959 resultados para Light rail vehicles.
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The large eyes and well-developed visual system of billfishes suggest that vision is an important sense for the detection and interception of prey and lures. Investigations of visual abilities in these large pelagic fishes are difficult, however anatomical studies of billfish eyes and retinas allow prediction of a number of visual capabilities. From the density of ganglion cells in the blue marlin (Makaira nigricans) retina, visual acuities of less than 10 cycles per degree were derived, a surprisingly low visual resolution given the absolute size of the marlin eye. Cone photoreceptors, on the other hand, were present in high densities, resulting in a presumed summation of cones to ganglion cells at a ratio of 40:1, even in the area of best vision. The optical sensitivity of the marlin eye was high owing to the large dimensions of the cone photoreceptors. These results indicate that the marlin eye is specifically adapted to cope with the low light levels encountered during diving. Since the marlin is likely to use its vision at depth, it is suggested that this line of research could help estimate the limits of vertical distribution based on light level.
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In the previous two papers in this three-part series, we have examined visual pigments, ocular media transmission, and colors of the coral reef fish of Hawaii. This paper first details aspects of the light field and background colors at the microhabitat level on Hawaiian reefs and does so from the perspective and scale of fish living on the reef. Second, information from all three papers is combined in an attempt to examine trends in the visual ecology of reef inhabitants. Our goal is to begin to see fish the way they appear to other fish. Observations resulting from the combination of results in all three papers include the following. Yellow and blue colors on their own are strikingly well matched to backgrounds on the reef such as coral and bodies of horizontally viewed water. These colors, therefore, depending on context, may be important in camouflage as well as conspicuousness. The spectral characteristics of fish colors are correlated to the known spectral sensitivities in reef fish single cones and are tuned for maximum signal reliability when viewed against known backgrounds. The optimal positions of spectral sensitivity in a modeled dichromatic visual system are generally close to the sensitivities known for reef fish. Models also predict that both UV-sensitive and red-sensitive cone types are advantageous for a variety of tasks. UV-sensitive cones are known in some reef fish, red-sensitive cones have yet to be found. Labroid colors, which appear green or blue to us, may he matched to the far-red component of chlorophyll reflectance for camouflage. Red cave/hole dwelling reef fish are relatively poorly matched to the background they are often viewed against but this may be visually irrelevant. The model predicts that the task of distinguishing green algae from coral is optimized with a relatively long wavelength visual pigment pair. Herbivorous grazers whose visual pigments are known possess the longest sensitivities so far found. Labroid complex colors are highly contrasting complementary colors close up but combine, because of the spatial addition, which results from low visual resolution, at distance, to match background water colors remarkably well. Therefore, they are effective for simultaneous communication and camouflage.
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Conventional kinesin is a microtubule-based molecular motor involved in the transport of membranous and non-membranous cargoes. The kinesin holoenzyme exists as a heterotetramer, consisting of two heavy chain and two light chain subunits. It is thought that one function of the light chains is to interact with the cargo. Alternative splicing of kinesin light chain pre-mRNA has been observed in lower organisms, although evidence for alternative splicing of the human gene has not been reported. We have identified 19 variants of the human KNS2 gene (KLC1) that are generated by alternative splicing of downstream exons, but calculate that KNS2 has the potential to produce 285919 spliceforms. Corresponding spliceforms of the mouse KLC1 gene were also identified. The alternative exons are all located 3' of exon 12 and the novel spliceforms produce both alternative carboxy termini and alternative 3' untranslated regions. The observation of multiple light chain isoforms is consistent with their proposed role in specific cargo attachment.
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This study was carried out to investigate the effects of light spectra, additional UV-A, and different growth regulators on the in vitro germination of Senecio cineraria DC. Seeds were surface-sterilized and inoculated in MS medium to evaluate the following light spectra: white, white plus UV-A, blue, green, red or darkness. The maximum germinability was obtained using MS0 medium under white light (30%) and MS + 0.3 mg L-1 GA3 in the absence of light (30.5%). S. cineraria seeds were indifferent to light. Blue and green lights inhibited germination. Different concentrations of gibberellic acid (GA3) (0.1; 0.4; 0.6; 0.8; 1.0 and 2.0 mg L-1) and indole-3-acetic acid IAA (0.1; 0.3 and 1.0 mg L-1) were evaluated under white light and darkness. No concentration of GA3 enhanced seed germination percentage under white light. However, when the seeds were maintained in darkness, GA3 improved germination responses in all tested concentrations, except at 1.0 mg L-1. Under white light, these concentrations also increased the germination time and reduced germination rate. Germination rate, under light or darkness, was lower using IAA compared with GA3.
