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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.
101

Economic and Social Development of the Traditional Society: Studies of Ecuador, Turkey, and Vietnam

Corbin, Charles M. 01 May 1972 (has links)
No description available.
102

INCORPORATION OF LESS TOXIC ANTIFOULING COMPOUNDS INTO SILICONE COATINGS TO STUDY THEIR RELEASE BEHAVIORS

Al-Juhni, Abdulhadi A. 05 October 2006 (has links)
No description available.
103

Eliminating Redundant and Less-informative RSS News Articles Based on Word Similarity and A Fuzzy Equivalence Relation

Garcia, Ian 10 January 2007 (has links) (PDF)
The Internet has marked this era as the information age. There is no precedent in the amazing amount of information, especially network news, that can be accessed by Internet users these days. As a result, the problem of seeking information in online news articles is not the lack of them but being overwhelmed by them. This brings huge challenges regarding processing of online news feeds, i.e., how to determine which news article is important, how to determine the quality of each news article, and how to filter irrelevant and redundant information. In this thesis, we propose a method for filtering redundant and less-informative RSS news articles that solves the problem of excessive number of news feeds observed in RSS news aggregators. Our filtering approach measures similarity among RSS news entries by using the Fuzzy-Set Information Retrieval model and a fuzzy equivalent relation for computing word/sentence similarity to detect redundant and less-informative news articles.
104

Identifying Complex Fluvial Sandstone Reservoirs Using Core, Well Log, and 3D Seismic Data: Cretaceous Cedar Mountain and Dakota Formations, Southern Uinta Basin, Utah.

Hokanson, William H. 10 March 2011 (has links) (PDF)
The Cedar Mountain and Dakota Formations are significant gas producers in the southern Uinta Basin of Utah. To date, however, predicting the stratigraphic distribution and lateral extent of potential gas-bearing channel sandstone reservoirs in these fluvial units has proven difficult due to their complex architecture, and the limited spacing of wells in the region. A new strategy to correlate the Cedar Mountain and Dakota Formations has been developed using core, well-log, and 3D seismic data. The detailed stratigraphy and sedimentology of the interval were interpreted using descriptions of a near continuous core of the Dakota Formation from the study area. The gamma-ray and density-porosity log signatures of interpreted mud-dominated overbank, coal-bearing overbank, and channel sandstone intervals from the cored well were used to identify the same lithologies in nearby wells and correlate similar stratal packages across the study area. Data from three 3D seismic surveys covering approximately 140 mi2 (225 km2) of the study area were utilized to generate spectral decomposition, waveform classification, and percent less-than-threshold attributes of the Dakota-Cedar Mountain interval. These individual attributes were combined to create a composite attribute that was merged with interpreted lithological data from the well-log correlations. The overall process resulted in a high-resolution correlation of the Dakota-Cedar Mountain interval that permitted the identification and mapping of fluvial-channel reservoir fairways and channel belts throughout the study area. In the future, the strategy employed in this study may result in improved well-success rates in the southern Uinta Basin and assist in more detailed reconstructions of the Cedar Mountain and Dakota Formation depositional systems.
105

Portuguese as a Foreign Language: Motivations and Perceptions

Oliveira, Desiree 12 August 2011 (has links) (PDF)
Portuguese enrollments have been on a continuous rise at universities in the United States. Due to this increase it is important that teachers and department administrators understand what the motivations of Portuguese students are. This study reports on the findings of a survey conducted with lower-level Portuguese students at Brigham Young University regarding their motivations to study the language and compares these motivations with those of students of French, German, Italian, and Spanish. In addition, the study reports on students' perspectives on Portuguese in contrast to their perspectives on these other four European languages. Other issues considered include Portuguese students' native and foreign language backgrounds, their motivation to further pursue the study of Portuguese in the future, and their interest in two different varieties of the language, Brazilian and European Portuguese. Results revealed that only for Portuguese students were career plans the main motivation to study the language. Most Portuguese students already spoke Spanish fluently, either as a native or foreign language, and were also greatly motivated by the similarity between the two languages. Many Portuguese students were interested in pursuing their language studies in the future. Students reported being very interested in Brazilian Portuguese, but minimally interested in the European variety. Portuguese students' perceptions of the language were for the most part more positive than their perceptions of French, German, Italian, and Spanish, whereas non-Portuguese students' perceptions of Portuguese were mostly less positive than their perceptions of these other four European languages. Based on Portuguese and non-Portuguese students' responses to the survey questions, the study gives recommendations to promote the study of Portuguese as a foreign language at the post-secondary level.
106

