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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.
231

Elementos contributivos para redução da repetência: o caso do CIEP Brizolão 386

Mello, Elizabeth Ribeiro 24 July 2013 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-03-30T17:26:45Z No. of bitstreams: 1 elizabethribeiromello.pdf: 964968 bytes, checksum: cd37c296b8d64d60eab894c3169b3ff1 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-04-24T02:55:00Z (GMT) No. of bitstreams: 1 elizabethribeiromello.pdf: 964968 bytes, checksum: cd37c296b8d64d60eab894c3169b3ff1 (MD5) / Made available in DSpace on 2016-04-24T02:55:01Z (GMT). No. of bitstreams: 1 elizabethribeiromello.pdf: 964968 bytes, checksum: cd37c296b8d64d60eab894c3169b3ff1 (MD5) Previous issue date: 2013-07-24 / O tema proposto neste trabalho tem como alvo a presença de elevados índices de reprovação no CIEP 386. O objetivo é conhecer os principais problemas enfrentados pelo CIEP 386 que justifiquem suas elevadas taxas de reprovação e, então, propor ações que possibilitem diminuí-las. Para tal utiliza-se o questionário contextual aplicado aos alunos do 3ª serie do Ensino Médio, quando da realização das provas do SAERJ (Sistema de Avaliação do Estado do Rio deJaneiro) de 2011 e dados administrativos, obtidos diretamente da secretaria da escola. Baseados nos resultados obtidos e na gestão escolar desenvolvida nesta unidade, traça-se um plano de ação educacional constituído por: reforço escolar para Português com o Projeto de Leitura e Produção Textual utilizando a tecnologia, nivelamento curricular e reforço escolar para o ensino de Matemática com jogos matemáticos, aulas práticas para Área de Ciências e suas Tecnologias, criação de um modelo de recuperação paralela, monitoramento dos resultados das avaliações externas e internas, promoção de uma campanha de valorização do espaço escolar visando um maior estímulo ao processo de aprendizagem, atingindo diretamente as principais partes envolvidas: professor e aluno.Todas as ações visam diminuir os índices de reprovação e, consequentemente, elevar a qualidade do ensino. / High rates of failure are a kind of the most problems that high school in Rio de Janeiro has been frequently faced. An important line of study now a days in education is to understand why these this rates are so high. The point of the view of this work is these results and after than the work is to propose actions that can do this rates go down. This project is made in CIEP 386. For this study the work uses the contextual questionnaire applied to students of 3rd grade of high school, when carrying out the tests in SAERJ (Evaluation System of the State of Rio de Janeiro), 2011 and administrative data obtained directly from the school office. Based on these results and the school management developed in this unit, the plan is to draw up an action plan educational that have: tutoring for Portuguese with Project Reading and Textual Production using technology, leveling curricular and school for teaching mathematics with mathematical games, classes for area Science and its technologies, creating a model of parallel recovery, monitoring the results of the external and internal evaluations, promoting a campaign appreciation of the school designed to further stimulate the learning process, directly affecting key stakeholders: teachers and students. All of this actions were choosing to raise the quality of education.
232

Verstärkung von Stahlbetonstützen mit Kreisquerschnitt durch Umschnürung mit CFK-Werkstoffen

