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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.
271

Level Set Projection Method for Incompressible Navier-Stokes on Arbitrary Boundaries

Williams-Rioux, Bertrand 12 January 2012 (has links)
Second order level set projection method for incompressible Navier-Stokes equations is proposed to solve flow around arbitrary geometries. We used rectilinear grid with collocated cell centered velocity and pressure. An explicit Godunov procedure is used to address the nonlinear advection terms, and an implicit Crank-Nicholson method to update viscous effects. An approximate pressure projection is implemented at the end of the time stepping using multigrid as a conventional fast iterative method. The level set method developed by Osher and Sethian [17] is implemented to address real momentum and pressure boundary conditions by the advection of a distance function, as proposed by Aslam [3]. Numerical results for the Strouhal number and drag coefficients validated the model with good accuracy for flow over a cylinder in the parallel shedding regime (47 < Re < 180). Simulations for an array of cylinders and an oscillating cylinder were performed, with the latter demonstrating our methods ability to handle dynamic boundary conditions.
272

Essential Competencies for Entry-Level Management Positions in the Food and Beverage Industry in Taiwan and Mainland China

Huang, Tai-Yi 08 1900 (has links)
The purpose of this study was to identify the essential competencies for entry-level management positions in the food and beverage (F&B) industry based on the perspectives of Taiwanese industry professionals across three groups: work experience in Taiwan and/or mainland China, two F&B sectors (Hotel F&Bs and restaurants), and three management levels (first-line, middle, and top). A total of 515 Taiwanese F&B industry professionals participated in this study with 104 participants currently employed in mainland China, some of whom worked previously in Taiwan, and 411 participants working in Taiwan, without work experience in mainland China. Factor analysis produced four dimensions of important competencies: leadership, F&B management, interpersonal skills, and communication skills. Results indicated that communication skills was the only dimension that showed significant difference between participants with and without work experience in mainland China. The findings of this study indicated that 14 of 41 competency items were ranked in the top 10 based on the responses of the three groups. Participants from all three groups ranked "high level of personal integrity" as the most important competence and "ability to communicate orally in proper English" was ranked as the second most important competence by all groups except the restaurant sector. The results also showed that 10 of 41 competency items were ranked differently between participants with and without working experiences in mainland China. Findings are beneficial for graduates preparing to enter a management position in F&B, industry leaders/managers, recruiters and corporate trainers, educators, and future research.
273

Smoking and Cerebrovascular Disease: A Three-phase Research Program

Edjoc, Rojiemiahd January 2013 (has links)
Purpose: The purpose of this research program was three-fold. First it aimed to determine the effectiveness of smoking cessation interventions in increasing cessation rates in smokers with cerebrovascular disease and whether smoking cessation reduces stroke recurrence. Second it aimed to determine the prognostic influence of smoking and its association with stroke severity, disability, length of stay in hospital and mortality. Third it aimed to identify multi-level correlates of smoking cessation in Canadians who reported stroke symptoms in a large population based survey. Methods: Two systematic reviews and meta-analyses were performed to achieve the first objective. For the second objective, a retrospective cohort study was undertaken using variables from the Registry of the Canadian Stroke Network. Finally, the third objective was achieved by analyzing respondents from the Canadian Community Health Survey. Results: There is a paucity of intervention studies examining the effectiveness of smoking cessation in smokers with cerebrovascular disease. Most intervention studies that were found, failed to employ evidence-based approaches to smoking cessation. No evidence was found in regards to the effect of smoking cessation on stroke recurrence. We found smokers had strokes at a younger age compared to non-smokers. We found that in transient ischemic attacks and intracerbral haemorrhage, smoking was a significant predictor of stroke severity, disability, length of stay in hospital and 1 year mortality. Correlates of smoking cessation among Canadians who have experienced symptoms of a stroke included: higher education and income, implementation of household and vehicle smoking restrictions, access to a general practitioner and the use of smoking cessation pharmacotherapies and counselling support. Co-morbidities such as depression and alcohol consumption reduced the likelihood of successful cessation. Conclusions: This three-phase research program elucidated the gaps in intervention research for this population along with co-morbidities that hinder success in cessation. Smoking negatively impacted outcomes such as disability, hospital length of stay and mortality in patients with transient ischemic attacks and intracerebral haemorrhage strokes. Future interventions should take into account modifiable smoking cessation correlates in order to increase cessation rates in smokers with cerebrovascular disease.
274

