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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.
51

Analysis of the energy savings gained by protective glazing on stained single-glass windows at Uppsala cathedral

Villaro, Izaskun January 2016 (has links)
Most European stained glass windows have no protection to reduce the damage due to environmental exposure, and this is the case of the great gothic windows in the Uppsala Cathedral. Currently, the implementation of protective glazing systems is being carried out in order to reduce the damage of the stained glass. In this connection, an analysis of the energy saving potential of the protective system is of great interest. The main obstacle in the implementation of this kind of systems is a social rejection based on the fact that the additional panes perturb the appearance of the historic building. Thus, demonstrating that there would actually be an energy saving, with the corresponding economic saving, would help approving the implementation of the protective glazing system. Measurement data needed for the analysis were available since they were used in condensation studies for the damaging analysis. However, the fact that this data was not gathered thinking of the energy saving analysis and its difficulties, some limitations have appeared in the present study. Accordingly, the needed simplifications imply some uncertainty in the results. However, the reliability of the results and the conclusions that can be drawn from the analysis are contrasted with previous similar studies. Different methods of calculation and analysis will be discussed, and finally results for the heat transfer coefficients through the open air gap and through the whole double paned system will be obtained. Furthermore, an energy saving analysis will be carried out with the winter data for both the case of the case of the Sonens fönster and the case of also implementing a similar system in the rosette of the cathedral. As a result, the conclusions drawn will be that the implemented protective glazing system reduces the heat losses through the windows to less than a third and that savings of about 8700 kWh/year and 13000 kWh/year are achieved in the case of the system being implemented only in Sonenes fönster and also in the rosette respectively. Finally, a rough study of the condensation problem will be exposed and possible matters, along with some advices, of further studies regarding more accurate analysis of both the condensation and the energy saving analysis will be presented. / Church project
52

Building cladding subject to explosive blast : a study of its resistance and survivability, with particular reference to architectural aspects and multi-panel glazing systems

El-Kadi, Abdul Wahab Mohamed Adel January 1998 (has links)
No description available.
53

An exploration of the socio-ecological antecedents of youth resilience : a visual study / Elaine Snyman

Snyman, Elaine January 2012 (has links)
The purpose of this study was to identify and understand the social-ecological resources which encouraged resilient Basotho youth in the rural areas of the Thabo Mofutsanyana district of the Free State province towards positive adjustment in the face of poverty and underdevelopment. Positive adjustment, or resilience, is the focus of the International Community-University Research Alliance (ICURA) and International Development Research Centre (IDRC) funded project, called Pathways to Resilience. My study forms part of this broader resilience study. Resilience, or positive adjustment to hardship, can be defined as the capacity of individuals to navigate their way to health-promoting resources that encourage positive adjustment, and the concomitant capacity of the individual’s family, community and culture to provide these health resources and experiences in culturally meaningful ways. Recently, researchers have suggested that the socio-ecological resources that encourage positive adjustment might differ across ecologies. There is little understanding in South Africa of which resources, within specific ecologies, encourage such positive adjustment. My study seeks to address this gap, with specific reference to Basotho youth in the Thabo Mofutsanyana district in the Free State. I used a qualitative phenomenological strategy of inquiry and participatory visual methods to determine the socio-ecological antecedents of the resilience of 130 resilient Basotho youth from rural areas of the Thabo Mofutsanyana district in the Free State province of South Africa. Using Bronfenbrenner‟s Ecological Systems Theory (1979), Sameroff‟s Transactional Model of Development (2009) and Unger’s Social Ecology of Resilience (2011) as framework, I explored the resources underpinning the resilience of my participants. The findings suggest that the resilient Basotho youth in this study were encouraged to adjust well to the risks of poverty and associated threats by making use of social-ecologically accessible resilience-promoting resources. In other words the resilient Basotho youth found resilience-promoting resources in their microsystems (individual, family, school, peers and nature and pets), mesosystems (social interactions), exosystems (community resources like libraries and medical facilities, and role models) and macrosystems (religious beliefs and practices, pastors, and access to information through television, radio, cell phone, and inspirational publications). The conclusion of my study lays emphasis on the interwovenness of socioecological systems in resilience processes: no one system could be sing led out. The entire ecosystem was involved, reciprocally, in providing the participants with resilience-promoting resources. My findings emphasise the importance of mothers, grandmothers, school and educational resources, religious beliefs and practices, and access to information (through the use of television, radio, computer and inspirational literature) for Basotho youth in the Thabo Mofutsanyana district, but do not suggest that these are the sole pathways to their resilience. Continued research in other parts of South Africa, with additional groups of youth, is needed to reach a comprehensive understanding of the socio-ecological antecedents of resilience among South African youth. / MEd, Learner support, North-West University, Vaal Triangle Campus, 2012
54