Käseberg, Stefan 16 January 2017 (has links) (PDF)
Die vorliegende Arbeit beschäftigt sich mit der Umschnürung von gedrungenen Stahlbetonstützen mittels Kohlefasergelegen. Die durch Epoxidharz mit dem Altbeton verbundenen Kohlefasern (CFK-Umschnürung) bewirken hierbei eine starke Behinderung der Querdehnung des Betons, wodurch dieser in einen dreidimensionalen Spannungszustand versetzt wird. Die Betondruckfestigkeit kann dadurch nachträglich deutlich gesteigert und das Verformungsverhalten positiv beeinflusst werden. Forschungsaufgabe war es, Wissenslücken und aufgeworfene Fragen, die sich aus einer intensiven Literaturrecherche zur Thematik ergaben, zu schließen und einen eigenen Bemessungsansatz zu entwickeln. Hierzu wurden Beton- und Stahlbetondruckglieder mit verschiedenen Abmessungen und Durchmessern sowie unterschiedlichen Längs- und Querbewehrungsgehalten hergestellt. Danach erfolgte die Umschnürung dieser Prüfkörper mit verschiedenen CFK-Materialien in variierenden Dicken und anschließende Bauteiltests in Form von weggesteuerten Druckversuchen. Neben dem Materialverhalten konnten mittels elektrischen Messsystemen, wie z. B. induktiven Wegaufnehmern sowie auf den Prüfkörpern aufgebrachten Dehnungsmessstreifen, auch die Versagenszustände zuverlässig bestimmt werden. Die Auswertung und Interpretation der gewonnenen Daten mündete in empirischen Gleichungen zur Beschreibung der maximalen Druckfestigkeit und Dehnung von CFK-umschnürten Bauteilen aus unbewehrtem oder bewehrtem Beton. Darüber hinaus konnten Aussagen zur tatsächlichen Bruchdehnung der eingesetzten Kohlefasern getroffen und entsprechende Abminderungsfaktoren abgeleitet werden. Unter Berücksichtigung der Datenreihen anderer Forschergruppen wurde die eigene Datenbasis vergrößert und die gewonnenen Erkenntnisse bestätigt. Als Ergebnis steht ein empirischer Bemessungsansatz zur Verfügung, der Bemessungsgleichungen zur Querschnittstragfähigkeit und zugehörigen Dehnung von CFK-umschnürten unbewehrten und bewehrten kreisrunden Stützenquerschnitten bietet. Darüber hinaus können Spannungs-Dehnungs-Beziehungen hergeleitet werden. Durch die Entwicklung von charakteristischen Bemessungsgleichungen gelingt eine einfache Implementierung in bestehende Sicherheitskonzepte. Das entwickelte Modell oder Teile davon eignen sich zur Verwendung in den zur Entstehungszeit der Dissertation vorhandenen Bemessungsvorschriften oder können zu deren Verbesserung herangezogen werden. / This thesis deals with the confinement of short reinforced concrete (RC) columns by carbon-fibre-sheets (CF sheet). In doing so, the connection of concrete surface and CF sheet is enabled by an epoxy resin (CFRP confinement). Thereby, concrete’s lateral expansion is efficiently restricted in cases of imposed axial compressive deformation; therefore, the elastic CFRP resisting response generates an ever increasing lateral compressive stress state on concrete, leading to structural upgrade of the member core to provide a remarkable higher concrete strength and sufficient deformability. Research assignment was to solve open-ended questions and knowledge gaps, which unfolded during an intense literature review, and to present an own proposal of a material model. For this, plain and reinforced concrete columns with different geometrical shape, variable diameter, and different longitudinal and transverse reinforcement elements were produced, and were confined with different CF sheets in variable thickness. Executed deformation controlled compression tests provided investigations concerning the structural behaviour of the test specimens, and electrical measurement techniques such as LVTD and strain gauges enabled a sufficient monitoring of failure modes. The evaluation and interpretation of the received data resulted in empirical equations to predict the ultimate strength and accompanying ultimate axial strain of CFRP confined columns with and without reinforcement. Furthermore, the tests allowed conclusions concerning the rupture strain of the deployed CFRP confinements, and leaded to FRP efficiency factors, capable to predict the actual ultimate strain of the reinforcing fibres. Further data bases, which are available in literature, confirmed the own proposals. As a result, this thesis provides an empirical material model, which deals with proper design equations to predict the load bearing capacity and the deformability of CFRP confined plain and reinforced circular concrete columns. Moreover, it is possible to generate entire stress-strain curves in axial direction. Developed characteristic equations and values allow an easy implementation in existing limit state concepts. The developed model or parts of it are sufficient to be implemented in design guidelines, or they may help to enhance them.
233

Assessment of blood transfusion services in six remote regions in Tanzania

Ndugulile, Faustine Engelbert January 2010 (has links)
Magister Public Health - MPH / Most of the blood transfusion facilities had adequate space, but lacked some of the basic equipment. Blood collected in these facilities was not adequate to meet the blood needs of the regions. These facilities lacked specialised personnel and some of those practicing blood transfusion were not conversant with blood groups, transfusion reactions and the measures to be taken if a reaction occurs. The findings of this study will be used to strengthen blood transfusion services in these hard to reach regions. / South Africa
234

[en] EXPERIMENTAL STUDY ON DUCTILITY OF REINFORCED CONCRETE BEAMS STRENGTHENED IN FLEXURE WITH CARBON FIBER COMPOSITES / [pt] ESTUDO EXPERIMENTAL DA DUCTILIDADE DE VIGAS EM CONCRETO ARMADO REFORÇADAS À FLEXÃO UTILIZANDO COMPÓSITOS COM TECIDO DE FIBRAS DE CARBONO

