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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.
81

Análises de U-Pb por LA-ICP-MS e Shrimp em zircões detríticos do complexo Passo Feio, Terreno São Gabriel implicações geotectônicas para evolução do Cinturão Dom Feliciano

Lopes, Carina Graciniana January 2014 (has links)
Idades de importância regional, ou mesmo global, foram encontradas na proveniência U-Pb de zircões detríticos de metapelitos do Complexo Passo Feio. Este complexo se localiza no Terreno São Gabriel, porção oeste do Cinturão Dom Feliciano, extremo sul da Província Mantiqueira, com evolução e metamorfismo de idade Neoproterozóica. Foram analisadas quatro amostras de metassedimentos do Complexo Passo Feio, onde foram reconhecidas populações de zircões detríticos num intervalo de idades de 803 a 3637 Ma. Todas as amostras apresentaram repetição das populações meso/paleoproterozoicas e arqueanas, e a restrição da população neoproterozóica em somente uma amostra. As idades obtidas indicam que o início da sedimentação da bacia do Complexo Passo Feio tinha como fonte principal as rochas paleoproterozóicas e arqueanas do Cráton Rio de La Plata e adjacentes, caracterizando neste período uma bacia de margem passiva. A entrada de zircões neoproterozóicos na sedimentação sugerem a evolução da bacia para um retro-arco a partir da primeira geração de arcos magmáticos com o fechamento do oceano Goiás-Farusiano. Correspondem às unidades geradas na primeira fase de convergência e acresção juvenil do Cinturão Dom Feliciano, caracterizada pela orogênese que gerou o Arco Passinho, um arco de Ilhas intra-oceânico. O pico de idades neoproterozóicas sugere uma idade mínima de evolução tectônica deste arco de 948 Ma. As idades arqueanas de 3.6 Ga representa a população de zircões detríticos mais velhas encontradas no sul do Brasil. / Ages of regional importance, or even global, were found in provenance U-Pb ages of detrital zircons from metapelites of Passo Feio Complex. This complex is located in San Gabriel Terrane, west of the Dom Feliciano Belt, southern Mantiqueira Province, with Neoproterozoic evolution and metamorphism. Four samples of metasedimentary rocks of the Passo Feio Complex were analyzed, and recognized detrital zircons populations with age range 803-3637 Ma. All analyzed samples showed repetition of meso / paleoproterozoic and Archean populations, and the restriction of Neoproterozoic population to only one sample. Ages obtained indicate that the onset of sedimentation of the Passo Feio basin had as main source the Paleoproterozoic and Archean rocks of the Rio de la Plata craton and adjacent, at this time featuring a passive margin basin. The Neoproterozoic zircons input at sedimentation suggest the evolution to a retro-arc basin, at the first generation of magmatic arcs with the closing of ocean-Farusiano Goiás. Correspond to the units generated in the first phase of convergence and accretion of juvenile Dom Feliciano Belt, characterized by orogeny that generated the Arc Passinho, an intra-oceanic arc Islands. The peak ages for Neoproterozoic suggests a minimum age of onset tectonic evolution of this arc of 948 Ma. The Archean ages of 3.6 Ga are the oldest detrital zircons population found in southern Brazil.
82

Voluntary recruitment in Scotland, 1914-1916

Young, Derek Rutherford January 2001 (has links)
The belief that Scotland showed undue patriotism by providing a high proportion of volunteers in 1914-16 needs to be looked at in a new light. While the New Armies of 1914-16 may have been volunteer in concept, they were not volunteer in actuality, and, while there was no doubt a proportion of men in Scotland, as elsewhere in the British Empire, who were prepared to come forward for purely altruistic or 'patriotic' ideals, the majority enlisted for more practical or realistic reasons. External forces either pushed or pulled those men and enticed or forced them to enlist. Previous analyses have been primarily top down. We know how many men served, and with what units, but not why. This thesis is an investigation of Scottish recruitment from the bottom up, to determine whether or not those who enlisted came from any particular section of Scottish society. This investigates and explains the driving forces behind voluntary recruitment in Scotland, August 1914 - December 1915, its methods, course taken, and its impact on the country as a whole.
83

