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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.
131

Heterogeneity and Collective Action: Case Studies from the United States and India

Mudliar, Pranietha, Mudliar 28 December 2016 (has links)
No description available.
132

Trycksatt luftspalt i simhallstak : Ett sätt att förhindra fuktkonvektion

Johansson, Malin, Selenius, Daniel January 2021 (has links)
Simhallar har en hög fuktbelastning från insidan som är krävande för ytterväggar och tak. Utöverdet varma och fuktiga klimatet har simhallar ofta en hög takhöjd, som i kombination med denhöga lufttemperaturen skapar ett termiskt tryck mot simhallens innertak. Via konvektion riskerarvarm och fuktig luft att strömma ut genom otätheter i takkonstruktionen till kallare delar i taketmed kondensbildning som följd.Konvektion genom taket kan hindras genom att trycksätta ett utrymme innanför simhallens takmed ett högre tryck än det högsta termiska trycket i simhallen. Syftet är att undersöka ur ettfukttekniskt perspektiv hur det trycksatta utrymmet ska utföras för att vara fuktsäkert.Rapporten omfattar en redogörelse för hur klimatet i simhallar har förändrats genom åren ochvilka skademekanismer som påverkar takkonstruktionen. Teoretiska fuktberäkningar görs iprogrammet Wufi 5 på en takkonstruktion i limträ som både utförs med och utan ett trycksattutrymme innanför taket i simhallen.Resultaten visar på att en takkonstruktion med ett trycksatt utrymme är en fukttekniskt säkrarelösning. Det totala vatteninnehållet i konstruktionen minskar över tid, vilket tyder på attbyggfukt torkas ut och att fukt från simhallen inte läcker ut i det trycksatta utrymmet. / Buildings with indoor swimming pools are exposed to high humidity from the inside which isstressful on the exterior walls and the roof. In addition to the warm and humid climate insidepublic baths they also often have a high ceiling height, that in combination with the high airtemperature creates a thermal pressure against the ceiling. By way of convection the warm andhumid air will escape through the ceiling construction if it is not airtight and the humid air willcondense when it reaches the colder layers.To prevent convection to occur, a pressurized space with a higher pressure than what the ceilingis exposed to in the swimming pool area can be placed above the ceiling of the public bath. Thepurpose of this study is to examine how the pressurized space can be executed to be moistureproof.This study includes a report of how the climate in indoor swimming pools have changed throughthe years, and how damage due to moisture affects the roof construction. Theoreticalcalculations are implemented on a roof construction made of glued laminated timber, calculatedboth with and without the pressurized space.The results point to that a roof construction with a pressurized space above the ceiling of theswimming pool area is a more moisture-proof solution. The total content of water in theconstruction reduces over time, which means that the construction gets dryer and no moist fromthe swimming pool area makes its way into the pressurized space.
133

A Multiscale Study of the Role of Environmental Variability on the Diversity and Abundance of Rock Pool Communities / The Role of Environmental Variability on Diversity

Reid, Lesley 09 1900 (has links)
One of the main goals of ecological research is to understand the factors that determine how communities are structured over both space and time. However, our understanding of any system is largely a function of the scale at which we make our observations. Thus, the mechanisms that determine patterns in community structure are likely to change depending on the scale of observation. This thesis explores how environmental variability affects community structure and species performance, and how the resulting patterns change as a function of scale. Specifically, I asses the role of variability in temperature, oxygen, pH, and chloride, on species richness, abundance, diversity, and species performance, at three observational scales: micro-spatial, local-temporal, and landscape-temporal scales, in 49 natural erosional rock pool microcosms, located on the northern. coast of Jamaica. I found that while environmental variability was not a primary determinant of species richness or abundance, it did play a role in determining species compositions in the pools. I also show that community patterns are strongly affected by the scale of observation. Recognizing scale-dependent changes in community patterns is a prerequisite for predicting the consequences of changes in ecological systems induced by variability in abiotic factors. / Thesis / Master of Science (MS)
134

