496 resultados para Rotatory Inertia
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In the past two decades the History of Construction has started to become an independent discipline. On one hand, the number of articles, theses and books that could be assigned to this field has grown exponentially. Furthermore, there have been numerous and remarkably successful Congresses: 12 National (Spain 8; France 2; United Kingdom 1; Germany 1) and 4 International Congresses (Madrid 2003, Cambridge 2006, Cottbus 2009, Paris 2012), see Table 1 below. However, the situation is far from that corresponding to an already recognized discipline, such as the History of Art or the History of Science. There are no University chairs and departments, and in the reference databases “Construction History” is not listed as a common descriptor. This is not surprising; it reflects the inertia of academia to accept new disciplines. In what follows we will discuss the current state of discipline in Spain. Previous articles have tackled the matter. We will try to avoid unnecessary repetitions and concentrate on: 1) The activities of the Spanish Society of Construction History; 2) Its consequences on teaching and research, taken as a case study the experience in the School of Architecture of Madrid, and 3) We will give a provisional List of dissertations on Construction History read in Spain in the last forty years. First, we will try to define with the least possible ambiguity its field and its objectives. The intention is not to enter into the actual debate on the "definition" of Construction History, but to expose, in as detached as possible way, the ideas behind the actions made.
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Ao longo dos últimos trinta anos, entre meados das décadas de 1980 e 2010, os sistemas de saúde da Alemanha, França e Reino Unido foram reformados, gerando uma crescente mercantilização no financiamento e na prestação de serviços. O trabalho analisa as raízes dessas mudanças, assim como identifica que a mercantilização não ocorreu nem mediante os mesmos mecanismos e nem com a mesma profundidade, havendo importante inércia institucional. As diferenças observadas atestam as especificidades de cada país, em termos de seu contexto econômico, de seus arranjos políticos, das características institucionais de cada sistema e das formas que assumiram os conflitos sociais (extra e intra sistema de saúde). Os sistemas de saúde alemão, francês e britânico, enquanto sistemas públicos de ampla cobertura e integralidade, são frutos do período após a Segunda Guerra Mundial. Um conjunto de fatores contribuiu para aquele momento histórico: os próprios impactos do conflito, que forjaram a ampliação na solidariedade nacional e a maior pressão por parte dos trabalhadores; a ascensão socialista na União Soviética; o maior apoio à ação e ao planejamento estatal; o forte crescimento econômico, fruto da emersão de um regime de acumulação fordista, pautado na expansão da produtividade. A acomodação do conflito capital-trabalho, neste contexto, ocorreu mediante a expansão dos salários reais e ao desenvolvimento do Estado de bem-estar social, ou seja, de políticas públicas voltadas à criação e/ou ampliação de uma rede de proteção social. No entanto, a crise econômica da década de 1970 corroeu a base de financiamento e gerou questionamentos sobre sua eficiência, em meio à transformação do regime de acumulação de fordista para financeirizado, levando à adoção de reformas constantes ao longo das décadas seguintes. Além disso, as transformações específicas do setor saúde complexificaram a situação, tendo em vista o crescente envelhecimento populacional, a demanda por cuidados mais amplos e complexos e, principalmente, os custos derivados da incorporação tecnológica. Este cenário impulsionou a implementação de uma série de alterações nesses sistemas de saúde, com destaque para a incorporação de mecanismos de mercado (como a precificação dos serviços prestados, a indução à concorrência entre prestadores de serviços), o crescimento da responsabilidade dos usuários pelo financiamento do sistema (como o aumento nos co-pagamentos e a redução na cobertura pública) e a ampliação da participação direta do setor privado na prestação dos serviços de saúde (realizando os serviços auxiliares, a gestão de hospitais públicos, comprando instituições estatais). No entanto, de forma simultânea, as reformas ampliaram o acesso e a regulamentação estatal, além da modificação na base de financiamento, principalmente na França. Isto significa que a mercantilização não foi o único direcionamento das reformas, em decorrência de dois fatores principais: a própria crise econômica expulsou parcela da população dos mecanismos pós-guerra de proteção à saúde, demandando reação estatal, e diferentes agentes sociais influenciaram nas mudanças, bloqueando ou ao menos limitando um direcionamento mercantil único.
