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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.
151

On the design of HF radio modems / Timothy C. Giles.

Giles, Timothy C. January 1995 (has links)
Copies of author's previously published articles inserted. / Bibliography: leaves 118-126. / 160 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The subject of this thesis is the improvement of the design of High fidelity (HF) Radio modems by interpreting the high fidelity radio channel from a signal design perspective. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 1996?
152

Fatores da satisfa??o, fidelidade e recomenda??o em servi?o de sa?de: estudo em setor ambulatorial de hospital / Factors affecting satisfaction, loyalty and recommendation in health care: a study on a hospital ambulatory sector

Silva, Arivalda Bezerra da 09 September 2009 (has links)
Made available in DSpace on 2014-12-17T14:52:40Z (GMT). No. of bitstreams: 1 ArivaldaBS.pdf: 1467380 bytes, checksum: 1d741a3e11e90e76ab7729e977ec4cb8 (MD5) Previous issue date: 2009-09-09 / This thesis deals with the factors affecting customer satisfaction, loyalty and recommendation in the health care sector. It is adapted a model proposed by Johnson et al. (2001) of quality and loyalty antecedent factors and it is conducted a survey with a sample of 109 customers of a hospital on the ambulatory in Natal city, a capital of a Northeastern State of Brazil. It is carried descriptive and multiple regression statistical analysis. The main findings related to satisfaction are that quality factors of doctor professionalism, clerical staff efficiency, consultancy room comfort, time to provide the medical consultancy but also hospital localization are the most significant factors affecting satisfaction. Regarding personal full loyalty, satisfaction with the hospital and affective commitment are the main factors yet for partial loyalty image and calculate commitment play the main role. For recommendation satisfaction, image and brand are the main factors. The overall model used fairly explains the satisfaction, loyalty and recommendation outcomes with varying factors regarding each final purpose, e.g. loyalty or recommendation / Esta Tese de Mestrado investiga os fatores que afetam a satisfa??o, a fidelidade e a recomenda??o de clientes no setor de servi?os de sa?de. Utiliza-se um modelo estrutural baseado no modelo proposto por Johnson et al. (2001) contendo fatores antecedentes da satisfa??o e da fidelidade/ recomenda??o. A pesquisa consiste em question?rios com vari?veis e escala de 10 pontos aplicados a uma amostra de 109 pacientes de ambulat?rio de hospital em Natal-RN. Conduz-se uma an?lise descritiva e multivariada, usando-se an?lise de regress?o m?ltipla para cada vari?vel dependente satisfa??o, fidelidade, recomenda??o. Os principais achados relacionados ? satisfa??o s?o que os fatores de qualidade de profissionalismo dos m?dicos, efici?ncia dos funcion?rios, conforto da sala de consulta, al?m de outros fatores como tempo para o atendimento e localiza??o do hospital, foram os mais significativos. Em rela??o ? fidelidade pessoal, os fatores mais significativos foram satisfa??o com o hospital ou funcion?rios e comprometimento afetivo com o hospital. Para recomenda??o, apareceram como os principais fatores satisfa??o, imagem e marca. O modelo geral usado explica satisfatoriamente os resultados de satisfa??o, fidelidade e recomenda??o, com fatores diferentes para fidelidade e recomenda??o
153

Fatores que afetam a satisfa??o e a fidelidade do consumidor: um estudo com usu?rios de cal?ado esportivo (t?nis), na Regi?o Sul da cidade de Natal / Factors tht affect the consumer satisfaction and loyalty: a study with users o sport shoes (tennis), in the region southern city of Natal