Two Clamped Pipe Support Connections for Oil and Gas Brownfield Projects

Claycomb, Helen M 20 December 2019 (has links)
In the oil and gas industry, brownfield projects focus on the modification of or addition to an existing production facility that is fully operational and operating. Welding is typically avoided on these projects. The drilling of holes in existing primary structural elements is also prohibited. Clamped connections are often used when adding additional services in a brownfield project. There are different types of clamped connections utilized when a new structural support must be attached to an existing vertical structural pipe. The short bolt clamped connection is a well-established connection and typically used on offshore projects. The U-bolt clamped connection is an alternative connection, although its use in the offshore oil and gas industry is not as well documented. The main drawback to using the U-bolt clamp connection is the lack of a well researched and vetted design methodology. A preliminary analysis methodology is proposed in this thesis. The material, fabrication, installation, and maintenance of both the short bolt connection and U-bolt connection will also be discussed. The following thesis will end with recommendations for moving forward.
84

U snRNAの核外輸送複合体の形成に関与する因子の解析

和泉, 光人 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18114号 / 理博第3992号 / 新制||理||1576(附属図書館) / 30972 / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 大野 睦人, 教授 青山 卓史, 教授 高田 彰二 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
85

A framework for determining the impact of deferred maintenance and/or obsolescence of a highway system

Chasey, Allan D. 06 June 2008 (has links)
In the early 1980's, the decline in the U.S. infrastructure was highlighted by a report entitled America in Ruins: Beyond the Public Works Pork Barrel. A series of reports followed trying to assess the condition of the infrastructure. One of these reports, Fragile Foundations, assigned grades to the various infrastructure systems and concluded that "the quality of America's infrastructure is barely adequate to fulfill current requirements and insufficient to meet the demands of future economic growth and development." This research develops a framework to account for the impact of deferred highway maintenance and/or construction on user and non-user benefits. This will aid the decision-making process and help guide the effective use of scarce financial resources. The framework proposes the concept of a Comprehensive Level of Service for highways using a combination of both maintenance (Level of Operation) and capacity (Level of Availability) indicators. Highways, like equipment, are affected by deterioration and obsolescence, obsolescence being the inability to function as designed. Deterioration, defining the physical level of service, comes from the aging of physical materials over time. Obsolescence, defining the functional level of service, comes from increased usage. Together, they result in overcrowding, congestion and increased economic costs to both users and non-users. A mathematical model is developed that allows simulation of the impact of deferred highway maintenance based on the concept of a Comprehensive Level of Service. System dynamics is the simulation methodology utilized as it allows incorporation of social, technical, economic and political issues into a laboratory setting to analyze change. The framework, permitting evaluation of the future implications of current policy decisions, is demonstrated through scenario analysis. The scenarios include an analysis of various highway maintenance investment levels and of the trade-off between highway maintenance and highway improvement. These scenarios demonstrate the impact of maintenance and construction investments on a highway system through a user and non-user benefit analysis. / Ph. D.
86

Ch3-IDTIMS-Ages

Wai Kehadeezbah Allen (14671736) 17 May 2024 (has links)
<p>This dataset contains two datasets:</p> <p><br></p> <p>1) 16SI166 Bedrock Sample from the Ruby Range Batholith sampled by Steve Israel while he was at the Yukon Geological Survey and was Analyzed by Jim Crowely at Boise State University. Additional sheets show progression from LA-ICPMS methods to ID-TIMS and include CL imaging for individual grains</p> <p><br></p> <p>2) 09_CONG Tephra Sample from the Eastern Alaska Range that was dated as apart of the NG1 measured section. This sample was collected by Jeffrey Benowitz and analyzed by  Joshua Davies at the Département des sciences de la Terre et de l'atmosphère, Université du Québec à Montréal </p>
87