Numerical simulation of the hydraulic performances and flow pattern of swallow-tailed flip bucket

Zhang, L., Zhang, J., Guo, Yakun, Peng, Y. 20 April 2020 (has links)
Yes / In this study, the evolution process of the swallow-tailed flip bucket water nappe entering into the plunge pool is simulated by using the standard 𝑘-𝜀 turbulence model and the volume of fluid method. The effects of the upstream opening width ratio and downstream bucket angle on the flow pattern, the unit discharge distribution and the impact pressure distribution are studied. Based on the numerical results, the inner and outer jet trajectories are proposed by using the data. Results show that the longitudinal stretching length decreases with the increase of the upstream opening width ratio, and increases with the increase of the downstream bucket angle. The water nappe enters the plunge pool in a long strip shape. Thus, the unit discharge distribution of water nappe entry is consistent with the pressure distribution at the plunge pool bottom. The upstream opening width ratio and downstream bucket angle should be chosen as their intermediate values in order to have a uniform discharge distribution and to reduce the pressure peak at the plunge pool floor, which is effectively to avoid instability and destruction of plunge pool floor. / National Science Fund for Distinguished Young Scholars (No. 51625901) and National Nature Science Foundation of China (No: 51579165).
135

A Methodology for Characterization and Performance Analysis of Connection-Based Network Access Technologies

Novak, David C. 26 April 2001 (has links)
Network administration has become more difficult as the number of Internet users has grown and customer usage patterns have changed over time. Rapidly increasing subscriber bases, data intensive applications (such as streaming audio and video), heavy Web browsing, and large file downloads require significant resources and may tax existing network bandwidth. Reliability and quality of service are becoming serious issues for service providers across the country. Due to the dynamic nature of the information technology (IT) sector in general, it is difficult to predict future network usage patterns or what types of applications may be available, and how these applications may be used over time. This research presents a methodology to facilitate capacity planning and to improve the evaluation of network performance for connection-based networks using the Virginia Tech modem pool as a test bed. The abstract research question is can innovative business strategies be employed in lieu of, or in addition to, traditional management practices such as adding capacity in order to improve the performance of a dialup network? Examples of such strategies or business rules may include limiting the duration of an online session or limiting the number of times a given customer can dial into the pool in a specified time period. A complete network traffic characterization is conducted based on service time and interarrival time variables. A longitudinal analysis is performed to examine how traffic patterns have changed over time. Finally, a simulation model is utilized to examine how imposing different business rules during peak-periods of operation can reduce the blocking probability and improve the overall level-of-service. The potential contribution of this research appears to be significant based on the lack of existing literature. / Ph. D.
136

Sanitary Aspects of the Swimming Pool of North Texas State Teachers College, Denton, Texas

Self, Louise 08 1900 (has links)
This investigation was conducted in order to show that insanitary conditions may exist in the swimming pool at North Texas State Teachers College provided the proper precautions are not taken; and, in contrast that this pool can be sanitary and entirely safe when operated and used according to the necessary sanitary specifications.
137

Desenvolvimento de estratégia de genotipagem para discriminação de alelos antitéticos do sistema de grupo sanguíneo Diego utilizando pool de DNA / Development of genotyping strategy for discrimination of antithetical alleles of the Diego blood group system using DNA pool

