853 resultados para Trains -- Sri Lanka
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Three types of forecasts of the total Australian production of macadamia nuts (t nut-in-shell) have been produced early each year since 2001. The first is a long-term forecast, based on the expected production from the tree census data held by the Australian Macadamia Society, suitably scaled up for missing data and assumed new plantings each year. These long-term forecasts range out to 10 years in the future, and form a basis for industry and market planning. Secondly, a statistical adjustment (termed the climate-adjusted forecast) is made annually for the coming crop. As the name suggests, climatic influences are the dominant factors in this adjustment process, however, other terms such as bienniality of bearing, prices and orchard aging are also incorporated. Thirdly, industry personnel are surveyed early each year, with their estimates integrated into a growers and pest-scouts forecast. Initially conducted on a 'whole-country' basis, these models are now constructed separately for the six main production regions of Australia, with these being combined for national totals. Ensembles or suites of step-forward regression models using biologically-relevant variables have been the major statistical method adopted, however, developing methodologies such as nearest-neighbour techniques, general additive models and random forests are continually being evaluated in parallel. The overall error rates average 14% for the climate forecasts, and 12% for the growers' forecasts. These compare with 7.8% for USDA almond forecasts (based on extensive early-crop sampling) and 6.8% for coconut forecasts in Sri Lanka. However, our somewhatdisappointing results were mainly due to a series of poor crops attributed to human reasons, which have now been factored into the models. Notably, the 2012 and 2013 forecasts averaged 7.8 and 4.9% errors, respectively. Future models should also show continuing improvement, as more data-years become available.
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Le genre Angraecum est un groupe d’orchidées tropicales qui compte environ 221 espèces réparties en Afrique subsaharienne, dans l’ouest de l’Océan Indien, et au Sri Lanka. Plus de la moitié des espèces se trouvent à Madagascar, dont au moins 90% sont endémiques à l’île. L’étude systématique et taxonomique du genre Angraecum a toujours été problématique à cause de sa grande diversité morphologique. Pour faciliter la classification, des sections ont été établies dont la plus connue est celle de Garay (1973), qui regroupe les espèces sous 19 sections. Plusieurs analyses phylogénétiques avaient montré que le genre Angraecum et les sections de Garay ne sont pas monophylétiques. Cependant, aucune révision systématique n’a été apportée à cause du faible échantillonnage dans ces analyses. En incorporant un plus grand nombre d'espèces et en ajoutant d’autres caractères morphologiques dans l’analyse, nous avons apporté une plus grande résolution à la reconstruction phylogénétique du groupe. Cette résolution concerne surtout les nœuds plus profonds qui représentent les différents clades à l’intérieur d'Angraecum, qui correspondent à des sections naturelles. A partir de ces clades, nous avons redéfini 14 sections monophylétiques toute en reconnaissant cinq nouvelles. Grâce à cette nouvelle phylogénie d'Angraecum, nous avons pu étudier la diversification du genre et de la sous-tribu Angraecinae en utilisant des méthodes macroévolutives, notamment les roles joués par les traits floraux dans la spéciation, tout en l'interprétant grâce aux histoires géologique et paléoclimatique. Le modèle de diversification chez les Angraecinae semble avoir été celui communément rencontré dans les forêts tropicales humides, c’est-à-dire une diversification par accumulation graduelle d’espèces à travers le temps et non pas une radiation adaptative rapide, comme souvent observée chez des lignées animales malgaches. Plusieurs caractères morphologiques jouent un rôle important dans la diversification des espèces d'Angraecum. Le début de la diversification d'Angraecum à Madagascar coïncide avec le mouvement progressif de l’île vers le nord, l’établissement de la mousson dans la partie nord de l’île durant le Miocène, et l’expansion de la forêt tropicale malgache pendant cette période. Notre étude de l’histoire biogéographique des Angraecinae suggère une origine malgache de la sous-tribu et du genre Angraecum. On observe de la dispersion à longue distance à partir de Madagascar vers le reste du monde dans le genre Angraecum. La forêt tropicale humide du Nord Est de Madagascar est le point de départ de la diversification des espèces d'Angraecum. Le premier événement de dispersion a débuté à l’intérieur de l’île vers la fin du Miocène. Cet évènement est marqué par une migration du Nord Est vers le centre de Madagascar. Par ailleurs, la majorité des événements de dispersion à longue distance se sont produits durant le Pliocène-Pléistocène à partir soit du centre, soit du Nord Est de l'île. On assiste à des migrations indépendantes vers l’Afrique de l’est et les Comores d’une part, et vers les Mascareignes d’autre part. Un seul événement fondateur ayant conduit à l’apparition de la section Hadrangis est observé dans les Mascareignes. La saison cyclonique joue un rôle significatif dans la dispersion à longue distance des graines d’orchidées, comparée aux vents dominants qui soufflent dans la région ouest de l’Océan Indien, notamment l’alizé et la mousson. La similarité des niches écologiques a facilité l’expansion des espèces d'Angraecum dans les Comores et les Mascareignes.