Evaluation of Law Enforcement and the Court System in Texas: Perspectives of Adult Protective Services Case Managers

Weaver, Matthew S. 05 1900 (has links)
The purpose of this study was to examine perceptions of Texas Adult Protective Services (APS) case managers (CM) in regard to their relationships with the law enforcement community and area courts. The sample consisted of 138 Texas APS CMs. The survey measured respondents' perceived strengths and weaknesses of their relationships with both the law enforcement community and with area courts. Items also included respondents' interest in receiving additional training and their perceptions of level of job-readiness of newly hired APS CMs. Data were analyzed quantitatively using SAS. Findings of the survey revealed high ratings of perceived teamwork on the part of the CM are associated with high relationship ratings with both area courts and law enforcement. Findings also revealed that high ratings of perceived autonomy on the part of the CM are associated with lower relationship ratings with law enforcement personnel but not with area courts.
55

An investigation into the relationship between resilience, protective factors and Posttraumatic Stress Disorder in a sample of psychology students at the University of the Western Cape

Neubert, Roxanne McLean January 2018 (has links)
Magister Artium (Psychology) - MA(Psych) / Due to the recent findings that the majority of South African’s have been exposed to high levels of trauma, the effects of trauma on mental health and wellbeing have become an important area of research in the South African context. Although many individuals in our country experience high exposure and multiple incidences of trauma, there are a significant number of people who seem to cope well in the face of adverse circumstances and trauma and do not develop stress symptomology as a result of exposure to a traumatic event. These individuals are viewed as resilient as they are able to utilize protective factors at their disposal, aiding them in preventing the development of symptoms associated with Posttraumatic Stress Disorder (PTSD). A large body of literature exists that identifies various protective factors, which may have a positive influence on an individual’s response to a traumatic event, thus making them more resilient. However, there is a gap in the South African research on the relationship between exposure to trauma, protective factors and the development of PTSD. The aim of this study is to explain how protective factors mediate PTSD symptoms. It investigates protective factors that resilient individuals utilize in the face of trauma such as; internal characteristics or traits, various demographic factors (i.e., age, gender), supportive interpersonal relationships, religious affiliation and community and family factors that have been identified as protective factors in the literature. Resilience emerged as significant in that it mitigated the development of posttraumatic symptoms (PTS) amongst the sample of university students. This indicates that despite the high incidences of exposure to trauma, individuals have the ability to be resilient, which therefore serves as a protective factor in the event of trauma. The present study constitutes a secondary analysis of previously collected survey data. The data being analysed is from a quantitative, cross-sectional survey that adopted a non-random, convenience sampling method. Logistic regression was undertaken in order to determine the relationship between age, religious affiliation, type of exposure, resilience and posttraumatic stress exposure. Only resilience emerges as a significant predictor underlying its importance for mediating traumatic outcomes. It highlights the importance od including protective factors in future research and interventions.
56

A study of respirator fit and face sizes of National Health Laboratory Service (NHLS) respirator users during 2013-2014