Carvalho, Thiago Vianna de 07 May 2018 (has links)
Nesta dissertação, foi proposto o desenvolvimento de uma metodologia molecular por PCR em tempo real (qPCR) utilizando pool de DNA para a detecção de alelos que codificam antígenos importantes do sistema de grupo sanguíneo Diego. Esta ferramenta molecular será útil uma vez que são escassos os reagentes sorológicos para detecção desses antígenos e, quando existem, não permitem uma investigação em larga escala devido à pouca confiabilidade e alto custo. O sistema Diego (DI) possui 22 antígenos, sendo o antígeno Diª mais importante na prática transfusional. Eles são carreados pela proteína da Banda 3 que é proteína mais abundante na s hemácias, com 106 cópias. O antígeno possui uma maior prevalência, em indígenas americanos e asiáticos (6%-52%), já que é considerado um marcador antropológico de ancestrais mongóis; no entanto, a incidência desse antígeno tem aumentado dentre outras populações, como em caucasianos e afrodescendentes, e detectado em doadores de sangue, o que pode resultar em aloimunização de pacientes e dificultando o seu manejo terapêutico. Em contrapartida, a frequência do antígeno Dib em todas as populações é extremamente alta (>99,99%) e encontrar o raro fenótipo Di (a+b-) é ainda mais laborioso do que a busca pelo antígeno Diª. Sabe-se ainda muito pouco sobre a frequência dos antígenos Wrª e Wrb nas diferentes populações, mas estimase que a prevalência seja de 0,01% e >99,99% respectivamente. Foram utilizadas 410 amostras de doadores de sangue e 230 amostras de pacientes para genotipagem em qPCR utilizando pool de DNA para detecção dos alelos DI*01, DI*02, DI*02.03 e DI*02.04. A amplificação individualizada foi realizada quando a reação com pool demonstrou a amplificação de um dos alelos de interesse, DI*01 ou DI*02.03. Procedeu-se também com a clonagem dos alelos após à amplificação com as amostras controle, porém, ocorreu somente a clonagem dos alelos DI*02 e DI*02.03. Os fragmentos clonados apresentaram amplificação excelente e serão utilizados como controle positivo em testes moleculares futuros. Não foi possível a clonagem do DI*01 pelo problema da zigozidade da amostra controle. Houve 100% de concordância entre o resultado da genotipagem e as informações de fenotipagem das amostras controle. O alelo DI*01 ocorreu em 0,6% dos doadores de sangue e 1,7% em afrodescendentes, que corresponde a uma frequência genotípica DI*01/DI*02 de 1,2% e 1,3% respectivamente. Procedeu-se com as análises estatísticas comparativas entre o resultado desta pesquisa e de outras na população brasileira sobre os diferentes genótipos para entender se havia uma diferença estatística considerável. Ainda que a frequência para o genótipo DI*01/DI*02 seja mais baixa em doadores e mais alta em afrodescendentes do que o publicado em outros trabalhos brasileiros, a análise dos dados demonstrou que não havia diferença estatística com a maioria deles. A incidência aumentada do alelo DI*01 na população afrodescendente demonstra o aspecto da miscigenação. Conclui-se que a metodologia proposta funciona e tem aplicabilidade imediata em doadores de sangue e na busca de fenótipos raros. A incidência do alelo para Diª em doadores de sangue está abaixo do que um estudo anterior detectou em Ribeirão Preto (COZAC, 2004), que pode ser explicado pelas diferenças no censo populacional entre os estudos e pela coleta de amostra de universitários (62%). Não foram encontrados os genótipos DI*01/DI*01, DI*02.03/DI*02.03 e DI*02.03/DI*02.04 nas populações estudadas. / This work proposed the development of a molecular methodology by Real Time-PCR (qPCR) using DNA pool for the detection of alleles that encode important antigens of the Diego blood group system. This molecular tool will be useful since the serological reagents for the detection of these antigens are scarce and, when they exist, do not allow a large scale investigation due to the low reliability and high cost. The Diego (DI) system has 22 antigens, the Diª antigen is the most important in transfusion practice. They are carried by the Band 3 protein which is the most abundant protein on the erythroid surface, about 106 copies. The antigen has a higher prevalence in american indians and asians (6%-52%), since it is considered an anthropological marker of Mongolian ancestors; however, the incidence of this antigen has increased among other populations, such as in caucasians and afrodescendants, and detected in blood donors, which may result in alloimmunization of patients and make difficult their therapeutic management. In contrast, the frequency of Dib antigen in all populations is extremely high (>99.99%) and finding the rare phenotype Di (a+b-) is even more laborious than the search for Diª antigen. The frequency of Wrª and Wrb antigens in different populations is not well-known, but it is estimated that the prevalence is 0.01% and >99.99% respectively. 410 blood donor samples and 230 patient samples were used for genotyping in qPCR using DNA pool to detect the alleles DI*01, DI*01, DI*02.03 and DI*02.04. The single amplification was performed when the pool reaction demonstrated the amplification of one of the alleles of interest, DI*01 or DI*02.03. The alleles were also cloned after the control samples amplification. Only the cloning of the DI*02 and DI*02.03 alleles occurred, they presented excellent amplification and will be used as positive controls in future molecular tests, it was not possible to clone DI*01 by the control sample zygosity though. There was 100% agreement between the genotyping results and the phenotype information of the control samples. The DI*01 allele occurred in 0,6% of the blood donors and 1,7% in afrodescendants, which corresponds to a genotypic frequency DI*01/DI*02 of 1,2% and 1,3% in respectively. The comparative statistical analyzes between this research results and others in the Brazilian population on the different genotypes was performed to understand if there was a considerable statistical difference. Although the frequency of the genotype DI*01/DI*02 is lower in donors and higher in afrodescendants than that published in other Brazilian studies, data analysis showed that there was no statistical difference with most of them. The increased incidence of the DI*01 allele in the afrodescendant population demonstrates the aspect of miscegenation. It is concluded in this work that the proposed methodology works and has immediate applicability in the screening of blood donors and search for rare phenotypes. The incidence of the allele encoding Di ª antigen in blood donors is below than previously detected in Ribeirão Preto (COZAC, 2004), which can be explained by the differences in the population census between the studies and by the sample collection of university students (62%). The genotypes DI*01/DI*01, DI*02.03/DI*02.03 and DI*02.03/DI*02.04 were not found in the populations studied.
138

