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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.
701

Immigration: An Expedient Complement To Disaster Response? An Examination of Canada's Post-Earthquake Immigration Measures for Haiti and the Influence of the Haitian Diaspora in Canada

D'Aoust, Sarah 19 March 2012 (has links)
The Canadian response following the Haitian earthquake of 2010 was not solely focused on providing humanitarian assistance. Canada also used several immigration measures both at the federal level and the provincial level in Quebec in order to facilitate the immigration of eligible Haitians to Canada and their subsequent reunification with their Canadian family members. This thesis explores these immigration measures and evaluates their effectiveness. In addition, the research examines the role that the large Haitian Diaspora in Canada played in bringing about the adoption of a set of immigration measures specifically for Haitians. The research shows that the Canadian measures implemented were both multi-dimensional – as a variety of immigration mechanisms were used, and multi-level – as the Canadian response included both federal and provincial initiatives in Quebec. While a number of measures were introduced federally, none of these measures could be considered “special” as they were all possible under Canada’s immigration legislation, and they were not unique to the post-earthquake context. In contrast, Quebec’s Humanitarian Sponsorship Program for Haitians was very “special” in that it was the first time such a program was implemented for a large group of people. The research also points to the fact that although using immigration mechanisms to respond to a humanitarian crisis has its benefits, these mechanisms are not designed to provide prompt protection and relief to individuals affected by crisis situations. The research also demonstrates that the use of the available complementary protection measures (humanitarian and compassionate considerations, moratorium and protected person status) did not make up the primary thrust of the Canadian immigration response to the earthquake in Haiti. This fact is indicative of the inadequacy of these measures in providing protection to individuals displaced by environmental factors. Finally, it is argued that although the existence of a large Haitian Diaspora was influential in creating a climate open to the adoption of special measures for Haitians, the Haitian Diaspora did not necessarily influence the specifics of the measures adopted to a significant degree.
702

Dynamic Response And Permanent Displacement Analysis Of Akkopru Dam

Ulgen, Deniz 01 January 2004 (has links) (PDF)
In this study, dynamic response of Akk&ouml / pr&uuml / Dam under earthquake motions is analyzed and the permanent displacements are evaluated. Initially, the critical slip surface of the dam and the corresponding yield acceleration are determined by using the computer program SLOPE. Then, by employing the finite element program SAP2000, static analyses are performed to obtain the mean effective stresses which are used in the determination of dynamic material properties of the dam. Four different scenario earthquakes having a magnitude of 7 are used in the dynamic analyses. Two of those scenarios are taken from European Strong Motion Database and the others are generated by XS artificial earthquake generation program prepared by Erdik (1992). Dynamic analyses of the dam are carried out by the finite element program TELDYN. Permanent displacements of the critical slip surface are calculated by utilizing the Newmark method. Consequently, for an earthquake having a magnitude of M=7 and a peak ground acceleration of 0.20g, the maximum permanent displacement of the dam is found to be 15.90 cm. Furthermore, the permanent displacements of the dam are calculated under base motions having different peak ground acceleration values and it is observed that the rate of increase in the amount of permanent displacements is greater than the increase in the amount of peak ground accelerations.
703

Development Of A Subsidence Model For Cayirhan Coal Mine

Haciosmanoglu, Esenay Meryem 01 October 2004 (has links) (PDF)
In this study, subsidence analyses were carried out for panels B14, B12, B10, B02, C12, C10, C08 of &Ccedil / ayirhan Lignite Mine using in-situ subsidence measurements. Using the measurements from stations, installed both parallel and perpendicular to panel-advance direction, subsidence profiles were plotted as a function of time and distance from panel center. Horizontal displacement and strain curves were also plotted and compared with subsidence profiles. There are various methods used for subsidence prediction. In this study however, a subsidence model was developed based on empirical model obtained from nonlinear regression analysis. During the analyses SPSS (V.10.0) software was used and the unknown parameters associated with subsidence function were determined for the stations above B14 panel. Since it was too complicated to take all the affecting factors into consideration, only the parameters which could be estimated by statistical evaluation were taken into account during analyses. One significant contribution of this study to subsidence subject was the comparison of the subsidence values measured during this investigation with the values predicted by some other empirical methods. In this study, the structural damages to the pylons installed on ground surface above retreating longwall panels were also investigated by the use of previous studies. Slope as well as horizontal strain changes caused by ground movements due to underground mining were determined. Last but not least, it should be stated another significant contribution of this study to engineering was the collection of a significant database obtained from field measurements.
704

