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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.
231

SAT based environment for logical capacity evaluation of via configurable block templates

Dal Bem, Vinícius January 2016 (has links)
ASICs estruturados com leiautes regulares representam uma das soluções para a perda de rendimento de fabricação de circuitos integrados em tecnologias nanométricas causada pela distorção de fotolitografia. Um método de projeto de circuitos integrados ainda mais restritivo resulta em ASICs estruturados configuráveis apenas pelas camadas de vias, que são compostos pela repetição do mesmo modelo de bloco em todas as camadas do leiaute, exceto as camadas de vias. A escolha do modelo de bloco tem grande influência nas características do circuito final, criando a demanda por novas ferramentas de CAD que possam avaliar e comparar tais modelos em seus diversos aspectos. Esta tese descreve um ambiente de CAD baseado em SAT, capaz de avaliar o aspecto de capacidade lógica em padrões de blocos configuráveis por vias. O ambiente proposto é genérico, podendo tratar quaisquer padrões de bloco definido pelo usuário, e se comporta de maneira eficiente quando aplicado aos principais padrões já publicados na literatura. / Structured ASICs with regular layouts comprise a design-based solution for IC manufacturing yield loss in nanometer technologies caused by photolithography distortions. Via-configurable structured ASICs is even a more restrictive digital IC design method, based on the repetition of a block template comprising all layout layers except the vias one. The choice of such a design strategy impacts greatly the final circuit characteristics, arising the need for specific CAD tools to allow template evaluation and comparison in different aspects. This work presents a SAT-based CAD environment for evaluating the logical capacity aspect of via-configurable block templates. The proposed environment is able to support any user-defined template, and behaves efficiently when applied to block templates presented in related literature.
232

Sound Propagation Through Walls

Berglund, Alexander, Herbai, Fredrik, Wedén, Jonas January 2021 (has links)
Infrasound is undetectable by the human ear and excessive exposure may be a substantial health risk. Low frequency sound propagates through walls with minimal attenuation, making it difficult to avoid. This study interprets the results from both analytical calculations and simulations of pressure waves propagating through a wall in one dimension. The wall is thin compared to the wavelength; the model implements properties of three materials commonly used in walls. The results indicate that the geometry of the wall, most importantly the small ratio between wall width and wavelength, is the prime reason for the low levels of attenuation observed in transmitted amplitudes of low frequency sounds, and that damping is negligible for infrasound. Furthermore, a one-dimensional homogeneous wall model gives rise to periodicity in the transmitted amplitude, which is not observed in experiments. Future studies should prioritize the introduction of at least one more dimension to the model, to allow for variable angles of incidence.
233

Essays on Improving Access to Four-Year Colleges

Pippins, Theo January 2022 (has links)
This dissertation includes three essays that examine the potential of policies, interventions, and curricula in improving transitions to four-year colleges and universities in the U.S. The first essay provides a novel investigation of New York City’s adoption of SAT School Day (SSD), which provides universal access to college entrance exams for high school juniors. I examine the causal impact of the policy on SAT taking and four-year college enrollment patterns for the first three post-policy cohorts. Using a two-way fixed effects differences-in-differences (DID) model, I find that the SSD policy increases SAT-taking rates by 20% but has little impact on four-year enrollment. These findings suggest that increased college entrance test participation alone is not sufficient to increase enrollment to four-year colleges. The second essay provides a systematic review and meta-analysis of 19 studies on the causal impact of late pre-college advising interventions, which I refer to as LPCAIs. LPCAIs aim to connect juniors and seniors with pre-college advisors to guide them through the complex college application process. The studies use experimental and quasi-experimental designs to identify the causal effect of LPCAIs on postsecondary enrollment outcomes for historically underrepresented students. I find that the offer of an LPCAI, on average, increases postsecondary enrollment and improves institutional choices. However, the in-person advising format accounts for nearly all of the positive impact derived from LPCAIs. Several implications of these findings are discussed, particularly in the context of COVID-19. The third chapter presents a correlational study that uses transcript data from a statewide community college system to estimate how well GPA, credit accumulation, and course taking at community college predict upward transfer and baccalaureate completion. While GPAs and credit accumulation rates in all academic branches are strong, positive predictors of transfer, GPAs in humanities are significantly more predictive of transfer compared to GPAs in non-humanities branches. GPAs and successful credit accumulation rates in humanities courses are also associated with greater likelihoods of baccalaureate completion, conditional on transfer. However, humanities courses are equally valid predictors of baccalaureate completion as courses in other academic branches. In contrast to strong academic performance, taking more courses in humanities, although associated with greater likelihoods of vertical transfer, is associated with lower likelihoods of baccalaureate completion. Taken together, these essays contribute to our understanding of approaches to improve transitions to four-year colleges and universities. They also highlight the importance of academic preparation and advising within transitional pathways.
234

Stöld på arbetsplatsen. En kvantitativ studie av stöld som begås av anställda utifrån Situationella handlingsteorin

