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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

Interprétation de mesures de déformation en forage en terrain anisotrope : retour d’expérience de l’utilisation de cellules CSIRO dans l’argilite de Tournemire (Aveyron) / Interpretation of the hole's strain measurements in anisotropic field : feedback from the use of CSIRO cells in the Tournemire argillite (Aveyron)

Ben Ouanas, Abdelmonem 26 November 2010 (has links)
En géomécanique, la caractérisation de l’état de contrainte et de la rhéologie d’un massif rocheux peut être obtenue en mesurant la réponse en déformation du terrain sous l’effet d’une sollicitation connue. Une méthode parmi d’autres consiste à recourir pour cela à une cellule de mesure intégrée (comportant des capteurs de déformation orientés selon différentes directions) installée dans un forage et rendue solidaire du massif par l’intermédiaire d’une colle époxy. Ce principe de mesure est utilisé, notamment, pour déterminer l’état de contraintes in situ par la méthode dite de « surcarottage » et les caractéristiques élastiques de la roche à partir de l’essai « biaxial ».Entre novembre 2005 et janvier 2006, une campagne d’essais géomécaniques de ce type a été menée dans l’argilite de Tournemire (Aveyron, France), à l’aide des cellules CSIRO. Les mesures de déformation obtenues ont révélé des phénomènes inhabituels qui ont rendu délicate la détermination des caractéristiques élastiques anisotropes de la roche et impossible l’accès aux contraintes du site.La présente thèse a pour objectif de contribuer, par la recherche d’explications à l’origine de ces phénomènes, d’une part, à l’amélioration de la connaissance du comportement de l’argilite de Tournemire et, d’autre part, à l’amélioration du protocole de mesure et d’interprétation de déformations obtenues par cellules CSIRO.Notre démarche consiste, dans un premier temps, à émettre un certain nombre d’hypothèses explicatives des phénomènes observés par la recherche bibliographique. Dans un deuxième temps, nous testons ces hypothèses à travers la modélisation analytique et numérique des essais de surcarottage et biaxiaux, puis à travers la réalisation de nouvelles expérimentations in situ et en laboratoire sur l’argilite, mais aussi sur des matériaux-tests (ciment, échantillon de colle).Nous concluons que les phénomènes inhabituels observés résultent, pour l’essentiel, des conditions de mise en œuvre in situ des cellules CSIRO. En particulier, nous mettons l’accent sur les artéfacts induits par le comportement visco-plastique de la colle époxy lorsqu’elle n’est pas parfaitement polymérisée. Le rôle de l’endommagement de la roche généré par les opérations de forage est également discuté. Nous en tirons des recommandations pratiques pour la réalisation de nouveaux essais dans des conditions similaires / In Geomechanics, determining the state of stress and the rheology of rock massive can be obtained by measuring the strain response of the ground under the effect of a known stress. A method among others is to use a cell integrated (with strain gauges oriented in different directions) installed in a borehole and secured to the mass through an epoxy glue. This measurement is used, notably, to determine the stress state in situ by the « overcoring » method and the elastic parameters of the rock from the « biaxial » test.Between November 2005 and January 2006, a geomechanical testing campaign was conducted in the argillaceous formation of the Tournemire experimental site (Aveyron, France) using CSIRO Hi cells. The strain measurements obtained during overcoring and biaxial tests, have shown unusual phenomena, which have made difficult the determination of anisotropic elastic parameters of the rock and the access to the site stress.Therefore, through researches for explanations of the origin of these phenomena, this thesis aims to improve and to contribute to the understanding of argillite Tournemire’s behaviour and to upgrade the measurement protocol as well as the interpretation of cells CSIRO’s strain.Our approach is, firstly, to issue a number of hypotheses to explain certain, phenomena observed in literature. In a second step, we test these hypotheses through analytical and numerical modelling of the biaxial and overcoring tests then through the realization of new experiments in situ within laboratory on argillite, and also on materials tests (cement, sample of glue).We conclude that the unusual phenomena observed are essentially the result of the conditions for implementing in situ CSIRO’s cell. In particular, we focus on the artefacts induced by the visco-plastic behaviour of the epoxy glue when it is incompletely polymerised. The role of damage on the rock generated by drilling operations is also discussed. We draw some practical recommendations for implementing new tests under similar conditions
62