Feij?, Thatiane Fernandes de Melo 29 October 2008 (has links)
Made available in DSpace on 2014-12-17T14:52:42Z (GMT). No. of bitstreams: 1 ThatianeFMF_pre_textuais_ate_cap5.pdf: 930085 bytes, checksum: 345c675cc181764d147fabbc57705cf4 (MD5) Previous issue date: 2008-10-29 / This paper aims to investigate the factors that influence the satisfaction and fidelity of tennis?s users with the region southern city of Natal, capital of Rio Grande do Norte as the area of analyzing , using the national satisfaction index models as a tool to study. In this study was used the questionnaire as a tool for collecting data based on the new Norwegian customer satisfaction barometer model proposed by Johnson et. al. (2001). The data collection took place during the months of May and June 2008, when 450 tennis?s users were interviewed. The main results obtained by multiple regression analysis and logistic regression showed that the users' satisfaction with the tennis?s brand is influenced by the quality, comfort, material used in the manufacture and price, while fidelity is potentized by the image of the brand and the satisfaction degree with the user's tennis and with the brand of tennis. In relation to user satisfaction with the tennis, that satisfaction is influenced by the quality, comfort, weight and the material used, while fidelity is potentized by the satisfaction with the tennis?s brand, with the possibility of paying the same amount again and the emotional commitment. As the processing of claims there was no direct influence on satisfaction and consumers fidelity due to the low number complaints / Este trabalho tem como objetivo investigar os fatores que influenciam a satisfa??o e a fideliza??o dos usu?rios de t?nis tendo como ?rea de analise a regi?o sul da cidade de Natal, capital do Rio Grande do Norte, utilizando-se como ferramenta de estudo os modelos nacionais de ?ndice de satisfa??o. No presente trabalho foi utilizado o question?rio como instrumento de coletas de dados baseado no novo modelo Noruegu?s proposto por Johnson et. al. (2001). A coleta de dados ocorreu durante o m?s de maio e junho de 2008, onde foram entrevistados 450 usu?rios de t?nis. Os principais resultados obtidos pela regress?o linear m?ltipla e pela regress?o log?stica, revelam que, a satisfa??o dos usu?rios com a marca do t?nis ? influenciada pela qualidade, conforto, material utilizado na fabrica??o e pelo pre?o, enquanto que a fidelidade ? potencializada pela imagem da marca e pelo grau de satisfa??o do usu?rio com o t?nis e com a marca do t?nis. J? com rela??o ? satisfa??o dos usu?rios com o t?nis, esta satisfa??o ? influenciada pela qualidade, conforto, peso do t?nis e material utilizado, enquanto que a fidelidade ? potencializada pela satisfa??o com a marca do t?nis, com a possibilidade de pagar novamente o mesmo valor e pelo compromisso afetivo. Quanto ao tratamento de reclama??es verificou-se n?o haver influencia direta na satisfa??o e fideliza??o do consumidor devido ao baixo n?mero reclama??es
154

Utilisation de simulateurs multi-fidélité pour les études d'incertitudes dans les codes de caclul / Assessment of uncertainty in computer experiments when working with multifidelity simulators.

Zertuche, Federico 08 October 2015 (has links)
Les simulations par ordinateur sont un outil de grande importance pour les mathématiciens appliqués et les ingénieurs. Elles sont devenues plus précises mais aussi plus compliquées. Tellement compliquées, que le temps de lancement par calcul est prohibitif. Donc, plusieurs aspects de ces simulations sont mal compris. Par exemple, souvent ces simulations dépendent des paramètres qu'ont une valeur inconnue.Un metamodèle est une reconstruction de la simulation. Il produit des réponses proches à celles de la simulation avec un temps de calcul très réduit. Avec ce metamodèle il est possible d'étudier certains aspects de la simulation. Il est construit avec peu de données et son objectif est de remplacer la simulation originale.Ce travail est concerné avec la construction des metamodèles dans un cadre particulier appelé multi-fidélité. En multi-fidélité, le metamodèle est construit à partir des données produites par une simulation objective et des données qu'ont une relation avec cette simulation. Ces données approximées peuvent être générés par des versions dégradées de la simulation ; par des anciennes versions qu'ont été largement étudiées ou par une autre simulation dans laquelle une partie de la description est simplifiée.En apprenant la différence entre les données il est possible d'incorporer l'information approximée et ce ci peut nous conduire vers un metamodèle amélioré. Deux approches pour atteindre ce but sont décrites dans ce manuscrit : la première est basée sur des modèles avec des processus gaussiens et la seconde sur une décomposition à base d'ondelettes. La première montre qu'en estimant la relation il est possible d'incorporer des données qui n'ont pas de valeur autrement. Dans la seconde, les données sont ajoutées de façon adaptative pour améliorer le metamodèle.L'objet de ce travail est d'améliorer notre compréhension sur comment incorporer des données approximées pour produire des metamodèles plus précis. Travailler avec un metamodèle multi-fidélité nous aide à comprendre en détail ces éléments. A la fin une image globale des parties qui forment ce metamodèle commence à s'esquisser : les relations et différences entres les données deviennent plus claires. / A very important tool used by applied mathematicians and engineers to model the behavior of a system are computer simulations. They have become increasingly more precise but also more complicated. So much, that they are very slow to produce an output and thus difficult to sample so that many aspects of these simulations are not very well understood. For example, in many cases they depend on parameters whose value isA metamodel is a reconstruction of the simulation. It requires much less time to produce an output that is close to what the simulation would. By using it, some aspects of the original simulation can be studied. It is built with very few samples and its purpose is to replace the simulation.This thesis is concerned with the construction of a metamodel in a particular context called multi-fidelity. In multi-fidelity the metamodel is constructed using the data from the target simulation along other samples that are related. These approximate samples can come from a degraded version of the simulation; an old version that has been studied extensively or a another simulation in which a part of the description is simplified.By learning the difference between the samples it is possible to incorporate the information of the approximate data and this may lead to an enhanced metamodel. In this manuscript two approaches that do this are studied: one based on Gaussian process modeling and another based on a coarse to fine Wavelet decomposition. The fist method shows how by estimating the relationship between two data sets it is possible to incorporate data that would be useless otherwise. In the second method an adaptive procedure to add data systematically to enhance the metamodel is proposed.The object of this work is to better our comprehension of how to incorporate approximate data to enhance a metamodel. Working with a multi-fidelity metamodel helps us to understand in detail the data that nourish it. At the end a global picture of the elements that compose it is formed: the relationship and the differences between all the data sets become clearer.
155