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Resumo: 1 – Sumário do Acórdão do Supremo Tribunal de Justiça, de 13 de Abril de 2011; 2 – Texto completo do Acórdão do Supremo Tribunal de Justiça, de 13 de Abril de 2009, Juiz Conselheiro Rodrigues da COSTA (Relator), Juiz Conselheiro Arménio SOTTOMAYOR (vencido nos termos da declaração junta) e Juiz Conselheiro Mota MIRANDA: cfr. http://www.dgsi.pt , 26 de Abril de 2011; 3 – Anotação; 3.1 – Introdução à anotação; 3.2 – A questão do suposto «bem jurídico» que seria tutelado pelo crime de «lenocínio» p.p.p.p.p. 169.º do código penal português; 3.2.1 – Ainda a questão do suposto «bem jurídico» que seria tutelado pelo crime de «lenocínio» p.p.p.p.p. 169.º do código penal português: uma maior procura e concretização jurídica e científica; 4 – Conclusões; § Abstract: 1 - Summary of the Sentence of the Supreme Court of Justice, 13 of April of 2011; 2 - Complete text of the Sentence of the Supreme Court of Justice, 13 of April of 2009, Advising Judge Rodrigues da COSTA (Reporter), Advising Judge Arménio SOTTOMAYOR (looser in the terms of the together declaration) and Advising Judge Mota MIRANDA: cfr. http://www.dgsi.pt , 26 of April of 2011; 3 - Notation; 3.1 - Introduction to the notation; 3.2 - The question of the presumption «legally protected interest» that would be tutored person for the crime of «pimpery (“pimping”)» p.p.p.p.p. 169.º of the Portuguese criminal code; 3.2.1 - Still the question of the presumption «legally protected interest» that would be tutored person for the crime of «pimpery» («pimping») p.p.p.p.p. 169.º of the Portuguese criminal code: a bigger search and legal and scientific concretion; 4 - Conclusions;
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The silvopastoral system is a viable technological alternative to extensive cattle grazing, however, for it to be successful, forage grass genotypes adapted to reduced light need to be identified. The objective of this study was to select progenies of Panicum maximum tolerant to low light conditions for use in breeding programs and to study the genetic control and performance of some traits associated with shade tolerance. Six full-sib progenies were evaluated in full sun, 50% and 70% of light reduction in pots and subjected to cuttings. Progeny genotypic values (GV) increased with light reduction in relation to plant height (H) and specific leaf area (SLA). The traits total dry mass accumulation (DM) and leaf dry mass accumulation (LDM) had GV higher in 50% shade and intermediate in 70% shade. The GV of tiller number (TIL) and root dry mass accumulation (RDM) decreased with light reduction. The highest positive correlations were obtained for the traits H and RDM with SLA and DM; the highest negative correlations were between TIL and SLA and RDM, and H and LDM. The progenies showed higher tolerance to 50% light reduction and, among them, two stood out and will be used in breeding programs. It was also found that it is not necessary to evaluate some traits under all light conditions. All traits had high broad sense heritability and high genotypic correlation between progenies in all light intensities. There is genetic difference among the progenies regarding the response to different light intensities, which will allow selection for shade tolerance
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In this paper we present an amorphous silicon device that can be used in two operation modes to measure the concentration of ions in solution. While crystalline devices present a higher sensitivity, their amorphous counterpart present a much lower fabrication cost, thus enabling the production of cheap disposable sensors for use, for example, in the food industry. The devices were fabricated on glass substrates by the PECVD technique in the top gate configuration, where the metallic gate is replaced by an electrolytic solution with an immersed Ag/AgCl reference electrode. Silicon nitride is used as gate dielectric enhancing the sensitivity and passivation layer used to avoid leakage and electrochemical reactions. In this article we report on the semiconductor unit, showing that the device can be operated in a light-assisted mode, where changes in the pH produce changes on the measured ac photocurrent. In alternative the device can be operated as a conventional ion selective field effect device where changes in the pH induce changes in the transistor's threshold voltage.
Design of improved rail-to-rail low-distortion and low-stress switches in advanced CMOS technologies
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This paper describes the efficient design of an improved and dedicated switched-capacitor (SC) circuit capable of linearizing CMOS switches to allow SC circuits to reach low distortion levels. The described circuit (SC linearization control circuit, SLC) has the advantage over conventional clock-bootstrapping circuits of exhibiting low-stress, since large gate voltages are avoided. This paper presents exhaustive corner simulation results of a SC sample-and-hold (S/H) circuit which employs the proposed and optimized circuits, together with the experimental evaluation of a complete 10-bit ADC utilizing the referred S/H circuit. These results show that the SLC circuits can reduce distortion and increase dynamic linearity above 12 bits for wide input signal bandwidths.
