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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.
171

Investigation of the influence of gasoline engine induction system parameters on the exhaust emission

Kauffmann, Joseph Chester January 1972 (has links)
No description available.
172

MULTI-PLATFORM IMPLEMENTATION OF SPEECH APIS

Manukyan, Karen 21 August 2008 (has links)
No description available.
173

[pt] AVALIAÇÃO DA TENACIDADE E PREVISÕES DE FRATURAS EM MATERIAIS ELASTOPLÁSTICOS / [en] TOUGHNESS EVALUATION AND FRACTURE PREDICTIONS IN ELASTOPLASTIC MATERIALS

EDUARDO ENES COTA 05 October 2020 (has links)
[pt] Compreender como analisar trincas é essencial para a indústria petroquímica evitar qualquer incidente de uma forma econômica. Normas de Integridade Estrutural fornecem procedimentos conservadores para avaliar componentes trincados como tubulações e vasos de pressão. Portanto, previsões de cargas criticas foram calculadas assumindo uma placa com trinca passante seguindo procedimentos dos níveis 2 e 3 da API 579. Para comparação, testes experimentais foram realizados para avaliar o conservatismo da norma em falha por rasgamento dúctil. Além disso, a tenacidade à fratura foi medida por meio do JIc e curva J-R. A técnica usada durante o processo de fratura foi o método de flexibilidade elástica com descarregamento e carregamentos sequenciais. Adicionalmente, efeito de geometria e tipo de carregamento, os quais possuem grande influência nas medições de tenacidade, também foram avaliados usando conceitos da mecânica da fratura elastoplástica. O material utilizado nesse trabalho foi o API 5L X80, que é um aço de Alta Resistencia e Baixa Liga (ARBL) bifásico desenvolvido para tubulações aplicáveis em aguas profundas. Os ensaios experimentais de medição de tenacidade usando corpos de prova SE(B), que possuem média-alta restrição plástica, foram testados seguindo procedimentos da ASTM E1820-17. Já os experimentos usando corpos de prova SE(T), que possuem baixa restrição plástica, foram realizados considerando procedimentos da literatura. / [en] Understanding how to analyze cracks is essential for the petrochemical industry to avoid accidents or incidents in a safe and economical way. Structural Integrity standards provide conservative procedures to assess the actual strength of cracked components like pipes and pressure vessels. Therefore, critical loads predictions were computed on a plate with a through-wall crack following level 2 and 3 of the fitness-for-service guide API 579. For comparison, experimental tests were performed to evaluate the standard conservatism on a ductile tearing type of failure. Furthermore, the fracture toughness of the steel was measured through standard JIc tests and material s resistance curves (J-R curve). The technique used during the fracturing process was the elastic compliance method with unloading/reloading sequences. Additionally, the effects of the specimen s geometry and the type of loading, which can significantly change the value of its toughness, were also analyzed using concepts of elastoplastic fracture mechanics. The material used in this work was the API 5L X80, which is a High Strength Low Alloy (HSLA) dual-phase steel developed for deepwater pipelines. The fracture toughness measurement tests using SE(B) specimens, which have a medium-to-high plastic constraint, followed the ASTM E1820-17 procedures. The experiments with SE(T) specimens, which present a low plastic restriction, considered literature procedures.
174

Gamification of reading aloud using Godot and Web speech / Spelifiering av högläsning genom användning av Godot och Web Speech

Ali Kadhum, Bashir January 2022 (has links)
Immersion is a subject studied in various areas and especially in games, since a game that immerses a player, counts as a game of great value. Many studies have been performed to understand how to measure immersion through various forms of questionnaires, but how can one with the help of gamification and loud reading make reading more immersive? To see if gamification and loud reading can make reading more immersive an application is developed, the application provides a paragraph, and when read loud correctly creates sound and shows images. Then the application is tested by a group of people to see if gamification can be used to bring life to reading and further immerse the reader in the world of books.
175

Unga vuxnas val av betalningsmetoder: En analys avkodkomplexitet för betalmetoder i en spar-applikation / Young Adults' Choice of Payment Methods: AnAnaysis of Code Complexity in a saving application