Nonlinear state-space control design for displacement-based real-time testing of structural systems

Moosavi Nanehkaran, Seyed Abdol Hadi 06 1900 (has links)
This study presents the nonlinear design of a state space controller to control hydraulic actuators under displacement control, specifically for real-time pseudo-dynamic testing applications. The proposed control design process uses the nonlinear state space model of the dynamics of the system to be controlled; and utilizes state feedback linearization through a transformation of the state variables. Comparisons of numerical simulation results for linear state-space and nonlinear state-space controllers are given. Also robustness of the control design with respect to identified parameters is investigated. It is shown that a controller with improved performance can be designed using nonlinear state space control design techniques, provided that a representative model of the system is available. / Structural Engineering
705

Load-displacement behavior of frame structures composed of fiber reinforced polymeric composite materials

Na, Gwang-Seok 17 November 2008 (has links)
This thesis addresses the results of an experimental and analytical investigation aimed at examining the static load-displacement response of braced plane frame structures composed of fiber reinforced polymeric (FRP) composite material structural members manufactured by the pultrusion process. In the experimental part of this investigation, eighteen full-scale lateral loading tests for FRP composite frames with different brace configurations and beam column connection types were performed. The load-displacement responses of such frames were measured and are reported herein. In the analytical part of this investigation, a frame analysis method that accounts for the anisotropic nature of FRP composite material structural members was investigated. The results from the experimental work are compared with the results from the analytical procedures. The effects of various structural parameters of the frame such as (1) effective mechanical material properties of members, (2) beam-column connection types, and (3) the influence of diagonal structural members on the lateral load-displacement response of the braced plane frames are also investigated. The numerical load-displacement results from the proposed FRP composite frames analysis procedure provided good agreement with the results from the full-scale laboratory tests.
706

Effect of valve replacement for aortic stenosis on ventricular function

Zhao, Ying January 2011 (has links)
Background:Aortic stenosis (AS) is the commonest valve disease in the West. Aortic valve replacement (AVR) remains the only available management for AS and results in improved symptoms and recovery of ventricular functions. In addition, it is well known that AVR results in disruption of LV function mainly in the form of reversal of septal motion as well as depression of right ventricular (RV) systolic function. The aim of this thesis was to study, in detail, the early and mid-term response of ventricular function to AVR procedures (surgical and TAVI) as well as post operative patients’ exercise capacity. Methods:We studied LV and RV function by Doppler echocardiography and speckle tracking echocardiography (STE) in the following 4 groups; (1) 30 severe AS patients (age 62±11 years, 19 male) with normal LV ejection fraction (EF) who underwent AVR, (2) 20 severe AS patients (age 79±6 years, 14 male) who underwent TAVI, (3) 30 healthy controls (age 63±11 years, 16 male), (4) 21 healthy controls (age 57±9 years, 14 male) who underwent exercise echocardiography. Results: After one week of TAVI, the septal radial motion and RV tricuspid annulus peak systolic excursion (TAPSE) were not different from before, while surgical AVR had significantly reversed septal radial motion and TAPSE dropped by 70% compared to before. The extent of the reversed septal motion correlated with that of TAPSE (r=0.78, p<0.001) in the patients as a whole after AVR and TAVI (Study I). Compared with controls, the LV twist function was increased in AS patients before and normalized after 6 months of surgical AVR. In controls, the LV twist correlated with LV fractional shortening (r=0.81, p<0.001), a relationship which became weak in patients before (r=0.52, p<0.01) and after AVR (r=0.34, p=ns) (Study II). After 6 months of surgical AVR, the reversed septal radial motion was still significantly lower than before. The septal peak displacement also decreased and its time became prolonged. In contrast, the LV lateral wall peak displacement increased and the time to peak displacement was early. The accentuated lateral wall peak displacement correlated with the septal peak displacement time delay (r=0.60, p<0.001) and septal-lateral time delay (r=0.64, p<0.001) (Study III). In 21 surgical AVR patients who performed exercise echocardiography, the LV function was normal at rest but different from controls with exercise. At peak exercise, oxygen consumption (pVO2) was lower in patients than controls. Although patients could achieve cardiac output (CO) and heart rate (HR) similar to controls at peak exercise, the LV systolic and early diastolic myocardial velocities and strain rate as well as their delta changes were significantly lower than controls. pVO2 correlated with peak exercise LV myocardial function in the patients group only, and the systolic global longitudinal strain rate (GLSRs) at peak exercise was the only independent predictor of pVO2 in multivariate regression analysis (p=0.03) (Study IV). Conclusion: Surgical AVR is an effective treatment for AS patients, but results in reversed septal radial motion and reduced TAPSE. The newly developed TAVI procedure maintains RV function which results in preservation of septal radial motion. In AS, the LV twist function is exaggerated, normalizes after AVR but loses its relationship with basal LV function. While the reversed septal motion results in decreased and delayed septal longitudinal displacement which is compensated for by the accentuated lateral wall displacement and the time early. These patients remain suffering from limited exercise capacity years after AVR.
707

