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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

Do Thigh Circumference and Mass Changes Associated With Obesity Alter Walking Biomechanics?

Westlake, Carolyn Grace 01 May 2011 (has links)
Differences in gait biomechanics have been observed between obese and healthy weight adults. It is possible that body segment parameters, particularly the thigh, contribute to the differences in knee biomechanics observed during gait between obese and healthy weight adults. The purpose of this study was to determine if increases in thigh circumference and/or mass associated with obesity alter walking biomechanics in healthy weight males and females. Thigh mass and circumference were increased proportional to a 10 unit increase in body mass index. Frontal and sagittal plane knee angles and moments, and temporospatial variables were recorded. For all dependent variables no main effect for gender was observed. Peak knee flexion angle was similar across conditions with no interaction. There was an interaction for peak internal knee extension moment however post hoc comparisons did not reveal differences in condition among males or females. A main effect for condition was observed for peak knee adduction angle, however post hoc comparisons did not reveal differences among conditions. Peak internal knee abduction moment was similar across conditions with no interaction. Stance time and step width increased during the experimental conditions compared to the control. A interaction was observed for stance time. Females had a longer stance time during the circumference only condition compared to the control condition. A greater step width was observed in conditions that increased thigh circumference. Overall, thigh segment parameters altered gait temporospatial variables. Increases in stance time and step width in obese adults compared to healthy weight adults could be a result of their larger thigh segment parameters.
142

Rock art boundaries: considering geographically limited elements within the Pecos River Style

Harrison, James Burr 30 September 2004 (has links)
This thesis examines six prominent Pecos River Style rock art anthropomorph attributes to determine if they are found in limited geographic districts of the Lower Pecos Region. Both Boyd (2003) and Turpin (2004) have suggested that spatially-segregated motif distributions exist in the rock art and that these patterns are important in understanding regional prehistoric hunter-gatherer lifeways during the Archaic Period. This study verifies that the feather hip cluster motif is geographically limited, identified only in the neighboring Seminole and Painted Canyon systems. As part of this spatial analysis, the previously undocumented principle of intersite stylistic traditions is introduced. Possible explanations for these anthropomorph attributes are also discussed. Finally, structural analyses of the six attributes are presented.
143

Vad ska religionsämnet vara bra för? : En undersökning angående elevers uppfattning om religion och religionsundervisning från ett interkulturellt perspektiv

Matti, Sofia, Helge, Anna January 2006 (has links)
The purpose of this thesis is to investigate whether the lower secondary school teaching in religion leads to a positive understanding and openness, concerning different religions and cultures. We want to study how pupils in grade eight and nine in two lower secondary schools in a multicultural community comprehend different religions. Since we choose a pupils perspective we decided to do a questionnaire to get a wide ground. As a complement we interviewed twelve pupils and also did observations during their religion classes. During our study we focused on three different themes. These themes are the abrahamitic religions (Christianity, Judaism and Islam) Hinduism & Buddhism and attitudes to religion. Our theoretical point of view is the intercultural perspective. Therefore we have studied government’s documents and propositions about intercultural education and we have also used an anthology by Pirjo Lahdenperä called Interkulturell pedagogik i teori och praktik (2004). We aim to investigate if the teaching in religion is compatible with the intercultural education. The thesis reveals that there are lots of prejudices among the pupils in these two schools. We think that it is important that the teaching in religion must focus not only at the Christianity in younger ages. The subject must contain other religions like Islam, Judaism, Hinduism and Buddhism in much earlier age. Otherwise the pupils will create their own picture of the different religions through media. The Swedish governments goals about school (LPO 94) and the document about the teaching in religion (kursplanen i religionskunskap) both can, according to us, be used as tools for intercultural education. The problem is that the teachers do not know how to use these tools. The methods of intercultural education must be clearer and the teachers more conscious. Before that happens, we can not state that the education is totally intercultural. We have a big challenge in front of us when we finally will step out on the labour market!
144

Effektiv prissättning av OMXS-optioner : En empirisk undersökning

Sener, Johnny, Svensson, Anders January 2006 (has links)
I uppsatsen har vi undersökt köpoptioner med OMXS30 som underliggande, syftet var att se om det fanns möjligheter till att göra arbitrage. Detta innebär att de är felprissatta. Vi har i vår undersökning testat optioners nedre gräns och köp-sälj paritetsvillkoret. Resultaten tyder på att det finns ett antal tillfällen då marknaden inte är effektiv, antalet tillfällen skiljer sig åt under olika marknadsförhållanden. De slutsatser vi kan dra är att marknaden måste vara mogen och marknadens aktörer måste ha en tydlig bild om i vilken riktning marknaden är på väg för att vi ska kunna säga att optionspriserna är effektivt prissatta. När investerare agerar irrationellt och osäkerheten är hög ökar frekvensen av antalet felprissättningar på finansiella instrument, däribland optioner.
145

