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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.
111

Investigation and validation of vibratory methods for stress relieving and weld conditioning

Munsi, A. S. M. Younus January 1999 (has links)
Manufacturing processes inevitably induce a state of residual stress into materials and products. These residual stresses pose a large potential problem, in terms of dimensional stability and reduced fatigue life. Ideally, residual stresses should be reducible to low levels. There are three methods in general usage for the relaxation of these stresses, - Annealing, Shakedown and Vibratory Stress Relief (VSR). A previous study had suggested that vibration during and/or after welding may usefully modify residual stresses due to welding. This has been termed Vibratory Weld Conditioning (VWC). A comparative study of the methods is presented in section 1.4. The use of VSR, though widespread, has been adopted on a case-by-case basis, due to the lack of understanding of the processes at work. The purpose of this work was to investigate and validate the VSR/VWC method as a proposed alternative to the processes mentioned above. In order to do this a series of tests were devised in which the specimens were welded as a mechanism of stress induction. The residual stresses were measured before and after welding and vibration by means of a scanning X-ray diffractometer. In Chapter 1, the study of Residual Stress (source, formation etc), Welding Metallurgy and a comparison of VSR/VWC with other treatment methods are presented. In Chapter 2, a detailed review of literature is presented, where the accessible literature on VSR/VWC to date are included. In Chapter 3, the theoretical background of Modal Analysis, the Measurement of Dynamic Induced Stress and Measurement of Residual Stressesis discussed. In Chapter 4, the FE analysis of different structures is presented. In the FE analysis, different properties of the structures were determined using the FE model to aid the VSR/VWC study. The experimental investigations are presented in Chapter 5, which is divided into the following parts: Modal Analysis (experimental), Calibration of the X-ray measurements, VSR/VWC treatments, Cryogenic treatment, Fatigue Test and Metallurgical Investigation of VSR/VWC treated specimens. At the outset of the experimental work, the calibration of the X-ray diffractometer was carried out. After calibration of the X-ray and the X-ray Elastic Constant the error band of the diffractometer was significantly reduced. The practical modal analysis of the "8" frame was carried out to determine the modal characteristics of the frame to aid the VSR investigation of the frame. The VSR/VWC treatments are divided into "during welding" and "post weld" treatments and are presented in 10 different experiments. First, the "during welding" treatments were carried out. Investigation was started with application of tensile and compressive static stress to the specimens during welding and cooling. It was observed that the tensile induced stress decreased, and compressive induced stress increased the residual stresses. Rigid body motion (RBM) vibration showed no effect on the residual stresses. The cantilever beam test of the flexural vibration test showed some important characteristics, where the longitudinal residual stresses were found to decrease with application of small-induced stress. An increase in applied stress or time of vibration did not cause any more reduction. The transverse residual stresses increased with application of small-induced stresses. With increase in the applied stress the residual stresses decreased. High frequency vibration in both RBM and flexural vibration was found to be ineffective in reducing the residual stresses. The flexural vibration of the Four-Roller Supported beam showed a very confusing result, where no particular trend of the residual stresses was found. The combined mode of vibration (longitudinal and flexural) treatment showed no effect on residual stresses. The "post weld" treatment of the specimens showed a significant reduction in the residual stresses, where the reduction in the residual stresses were found to be a function of applied stress, while the vibration time effect was found to be negligible. A complex shape of reduction in the residual stresses were found along the width of the specimens, which made it impossible to develop any plastic flow model for the reduction in the residual stresses. Torsional test revealed a very important property of the residual stresses, where the residual stresses were found to decrease by a significant amount with application of very small induced stress. High induced stress only redistributed the residual stresses. Cryogenic treatment caused no reduction in the residual stresses. Contrarily the same specimen showed a significant reduction after VSR treatment. The fatigue test showed an increased fatigue life of the VSR treated specimens, while the thermally treated specimens showed a decreased fatigue life. The vibrated specimens showed highly oriented ferrite crystals in directions with Miller [111] to the stress axis. The hardness of the VSR treated specimens was found to increase significantly in comparison to the unvibrated specimens.
112

Court officers as certified first responders assisting in homeland security and community emergency preparedness

Williams, Jewel E. 06 1900 (has links)
CHDS State/Local / This thesis tests the proposition that training New York State Court Officers to be first responders will add needed resources to the emergency response capabilities of the court system and state and local homeland security. New York State Court Officers have been exposed to a number of terrorists' attacks, including the latest at the World Trade Center in September 2001. In the National Strategy for Homeland Security, it notes that even best-prepared states do not have an adequate amount of resources to respond to terrorist threats. The New York State Courts can add 3,700 new certified first responders an event that occurs in what is arguably the most likely target jurisdiction. The thesis shows that the added value of these officers on a state and local level would be extremely valuable. In light of this identified need for additional trained first responders, this thesis test the proposition that training these officers to become certified first responders will enhance and improve the number of available resources to respond to terrorist incidents. / First Deputy Chief, New York State (NYS) Courts
113

