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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.
211

Survey of Bicycle Trail-Users in New Orleans: Characteristics, Attitudes and Implications for Planning

Judge, Coleen 17 December 2010 (has links)
This thesis focuses on bicyclists using the Jefferson Davis multi-use, off-street trail in the City of New Orleans. Understanding user characteristics and perceptions of bicyclists will help inform planning, policy, and design related to bicycle infrastructure. This thesis uses a review of the relevant literature, intercept surveys of bicyclists, and automatic bicycle counts to understand how user characteristics can influence successful bicycle design, policies, and planning. The user characteristics of the bicyclists on the Jefferson Davis Trail provide us with information on who is using the trail, how often, why, and what users would like to see improved. Planners need to understand the motivations of the current and potential trail users. Making bicycling a safe mode of travel in an urban area involves influencing citizens at both the socialecological level and the travel-behavioral level, providing the culture around bicycling and the facilities available to do so.
212

Here Goes Nothing: Creating The Role Of Timothy Allgood In "Noises Off."

Bupp, Justin G 18 December 2015 (has links)
Noises Off is the epitome of farce. Doors everywhere, mistaken identities, and unrequited love. The characters push themselves to the limit, both mentally and physically. They stop at nothing to put on their production and their stage manager, Timothy Allgood, becomes the babysitter of the group, which at times becomes comparable to herding cats. This document describes the journey made from casting to final bows. It contains biographical research on the playwright, Michael Frayn, as well as a historical look at the genre of farce, techniques pioneered by Sanford Meisner and Konstantin Stanislavski, along with materials, including a scored script, character analysis, personal evaluation, and rehearsal reflections.
213

Off-ice tester för att utvärdera snabbhet on-ice : En korrelationsstudie av olika upprepade sprinttester

Alfredsson, Tim, Selin, Anders January 2017 (has links)
Syfte Syftet med studien är att undersöka korrelationen mellan cykeltestet "repeated 5 second cycling sprint test" (R5sCST) samt off-ice testet 36 meter upprepade sprinter (OfI) mot on-ice testet 33 meter upprepade sprinter (OnI). Samtidigt vill vi se om R5sCST kan utvärdera skridskosnabbhet samt undersöka om OfI kan användas som en alternativ testmetod med samma syfte. De frågeställningar vi besvarar är, – Finns det en korrelation mellan R5sCST och OnI? - Finns det en korrelation mellan OfI och OnI? – Är R5sCST och OfI relevanta testmetoder för att utvärdera förmågan till upprepade sprinter on-ice? - Finns det andra testvärden som kan förutse snabbhet on-ice? Metod 3 tester har genomförts, ett cykeltest (R5sCST), ett on-ice test (OnI) och ett off-ice test (OfI). Testerna genomfördes på Bosön och i Björkängshallen vid två olika tillfällen, det var 2 dagar mellan testtillfällena. Testtillfälle 1 genomfördes R5sCST och OfI på Bosön, testtillfälle 2 genomfördes OnI i Björkängshallen. 18 stycken ishockeyspelare på junior elitnivå testades. Försökspersonerna (FP) var mellan 16 och 18 år gamla och har en idrottslig bakgrund inom ishockey som motsvarar 11-13 år. Resultat Studien visar att såväl medelvärdena samt de högst uppmätta effekt värdena hos varje FP från R5sCST testet korrelerar med medel- och högsta värden på OnI. Studien visar även en starkare korrelation mellan OfI och OnI. Slutsats Efter genomförd studie kan det konstateras att R5sCST, trots att det inte efterliknar ishockeyns krav fullt ut i arbetstid/vilotid, är ett reliabelt test för att utvärdera snabbhet on-ice. Det framkommer även i studien att OfI har större korrelationer till OnI än vad R5sCST har, vilket innebär att även OfI är ett högst reliabelt test för att utvärdera snabbhet on-ice. Förutom större korrelationer så är även OfI mer lämpat för lag och föreningar att använda sig av då det är enklare att utföra och mindre kostsamt än R5sCST. / <p>Ämneslärarprogrammet, Specialidrott</p>
214