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O fenômeno de vibração induzida por vórtices (VIV) é um problema fundamental dentro da Mecânica dos Fluidos e um exemplo importante de interação fluido-estrutura. Esta tese investiga fenômeno de VIV quando um cilindro rígido, submetido a escoamento uniforme, está livre para oscilar na direção transversal e alinhada com a corrente incidente. A tese foi estruturada ao redor de sete perguntas relacionadas ao fenômeno de VIV: 1) O fenômeno e os resultados experimentais são repetitivos? 2) Como ocorre a transição entre ramos de resposta? 3) Qual é o papel da inércia da estrutura oscilante? 4) Qual é o papel de sua rigidez? 5) Quais são as frequências naturais mais importantes da estrutura? 6) Quais padrões de esteira se desenvolvem para VIV com dois graus de liberdade? 7) Quais são os efeitos do movimento na direção alinhada com a corrente no processo de formação e desprendimento de vórtices? O fenômeno de VIV é estudado de maneira experimental em uma base elástica pendular capaz de oscilar com o mesmo momento de inércia e frequência natural nas duas direções. Os experimentos de VIV foram realizados em canal de água recirculante e com diferentes condições de inércia e rigidez. A técnica de velocimetria por imagem de partículas foi usada e permitiu identificar diferentes padrões de esteira de vórtices. Verificou-se que o VIV é repetitivo a nível de amplitudes médias e frequências dominantes. A transição dos ramos pode ocorrer de maneira intermitente ou com histerese. Os parâmetros de inércia e rigidez da estrutura são capazes de mudar o regime de oscilação e, para algumas condições, suprimir as vibrações alinhadas com a corrente. Dentre os padrões de esteira observados, um deles não havia sido relatado na literatura e é definido nesta tese. O novo modo de emissão apresenta dois vórtices com circulação oposta e elevada intensidade emitidos por ciclo. A influência da direção alinhada com o escoamento está relacionada a dois efeitos: a velocidade relativa entre o cilindro e o fluido, responsável pelo aumento da circulação dos vórtices na esteira, e o ângulo de fase do movimento nas direções alinhada e transversal, capaz de mudar o processo de formação dos vórtices.
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Excavated towns are an attractive example of underground urbanism that managed to solve, in a very interesting way, thermal problems thanks to natural ground inertia or transition spaces. The aim of this paper is to show the typological evolution of excavated dwellings worldwide, as an architectural proposal and urban solution. The proposed methodology provides an analysis of underground architectures from natural caves to excavated housing, focusing on the study of global constructive solutions to specific problems. Thus, architectures as a natural geography correction (horizontal excavation), buried underground architectures (vertical excavation), subtractive architectures (shallow excavation) and combined architectures (mixed excavation) are studied. In conclusion, there are many examples of typological combinations since troglodyte architects tried to adapt the most elementary constructive rules to get greatly enriched results. These proposals of different underground structures deal with each territory and its geographical features, and obtain urban and architectural solutions transferable to current configurations.
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Underground architecture has sheltered man for many centuries, but the current need to emphasize the bioclimatic approach makes the study of excavated housing essential. This traditional construction is a part of the collective human living experience but also a reference in using the natural conditions of each region through simple proposals based on ground thermal inertia. The aim of this paper is to show the typological evolution of the excavated dwelling in Crevillente, in southeast Spain, compared to other worldwide architectural proposals or urban solutions. To show their adaptation to the regional geography and to comprehend both formal and material characteristics of these simple typologies, which do not need extra energy contribution for interior conditioning. This work is part of the doctoral thesis of the author.
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We consider the simplest relevant problem in the foaming of molten plastics, the growth of a single bubble in a sea of highly viscous Newtonian fluid, and without interference from other bubbles. This simplest problem has defied accurate solution from first principles. Despite plenty of research on foaming, classical approaches from first principles have neglected the temperature rise in the surrounding fluid, and we find that this oversimplification greatly accelerates bubble growth prediction. We use a transport phenomena approach to analyze the growth of a solitary bubble, expanding under its own pressure. We consider a bubble of ideal gas growing without the accelerating contribution from mass transfer into the bubble. We explore the roles of viscous forces, fluid inertia, and viscous dissipation. We find that bubble growth depends upon the nucleus radius and nucleus pressure. We begin with a detailed examination of the classical approaches (thermodynamics without viscous heating). Our failure to fit experimental data with these classical approaches, sets up the second part of our paper, a novel exploration of the essential decelerating role of viscous heating. We explore both isothermal and adiabatic bubble expansion, and also the decelerating role of surface tension. The adiabatic analysis accounts for the slight deceleration due to the cooling of the expanding gas, which depends on gas polyatomicity. We also explore the pressure profile, and the components of the extra stress tensor, in the fluid surrounding the growing bubble. These stresses can eventually be frozen into foamed plastics. We find that our new theory compares well with measured bubble behavior.
