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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.
391

A history of S.P.G.-supported schools in Newfoundland : 1701-1827 /

White, Gay J. Peddle, January 2001 (has links)
Thesis (M.A.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 299-308.
392

All things to all men popular religious culture and the Anglican Mission in colonial America, 1701-1750 /

Laing, Annette Susan. January 1995 (has links)
Thesis (Ph. D.)--University of California, Riverside, 1995. / Includes bibliographical references (leaves 329-338).
393

Improving and implementing advanced milling techniques for the manufacture of selected titanium aerospace parts

De Bruyn, Ruan 12 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: There is a strong focus on the use of titanium and its alloys in the aerospace industry due to the high ultimate tensile strength and high strength-to-weight ratio of the material. The high performance nature of the material also makes it difficult and costly to machine. South Africa has the second most abundant titanium resources in the world in the form of rutile and ilmenite but no value chain to produce titanium parts from the ore. Currently, the ore is sold overseas at low prices. There exists an initiative to create a full titanium value chain in South Africa by the Department of Science and Technology. This project forms part of this initiative, where local industry is equipped with knowledge and skills to produce and machine titanium parts. The focus of this study is to determine whether it is possible to machine titanium aerospace parts at a local industry partner and equip the industry partner with knowledge and skills in order to facilitate effective and economical machining of these parts. Daliff Precision Engineering was selected as the local industry partner and specific demonstrator parts were selected on which to base the study. The process the industry partner currently uses to machine aerospace parts from difficult-to-machine alloys was studied and evaluated. It was found that about 70% of the machining time was spent on a single roughing process, hence the decision to study the roughing process in an attempt to establish whether improvement was possible. Pilot tests were done at the facilities of the industry partner and time savings of 95% were realised on the roughing process. A 2-level 3-factor Design of Experiments methodology was followed for experimentation and analysis of titanium machining at the industry partner. The roughing process of the demonstrator part was simulated on the CNC machining centre and the depth of cut, cutting speed and feed per tooth were selected as the factors, and the response was tool wear. A statistical analysis was done using Modde 9.1 design of experiments software and an optimisation model was created in order to determine a feasible set of cutting parameters, maximise material removal rate and have a target amount of tool wear. The findings show that it is possible to economically machine titanium aerospace parts with a selected geometry at the industry partner without the need for significant capital investments. The industry partner can use the knowledge generated in this project to validate their titanium machining capabilities and form part of the titanium value chain that is being developed in South Africa. / AFRIKAANSE OPSOMMING: Daar is ‘n groot fokus op die gebruik van titaan allooie in die lugvaart nywerheid, as gevolg van die material se hoë trek-sterkte en hoë sterkte-tot-gewig verhouding. Die eienskappe wat die material so aantreklik maak, is ook die rede wat dit moeilik en duur maak om te masjineer. Suid-Afrika het die tweede grootste titaan reserwes in die wêreld in die vorm van rutiel en ilmeniet erts, maar geen waarde ketting om titaan onderdele te vervaardig van die erts af nie. Die erts word tans oorsee verkoop teen lae pryse. Daar is tans ‘n inisiatief om ‘n titaan waardeketting in Suid-Afrika te skep deur die Departement van Wetenskap en Tegnologie. Hierdie projek vorm deel van hierdie inisiatief om die plaaslike nywerheid toe te rus met kennis en vaardighede om titaan produkte te vervaardig. The fokus van hierdie studie is om te bepaal of dit moontlik is om titaan lugvaart onderdele te masjineer by ‘n plaaslike industrie-vennoot en om hierdie vennoot met kennis en vaardighede toe te rus om hierdie onderdele effektief en ekonomies te vervaardig. Daliff Precision Engineering is gekies as die plaaslike industrie-vennoot en spesifieke demonstrator onderdele is gekies om die studie op te baseer. Die proses wat die industrie-vennoot tans gebruik om moeilik-om-te-masjineer allooie te masjineer is bestudeer en ge-evalueer. Daar was bevind dat 70% van die masjineringstyd bestee word aan ‘n enkele uitrof-proses. Daar is besluit om vas te stel of die uitrof-proses verbeter kan word. Loods-eksperimente is gedoen by die industrie-vennoot se fasiliteite en ‘n tydsbesparing van 95% is gevind op die uitrof-proses. ‘n 2-Vlak 3-faktor eksperimentele ontwerp metodologie is gevolg om eksperimente by die industrie-vennoot op titaan uit te voer en te analiseer. Die uitrof-proses van die demonstrator onderdeel is gesimuleer op die CNC masjineringsentrum en die diepte van snit, snyspoed en voer per tand is gekies as die faktore en beitel-slytasie is gekies as die respons. ‘n Statistiese analise is gedoen deur Modde 9.1 eksperimentele ontwerp sagteware te gebruik om ‘n moontlike stel van sny-parameters te identifiseer om die materiaal-verwyderingstempo te maksimeer en die teiken waarde vir beitel-slytasie te bereik. Daar is gevind dat dit moontlik is on titaan lugvaart onderdele met ‘n spesifieke geometrie ekonomies te masjineer by die industrie-vennoot, sonder om enige beduidende kapitaal uitgawes aan te gaan. Die industrie-vennoot kan die kennis gebruik wat geskep is deur die projek om hulle titaan masjineringsvaardighede te valideer en om deel te vorm van die titaan waardeketting wat besig is om in Suid-Afrika ontwikkel te word.
394

