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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.
241

Dividing lines, converging aims : a moral analysis of micro-regionalism in Ghana and Côte d'Ivoire

Whiteford, Sarah January 2011 (has links)
This thesis provides a moral analysis of micro-regional forces in Ghana and Côte d’Ivoire, using the framework of the New Regionalism Approach (NRA). It presents an original contribution to the field through the addition of the Ghanaian-Ivoirian case study, as well as a unique application of Martha Nussbaum’s Capabilities Approach to the NRA. In an attempt to counter the view that borders in Africa are artificial, arbitrary and the result of colonial imposition, this research employs the Capabilities Approach, providing a narrative of both positive and negative impacts resulting from the opportunity created by borders in West Africa. The way in which the Ghanaian-Ivoirian border is used by individuals in their security strategies in the face of economic deprivation and physical threats represents a positive impact of borders. Conversely, the role of borders in the continued prevalence of human trafficking in West Africa is also questioned in this piece, providing a balanced account of the impact of borders. This research concludes that the Ghanaian-Ivoirian border presents opportunities that can be exploited to both positive and negative ends at the micro-regional level. This interpretation suggests that any complete account of borders in West Africa more broadly ought to employ a moral framework in addition to a multi-levelled scale of analysis.
242

Mechanism of failure by hydrogen-induced cracking in pipeline steels

2015 August 1900 (has links)
Pipeline steels that carry oil and natural gas in severe environments suffer from two important modes of failure: stress corrosion cracking (SCC) and hydrogen-induced cracking (HIC). The SCC has been studied extensively in the literature; however, HIC phenomenon in pipeline steels is less investigated by researchers. Nevertheless, HIC is recognized as the most important damage mode in sour environment. Hydrogen atoms produced due to surface corrosion of the steel diffuse into it through microstructural defects. When a critical amount of hydrogen is accumulated in such defects, HIC cracks initiate and propagate. The main objectives of this thesis are to find the HIC crack nucleation and propagation sites, evaluate a role of texture and grain boundary character distribution in crack growth and finally establish the effect of different microstructural parameters contributing to the HIC related failure in pipeline steel. In this thesis, HIC standard test and electrochemical hydrogen-charging experiments were used to induce HIC cracks in pipeline steels. HIC cracks at the cross section of tested samples were observed using scanning electron microscope (SEM). The SEM observations clearly indicate that the investigated X60 and X70 steels are susceptible to HIC while the X60SS steel showed a higher resistance to HIC. This experiment also proved that the X70 steel has higher susceptibility to HIC than the other investigated steel. Energy dispersive spectroscopic (EDS) analyses indicated that two types of inclusion namely manganese sulfide and carbonitiride precipitates serve as crack nucleation sites. HIC cracks were observed to propagate at the center of cross section where the segregation of some elements such as carbon and manganese occurred. Moreover, two other experiments were carried out in order to evaluate the capability of pipeline steels for hydrogen-trapping. The first test, hydrogen-permeation experiment, showed that all pipeline steel specimens, such as X70, X60 and X60SS steels, contain both reversible and irreversible hydrogen traps. However, the density of traps at the center of cross section was higher than other regions in all tested specimens. The hydrogen-discharging experiments also showed that all specimens keep a considerable amount of hydrogen inside their traps. The hydrogen traps, based on their binding energy with the metal matrix, are categorized as reversible (weak) and irreversible (strong) traps and the roles of each type of traps are explained. Electron backscatter diffraction (EBSD) measurements were done along the HIC crack in X70 steel after standard HIC test. The results showed that the {100} texture was strong while the {111} texture was weak. Some special texture components, such as the {110}, {332} and {112}, were observed after the HIC crack-stoppage. EBSD results also documented that fine grain colonies were prone to intergranular HIC crack propagation and IPF and PF, calculated in both sides of HIC cracks, showed the preferences of ND||<100> orientation. Both susceptible X60 and non-susceptible X60SS steel to HIC were compared based on the EBSD results. It was observed that the high amount of recrystallization fraction with no stored energy is one of the main reasons for a higher HIC resistance of X60SS steel to HIC. Moreover, Kernel Average Misorientation (KAM) data showed that the deformation is more concentrated in the as-received and HIC tested X60 specimens. The effect of hydrogen-charging during tensile/fatigue loading of X60SS steel was studied and it was observed that some HIC cracks at the cross section of X60SS steel were appeared after hydrogen-charging at stresses below the yield stress. Experiments were carried out to understand the effect of cold-rolling and annealing on HIC susceptibility in pipeline steels. The results documented that the {100} dominant texture is more pronounced in 50% and 90% cold-rolled and annealed specimens. The effect of different factors such as KAM degree and recrystallized fraction affecting HIC susceptibility on cold-rolled and annealed specimens was investigated. The obtained results showed that the cold-rolling and annealing process may not be considered as an effective method to increase HIC resistance in pipeline steels.
243