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El interés de esta monografía es analizar las consecuencias de la representación institucional de India y Paquistán en la disputa territorial por Cachemira durante el periodo de 1989 a 2008. Puntualmente, se analiza y explica cómo la representación institucional prestada individualmente por India y Paquistán validó sus intereses como agentes de poder en la región, pasó por alto las necesidades de la población cachemir y fomentó la práctica de la desaparición forzada, lo que en consecuencia convirtió a las mujeres cachemires en un grupo subalterno. Para tal objetivo, se hará uso de la teoría postcolonialista, específicamente el enfoque subalternista de la autora Gayatri Chakravorty Spivak ya que permite explicar adecuadamente el proceso mediante el cual las mujeres cachemires se convirtieron en un grupo subalterno.
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El objetivo de este estudio de caso es describir y analizar los intereses nacionales desde la concepción de India y Noruega durante el contexto histórico del conflicto en Sri Lanka, además examinar cómo estos intereses influenciaron la consolidación de las estrategias y tácticas de negociación. La hipótesis aprobar es que las mediaciones de India y Noruega se desarrollan de forma distinta debido a sus intereses, sin embargo, ambas lograron formas de entendimiento entre el Gobierno de esrilanqués y el Grupo Insurgente Tigres de Liberación de la Tierra Tamil (LTTE). Para esto, se revisan los límites de las mediaciones conforme a los intereses. Siguiendo distintas perspectivas académicas del realismo, neorrealismo y cientificismo se utilizan distintos conceptos desarrollados por Hans Morgentau, Robert Osgood, Johan Galtung, Oliver Ramsbothan, Saddia Touval e Isak Svensson. Desde el método descriptivo histórico y análisis cuantitativo se describen los intereses nacionales y su influencia en las mediaciones que se llevaron a cabo en Sri Lanka.
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O crescimento da população gerou a ocupação de grandes áreas da superfície terrestre que provocaram alterações nas paisagens naturais. A apropriação desordenada do território, tendo em conta os espaços urbanos e rurais, trouxe vários impactos negativos ao meio ambiente. As linhas de água são os ecossistemas mais utilizados pelo homem ao longo da história, pela água, pesca, transporte, … e que simultaneamente vai modelando a paisagem pelas alterações do estado físico e modificações nas superfícies por onde corre. O sistema ribeirinho é constituído por vários ecossistemas, relacionados entre si e que são identificados transversalmente. Ao longo do ano é possível identificar, numa linha de água, três níveis: o de cheia durante o escoamento máximo anual no período das chuvas, o médio ao longo do ano e o de estiagem com o escoamento mínimo no pico do verão. Nas margens, a zonagem das espécies ripárias, está relacionada com a altitude, a unidade bioclimática, a distância do “eixo de humidade”, a geomorfologia, o tipo de solos e a matéria orgânica, entre outros fatores. Nas galerias ripícolas do Alentejo são frequentes cinco comunidades vegetais com grande diversidade de espécies, cujas presenças estão relacionadas com os níveis de água ao longo do ano e o tipo de solo: a) Choupais (Populus nigra), em solos sujeitos a prolongados encharcamentos. b) Salgueirais de borrazeiras pretas (Salix atrocinerea), em ribeiras com regime torrencial. c) Amiais (Alnus glutinosa), em solos com toalha freática à superfície. d) Freixiais (Fraxinus angustifolia) em solos húmidos, a comunidade mais comum no Alentejo. A vegetação marginal constitui um sistema elástico importante na proteção mecânica das margens contra o desgaste normal das águas, porque as mantêm seguras, protege o leito, favorece a riqueza piscícola e purifica as águas. Na proteção com sistemas rígidos e impermeáveis, verifica-se um elevado custo e estabilidade ameaçada nos pontos de contacto com as margens naturais, impede a comunicação natural entre a água que corre no leito do rio e a que se desloca em toda a largura do vale, provocando alterações no lençol freático. São vários, os valores associados à paisagem ribeirinha e, a titulo de exemplo, destacam-se: a) Simbólico: o Taj Mahal nas margens do rio Yamuna em Agra – Índia, classificado como Património da Humanidade pela UNESCO (1980) e a ponte Hintze Ribeiro destinada a unir as margens de Entre-os-Rios, em Penafiel e Castelo de Paiva, sobre o rio Douro e que colapsou em 4 de março de 2001, num acidente que provou 59 mortes. b) Histórico: a ponte medieval de San Martín (séc. XIV.) em Toledo – Espanha; o açude e termas romanas do séc. I a IV a.C., na Herdade de Almagrassa (Pisões) – Portugal e a villa romana da Tourega (séc. I a IV) que pertenceu ao senador Julius Maximus (Ivlivs Maximvs), como consta da lapide funerária encontrada na N. Sra. da Tourega (Évora) – Portugal. c) Mítico: a ponte romana em Cangas de Onís com a Cruz de la Victoria no principado de Astúrias – Espanha. d) Cultural: a atividade diária nas margens do rio Kottayam no distrito de Kerala – Índia; um fim de semana na margem do rio Danúbio na cidade de Viena – Aústria; as várzeas de rios goeses: Loutulim (Rio Zuari), Benaulim (represa de Komollam Tollem) e Betul (rio Sal) (Goa) – Índia e várzeas de rios cingaleses (região de Kandy) – Sri Lanka. e) Turístico: o palácio real de verão mandado construir pelo marajá Jagat Singh II (1734-1751) na ilha de Jag Niwas (1,5 ha) no lago Pichola. No fim da década de 60, tornou-se num dos mais famosos hotéis românticos do mundo, o Lake Palace Hotel – Índia e a queda de água de Karpuzkaldiran próximo da cidade de Antalya, cujo acesso é feito por escadas ou de barco – Turquia.
