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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.
61

Representação do componente de software na FARCSoft: ferramenta de apoio à reutilização de componentes de software. / Software component representation in the FARCSoft: software component reuse suport tool.

Rossi, Ana Claudia 16 April 2004 (has links)
Atualmente, as organizações estão cada vez mais dependentes de sistemas de informação para a realização de seus negócios. Com isso, uma das preocupações, na área de desenvolvimento de software, é a obtenção cada vez mais rápida de sistemas que atendam as necessidades atuais e que sejam flexíveis para acompanhar as mudanças de tecnologia e práticas de negócio. A reutilização de componentes de software tem sido considerada uma das formas para obter redução dos custos e do tempo de desenvolvimento e aumento da produtividade e da qualidade do produto de software. A implantação da reutilização de componentes é baseada em três elementos principais que consistem de um processo de desenvolvimento voltado para reutilização, de uma ferramenta adequada e de uma cultura de projeto. A ferramenta, por sua vez, deve ter a capacidade de armazenar os componentes e de fornecer recursos para uma recuperação eficiente. O objetivo deste trabalho é definir uma representação de componentes em um repositório, a qual permita armazenar diferentes tipos de componentes de software. Para isso, foi especificada a Ferramenta de Apoio à Reutilização de Componentes de Software, denominada de – FARCSoft, que deve fornecer suporte à reutilização de componentes de software. Esta ferramenta apresenta recursos para armazenar, gerenciar, buscar e recuperar os componentes do seu repositório. A capacidade de representação foi avaliada por meio de um conjunto de componentes de tipos, porte e tecnologia diversos, os quais foram modelados e catalogados. / Nowadays, organizations increasingly depend on information systems to carry out their business. Thus, one of the preoccupations in the software development area is the need to obtain systems faster and faster, attending to current needs and sufficiently flexible to accompany changes in technology and business practices. Software component reuse has been considered one of the ways to reduce costs and development time and increase productivity and software quality. The implantation of component reuse is based on three main elements, which consist in a development process oriented towards reuse, an adequate tool and a project culture. The tool, in turn, must be able to store the components and to supply resources for the sake of efficient recovery. This study aims to define a component representation in a repository, which allows for the storage of different kinds of software components. For this purpose, a Software Component Reuse Support Tool was specified, called FARCSoft, which should support the reuse of software components. This tool presents resources to store, manage, search and recover the components of a repository. Representation capacity was evaluated by means of a set of components with different types, sizes and technologies, which were modeled and catalogued.
62

Avaliação da alteração das propriedades da pasta de cimento em ambiente de repositório / Assessment of cement paste properties changes in repository environment

Ferreira, Eduardo Gurzoni Alvares 30 April 2013 (has links)
Pasta de cimento é um material comum em repositórios para rejeitos radioativos, atuando como material estrutural e de imobilização. Sua utilização como material de preenchimento em um repositório tipo poço tubular profundo para fontes seladas, no entanto, requer um maior tempo de vida útil do material. O conhecimento de seu comportamento em longo prazo é necessário para garantir a segurança da instalação em milhares de anos. O presente trabalho avaliou as alterações na pasta de cimento induzidas por fatores de degradação, como ataque de agentes agressivos, alta temperatura e presença de campo de radiação. Corpos de prova (cps) de pasta de cimento foram submetidos a ensaios acelerados de degradação e os efeitos deletérios foram avaliados por meio de ensaios de resistência mecânica, variação dimensional, lixiviação/penetração de íons, DRX, TGA e MEV. Observou-se que a hidratação dos cps foi beneficiada pela imersão (em água destilada ou em solução salina) e alta temperatura, resultando em uma resistência maior. O armazenamento à seco prejudicou a hidratação, mantendo a resistência mais baixa. O tempo de imersão e a irradiação não foram capazes de alterar a mineralogia e a resistência da pasta de cimento. / Cement paste is widely used in repositories for radioactive wastes, acting as structural and immobilization material. However, its use as backfill material in boreholes for sealed sources requires a longer service life of this material. The assessment of the cement paste behavior in long term is needed to improve the confidence that the material will perform as required during the service life of the facility. This research evaluated the changes in cement paste induced by degradation parameters. Portland cement paste specimens (cps) were submitted to accelerated degradation tests and the damage effects was evaluated by mechanical strength, variation of sample mass and volume, leaching/penetration of ions, XRD, TGA and SEM. It was observed that cps hydration was benefited by immersion (in distilled water or salt solution) and high temperatures, resulting in a higher strength. Dry storage, however, influenced the hydration process and maintained strength lower. Time of treatment and irradiation were not able to alter mineralogy and durability of cement paste.
63