On the horizon: Creating a contextual refuge on the shifting Louisiana coast

January 2014 (has links)
Climate change and sea level rise are making it more dangerous to live in coastal towns and cities. Communities in these areas must learn how to become more disaster resilient and adaptive by creating more connected and educated populations. In places devastated by natural disasters, the most vulnerable populations are the ones who are left behind. Climate refuges will become more and more common as people are forced to move from the places they call home due to inhabitable conditions. It would be beneficial for these populations to move before a large scale disaster forces them to leave. As the Louisiana coast subsides and is flooded by rising sea levels, the area is becoming more vulnerable to intense floods and storms. While there is a levee surrounding the New Orleans metropolitan area, the communities outside of the levee's protection are exposed to the elements. In these neighborhoods, the frequent damage by storms and rising flood insurance rates are making it too expensive to stay. St. Bernard and Plaquemines parishes are the areas that will lose the most land and where the land is vital to the local and national economy. An environmentally and contextually sensitive infrastructure will initiate the relocation of these populations, allowing them to remain in their communities while preserving their lifestyle and quality of life. To combat the dispersion of a strong community, I propose a system that allows the communities outside the levee walls to form new town centers within the flood protection. Specifically in St. Bernard Parish, a central hub would be built on the edge of the levee protection to attract people to move to a safer area. The town center is near the most southeastern part if the levee along Louisiana 46. The center will provide support for the intended increase in population as the area fills in with relocating residents. The center will increase the disaster resilience by providing spaces that can educate the public about climate change, facilitating movement to outside the levee with a boat and automobile transit hub, provide economic support through agriculture and fishing, and help the elderly population stay connected with their community. With the creation of this new town center, the residents that are threatened with sea level rise and flooding will be able to remain connected to their land, their communities, and their livelihoods while reducing their risk. / 0 / SPK / specialcollections@tulane.edu
275

Resiliency revised: Remediation and recreation in New Orleans water systems

January 2016 (has links)
In environmental terms, New Orleans is a city that should not exist. With the Mississippi River eager to escape its engineered confinement, the topography of the city sinking slowly due to subsidence, and the steady rise of sea level partnered with wetland and coastal erosion, the future of New Orleans is wet and it is fast approaching. Initial settlers built on the naturally elevated sediment deposits of the Mississippi River, but over time and as the city grew, swamps were drained and occupation spread into lower, more saturated ground. For over two hundred years, humans have interfered with water's natural authority over this area. We have contained, diverted, drained, and regulated rivers, lakes, and swamps to maintain a constructed version of the ground plane that subverts natural processes to the regions' detriment. Plans for the future of New Orleans have been debated since Hurricane Katrina served as an expose to our synthesized and extremely fragile system. From the Dutch Dialogues, a comprehensive u an redevelopment plan, to smaller scale water management studies such as the Mirabeau Water Gardens, the drawing board has rarely been empty. Proposals have met resistance from the community, and ten years after the disaster, no coherent plan has been outlined. New Orleans isn't the only city searching for answers; delta and coastal cities the world over are recognizing the need to rethink resiliency and sustainability in light of global environmental changes. This project proposes neighborhood-scale interventions that bring previously concealed water processes to light by exhibiting them in a sustainable community-centered resource. Rather than altering existing infrastructure, this strategy would utilize current neutral ground conditions in order to take pressure off the City's drainage network. By accepting and accommodating water within the urban fabric, New Orleans can address the deficiencies in defensive water infrastructure to define a new resilience. / 0 / SPK / specialcollections@tulane.edu
276

Segmentace ultrazvukových sekvencí / Ultrasound Image Sequences Segmentation

Kořínek, Peter January 2011 (has links)
When we scan image data by ultrasound, we have a little information of displayed scene. For understanding content of the image we try to separate the observed objects of interest from the background. Obtaining information of these objects is called a process called segmentation. This work is focused on the segmentation of ultrasound image sequences using geometric active contours solved by the method of level sets. For better representation is also dealing with image preprocessing. The result is an implementation of segmentation methods on simulated and real data.
277