Computing the Greeks using the integration by parts formula for the Skorohod integral

Chongo, Ambrose 03 1900 (has links)
Thesis (MSc (Mathematics))--Stellenbosch University, 2008. / The computation of the greeks of an option is an important aspect of financial mathematics. The information gained from knowing the value of a greek of an option can help investors decide whether or not to hold on to or to sell their options to avoid losses or gain a profit. However, there are technical difficulties that arise from having to do this. Among them is the fact that the mathematical formula for the value some options is complex in nature and evaluating their greeks may be cumber- some. On the other hand the greek might have to be numerically estimated if the option does not posses an explicit evaluation formula. This could be a computationally expensive undertaking. Malliavin calculus offers us a solution to these problems. We can find formula that can be used in combination with Monte Carlo simulations to give results quickly and which are not computationally expensive to obtain and hence give us an degree of accuracy higher that non Malliavin calculus techniques. This thesis will develop the Malliavin calculus tools that will enable us to develop the tools which we will then use to compute the greeks of some known options.
395

Process simulation and optimisation of thin wall injection moulded components

Mullath, Aravind January 2013 (has links)
Integrally moulded hinges and tension bands are important features in packaging components for plastic closures and their function is critically dependent on the flow induced micromorphology in the hinge section. Polymer characteristics and processing of the hinge also have an influence on the hinge properties obtained. This study is aimed at obtaining interrelationships between polymer characteristics, in-cavity flow, microstructure development and hinge properties, to produce hinges with enhanced functional properties. Three different virgin polypropylene (PP) grades were investigated (homopolymer PP-H, random copolymer PP-RC and impact copolymer PP-IC) and injection moulding simulation was carried out using Moldflow software. In-cavity data acquisition has been carried out for different sets of injection moulding conditions, using high performance transducers and a data acquisition system. A comparison between Moldflow simulation and practical injection moulding data suggests that, for thin wall injection moulded components the real time pressure data are in close agreement during the injection stage. During the packing stage there is some disagreement between these data, since the thickness of hinge and tension band sections are 0.4 mm and 0.5 mm respectively, suggesting that these dimensions are extending the capability of the software. An extensive study using a design of experiments (DoE) approach was carried out on both practical and predictive data. Injection velocity and melt temperature were the most influential factors on the component mechanical properties. From the optical micrographs it is observed that PP-RC has a finer micro-structure compared to PP-H and PP-IC and some micrographs confirm Moldflow simulation results in which hesitation effects are evident, as the flow converges into the thin hinge and tension band sections. PP-clay nanocomposites (PP-CN) were prepared using a twin screw compounder. Transmission electron microscopy (TEM) has shown some evidence of dispersion and exfoliation of the clay particles in the PP matrix. However, X-ray diffraction (XRD) results show a reduction in inter-layer spacing of PPCN s possibly due to clay compaction. The addition of nano-clay however has not resulted in any significant improvements in the mechanical properties of hinges and tension bands. The high degree of molecular orientation induced in the hinge and tension-band sections appears to mask any improvements attributed to the addition of nano-clay. From the reprocessed and post consumer recyclate (PCR) study conducted on hinges and tension bands, it is seen that with an increase in both the re-processing and PCR content there is a decrease in the component strength of around 14%, giving scope to potentially use PCR in future packaging applications. Investigations conducted on colour pigments (violet and green) reveal that the onset of crystallisation for green pigmented mouldings is considerably higher (16°C) than for natural and violet mouldings. Optical micrographs also reveal a finer microstructural texture for green components, indicating a high nucleating capability of the green pigment. Irrespective of the colour, both for hinges and tension bands, the yield stress values were around twice as high as the values quoted in the manufacturer s data sheet for isotropic PP, due to the high levels of molecular orientation in the hinge and tension band sections. In order to industrially validate the findings from the DoE study, commercial closures were produced in industry on a production tool then characterised. In the case of tension bands, there was a good agreement between the results obtained from lab scale and industrial study due to the relatively simple geometry. For hinges this agreement is not so clear. Finally a comparison of mechanical properties of the 3 PP grades shows that PP-H has a higher yield stress compared to PP-IC and PP-RC and yield stress is significantly higher (yield strain values are lower) than values quoted by the manufacturer. The PhD study has confirmed the process conditions that are able to optimise all the interactive effects to improve functional properties in high volume parts in the packaging industry.
396