Detrital zircon U-Pb and (U-Th)/He geo-thermochronometry and submarine turbidite fan development in the Mio-Pliocene Gulf of California, Fish Creek-Vallecito Basin, southern California

Cloos, Michael Ethan 27 October 2014 (has links)
The Fish Creek-Vallecito Basin exposes an archive of sediment related to early rifting of the Gulf of California beginning at 8.0 Ma followed by Colorado River delta progradation from 5.3-3.0 Ma. Mio-Pliocene deposits from the Fish Creek-Vallecito Basin of southern California and a sample from the modern Colorado River delta were analyzed through detrital zircon U-Pb (n=1996) and (U-Th)/He (n=280) double-dating in order to better constrain sediment provenance, hinterland exhumation, and Colorado River evolution. Coupling this dataset with outcrop study of the first Colorado River-sourced turbidites into the basin at 5.3 Ma, allows for evolution of the Colorado River system to be viewed from a source-to-sink perspective. Detrital zircon U-Pb and (U-Th)/He (ZHe) ages obtained in this study suggest earliest derivation of sediment was from the Peninsular Ranges followed by more distant sediment sourcing from the Colorado River. Initial Colorado River-sourced deposits show Yavapai-Mazatzal U-Pb ages with Laramide ZHe ages suggesting that the river was sourcing from Laramide basement cored uplifts at the onset of deposition into the Gulf of California, supporting a top-down model of river evolution. An increased percentage of Grenville U-Pb age grains as well as a wider range of ZHe ages associated with western US basement-derived zircon from a modern Colorado River delta sample indicate erosion into older stratigraphic units through time which is consistent with deep erosion on the Colorado Plateau since ~6 Ma. Vertically measured sedimentology logs through the Wind Caves Member, the first Colorado River-sourced unit deposited, were used to determine slope and basin floor architecture as the Colorado River and delta dispersed subaqueous sediment gravity flows into the marine Gulf. Measured sections arrayed along depositional strike show a 4.5 km wide pod of sand-rich turbidites that were delivered through a broad Fish Creek exit point from the paleo-Colorado shelf. The vertical sedimentation trend is one showing thick bedded, amalgamated channelized and sheet-like sandstones initially, shifting to thinnerbedded sheets and more isolated channels higher in the increasingly muddy section. The facies variability up section is interpreted as a change from a submarine basin floor fan to a lower slope environment as the Colorado River prograded its delta into the Gulf. / text
88

Framtidens krav på byggnaders klimatskal : – En utredning åt Sigma Civil AB

Garzon Gamboa, Alirio January 2016 (has links)
Samtidigt som kraven på energieffektivitet inom byggbranschen blir allt hårdare har klimatskalets utformning stor betydelse. Författarens uppgift är att utreda åt Sigma Civil AB hur ett verktyg som beräknar U-värden utformas samt att med hjälp av den göra en jämförande studie på yttertak och ytterväggar, med avseende på klimatskalets påfrestningar.   Andra delar som ingår i klimatskalet är grundkonstruktioner men eftersom det är ett arbete som omfattar 10 veckor avgränsas arbetet till yttertak och ytterväggar. För att arbetet skulle kunna utföras på ett bra sätt som möjligt har författaren genom litteraturstudier i form av böcker, internetbaserade sidor och olika rapporter tagit del av information som hjälpt både vid utförande av beräkningsverktyget men också vid jämförelsen av byggdelar.   Resultatet för den här studien visade att koljerntekniken på grund av sin täta struktur fungerar bäst av de takkonstruktioner som jämfördes i studien. I den analys som gjordes för väggkonstruktioner var det en yttervägg med PIR-isolering som klarade sig bäst. En av de slutsatser som jag drar av studien är att bättre isoleringsmaterial krävs för att klara framtidens krav på klimatskalet. Det andra som är viktigt att ta med sig från studien är att byggbranschen bör vara öppen för nya tekniker, som till exempel koljerntekniken och PIR-isoleringen. / While requirements increasingly become harder in the construction industry that it will be built energy efficient, buildings envelope design plays a very large part. My task is to investigate for Sigma Civil AB how a tool that calculates the U-value is formed as well as using it to make a comparative study on the roof and exterior wall, with respect for the building envelope external influences.   Another part of the building envelope is the basic designs, but because it is a work where is only 10 weeks I need to delimit to the roof and exterior walls. In order that the work could be carried out in the best possible way I did literature study in form of books, internet based pages and various reports to receive information that helped me both when I was performing the calculation tool but also doing the comparison of the building parts.   The result of this study showed that the koljern-technique because of its dense structure works best as a roof, compared to the other roofs in the study. In the analysis made for wall constructions, it was an exterior wall with PIR-insulation that worked best. One of the conclusions that I draw from this study is that better insulation needs to meet future requirements for the building envelope. The other thing that is important to take from the study is that the construction industry should be open to new technologies, such as the koljern-technique and PIR-insulation.
89

