937 resultados para Coupled Analysis, SPH, Plastic Road Safety Barriers, Impact, Non-structural Mass


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We assess Indian summer monsoon seasonal forecasts in GloSea5-GC2, the Met Office fully coupled subseasonal to seasonal ensemble forecasting system. Using several metrics, GloSea5-GC2 shows similar skill to other state-of-the-art forecast systems. The prediction skill of the large-scale South Asian monsoon circulation is higher than that of Indian monsoon rainfall. Using multiple linear regression analysis we evaluate relationships between Indian monsoon rainfall and five possible drivers of monsoon interannual variability. Over the time period studied (1992-2011), the El Nino-Southern Oscillation (ENSO) and the Indian Ocean dipole (IOD) are the most important of these drivers in both observations and GloSea5-GC2. Our analysis indicates that ENSO and its teleconnection with the Indian rainfall are well represented in GloSea5-GC2. However, the relationship between the IOD and Indian rainfall anomalies is too weak in GloSea5-GC2, which may be limiting the prediction skill of the local monsoon circulation and Indian rainfall. We show that this weak relationship likely results from a coupled mean state bias that limits the impact of anomalous wind forcing on SST variability, resulting in erroneous IOD SST anomalies. Known difficulties in representing convective precipitation over India may also play a role. Since Indian rainfall responds weakly to the IOD, it responds more consistently to ENSO than in observations. Our assessment identifies specific coupled biases that are likely limiting GloSea5-GC2 prediction skill, providing targets for model improvement.

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Friction plays a key role in causing slipperiness as a low coefficient of friction on the road may result in slippery and hazardous conditions. Analyzing the strong relation between friction and accident risk on winter roads is a difficult task. Many weather forecasting organizations use a variety of standard and bespoke methods to predict the coefficient of friction on roads. This article proposes an approach to predict the extent of slipperiness by building and testing an expert system. It estimates the coefficient of friction on winter roads in the province of Dalarna, Sweden using the prevailing weather conditions as a basis. Weather data from the road weather information system, Sweden (RWIS) was used. The focus of the project was to use the expert system as a part of a major project in VITSA, within the domain of intelligent transport systems

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The annual cost of home care services of transport in Falun/Borlänge, is now at 31 million kronor. It is clear from previous research that it is possible to reduce these costs through a restructuring of the existing home-help service. The restructuring aims to have a higher proportion of older people, who are in need of care, to live in special accommodation, in order to reduce transport costs. Therefore there is a need for systems that allow home-help service to plan their operations in such a way that transport is working as efficiently as possible. Through better planning, there are profits to be done. The rewards are not only of an economic nature but also include a reduced environmental impact, better working environment, improving road safety, and better service. One way to achieve this is to give home-help service personnel better navigation aid when they move between the customers. The thesis describes such a solution through a developed prototype based on a standardized interaction between a planning and a navigation service. The thesis describes such a solution through a developed prototype based on a standardized interaction between a planning and a navigation service. Development work has also been a first step in developing a standardized information infrastructure for home-help service. The purpose of the thesis is, on the basis of theory and the experience we have acquired through the development of the prototype, to discuss general issues which are of interest when developing standardized information infrastructure.

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Optimal location on the transport infrastructure is the preferable requirement for many decision making processes. Most studies have focused on evaluating performances of optimally locate p facilities by minimizing their distances to a geographically distributed demand (n) when p and n vary. The optimal locations are also sensitive to geographical context such as road network, especially when they are asymmetrically distributed in the plane. The influence of alternating road network density is however not a very well-studied problem especially when it is applied in a real world context. This paper aims to investigate how the density level of the road network affects finding optimal location by solving the specific case of p-median location problem. A denser network is found needed when a higher number of facilities are to locate. The best solution will not always be obtained in the most detailed network but in a middle density level. The solutions do not further improve or improve insignificantly as the density exceeds 12,000 nodes, some solutions even deteriorate. The hierarchy of the different densities of network can be used according to location and transportation purposes and increase the efficiency of heuristic methods. The method in this study can be applied to other location-allocation problem in transportation analysis where the road network density can be differentiated. 