Kvartalo/objekto aprūpinimo šilumine energija variantų analizė / Analysis of Variants of Heat Supply for a District/Object

Pladas, Karolis 11 June 2014 (has links)
Magistro baigiamajame darbe aptariamas Lietuvos ir Europos Sąjungos šalių energetikos sektorius. Apžvelgiamos direktyvos, strategijos, plėtros planai bei teisės aktai skirti energetikos plėtojimui šalyje. Tiriamuoju objektu pasirenkama Trakų Vokės katilinė, kuri aprūpina šiluma kvartalą degindama gamtines dujas vandens šildymo katiluose. Šiame darbe yra nagrinėjamos penkios alternatyvos: kogeneratorius ir dujiniai katilai, kogeneratorius su akumuliacine talpa ir dujiniais katilais, kogeneratorius su akumuliacine talpa ir biokuro katilais, kogeneratorius su akumuliacine talpa ir šilumos siurbliu, medienos dujofikavimo reaktorius su kogeneratoriumi ir vandens šildymo katilais. Alternatyvos yra nagrinėjamos dviem skirtingais scenarijais, kai kogeneratoriaus pagaminta elektra parduodama pagal VIAP tarifus ir pagal „Nord pool spot“ Lietuva biržos kainas. Tiriamasis darbas atliekamas naudojantis „energyPRO“ modeliavimo programa. Atlikus modeliavimą, sistemų veikimas įvertinamas pirminės energijos suvartojimu, ekologiniu ir ekonominiu požiūriais. Atliekama jautrumo analizė keičiant ekonominius rodiklius bei vertinant šilumos gamybą be kogeneracijos. Pagal gautus rezultatus suformuluojamos išvados. Darbą sudaro 10 skyrių. Apimtis – 79 psl. teksto be priedų, 47 iliustracijų, 10 lentelių, 74 bibliografiniai šaltiniai. / In this master thesis, Lithuanian and European Union’s countries energy sector was discussed. An overview was made on EU directives, Lithuanian strategies, development plans and legalizations. Investigation object was Trakų Vokė boiler house with its district heating system. In the boiler house heat produced by combusting natural gas. During the research five alternatives were analysed: cogeneration and heat only boilers, cogeneration with thermal storage and heat only boilers, cogeneration with thermal storage and biomass heat only boilers, cogeneration with thermal storage and high temperature heat pump, biomass gasification reactor with cogeneration and heat only boilers. Alternatives are analysed based on two scenarios, first on when cogeneration is working by fixed electricity tariffs and second when cogeneration is working by liberalized electricity market conditions. Thesis carried out using “energyPRO” modelling software. All modelled systems are assessed by techno-economic and ecological approach. A sensitivity analysis was made by changing economical values and assessing systems without cogeneration. Based on the results conclusion was formed. Thesis includes 10 chapters. Size of work – 79 pages excluding appendixes, 47 pictures, 10 tables, 74 reference sources.
139