O turismo, o reencontro e a redescoberta da região das Missões / O turismo, o reencontro e a redescoberta da região das Missões

Nogueira, Carmen Regina Dorneles 12 April 2007 (has links)
O presente trabalho consta da descrição explicativa dos processos de ocupação da Região das Missões Jesuítico-Guarani, que contribuíram para que a mesma tenha se constituído hoje, em uma \"Região Turística Transfronteiriça\". Sua configuração atual resulta do processo de expansão colonial ibérica e das relações que se estabeleceram entre os colonizadores e os habitantes locais e, entre ambos e o ambiente com seus recursos. Constatou-se que sua singularidade é uma conseqüência dos processos históricos que são evidenciados em três períodos bem característicos: Período pré-jesuítico: caracterizado pela organização dos Guarani em pequenas comunidades, que ocupavam os lugares com solo fértil para a prática da agricultura, como as várzeas dos grandes rios, vales e lugares com matas. Mantinham uma relação ecológica com o território, retirando da terra somente o necessário à sua sobrevivência. Período jesuítico: no qual houve a ?redução? da comunidade indígena, que passou a manter uma nova forma de se relacionar com o território; implantando, ao mesmo tempo, um sistema de produção coletivo-complementar, aliado a um sistema comercial responsável por enviar, para a Europa, produtos como sebo, erva-mate, algodão, chifre e couro. Período pós-jesuítico: vai, desde a derrocada das Missões até os dias de hoje. Caracterizado pelos desajustes sociais, econômicos e ambientais, frutos das expansões agropecuárias, mineiras e industrial, baseada em um modelo que se caracterizou pelo deterioramento do meio ambiente como custo necessário ao progresso, não se mostrou viável para resolver os problemas econômicos e sociais da população regional. Esse período caracteriza-se também pela busca de soluções para os problemas regionais, através da dinamização do uso público do rico patrimônio histórico-cultural através do turismo. Surgem projetos e programas voltados para a dinamização do turismo regional, no entanto os mesmos não atingiram totalmente os objetivos a que se propuseram. O uso do método evolutivo histórico, a partir da pesquisa bibliográfica e da pesquisa de campo, com observação direta sistematizada e realização de entrevistas, proporcionou o alcance dos objetivos de: analisar a importância das Missões Jesuíticas na consolidação das fronteiras do sul do Brasil; analisar a situação dos sítios arqueológicos das antigas reduções jesuítico-Guarani, avaliar a importância dos remanescentes arquitetônicos das reduções como potencial turístico; analisar os programas e projetos propostos para a Região das Missões em relação ao turismo, além de fornecer subsídios que possam contribuir para a implementação, intensificação e expansão da atividade turística regional. / The present work is a descriptive explanation of the processes of the occupation of the Jesuit-Guarani Missions, which ended up transforming it into a tourist atiraction beyond borders. Its present-day status is a result of the relations which have been established between the Iberian sett and the Local inhabitants and among themselves, and the environment with its resources. It can be said that its singularity is a consequence of the history´s processes which are evident in three welI-defined periods: Pre-Jesuit period it is characterized by the organization of the Guarani Indians in small communities which occupied places having a fertile soil, good for agriculture, like the flat lands along rivers, valleys and woodland. They maintained an ecological relation with lhe territory, extracting from the soil only the every day necessities for their survival. Jesuit Period: in which there was a \"reduction\" of the Indian community and which started a new way of interaction with the territory, irnplementing, at the same time, a coilective cornplementary production system together with a business-like system responsible for sending to Europe products like tallow, mate, cotton, horn and leather. Post-Jesuit Period: beginn ing since the destruction of the Missions till nowadays. lt is characterized by social , economical and environmental due to agronornic , mineral and industrial expansion, based on a model which is characterized by the deterioration of the environment as a by-product of progress, not being able to solve the economic and social problems of the regional population. This period is also characterized because of a search for solutions for regional problems, through a dynarnic use of its rich cultural-historical touristic patrirnony. The use of lhe historical evolutionary rnethod, through bibliographic and field research, with direct and systematic observation and interviews Ied to the following objectives: to analyze the irnportance of lhe Jesuit Missions in the consolidation of the Southern Brazilian boundaries; to analyze the situation of the archeological sites of the former Jesuit-Guarani reductions, to evaluate the importance of lhe architectonic remainings of the old Jesuit-Guarani reductions as a touristic potential; tlo analyze the prograrns and the projects destined to the Missions Region as far as tourism is concerned, besides best subsidies which can contribute in the implementation, intensification and expansion of lhe regional tourism activity.
244