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O trabalho apresenta uma avaliação dos prováveis impactos do escalonamento dos horários das aulas noturnas em uma Universidade. Neste trabalho foi investigada, a preferência dos usuários quanto às possíveis alterações nos horários de entrada de aulas, e os impactos do escalonamento na rede viária no entorno do campus. O trabalho envolveu a construção de diversos cenários de alterações nos horários de início das aulas. Os cenários foram construídos visando atender as preferências da população universitária e reduzir a interferência do pico de chegada de alunos no sistema viário. A avaliação dos impactos destes cenários no tráfego foi realizada através de simulação, com a utilização do modelo TSIS/NETSIM. As análises foram baseadas em dois indicadores de desempenho: a velocidade média e o tempo de atraso médio na rede.

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Software Products Lines (SPL) is a software engineering approach to developing software system families that share common features and differ in other features according to the requested software systems. The adoption of the SPL approach can promote several benefits such as cost reduction, product quality, productivity, and time to market. On the other hand, the SPL approach brings new challenges to the software evolution that must be considered. Recent research work has explored and proposed automated approaches based on code analysis and traceability techniques for change impact analysis in the context of SPL development. There are existing limitations concerning these approaches such as the customization of the analysis functionalities to address different strategies for change impact analysis, and the change impact analysis of fine-grained variability. This dissertation proposes a change impact analysis tool for SPL development, called Squid Impact Analyzer. The tool allows the implementation of change impact analysis based on information from variability modeling, mapping of variability to code assets, and existing dependency relationships between code assets. An assessment of the tool is conducted through an experiment that compare the change impact analysis results provided by the tool with real changes applied to several evolution releases from a SPL for media management in mobile devices

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omeprazole is a substituted benzimidazole which suppresses gastric-acid secretion by means of H+, K+-ATPase inhibition. It is an optically active drug with the sulfur of the sulfoxide being the chiral center. This pro-drug can be easily converted into its respective sulfenamide at low pH. In this work, omeprazole has been studied in relation to racemization barrier and decomposition reaction. Quantum chemistry coupled to PCA chemometric method were used to find all minimum energy structures. Conformational analysis and calculation of racemization barriers were carried out by PM3 semiempirical method (Gaussian 98). The average racemization energy barrier for all minimum energy structures (43.56 kcal mol(-1)) can be related to the velocity constant in Eyring's equation. The enormous half-life time at 100 degrees C (9.04 x 10(4) years) indicates that the process cannot be observed in human time scale. on the other hand, the difference of free energy change (Delta(Delta G) = -266.78 kcal mol(-1)) for the decomposition reaction shows that the process is favorable to the sulfenamide formation. The highly negative Delta(Delta G) obtained for the decomposition reaction shows that this process is extremely exothermic. This result explains why omeprazole decomposes and does not racemize. (C) 2008 Wiley Periodicals, Inc.

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This edition of the FAL Bulletin approaches road safety and the need for urgent, coordinated measures to be established between the public and private sectors and civil society in order to prevent the rapid increase in deaths and casualties in road accidents in Latin America and the Caribbean, an issue which is threatening the sustainability of regional development.