An intertidal survey of Cape d'Aguilar, Hong Kong with special reference to the ecology of high-zoned rock pools /

Cheung, Pui-shan, Catherine. January 1991 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1991.
140

Desenvolvimento de estratégia de genotipagem para discriminação de alelos antitéticos do sistema de grupo sanguíneo Diego utilizando pool de DNA / Development of genotyping strategy for discrimination of antithetical alleles of the Diego blood group system using DNA pool

Thiago Vianna de Carvalho 07 May 2018 (has links)
Nesta dissertação, foi proposto o desenvolvimento de uma metodologia molecular por PCR em tempo real (qPCR) utilizando pool de DNA para a detecção de alelos que codificam antígenos importantes do sistema de grupo sanguíneo Diego. Esta ferramenta molecular será útil uma vez que são escassos os reagentes sorológicos para detecção desses antígenos e, quando existem, não permitem uma investigação em larga escala devido à pouca confiabilidade e alto custo. O sistema Diego (DI) possui 22 antígenos, sendo o antígeno Diª mais importante na prática transfusional. Eles são carreados pela proteína da Banda 3 que é proteína mais abundante na s hemácias, com 106 cópias. O antígeno possui uma maior prevalência, em indígenas americanos e asiáticos (6%-52%), já que é considerado um marcador antropológico de ancestrais mongóis; no entanto, a incidência desse antígeno tem aumentado dentre outras populações, como em caucasianos e afrodescendentes, e detectado em doadores de sangue, o que pode resultar em aloimunização de pacientes e dificultando o seu manejo terapêutico. Em contrapartida, a frequência do antígeno Dib em todas as populações é extremamente alta (>99,99%) e encontrar o raro fenótipo Di (a+b-) é ainda mais laborioso do que a busca pelo antígeno Diª. Sabe-se ainda muito pouco sobre a frequência dos antígenos Wrª e Wrb nas diferentes populações, mas estimase que a prevalência seja de 0,01% e >99,99% respectivamente. Foram utilizadas 410 amostras de doadores de sangue e 230 amostras de pacientes para genotipagem em qPCR utilizando pool de DNA para detecção dos alelos DI*01, DI*02, DI*02.03 e DI*02.04. A amplificação individualizada foi realizada quando a reação com pool demonstrou a amplificação de um dos alelos de interesse, DI*01 ou DI*02.03. Procedeu-se também com a clonagem dos alelos após à amplificação com as amostras controle, porém, ocorreu somente a clonagem dos alelos DI*02 e DI*02.03. Os fragmentos clonados apresentaram amplificação excelente e serão utilizados como controle positivo em testes moleculares futuros. Não foi possível a clonagem do DI*01 pelo problema da zigozidade da amostra controle. Houve 100% de concordância entre o resultado da genotipagem e as informações de fenotipagem das amostras controle. O alelo DI*01 ocorreu em 0,6% dos doadores de sangue e 1,7% em afrodescendentes, que corresponde a uma frequência genotípica DI*01/DI*02 de 1,2% e 1,3% respectivamente. Procedeu-se com as análises estatísticas comparativas entre o resultado desta pesquisa e de outras na população brasileira sobre os diferentes genótipos para entender se havia uma diferença estatística considerável. Ainda que a frequência para o genótipo DI*01/DI*02 seja mais baixa em doadores e mais alta em afrodescendentes do que o publicado em outros trabalhos brasileiros, a análise dos dados demonstrou que não havia diferença estatística com a maioria deles. A incidência aumentada do alelo DI*01 na população afrodescendente demonstra o aspecto da miscigenação. Conclui-se que a metodologia proposta funciona e tem aplicabilidade imediata em doadores de sangue e na busca de fenótipos raros. A incidência do alelo para Diª em doadores de sangue está abaixo do que