Fredholm, Alexander, Vo, Ta Quang January 2024 (has links)
I detta examensarbete utforskas vilka överförings- och betalningsmetoder ungavuxna föredrar av Swish, Klarna och Tink samt tekniska implementering gällandekodkomplexitet för dessa överförings- och betalningsmetoder. Detta är viktigt för attkunna erbjuda överförings- och betalningsmetoder som unga vuxna känner sigtrygga med och till att denna målgrupp fortsätter gå mot ett kontantfritt samhälle.Studien syftar till att fylla det forskningsgap som finns kring en direkt jämförelse avdessa betalningsmetoder.Forskningen visar att unga vuxna föredrar metoder som är användarvänliga och harett starkt varumärkesrykte. Forskningen visar också behovet av att vända sigspecifikt till unga vuxna då dessa saknar finansiell kunskap inom området.En prototyp utvecklades för att jämföra kodkomplexitet mellan de mest populärabetalningsmetoderna Swish, Klarna och Tink. Kodkomplexiteten förimplementeringen av dessa metoder mättes med Cyclomatic Complexity, ochresultaten visade att Swish, Klarna och Tink alla har en liknande implementering viaAPI-anrop i sin enklaste form, vilket innebär att valet mellan dem inte innebär någonskillnad i kodkomplexitet.Utifrån jämförandet av kodkomplexitet valdes en komplett prototyp att utvecklas föratt funktionstesta en implementetion av Tink, med hjälp av Quarkus för logik-delenkallad backend och SwiftUI för utseende-delen kallad frontend. SwiftUI valdes föratt skapa en dynamisk och användarvänlig gränssnittsupplevelse för Apple-enheter,medan Quarkus valdes för sin robusthet och effektivitet på server sidan.Prototypen funktionstestades och utvärderades av produktägaren Peak AMSecurities AB. Resultatet blev att prototypens kodbas kan användas i framtidaproduktionssättning.Denna studie bidrar till insikt om unga vuxnas preferenser för digitalabetalningsmetoder och erbjuder en teknisk grund för vidare forskning inomområdet. Genom att jämföra Swish, Klarna och Tink ger arbetet viktiga insikter somkan hjälpa utvecklare att skapa bättre finansiella verktyg som möter användarnasbehov och förväntningar. / This thesis explores which transfer methods young adults prefer among Swish,Klarna, and Tink, as well as the technical implementation concerning code com-plexity for these transfer and payment methods. This is important to offer transferand payment methods that young adults feel comfortable with and to ensure thistarget group continues to move towards a cashless society. The study aims to fill theresearch gap regarding a direct comparison of these payment methods.Research shows that young adults prefer methods that are user-friendly and have astrong brand reputation. The research also highlights the need to specifically ad-dress young adults as they lack financial knowledge in the area.A prototype was developed to compare code complexity with the most popular pay-ment methods Swish, Klarna, and Tink. The code complexity for the implementa-tion of these methods was measured using Cyclomatic Complexity, and the resultsshowed that Swish, Klarna, and Tink all have similar implementations via API callsin their simplest form, which means they do not increase code complexity for devel-opers.Based on the comparison of code complexity, a complete prototype was chosen tobe developed for functional testing, implemented with Tink, using Quarkus for thebackend logic and SwiftUI for the frontend interface. SwiftUI was chosen to createa dynamic and user-friendly interface experience for Apple devices, while Quarkuswas chosen for its robustness and efficiency in server-side processing.The prototype was functionally tested and evaluated by the product owner Peak AMSecurities AB. The result was that the prototype's codebase can be used in futureproduction deployment.This study contributes to the understanding of young adults' preferences for digitalpayment methods and provides a technical foundation for further research in thearea. By comparing Swish, Klarna, and Tink, the work offers important insightsthat can help developers create better financial tools that meet users' needs and ex-pectations.
176

Labyrinth Seal Preprocessor and Post-Processor Design and Parametric Study

Mehta, Rumeet Pradeep 03 June 2008 (has links)
Vibrations caused due to aerodynamic excitation may cause severe limitation to the performance of turbomachines. The force resulting from the non-uniform pressure distribution within the labyrinth cavity is identified as a major source of this excitation. In order to perform rotor dynamic evaluation of rotor-bearing-seal system, accurate prediction of this force is essential. A visual basic based front-end, for a labyrinth seal analysis program, has been designed herein. In order to accurately predict the excitation force, proper modeling of labyrinth leak path is important. Thus, the front-end developed herein incorporates a leak-path geometric diagram for visual analysis of labyrinth leak path and tooth location. Furthermore, to investigate influence of various operating conditions and gas properties on excitation force (effective cross-coupling stiffness), a parametric study is performed on both the eye seal and the balance piston labyrinth seal. / Master of Science
177

Implementing an Application Programming Interface for Distributed Adaptive Computing Systems

Yao, Kuan 12 June 2000 (has links)
Developing applications for distributed adaptive computing systems (ACS) requires developers to have knowledge of both parallel computing and configurable computing. Furthermore, portability and scalability are required for developers to use innovative ACS research directly in deployed systems. This thesis presents an Application Programming Interface (API) implementation developed in a scalable parallel ACS system. The API gives the developer the ability to easily control both single board and multi-board systems in a network cluster environment. The API implementation is highly portable and scalable, allowing ACS researchers to easily move from a research system to a deployed system. The thesis details the design and implementation of the API, as well as analyzes its performance. / Master of Science
178