Vetenskaplig kommunikation inom kemi och ekonomi : ett polskt perspektiv. / Scholarly communication activities in the fields of chemistry and economics : A Polish perspective.

Szuflita, Magdalena Anna January 2014 (has links)
This study examines the scholarly communication activities in two scientific fields, chemistry and economics, in a Polish context. The dissertation aims at investigating what characterises the publishing choices of researchers and what supplementary forms for the dissemination of research output are used by scholars. In addition, the paper is looking into what are the views and awareness of open access and institutional repositories within this scientific community. This thesis gives the results of semi-structured interviews and an online survey at two academic faculties at a Polish technical university. As its theoretical framework, the study uses Whitley’s theory of the intellectual and social organisation of academic fields and Latour and Woolgar’s study regarding various motivations for publishing. The study found that there are some similarities between the two investigated disciplines, especially in the context of extra-disciplinary factors that have impact on scholars’ publishing choices. The study also revealed that the general awareness of open access is rather good among the participating academics, however the number of open access publications is not very high. In addition, the findings suggest that there were some misunderstanding about the definitions and functions of institutional repositories among scholars. / Program: Masterprogram: Biblioteks- och informationsvetenskap, Digitala bibliotek och informationstjänster
64

Estudo da migração de radionuclídeos em depósito para fontes seladas tipo poço tubular / Study of radionuclide migration in repository type tubular well for sealed sources deposition

Sabbag, Maurício Guimarães 15 April 2013 (has links)
Visando contribuir com o desenvolvimento de uma metodologia adequada ao Brasil para deposição de fontes seladas fora de uso, o presente estudo avaliou cenários de migração de radionuclídeos para fora de um repositório profundo tipo poço tubular. Considerou-se uma fratura anelar como caminho preferencial de fluxo da água subterrânea, que futuramente adentrará os poços, entrando em contato direto com as fontes. No futuro, fenômenos naturais e ação antrópica poderiam levar à degradação dos materiais que formam as barreiras artificiais do repositório e formar uma via preferencial de transporte e migração dos radioisótopos depositados. Haveria intrusão de água subterrânea e contato com as fontes seladas, corrosão e transporte dos radioisótopos para o ambiente acessível ao homem. A modelagem de transporte considerou percolação de água subterrânea numa fratura causada pelo descolamento entre o tubo de aço e a pasta de cimento, que separa o repositório do meio geológico. Foram simulados cenários de migração e o estudo poderá ser aproveitado na escolha de sítio e de novas técnicas para selagem. Diferentes gradientes hidráulicos e espessuras de fratura, entre outros parâmetros, influirão diretamente no fluxo pela fratura postulada que resultarão em diferentes tempos de trânsito até a biosfera. / The present study models radionuclide migration scenarios out of a deep borehole for disposal of disused sealed radioactive sources (DSRS). The aim is to contribute to the development of methodologies for the safety assessment of the repository. It is assumed that, in the future, anthropogenic and natural phenomena could impair the capacity of the engineered barriers to prevent the radionuclides from spreading to the accessible environment. Groundwater intrudes into the repository, corrodes the sealed sources and transports the radioisotopes to the biosphere. The model considers percolation of groundwater through an annular fracture caused by a detachment between the borehole steel casing and the cement backfill. A range of values of hydraulic gradients, fracture apertures, radionuclide sorption capacity in the cement backfill were considered in calculating flow and radionuclide transport through the postulated fracture. The present study shows, by comparing different scenarios, the variation of hydraulic gradients associated with different apertures of the fracture, exposing, through charts, the radionuclides transit times. The results of the study may be used in safety assessments and for selecting sites and materials for a 400 m deep borehole repository, for the present Brazilian inventory of DSRS.
65