Manganyi, Mafanato Jeanneth 08 September 2015 (has links)
A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Public Health (Occupational Hygiene). Johannesburg, May 2015 / In the hierarchy of controls, the use of respirators is listed as the least preferable means of exposure or infection control; however it is often the primary means of protection in many industries including the health care industry. The National Health Laboratory Service (NHLS) provides diagnostic pathology laboratory services to the national and provincial health departments in nine South African Provinces. NHLS staff includes N95 respirator users working with infectious diseases such as tuberculosis (TB). It has been shown that an individual‟s facial structure influences their chances of achieving respirator fit. Study aim This study aims to describe the proportion of NHLS respirator users with adequate quantitative respirator fit while wearing their currently supplied respirators. Study objectives 1. To determine the proportion of NHLS respirator users achieving an adequate fit 2. To describe facial characteristics of NHLS respirator users and to group these faces into three face sizes (small, medium and large) based on the NIOSH fit test panel and two facial dimensions (face width and face length) 3. To explore the relationship between face size and demographic variables (sex, age, and race) of tested NHLS respirator users 4. To explore the influence of face size on respirator fit obtained by NHLS respirator users wearing their current respirator Materials and methods This was a cross sectional study with descriptive and analytical components. NHLS employees from selected laboratories in Gauteng, Cape Town and Durban were invited to participate. Study participants were respirator users and the majority were exposed to hazardous biological agents (HBA) including tuberculosis (TB). The NHLS employees included the four common South African race groups (as per Statistics South Africa) namely African, White, Coloured and Asian. A minimum sample size of 240 study participants was calculated for the study based on 30 participants per race group and sex. At the close of data collection 610 employees participated in this study. Quantitative respirator fit testing was conducted using a Portacount fit testing machine. Four facial dimensions were taken using callipers and a tape measure. STATA 12 was used to perform descriptive and interferential statistics. The associations between pass and fail and key predictors were investigated by chi-square tests. Student‟s t-tests and Kruskal-Wallis one way analysis of variance were used to investigate the overall fit factor in groups by face size, sex, race, age group and nose bridge width. The effect of the independent variables was explored using multiple linear regressions stratified by sex. Results and discussion Of the 610 employees who participated, a large percentage (78%) of NHLS respirator users failed fit testing and was not protected by their currently supplied medium size respirator. Ninety one percent of the respirators supplied were medium. The race group which achieved a highest proportion of fit factor passes was White (27%) followed by Africans (26%), a drop of pass rate was seen in Coloureds (21%) while the Asians achieved the lowest proportion at 7%. These poor pass rates indicate that a respiratory protection programme is needed in the NHLS, with focus on supplying the correct size and style of respirators. When the measured face length and face width of participants were plotted against the new bivariate NIOSH fit test panel, it was found that 35%, 58% and 7% of the participants had small, medium and large faces respectively. Our study population did fall within the panel but the distributions were different between cells compared to the American population. In the South African population Asians were more likely to be associated with a small face than Africans (p=0.00), Whites (p=0.00) and Coloureds (p= 0.00). While the Coloureds were not significantly different from the Whites or Africans (p= 0.397 p=0.713). The study showed that in addition to face length and face width, nose bridge width play a role in respirator fit. Multiple linear regression analysis showed that face size and nose bridge width were both significant predictors of overall fit. Although both sex and race predicted respirator fit in unadjusted analysis, these fell away when facial characteristic measurements were placed in the model. This suggests that sex and race maybe proxies for facial characteristics in predicting respirator fit. Conclusion and recommendation The high percentage of employees in this study sample achieving poor fit with their current respirator indicates a need for immediate testing of all NHLS respirator users and for a range of sizes and styles of respirators to be provided to all staff requiring respirators. The use of poorly fitting respirators could create a false impression of protection in the laboratories where employees are possibly exposed to HBA‟s including all types of TB. This also leads to in a large amount of funds being spent on purchasing ineffective respirators at the NHLS. A respiratory protection programme including respirator fit testing needs to be compiled, implemented and reviewed regularly to ensure sustainability. Future studies may include the investigation of the relevance of panels used in designing respirators to be worn by South Africans.
57