O turismo, o reencontro e a redescoberta da região das Missões / O turismo, o reencontro e a redescoberta da região das Missões

Carmen Regina Dorneles Nogueira 12 April 2007 (has links)
O presente trabalho consta da descrição explicativa dos processos de ocupação da Região das Missões Jesuítico-Guarani, que contribuíram para que a mesma tenha se constituído hoje, em uma \"Região Turística Transfronteiriça\". Sua configuração atual resulta do processo de expansão colonial ibérica e das relações que se estabeleceram entre os colonizadores e os habitantes locais e, entre ambos e o ambiente com seus recursos. Constatou-se que sua singularidade é uma conseqüência dos processos históricos que são evidenciados em três períodos bem característicos: Período pré-jesuítico: caracterizado pela organização dos Guarani em pequenas comunidades, que ocupavam os lugares com solo fértil para a prática da agricultura, como as várzeas dos grandes rios, vales e lugares com matas. Mantinham uma relação ecológica com o território, retirando da terra somente o necessário à sua sobrevivência. Período jesuítico: no qual houve a ?redução? da comunidade indígena, que passou a manter uma nova forma de se relacionar com o território; implantando, ao mesmo tempo, um sistema de produção coletivo-complementar, aliado a um sistema comercial responsável por enviar, para a Europa, produtos como sebo, erva-mate, algodão, chifre e couro. Período pós-jesuítico: vai, desde a derrocada das Missões até os dias de hoje. Caracterizado pelos desajustes sociais, econômicos e ambientais, frutos das expansões agropecuárias, mineiras e industrial, baseada em um modelo que se caracterizou pelo deterioramento do meio ambiente como custo necessário ao progresso, não se mostrou viável para resolver os problemas econômicos e sociais da população regional. Esse período caracteriza-se também pela busca de soluções para os problemas regionais, através da dinamização do uso público do rico patrimônio histórico-cultural através do turismo. Surgem projetos e programas voltados para a dinamização do turismo regional, no entanto os mesmos não atingiram totalmente os objetivos a que se propuseram. O uso do método evolutivo histórico, a partir da pesquisa bibliográfica e da pesquisa de campo, com observação direta sistematizada e realização de entrevistas, proporcionou o alcance dos objetivos de: analisar a importância das Missões Jesuíticas na consolidação das fronteiras do sul do Brasil; analisar a situação dos sítios arqueológicos das antigas reduções jesuítico-Guarani, avaliar a importância dos remanescentes arquitetônicos das reduções como potencial turístico; analisar os programas e projetos propostos para a Região das Missões em relação ao turismo, além de fornecer subsídios que possam contribuir para a implementação, intensificação e expansão da atividade turística regional. / The present work is a descriptive explanation of the processes of the occupation of the Jesuit-Guarani Missions, which ended up transforming it into a tourist atiraction beyond borders. Its present-day status is a result of the relations which have been established between the Iberian sett and the Local inhabitants and among themselves, and the environment with its resources. It can be said that its singularity is a consequence of the history´s processes which are evident in three welI-defined periods: Pre-Jesuit period it is characterized by the organization of the Guarani Indians in small communities