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Tese de mestrado integrado em Engenharia da Energia e do Ambiente, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2016
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The purpose of this paper is to analyse the economic basis of mass support for, and opposition to the European Community. In other words the main question is: to what extent, and in what ways, is popular support or opposition to the EC dependent upon economic circumstances and considerations? Behind this research question lies the matter of the legitimacy of the EC in the eyes of citizens across Europe. In some respects the results of this study are frustrating and inconclusive. In other respects, however, the results suggest some clear generalizations and conclusions. First, we have found rather little evidence that the EC or European unification are evaluated in primarily economic terms. Secondly, support seems to be associated more strongly with social and attitudinal variables of a non-economic kind. Thirdly, the figures suggest that diffuse and somewhat idealistic reasons for supporting unification and EC membership tend to outweigh more specific reasons. Fourthly, a solid foundation of inertia, custom, and national tradition seem to maintain support and make it grow.
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The true causes of the EU’s inertia as a security actor in its neighbourhood and beyond are not a lack of capability or even austerity measures, but the absence of a core group of states committed to driving integration forward, argues Giovanni Faleg. Member states are reluctant to set clear common strategic priorities and struggle to agree on a revision of the institutional rules. Their strategic cultures and interests differ significantly; they hold different visions of the Common Security and Defence Policy (CSDP) and are unwilling to use the CSDP instruments at their disposal.
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EDITED VERSION SOON TO BE PUBLISHED In this paper the effect of decoupling on the capitalisation of agricultural subsidies into agricultural rents in Ireland are analysed using a dynamic rental equations estimated with a two step system GMM estimator that accounts for expectation error and endogenous regressors. The findings illustrate the importance of institutional details in determining the extent to which subsidies are capitalised. In the period prior to decoupling Pillar 1 subsidies were highly capitalised into Irish agricultural rents in both the short and the long run. Depending on the farm system considered between 58 to 80 cents per euro of subsidies were capitalised into agricultural rents. In the post decoupling period the rate at which Pillar 1 subsidies are capitalised into Irish agricultural rents is found to have declined. This change is likely due to short term character of the Irish agricultural land rental market, where 11 month rental periods predominate, and the freedom that the 2003 reform of the CAP offered farmers to consolidate entitlements established on rented land. The generally very short term nature of Irish agricultural rental contracts offered farmers an opportunity to consolidate entitlements that is unlikely to have arisen in other Member States with agricultural land rental markets characterised by long term contracts. The results in both the pre and post decoupling periods highlight the high degree of inertia of agricultural rents in Ireland, and the importance of accounting for dynamics when investigating the capitalisation of agricultural subsidies into land rents. The high degree of inertia in rents means that the impact of previously capitalised agricultural policy persists through time.
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This essay will show that the Schröder-led government managed to break the political gridlock and introduce the Agenda 2010 because key institutional structures of Germany‟s political economy had lost their obstructive powers. In other words, the formerly semi-sovereign state had reclaimed its sovereignty. To understand how this happened, Peter Katzenstein's concept of the semi-sovereign state is first explored as a framework through which to analyze economic policy continuity and change. Within this framework, the causes for constant reform inertia between 1982 and 2002, in spite of varying political constellations and changes in the country‟s economic structure, are then discussed. This analysis will demonstrate that the Agenda 2010 reforms are predominantly a result of underlying incremental change in the political economy and its effect on the political decision-making process. Finally, the findings of this analysis are summarized and discussed with the aim of better understanding the economic policies of the current grand coalition government of the CDU/CSU and the SPD government under Chancellor Angela Merkel.