Facilitating data sharing : a design approach to incorporate context into the research data repository

Garza Gutierrez, Kristian January 2017 (has links)
We asked whether the design of a Science Data Repository (SDR) can influence data sharing behaviour in small scientific collaborations. We hypothesised that an SDR can influence data-sharing behaviour when its design considers the context of data-sharing. We proposed an alternative approach to those documented in the literature, employing a combination of socio-technical empirical and analytical methods for context capturing, and choice architecture for context incorporation. To evaluate the approach we applied it to design features in a Scientific Data Repository for a population of small scientific collaborations within the Life Sciences. The application of this thesis' approach consisted of an exploratory case study, a review of factors associated with data sharing, the definition of design claims, and implementation of a set of design features. We collected data using interviews with members of the collaborations and designers of the SDR; as well as obtaining the data-logs from the collaborations' SDR. We evaluated the resulting design features using an asynchronous web experiment. We found that using the empirical approach to context capturing we are able to effectively identify factors associated with data sharing in the small scientific collaborations. Moreover, we identified a number of limitations on the application of the analytical approach to context capturing. Furthermore, we found that the Choice Architecture based procedure for context incorporation can define effective design features in Science Data Repositories. In this work, we show that we can facilitate data-sharing by incorporating context into the design of a Science Data Repository, and identified a set of restrictions to use our approach. The approach proposed in this thesis can be used by practitioners wishing to improve data sharing in an SDR. Contributions, such as the survey of factors associated with data sharing behaviour, can be used by researchers to understand the problems associated with data sharing in small scientific collaborations.
66

Estudo da migração de radionuclídeos em depósito para fontes seladas tipo poço tubular / Study of radionuclide migration in repository type tubular well for sealed sources deposition

Maurício Guimarães Sabbag 15 April 2013 (has links)
Visando contribuir com o desenvolvimento de uma metodologia adequada ao Brasil para deposição de fontes seladas fora de uso, o presente estudo avaliou cenários de migração de radionuclídeos para fora de um repositório profundo tipo poço tubular. Considerou-se uma fratura anelar como caminho preferencial de fluxo da água subterrânea, que futuramente adentrará os poços, entrando em contato direto com as fontes. No futuro, fenômenos naturais e ação antrópica poderiam levar à degradação dos materiais que formam as barreiras artificiais do repositório e formar uma via preferencial de transporte e migração dos radioisótopos depositados. Haveria intrusão de água subterrânea e contato com as fontes seladas, corrosão e transporte dos radioisótopos para o ambiente acessível ao homem. A modelagem de transporte considerou percolação de água subterrânea numa fratura causada pelo descolamento entre o tubo de aço e a pasta de cimento, que separa o repositório do meio geológico. Foram simulados cenários de migração e o estudo poderá ser aproveitado na escolha de sítio e de novas técnicas para selagem. Diferentes gradientes hidráulicos e espessuras de fratura, entre outros parâmetros, influirão diretamente no fluxo pela fratura postulada que resultarão em diferentes tempos de trânsito até a biosfera. / The present study models radionuclide migration scenarios out of a deep borehole for disposal of disused sealed radioactive sources (DSRS). The aim is to contribute to the development of methodologies for the safety assessment of the repository. It is assumed that, in the future, anthropogenic and natural phenomena could impair the capacity of the engineered barriers to prevent the radionuclides from spreading to the accessible environment. Groundwater intrudes into the repository, corrodes the sealed sources and transports the radioisotopes to the biosphere. The model considers percolation of groundwater through an annular fracture caused by a detachment between the borehole steel casing and the cement backfill. A range of values of hydraulic gradients, fracture apertures, radionuclide sorption capacity in the cement backfill were considered in calculating flow and radionuclide transport through the postulated fracture. The present study shows, by comparing different scenarios, the variation of hydraulic gradients associated with different apertures of the fracture, exposing, through charts, the radionuclides transit times. The results of the study may be used in safety assessments and for selecting sites and materials for a 400 m deep borehole repository, for the present Brazilian inventory of DSRS.
67