Optimized positioning of pre-disaster relief force and assets

Tean, Ee Shen. 12 1900 (has links)
Approved for public release; distribution is unlimited / Recent events in the United States of America and Pakistan have exposed the shortcomings of existing planning in relief and humanitarian assistance in the face of large-scale natural disasters. This thesis develops a two-stage stochastic optimization model to provide guidance in the pre-positioning of relief units and assets, where budget, physical limitations and logistics are taken into account. Stochastic data include the numbers of survivors in each potential affected area (AA), the amount of commodities that needs to be delivered to each AA and the transportation time from each relief location (which reflects sceanrios where, for example, roads are blocked). As first-stage decisions, we consider the expansion of warehouses, medical facilities and their health care personnel, as well as ramp space to facilitate aircraft supply of commodities to the AAs. The second-stage is a logistic problem respresented as a network, where maximizing expected rescued survivors and delivery of required commodities are the driving goals. This is accomplished through land, air and sea transportation means (e.g., CH-53 helicopters configured for rescue missions), as well as relief workers. The model has been successfully assessed on notional scenarios and is expected to be tested on realistic cases by personnel who are involved in relief planning. / Outstanding Thesis
114

Designing and prepositioning humanitarian assistance pack-up kits (HA PUKs) to support Pacific fleet emergency relief operations

McCall, Valerie M. 12 1900 (has links)
The 2006 Quadrennial Defense Review has emphasized the role of humanitarian assistance missions in winning the Global War on Terror. U.S. Pacific Fleet operates in an area prone to both terrorist recruitment and sudden-onset natural disasters that require humanitarian assistance and disaster relief operations. The U.S. Navy has unique capabilities to deliver first-response humanitarian assistance. This thesis develops and suggests prepositions for humanitarian assistance pack-up kits that contain emergency relief material commonly used in these missions in order to expedite delivery to those impacted by a disaster.
115

Perceived Stress and Coping Methods in Pharmacy Students

Acosta, Stefanie, Barnes, Valerie January 2010 (has links)
Class of 2010 Abstract / OBJECTIVES: To determine the perceived level of stress pharmacy students experience related to academics and the methods they use to relieve that stress. METHODS: This was a descriptive cross-­‐sectional study. Questionnaires were administered to first, second, and third year University of Arizona College of Pharmacy students during regularly scheduled class time. Data on perceived level of stress, sources of stress, and methods of relieving stress were collected and analyzed. Data on average hours worked per week, marital status, number of children, age, gender, and number of professional organizations involved in were also collected. RESULTS: The stress survey was completed by a total of 182 students at the College of Pharmacy. The overall stress score was highest in the second year students, although the total score was relatively low (total score 18.7; p=0.04). The four items that resulted in the highest stress scores were exams and/or grades (stress score ≥ 2.1), amount of class material (stress score ≥ 1.8), financial responsibilities (stress score ≥ 1.8) and lack of free time (stress score ≥ 1.6). Stressful situations that the students felt the most during the semester were thinking about the things that they had to accomplish (score ≥ 3.2) and having to control the way they spend their time (score ≥ 2.6). Common stress relievers were spending time with family, friends and pets ( ≥ 27%), watching television or movies ( ≥ 22%) and exercising ( ≥ 17%). Of those students who exercised, >44% felt it helped relieve stress very much. CONCLUSIONS: Little difference in levels of stress was observed between the classes. Based on the results, pharmacy students at the University of Arizona do not appear to be excessively stressed. Spending time with family/friends/pets, watching TV/DVDs, and exercising were the most common ways of relieving stress.
116

'Making ends meet' : working-class women's strategies against poverty in West Oxfordshire, c.1850-1900

Dubber, Melanie January 1997 (has links)
This thesis seeks to contribute to two areas of historical enquiry: the history of women and the history of poverty, by investigating the strategies used by women to cope with poverty. It attempts this in a systematic way by applying a taxonomy of strategies to the case study area of West Oxfordshire from the mid-to-late nineteenth century. As such, it broadens our understanding of the lives of women living in a rural area as well as examining poverty from the perspective of the responses to it. Three main strategies were considered; employment, household management and community strategies. General results of the analysis suggest that the strategic approach is a valuable method of examining the way poor rural women coped with poverty, highlighting the interconnections between their roles of reproduction, production and consumption. Specific results suggest that first, a radical rethink of the role and importance of the home as a female power base is required. Second, although strategies are difficult to quantify, certain strategies appear to have been more popular than others; household management emerged as the pivotal strategy to make ends meet. Careful spending and saving and the ability to utilise a variety of resouces such as animal husbandry and gardens and allotments was necessary in the fight against poverty. Employment, although of value, could not always be relied upon to provide a steady, regular income. Community strategies were of some value. They were provided informally by kin and the neighbourhood and formally by charities and poor relief. Third, certain factors were influential concerning the nature of strategies; namely duration of need, age and marital status, geographical location, seasonality and conditions for eligibility. The organic nature of the taxonomy means that it can be expanded to include additional strategies and used to study other groups of women such as the middle-class, different historical periods and geographical locations.
117

An approach to sustainable recovery of urban water supplies in war-affected areas : with specific reference to the Tuzla Region of Bosnia and Herzegovina

Ozerdem, Alpaslan January 1998 (has links)
No description available.
118

Is Debt Cancellation a Good Way to go?