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Mode of access: Internet.
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Mechanically evoked reflexes have been postulated to be less sensitive to presynaptic inhibition (PSI) than the H-reflex. This has implications on investigations of spinal cord neurophysiology that are based on the T-reflex. Preceding studies have shown an enhanced effect of PSI on the H-reflex when a train of ~10 conditioning stimuli at 1 Hz was applied to the nerve of the antagonist muscle. The main questions to be addressed in the present study are if indeed T-reflexes are less sensitive to PSI and whether (and to what extent and by what possible mechanisms) the effect of low frequency conditioning, found previously for the H-reflex, can be reproduced on T-reflexes from the soleus muscle. We explored two different conditioning-to-test (C-T) intervals: 15 and 100 ms (corresponding to D1 and D2 inhibitions, respectively). Test stimuli consisted of either electrical pulses applied to the posterior tibial nerve to elicit H-reflexes or mechanical percussion to the Achilles tendon to elicit T-reflexes. The 1 Hz train of conditioning electrical stimuli delivered to the common peroneal nerve induced a stronger effect of PSI as compared to a single conditioning pulse, for both reflexes (T and H), regardless of C-T-intervals. Moreover, the conditioning train of pulses (with respect to a single conditioning pulse) was proportionally more effective for T-reflexes as compared to H-reflexes (irrespective of the C-T interval), which might be associated with the differential contingent of Ia afferents activated by mechanical and electrical test stimuli. A conceivable explanation for the enhanced PSI effect in response to a train of stimuli is the occurrence of homosynaptic depression at synapses on inhibitory interneurons interposed within the PSI pathway. The present results add to the discussion of the sensitivity of the stretch reflex pathway to PSI and its functional role.
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We propose a method for measuring hyper-Rayleigh scattering employing pulse trains produced by a Q-switched and mode-locked Nd:YAG laser. The use of the entire pulse train under the Q-switch envelope avoids the need of any device to scan the irradiance, as is usually done with nanosecond and femtosecond single-pulse lasers. To verify the feasibility of the technique, we performed measurements in different solutions of para-nitroaniline and compared the results with those obtained with nanosecond pulses. In both cases, the agreement with the hyperpolarizability values reported in the literature is about the same, but the measurements carried out with pulse trains are at least 20 times faster. Besides the advantage of acquisition speed, the use of pulse trains also allows the instantaneous inspection of slow luminescence contributions arising from multiphoton absorption. (C) 2008 Optical Society of America.
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The top velocity of high-speed trains is generally limited by the ability to supply the proper amount of energy through the pantograph-catenary interface. The deterioration of this interaction can lead to the loss of contact, which interrupts the energy supply and originates arcing between the pantograph and the catenary, or to excessive contact forces that promote wear between the contacting elements. Another important issue is assessing on how the front pantograph influences the dynamic performance of the rear one in trainsets with two pantographs. In this work, the track and environmental conditions influence on the pantograph-catenary is addressed, with particular emphasis in the multiple pantograph operations. These studies are performed for high speed trains running at 300 km/h with relation to the separation between pantographs. Such studies contribute to identify the service conditions and the external factors influencing the contact quality on the overhead system. (C) 2013 Elsevier Ltd. All rights reserved.
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In this paper analytical transient solutions of dynamic response of one-dimensional systems with sudden change of foundation stiffness are derived. In more details, cantilever dynamic response, expressed in terms of vertical displacement, is extended to account for elastic foundation and then two cantilever solutions, corresponding to beams clamped on left and right hand side, with different value of Winkler constant are connected together by continuity conditions. The internal forces, as the unknowns, can be introduced by the same values in both clamped beam solutions and solved. Assumption about time variation of internal forces at the section of discontinuity must be adopted and originally analytical solution will have to include numerical procedure.
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Passage of high-speed trains may induce high ground and track vibrations, which, besides increasing wheel, rail and track deterioration, may have a negative impact on the vehicle stability and on the passengers comfort. In this paper two distinct analyses are presented. The first one is dedicated to efficient decoupling of rail and soil vibrations by suggesting new interface materials in rail-sleeper fixing system, i.e. in the part where damping efficiency can be directly controlled and tested. The second analysis concerns with an adequate model of soils damping. Proper understanding and correct numerical simulation of this behaviour can help in suggesting soil improvement techniques.