Reinforcement and Sexual Selection: Interaction and Effect on Mate Recognition

Higgie, Megan Unknown Date (has links)
No description available.
708

The economics of managing congestion: with special reference to backcountry recreation

Kerr, Geoffrey N. January 1992 (has links)
The management of congestible recreation resources has been based largely on the concept of satisfaction. This concept is poorly defined and often does not reflect objectives for management of recreation resources. One way of addressing these problems is to define and use measurable objectives for management of recreation resources. One such objective is economic efficiency. The concept of efficiency is defined and economic theory developed to identify efficient allocations of congestible resources, the efficient capacities of resources under different allocation mechanisms, and the efficiency costs of use of lottery-based allocation mechanisms. The usefulness of this body of economic theory in allocation of backcountry recreational resources is addressed through investigation of ability to measure demand for congestible resources, and the problems associated with use of surrogate measures of demand. Theoretical models of efficient management of congestible resources cannot be applied with the current state of knowledge because existing non-market valuation methods are not able to identify Hicksian-compensated demand functions for congestible backcountry recreation. Use of Marshallian demand measures introduces the possibility of resource misallocations of unknown direction and magnitude.
709

The effect of partial-flow operation on the axial vibration of double-suction centrifugal pumps

Hodkiewicz, Melinda R. January 2005 (has links)
[Truncated abstract] Centrifugal pumps are designed to operate at a capacity that maximizes the efficiency of the pump. Operation below this design capacity results in reduction of pump efficiency as the geometric configuration of the impeller and casing no longer provide an ideal flow pattern. Consequently there are changes in the flow field within the pump, including flow separation and regions of localized, non-uniform, unsteady flow. This flow interacts with rotating and stationary components inside the pump creating additional disturbance and hydraulic excitation. It is anticipated that the local hydrodynamic and global hydroacoustic excitation due to partial-flow operation will affect the structural vibration measured on the pump. In this study, the effects of partial-flow operation on the vibration signal at the pump bearing housing are measured on a number of industrial double-suction pump units. These are a particular class of centrifugal pump commonly used in high volume applications such as water distribution. The aims are to understand how the vibration signals change at the different operating conditions and to determine which parameters are best suited to monitoring the observed changes. Comparison is made between the response, under similar operating conditions, of pumps both within sets of identical size and design, across sets of similar design and different sizes, and between different designs. The pumps are all in-service industrial units. In double-suction pumps the impeller motion in the axial direction (along the line of the shaft) is not constrained. Due to symmetry in impeller design, axial stability is maintained by equal and opposite hydraulic forces on the two opposing sides of the impeller. The potential for loss of axial hydraulic balance during partial-flow operation is examined from a theoretical perspective, based on a literature review, and by measurement of the axial displacement of the shaft. Structural vibration is measured using accelerometers mounted at the non-drive end bearing housing in the horizontal and axial orientations. Changes in signal contribution and characteristics are examined using a variety of qualitative and quantitative techniques. Test signals are used to assess the limitations of the techniques and the effect of parameter selection on the interpretation of the signals.
710

Cost-effectiveness of epidural steroid injections to treat lumbosacral radiculopathy in chronic pain patients managed under Workers' Compensation

Mohammed, Sheila. January 2008 (has links)
Thesis (M.S.P.H.)--University of South Florida, 2008. / Title from PDF of title page. Document formatted into pages; contains 45 pages. Includes bibliographical references.

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