Avaliação da alteração das propriedades da pasta de cimento em ambiente de repositório / Assessment of cement paste properties changes in repository environment

Eduardo Gurzoni Alvares Ferreira 30 April 2013 (has links)
Pasta de cimento é um material comum em repositórios para rejeitos radioativos, atuando como material estrutural e de imobilização. Sua utilização como material de preenchimento em um repositório tipo poço tubular profundo para fontes seladas, no entanto, requer um maior tempo de vida útil do material. O conhecimento de seu comportamento em longo prazo é necessário para garantir a segurança da instalação em milhares de anos. O presente trabalho avaliou as alterações na pasta de cimento induzidas por fatores de degradação, como ataque de agentes agressivos, alta temperatura e presença de campo de radiação. Corpos de prova (cps) de pasta de cimento foram submetidos a ensaios acelerados de degradação e os efeitos deletérios foram avaliados por meio de ensaios de resistência mecânica, variação dimensional, lixiviação/penetração de íons, DRX, TGA e MEV. Observou-se que a hidratação dos cps foi beneficiada pela imersão (em água destilada ou em solução salina) e alta temperatura, resultando em uma resistência maior. O armazenamento à seco prejudicou a hidratação, mantendo a resistência mais baixa. O tempo de imersão e a irradiação não foram capazes de alterar a mineralogia e a resistência da pasta de cimento. / Cement paste is widely used in repositories for radioactive wastes, acting as structural and immobilization material. However, its use as backfill material in boreholes for sealed sources requires a longer service life of this material. The assessment of the cement paste behavior in long term is needed to improve the confidence that the material will perform as required during the service life of the facility. This research evaluated the changes in cement paste induced by degradation parameters. Portland cement paste specimens (cps) were submitted to accelerated degradation tests and the damage effects was evaluated by mechanical strength, variation of sample mass and volume, leaching/penetration of ions, XRD, TGA and SEM. It was observed that cps hydration was benefited by immersion (in distilled water or salt solution) and high temperatures, resulting in a higher strength. Dry storage, however, influenced the hydration process and maintained strength lower. Time of treatment and irradiation were not able to alter mineralogy and durability of cement paste.
68

Representação do componente de software na FARCSoft: ferramenta de apoio à reutilização de componentes de software. / Software component representation in the FARCSoft: software component reuse suport tool.

Ana Claudia Rossi 16 April 2004 (has links)
Atualmente, as organizações estão cada vez mais dependentes de sistemas de informação para a realização de seus negócios. Com isso, uma das preocupações, na área de desenvolvimento de software, é a obtenção cada vez mais rápida de sistemas que atendam as necessidades atuais e que sejam flexíveis para acompanhar as mudanças de tecnologia e práticas de negócio. A reutilização de componentes de software tem sido considerada uma das formas para obter redução dos custos e do tempo de desenvolvimento e aumento da produtividade e da qualidade do produto de software. A implantação da reutilização de componentes é baseada em três elementos principais que consistem de um processo de desenvolvimento voltado para reutilização, de uma ferramenta adequada e de uma cultura de projeto. A ferramenta, por sua vez, deve ter a capacidade de armazenar os componentes e de fornecer recursos para uma recuperação eficiente. O objetivo deste trabalho é definir uma representação de componentes em um repositório, a qual permita armazenar diferentes tipos de componentes de software. Para isso, foi especificada a Ferramenta de Apoio à Reutilização de Componentes de Software, denominada de – FARCSoft, que deve fornecer suporte à reutilização de componentes de software. Esta ferramenta apresenta recursos para armazenar, gerenciar, buscar e recuperar os componentes do seu repositório. A capacidade de representação foi avaliada por meio de um conjunto de componentes de tipos, porte e tecnologia diversos, os quais foram modelados e catalogados. / Nowadays, organizations increasingly depend on information systems to carry out their business. Thus, one of the preoccupations in the software development area is the need to obtain systems faster and faster, attending to current needs and sufficiently flexible to accompany changes in technology and business practices. Software component reuse has been considered one of the ways to reduce costs and development time and increase productivity and software quality. The implantation of component reuse is based on three main elements, which consist in a development process oriented towards reuse, an adequate tool and a project culture. The tool, in turn, must be able to store the components and to supply resources for the sake of efficient recovery. This study aims to define a component representation in a repository, which allows for the storage of different kinds of software components. For this purpose, a Software Component Reuse Support Tool was specified, called FARCSoft, which should support the reuse of software components. This tool presents resources to store, manage, search and recover the components of a repository. Representation capacity was evaluated by means of a set of components with different types, sizes and technologies, which were modeled and catalogued.
69