Análise dos métodos de medição dos parâmetros geométricos de via e correlação entre os dados obtidos
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A razão atribuída à escolha do tema do T.F.M. em Caminhos-de-ferro, tem a ver com o facto de ser uma via de comunicação específica. Contrariamente ao que acontece na execução de auto-estradas, no caminho-de-ferro, a gestora da infra-estrutura responsabiliza-se pela execução, exploração (sinalização e controlo de circulação), abastecimento de energia fornecida às vias que dispõem de catenária (tracção eléctrica), manutenção e conservação da via. O processo de análise e inspecção de geometria de via, é usado quando e necessário preservar a infra-estrutura. Este processo iniciou-se nos caminhos-de-ferro portugueses, há muitos anos, depois da inauguração do primeiro troco de linha férrea. A primeira viagem ocorre em Outubro de 1856, sendo o início do processo em 1968, com a dresina “Matisa PV-6”. Em 1991 a C.P. adquiriu outro veículo de inspecção de via, tendo sido escolhido o VIV02 EM 120 da marca Plasser & Theurer, para substituir “Matisa PV-6”. O tema Análise dos Métodos de Medição dos Parâmetros Geométricos de Via e Correlação entre os Dados Obtidos está directamente relacionado com a manutenção e conservação de via. Na Unidade Operacional Sul (hoje ROS – Região Operacional Sul), local onde desenvolvi o T.F.M., não existem obras de construção de caminhos-de-ferro que pudesse acompanhar e constituir tema para o meu trabalho. Na realidade, com a falta de investimento que se perspectiva no futuro próximo, a manutenção da infra-estrutura passa a ser a actividade principal desenvolvida pela REFER, de modo a assegurar a comodidade, segurança e rapidez na deslocação de cargas e pessoas. A Analise Geométrica de Via e actualmente uma das principais actividades no âmbito da manutenção, que é feita por diagnóstico, contrariamente ao que acontecia no passado em que a conservação metódica era realizada num determinado ano num troço seleccionado independentemente da necessidade ou não da mesma. Uma ajuda preciosa, no que se refere à decisão de se realizar um determinado trabalho de conservação, e a do veículo VIV02 EM 120 que faz inspeções ao longo de toda a rede ferroviária e permite recolher dados e classificar através do desvio padrão, troços com extensão de 200 metros, obtendo os dados relevantes sobre a necessidade de intervenção. Para além do referido veículo existem também equipamentos ligeiros de inspecção dos parâmetros geométricos de via. Um desses equipamentos designa-se por Trólei, não sendo motorizado, pois o mesmo é movido manualmente por um operador. Obviamente que este equipamento não faz a inspecção a toda a rede pois a operação de medição é morosa, sendo contudo utilizado para análise de defeitos geométricos em pequenos trocos, tornando-se assim uma mais-valia, evitando o deslocar de um equipamento “pesado” como o VIV 02 EM 120. Para atingir os objectivos deste trabalho realizaram-se testes de medição com ambos (veiculo e equipamento ligeiro), no mesmo espaço temporal e com as mesmas características físicas, como a temperatura, humidade etc. Os resultados, de acordo com os objectivos, são a comparação entre as medições de ambos, com vista a comprovar a sua utilidade e necessidade, de acordo com os vários tipos de superstruturas constituintes da rede ferroviária nacional.