Ontological Reasoning with Taxonomies in RDF Database / Ontological Reasoning with Taxonomies in RDF Database

Hoferek, Ondřej January 2013 (has links)
13548805670613-46162052c208770f99e83a586780d16c.txt As the technologies for the realisation of the idea of the Semantic Web have evolved rapidly during past few years, it is possible to use them in variety of applications. As they are designed with the ability to process and analyze semantic information found in the data in mind, they are particularly suitable for the task of enhancing relevance of the document retrieval. In this work, we discuss the possibilities of identifying a suitable subset of the expressing capabilities of the SPARQL querying language and create a component that encapsulates the technical details of its usage. Page 1
179

Caracterização microestrutural do Aço API 5L X65 soldado por feixe de elétrons com diferentes aportes térmicos / Microstructural characterization of API 5L X65 steel welded by electron-beam with different heat inputs

Monte, Isabel Rocha do 01 July 2013 (has links)
Esta Dissertação abrange a caracterização microestrutural do aço API 5L X65 soldado por feixe de elétrons (EBW) com cinco diferentes aportes térmicos e sem o uso de metal de adição. O aço API 5L X65 pertence à classe de aços ARBL e é empregado na fabricação de oleodutos e gasodutos. As três regiões da solda metal-base (MB), zona termicamente afetada (ZTA) e zona fundida (ZF) foram caracterizadas por microscopia ótica (MO), microscopia eletrônica de varredura (MEV), difração de raios X e medidas de microdureza Vickers. As microestruturas encontradas nestas três regiões são bastante distintas. O MB apresenta grãos ferríticos com bandas perlíticas orientadas paralelamente à direção de laminação. Devido à elevada densidade de potência do processo EBW e às elevadas velocidades de soldagem utilizadas, a ZTA é bastante estreita sendo formada por grãos ferríticos finos e bandas perlíticas degeneradas que a diferem do MB. Na interface ZTA/ZF foi possível observar a presença de grãos com morfologia acicular com a presença dos constituintes M-A (martensita-austenita). A ZF apresentou morfologia similar à encontrada em aços microligados soldados: ferrita alotriomórfica, ferrita acicular, ferrita de Widmanstätten, constituintes M-A, além de regiões bainíticas. Na parte central da chapa foi observada a segregação de manganês. A técnica EBW permite a soldagem de tubos com paredes espessas com apenas um passe. Os resultados desta Dissertação são úteis para avaliar a viabilidade técnica do uso de EBW na fabricação de tubos para o transporte de óleo e gás, especialmente em aços mais resistentes (bainíticos). / This Dissertation aims at the microstructural characterization of electron-beam welded (EBW) API 5L X65 steel using five different processing conditions (heat input) and without filler metal addition. The API 5L X65 steel is a high-strength low-alloy (HSLA) steel employed mainly in the manufacture of pipelines for oil and gas. The three regions of the welds, namely the base metal (BM), heat affected zone (HAZ) and fusion zone (FZ) were characterized by light optical microscopy using different chemical etching agents, scanning electron microscopy, X-ray diffraction and Vickers microhardness testing. The microstructures found in the three regions were quite distinct. The BM consists of elongated ferritic grains with pearlite bands oriented along the rolling direction. Due to the high power density provided by EBW, the HAZ is very narrow and consists of ferritic grains and bands of degenerated pearlite. At the HAZ/FZ interface it is possible to observe the presence of grains with acicular morphology and the presence of M-A (martensite- retained austenite) constituents. The FZ showed a morphology similar to that one found in molten microalloyed steels consisting of allotriomorphic ferrite, acicular ferrite, Widmanstätten-like ferrite, M-A constituents, as well as bainite. In the central part of the plate it was observed the presence of Mn-segregation lines along the BM. The electron beam welding was chosen because it produces a relatively small HAZ and it allows the welding of thick-wall tubes in one single pass. The results of this work are useful to evaluate the possibility of using EBW in the manufacture of pipelines for transport of oil and gas, especially in higher grade steels.
180

Simulação física e caracterização de zonas afetadas pelo calor de aços API 5L grau X80. / Physical simulation and characterization on heat affected zones of API 5L grade X80 steels.