Grundberg, Clara, Ahlström, Fanny January 2015 (has links)
Den aktuella studien undersöker stöld som begås av anställda utifrån en kriminologisk teori som integrerar individuella och kontextuella faktorer – Situationella handlingsteorin. Syftet med studien är att testa huruvida denna teori utgör en lämplig förklaringsmodell för stöld som begås av anställda inom den svenska café- och restaurangbranschen samt detalj- och partihandeln. Studien ämnar även undersöka om individers stöldbenägenhet skiljer sig åt på respektive utanför arbetsplatsen. Studien grundar sig på primärdata inhämtad med hjälp av en webbenkät, distribuerad på det sociala nätverket Facebook. Materialet analyserades statistiskt och de huvudsakliga resultaten visar att individens benägenhet, i form av moral och självkontroll, samt motivation i form av frestelser, kan bekräftas som viktiga prediktorer för stöld som begås av anställda. Med grund i de samlade resultaten dras slutsatsen att Situationella handlingsteorin kan anses vara en lämplig förklaringsmodell för stöld på arbetsplatsen. / The present study examines theft committed by employees from a criminological theory, which integrates individual and contextual factors – Situational Action Theory. The purpose of this study is to test whether this theory is an appropriate model of explanation for theft committed by employees of the Swedish café and restaurant industry as well as retail and wholesale trade. The study also intends to examine whether individuals differ in their propensity to steal in, compared to outside of, their workplace. The study is based on primary data acquired with an online questionnaire, distributed on the social network Facebook. The material was analyzed statistically and the main results showed that individual's propensity, in the form of morality and self-control, and motivation in the form of temptations, can be confirmed as important predictors of theft committed by employees. With the foundation of the overall results the conclusion is that the Situational Action Theory could be considered a suitable model of explanation for theft in the workplace.
235

National Merit Finalists At The University Of Central Florida-trends, Attrition, And Retention 1997-2005

Norburn, Jill 01 January 2006 (has links)
The purpose of this study was to examine the trends, attrition and retention rates of National Merit Finalists at the University of Central Florida between the years of 1997 to 2005. This study was intended to provide information for higher education practitioners, faculty, and administrators to help them better understand the expectations and current trends of National Merit Finalists. The problem was to determine how to increase recruitment and retention while decreasing the attrition rates of these highly desirable students. The importance of this study includes identifying trends that may aid in future recruitment efforts for National Merit Finalists; finding the causes of dissatisfaction towards the University among these students; and identifying specific areas in which to alleviate those dissatisfactions. The results will hopefully provide insight into specific recruitment, services, and programming options for these students. The study examined data that was collected from the University of Central Florida's Burnett Honors College database known as FileMaker 8.0. The data examined characteristics such as grade point averages (high school and college); valedictorian and salutatorian status; test scores (SAT and ACT); Honors in the Major (undergraduate thesis) students; Honors and university status (withdrawn, probation, removed, disqualified, enrolled, graduated); Honors college attrition; university attrition; ethnicity; gender ratios; majors; and, prestigious scholarships awarded in college (such as the Rhodes, Truman, Marshall). The actual size of the sample was one hundred ninety-eight National Merit Finalists. Data was also collected from a survey given to all University of Central Florida National Merit Finalists. Descriptive statistics were reported for each of the components examined. This data examined the types of scholarship packages that National Merit Finalists were offered; the reasons students chose the University of Central Florida over other universities; the college recruitment process; hours studied for the PSAT; siblings; perceptions on being a National Merit Finalist; the number of times students changed their majors; job status; transportation; computer attainment; disabilities; and the potential disadvantages of being labeled as a National Merit Finalist. The data could be utilized to examine the trends of our National Merit Finalists, in order to see what is working and what is not in terms or recruitment and retention; and also to further examine what these students want from their institutions. Findings indicated that problems exist in regard to the following: the recruitment of female and minority National Merit Finalists; males historically score higher on the SAT than females; decreasing the attrition rates of this population at the University of Central Florida; the majority of National Merit Finalists at the University of Central Florida come from Florida; the majority of National Merit Finalists at the University of Central Florida do not tend to be high school salutatorians or valedictorians; high school counselors seem to be the least effective tool for recruiting National Merit Finalists at the University of Central Florida; and the majority of National Merit Finalists at the University of Central Florida did not study at all for the PSAT test. However, the University of Central Florida is extremely competitive with other institutions of higher education with regard to scholarship packages. Results also revealed the following: the SAT is a more widely accepted tool for determining NMSC status as opposed to the ACT; the majority of National Merit Finalists have a GPA between 3.600 and 3.999 at the University of Central Florida; the University of Central Florida is succeeding in making its National Merit Finalists feel special during the recruitment process; the most influential reason that National Merit Finalists are choosing UCF is based upon the financial scholarship packages they are offered; and the majority of National Merit Finalists at the University of Central Florida do not feel that there are disadvantages toward being labeled as such. This data provides a basis for further research on National Merit Finalists trends, attrition, and retention. Practical considerations are revealed in the data that will influence future recruitment methods and lead to higher retention rates and increased student satisfaction. Several other recommendations are made to conduct further research studies on the trends, attrition, and retention rates of National Merit Finalists.
236