Vätgas som energilagringsmedium för energi från förnyelsebara energikällor

Östergren, Linus January 2019 (has links)
En omställning till ett mer hållbart samhälle pågår både nationellt och internationellt. Arbete läggs på att öka andelen förnyelsebara energikällor där solceller är en populär produkt. När effekttopparna och de förnyelsebara energikällorna ökar i det svenska stamnätet så skapas ett behov av att lagra stora mängder energi. Att lagra den mängden energi i batterier skulle bli kostsamt. Resultatet från utredningen tyder på att vätgas är ett lämpligt alternativ då omvandlingsprocesserna genererar både elektrisk och termisk energi. Komponenterna som används är ursprungligen från industrin vilket gör dom överdimensionerade för vanliga hushåll. Optimalt används vätgassystem i flerfarmilsbostäder där både den termiska energin och elektriska energin kan nyttjas.
215

Comportamento de íons fora de centro em halogenetos alcalinos / Behaviour of off-center ions in alkali halides

Li, Maximo Siu 24 November 1978 (has links)
Apresentamos resultados experimentais sobre o comportamento fora de centro do íon de Cu+ em cristais de RbCl, RbBr, RbI, NaI e em cristais mistos de KI +%KCl e KCl +%KI; como também do íon de Ag+ em RbI. Usamos técnicas de absorção ótica no ultra travioleta, corrente termoestimulada (ITC) e dicroísmo induzido por pressão uniaxial. Com estas técnicas, determinamos o comportamento da força do oscilador em dependência com a temperatura, energia de ativação, tempo de relaxação em dependência com a temperatura, momento dos dipolos elétricos, a mudança de configuração do íon de Cu + na reorientação num sistema de multipoço trigonal . puro para um multipoço ortorrómbico no crital misto de KI+1%KCl. Detetamos pela primeira vez a relaxação por ativação térmica de bandas de ITC a temperatura relativamente baixa, como é o caso do íon de Ag+ em RbI que acontece em 24&ordm;K. Ainda, apresentamos alguns resultados sobre o comportamentp do íon de Li + que fica fora de centro no KC1, em cristais de KCl contendo centros U de H- e de D-, usando absorção ótica no infravermelho médio. / Experimental results are given on the off-center behavior of Cu+ ion in RbCl, RbBr, Hbl, NaI and in mixed crystals of KI+%KCl and KCl+%KI, as also on Ag+ in RbI. We use UV optical absorption, ionic thermal current (ITC) and uniaxial stress induced dichroism techniques. It is studied the temperature dependence of the oscillator strength, the relaxation time and the electric dipo1e moment are determined in the above crystals. We observe and discuss the change on the equi1ibrium configuration trigonal of the Cu+ ion in KI to the ortorrhombic in Kl+%KCl mixed crystal. For the first time we detect with the ITC measurements a thermal activated process at low temperature (24&ordm;K), this behaviour occurs in RbI:Ag+. Using mid-infrared absorption measurements, we give several results and discussions on the U centers (either H- or D-) perturbed by Li+ ion in KCl crystals.
216

Reator anaeróbio alimentado com vinhaça de cana-de-açúcar: avaliação dos efeitos causados pela interrupção na alimentação e estratégias para mitigação / Anaerobic reactor fed with sugarcane vinasse: evaluation of the effects caused by interruption in feeding and strategies for mitigation

