover and hedge contract prices is examined, particularly in regard to how this behavior is affected by the competitive relationship between retailers and generators. The second scenario model replicates the attitude of vertically integrated generators (VIGs) towards offering DSM services by observing how the attitude of individual VIGs is affected by level of peaking generation and by the generation-to-retailing output proportion. It was determined that a combination of these features and particular market scenarios could result in some VIGs being financially worse off by providing DSM services, an important conclusion in the context of the increased community focus on energy conservation. The extent to which VIGs pass on VI and DSM benefits to consumers was calculated under scenarios of weak and strong retail competition. Of most relevance was the difference in market behaviour between retailers that had became vertically integrated, and those that had not, with the latter expected to become less competitive in both the wholesale and retail markets. This outcome was observed to provide generators with additional market power potential, a subject closely examined. The quantitative analysis of the Queensland market concluded that the maximum possible benefit that consumers could expect from VI was $138 million per annum with current DSM technology and strong retail competition, increasing to $156 million per annum if DSM technology improved, for example in regard to more cost-efficient meters. Total possible benefits to VIGs and consumers was estimated at $321 million per annum, so that consumers could expect to receive no more than 50% of total expected benefits from VI. This conclusion is not surprising because generators will only seek to be vertically integrated if they perceive clearly identified benefits from VI. The reasons why consumers are unlikely to receive benefits greater than this are: • $30 million per annum of internal savings being retained by VIGs; • VIGs achieving a minimum $60 million per annum additional revenue benefits through wholesale and retail price increases, arising from their stronger generation and retail positions; and • $75 million per annum of potential DSM benefits not being offered to consumers, because of the reluctance of VIGs to provide DSM services where the outcome could be reduced export revenue, reduced sales revenue and lower pool prices. In summary, using the Queensland market as a case study, in a strongly competitive retail market consumers could expect to receive, at the most, 50% of VI and DSM benefits. However in a weakly competitive retail market, where VIGs retain most of the benefits and are able to achieve higher wholesale prices, the outcome could instead be an overall cost to consumers. The thesis concludes with a brief discussion of policy implications and approaches to addressing key issues arising from increasing VI in deregulated electricity markets.

Aim: The aim of this study was to investigate the differences between older and younger adults in the attenuation of impact during descent from a step. Strategies that have been implicated in reducing either the magnitude of vertical ground reaction force (vertical GRF) or the time taken to reach the maximum vertical GRF in the stepping leg were explored. Study Design: The study was an experimental, laboratory based, repeated measures design. Participants: Twenty participants took part in this exploratory study. Ten in the older group of 60-80 years, mean 65.3 (SD 5) years and ten in the younger age group of 20-30 years, mean 22.8 (SD 2.5) years. Main Measures: The vertical GRF and the time taken to reach maximum vertical GRF were measured to ascertain impact during step descent. Electromyography and kinematic variables were measured to determine the effect they may have on the impact. The variables measured were the maximum joint range of motion of the hip and knee during early stance in step descent. Surface electromyography from four lower limb muscles was recorded to ascertain the magnitude of muscle activity at impact. The relationship in an antero-posterior direction of the upper body and stepping leg at initial contact (IC) was also investigated. Results: There was a significant difference in both the amount of knee flexion and the amount of activity of the vastus lateralis muscle during impact between older and younger adults. Older adults had significantly less knee flexion during a step descent activity than younger adults (F(1,18)=5.48; p=.031).Older adults had significantly more vastus lateralis activity during a step descent activity than younger adults (F(1,18)=5.21; p=.035). Conclusions: Older and younger adults use different strategies in both muscle activation and joint range of motion around the knee of the leading leg during the step descent. Older adults used more vastus lateralis activity perhaps to increase stiffness in the knee, leading to a reduction in range of motion at impact. Although no change in vertical GRF was detected in this study, both of these strategies have the potential to increase the impact of a step and therefore cause jarring and possible damage. This study recruited healthy active older adults and differences in impact may be observed in an older or less active population, or in those with joint pathology such as osteoarthritis.

Aim: The aim of this study was to investigate the differences between older and younger adults in the attenuation of impact during descent from a step. Strategies that have been implicated in reducing either the magnitude of vertical ground reaction force (vertical GRF) or the time taken to reach the maximum vertical GRF in the stepping leg were explored. Study Design: The study was an experimental, laboratory based, repeated measures design. Participants: Twenty participants took part in this exploratory study. Ten in the older group of 60-80 years, mean 65.3 (SD 5) years and ten in the younger age group of 20-30 years, mean 22.8 (SD 2.5) years. Main Measures: The vertical GRF and the time taken to reach maximum vertical GRF were measured to ascertain impact during step descent. Electromyography and kinematic variables were measured to determine the effect they may have on the impact. The variables measured were the maximum joint range of motion of the hip and knee during early stance in step descent. Surface electromyography from four lower limb muscles was recorded to ascertain the magnitude of muscle activity at impact. The relationship in an antero-posterior direction of the upper body and stepping leg at initial contact (IC) was also investigated. Results: There was a significant difference in both the amount of knee flexion and the amount of activity of the vastus lateralis muscle during impact between older and younger adults. Older adults had significantly less knee flexion during a step descent activity than younger adults (F(1,18)=5.48; p=.031).Older adults had significantly more vastus lateralis activity during a step descent activity than younger adults (F(1,18)=5.21; p=.035). Conclusions: Older and younger adults use different strategies in both muscle activation and joint range of motion around the knee of the leading leg during the step descent. Older adults used more vastus lateralis activity perhaps to increase stiffness in the knee, leading to a reduction in range of motion at impact. Although no change in vertical GRF was detected in this study, both of these strategies have the potential to increase the impact of a step and therefore cause jarring and possible damage. This study recruited healthy active older adults and differences in impact may be observed in an older or less active population, or in those with joint pathology such as osteoarthritis.

Thesis (Ph. D.)--Michigan State University. Dept. of Economics, 2006. / Title from PDF t.p. (viewed on June 19, 2009) Includes bibliographical references (p. 110-112). Also issued in print.

Thesis (Ph. D.)--Georgia State University, 2009. / Title supplied by cataloger from ETD form. Omesh Kini, committee chair; Husayn Shahrur, Gerald Gay, Jayant Kale, Harley E. Ryan, committee members. Description based on contents viewed July 30, 2009. Includes bibliographical references.

Th. doct.--Géophys.--Grenoble 1, 1991. / 1992 d'après la déclaration de dépôt légal. Bibliogr. p. 251-255. Résumé en français et en anglais.

Thesis (Ph. D.)--University of Chicago, Dept. of Economics, August 1999. / Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 95-103).

Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 280-284). Available also in a digital version from Dissertation Abstracts.