Adhesive Wafer Bonding for Microelectronic and Microelectromechanical Systems

Frank, Niklaus January 2002 (has links)
<p>Semiconductor wafer bonding has been a subject of interestfor many years and a wide variety of wafer bonding techniqueshave been reported in literature. In adhesive wafer bondingorganic and inorganic adhesives are used as intermediatebonding material. The main advantages of adhesive wafer bondingare the relatively low bonding temperatures, the lack of needfor an electric voltage or current, the compatibility withstandard CMOS wafers and the ability to join practically anykind of wafer materials. Adhesive wafer bonding requires nospecial wafer surface treatmentssuch as planarisation.Structures and particles at the wafer surfaces can be toleratedand compensated for some extent by the adhesive material.Adhesive wafer bonding is a comparably simple, robust andlowcost bonding process. In this thesis, adhesive wafer bondingtechniques with different polymer adhesives have beendeveloped. The relevant bonding parameters needed to achievehigh quality and high yield wafer bonds have been investigated.A selective adhesive wafer bonding process has also beendeveloped that allows localised bonding on lithographicallydefined wafer areas.</p><p>Adhesive wafer bonding has been utilised in variousapplication areas. A novel CMOS compatible film, device andmembrane transfer bonding technique has been developed. Thistechnique allows the integration of standard CMOS circuits withthin film transducers that can consist of practically any typeof crystalline or noncrystalline high performance material(e.g. monocrystalline silicon, gallium arsenide,indium-phosphide, etc.). The transferred transducers or filmscan be thinner than 0.3 µm. The feature sizes of thetransferred transducers can be below 1.5 µm and theelectrical via contacts between the transducers and the newsubstrate wafer can be as small as 3x3 µm2. Teststructures for temperature coefficient of resistancemeasurements of semiconductor materials have been fabricatedusing device transfer bonding. Arrays of polycrystallinesilicon bolometers for use in uncooled infrared focal planearrays have been fabricated using membrane transfer bonding.The bolometers consist of free-hanging membrane structures thatare thermally isolated from the substrate wafer. Thepolycrystalline silicon bolometers are fabricated on asacrificial substrate wafer. Subsequently, they are transferredand integrated on a new substrate wafer using membrane transferbonding. With the same membrane transfer bonding technique,arrays of torsional monocrystalline silicon micromirrors havebeen fabricated. The mirrors have a size of 16x16 µm2 anda thickness of 0.34 µm. The advantages of micromirrorsmade of monocrystalline silicon are their flatness, uniformityand mechanical stability. Selective adhesive wafer bonding hasbeen used to fabricate very shallow cavities that can beutilised in packaging and component protection applications. Anew concept is proposed that allows hermetic sealing ofcavities fabricated using adhesive wafer bonding. Furthermore,microfluidic devices, channels and passive valves for use inmicro total analysis systems are presented.</p><p>Adhesive wafer bonding is a generic CMOS compatible bondingtechnique that can be used for fabrication and integration ofvarious microsystems such as infrared focal plane arrays,spatial light modulators, microoptical systems, laser systems,MEMS, RF-MEMS and stacking of active electronic films forthree-dimensional high-density integration of electroniccircuits. Adhesive wafer bonding can also be used forfabrication of microcavities in packaging applications, forwafer-level stacking of integrated circuit chips (e.g. memorychips) and for fabrication of microfluidic systems.</p>
63

Hydrological and sediment Yield modelling in Lake Tana Basin, Blue Nile Ethiopia

Setegn, Shimelis Gebriye January 2008 (has links)
<p>Land and water resources degradation are the major problems on the Ethiopian highlands. Poor land use practices and improper management systems have played a significant role in causing high soil erosion rates, sediment transport and loss of agricultural nutrients. So far limited meas-ures have been taken to combat the problems. In this study a physically based watershed model, SWAT2005 was applied to the Northern Highlands of Ethiopia for modelling of the hydrology and sediment yield. The main objective of this study was to test the performance and feasibility of SWAT2005 model to examine the influence of topography, land use, soil and climatic condi-tion on streamflows, soil erosion and sediment yield. The model was calibrated and validated on four tributaries of Lake Tana as well as Anjeni watershed using SUFI-2, GLUE and ParaSol algo-rithms. SWAT and GIS based decision support system (MCE analysis) were also used to identify the most erosion prone areas in the Lake Tana Basin. Streamflows are more sensitive to the hy-drological response unites definition thresholds than subbasin discretization. Prediction of sedi-ment yield is highly sensitive to subbasin size and slope discretization. Baseflow is an important component of the total discharge within the study area that contributes more than the surface runoff. There is a good agreement between the measured and simulated flows and sediment yields with higher values of coefficients of determination and Nash Sutcliffe efficiency. The an-nual average measured sediment yield in Anjeni watershed was 24.6 tonnes/ha. The annual aver-age simulated sediment yield was 27.8 and 29.5 tonnes/ha for calibration and validation periods, respectively. The SWAT model indicated that 18.5 % of the Lake Tana Basin is erosion potential areas. Whereas the MCE result indicated that 25.5 % of the basin are erosion potential areas. The calibrated model can be used for further analysis of the effect of climate and land use change as well as other different management scenarios on streamflows and soil erosion. The result of the study could help different stakeholders to plan and implement appropriate soil and water conser-vation strategies.</p>
64