Sanchez Chavez, Giancarlo Franko 07 October 2011 (has links)
Os aços para tubos API 5L X80 são aços de alta resistência e baixa liga (ARBL) usados na fabricação de tubos para o transporte de gás e petróleo conduzidos através de dutos. Os tubos API 5L X80 se caracterizam por terem excelentes propriedades mecânicas como resistência à tração, tenacidade, ductilidade e resistência à corrosão, além de boa soldabilidade. Estes tubos trazem muitos benefícios como, por exemplo, o fator econômico já que ao ter boa resistência mecânica estes tubos podem ser fabricados com espessuras de parede menores. Estas reduções nas espessuras diminuem os custos de transporte, construção, soldagem e instalação. Além disso, estes tubos podem ser fabricados com grandes diâmetros, permitindo o transporte de grandes quantidades de fluidos a elevadas pressões e vazões. A tenacidade confere ao material a propriedade de ser resistente à fratura frágil, uma vez que estes tubos em sua maioria trabalham em condições ambientais severas. O objetivo deste trabalho é simular fisicamente e estudar as propriedades mecânicas de regiões da zona afetada pelo calor (ZAC) produzidas por diferentes ciclos térmicos, que ocorrem quando o tubo é fabricado e o duto montado. A ideia foi estudar a ZAC produzida no tubo fabricado pelo processo UOE (solda longitudinal) e a solda feita no campo quando o tubo é montado (solda circunferencial) além da ZAC na intersecção entre a soldagem longitudinal e circunferencial. Foram usinados corpos-de-prova nas orientações L-T e T-L e com o cordão de solda longitudinal do tubo no centro. Estes corpos-de-prova foram submetidos a quatro ciclos térmicos únicos com temperaturas máximas de 650, 800, 950 e 1300 °C e ciclos térmicos multipasse 950-800 e 950-800- 650 °C. Estes corpos-de-prova foram submetidos a diferentes ensaios e caracterizações. Foram feitos ensaios de impacto a 0 °C, as superfícies fraturadas foram analisadas no MEV e mediu-se a expansão lateral produzida pelo ensaio de impacto. Mediu-se a dureza da microestrutura por meio do ensaio Vickers com 300g de carga. A microestrutura da ZAC foi caracterizada por microscopia óptica, com ataque convencional e ataque colorido Klemm, e microscopia eletrônica de varredura. Metalografia quantitativa foi usada para obter a quantidade de perlita na matriz dos corpos-de-prova. A trajetória da fratura na microestrutura dos corpos-de-prova simulados, provocada pelo ensaio Charpy, foi analisada com microscopia óptica e eletrônica de varredura. Os resultados mostraram que as energias absorvidas no ensaio de impacto pelos corpos-de-prova simulados cumprem com os requisitos exigidos pela norma API 5L para o metal base sem simulação e que as microestruturas observadas variam segundo o tipo de ciclo térmico aplicado a cada posição do tubo. / API 5L Grade X80 steel are high strength low alloy steels (HSLA) used in the manufacture of pipes for transporting oil and gas by pipelines. API 5L X80 pipes are characterized by having excellent mechanical properties such as tensile strength, toughness, ductility, corrosion resistance, and good weldability. These pipes bring many benefits, for example, the economic factor related to the good mechanical strength of these tubes which can be produced with smaller wall thicknesses. This reduction in thickness lowers costs for transportation, construction, welding and installation. In addition, these tubes can be fabricated with large diameters, allowing the transport of large amounts of fluids at high pressures and flow rates. The toughness gives, to this material, the characteristic of being resistant to brittle fracture, since these tubes mostly work in aggressive environmental conditions. The objective of this work is to physically simulate and study the mechanical properties of regions of the heat affected zone (HAZ) produced by different thermal cycles, which occur when the duct pipe is manufactured and assembled. The idea was to study the HAZ produced in the pipe manufactured by the UOE process (longitudinal weld) and the welding done in the field when the tube is mounted (HAZ beyond the intersection between the longitudinal and circumferential welding). Charpy V samples were machined in the L-T and T-L orientations and in the longitudinal weld in the center of the tube. These samples were subjected to single thermal cycles with maximum temperatures of 650, 800, 950 and 1300°C and multipass thermal cycling with maximum temperatures of 950-800 and 950-800-650°C. The samples were subjected to different tests and characterizations. Impact tests were made at 0°C, measured the lateral expansion produced and the surface fracture were examined under SEM. Vickers 300g microhardness was also measured in the simulated HAZ region. The microstructure of the HAZ was characterized by optical microscopy with conventional etching and Klemm colorful etching, and scanning electron microscopy. Quantitative metallography was used to obtain the amount of pearlite in the matrix of samples. The Charpy V fracture propagation path trajectory in the simulated microstructure was analyzed with optical microscopy and scanning electron microscopy. The results showed that the Charpy V absorbed energy by the simulated samples complies with the requirements of the API 5L standard for the base metal without simulation and the HAZ observed microstructures vary according to the thermal cycle type applied to each tube position.

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