Data Structuring Problems in the Bit Probe Model

Rahman, Mohammad Ziaur January 2007 (has links)
We study two data structuring problems under the bit probe model: the dynamic predecessor problem and integer representation in a manner supporting basic updates in as few bit operations as possible. The model of computation considered in this paper is the bit probe model. In this model, the complexity measure counts only the bitwise accesses to the data structure. The model ignores the cost of computation. As a result, the bit probe complexity of a data structuring problem can be considered as a fundamental measure of the problem. Lower bounds derived by this model are valid as lower bounds for any realistic, sequential model of computation. Furthermore, some of the problems are more suitable for study in this model as they can be solved using less than $w$ bit probes where $w$ is the size of a computer word. The predecessor problem is one of the fundamental problems in computer science with numerous applications and has been studied for several decades. We study the colored predecessor problem, a variation of the predecessor problem, in which each element is associated with a symbol from a finite alphabet or color. The problem is to store a subset $S$ of size $n,$ from a finite universe $U$ so that to support efficient insertion, deletion and queries to determine the color of the largest value in $S$ which is not larger than $x,$ for a given $x \in U.$ We present a data structure for the problem that requires $O(k \sqrt[k]{{\log U} \over {\log \log U}})$ bit probes for the query and $O(k^2 {{\log U} \over {\log \log U}})$ bit probes for the update operations, where $U$ is the universe size and $k$ is positive constant. We also show that the results on the colored predecessor problem can be used to solve some other related problems such as existential range query, dynamic prefix sum, segment representative, connectivity problems, etc. The second structure considered is for integer representation. We examine the problem of integer representation in a nearly minimal number of bits so that increment and decrement (and indeed addition and subtraction) can be performed using few bit inspections and fewer bit changes. In particular, we prove a new lower bound of $\Omega(\sqrt{n})$ for the increment and decrement operation, where $n$ is the minimum number of bits required to represent the number. We present several efficient data structures to represent integers that use a logarithmic number of bit inspections and a constant number of bit changes per operation.
146

Data Structuring Problems in the Bit Probe Model

Rahman, Mohammad Ziaur January 2007 (has links)
We study two data structuring problems under the bit probe model: the dynamic predecessor problem and integer representation in a manner supporting basic updates in as few bit operations as possible. The model of computation considered in this paper is the bit probe model. In this model, the complexity measure counts only the bitwise accesses to the data structure. The model ignores the cost of computation. As a result, the bit probe complexity of a data structuring problem can be considered as a fundamental measure of the problem. Lower bounds derived by this model are valid as lower bounds for any realistic, sequential model of computation. Furthermore, some of the problems are more suitable for study in this model as they can be solved using less than $w$ bit probes where $w$ is the size of a computer word. The predecessor problem is one of the fundamental problems in computer science with numerous applications and has been studied for several decades. We study the colored predecessor problem, a variation of the predecessor problem, in which each element is associated with a symbol from a finite alphabet or color. The problem is to store a subset $S$ of size $n,$ from a finite universe $U$ so that to support efficient insertion, deletion and queries to determine the color of the largest value in $S$ which is not larger than $x,$ for a given $x \in U.$ We present a data structure for the problem that requires $O(k \sqrt[k]{{\log U} \over {\log \log U}})$ bit probes for the query and $O(k^2 {{\log U} \over {\log \log U}})$ bit probes for the update operations, where $U$ is the universe size and $k$ is positive constant. We also show that the results on the colored predecessor problem can be used to solve some other related problems such as existential range query, dynamic prefix sum, segment representative, connectivity problems, etc. The second structure considered is for integer representation. We examine the problem of integer representation in a nearly minimal number of bits so that increment and decrement (and indeed addition and subtraction) can be performed using few bit inspections and fewer bit changes. In particular, we prove a new lower bound of $\Omega(\sqrt{n})$ for the increment and decrement operation, where $n$ is the minimum number of bits required to represent the number. We present several efficient data structures to represent integers that use a logarithmic number of bit inspections and a constant number of bit changes per operation.
147