which occupied places having a fertile soil, good for agriculture, like the flat lands along rivers, valleys and woodland. They maintained an ecological relation with lhe territory, extracting from the soil only the every day necessities for their survival. Jesuit Period: in which there was a \"reduction\" of the Indian community and which started a new way of interaction with the territory, irnplementing, at the same time, a coilective cornplementary production system together with a business-like system responsible for sending to Europe products like tallow, mate, cotton, horn and leather. Post-Jesuit Period: beginn ing since the destruction of the Missions till nowadays. lt is characterized by social , economical and environmental due to agronornic , mineral and industrial expansion, based on a model which is characterized by the deterioration of the environment as a by-product of progress, not being able to solve the economic and social problems of the regional population. This period is also characterized because of a search for solutions for regional problems, through a dynarnic use of its rich cultural-historical touristic patrirnony. The use of lhe historical evolutionary rnethod, through bibliographic and field research, with direct and systematic observation and interviews Ied to the following objectives: to analyze the irnportance of lhe Jesuit Missions in the consolidation of the Southern Brazilian boundaries; to analyze the situation of the archeological sites of the former Jesuit-Guarani reductions, to evaluate the importance of lhe architectonic remainings of the old Jesuit-Guarani reductions as a touristic potential; tlo analyze the prograrns and the projects destined to the Missions Region as far as tourism is concerned, besides best subsidies which can contribute in the implementation, intensification and expansion of lhe regional tourism activity.
245

Crossing Lines : A study about lines and their translations

La Marca, Anna January 2021 (has links)
Lines are everywhere and as humans we produce lines all the time. In this project I used the line as a method, a metaphor, and a material to explore what are the elements that influence and condition the way we move and behave around different spaces. Lines can be read as many things and for this project I choose to work with lines that could be understood as boundaries and limits. How do we deal with lines in our everyday life? How do lines and bodies influence each other? How is the space choreographed and experienced according to the boundaries that exist in it?   However not all boundaries are made of matter. In fact, some of them are invisible and manifest as prohibitions, regulations, prejudice, or just cultural norms. These limits can also be understood as non-matter lines that have an impact on one's experiences. Through several explorations, the project proposes an installation that seeks to embody the spatial boundaries that cannot always be seen. Using light and sound as catalyzers for these experiences, the installation is a reflection on what happens when we meet those invisible lines, how they have the power to change our usual path and to make us move differently around a space.
246

Intermediate temperature grain boundary embrittlement in nickel-base weld metals

Nissley, Nathan E. 22 September 2006 (has links)
No description available.
247

The Northern Territories dispute between Japan and the Soviet Union: from rivalry to rapprochement