Ett gott värdskap är ett värdskap som berör

Göran Rodell, Annika January 2014 (has links)
Kan ett värdskap som är kommersiellt även vara genuint välkomnande och kan man idag på allvar vinna fördelar på en konkurrensutsatt marknad utan att erbjuda ett genuint värdskap? Bakgrunden till detta arbete är det etableringsprojektet med titeln: "Värdskap och ledarskapsom berör – ett konkurrensmedel?" som finansierades av KK-stiftelsen (Stiftelsen för Kunskap och Kompetens) år 2010. Representanter från besöksnäringen på lokal, regional och nationell nivå möttes på två välrenommerade landsortshotell för att lägga grunden till ett större gemensamt forskningsprojekt. Inga ytterligare medel tilldelades dock projektet varför delar av det stora materialet från studien nu redovisas i denna c-uppsats. I projektet användes Teori U som både teoretisk utgångspunkt och processmetod. Syftet för uppsatsen handlar för det första om att undersöka metodens användbarhet i att främja branschens egen förståelse för vad ett gott värdskap är. För det andra handlar det om att undersöka hur man kan frigöra implicit kunskap och samskapa nya insikter om ett gott värdskap samt hur dessa i så fall kan kopplas till praktiken. I studien genomfördes två workshops, på två hotell med olika deltagare. Workshoparna, som filmades, varade ett dygn (från lunch till lunch). Ur det empiriska materialet utmejslades fem teman för ett värdskap som berör: ledarskap, passion, mod, självinsikt och grundläggandevärderingar. I bägge workshops talade man om att det i branschen behövs ett paradigmskifte från kunskapssamhälle till relationssamhälle. Deltagarna uttryckte att de upplever en avsaknad av kunskap om immateriella känslomässiga värden, om vad som sker i själva mötet. Resultatet pekar på att vi behöver undersöka vad som händer om vi utbildar i det som gör oss mer närvarande, autentiska och medvetna. Skulle det kunna vara ett sätt att skapa innovation i bemötande? / KK-stiftelsen Etableringsprojekt beviljat 2010 "Värdskap och ledarskap som berör- ett konkurrensmedel?"
90

Análise neutrônica e especificação técnica para o combustível a dispersão UMo-Al com adição de veneno queimável / Neutronic analysis and technical specification for a UMo-Al dispersion fuel with burnable poison addition