Metapopulation Ecology and Recovery of the Endangered Lower Keys Marsh Rabbit

Schmidt, Paige McGee 2009 December 1900 (has links)
The Lower Keys marsh rabbit (LKMR, Sylvilagus palustris hefneri), a subspecies of marsh rabbit endemic to the Lower Keys, Florida, is threatened with extinction due to extensive coastal development of salt marsh habitats. LKMR recovery is limited by habitat loss and degradation from brush encroachment, predation by freeroaming cats (Felis catus) and raccoons (Procyon lotor), sea-level rise, and hurricanes. This study sought to determine local and landscape factors that influence LKMR metapopulation ecology and dynamics and to evaluate strategies for their recovery. I evaluated the influence of patch and landscape characteristics on LKMR densities, extinction, and colonization rates following Hurricane Wilma, and the response of LKMRs and salt marsh habitats to prescribed fire. I used estimates of population change based on annual monitoring data to validate vital rates, constructed a spatially explicit demographic model to evaluate various levels and spatial configurations of recovery scenarios implemented throughout the LKMRs range, and validated expected changes in parameter estimates using measures of habitat degradation and raccoon activity from known LKMR populations. I found LKMR densities were higher in patches with greater numbers of bunchgrasses and forbs and less edge and lower in patches with higher measures of raccoon activity. In response to a hurricane, I found the distance between LKMR patches and the coast had a negative influence on extinction probability; the distance between an extirpated and occupied LKMR patch had a negative influence on colonization probability and patch size had a positive influence. Adult LKMRs increased as woody cover <0.5 m decreased, herbaceous cover <0.5 m increased, and food availability increased in at least one site following prescribed fire. Model results indicated habitat management actions that improve carrying capacity of local rabbit populations and juvenile survival and control raccoon populations to increase rabbit reproductive rates are effective population recovery strategies. In total, my results provide a conservation planning tool that can be used to select recovery strategies and locations that will maximize benefits to LKMRs, thus improving their viability and recovery.
148

Sub-Nyquist Rate Sampling Data Acquisition Systems Based on Compressive Sensing

Chen, Xi 2011 May 1900 (has links)
This dissertation presents the fundamental theory and design procedure of the sub-Nyquist rate sampling receiver front-end that exploits signal sparsity by employing Compressive Sensing (CS) techniques. The CS receiver serves as an Analog-to-Information Conversion (AIC) system that works at sampling rates much lower than the Nyquist rate. The performance of a parallel path CS front-end structure that employs current mode sampling techniques is quantified analytically. Useful and fundamental design guidelines that are unique to CS are provided based on the analytical tools. Simulations with IBM 90nm CMOS process verify the theoretical derivations and the circuit implementations. Based on these results, it is shown that instantaneous receiver signal bandwidth of 1.5 GHz and 44 dB of signal to noise plus distortion ratio (SNDR) are achievable in simulations assuming 0.5 ps clock jitter is present. The ADC and front-end core power consumption is estimated to be 120.8 mW. The front-end is fabricated with IBM 90nm CMOS process, and a BPSK sub-Nyquist rate communication system is realized as a prototype in the testing. A 1.25 GHz reference clock with 4.13 ps jitter variance is employed in the test bench. The signal frequency, phase and amplitude can be correctly reconstructed, and the maximum signal SNR obtained in the testing is 40 dB with single tone input and 30 dB with multi-tones test. The CS system has a better FOM than state-of-art Nyquist rate data acquisition systems taking into account the estimated PLL power.
149

A Study on the Design of Auxiliary Walking Mechanisms for Lower Limb Disablement

Chen, Yu-ting 08 September 2006 (has links)
Orthoses and auxiliaries are important to the people with lower limb disabled in their daily lives. The purpose of this study is to survey and discuss the existing walking auxiliary mechanism for the lower limb disabled people, and to design a new walking auxiliary mechanism to improve their walking gesture. In order to develop a new auxiliary mechanism for the people with lower limb disabled, commercial orthoses and patents are colleted, analyzed, classified, and compared to each others. Several interviews with a lower limb disablement are arranged and understand what they need. After integrating all the collected information as the design input, theories of mechanism structure synthesis, dimension synthesis, mechanism analysis are utilized to develop a mechanism design of auxiliary for lower limb disabled people to walk, to go up and down the stair. The Pro-Engineering, a CAD software, is used for solid modeling and the Visual Nastran, a CAE software, is applied for motion simulation. The results of computer simulations of walking and climbing up stairs are compared to that of video taken from the interviewed people.
150

Minimum Diameter Double-Loop Networks

Gao, Ying-Yao 21 July 2002 (has links)
Abstract ¡@¡@Double-loop networks have become one of the most popular architectures in the design of Local Area Networks and distributed memory multiprocessor systems. This is due to its characters of minimal diameter, easy routing, expandability and regularity. The switching mechanism at each node can easily be implemented using building blocks of the same specification. Therefore, double-loop networks have a high degree of reliability and hence very low vulnerability. Let N denote the number of nodes in a double-loop network and d(N) be the best possible diameter with N vertices. Given an N, Bermond et al. [5], Boesch and Wang [7], and Yebra et al. [23] have shown that . This is a well-known lower bound for d(N) and is usually denoted as lb(N). In this paper, what we discuss is finding an optimal topology such that d(N)= lb(N) for any given value of N. We provide a simple formula to find optimal topologies of double-loop networks with N nodes.

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