Vopařilová, Radka January 2007 (has links)
The issue of the high levels of external debt in the poorest nations has become an increasing matter of concern for the industrialized nations due to the difficulties that heavily indebted nations have with sustaining economic growth. In 2005 the Group of Eight pledged to cancel the debt of the world?s most indebted countries that are eligible for the relief under the Highly Indebted Poor Country (HIPC) initiative. Based on this pledge, the World Bank and the International Monetary Fund approved the debt cancellation in March 2006, with debt cancellation commencing on June 1, 2006. As a reaction, this thesis provides an overview of arguments in favor of debt cancellation as well as against debt cancellation as they are introduced in economic literature. After presenting and taking all the points of view into consideration this thesis comes to the conclusion whether the debt cancellation is a good way to go.
119

Beyond the Minimum: A Durable Emergency Shelter

Child, Jason January 2013 (has links)
The number of states requiring humanitarian assistance after a disaster has doubled every decade since 1960. Extreme weather like flooding and violent storms associated with climate change are predicted to continue to increase with intensity and in frequency in the future. Traditionally, emergency shelters have been given in the form of two options: the tent or the tarp. While both do a great job at addressing immediate shelter needs, they are not durable enough habitations to provide adequate transitional shelter for the time period between six months and two years. Most emergency shelters provided by humanitarian agencies fail before six months. This thesis will investigate the development of an emergency shelter solution that improves upon the current options for affected regions following a disaster within warm climates. The thesis proposes that by employing more robust materials for emergency shelters the life expectancy can be extended to meet the required needs. Several materials and designs were explored, tested, and evaluated as plausible shelter solutions to accomplish this task. Design shapes including Roman and Gothic arches were tested with smoke simulations, wind load calculations, and continuous frame loading. The most successful design tested, the Roman arch, was then contrasted and compared to currently used disaster relief shelters for durability and cost. Thesis findings indicate that there is potential for economical and durable emergency shelter solutions. Further research on this topic will increase the number of shelter options available to humanitarian organizations in order to help both emergency and transitional shelter roles simultaneously.
120

Relief of the army - Morakot example

Chuang, chia-yin 04 July 2011 (has links)
In recent years, frequent global disasters such as Typhoon Morakot Republic of China 98 years with the 2011 earthquake in northeastern Japan, these disasters have caused the destruction of large-scale and large-scale, often the government or private relief organizations generally can not load capacity , to compensate for inadequate relief efficiency can be deployed quickly, efficiently support the government's disaster relief units and discipline, national army, police, the main consumer unit, and police units to maintain social order based, such as the main use for disaster relief, more not suitable, so the domestic disaster relief units, non-military, none other than the consumer unit, while the main army to fight, and its legitimacy in the context of this study, in the case of national disaster and emergency rescue shows that the military action in emergency relief and response play a very important role. Both discipline and efficiency not only for the organization, and disaster prevention and emergency response is to rescue the most important time, my country is satisfied that the military after the disaster since Typhoon Morakot one of the central task, while the military situation of disaster relief to the value created out of nothing. However, the national security and domestic disaster prevention organizations have not effectively integrated in the mechanism are also required to solve the problem, when disaster strikes, often severely affected by different levels of the efficiency of disaster relief. Therefore, this research study focused on the motive. The collate and analyze the U.S., Japan and the Chinese military system and the prevention of military, fire and victims of views, some suggestions are as follows: First, refer to the Japanese military relief and rescue regulations of the military situation for me complete relief laws; II to this new security and Taipei and Taichung million concentric drill, for example, development of military active duty, reserve and local governments have to develop mutual support of the relief plan with the annual military exercise, the norm of the exercise; Third, investment needs and national defense disaster training, raises the cost effectiveness of investment in national defense and disaster relief of the legitimacy of the military; Fourth, prevention must be added back to the mobilization and training facilities to meet the current social change. Need to continue to promote the future "sense of urgency of national defense establishment," "a complete disaster laws and regulations", "Construction of National Defense of the security system," the consensus. Basis should be established in future, committed to sophisticated, the forward-looking, overall, the reference approach the major advanced countries, to measure state conditions, a set of conditions for me really disaster prevention system in order to achieve "peace maintaining an army less military forces during the war and more "of the goal to meet the future needs of national defense, military disaster relief mission to reach.

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