MARCELIA GOMES MACHADO 12 January 2005 (has links)
[pt] Este trabalho experimental tem como objetivo estudar a ductilidade de vigas retangulares de concreto armado reforçadas à flexão utilizando compósitos com tecido de fibras de carbono. No estudo realizado são apresentados os conceitos clássicos de ductilidade e é proposta uma nova sistemática para obtenção do índice de ductilidade, baseada nas considerações da energia elástica e da energia inelástica. A ductilidade é determinada por meio de um índice energético, que se caracteriza como uma forma mais eficiente para a determinação e análise da ductilidade em elementos estruturais. O programa experimental consistiu no ensaio de sete vigas bi-apoiadas, sendo uma viga de referência e as demais reforçadas à flexão com tecido de fibras de carbono. Todas as vigas possuem as mesmas características mecânicas e geométricas e foram dimensionadas de modo a garantir a ruptura por flexão. A viga de referência, a primeira ensaiada, não foi reforçada e serviu para comparações de incremento de rigidez e resistência após a aplicação do reforço. As vigas reforçadas foram divididas em dois grupos. O grupo A é constituído de duas vigas, reforçadas inicialmente com uma e duas camadas de tecido de fibra de carbono. O grupo B é constituído por quatro vigas que foram reforçadas após um carregamento inicial. Neste grupo, duas vigas foram reforçadas com uma camada de tecido de fibra de carbono e as outras duas foram reforçadas com duas camadas de tecido de fibras de carbono, correspondendo à mesma área total de reforço das anteriores. Todas as vigas foram concretadas, instrumentadas e ensaiadas no Laboratório de Estruturas e Materiais da PUC-Rio. Os ensaios das vigas do grupo B foram realizados com as vigas pré-ensaiadas, reforçadas sob deformação constante e em seguida levadas à ruptura. A deformação foi mantida constante durante a aplicação e o período de cura do reforço. Os resultados obtidos em termos de carga, flecha, momento, curvatura, ductilidade energética e rotação plástica foram analisados. Os estudos realizados mostraram que o reforço com compósitos de fibras de carbono é uma técnica eficaz, que as vigas apresentam ductilidade adequada e que os índices energéticos propostos são adequados para este tipo de estudo. / [en] The objective of this experimental work is to study the ductility of reinforced concrete beams strengthened in flexure using externally bonded carbon fiber fabric composites. This study presents the classic concepts of ductility and proposes a new systematic to obtain the ductility index, which is based on the considerations of elastic and inelastic energy. The ductility was determined by an energetic index, which has seen to be a more efficient method to establish and analyze the ductility of structural elements. The experimental program consisted of seven beams tests. One was used as a control beam without external reinforcement and the others were strengthened with carbon fibers in order to resist flexural load. All the beams had the same mechanical and geometrical characteristics and were designed to fail in flexure. The control beam was not strengthened and its purpose was to compare the stiffness increase and resistance after the strength. The strengthened beams were divided in two groups. Group A was constituted by two beams, initially strengthened by one and two layers of carbon fiber fabric. Group B was formed by four beams which were strengthened after the application of an initial load. In this group, two beams were strengthened by one layer of carbon fiber fabric and the other two were strengthened by two layers, which corresponded to the same area of the others. All the beams were cast, instrumented and tested in the Structural and Materials Laboratory at PUC-Rio. Group B tests were performed with the pretested beams strengthened under constant strain, and then loaded up to rupture. The strain was kept constant during the application and cure of the external reinforcement. The results obtained in terms of load, deflection, resistant moment, curvature, energetic ductility indexes and plastic rotation were analyzed. The study showed that the reinforcement using carbon fiber fabric composites is an efficient technique, the beams presented adequate ductility and the proposed energetic ductility indexes are consistent formulae for this kind of study.
235

Development of Fe-based Superalloys Strengthened by the γ'Phase / γ'相で強化したFe基超合金の開発

Ahmad, Afandi 23 September 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22777号 / 工博第4776号 / 新制||工||1747(附属図書館) / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 乾 晴行, 教授 安田 秀幸, 教授 辻 伸泰 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
236

[pt] ESTUDO EXPERIMENTAL DO REFORÇO À TORÇÃO DE VIGAS DE CONCRETO ARMADO COM COMPÓSITOS DE FIBRAS DE CARBONO / [en] EXPERIMENTAL STUDY OF TORSIONAL STRENGTHENING OF CONCRETE BEAMS WITH CARBON FIBERS COMPOSITES