Tuning the RNAPII elongation rate is required for optimal pre-mRNA splicing efficiency and fidelity

Aslanzadeh, Vahid January 2017 (has links)
Splicing mainly occurs co-transcriptionally, suggesting that transcription and premRNA splicing could be synchronized. The nature of this phenomenon suggests that transcription elongation rate may influence splicing outcomes and, indeed, there is evidence for effects on alternative splicing in mammals. To elucidate potential effects of transcription rate on splicing efficiency and fidelity, splicing of nascent transcripts was investigated in fast and slow elongating RNA polymerase II (RNAPII) mutants in Saccharomyces cerevisiae. High kinetic resolution 4-thio Uracil labelling of nascent RNA reveals that fast RNAPII accumulates unspliced pre-mRNA that represents reduced co-transcriptional splicing. Conversely, low levels of unspliced pre-mRNA were detected in the slow mutant due to increased co-transcriptional splicing. The highly stable association of nascent transcripts with elongating RNAPII permits co-transcriptional splicing to be measured by analysis of transcripts that co-purify with RNAPII. Measuring co-precipitation of the spliced mRNA and excised intron that are associated with RNAPII demonstrates that splicing is mostly co-transcriptional with the slow mutant, and the fast mutant reduces co-transcriptional splicing. How elongation rate affects splicing fidelity in budding yeast and whether faster and slower transcription have the opposite effect on splicing fidelity as might be predicted by the kinetic coupling model is an open question. Using deep RNA sequencing, splicing fidelity was determined in yeast transcription elongation mutants. Results show that both fast and slow transcription reduce splicing fidelity mainly in ribosomal protein coding transcripts. Analysis reveals that splicing fidelity depends largely on intron length, secondary structure and splice site score. These analyses also provide new insights regarding the effect of altering transcription rate on selection of transcription start sites. Together, these results indicate that optimal splicing efficiency and fidelity require finely-tuned transcription speed.
156

Using the auxin-inducible degron to study the spliceosome cycle and splicing fidelity

