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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.
191

Effect of leg muscle fatigue on the contributions of the somatosensory, visual, and vestibular systems to balance

Korioukhina, Maia O. 28 April 2003 (has links)
Objectives: To evaluate the effect of leg muscle fatigue on balance and to determine the contributions of the somatosensory, visual, and vestibular systems to balance of apparently healthy males and females. Design: Forty-two subjects were randomly assigned to either the experimental or control groups and then subdivided based on gender resulting in four groups (10 men/women in the experimental groups and 11 men/women in the control groups). Each subject was pre-tested on the Sensory Organization Test assessment of balance. Subjects in the experimental group then underwent a Wingate Anaerobic Test to induce leg fatigue. Following the Wingate Test subjects were post-tested on the Sensory Organization Test. Subjects in the control group rested quietly for a period of seven minutes prior to post-testing. Subjects: Forty-two volunteers without recent or chronic history of lower extremity injury, neurological deficits, or balance problems participated. Main outcome measures: Ratios for the use of the somatosensory, visual, and vestibular systems and the Composite Score were calculated. A [2(Group) x 2(Gender) x 2(Test)] mixed design ANOVA was used to analyze each of the dependent variables. Results: Analysis of Composite Score demonstrated a significant Group x Test interaction (p<0.010). The breakdown of the interaction showed no significant Test effect (p-value 0.341) for the experimental group. However, there was a significant Test effect (p-value<0.010) for the control group. There were no significant effects of fatigue on somatosensory system ratio. The analysis of the visual system ratio revealed a significant main effect (p-value 0.022) for Group. Analysis of vestibular system ratio revealed a significant main effect for Test (p<0.010). Conclusions: As demonstrated by the results of the present experiment, leg muscular fatigue is associated with significantly decreased balance. In addition, fatigue does appear to have an effect on the utilization of visual and vestibular systems. / Graduation date: 2003
192

Efficiency and redistribution in economies with hidden action

Panaccione, Luca 05 September 2006 (has links)
In this thesis, we study how the efficiency of competitive equilibrium in a pure exchange economy with hidden action depends on the market structure. We consider both competitive anonymous markets, where consumers make their choices taking as given some relevant economic parameters, and competitive strategic markets, where consumers interact with financial intermediaries who explicitly take into account the choices of other economic agents. In the first chapter, we review some known results on the efficiency of competitive equilibrium under different market structures. In the second chapter, we assume that there are multiple consumption goods and that the level of action affects the marginal benefit consumers get from consumption. We consider two different market structures: a complete set of contingent-commodity markets, and a complete set of financial markets, together with spot markets for consumption goods. The main result we provide in this chapter is that under more general hypothesis than those usually considered in the literature, the equilibrium with financial markets is not efficient. In the third chapter, we assume that consumers can insure themselves by voluntarily committing to deliver part of their endowment to a common pool in exchange for a sure return from the pool itself. We show that an equilibrium with pool of promises exists, and we characterize it.
193

Changes in dynamic balance in multiple sclerosis patients as related to the severity of disease and self-rated fatigue

Miller, Caralynne M. January 2006 (has links)
Thesis (M.S.)--University of Delaware, 2006. / Principal faculty advisor: James G. Richards, College of Health Sciences. Includes bibliographical references.
194

Recovery of motor and cognitive function following concussion /

Parker, Tonya Moreland, January 2006 (has links)
Thesis (Ph. D.)--University of Oregon, 2006. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 113-119). Also available for download via the World Wide Web; free to University of Oregon users.
195