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EXECUTIVE SUMMARY All observers agree that energy efficiency must be the cornerstone of any serious EU energy strategy. In this general context, the EU building sector is critical. It represents about 40% of EU final energy consumption (residential houses, public/private offices, commercial buildings, etc.) and approximately 36% of EU CO2 emissions. This is massive. The EU has certainly not been inactive in this field. The Energy Performance in Buildings Directive 2002/91/EC (EPBD) was the first and the main instrument to address the problem of the energy performance of buildings. It has established numerous principles: a reliable methodology which enables the calculation and rating of the energy performance of buildings; minimum energy performance standards for new buildings and existing buildings under major renovation; energy performance certificates; regular inspection of heating and air-conditioning systems; and, finally, quality standards for inspections and energy performance certificates. They were strengthened in 2010 by the recast Directive 2010/31/EU. This directive also introduces a decisive concept for the development of the building sector: ‘nearly zeroenergy buildings’. In 2012, the new Energy Efficiency Directive 2012/27/EU dealt with other aspects. In the building sector, three of them are particularly important. They concern: (1) the establishment of long-term strategies for mobilizing investment in the renovation of the national building stocks; (2) the introduction of energy saving schemes for ‘designated’ energy companies with a view to reducing consumption among ‘final consumers’ by 1.5% annually; and (3), as an option, the setting up of an Energy Efficiency National Fund to support energy efficiency initiatives. This paper also briefly examines the different instruments put in place to disseminate information and consultation, and the EU funding for energy efficiency in buildings. Results, however, have remained limited until now. The improvement of the energy performance of buildings and the rhythm of renovation remain extremely weak. Member States’ unwillingness to timely and properly transpose and implement the Directives continues despite the high degree of flexibility permitted. The decentralized approach chosen for some specific aspects and the differentiation in the application of EPBD standards between Member States do not appear optimal either. Adequate financial schemes remain rare. The permanent deficit of qualified and trained personnel and the inertia of public authorities to make the public understand the stakes in this domain remain problematic. Hence the need to take new initiatives to reap the benefits that the building sector is meant to bring.
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Todos os anos milhares de hectares são consumidos pelas chamas durante a época de incêndios. As medidas preventivas têm-se revelado insuficientes e as capacidades dos meios de combate estão condicionadas por terrenos inacessíveis, condições de visibilidade reduzida e condições meteorológicas adversas. Com a introdução do projéctil projectado nesta dissertação pretende-se preencher de algum modo o vazio deixado por essas condicionantes. Este projecto dá continuidade ao projecto FIREND® que é a última evolução de um conceito idealizado em 2005 e que se tem vindo a desenvolver numa parceria entre a Academia Militar e o Instituto Superior técnico. O conhecimento assimilado pela revisão bibliográfica de algumas patentes, dos projectos FIREND® anteriores e sobre o funcionamento de projécteis de artilharia convencionais, foi complementada com os conhecimentos de balística e de projecto mecânico, resultando no desenvolvimento sólido de um projéctil de 155mm de detonação electrónica. O projéctil funciona com base num micro gerador de gás que aumenta a pressão interior e desta forma ejecta a carga contida no compartimento de carga. Foram utilizadas as capacidades de desenho tridimensional do software SolidWorks® e estimou-se, através deste, o peso, volume, momentos de inércia dos componentes e a capacidade de carga do projéctil. Estes dados são fundamentais neste projecto para garantir a sua compatibilidade com os obuses e tábuas de tiro utilizadas pela Artilharia do Exército Português. Como resultado, projectou-se um projéctil de 155mm com peso equivalente ao de uma granada convencional e com cotas máximas que lhe conferem total compatibilidade com os Obuses de Artilharia existentes. O projéctil consegue conter, no seu compartimento de carga, aproximadamente 7,5 dm3 de volume, o que lhe confere a capacidade para actuar numa área de aproximadamente 75m2.
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Due to extensive clinical and electrophysiological overlaps, the correct diagnosis of disorders with excessive daytime sleepiness is often challenging. The aim of this study was to provide diagnostic measures that help discriminating such disorders, and to identify parameters, which don't. In this single-center study, we retrospectively identified consecutive treatment-naïve patients who suffered from excessive daytime sleepiness, and analyzed clinical and electrophysiological measures in those patients in whom a doubtless final diagnosis could be made. Of 588 patients, 287 reported subjective excessive daytime sleepiness. Obstructive sleep apnea is the only disorder that could be identified by polysomnography alone. The diagnosis of insufficient sleep syndrome relies on actigraphy as patients underestimate their sleep need and the disorder shares several clinical and electrophysiological properties with both narcolepsy type 1 and idiopathic hypersomnia. Sleep stage sequencing on MSLT appears helpful to discriminate between insufficient sleep syndrome and narcolepsy. Sleep inertia is a strong indicator for idiopathic hypersomnia. There are no distinctive electrophysiological findings for the diagnosis of restless legs syndrome. Altogether, EDS disorders are common in neurological sleep laboratories, but usually cannot be diagnosed based on PSG and MSLT findings alone. The diagnostic value of actigraphy recordings can hardly be overestimated.
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National Highway Traffic Safety Administration, Washington, D.C.