Mendoza Ochoa, Gonzalo Ismael January 2017 (has links)
I investigated two aspects of in vivo splicing that are poorly understood: spliceosome disassembly and recycling, and proofreading. To this end, I used the auxin-inducible degron (AID) to individually deplete several splicing factors in budding yeast and then I measured the effect on co-transcriptional spliceosome assembly through chromatin immunoprecipitation. In addition, using RNA next-generation sequencing, I measured the frequency of splicing errors following depletion or mutation of the fidelity factor, Prp22. I show that formation of the pre-spliceosome (the first stage of spliceosome assembly) is rapidly inhibited by global defects in late stages of spliceosome assembly. I demonstrate that this is due to the accumulation of arrested spliceosomes that sequester the splicing machinery and, as a result, causes a recycling defect. This suggests that spliceosomes that lack essential splicing factors are not always properly disassembled and recycled in vivo, and warns about potential systematic secondary effects when perturbing single components of the spliceosome. Secondly, I describe the development of a new version of the AID system for budding yeast, called the B-estradiol AID. To the best of my knowledge, an AID system for budding yeast that is fast-acting, tightly-controlled and gratuitous, was lacking until now. Lastly, I show that absence of Prp22 protein, which was previously proposed to play a role in splicing fidelity, correlates with more mistakes in 3’ss selection of many endogenous intron-containing transcripts in vivo. This provides indirect evidence to suggest that Prp22-dependent splicing proofreading is physiologically important. The data from this analysis will be useful in ongoing studies to try to identify common features that could improve our understanding of the mechanism of Prp22’s function in splicing proofreading.
157

Simulatorbaserad träning av Eco-driving

Nyberg, Viktor January 2018 (has links)
Användandet av simulatorer i utbildningar ökar mer och mer. Simulatorer har använts inom pilotutbildningar och inom medicinsk utbildning länge och det finns mycket forskning som stödjer deras effektivitet. Nu har simulatorerna blivit mer tillgängliga i och med den tekniska utvecklingen och har börjat användas för förarutbildningar. Däremot saknas samma gedigna vetenskapliga stöd som finns för pilotutbildningar och medicinsk utbildning. Det finns visst underlag för utbildning i riskmedvetenhet men inte så många andra färdigheter. Syftet med studien var att undersöka hur effektiv en simulator är vid utbildning av förare i Eco-driving. Till studien rekryterades 20 elever från Yrkesakademin som utbildas för behörighet C, tung lastbil. Studien var av mellangruppsdesign där experimentgruppen tränade Eco-drivingfärdigheter och data över bränsleförbrukning och hastighet samlades in. Kontrollgruppen fick en teoretisk utbildning i Eco-driving i form av en inspelad video. Experimentgruppen hade en signifikant förbättring av bränsleförbrukning men inte kontrollgruppen. Detta stödjer effektiviteten av simulatorbaserad utbildning av Eco-driving. Resultaten är även uppmuntrande till träning av liknande färdigheter som bland annat är av betydelse för trafiksäkerhet. Dessutom finns det goda möjligheter att minska kostnaderna vid förarutbildningar samtidigt som eleverna lär sig bättre. / The use of of simulators in education is increasing. The aviation and medical education have a long history of implementing simulator training and education. With a strong body of scientific research that validates their use in education. As the technical development has increased, the availability of affordable simulators has increased their use in driver education. Unfortunately the research is not as strong as with the aviation or medical education. There are some support that simulator-based education can improve hazard perception but not so many other skills. Therefore I want to examine the effectiveness of a simulator in teaching Eco-driving skills to drivers. 20 students from Yrkesakademin were recruited as they were learning to drive trucks. The study is of between group design where the experimental group practiced Eco-driving skills in the simulator. Data were collected of the participants fuel consumption and speed. The control group were shown a video lecture on Eco-driving. The experimental group did significant improve while the control group did not. These results support the effectiveness of simulator-based education of Eco-driving skills. It also is encouraging for similar driving skills that can have a significant effect on traffic safety. While there is encouraging evidence for reducing the cost of driver education at the same time the students learning is enhanced.
158

Is Ecological Restoration Successful? An Assessment of a Prairie Restoration in Northern Illinois, USA