Barbosa, Moara Yuri Utino 04 August 2017 (has links)
O tratamento biológico anaeróbio aparece como uma opção importante para remover a carga orgânica poluidora da vinhaça, e vem despertando interesse entre pesquisadores do mundo todo devido aos sucessos já alcançados, principalmente em trabalhos científicos. O interesse científico aponta para o aprimoramento do processo de degradação desse efluente em taxas elevadas, além de promover a produção de biogás, com potencial para produção de energia. A tecnologia de tratamento anaeróbio mais utilizada para o tratamento da vinhaça é o reator UASB, apresentando resultados satisfatórios inclusive em unidades em escala plena. A interrupção do funcionamento do reator em períodos de entressafra é, indubitavelmente, um problema a ser enfrentado na operação do reator UASB, cujo período de partida é lento. A repartida do sistema é agravada nos reatores de alta taxa, requerendo estratégias adequadas para reduzir o período necessário permitindo mitigar prontamente os efeitos do aporte de vinhaça ao ambiente e recuperar energia a partir dessa matriz. Diante disso, um reator anaeróbio de fluxo ascendente com manta de lodo (UASB) em escala piloto foi utilizado para o estudo da repartida do sistema e do tratamento da vinhaça e do melaço, sendo o último utilizado como fonte de carbono no período relativo à entressafra. O reator UASB foi operado durante 335 dias. Na Fase I utilizou-se a vinhaça como afluente, na Fase II o melaço de cana-de-açúcar e na Fase III novamente a vinhaça. Após período de interrupção de 30 dias, o período de repartida do sistema em estudo foi de 69 dias. Logo no início da repartida do reator, a eficiência de remoção de DQO foi superior a 80%, alcançando eficiência de 89,95 % em apenas oito dias de operação. O reator UASB apresentou valor médio de eficiência de remoção de DQO para as Fases I (vinhaça), II (melaço) e III (vinhaça) de 84 ± 3,35%; 82 ± 5,12% e 80 ± 9,22%, para cargas aplicadas de 5 a 34 kgDQO.m-3.d-1, 33 kgDQO.m-3.d-1 e 5 a 19 kgDQO.m-3.d-1, respectivamente. Em relação à produção de metano, de todo o período operacional, a Fase I referente à repartida do reator utilizando vinhaça como substrato após um mês sem alimentação foi a que apresentou a maior produção média no período, 7,93 LCH4. (L.d) -1, devido aos maiores valores de carga orgânica volumétrica (COV) aplicadas (5 a 34 kgDQO.m-3.d-1). A Fase II referente ao período de entressafra utilizando o melaço, foi de 7,28 LCH4. (L.d) -1 devido ao acúmulo de ácidos voláteis totais. A Fase III com retorno da safra utilizando a vinhaça, foi de 1,23 LCH4. (L.d) -1 devido aos menores valores de carga aplicada ao reator (5 a 8,5 kgDQO.m-3.d-1). As análises microbiológicas mostraram elevada diversidade microbiana e permitiu observar que com a utilização do melaço ocorreu alteração da população de microrganismos presente no reator, que apresentaram longo período de adaptação quando submetidos novamente à vinhaça, na última fase de operação. De forma geral, os resultados apontam que a tecnologia UASB é adequada no tratamento de vinhaça e melaço de alta carga orgânica e na geração de biogás. A substituição por melaço permitiu obter produção de biogás semelhante ao uso da vinhaça, entretanto dificultou a repartida, quando substituído pela vinhaça novamente (Fase III). / Biological anaerobic treatment systems are a promising approach for the removal of organic loading content of vinasse. Previous studies have demonstrated the optimization of the vinasse degradation process at high rates, promoting the biogas production with potential for energy use. Upflow anaerobic with sludge blanket (UASB) is the most applied anaerobic technology for the treatment of vinasse. Such reactor configuration presents satisfactory results even in full-scale units. The interruption of reactor operation during the off-season is undoubtedly an operational problem to be faced, whose restarting period is slow. The system restarting is intensified in high-rate reactors, requiring adequate strategies to reduce the time needed to mitigate the environmental effects of vinasse supply and to recover energy from that matrix. Therefore, a pilot-scale UASB was used to investigate the system restart and the treatment of vinasse and molasses. Sugarcane molasses was used as the carbon source during the off-season period. The system was operated during 335 days. The operational procedure consisted of three phases, in which different streams were used as carbon source: vinasse (Phases I), sugarcane molasses (Phases II) and vinasse (Phases III). After an interruption period of 30 days, the restarting period was 69 days. At the beginning of the restarting period, the average COD removal efficiency was higher than 80%, reaching COD removal efficiencies of 89.95% in only eight days of operation. The average COD removal efficiencies for Phases I (vinasse), II (molasses) and III (vinasse) were 84 ± 3.35%; 82 ± 5,12% and 80 ± 9,22%, respectively. Those removal efficiencies were achieved with organic loading rate 5 to 34 kgCOD.m-3.d-1 , 33 kgCOD.m-3.d-1 and 5 to 19 kgCOD.m-3.d-1, respectively. Regarding methane (CH4) production, Phase I (vinasse as substrate after one month without feeding) presented the highest average CH4 production (7.93 LCH4. (L.d) -1), due to the higher values of OLR (5 to 34 kgCOD.m-3.d-1). The CH4 production during Phase II (off-season using molasses as substrate) was 7.28 LCH4. (L.d) -1, due to the accumulation of volatile fatty acids (VFA). In Phase III, in which vinasse was applied again as substrate the CH4 production was 1.23 LCH4.(L.d)-1, due to the lower values of organic loading rate to the reactor (5 to 8.5 kgCOD.m-3.d-1). Microbiological analyses showed high microbial diversity in biomass developed at UASB reactor. Moreover, it was possible to observe that with molasses used as carbon source probably promotes changes in the microorganisms population, After period with molasses feeding, such microbiota presented a long adaptation period when resubmitted to vinasse, as the main carbon source in the feeding. In general, the results indicate that the UASB configuration was adequate for the vinasse and molasses treatment at high organic loading rate, resulting in high biogas production. In which the feeding with sugarcane molasses resulted in a biogas production similar to that obtained by vinasse feeding, but it made it difficult to divide when replaced by vinasse (Phase III).
217