13 December 2021 (has links)
[pt] Este trabalho de natureza experimental tem como objetivo estudar o comportamento de vigas de concreto submetidas à torção e reforçadas externamente com compósitos de fibras de carbono (CFC). Treze vigas de concreto com 2,0 m de comprimento e seção transversal de 30 cm х 60 cm foram testadas no Laboratório de Estruturas e Materiais do Departamento de Engenharia Civil (LEM/DEC) da Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio). As vigas foram divididas em quatro séries, sendo uma de referência, composta por quatro vigas sem reforço externo, e outras três séries constituídas por três vigas que foram reforçadas externamente com taxas crescentes de estribos de CFC. Com o propósito de estudar a contribuição do concreto e do reforço de CFC na resistência à torção de vigas, a armadura interna só foi colocada na região de aplicação de cargas e nos apoios para evitar a ruptura local e possibilitar o estudo da região central sem a parcela resistente devida à armadura interna de aço. Os resultados dos ensaios mostraram que as vigas reforçadas apresentaram aumento de carga de fissuração entre 16 por cento e 56 por cento e um acréscimo de resistência à ruptura entre 19 por cento e 47 por cento quando comparadas às vigas de referência. A rigidez das vigas na ruptura aumentou proporcionalmente ao crescimento da taxa de reforço como observado em outros ensaios encontrados na literatura. / [en] This research is an experimental study of torsion strengthening of concrete beams with carbon fibers composites. Thirteen concrete beams with 2.0 long and 30 x 60 cm cross section were tested in the Structures and Materials Laboratory of the Civil Engineering Department (LEM/DEC) of Pontifical Catholic University of Rio de Janeiro (PUC-Rio). The beams were divided in four series, the first one was called the reference series and consisted of four beams without external strengthening and each of the other three series was composed of three beams strengthened with increasing rates of external carbon fibers composites stirrups. In oder to allow the study of the central region without the contribution of the steel reinforcement, the internal steel reinforcement was placed only at points of loads application and supports to prevent the local rupture. The tests results showed that the strengthened beams had an increase of the cracking load between 16 per cent and 56 per cent, and an increase of the rupture load between 19 per cent and 47 per cent when compared to the reference beams. The ultimate resistance of the beams increased proportionally to the rate of external carbon fibers composites strengthening, as was observed by other researchers.
237

Zesilování klenbových konstrukcí předpínáním / Strengthening of vaulted structures by prestressing

Požár, Michal Unknown Date (has links)
The topic of this Ph.D. theis is repairing and strengthening of historical wagon vaults (barrel vaults, tunnel vaults) using post tensioning with tendons (monostrands) in longitudinal direction. The vaults should be without an edge, that´s mean the baroque vaults are well appropriate for this method. The pointed barrel vault should be problematic. The stabilization is for a wagon vault created by semicircle or segment part of a circle as well as an elliptic shape. The study has been made for vault with a width of 1 m and for the prestressing force has been used one tendon only. Of course, this method could be apply for normal constructions with a width of many meters. In this case, more tendons should be use with a suitable spacing. The goal of this work was to monitor an experiment model of an wagon vault and a real strengthened baroque vault of a church in Švábenice. During the monitor time, the static Analysis has been made. For these analysis appropriate finite elements in Ansys program has been use. The results of this work is to amplify the knowledge of the real behaviour of strengthened vaults, which could be use like instruction for the civil engineers. Further the public information guide to build an appropriate model of an Vault with an interaction with post-tensioning tendons.
238

Biokompatibilní beta slitiny titanu zpevněné kyslíkem / Oxygen-strengthened biomedical beta titanium alloys

Preisler, Dalibor January 2018 (has links)
Oxygen strengthened biomedical beta titanium alloys Beta titanium alloy Ti-35Nb-6Ta-7Zr-0.7O (wt. %) exhibits a low Young's modulus and high strength thanks to interstitial strengthening effect of oxygen. These mechanical properties are promising for implant production. In this thesis, the aforementioned alloy is thoroughly studied in conditions prepared by various thermomechanical treatments, namely: material after casting, hot compression testing, die-forging, hot rolling and finally, cold-swaged and annealed condition. Mechanical properties and microstructure of prepared conditions are studied with special interest of enhancing the fatigue performance that is poor after casting due to porosity and large grains. The hot rolling was shown to improve the fatigue performance significantly, mainly through grain refinement. It is shown that by combining the effects of cold-swaging and recrystallization annealing, extensive refinement of grain structure can be achieved. Industrial aspects of implant production by the studied methods were discussed. In the second part of the thesis, the possibility of lowering the Young's modulus by reducing the beta phase stability (by reducing of Nb and Ta content), while retaining high strength caused by high interstitial oxyen content is explored. Several alloys were...
239

