15 research outputs found

    Aeronautical engineering: A continuing bibliography with indexes (supplement 321)

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    This bibliography lists 496 reports, articles, and other documents introduced into the NASA scientific and technical information system in Sep. 1995. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment, and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics

    The Manufacture of Marine Propellers in Moulded Anisotropic Polymer Composites

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    This thesis examines the feasibility of manufacturing small marine propellers from continuous fibre reinforced polymer composite materials. An appraisal of some current applications of composite materials in the marine industry is given, together with the moves shown towards the use of composites in the area of propeller design. It has been shown that manufacturing propellers in composite materials is theoretically more cost effective than traditional materials. The manufacturing route investigated is Resin Transfer Moulding, where some detailed investigations have highlighted some of the critical processing parameters necessary for successful production of laminates suitable for propellers and other high performance marine structures. A thorough testing programme of 4 novel designs of composite propeller is reported. Trials at sea on university run vessels has enabled many hours use to be logged, which has shown the fitness for purpose of propellers made from glass reinforced, epoxy composite. Experimental tank testing has helped to shape the remainder of the research by identifying the possibility of using hydroelastic tailoring to improve the efficiency of the propeller when a variety of operating conditions are required from the propulsion system. Further experience is required with respect to the the tooling construction and the life assessment of the propeller. To facilitate appropriate modelling of the propeller, spreadsheet based load prediction models have been used. Finite element analysis (FEA) was used to model the elastic characteristics of one particular design of novel composite propeller. This indicated that traditional geometries may be too stiff to allow significant performance advantages from the anisotropy of the material. However the potential does exist for modified propeller geometries made from composite to give some performance benefit. For specific applications, small marine propellers made from continuous glass fibre reinforced epoxy composite are likely to yield cost savings over traditional propeller materials

    A novel access pattern-based multi-core memory architecture

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    Increasingly High-Performance Computing (HPC) applications run on heterogeneous multi-core platforms. The basic reason of the growing popularity of these architectures is their low power consumption, and high throughput oriented nature. However, this throughput imposes a requirement on the data to be supplied in a high throughput manner for the multi-core system. This results in the necessity of an efficient management of on-chip and off-chip memory data transfers, which is a significant challenge. Complex regular and irregular memory data transfer patterns are becoming widely dominant for a range of application domains including the scientific, image and signal processing. Data accesses can be arranged in independent patterns that an efficient memory management can exploit. The software based approaches using general purpose caches and on-chip memories are beneficial to some extent. However, the task of efficient data management for the throughput oriented devices could be improved by providing hardware mechanisms that exploit the knowledge of access patterns in memory management and scheduling of accesses for a heterogeneous multi-core architecture. The focus of this thesis is to present architectural explorations for a novel access pattern-based multi-core memory architecture. In general, the thesis covers four main aspects of memory system in this research. These aspects can be categorized as: i) Uni-core Memory System for Regular Data Pattern. ii) Multi-core Memory System for Regular Data Pattern. iii) Uni-core Memory System for Irregular Data Pattern. and iv) Multi-core Memory System for Irregular Data Pattern.Les aplicacions de computació d'alt rendiment (HPC) s'executen cada vegada més en plataformes heterogènies de múltiples nuclis. El motiu bàsic de la creixent popularitat d'aquestes arquitectures és el seu baix consum i la seva natura orientada a alt throughput. No obstant, aquest thoughput imposa el requeriment de que les dades es proporcionin al sistema també amb alt throughput. Això resulta en la necessitat de gestionar eficientment les trasferències de memòria (dins i fora del chip), un repte significatiu. Els patrons de transferències de memòria regulars però complexos així com els irregulars són cada vegada més dominants per a diversos dominis d'aplicacions, incloent el científic i el processat d'imagte i senyals. Aquests accessos a dades poden ser organitzats en patrons independents que un gestor de memòria eficient pot explotar. Els mètodes basats en programari emprant memòries cau de propòsit general i memòries al chip són beneficioses fins a cert punt. No obstant, la tasca de gestionar eficientment les transferències de dades per a dispositius orientats a throughput pot ser millorada oferint mecanismes hardware que explotin el coneixement dels patrons d'accés de les aplicacions, així com la planificació dels accessos a una arquitectura de múltiples nuclis. Aquesta tesis està enfocada a explorar una arquitectura de memòria novedosa per a processadors de múltiples nuclis, basada en els patrons d'accés. En general, la recerca de la tesis cobreix quatres aspectes principals del sistema de memòria. Aquests aspectes són: i) sistema de memòria per a un únic nucli amb patrons regulars, ii) sistema de memòria per a múltiples nuclis amb patrons regulars, iii) sistema de memòria per a un únic nucli amb patrons irregulars, iv) sistema de memòria per a múltiples nuclis amb patrons irregulars