um estudo anterior detectou em Ribeirão Preto (COZAC, 2004), que pode ser explicado pelas diferenças no censo populacional entre os estudos e pela coleta de amostra de universitários (62%). Não foram encontrados os genótipos DI*01/DI*01, DI*02.03/DI*02.03 e DI*02.03/DI*02.04 nas populações estudadas. / This work proposed the development of a molecular methodology by Real Time-PCR (qPCR) using DNA pool for the detection of alleles that encode important antigens of the Diego blood group system. This molecular tool will be useful since the serological reagents for the detection of these antigens are scarce and, when they exist, do not allow a large scale investigation due to the low reliability and high cost. The Diego (DI) system has 22 antigens, the Diª antigen is the most important in transfusion practice. They are carried by the Band 3 protein which is the most abundant protein on the erythroid surface, about 106 copies. The antigen has a higher prevalence in american indians and asians (6%-52%), since it is considered an anthropological marker of Mongolian ancestors; however, the incidence of this antigen has increased among other populations, such as in caucasians and afrodescendants, and detected in blood donors, which may result in alloimmunization of patients and make difficult their therapeutic management. In contrast, the frequency of Dib antigen in all populations is extremely high (>99.99%) and finding the rare phenotype Di (a+b-) is even more laborious than the search for Diª antigen. The frequency of Wrª and Wrb antigens in different populations is not well-known, but it is estimated that the prevalence is 0.01% and >99.99% respectively. 410 blood donor samples and 230 patient samples were used for genotyping in qPCR using DNA pool to detect the alleles DI*01, DI*01, DI*02.03 and DI*02.04. The single amplification was performed when the pool reaction demonstrated the amplification of one of the alleles of interest, DI*01 or DI*02.03. The alleles were also cloned after the control samples amplification. Only the cloning of the DI*02 and DI*02.03 alleles occurred, they presented excellent amplification and will be used as positive controls in future molecular tests, it was not possible to clone DI*01 by the control sample zygosity though. There was 100% agreement between the genotyping results and the phenotype information of the control samples. The DI*01 allele occurred in 0,6% of the blood donors and 1,7% in afrodescendants, which corresponds to a genotypic frequency DI*01/DI*02 of 1,2% and 1,3% in respectively. The comparative statistical analyzes between this research results and others in the Brazilian population on the different genotypes was performed to understand if there was a considerable statistical difference. Although the frequency of the genotype DI*01/DI*02 is lower in donors and higher in afrodescendants than that published in other Brazilian studies, data analysis showed that there was no statistical difference with most of them. The increased incidence of the DI*01 allele in the afrodescendant population demonstrates the aspect of miscegenation. It is concluded in this work that the proposed methodology works and has immediate applicability in the screening of blood donors and search for rare phenotypes. The incidence of the allele encoding Di ª antigen in blood donors is below than previously detected in Ribeirão Preto (COZAC, 2004), which can be explained by the differences in the population census between the studies and by the sample collection of university students (62%). The genotypes DI*01/DI*01, DI*02.03/DI*02.03 and DI*02.03/DI*02.04 were not found in the populations studied.

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