Examining The Effect Of Organizational Policy Changeon Taser Utilizations

Miller, Michael 01 January 2008 (has links)
The purpose of this study is to examine the effect of organizational policy changes within the Use-of-Force Continuum on taser usage and officer's perceptions of taser effectiveness. Tasers have been used by police since the 1970s and their use is increasing as the technology has improved. Data reveals that tasers are beneficial for controlling non-compliant suspects while preventing serious injuries and rarely has their use resulted in death. Much of the public controversy surrounding tasers centers on when and how often officers deploy them. Use of force data from 890 police citizen encounters during a two-year period was analyzed to examine how changes in organizational policy have affected taser deployments and how policy changes have affected taser use. The study's findings support that after the policy change, the frequency of taser use by officers decreased, while the levels of suspect resistance encountered by officers increased. The frequency and severity of suspect injuries did not change and the numbers of officers injured in use-of-force encounters also did not change. Survey response data from officers were compared to archival data, which revealed that while officers perceive an increased risk of harm to themselves as a result of the organizational policy change that was not supported in the findings. Officers did not perceive an increased risk of harm to suspects which was supported in the archival data findings. Officers also expressed a belief that the organizational change that placed the taser at a higher level on the Use-of-Force Continuum is appropriate for most use-of-force encounters. This study concludes with future directions and trends for taser use in law enforcement.
107

Fabrication Refinements of Advanced Packaging Techniques for Medium-Voltage Wirebond-less Multi-Chip Power Modules

Lester, Danielle Kathryn 20 June 2023 (has links)
Three growing power electronics applications have massive requirements for properly operating their medium-voltage and high-voltage systems: electric transportation, renewable energy, and the power grid. Their needs include dense power systems with higher efficiency and higher voltage and current devices. This requires devices with higher switching frequencies to lower the size of the passives in the converter and devices that can withstand higher operating temperatures as components move closer together to improve power densities. Devices that achieve higher switching speeds and lower specific on-state resistances also reduce losses. Wide bandgap devices (WBG) like silicon carbide (SiC) have a higher bandgap, higher electric field strength, higher thermal conductivity, and lower carrier concentration than silicon (Si). This allows for higher temperature operation, faster switching, higher voltage blocking, and lower power losses, directly meeting the requirements of the previously noted applications. However, the current packaging schemes are limiting the ability of SiC to operate in these applications by applying packaging schemes used for Si. Therefore, it is critical to use and refine advanced packaging techniques so that WBG devices can better operate and meet the growing demands of these power electronic applications. Low-inductance, wirebond-less, high-density, scalable modules are possible due to advanced packaging methods. While beneficial to the operation and design, these techniques introduce new challenges to the fabrication process. This requires refinement to improve the yield of sandwich-structure modules with wirebond-less interconnects. For this module, encapsulated, silver-sintered substrates reduce the peak electric field within the package, improving the partial discharge inception voltage to meet insulation requirements. It is essential to have a uniform bondline between the substrates to achieve all bond connections and improve reliability. Silver sintering is also used to attach the molybdenum (Mo) post interconnects. These interconnects allow for sandwich-structure modules with low inductances; however, they have tolerance variation from manufacturing and bondline thicknesses, which become problematic for multi-chip power modules with an increased number of die and posts. The variation results in tilt, causing some posts to disconnect altogether. Additionally, soldering MCPMs involves a large thermal mass that the soldering reflow profile from a datasheet does not account for. Ultimately, these fabrication concerns can result in misalignment or disconnected post interconnects to the top substrate. Post interconnect planarity and alignment are vital for this multi-chip power module to avoid open or shorted connections that can derate switch positions. This thesis aims to refine each packaging step in assembling a wirebond-less, multi-chip power module. The bond uniformity of silver (Ag) sintering is addressed in dried preform and wet paste cases. The soldering methods are explored and improved by creating a modified reflow profile for large thermal masses and introducing pressure to reduce bondline variation and voiding content. The entire sandwich structure module is analyzed in a statistical tolerance analysis to understand which component introduces the most variation and height mismatch, providing insight as to which packaging techniques need further control to improve the yield of multi-chip power modules. / Master of Science / The electrification of many systems worldwide has increased the need for compact, efficient power electronics. Their applications span electric transportation, renewable energy systems, grid applications, and data centers, to name a few medium-voltage applications. Wide bandgap (WBG) semiconductors can outperform silicon in these applications, offering higher temperature robustness, higher efficiency performance, and higher voltage capabilities. The faster switching will reduce the size and weight of the converters containing these devices. However, using typical packaging schemes such as wirebonds will limit the potential of WBG devices in these applications. Advanced packaging techniques have been developed to increase the electric field strength, reduce the power loop inductances, reduce electromagnetic interference from fast-switching transients, and improve the power densities of multi-chip power modules for medium voltage and current applications. However, these packaging techniques are not trivial to implement and have resulted in a low yield of these modules. This thesis aims to refine each packaging step in assembling a wirebond-less, multi-chip power module. The bond uniformity of silver sintering is addressed in cases of dried preform and wet paste. The soldering methods are explored and improved by creating a modified reflow profile for large thermal masses and introducing pressure to reduce bondline variation and voiding content. The entire sandwich structure module is analyzed in a statistical tolerance analysis to understand which component introduces the most variation and height mismatch, providing insight as to which packaging techniques need further control to improve the yield of multi-chip power modules.
108