    Management by objectives in European public employment services

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    "This paper surveys and compares national experience with performance management in European public employment services (PES) in the form of 'management by objectives' (MBO). Part I of this paper reviews the relevant performance management literature and defines key terms. Part II presents the results of a stocktaking survey of the use of operational objectives, performance indicators, benchmarking and related managerial practices in all 15 EU member states and Norway. Part III reports the results of a comparative analysis and more in-depth assessment of national experience with management by objectives in Austria, France, Great Britain, and Sweden. Part IV summarizes principal findings and presents main conclusions. Ten of the eighteen PES organizations surveyed were found to use management by objectives: Austria, Denmark, the Flanders regional PES (VDAB) in Belgium, France, Germany, Great Britain, Finland, the Netherlands, Norway, and Sweden. In summary, the impact of MBO-systems depends strongly on design and implementation features. If based on principles of 'good-practice', MBO can improve the efficiency and effectiveness of PES operations." (author's abstract)"In diesem Papier wird eine Bestandsaufnahme zu Verbreitung und Praxis der Zielsteuerung (Management by Objectives, MBO) in europäischen Arbeitsverwaltungen vorgelegt. Teil I rekapituliert die relevante Forschungsliteratur und entwirft einen analytischen Bezugsrahmen. In Teil II wird ein empirischer Überblick zur Steuerung mittels Zielen und Indikatoren in europäischen Arbeitsverwaltungen gegeben. Unter 18 Arbeitsverwaltungen sind Zielsteuerungsansätze für die zehn Länder Dänemark, Deutschland, Finnland, Flandern (VDAB), Frankreich, Großbritannien, Niederlande, Norwegen, Österreich, und Schweden nachzuweisen. Teil III vergleicht vertiefend die Managementansätzen in den Arbeitsverwaltungen Österreichs, Großbritanniens, Frankreichs und Schwedens. Für den Erfolg (oder Mißerfolg) der Zielsteuerung sind Design- und Implementationsfaktoren entscheidend. Wenn Prinzipien 'guter Praxis' beachtet werden, kann die Effektivität und Effizienz der Arbeitsverwaltung mittels MBO gesteigert werden." (Autorenreferat

    Network relationships and the internationalisation of the tourism economy: The case of Portuguese overseas investment in the hotel sector

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    Doutoramento em TurismoO presente trabalho de investigação analisa a importância das redes formais e informais na internacionalização da economia do turismo, em particular do sector hoteleiro. Para tal baseia-se numa extensa revisão bibliográfica sobre as teorias que explicam o investimento directo no estrangeiro, assim como a abordagem das redes aplicada à internacionalização e o seu enquadramento no sector do turismo. Com base na revisão de literatura, uma série de hipóteses são sugeridas, as quais são testadas na parte empírica da tese através de uma análise às empresas Portuguesas com investimentos no estrangeiro na área da hotelaria até ao final de 2007 ou com projectos em curso. Esta análise baseia-se principalmente em dados obtidos através de entrevistas-questionário realizadas aos responsáveis das empresas. O inquérito obteve 40% de taxa de resposta, contendo dados relativos às características das empresas e de cada um dos projectos realizados no estrangeiro. Com base nestes resultados são sugeridas uma série de implicações, assim como algumas recomendações para investigações futuras. Adicionalmente, e de forma a investigar mercados com diferentes realidades sócio-culturais, políticas e cultura de negócios, foi analisado o caso de Goa, através de trabalho de campo que envolveu entrevistas informais e semiestruturadas a entidades-chave ligadas ao sector do turismo e aos hoteleiros de unidades de qualidade média-alta. Foi identificado um conjunto de oportunidades e desafios para as empresas Portuguesas. Ao usar uma abordagem qualitativa e quantitativa, esta tese contribui para a compreensão da natureza, determinantes e dimensões do processo de internacionalização do sector do turismo.This thesis examines the importance of formal and informal networks in the internationalisation of the tourism economy, particularly the hotel sector. For this purpose, the study is based on an extensive literature review on the theories that explain foreign direct investment as well as the network approach applied to the internationalisation process and to the tourism sector. Based on the literature review, a number of hypotheses are suggested, which are tested in the empirical part of the thesis through an analysis of the Portuguese companies with investments abroad in the hotel sector. The population studied consisted of Portuguese companies that possessed/managed at least one hotel establishment abroad until the end of 2007 or companies that were starting their internationalisation process in the hotel sector. This analysis is based mainly on data obtained through interviewquestionnaires aimed at chief executives of each company. The survey obtained 40 percent response rate, containing data on the characteristics of the companies and of each project abroad. Based on these results a number of implications are suggested, as well as some recommendations for future research. Additionally, in order to investigate psychic distant markets, it was examined the case of Goa, through fieldwork research that involved informal and semistructured interviews to key stakeholders in the tourism sector and to managers/owners of medium-range and upscale hotels. A number of opportunities and challenges for Portuguese companies were then identified. Using both qualitative and quantitative approaches, this thesis aimed at contributing to a better understanding of the nature, determinants and dimensions of internationalisation in the tourism sector

    Department of Defense Dictionary of Military and Associated Terms

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    The Joint Publication 1-02, Department of Defense Dictionary of Military and Associated Terms sets forth standard US military and associated terminology to encompass the joint activity of the Armed Forces of the United States. These military and associated terms, together with their definitions, constitute approved Department of Defense (DOD) terminology for general use by all DOD components

    Aeronautical engineering: A cumulative index to a continuing bibliography (supplement 235)

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    This publication is a cummulative index to the abstracts contained in Supplements 223 through 234 of Aeronautical Engineering: A Continuing Bibliography. The bibliographic series is compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). Seven indexes are included -- subject, personal author, corporate source, foreign technology, contract number, report number and accession number

    Rollins College Catalog 1990-1991

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