An evaluation of combined air-cooling and water-cooling for non-permeable clothing

Wang, I-Chung January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
58

study of protective coatings for NdFeB type permanent magnets =: NdFeB 型永久磁鐵的保護膜之硏究. / NdFeB 型永久磁鐵的保護膜之硏究 / The study of protective coatings for NdFeB type permanent magnets =: NdFeB xing yong jiu ci tie de bao hu mo zhi yan jiu. / NdFeB xing yong jiu ci tie de bao hu mo zhi yan jiu

January 1997 (has links)
by Ku, Nim Chung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references. / by Ku, Nim Chung. / Acknowledgment --- p.i / Abstract --- p.ii / Table of contents --- p.iv / List of figures --- p.viii / List of tables --- p.xiv / Chapter Chapter One --- Introduction / Chapter 1.1 --- History of permanent magnet materials --- p.1 / Chapter 1.2 --- NdFeB intermetallic compound --- p.4 / References --- p.8 / Chapter Chapter Two --- Background / Chapter 2.1 --- Corrosion and corrosion control --- p.9 / Chapter 2.1.1 --- Electrochemical mechanisms --- p.10 / Chapter 2.1.2 --- Types of corrosion cell --- p.12 / Chapter 2.1.3 --- Types of corrosion --- p.14 / Chapter 2.1.4 --- Corrosion control --- p.15 / Chapter 2.2 --- Intermetallic compounds and phases --- p.19 / References --- p.26 / Chapter Chapter Three --- Instrumentation / Chapter 3.1 --- Introduction --- p.27 / Chapter 3.2 --- Vacuum evaporator --- p.28 / Chapter 3.3 --- Vacuum furnace --- p.29 / Chapter 3.4 --- Scanning electron microscopy (SEM) & Energy dispersive analysis (EDX) --- p.29 / Chapter 3.5 --- Corrosion chamber --- p.31 / Chapter 3.6 --- Vibrating sample magnetometer (VSM) --- p.31 / References --- p.43 / Chapter Chapter Four --- Moisture corrosion test on a bare NdFeB permanent magnet (without any coating) / Chapter 4.1 --- Introduction --- p.44 / Chapter 4.2 --- Experimental procedures --- p.45 / Chapter 4.3 --- Results from visual inspection --- p.45 / Chapter 4.4 --- Corrosion behavior --- p.46 / Chapter 4.5 --- Measurement of the saturated magnetization --- p.47 / Chapter 4.6 --- The effect of corrosion on the magnetic property of the NdFeB magnet --- p.48 / Chapter 4.7 --- Conclusions --- p.49 / References --- p.57 / Chapter Chapter Five --- Interfacial reaction between the A1 coating and the NdFeB magnet / Chapter 5.1 --- Introduction --- p.58 / Chapter 5.2 --- Experiments --- p.59 / Chapter 5.3 --- The Interaction between the A1 coating and Magnet --- p.60 / Chapter 5.4 --- Conclusions --- p.63 / References --- p.67 / Chapter Chapter Six --- Corrosion behavior of A1 coated NdFeB magnet in moist environment / Chapter 6.1 --- Introduction --- p.68 / Chapter 6.2 --- Experiments --- p.69 / Chapter 6.3 --- Results --- p.69 / Chapter 6.3.1 --- The annealed samples before corrosion test --- p.70 / Chapter 6.3.2 --- Microstructure changes after 3 days of corrosion --- p.70 / Chapter 6.3.3 --- Corrosion process in the annealed samples --- p.71 / Chapter 6.4 --- Corrosion behavior --- p.73 / Chapter 6.4.1 --- Effects of NaCl on the samples --- p.73 / Chapter 6.4.2 --- Effects of the inter-diffusion --- p.74 / Chapter 6.5 --- Conclusions --- p.75 / References --- p.79 / Chapter Chapter Seven --- Dual layer coating of either Ti/Al or Ni/Al on the NdFeB permanent magnet / Chapter 7.1 --- Introduction --- p.80 / Chapter 7.2 --- Experiments --- p.81 / Chapter 7.3 --- The Interaction between the A1 and Magnet --- p.81 / Chapter 7.3.1. --- The Ti/Al coated magnets --- p.82 / Chapter 7.3.2. --- The Ni/Al coated magnets --- p.83 / Chapter 7.4 --- Volume contraction of the intermetallic coatings --- p.84 / Chapter 7.5 --- Conclusions --- p.85 / References --- p.90 / Chapter Chapter Eight --- Conclusions and suggestions for further studies --- p.91
59