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O trânsito é caracterizado como uma questão de saúde pública pela Organização Mundial da Saúde. O grande número de acidentes de trânsito não retira deste fato o status calamitoso que o mesmo detém, o que acaba por corroborar a preocupação das Nações Unidas em relação ao aumento progressivo da violência no trânsito, o que a fez proclamar a Década de Ação pela Segurança no Trânsito 2011/2020 em consequência da gravidade da situação, que vem ceifando mais vidas do que nos períodos de guerra, o que é corroborado pela constatação do crescimento em 24% do número total de óbitos por acidentes com transporte, no período de 2002 a 2010 pelo Sistema de Informações de Mortalidade da Organização Mundial da Saúde, revelando a importância social desta dissertação, que tem como objetivo identificar os fatores potencializadores de acidentes de trânsito com vitimizações fatais ocorridos na rodovia BR 316 nos quilômetros 21 ao 278, no período de 2010 a 2012. Para tanto, lançou-se mão de uma metodologia baseada em explorações teóricas aliadas a análises de informações provenientes do banco de dados da Polícia Rodoviária Federal que foram tratados a partir da aplicação de técnicas estatísticas descritivas e multivariadas a fim de confirmar a hipótese suscitada. Diante disto, pode-se concluir que o ano de 2011 foi o período marcado pelo maior número de ocorrências, ocorrências estas que se tornaram mais frequentes nos meses de junho, julho e dezembro, respectivamente, os quais se concentraram no turno da tarde e causados, sobretudo, pela falta de atenção, a desobediência à sinalização e a falta de guarda da distância de segurança; saliente-se o fato de que nos turnos da madrugada e noite os acidentes mais frequentes foram causados por ultrapassagens indevidas, condutores dormindo ao volante, defeitos na via e a ingestão de álcool e ainda vale antecipar, que nos intervalos de quilômetros de 41 a 50, 91 a 100, 101 a 110, 121 a 130, 141 a 150, 151 a 160, 201 a 210, 231 a 240, 251 a 260 e 261 a 270 da BR 316, é frequente que dos acidentes que ocorrem resultem dois ou mais feridos graves, sendo que destes feridos graves, nos intervalos de quilômetros 91 a 100 e 121 a 130, 221 a 230, dois ou mais venham a falecer. Desta forma, conclui-se que nos intervalos quilômetros 91 a 100 e 121 a 130, os feridos graves inevitavelmente faleceram. Diante disto, pode-se observar que o efetivo sentido de cidadania que deve ser dado às relações que se configuram a partir da utilização consciente do trânsito está perdido em meio a uma crise moral de sentidos, especialmente, em relação à obediência às leis de trânsito, o que acaba por transformar a rodovia BR 316 em um cenário de perdas iminentes de vidas, sobretudo, quando se remete ao fato de que todo o acidente de trânsito é previsível e evitável.

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Pós-graduação em Ciências Cartográficas - FCT

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Pós-graduação em Engenharia Elétrica - FEIS

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In this paper we use a coupled ocean-atmosphere model to investigate the impact of the interruption of Agulhas leakage of Indian ocean water on the tropical Atlantic, a region where strong coupled ocean-atmosphere interactions occur. The effect of a shut down of leakage of Indian ocean water is isolated from the effect of a collapse of the MOC. In our experiments, the ocean model is forced with boundary conditions in the southeastern corner of the domain that correspond to no interocean exchange of Indian ocean water into the Atlantic. The southern boundary condition is taken from the Levitus data and ensures an MOC in the Atlantic. Within this configuration, instead of warm and salty Indian ocean water temperature (cold) and salinity (fresh) anomalies of southern ocean origin propagate into the South Atlantic and eventually reach the equatorial region, mainly in the thermocline. This set up mimics the closure of the ""warm water path"" in favor of the ""cold water path"". As part of the atmospheric response, there is a northward shift of the intertropical convergence zone (ITCZ). The changes in trade winds lead to reduced Ekman pumping in the equatorial region. This leads to a freshening and warming of the surface waters along the equator. Especially in the Cold Tongue region, the cold and fresh subsurface anomalies do not reach the surface due to the reduced upwelling. The anomaly signals are transported by the equatorial undercurrent and spread away from the equator within the thermocline. Part of the anomaly eventually reaches the Tropical North Atlantic, where it affects the Guinea Dome. Surprisingly, the main effect at the surface is small on the equator and relatively large at the Guinea Dome. In the atmosphere, the northward shift of the ITCZ is associated with a band of negative precipitation anomalies and higher salinities over the Tropical South Atlantic. An important implication of these results is that the modified water characteristics due to a shut down of the Agulhas leakage remain largely unaffected when crossing the equatorial Atlantic and therefore can affect the deepwater formation in the North Atlantic. This supports the hypothesis that the Agulhas leakage is an important source region for climate change and decadal variability of the Atlantic.