[en] APPLICATION OF RFID TECHNOLOGY IN THE SPARE PARTS SUPPLY CHAIN: A CASE STUDY ON BRAZILIAN NAVY SHIPS / [pt] APLICAÇÃO DA TECNOLOGIA RFID NA CADEIA DE SUPRIMENTO DE SOBRESSALENTES: UM ESTUDO DE CASO EM NAVIOS DA MARINHA DO BRASIL

ROGERIO FERRAZ QUEIROZ MIRANDA 14 February 2017 (has links)
[pt] Atualmente, muitas organizações visam satisfazer as necessidades de clientes eliminando custos. Novas soluções inovadoras são adotadas para incrementar a eficiência da Logística, e em paralelo, reduzir custos operacionais com a utilização de Tecnologia da Informação (TI). A RFID (identificação por radiofrequência) é a TI que proporciona o incremento da integração, da eficiência e da eficácia em toda a cadeia analisada. Embora existam desafios afiançados para a implementação da tecnologia em materiais metálicos, há aplicações desenvolvidas neste nicho, incluindo pesquisas subsidiadas pela Marinha Americana. Benefícios e vantagens da RFID são expostos: incremento da precisão do inventário, redução do custo da mão de obra, mitigação de erros de registro, incremento dos níveis de serviço, aumento da integração e monitoramento de processos logísticos à jusante da cadeia. Neste contexto, este trabalho tem por objetivos analisar a viabilidade de implantação da tecnologia RFID nas Fragatas Classe Niterói - FCN, conservada a compatibilidade com os sistemas correntes, discorrendo as oportunidades contemporâneas, vantagens e benefícios da tecnologia orientada ao incremento da eficiência na cadeia de suprimentos de sobressalentes das FCN; evidenciar o ganho em custo de mão de obra nas operações de armazenagem e o incremento da precisão de inventário; e avaliar os requisitos técnicos e econômicos para a adoção da RFID nas FCN. Conclui-se que o modelo futuro com a RFID é viável e gera Retorno sobre Investimento - ROI de 2,24 utilizando apenas como benefício à redução do custo de mão de obra. Outros benefícios com base em benchmarking são evidenciados. / [en] Currently, many organizations seek to satisfy the needs of customers by eliminating costs. New innovative solutions are adopted to improve the efficiency of Logistics, and in parallel, reduce operational costs with the adoption of Information Technology (IT). RFID (radio frequency identification) is the IT that provides the improvement of integration, efficiency and effectiveness throughout the chain analyzed. Although there are challenges bailed by the technology implementation in metallic materials, there are applications developed on this niche, including researches subsidized by the U.S. Navy. Benefits and advantages of RFID are exposed: improvement of the inventory accuracy, reduction of the cost of labor, mitigation of registry errors, increase service levels, increase of the integration and of logistics processes monitoring towards the downstream chain. In this context, this paper aims to analyze the feasibility of RFID deployment technology in the Niterói Class Frigates - FCN, preserving the compatibility with the current systems, discussing contemporary opportunities, advantages and benefits of technology oriented to increase the efficiency of the FCN spare parts supply chain; show the gain in the cost of labors in warehouse operations and the improvement of the inventory accuracy; and evaluate the technical and economical requirements for the adoption of RFID in the FCN. We conclude that the future model with RFID is feasible and generate Return on Investment (ROI) of 2.24 using only as benefit the decreasing labor cost. Other benefits based on benchmarking are highlighted.
397

Typy adverbií v jazyce barokních textů a jejich vývoj / Types of adverbs in the language of baroque texts and their development