Hodnoceni efektu fyzioterapie u pacientů po bariatrické operaci / Evaluation of physiotherapeutical effect in patients after bariatric surgery

Trávníčková, Gabriela January 2019 (has links)
Title: Evaluation of physiotherapeutical effect in patients after bariatric surgery. Objectives: The aim of this thesis is to evaluate the effect of physiotherapy (aerobic and anaerobic training) on weight reduction (body composition), quality of life and response to load (affecting VO2 max) in patients after bariatric surgery. After the evaluation of results, I would like to use the study to improve the quality of follow-up care in patients after bariatric surgery. Methods: In this study the search method of available Czech and mainly foreign sources was used. Furthermore, the InBody was used to measure body weight and body composition. For the evaluation of quality of life the standardized questionnaire IWQOL - Lite (HRQoL) was used and the six-minute walk test and spiroergometry were used for the evaluation of response to exercise (VO2 max). Additionally, the spiroergometry evaluated an influence on VO2 max and overall condition in patients after bariatric surgery. The age range of probands was 50 to 64 years. For the analysis of final values a software Microsoft Excel 2007 was used. Results: Two probands participated in the research, one of whom was a woman and one was a man of age 50 and 64 years. One of the probands (proband A) was measured before and after the three-months movement...
240

Textilbeton in Theorie und Praxis: Tagungsband zum 6. Kolloquium zu textilbewehrten Tragwerken (CTRS6); Gemeinsames Abschlusskolloquium der Sonderforschungsbereiche 528 (Dresden) und 532 (Aachen) Berlin, 19.9.2011 – 20.9.2011

Curbach, Manfred, Ortlepp, Regine January 2011 (has links)
Seit nunmehr über einem Jahrzehnt arbeiten die beiden Sonderforschungsbereiche 528 und 532 der Deutschen Forschungsgemeinschaft (DFG) an der Verwendung technischer Textilien im Bauwesen. An der RWTH Aachen (SFB 532) wurde in erster Linie der innovative Verbundwerkstoff „Textilbewehrter Beton“ untersucht, wobei das Ziel dünnwandige und hochbelastbare Betonbauteile waren. An der TU Dresden (SFB 528) wurde in erster Linie die Verwendung von technischen Textilien für die Verstärkung und Instandsetzung von Stahlbetontragwerken oder Holzbauteilen erforscht, um eine wirtschaftlich und technisch attraktive Alternative für die aktuellen Herausforderungen im Bauwesen anbieten zu können. Das 6. Kolloquium zu textilbewehrten Tragwerken (CTRS6) ist Teil einer Serie von Kolloquien, die seit 2001 von den beiden Sonderforschungsbereichen 528 (Dresden) und 532 (Aachen) abwechselnd organisiert werden. Das gemeinsame Abschlusskolloquium der beiden Sonderforschungsbereiche nach dem Ende der Förderung durch die DFG ist das sechste in dieser Reihe und wurde vom Dresdner SFB 528, allerdings diesmal zentral gelegen in Berlin, organisiert. Die Wissenschaftlerinnen und Wissenschaftler der beiden Sonderforschungsbereiche stellten ihre aktuellen Ergebnisse vor, wobei diese von Nachwuchswissenschaftlern aus den einzelnen Teilprojekten präsentiert wurden. Ergänzt wurde das Programm durch Vorträge renommierter internationaler Gastredner auf den Gebieten der Fasern und Textilien. / For more than a decade, the collaborative research centres 528 and 532 of the Deutsche For-schungsgemeinschaft (DFG) have worked on the application of textile fabrics in civil engi-neering. The RWTH Aachen (CRC 532) first and foremost dealt with the innovative composite “textile reinforced concrete” with the aim of developing thin-walled concrete components with a heavy-load capacity. The TU Dresden (SFB 528) concentrated on re-search into the strengthening and restoration of reinforced concrete load-bearing structures or timber components to provide an economically and technically attractive alternative for the current challenges in civil engineering. The sixth colloquium on textile reinforced structures (CTRS 6) is part of a series of colloquia which has been alternately organized by the collaborative research centre 528 (Dresden) and 532 (Aachen).After the DFG’s grant had come to an end, the joint sixth and final colloquium of both collaborative research centres, which was this time organized by the CRC 528 from Dresden, took place in Berlin due to its more central location. The scientists from both col-laborative research centres presented their current results which were explained by young scientists from the individual subprojects. The programme was complemented by presenta-tions by renowned international guest lecturers from the field of fibres and textiles.

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