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We estimate the impact of regulatory heterogeneity on agri-food trade using a gravity analysis that relies on detailed data on non-tariff measures (NTMs) collected by the NTM-Impact project. The data cover a broad range of import requirements for agricultural and food products for the EU and nine of its major trade partners. We find that trade is significantly reduced when importing countries have stricter maximum residue limits (MRLs) for plant products than exporting countries. For most other measures, due to their qualitative nature, we were unable to infer whether the importer has stricter standards relative to the exporter, and we do not find a robust relationship between these measures and trade. Our findings suggest that, at least for some import standards, harmonising regulations will increase trade. We also conclude that tariff reductions remain an effective means to increase trade even when NTMs abound.

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Introduction. Patients with terminal heart failure have increased more than the available organs leading to a high mortality rate on the waiting list. Use of Marginal and expanded criteria donors has increased due to the heart shortage. Objective. We analyzed all heart transplantations (HTx) in Sao Paulo state over 8 years for donor profile and recipient risk factors. Method. This multi-institutional review collected HTx data from all institutions in the state of Sao Paulo, Brazil. From 2002 to 2008 (6 years), only 512 (28.8%) of 1777 available heart donors were accepted for transplantation. All medical records were analyzed retrospectively; none of the used donors was excluded, even those considered to be nonstandard. Results. The hospital mortality rate was 27.9% (n = 143) and the average follow-up time was 29.4 +/- 28.4 months. The survival rate was 55.5% (n = 285) at 6 years after HTx. Univariate analysis showed the following factors to impact survival: age (P = .0004), arterial hypertension (P = .4620), norepinephrine (P = .0450), cardiac arrest (P = .8500), diabetes mellitus (P = .5120), infection (P = .1470), CKMB (creatine kinase MB) (P = .8694), creatinine (P = .7225), and Na+ (P = .3273). On multivariate analysis, only age showed significance; logistic regression showed a significant cut-off at 40 years: organs from donors older than 40 years showed a lower late survival rates (P = .0032). Conclusions. Donor age older than 40 years represents an important risk factor for survival after HTx. Neither donor gender nor norepinephrine use negatively affected early survival.

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Flood disasters are a major cause of fatalities and economic losses, and several studies indicate that global flood risk is currently increasing. In order to reduce and mitigate the impact of river flood disasters, the current trend is to integrate existing structural defences with non structural measures. This calls for a wider application of advanced hydraulic models for flood hazard and risk mapping, engineering design, and flood forecasting systems. Within this framework, two different hydraulic models for large scale analysis of flood events have been developed. The two models, named CA2D and IFD-GGA, adopt an integrated approach based on the diffusive shallow water equations and a simplified finite volume scheme. The models are also designed for massive code parallelization, which has a key importance in reducing run times in large scale and high-detail applications. The two models were first applied to several numerical cases, to test the reliability and accuracy of different model versions. Then, the most effective versions were applied to different real flood events and flood scenarios. The IFD-GGA model showed serious problems that prevented further applications. On the contrary, the CA2D model proved to be fast and robust, and able to reproduce 1D and 2D flow processes in terms of water depth and velocity. In most applications the accuracy of model results was good and adequate to large scale analysis. Where complex flow processes occurred local errors were observed, due to the model approximations. However, they did not compromise the correct representation of overall flow processes. In conclusion, the CA model can be a valuable tool for the simulation of a wide range of flood event types, including lowland and flash flood events.