Analyse d'images satellitaires d'inondations pour la caractérisation tridimensionnelle de l'aléa et l'aide à la modélisation hydraulique

Hostache, Renaud 12 1900 (has links) (PDF)
Ce travail vise à étendre les méthodes d'analyse d'images satellitaires de crues au-delà de la détection des limites d'inondation afin d'estimer des niveaux d'eau distribués dans l'espace et d'aider la modélisation hydraulique.Inspirée des travaux de Raclot (2003) sur photographies aériennes qui fournissent des incertitudes moyennes de ±20cm, la méthode d'estimation des niveaux d'eau utilise des images satellitaires RADAR de crue et un MNT fin. Elle repose sur 1) une phase de télédétection pour cartographier l'inondation et analyser la pertinence de ses limites pour l'estimation des niveaux d'eau, 2) une phase d'analyse spatiale dans laquelle les niveaux d'eau sont estimés par croisement entre les limites pertinentes et un MNT fin, puis contraints par le schéma de circulation des eaux. Les estimations de niveaux d'eau obtenues ont une incertitude moyenne de ±38cm pour une image RADARSAT-1 d'une crue de la Moselle (France, 1997). Des travaux de validation ont permis de calculer une RMSE de l'ordre de 13cm pour une image ENVISAT de l'Alzette (Luxembourg, 2003).Pour aider la modélisation hydraulique, la démarche proposée vise à réduire le phénomène d'équifinalité grâce aux images satellitaires. Pour cela, un calage "traditionnel" à partir d'hydrogrammes observés est complété par la comparaison entre résultats du modèle et surfaces inondées ou niveaux d'eau extraits des images. Pour cerner les incertitudes du calage, des simulations Monte-Carlo ont été mises en place. En perspective, la prévision de l'évolution d'une crue après acquisition d'une image devrait bénéficier de modèles mieux contraints grâce à l'utilisation des images comme condition initiale ou donnée de calage.
65