Podnikatelské klima v zemích procházejících transformací na příkladu České republiky / Entrepreneurial climate in countries in transition - the example of the Czech Republic

Jakl, Martina January 2007 (has links)
Doktorská práce se zaměřuje na podnikatelské klima v zemích procházejících transformací s konkrétním zaměřením na Českou republiku a její srovnání vůči Švýcarsku. Metodou grounded theory porovnává možnosti zakládání nových akademických spin-off v obou zemích a hodnotí klíčové faktory v dané oblasti. Práce se opírá o rozsáhlý soubor literatury stejně jako o vlastní výzkum.
218

Podnikatelské klima v zemích procházejících transformací na příkladu České republiky / Entrepreneurial climate in countries in transition - the example of the Czech Republic

Jakl, Martina L. January 2007 (has links)
Doktorská práce se zaměřuje na podnikatelské klima v zemích procházejících transformací s konkrétním zaměřením na Českou republiku a její srovnání vůči Švýcarsku. Metodou grounded theory porovnává možnosti zakládání nových akademických spin-off v obou zemích a hodnotí klíčové faktory v dané oblasti. Práce se opírá o rozsáhlý soubor literatury stejně jako o vlastní výzkum.
219

High-Efficiency Doherty-Based Power Amplifiers Using GaN Technology For Wireless Infrastructure Applications

January 2018 (has links)
abstract: The continuing advancement of modulation standards with newer generations of cellular technology, promises ever increasing data rate and bandwidth efficiency. However, these modulation schemes present high peak to average power ratio (PAPR) even after applying crest factor reduction. Being the most power-hungry component in the radio frequency (RF) transmitter, power amplifiers (PA) for infrastructure applications, need to operate efficiently at the presence of these high PAPR signals while maintaining reasonable linearity performance which could be improved by moderate digital pre-distortion (DPD) techniques. This strict requirement of operating efficiently at average power level while being capable of delivering the peak power, made the load modulated PAs such as Doherty PA, Outphasing PA, various Envelope Tracking PAs, Polar transmitters and most recently the load modulated balanced PA, the prime candidates for such application. However, due to its simpler architecture and ability to deliver RF power efficiently with good linearity performance has made Doherty PA (DPA) the most popular solution and has been deployed almost exclusively for wireless infrastructure application all over the world. Although DPAs has been very successful at amplifying the high PAPR signals, most recent advancements in cellular technology has opted for higher PAPR based signals at wider bandwidth. This lead to increased research and development work to innovate advanced Doherty architectures which are more efficient at back-off (BO) power levels compared to traditional DPAs. In this dissertation, three such advanced Doherty architectures and/or techniques are proposed to achieve high efficiency at further BO power level compared to traditional architecture using symmetrical devices for carrier and peaking PAs. Gallium Nitride (GaN) based high-electron-mobility (HEMT) technology has been used to design and fabricate the DPAs to validate the proposed advanced techniques for higher efficiency with good linearity performance at BO power levels. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2018
220

TRADE-OFF BALANCING FOR STABLE AND SUSTAINABLE OPERATING ROOM SCHEDULING

Abedini, Amin 01 January 2019 (has links)
The implementation of the mandatory alternative payment model (APM) guarantees savings for Medicare regardless of participant hospitals ability for reducing spending that shifts the cost minimization burden from insurers onto the hospital administrators. Surgical interventions account for more than 30% and 40% of hospitals total cost and total revenue, respectively, with a cost structure consisting of nearly 56% direct cost, thus, large cost reduction is possible through efficient operation management. However, optimizing operating rooms (ORs) schedules is extraordinarily challenging due to the complexities involved in the process. We present new algorithms and managerial guidelines to address the problem of OR planning and scheduling with disturbances in demand and case times, and inconsistencies among the performance measures. We also present an extension of these algorithms that addresses production scheduling for sustainability. We demonstrate the effectiveness and efficiency of these algorithms via simulation and statistical analyses.

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