KLIMEŠOVÁ, Markéta January 2018 (has links)
Adverbs constitute an important element in expressing circumstances. In our dissertation we try to present various types of adverbs in the language of texts which date back to 17th and 18th centuries (so-called Baroque period). The word-formation aspect of these adverbs and the development of their meaning are emphasized. Different semantic shifts of adverbs are observed as well as their usage with functions of different parts of speech (usually particles or conjunctions). The development of adverbs found in Baroque texts is compared both with older language period and with some results of their development in contemporary Czech.
398

Částice v moderní vietnamštině / Particals in moder vietmese language

Slavická, Binh January 2016 (has links)
This doctoral thesis is concerned with particles in modern Vietnamese. Although Vietnamese particles form a small group of synsemantic words, they play a very important role in expressing the attitude of the speaker to the hearer/listener and to the message content as well as expressing grammatical and modal relationships within the sentence. The group includes particles positioned at the end of the sentence, particles appearing before a word as well as at the beginning of a phrase or a sentence. Despite their important function, particles in Vietnamese still are a scarcely explored topic. Particles have been explored usually as part of grammar books; so far, there are only few monographs on the topic of particles. Almost all works deal with a small number of particles and focus especially on those appearing at the end of the sentence. This work is concerned with particles at the end of the sentence as well as particles preceding a word, a phrase, or a sentence. It examines whether particles in Vietnamese are a part of speech at all; it sets forth criteria for classification of particles; it performs their analysis based on actual situations where they appear and describes their semantic characteristics; furthermore, it offers a chart of particles including their possible combinations. Besides, the...
399

Estratégias de relativização e classe de palavra : um estudo tipológico-funcional /

D'Alarme Gimenez, Amanda. January 2011 (has links)
Orientador: Roberto Gomes Camacho / Banca: Angel Humberto Corbera Mori / Banca: Sandra Denise Gasparini Bastos / Resumo: Este trabalho estuda a relação entre a modificação sintática mediante o uso de orações relativas e de adjetivos e a organização morfossintática das línguas da amostra no que se refere às classes de palavras, com o intuito de conduzir a uma generalização tipológica. A hipótese que se investiga é a da possível correlação entre ausência de adjetivo como classe de palavra e ausência de oração relativa como construção a serviço da modificação nominal. A principal consequência dessa correspondência é a de o nome assumir a função modificadora do adjetivo e a construção nominalizada, a função modificadora da oração relativa. Assim, duas situações alternativas são investigadas nesta pesquisa, já que parece tanto improvável que uma língua empregue uma estratégia de relativização diferente de nominalização quando ela não dispõe de adjetivos enquanto classe morfológica como provável a situação inversa, em que a ausência de adjetivos é suprida por uma oração relativa no papel de modificador nominal. Para a realização deste trabalho, adota-se o enfoque funcional, essencialmente empírico, e os dados coletados são analisados por meio de comparação translinguística. O levantamento dos dados foi realizado em duas etapas: a primeira se refere à descrição da oração relativa em cada língua indígena, destacando a estratégia de relativização empregada por ela; e a segunda, à descrição das classes de palavra nessas línguas, especialmente a dos adjetivos e a dos advérbios, posições sintaticamente mais complexas. Por se tratar de uma investigação de cunho tipológico, o corpus de análise deve ser representativo, ou seja, as línguas que o compõem devem ser distantes genética, geográfica e tipologicamente. O corpus deste trabalho é composto por 30 línguas indígenas, previamente descritas em gramáticas, teses ou em outros... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This paper studies both the relationship between syntactic modification through the use of relative clauses and adjectives and the morphosyntactic organization of the sample languages with respect to parts of speech, in order to lead to a typological generalization. In this sense, the hypothesis under investigation is the possible correlation between the absence of the adjective as a word class and the absence of relative clauses as a construction for the nominal modification. The main consequence of this correspondence is that the noun assumes the modifier function of the adjective and that the nominalized construction assumes the modifier function of the relative clause. Thus, two alternative scenarios are investigated in this research, since it seems unlikely that a language employs a strategy of relativization different from the nominalization one when it does not have adjectives as a morphological class as likely the reverse situation, in which the absence of adjectives is supplied by a relative clause on the role of a nominal modifier. For this work, we adopt the functional approach, essentially empirical, in which data is collected by means of translingual comparison. The data collection was conducted in two stages: the first refers to the description of the relative clause in every Indian language, highlighting the strategy of relativization employed by it; and the second refers to the description of word classes in these languages, especially adjectives and adverbs, which take positions that are syntactically more complex. Because this is a typological investigation, the corpus of analysis must be representative, i.e. the languages under investigation must be genetically, geographically and typologically distant. The corpus of this work consists of 30 indigenous languages, previously described in grammar books, theses or in other descriptive materials such as manuals... (Complete abstract click electronic access below) / Mestre
400