We've Got A Guide for That: Building a Comprehensive Marketing and Support Framework for IR Services

Mortimore, Jeffrey M. 01 June 2018 (has links)
Institutional Repository services require continuous, multi-channel promotion and support to attract and retain conferences, journals, and other campus collections. However, given the relative complexity of the services offered, balancing promotional messaging with a clear representation of repository offerings, policies, and procedures can be a challenge. Providing a flexible but robust marketing and support framework is especially important for institutions that rely on non-repository public services personnel to provide front-line promotion of repository services to faculty and administrators. During this session, we will look at Georgia Southern University's recently-developed Institutional Repository Services LibGuide as a model for providing such a framework (http://georgiasouthern.libguides.com/irservices/overview). This portal simultaneously provides 1) a front-line promotional tool, 2) a client-management tool for setup and support consultations, and 3) a storehouse for repository-related documents, forms, MOUs, and licenses. This portal further integrates with the library's other scholarly communications-related guides, providing seamless representation of these services to patrons. Participants will use this guide as a jumping-off point to discuss strategies and best practices for mediating institutional repository services, and for integrating repository promotion and support into libraries' broader scholarly communications initiatives.
70

High-Resolution Seismics Methods Applied to Till Covered Hard Rock Environments

Bergman, Björn January 2005 (has links)
<p>Reflection seismic and seismic tomography methods can be used to image the upper kilometer of hard bedrock and the loose unconsolidated sediments covering it. Developments of these two methods and their application, as well as identifying issues concerning their usage, are the main focus of the thesis. Data used for this development were acquired at three different sites in Sweden, in Forsmark 140 km north of Stockholm, in the Oskarshamn area in southern Sweden, and in the northern part of the Siljan Ring impact crater area.</p><p>The reflection seismic data were acquired with long source-receiver offsets relative to some of the targeted depths to be imaged. In the initial processing standard steps were applied, but the uppermost part of the sections were not always clear. The longer offsets imply that pre-stack migration is necessary in order to image the uppermost bedrock as clearly as possible. Careful choice of filters and velocity functions improve the pre-stack migrated image, allowing better correlation with near-surface geological information.</p><p>The seismic tomography method has been enhanced to calculate, simultaneously with the velocity inversion, optimal corrections to the picked first break travel times in order to compensate for the delays due to the seismic waves passing through the loose sediments covering the bedrock.</p><p>The reflection seismic processing used in this thesis has produced high-quality images of the upper kilometers, and in one example from the Forsmark site, the image of the uppermost 250 meters of the bedrock has been improved. The three-dimensional orientation of reflections has been determined at the Oskarshamn site. Correlation with borehole data shows that many of these reflections originate from fracture zones. </p><p>The developed seismic tomography method produces high-detail velocity models for the site in the Siljan impact area and for the Forsmark site. In Forsmark, detailed estimates of the bedrock topography were calculated with the use of the developed tomography method.</p>

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