Hansen, Michael 01 January 2009 (has links)
The prairie communities that once dominated the landscape of Illinois have been reduced to a fraction of their former extent. Subsequently, considerable effort has been invested in the restoration of these lost communities, yet the comprehensive assessment of restoration success has only recently garnered interest. The objectives of this study were 1) to gauge the success of a prairie restoration project by measuring the components of ecological fidelity (structure/composition, function, and durability), and 2) to determine the factors that influenced success. Nineteen prairie plantings (ranging from two to 19 growing seasons old) at The Nature Conservancy's Nachusa Grasslands preserve were chosen for the assessment. Floristic quality was calculated to assess the composition component of ecological fidelity. Aboveground net primary productivity, soil bulk density, total soil nitrogen and total soil carbon were measured to assess the function component (soil measurements were taken at 0-5 and 5-15 cm depths). Results were compared to benchmark values taken from the literature and from samples of remnant prairies. Durability was determined by comparing measurements across a restoration chronosequence. To further evaluate the prairie plantings and restoration success, non-metric multidimensional scaling ordination was used to compare plantings based on their vegetation composition and soil characteristics (prairie remnants were also included in the comparison based on soil characteristics). Values of Mean C and FQI indicated successful levels among younger plantings, but durability was less successful according to the chronosequence. Seed-mix quality had the greatest influence (positive) on composition success. Aboveground net primary productivity levels were successful and durable overall, however, younger plantings exhibited successful levels of production more consistently than older plantings. Aboveground net primary productivity was most influenced (negatively) by the abundance of the exotic C3 grass genera Poa and Bromus. Functional success based on soil characteristics was limited. Soil bulk density, total nitrogen, and total carbon levels all differed among plantings and remnants at both depths, and evidence of levels recovering toward levels of remnants was not detected. The results of this study indicated that some components of ecological fidelity have been successfully restored, while others have not, and using a high-quality seed mix that resembles the species pool of remnant prairie and limiting the abundance of the dominant native C4 and exotic C3 grasses can improve the restoration of plant composition and ecological function in Illinois prairie plantings. The mixed results underscore the importance of examining more than one component of ecological fidelity when measuring success. Long-term monitoring is also recommended for evaluating restoration durability, especially for detecting changes among soil properties over time.
159

Informative Prior Distributions in Multilevel/Hierarchical Linear Growth Models: Demonstrating the Use of Bayesian Updating for Fixed Effects

Schaper, Andrew 29 September 2014 (has links)
This study demonstrates a fully Bayesian approach to multilevel/hierarchical linear growth modeling using freely available software. Further, the study incorporates informative prior distributions for fixed effect estimates using an objective approach. The objective approach uses previous sample results to form prior distributions included in subsequent samples analyses, a process referred to as Bayesian updating. Further, a method for model checking is outlined based on fit indices including information criteria (i.e., Akaike information criterion, Bayesian information criterion, and deviance information criterion) and approximate Bayes factor calculations. For this demonstration, five distinct samples of schools in the process of implementing School-Wide Positive Behavior Interventions and Supports (SWPBIS) collected from 2008 to 2013 were used with the unit of analysis being the school. First, the within-year SWPBIS fidelity growth was modeled as a function of time measured in months from initial measurement occasion. Uninformative priors were used to estimate growth parameters for the 2008-09 sample, and both uninformative and informative priors based on previous years' samples were used to model data from the 2009-10, 2010-11, 2011-12, 2012-13 samples. Bayesian estimates were also compared to maximum likelihood (ML) estimates, and reliability information is provided. Second, an additional three examples demonstrated how to include predictors into the growth model with demonstrations for: (a) the inclusion of one school-level predictor (years implementing) of SWPBIS fidelity growth, (b) several school-level predictors (relative socio-economic status, size, and geographic location), and (c) school and district predictors (sustainability factors hypothesized to be related to implementation processes) in a three-level growth model. Interestingly, Bayesian models estimated with informative prior distributions in all cases resulted in more optimal fit indices than models estimated with uninformative prior distributions.
160

Effects of Self-delivered Performance Feedback and Impact Assessment via the Individual Student Information System (ISIS-SWIS) on Behavior Support Plan Treatment Fidelity and Student Outcomes

Pinkelman, Sarah 17 October 2014 (has links)
The success of behavioral interventions depends not just on the quality of procedures employed but on the extent to which procedures are implemented. This study used a multiple-baseline across participants single-case design to assess the impact of an online data management application (the Individual Student Information System; ISIS- SWIS) on the fidelity and impact of individual student behavior support plans in typical school contexts. Three students with patterns of problem behavior and their supporting adults participated in the study. The research question examined if a functional relation exists between use of (a) performance self-assessment and (b) student impact assessment via ISIS-SWIS on the fidelity of behavior support plan implementation by adults and improvement in academic engagement and problem behavior by students. Results indicate the efficacy of ISIS-SWIS in improving treatment fidelity, decreasing student problem behavior, and increasing student academic engagement. Potential contributions of the study are discussed in terms of establishing efficient data systems for schools to use in monitoring staff and student behavior and using these data in a meaningful way that results in improved student outcomes and sustained behavior change.

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