Efficiency and redistribution in economies with hidden action

Panaccione, Luca 05 September 2006 (has links)
In this thesis, we study how the efficiency of competitive equilibrium in a pure exchange economy with hidden action depends on the market structure. We consider both competitive anonymous markets, where consumers make their choices taking as given some relevant economic parameters, and competitive strategic markets, where consumers interact with financial intermediaries who explicitly take into account the choices of other economic agents. In the first chapter, we review some known results on the efficiency of competitive equilibrium under different market structures. In the second chapter, we assume that there are multiple consumption goods and that the level of action affects the marginal benefit consumers get from consumption. We consider two different market structures: a complete set of contingent-commodity markets, and a complete set of financial markets, together with spot markets for consumption goods. The main result we provide in this chapter is that under more general hypothesis than those usually considered in the literature, the equilibrium with financial markets is not efficient. In the third chapter, we assume that consumers can insure themselves by voluntarily committing to deliver part of their endowment to a common pool in exchange for a sure return from the pool itself. We show that an equilibrium with pool of promises exists, and we characterize it.
196

Essays on the inventory theory of money demand

Li, Chen 05 1900 (has links)
The goal of this dissertation is to examine the theoretical and empirical implications of the inventory theoretic approach to the demand for money. Chapter 1 reviews the existing inventory theoretic frameworks and empirical money demand literature and provides an overview of this thesis. One of the main conclusions is that the elasticity results from the existing inventory theoretic models are not robust. Chapter 2 develops a partial equilibrium inventory theoretic model, in which a fixed cost is involved per cash transfer. The key feature is that a firm endogenously chooses the frequency of pay periods, which a household takes as given. When the firm must borrow working capital and pay wages by cheque, I show that both the firm and the household choose to transfer cash every payday only. The model keeps the basic result from the classical inventory theoretic approach that both the income and interest elasticity of money demand are 0.5. Chapter 3 extends the partial equilibrium model into a general equilibrium framework and shows that the partial equilibrium elasticity results no longer apply in the general equilibrium. First, the income elasticity is 1 in the general equilibrium. Second, the interest elasticity has two values depending on a threshold interest rate. When interest rates are below this threshold, the model is the Cash-In-Advance model with a constant income velocity of money and zero interest elasticity; otherwise the interest elasticity is close to 0.5 and the velocity fluctuates in response to variations in interest rates. Finally, the general equilibrium elasticity results are robust across alternative specifications of the agent's utility. Chapter 4 calibrates the general equilibrium model to the last 40 years of US data for M1. By constructing a residual measure of money transaction costs from the structural money demand function, I find that a structural break in the transaction costs occurred in 1981 might have been responsible for the instability of long-run money demand. The benefit of this approach is that it can explain this pattern of money demand without appealing to an exogenous structural break in the money demand function.
197

Multiphase flow and chemical reactor thermodynamics for hydrolysis and thermochemical production

Pope, Kevin 01 August 2012 (has links)
Current techniques of hydrogen production (primarily reformation of fossil fuels) are unsustainable, releasing CO2 into the atmosphere, as well as consuming limited reserves of fossil fuels. The copper-chlorine cycle is a promising thermochemical process which can cost-effectively produce hydrogen with less environmental impact. In this thesis, new predictive formulations and experimental data are presented to improve the conversion extent and reaction rates of the hydrolysis reactor in the Cu-Cl cycle. This reactor has critical implications for the design, operation, and efficiency of the Cu-Cl cycle and hydrogen production. The relatively high temperature needed to drive the reaction requires a significant input of thermal energy. This thesis focuses on methods and analysis to reduce the unreacted steam in the hydrolysis reactor, in order to reduce the thermal energy input and improve the cycle’s thermal efficiency. A key outcome from this thesis is the experimental verification of reducing the steam to copper chloride ratio from 16:1 (past studies) to about 3:1. The results of this thesis provide key new data to design a more efficient hydrolysis reactor that can be effectively integrated within the Cu-Cl cycle. / UOIT
198

Molecular reorientation of some fatty acids when in contact with water.