Modelo de gerenciamento de estoques de pe?as de reposi??o para empresas de transporte urbano de passageiros / A spare parts stock management model to companies of urban passenger transport by bus

Fernandes, Roberto Klecius Mendon?a 22 December 2010 (has links)
Made available in DSpace on 2014-12-17T14:52:58Z (GMT). No. of bitstreams: 1 RobertoKMF_DISSERT.pdf: 1712911 bytes, checksum: 4a2d9da3d58d19eb0b246c2f5c1cf027 (MD5) Previous issue date: 2010-12-22 / This work searches to offer a model to improve spare parts stock management for companies of urban passenger transport by bus, with the consequent progress in their maintenance management. Also known as MRO items (Maintenance, Repair and Operations), these spare parts, according their consumption and demand features, cost, criticity to operation, lead-time, quantity of suppliers, among other parameters, shouldn?t have managed their inventory like normal production items (work in process e final products), that because their features, are managed by more predictable models based, for example, in economic order quantity. In the case specifically of companies of urban passenger transport by bus, items MRO have significant importance in their assets and a bad management of these inventories can cause serious losses to company, leading it even bankrupticy business, in more severe situations which missing spare part provokes vehicles shutdown indefinitely. Given slight attention to the issue, which translates in little literature available about it when compared to that literature about normal items stocks, and due the fact that MRO items be critical to bus urban transport of passengers companies?, it is necessary, so, deepen in this theme searching to give technical and scientific subsidies to companies that work, in many times, empirically, with these so decisive inputs to their business. As a typical portfolio problem, in which there are n items, separated into critical and noncritical, while competing for the same resource, it was developed a new algorithm to aid in a better inventory management of spare parts used only in corrective maintenance (whose failures are unpredictable and random), by analyzing the cost-benefit ratio, which compares the level of service versus cost of each item. The model was tested in a company of urban passenger transport by bus from the city of Natal, who anonymously provided their real data to application in this work / O trabalho busca oferecer um modelo para melhor gest?o do estoque de pe?as de reposi??o para empresas de transporte urbano de passageiros, com a conseq?ente melhoria na gest?o das suas manuten??es. Tamb?m conhecidos como itens MRO (Manuten??o, Reparo e Opera??es), estas pe?as de reposi??o, em fun??o das suas caracter?sticas de consumo e demanda, custo, criticidade para a opera??o, tempo de ressuprimento, quantidade de fornecedores, entre outros par?metros, n?o devem ter seus estoques geridos como itens normais de produ??o (bens intermedi?rios e produtos acabados), que pelas suas caracter?sticas, s?o regidos por modelos mais previs?veis baseados, por exemplo, no lote econ?mico de compra. Em se tratando especificamente de empresa de transporte urbano de passageiros por ?nibus, os itens MRO t?m peso significativo nos seus ativos e a m? gest?o deste estoque pode causar s?rios preju?zos ? companhia, levando-a, em situa??es mais graves em que a pe?a faltante resulte em parada de ve?culos por tempo indeterminado, at? ? fal?ncia do neg?cio. Face ? discreta aten??o ao tema, o que se traduz na pouca literatura dispon?vel sobre o mesmo quando comparada ?quela relacionada aos estoques de itens de produ??o, e devido ao fato dos itens MRO serem cr?ticos para as empresas de transporte urbano de passageiros, faz-se necess?rio, pois, o aprofundamento no assunto buscando dar subs?dios t?cnico-cient?ficos ?s firmas que trabalham, muitas vezes de forma emp?rica, com estes insumos t?o decisivos para o seu neg?cio. Tendo-se um t?pico problema de portf?lio, no qual existem n itens, segregados em cr?ticos e n?o-cr?ticos, competindo simultaneamente pelo mesmo recurso, foi desenvolvido um novo algoritmo para auxiliar na melhor gest?o do estoque de pe?as de reposi??o utilizadas somente em manuten??es corretivas (cujas falhas s?o imprevis?veis e aleat?rias), atrav?s da an?lise da rela??o custo-benef?cio, onde comparam-se n?vel de servi?o versus custo de cada item. O modelo foi testado em uma empresa de transporte urbano de passageiros por ?nibus da cidade de Natal, que anonimamente, forneceu seus dados reais para aplica??o neste trabalho

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