A study of factors that impact on executive network marketing in financial institutions in LDCs. An examination of factors that impact on executive network marketing in the finacial services sector in less developed countries: The case of Ghana.

Seddoh, Daniel K. January 2007 (has links)
This research study provides a view of the relationship between organizational leaders and relationship executives of financial institutions and their exchange partners. It does so by analyzing data on the networking efforts of 20 executive directors in qualitative interviews and 124 relationship executives in research questionnaires. Network marketing within the financial services sector is becoming increasingly important. We proposed a model that seeks to offer an explanation of Executive network marketing in financial institutions in LDCs where the market system is underdeveloped. The proposed model identified four categories being: firm characteristics, Executives’ personal contact groups, Executives’ business contact groups and issues of commitment and trust in exchange relationships. Multiple factor analysis established the regression model as significant in establishing a formal relationship between the dependent variable (network marketing) and the independent variables (firm characteristics, business contact, personal contact and commitment and trust). It was confirmed that there are differences in Executives’ level of network marketing among the different age groups. Also there were significant differences in the network marketing of the Executives with regard to their level of education. It was observed that there were significant differences in the network marketing of the Executives with respect of their fields of study. Finally it was observed that owner managers were more involved in network marketing than the professional managers and those in partnerships. Not only did the study confirm the research model, but it also revealed that, to a considerable extent, network marketing is practiced by the Executives in the financial services sector in Ghana. The study concluded that business contact networks are the most effective of the Executives’ network marketing in financial services sector in Ghana. It is therefore important that state policies are directed towards enhancing the business environment within the financial services sector. Government should desist from being a regulator and a player in the same market.
109

Left Ventricular Size and Outcomes in Patients With Left Ventricular Ejection Fraction Less Than 20% / 左室収縮率20%未満の患者での左室径と成績

Fukunaga, Naoto 23 January 2024 (has links)
京都大学 / 新制・論文博士 / 博士(医学) / 乙第13585号 / 論医博第2305号 / 新制||医||1070(附属図書館) / (主査)教授 石見 拓, 教授 古川 壽亮, 教授 近藤 尚己 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
110

Exploring Sedentary Time of Rural Children During Structured Versus Less-structured Days

Rayan, Serina 01 January 2020 (has links)
The purpose of this study is to examine rural children's sedentary time during school days vs non-school days Currently, childhood obesity research has focused predominantly on urban-dwelling children. However, existing literature indicates that rural children have higher rates of obesity than their urban counterparts. There is a current lack of evidence investigating the obesogenic behaviors of rural children, such as physical activity levels, sleep duration, sedentary behaviors and diet. With this project, I aim to observe sedentary time (time spent sitting, screen time etc.) as research has shown that independent of physical activity, sedentary time is associated with weight gain. A secondary aim of this research is to test the Structured Days Hypothesis which states that children engage in less-favorable obesogenic behaviors (e.g., prolonged sitting, higher screen time) during non-school versus school-days due to the removal of ‘structure' during non-school days.

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