La sátira política en <i>Fray Gerundio</i> (1837-1842) de Modesto Lafuente

Fuertes-Arboix, Monica 14 September 2006 (has links)
No description available.
237

Einfluss von Transforming Growth Factor - beta 1 (TGF-β1) und Hypoxie auf die Expression von Sulfattransportern (SAT-1 und NaSi-1) in den humanen renalen Zelllinien TK173 und TK188 / Influence of Transforming Growth Factor beta 1 (TGF-β1) and hypoxia on the expression of sulfate-transporters (SAT-1 and NaSi-1) in the human renal cell lines TK173 and TK188

von Fintel, Hendrik 10 October 2011 (has links)
No description available.
238

Využití termovizní kamery pro měření teploty elektrických strojů / Utilization of infrared camera for temperature measurement of electrical machines

Líbal, Jan January 2009 (has links)
The master‘s thesis deals with utilization of infrared camera for temperature measurement of electrical machines. The first part describes non-contact temperature measuring, the second part describes principle of sensors that evaluate quantity of incident infrared radiation. In the next part there is termovision camera SAT-HY 6800 presented and the instructional manual for SAT Report computer programme created. This computer programme is used for analyzing of termovision pictures from the SAT-HY 6800 termovison camera. The chapter 7 describes temperature measuring of one-phase asynchronous motor type J22TO484. The chapter 8 describes temperature measuring of semiconductor components of EC motor G6 series. Both of these motors are produced by ATAS elektromotory Náchod a.s. The last part of the thesis describes creation of animation of one-phase asynchronous motor type J22TO455. The animation was created in 3ds Max computer programme.
239

Etude de la diffusion réactive entre Mn et Ge à l'échelle nanométrique pour des applications en spintronique / Study of reactive diffusion between Mn and Ge at the nanoscale for spintronic applications

Abbes, Omar 28 February 2013 (has links)
Le couplage des propriétés ferromagnétiques et semiconductrices représente une perspective prometteuse, afin de réaliser des technologies qui exploitent le spin des électrons. Ceci permettra de stocker et traiter des bits informatiques de façon instantanée dans le même dispositif, plutôt que dans des dispositifs séparés (mémoire et processeur). La Spintronique pourrait alors révolutionner la technologie de l'information. Un candidat potentiel pour la fabrication d'hétérostructures métal ferromagnétique/semiconducteur pour des applications en Spintronique, est le système Mn-Ge. Ce système qui est compatible avec la technologie CMOS, présente une phase intéressante pour la Spintronique qui est Mn5Ge3, avec une possibilité d'épitaxie sur le Ge(111). Afin d'intégrer cette phase dans des procédés de fabrication, nous étudions la diffusion réactive à l'état solide entre un film de Mn et un substrat de Ge (comme dans le cas de la formation des siliciures dans la technologie CMOS). L'accent a été mis sur la séquence de formation de phases lors de la réaction entre un film nanométrique de Mn et le Ge, l'influence de l'interface sur cette réaction, et sur la diffusion du Mn dans le Ge. L'incorporation du carbone dans des films minces de Mn5Ge3 a montré une augmentation notable de la température de Curie : nous présentons alors l'effet du carbone sur la réaction Mn-Ge, et sa redistribution dans les couches minces MnxGey. / Coupling ferromagnetic and semi-conducting properties represents a pathway toward producing technologies that exploit the spin of electrons. That would allow store and process computer bits instantly in a same device, rather than separate devices (memory and CPU). The Spintronics could then revolutionize the information technology. A potential candidate for the fabrication of heterostructures ferromagnetic metal / semiconductor for Spintronics applications is the Mn-Ge system. This system is compatible with CMOS technology, and presents an interesting phase for Spintronics which is Mn5Ge3 phase, which is able to be grown epitaxially on Ge(111). To integrate this phase in the manufacturing process, we study the solid state reactive diffusion between a thin Mn film and Ge substrate, to form a germanide upon the Ge substrate (as in the case of the formation of silicides in CMOS technology). Emphasis was placed on the sequence of phase formation during the reaction between a 50 nm thick Mn film and Ge, the influence of the interface on the reaction, and the diffusion of Mn in Ge. Incorporation of carbon in thin Mn5Ge3 films showed a significant increase in the Curie temperature, we then present the effect of carbon on the reaction Mn-Ge and its redistribution in thin MnxGey films.
240

Summation By Parts Finite Difference Methods with Simultaneous Approximation Terms for the Heat Equation with Discontinuous Coefficients

Kåhlman, Niklas January 2019 (has links)
In this thesis we will investigate how the SBP-SAT finite difference method behave with and without an interface. As model problem, we consider the heat equation with piecewise constant coefficients. The thesis is split in two main parts. In the first part we look at the heat equation in one-dimension, and in the second part we expand the problem to a two-dimensional domain. We show how the SAT-parameters are chosen such that the scheme is dual consistent and stable. Then, we perform numerical experiments, now looking at the static case. In the one-dimensional case we see that the second order SBP-SAT method with an interface converge with an order of two, while the second order SBP-SAT method without an interface converge with an order of one.

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