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102.
The efficient utilization of expensive rolling-stock has become imperative for all railroads. In this paper, we study the combined empty and loaded train-scheduling problem for the upcoming dedicated freight corridors in India. Existing optimization models either do not consider the simultaneous optimization of the loaded and empty flows or are not solvable for large railroads. Our model is the first of its kind to incorporate link capacity constraints in an IP formulation for this operational level problem. A simulated annealing algorithm hybridized with a constructive heuristic is proposed as the solution method. The computational experiments show that the proposed heuristic performs well both in terms of runtime and solution quality. 相似文献
103.
《Ergonomics》2012,55(7):1131-1136
Thirty Canadian police officers, divided into six groups, participated in the redesign of the interior of the patrol car. Three of the groups consisted of individuals having a history of low back disease. The effect of participating in a design process on the characteristics of the final design and on the perception of the low back pain was studied in a semi-experimental setting. The participants developed a strong commitment to the participatory design process, which was reflected in their productions. The differences between participants with and without a history of a low back disease was not marked. The former tended to stress posture-related elements in their analysis and design. 相似文献
104.
Concerns about air quality and global warming have led to numerous initiatives to reduce emissions. In general, emissions are proportional to the amount of fuel consumed, and the amount of fuel consumed is a function of speed, distance, acceleration, and weight of the vehicle. In urban areas, vehicles must often travel at the speed of traffic, and congestion can impact this speed particularly at certain times of day. Further, for any given time of day, the observations of speeds on an arc can exhibit significant variability. Because of the nonlinearity of emissions curves, optimizing emissions in an urban area requires explicit consideration of the variability in the speed of traffic on arcs in the network. We introduce a shortest path algorithm that incorporates sampling to both account for variability in travel speeds and to estimate arrival time distributions at nodes on a path. We also suggest a method for transforming speed data into time-dependent emissions values thus converting the problem into a time-dependent, but deterministic shortest path problem. Our results demonstrate the effectiveness of the proposed approaches in reducing emissions relative to the use of minimum distance and time-dependent paths. In this paper, we also identify some of the challenges associated with using large data sets. 相似文献
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为满足客户日新月异的技术及运营需求,对车联网服务能力进行完善,发掘4G在新一代车联网应用中牵引作用,面向前装市场推出以云管端一体化为核心的和车连产品,引导车联网行业新变革. 相似文献
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Guilherme Wisnik 《Architectural Design》2016,86(3):20-27
An awakening interest in public space in Brazilian cities is emphasising the value of existing civic areas. Guilherme Wisnik , a critic, curator and professor at the Faculty of Architecture and Urbanism of the University of São Paulo, looks at the history and potential future of Brazil's urban spaces. He highlights how despite the introduction of innovative Modernist design in the mid-20th century, which forged ‘a new relationship between architecture, urbanism and landscape design’, more recently the country's cities have been subject to the vicissitudes of market and political forces. 相似文献
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随着城市和社会的不断发展,大城市成为了人口和建筑高度集中的地段,也成为了防灾避难场所规划重点地区。本文从日本,美国,中国三国防灾发展历程研究人手,思考如何构筑我国大城市防灾避难规划体系,提高城市防灾减灾能力。 相似文献