Clements, John Patrick 08 April 2009 (has links)
A restrained relationship between the Soviet Union and Japan, great military and economic powers and geographically close neighbors in Northeast Asia, is an international anomaly of considerable magnitude. Resolution of this anomaly has been delayed for the last forty-five years by several factors, but none more so than that of what has commonly been referred to as the "Northern Territories" dispute. The territorial dispute of the Northern Territories, otherwise known as the four islands of Etorofu, Kunashiri, Shikotan and the Habomai group is discussed in relation to both the historical and contemporary policies of Japan and the USSR. According to the Soviet’s perspective these islands belong to them on the basis of their military annexation in 1945. Japan fails to recognize this sovereignty, hence, leaving Japan and the USSR in a technical state of war, impeding normal Soviet-Japanese relations. Presently, Gorbachev’s policy of Perestroika has indicated the possibility of concessions and rapprochement over the islands after forty-five years of consistent deadlock. This new Soviet policy is aimed at improving relations with Japan and moving toward more economic and political cooperation, allowing the Soviets to participate in the economic prosperity of the Pacific Basin. However, Japan refuses to comply with such concessions, and demands Soviet recognition of the territorial issue prior to negotiations. Furthermore, opposition toward such conciliation exists in the USSR since any concession might lead China and other nations to press their own territorial claims. Thus, the political, economic and strategic implications of the Northern Territories problem ensures that it will remain a critical contemporary geopolitical issue in Northeast Asia. / Master of Science
248

Grain boundary mobility of KCl.

Yan, Man F. January 1976 (has links)
Thesis: Sc. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 1976 / Vita. / Bibliography: leaves 231-251. / Sc. D. / Sc. D. Massachusetts Institute of Technology, Department of Materials Science and Engineering
249

A Case Study on the Extraction of the Natural Cities from Nightlight Image of the United States of America

LIU, QINGLING January 2013 (has links)
The boundaries of the cities are not immutable, they can be changed. With the development of the economies and societies, the population and pollution of cities are increasing. Some urban areas are expanding with more population or other dynamics of urbanization, while other urban areas are reducing with the changing of the dynamics. Therefore, detecting urban areas or delineating the boundaries of the cities is one of the most important steps for urban studies, which is closely related to human settlements and human activities. Remote sensing data (RS) is widely used to monitor and detect land use and land cover on the surface of the earth. But the extraction of urban areas from the ordinary RS data is not easy work. The Operational Linescan System (OLS) is the sensors of the Defense Meteorological Satellite Program (DMSP). The nighttime lights from the DMSP/OLS provide worldwide remotely sensed data to analyze long-term light emissions which are closely related to human activities. But the nighttime lights imagery data contains inherent errors. Therefore, the approaches to calibrate the data and extract the urban areas from the data are complicated. The long-term objective of this thesis is to delineate the boundaries of the natural cities of the continental United States of America (USA) from 1992 to 2010 of nightlight imagery data with all the different satellites. In this thesis, the coefficients for the intercalibration of the nightlight imagery data have been calculated based on the method developed by Elvidge, et al. (2009), but the coefficients are new and available. The approach used to determine the most appropriate threshold value is very important to eliminate the possible data error. The method to offset this possible error and delineate the boundaries of the cities from nightlight imagery data is the head/tail breaks classification, which is proposed by Jiang (2012b). The head/tail breaks classification is also useful for finding the ht-index of the extracted natural cities which is developed by Jiang and Yin (2013). The ht-index is an indicator of the underlying hierarchy of the data. The results of this study can be divided into two categories. In the first, the achieved coefficients for the intercalibration of nightlight images of the continental USA are shown in a table, and the achieved data of the urban areas are stored in a data archive. In the second, the different threshold values of the uncalibrated images and the individual threshold value of the calibrated images are shown in tables, and the results of the head/tail breaks classification and power law test are also drawn. The results show that the acquired natural cities obey the power law distribution. And the results also confirm that the head/tail breaks classification is available for finding a suitable threshold value for the nightlight imagery data. Key words: cities’ boundaries; DMSP/OLS; head/tail breaks classification; nighttime lights; power law; urban areas
250

The current-voltage and noise properties of high temperature superconductor SNS and grain boundary junctions

McGordon, Andrew January 1999 (has links)
No description available.

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