Adhesive Wafer Bonding for Microelectronic and Microelectromechanical Systems

Frank, Niklaus January 2002 (has links)
Semiconductor wafer bonding has been a subject of interestfor many years and a wide variety of wafer bonding techniqueshave been reported in literature. In adhesive wafer bondingorganic and inorganic adhesives are used as intermediatebonding material. The main advantages of adhesive wafer bondingare the relatively low bonding temperatures, the lack of needfor an electric voltage or current, the compatibility withstandard CMOS wafers and the ability to join practically anykind of wafer materials. Adhesive wafer bonding requires nospecial wafer surface treatmentssuch as planarisation.Structures and particles at the wafer surfaces can be toleratedand compensated for some extent by the adhesive material.Adhesive wafer bonding is a comparably simple, robust andlowcost bonding process. In this thesis, adhesive wafer bondingtechniques with different polymer adhesives have beendeveloped. The relevant bonding parameters needed to achievehigh quality and high yield wafer bonds have been investigated.A selective adhesive wafer bonding process has also beendeveloped that allows localised bonding on lithographicallydefined wafer areas. Adhesive wafer bonding has been utilised in variousapplication areas. A novel CMOS compatible film, device andmembrane transfer bonding technique has been developed. Thistechnique allows the integration of standard CMOS circuits withthin film transducers that can consist of practically any typeof crystalline or noncrystalline high performance material(e.g. monocrystalline silicon, gallium arsenide,indium-phosphide, etc.). The transferred transducers or filmscan be thinner than 0.3 µm. The feature sizes of thetransferred transducers can be below 1.5 µm and theelectrical via contacts between the transducers and the newsubstrate wafer can be as small as 3x3 µm2. Teststructures for temperature coefficient of resistancemeasurements of semiconductor materials have been fabricatedusing device transfer bonding. Arrays of polycrystallinesilicon bolometers for use in uncooled infrared focal planearrays have been fabricated using membrane transfer bonding.The bolometers consist of free-hanging membrane structures thatare thermally isolated from the substrate wafer. Thepolycrystalline silicon bolometers are fabricated on asacrificial substrate wafer. Subsequently, they are transferredand integrated on a new substrate wafer using membrane transferbonding. With the same membrane transfer bonding technique,arrays of torsional monocrystalline silicon micromirrors havebeen fabricated. The mirrors have a size of 16x16 µm2 anda thickness of 0.34 µm. The advantages of micromirrorsmade of monocrystalline silicon are their flatness, uniformityand mechanical stability. Selective adhesive wafer bonding hasbeen used to fabricate very shallow cavities that can beutilised in packaging and component protection applications. Anew concept is proposed that allows hermetic sealing ofcavities fabricated using adhesive wafer bonding. Furthermore,microfluidic devices, channels and passive valves for use inmicro total analysis systems are presented. Adhesive wafer bonding is a generic CMOS compatible bondingtechnique that can be used for fabrication and integration ofvarious microsystems such as infrared focal plane arrays,spatial light modulators, microoptical systems, laser systems,MEMS, RF-MEMS and stacking of active electronic films forthree-dimensional high-density integration of electroniccircuits. Adhesive wafer bonding can also be used forfabrication of microcavities in packaging applications, forwafer-level stacking of integrated circuit chips (e.g. memorychips) and for fabrication of microfluidic systems.
66

Estudo do fator de forma de área em reparo com chapa colada em tubulações com furo / Study of form factor of repair in area with plate stuckin pipes with hole

Ricardo Hudson da Silva 09 February 2015 (has links)
Este trabalho tem por finalidade o estudo da resistência à pressão hidrostática do reparo realizado com chapa de aço de baixo carbono, colada com adesivo estrutural à base de epóxi em tubulações de aço com furo. Tubulações de parede fina, sob pressão interna, a tensão na direção longitudinal é a metade da tensão circunferencial do tubo, deste modo, o fator de forma da área do reparo, ou seja, a variação das dimensões da chapa nas direções longitudinal e circunferencial do tubo foi investigado. A influência da força de falha do reparo, quando varia-se a dimensão da chapa nas direções citadas, foram analisadas estatisticamente utilizando-se um planejamento fatorial de experimentos. Altos valores de resistência hidrostática do reparo foram encontrados (em torno de 240 bar) quando comparados com as pressões normais de trabalho (em torno de 70 bar) de uma tubulação similar as utilizadas nos testes. Os resultados da pressão de falha do reparo dos 10 grupos analisados apresentaram desvios padrão pequenos, menor que 12 %, demonstrando a eficiência dos procedimentos adotados na confecção do reparo. Os estudos demonstram a não existência de um fator de forma na resistência do reparo devido a variação nas dimensões da chapa nas direções longitudinal e circunferencial do tubo bem como a alta influência na resistência do reparo quando aumenta a área da chapa. Os resultados apontam para o desenvolvimento de um novo procedimento de reparo de contingência. / In this work, the resistance to hydrostatic pressure of repair with steel plate low carbon, glued with structural adhesive epoxy in the steel pipes with hole was investigated. Thin-wall pipes under internal pressure, the tension in the longitudinal direction is half the circumferential stress the pipe, thus the shape factor of repair area, that is, the change of the plate size in the longitudinal and circumferential directions tube was evaluated. The influence of repair failure strength when vary the size of the plate in the mentioned directions, were statistically analyzed using a factorial experiments desing. High values of the hydrostatic resistance in the repair were found (around 240 bar) compared with the normal working pressure (around 70 bar) in a similar pipe used in the tests. The results of repair failure pressure of the 10 groups analyzed small standard deviations, less than 12%, demonstrating the efficiency of the procedures adopted in the bonding mechanism. The study demonstrated of any existence of the form factor in the repair resistance due to variation in the dimensions of the plate in the longitudinal and circumferential direction, even as the high influence in the repair resistance with the increase from the area plate. The results point to the development of a new contingency repair procedure.
67