Student Perceptions of Connectedness at the American International School of Utah

Johnson, Diane Longhurst 01 May 2019 (has links)
Connectedness has been identified as a powerful protective factor for adolescents. This study focused on the extent to which secondary students at the American International School of Utah (AISU) report perceptions of connectedness. Specifically, this work focused on school-level factors. It examined the extent to which participation in the school-wide interventions of Crew and Intensives influence perceptions of connectedness among AISU secondary students. Data collected provided insights about perceptions of connectedness within the AISU environment that may be used to inform current practices, identify additional student support needs, and improve future implementations. An Explanatory Sequential research design was used. This method included the use of quantitative measure administered and analyzed first, followed by a qualitative measure used to learn more about the quantitative results. The Hemingway Measure of Adolescent Connectedness Short Form by Michael Karcher served as the quantitative measure for this study. A semistructured interview protocol, created by the researcher, was used as the qualitative instrument. Results indicated that overall, study participants reported high-levels of connectedness on the Hemingway. Analysis of the Hemingway Subscales revealed that the Friends subscale had the highest levels of connectedness, followed by connectedness to Teacher. Connectedness to School was slightly lower than connectedness to Teachers. Connectedness to Peers showed moderate levels of connectedness. To learn more about the results of the quantitative stage of this study, semistructured interviews were conducted and analyzed using traditional deductive coding techniques. Results showed high-levels of connectedness associated with AISU as a school and with participation in Crew. Findings on the questions asking about Intensives showed that students appear to value the unique learning opportunities and ability to choose what they learn, more than they associated Intensives with connectedness.
60

Novel strategies for surface micromachining TiN thin films deposited by filtered arc

Dowling, Andrew John, andrewjohn3055@yahoo.com January 2005 (has links)
TiN is used commercially as a wear resistant coating on cutting tools and as a diffusion barrier in microelectronics. TiN has gained increased interest as a material for MEMS, however there has been very little work carried out in the area of patterning and releasing TiN for use as a structural MEMS material. This thesis presents an investigation into the patterning and release of filtered arc deposited TiN thin films using surface micromachining techniques. Two novel strategies are presented for patterning TiN thin films and are achieved using excimer laser micromachining and photolithographic wet-etching. TiN was deposited onto single crystal Si and Cr and Cu sacrificial layers on Si. The use of Cr as a sacrificial layer was found to facilitate the best quality patterning of the TiN and hence the majority of the work involved using Cr sacrificial layers. TiN was deposited using partial filtration and full filtration and differences in the ability to selectively laser pattern the TiN from the Cr sacrificial layer are presented. Various analytical techniques were employed to investigate the origin of the difference in laser patterning the TiN thin films. The establishment of TiN and Cr as a novel material combination for surface micromachined MEMS was extended by etching the Cr sacrificial layer to facilitate the release of TiN stress-measurement structures. The major finding of this thesis is that filtered arc deposited TiN thin film on Cr can be used as a material combination to surface micromachine freestanding TiN structures as high quality patterning and etch selectivity can be achieved using both excimer laser micromachining and photolithographic wet-etching.

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