Yiannos, Peter N. 01 January 1960 (has links)
No description available.
199

The impacts of improving Brazil's transportation infrastructure on the world soybean market

Costa, Rafael de Farias 15 May 2009 (has links)
The lack of adequate transportation infrastructure in Brazil has been a bottleneck for the soybean producers for many years. Moreover, the costly inland transportation incurred from this bottleneck has resulted in a loss in competitiveness for Brazil compared to other exporting countries, especially the United States. If transportation costs are reduced by introducing improved infrastructure, Brazil is expected to increase its competitiveness in the world soybean market by increasing its exports and producer revenues. On the other hand, the United States and other significant soybean competing exporting countries are expected to lose market share as well as producer revenues. This study uses a spatial equilibrium model to analyze transportation infrastructure improvements proposed by the Brazilian government vis-à-vis enhance the nation’s soybean transportation network. The analyzed transportation improvements are: (i) the development of the Tapajós-Teles Pires waterway; (ii) the completion of the BR- 163 highway; (iii) the construction of the Mortes-Araguaia waterway; (iv) the Ferronorte railroad expansion to Rondonópolis and the linkage between the city of Rio Verde to Uberlândia; and (v) the Ferropar railroad expansion to the city of Dourados. The model specifies the Brazilian inland transportation network and the international ocean shipments. The model divides Brazil into 18 excess supply regions and 8 excess demand regions. The competing exporting countries are the United States, Argentina, Rest of South America (Bolivia, Paraguay, and Uruguay), Canada, and India. The importing countries are composed of China, European Union, Southeast Asia, Mexico, and the Rest of the World. Results suggest these proposed transportation improvements yield potential noteworthy gains to Brazil with producer revenues increasing more than $500 million and exports increasing by 177 thousand metric tons. Consequently, the world soybean price declines by $1.16 per metric ton and producer revenues and exports in the United States fall by 63 thousand metric tons and $104.89 million, respectively. Although the absolute gains in price, revenues, and exports for Brazil are considerable, they only represent in relative changes 1.48, 2.35, and 0.32 percent, respectively. Similarly, the loss in price, revenue, and export value for the United States is also low, declining by 0.23, 0.23, and 0.12 percent, respectively.
200

The impacts of improving Brazil's transportation infrastructure on the world soybean market

Costa, Rafael de Farias 10 October 2008 (has links)
The lack of adequate transportation infrastructure in Brazil has been a bottleneck for the soybean producers for many years. Moreover, the costly inland transportation incurred from this bottleneck has resulted in a loss in competitiveness for Brazil compared to other exporting countries, especially the United States. If transportation costs are reduced by introducing improved infrastructure, Brazil is expected to increase its competitiveness in the world soybean market by increasing its exports and producer revenues. On the other hand, the United States and other significant soybean competing exporting countries are expected to lose market share as well as producer revenues. This study uses a spatial equilibrium model to analyze transportation infrastructure improvements proposed by the Brazilian government vis-à-vis enhance the nation's soybean transportation network. The analyzed transportation improvements are: (i) the development of the Tapajós-Teles Pires waterway; (ii) the completion of the BR- 163 highway; (iii) the construction of the Mortes-Araguaia waterway; (iv) the Ferronorte railroad expansion to Rondonópolis and the linkage between the city of Rio Verde to Uberlândia; and (v) the Ferropar railroad expansion to the city of Dourados. The model specifies the Brazilian inland transportation network and the international ocean shipments. The model divides Brazil into 18 excess supply regions and 8 excess demand regions. The competing exporting countries are the United States, Argentina, Rest of South America (Bolivia, Paraguay, and Uruguay), Canada, and India. The importing countries are composed of China, European Union, Southeast Asia, Mexico, and the Rest of the World. Results suggest these proposed transportation improvements yield potential noteworthy gains to Brazil with producer revenues increasing more than $500 million and exports increasing by 177 thousand metric tons. Consequently, the world soybean price declines by $1.16 per metric ton and producer revenues and exports in the United States fall by 63 thousand metric tons and $104.89 million, respectively. Although the absolute gains in price, revenues, and exports for Brazil are considerable, they only represent in relative changes 1.48, 2.35, and 0.32 percent, respectively. Similarly, the loss in price, revenue, and export value for the United States is also low, declining by 0.23, 0.23, and 0.12 percent, respectively.

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