Estudo do fator de forma de área em reparo com chapa colada em tubulações com furo / Study of form factor of repair in area with plate stuckin pipes with hole

Ricardo Hudson da Silva 09 February 2015 (has links)
Este trabalho tem por finalidade o estudo da resistência à pressão hidrostática do reparo realizado com chapa de aço de baixo carbono, colada com adesivo estrutural à base de epóxi em tubulações de aço com furo. Tubulações de parede fina, sob pressão interna, a tensão na direção longitudinal é a metade da tensão circunferencial do tubo, deste modo, o fator de forma da área do reparo, ou seja, a variação das dimensões da chapa nas direções longitudinal e circunferencial do tubo foi investigado. A influência da força de falha do reparo, quando varia-se a dimensão da chapa nas direções citadas, foram analisadas estatisticamente utilizando-se um planejamento fatorial de experimentos. Altos valores de resistência hidrostática do reparo foram encontrados (em torno de 240 bar) quando comparados com as pressões normais de trabalho (em torno de 70 bar) de uma tubulação similar as utilizadas nos testes. Os resultados da pressão de falha do reparo dos 10 grupos analisados apresentaram desvios padrão pequenos, menor que 12 %, demonstrando a eficiência dos procedimentos adotados na confecção do reparo. Os estudos demonstram a não existência de um fator de forma na resistência do reparo devido a variação nas dimensões da chapa nas direções longitudinal e circunferencial do tubo bem como a alta influência na resistência do reparo quando aumenta a área da chapa. Os resultados apontam para o desenvolvimento de um novo procedimento de reparo de contingência. / In this work, the resistance to hydrostatic pressure of repair with steel plate low carbon, glued with structural adhesive epoxy in the steel pipes with hole was investigated. Thin-wall pipes under internal pressure, the tension in the longitudinal direction is half the circumferential stress the pipe, thus the shape factor of repair area, that is, the change of the plate size in the longitudinal and circumferential directions tube was evaluated. The influence of repair failure strength when vary the size of the plate in the mentioned directions, were statistically analyzed using a factorial experiments desing. High values of the hydrostatic resistance in the repair were found (around 240 bar) compared with the normal working pressure (around 70 bar) in a similar pipe used in the tests. The results of repair failure pressure of the 10 groups analyzed small standard deviations, less than 12%, demonstrating the efficiency of the procedures adopted in the bonding mechanism. The study demonstrated of any existence of the form factor in the repair resistance due to variation in the dimensions of the plate in the longitudinal and circumferential direction, even as the high influence in the repair resistance with the increase from the area plate. The results point to the development of a new contingency repair procedure.
68

Jezdecká hala ve Valašském Meziříčí / The Riding Hall in Valašské Meziříčí

Rantová, Katarína January 2018 (has links)
The subject matter of this diploma thesis is a design timber structure of riding hall. The hall is a one nave building. The dimensions of ground plans is 32,0m x 70,0m and the hall is 10,0 meters high. The load-bearing structure consists of arched ribs.This timber structure composed of glued laminated timber. The building is located in Valašské Meziříčí, climate loads are designed for the area. The calculation were made in accordance with the Czech technical norms ČSN EN. The structural design and analysis is performed by software SCIA Engineer 17.
69

Automatický aplikační systém ochranných rohů paletizovaného materiálu / Automatic application system of protecting corners of palletized materials

Havelka, Michal January 2021 (has links)
The diploma thesis is about the design of an automatic application system of edge protection corners to palletized material. As the first the diploma thesis briefly discusses actual principles and solutions in area of palletization. After that, there are 4 potential solutions described and measured by multicriteria evaluation method where the most suitable solution is being chosen. Then the actual act of designing of the chosen solution is described and also there are solved necessary calculations. In the end there is risk analysis of new workplace and the drawing documentation of selected nodes is attached. The diploma thesis’ assignment has been made in cooperation with company PHATEC s.r.o. in Litomyšl.
70

Aquapark / Aquapark

Vincour, Jan January 2014 (has links)
Object of Diploma thesis is the structural design of a load bearing structure of the aquapark in the Brno area. The main structure is designed as lamella arch on the cylindrical surface with one curvature with 30 m span and 4.5 m camber. The structural material is glue-laminated timber with inner steel plate joints.

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