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A maioria das infra-estruturas de transportes, nomeadamente os pavimentos rodoviários e aeroportuários, são constituídas por misturas betuminosas, o que permite um bom desempenho e uma adequada durabilidade, nas condições usuais de serviço. As misturas betuminosas são ainda amplamente utilizadas na construção de zonas de estacionamento de veículos, tendo-se verificado recentemente a sua aplicação também em infra-estruturas ferroviárias. Face à necessidade de melhorar o desempenho das vias-férreas, permitindo uma concepção mais durável de linhas de alta velocidade e uma redução dos custos da sua manutenção, tem-se vindo a desenvolver diversos estudos para promover a utilização de novos materiais, principalmente através da incorporação de misturas betuminosas. O presente trabalho tem como objectivo a caracterização do comportamento mecânico de misturas betuminosas a aplicar em infra-estruturas de transportes. Como metodologia para o estudo do comportamento mecânico das misturas betuminosas foram realizados em laboratório ensaios de cargas repetidas, nomeadamente, ensaios de flexão em quatro pontos para determinação da rigidez e da resistência à fadiga e ensaios de compressão triaxiais cíclicos para avaliação do comportamento à deformação permanente. A resistência à fadiga das misturas betuminosas em estudo foi avaliada através do ensaio de flexão em quatro pontos, com extensão controlada, e aplicação de um carregamento sinusoidal com diferentes frequências, de acordo com o procedimento de ensaio da norma europeia EN 12697-24 (2004 + A1: 2007). A resistência à deformação permanente das misturas betuminosas foi analisada através de ensaios de compressão triaxiais cíclicos, submetendo-as a uma tensão de confinamento estática pela aplicação parcial de vácuo e a uma pressão axial cíclica sob a forma rectangular, de acordo com a norma europeia EN 12697-25 (2004). O conhecimento destas propriedades mecânicas assume particular importância ao nível da formulação das misturas betuminosas, do dimensionamento de uma estrutura ou do estabelecimento de uma adequada solução para uma obra de reabilitação duma infra-estrutura de transportes. Para este estudo foi utilizado um modelo físico construído numa fossa no LNEC, com o propósito de serem testadas três substruturas ferroviárias não convencionais, utilizando sub-balastro betuminoso. A selecção das substruturas foi efectuada após uma análise de várias secções de estruturas já testadas e aplicadas noutros países, de forma a proporcionar comparações fiáveis entre elas. Os resultados obtidos mostraram que a mistura betuminosa AC20 base 50/70 (MB) aplicada na camada de sub-balastro é adequada para ser aplicada nas infra-estruturas de transportes pois apresenta um bom desempenho à fadiga e à deformação permanente. Através dos ensaios efectuados foi ainda possível entender a importante influência das características volumétricas, principalmente da porosidade para o bom comportamento da mistura betuminosa.
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Since industrialization and the formation of larger urban centers in the nineteenth century, pollution of the environment was always present in daily life in various ways, namely in the form of light. Light pollution can cause various consequences, both for humans and for their ecosystem, producing effects on environmental, social, economic and scientific level. In Portugal, the lighting is responsible for 3% of total electricity consumption, energy costs are in some cases more than 50% towards the costs incurred by municipalities with energy, checking-in recent years a trend similar to that improvement of illumination levels in the region (about 4 to 5% per year). Proper use of lighting brings many benefits both to the citizen and environment, since greater energy efficiency can contribute to reducing CO2 emissions, energy costs, as well as to decrease the use of resources not-renewable and/or contamination of renewable resources, which can occurs in the process of obtaining electricity. The present study has a main goal to analyze the illuminance levels associated to the public lighting of the village of Vialonga, Vila Franca de Xira (Portugal), to verify if it is efficient. The aim is also to relate the efficiency of street lighting with the existence of light pollution.
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We study the implications of the searches based on H -> tau(+)tau-by the ATLAS and CMS collaborations on the parameter space of the two-Higgs-doublet model (2HDM). In the 2HDM, the scalars can decay into a tau pair with a branching ratio larger than the SM one, leading to constraints on the 2HDM parameter space. We show that in model II, values of tan beta > 1.8 are definitively excluded if the pseudoscalar is in the mass range 110 GeV < m(A) < 145 GeV. We have also discussed the implications for the 2HDM of the recent dimuon search by the ATLAS collaboration for a CP-odd scalar in the mass range 4-12 GeV.
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In this work it is proposed the design of a mobile system to assist car drivers in a smart city environment oriented to the upcoming reality of Electric Vehicles (EV). Taking into account the new reality of smart cites, EV introduction, Smart Grids (SG), Electrical Markets (EM), with deregulation of electricity production and use, drivers will need more information for decision and mobility purposes. A mobile application to recommend useful related information will help drivers to deal with this new reality, giving guidance towards traffic, batteries charging process, and city mobility infrastructures (e. g. public transportation information, parking places availability and car & bike sharing systems). Since this is an upcoming reality with possible process changes, development must be based on agile process approaches (Web services).
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The large penetration of intermittent resources, such as solar and wind generation, involves the use of storage systems in order to improve power system operation. Electric Vehicles (EVs) with gridable capability (V2G) can operate as a means for storing energy. This paper proposes an algorithm to be included in a SCADA (Supervisory Control and Data Acquisition) system, which performs an intelligent management of three types of consumers: domestic, commercial and industrial, that includes the joint management of loads and the charge/discharge of EVs batteries. The proposed methodology has been implemented in a SCADA system developed by the authors of this paper – the SCADA House Intelligent Management (SHIM). Any event in the system, such as a Demand Response (DR) event, triggers the use of an optimization algorithm that performs the optimal energy resources scheduling (including loads and EVs), taking into account the priorities of each load defined by the installation users. A case study considering a specific consumer with several loads and EVs is presented in this paper.