Nízkoúrovňového měření ELF magnetických polí / Low-level measurement of ELF magnetic fields

Cích, Augustín January 2021 (has links)
This Master's thesis deals with design of sensor network for synchronised low-level recording of changes in magnetic part of Earth's field in ELF band in multiple places. The goal is acquisition of changes due to solar storm activity, while taking into account, that in research of geomagnetic effects connected with solar events is spectrum of interest broader and reach up to VLF, where a solution is often made of combination of receivers in ELF and VLF, a decision was made, after consulting with thesis supervisor and researchers, that device will be designed for ELF, but can be easily modified, by changing preamplifier, for using in higher frequency bands, creating a solid founding for further measurements and research in this field.
278

The Role of the County Emergency Manager in Disaster Mitigation

Savitt, Amanda Miller January 2020 (has links)
Scholarship on disasters in the United States would suggest that emergency managers should play a role in hazard mitigation. Yet, little empirical research has investigated precisely what role or roles emergency managers actually do play during this phase. This study explored the role of county-level emergency managers in hazard mitigation and the factors that might influence those roles. Data for this study was collected through 42 in-depth, telephone interviews with county- level emergency managers in FEMA Regions III, V, and X, which includes the Mid-Atlantic, Midwest, and Pacific Northwest regions of the United States. Grounded theory was utilized in order to organize and analyze the data. The data suggests that emergency managers play several roles within mitigation: a generic role, a support role, an administrative role, a promoter role, a public educator role, and a planning role. These roles are explained by a number of factors, including conceptual confusion, response and preparedness orientation, financial resource factors, planning factors, additional resource factors, competition between mitigation and development, resistance to mitigation, and engagement in mitigation. It is also important to note that emergency managers spend only a small amount of their time in mitigation. The results of this study suggest that there is a gap between the theorized role and the actual role that emergency managers play within mitigation. Closing this gap will likely require additional resources for mitigation and county-level emergency management, as well as greater consistency in defining mitigation through policy and education.
279

Motivational and Adaptational Factors of Successful Women Engineers

Bornsen, Susan Edith January 2012 (has links)
It is no surprise that there is a shortage of women engineers. The reasons for the shortage have been researched and discussed in myriad papers, and suggestions for improvement continue to evolve. However, there are few studies that have specifically identified the positive aspects that attract women to engineering and keep them actively engaged in the field. This paper examines how women engineers view their education, their work, and their motivation to remain in the field. A qualitative research design was used to understand the motivation and adaptability factors women use to support their decision to major in engineering and stay in the engineering profession. Women engineers were interviewed using broad questions about motivation and adaptability. Interviews were transcribed and coded, looking for common threads of factors that suggest not only why women engineers persist in the field, but also how they thrive. Findings focus on the experiences, insights, and meaning of women interviewed. A grounded theory approach was used to describe the success factors found in practicing women engineers. The study found categories of attraction to the field, learning environment, motivation and adaptability. Sub-categories of motivation are intrinsic motivational factors such as the desire to make a difference, as well as extrinsic factors such as having an income that allows the kind of lifestyle that supports the family. Women engineers are comfortable with and enjoy working with male peers and when barriers arise, women learn to adapt in the male dominated field. Adaptability was indicated in areas of gender, culture, and communication. Women found strength in the ability to ‘read’ their clients, and provide insight to their teams. Sufficient knowledge from the field advances theory and offers strategies to programs for administrators and faculty of schools of engineering as well as engineering firms, who have interest in recruitment, and retention of female students. Future research includes expanding the research to other areas of the United States, and improving engineering education pedagogy with more active and experiential learning.
280

Analýza vnitřního hluku vozidel a jeho vliv na aktivní bezpečnost / Analysis of Internal Vehicle Noise and its Influence on Active Safety

Dolejský, Lukáš January 2013 (has links)
Thesis is focused on the impact of the inside noise of the car on conditional driver safety, which is presented by reaction times on simulated stimulus. In introduction, there is a theoretical definition of the security of the vehicles, inside noise, and its methods of measurement. Practical part consists of description and realization of the measurements of the impact on the inside noise in the car on reaction time of drivers. Conclusion includes evaluations of the measurements and findings, which results from them.

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