Muniz, Rafael Oliveira Rondon 03 December 2015 (has links)
Este trabalho apresenta a análise neutrônica do combustível a dispersão de UMo-Al em relação ao aumento da densidade de urânio e faz uma comparação com o combustível de U3Si2-Al. Neste estudo, a densidade de urânio do U3Si2-Al é variada de 3,0 à 5,5 gU/cm3 e a do UMo-Al entre 4,0 à 7,5 gU/cm3 e com a porcentagem em massa de molibdênio com 7 e 10 %. Neste trabalho também é proposta a aplicação de veneno queimável metálico no cerne do combustível de UMo-Al, uma vez que este combustível é metálico e é analisada a utilização de gadolínio (Gd) e európio (Eu) como veneno queimável. A utilização do Gd como veneno queimável foi analisada com o fator de multiplicação infinito (k&infin;) através do programa celular HRC desenvolvido pelo IPEN e composto pelos códigos HAMMERTECHNION para a analise de célula, ROLAIDS para o cálculo de auto blindagem dos actinídeos e CINDER-2 empregado para a fissão e transmutação dos actinídeos. O núcleo do reator simulado foi similar ao do RMB (Reator Multipropósito Brasileiro) composto por um arranjo de 5x5 posições com 23 elementos combustíveis e dois blocos de alumínio. Para o európio, foram utilizados os programas SERPENT e CITATION. Os cálculos de queima foram realizados considerando uma potência de 30 MW durante três ciclos do RMB de 97 dias. Os resultados obtidos mostram que a porcentagem em massa do molibdênio têm uma grande influência no comportamento neutrônico devido a seção de choque de absorção do molibdênio ser considerável. Portanto, foi escolhida a porcentagem de 7 % de Mo para os estudos com veneno queimável. Para o núcleo proposto, o európio mostrou-se melhor, pois apresenta uma queima mais gradual que o gadolínio. Foi realizada uma simulação com o programa SERPENT com adição de 6 % de silício, o que mostrou que a adição de Si não causa mudança significativa no ciclo de operação do reator. Para validação da metodologia de cálculo, foi elaborada uma especificação técnica e fabricadas 12 miniplacas combustíveis de UMo-Al sem veneno queimável. As miniplacas foram irradiadas no núcleo do reator IPEN/MB-01, em quatro configurações de núcleo, para obtenção da reatividade inserida. Os resultados simulados obtidos para a inserção de reatividade pelas miniplacas nos diversos núcleos analisados apresentaram alta concordância com os resultados experimentais. / This work presents the neutronic analysis of the UMo-Al dispersion fuel concerning uranium density increase and shows comparisons relatively to the U3Si2-Al fuel. The U3Si2-Al uranium density varied from 3.0 to 5.5 gU/cm3 while that of UMo-Al fuel varied from 4.0 to 7.5 gU/cm3. The molybdenum mass content in the former case varies from 7 to 10 % in mass. Here, it is also proposed the utilization of burnable poison nuclides in the UMo-Al fuel meat. Since the fuel is metallic, gadolinium and europium were chosen as candidates to cope with this task. A recently developed cell code at IPEN (HRC) composed of the coupling of the codes HAMMER-TECHNION for the cell analysis, ROLAIDS for the actinide self-shielding calculations and CINDER-2 for the actinide and fission transmutation was employed for the neutronic analyses of UMo-Al. The simulated reactor core was similar to the one of RMB (Brazilian Multipurpose Reactor) composed of an array of 5x5 positions with 23 fuel elements and 2 aluminum blocks. A second analysis of the europium case employed the SERPENTE and CITATION codes. The burnup calculations were performed considering a power of 30 MW during three cycles of RMB 97 days. The analyses revealed that the molybdenum content has a great impact in the core reactivity due to its high absorption cross section. A value of 7 % was found adequate for the molybdenum mass content. The analyses also reveal that europium is a better burnable poison than gadolinium for the core cycle length and power level under consideration. It was realized a simulation with the computer code SERPENT with addition of 6 % silicon in UMo-Al fuel. The silicon does not change significantly the reactor operation cycle. To validate the calculation methodology it was developed a technical specification and fabricated 12 UMo-Al fuel miniplates without burnable poison. The miniplates were irradiated in the IPEN-MB/01 reactor core for four core configurations, in order to obtain the inserted reactivity. The simulated results for the reactivity insertion by the fuel miniplates in the analyzed cores showed high agreement with the experimental results.

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