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141.
This paper is an initial exploration of inter-industry relationships and linkages in the context of automobile imports to the United States. It is our contention that the nature and structure of the engagement between automobile importers and shipping lines is central to understanding the evolution of the car carrier trade. Building on the literature on transactions costs, and supply and value chains, we show that the regimes currently governing car carriage services range from markets to vertical integration via network forms of engagement. We illustrate this through a detailed discussion of Japanese inter-firm networks and an examination of automobile import data to the US from 1980 to 2000. The findings raise important questions for future research on the impact of inter-industry relationships in various strategic decisions of steamship lines, shippers and port authorities including port entry, port choice and routeing, technological and investment choices, and trajectories of supply chain development.  相似文献   
142.
In this paper, we measure the relations between stated and revealed car preferences and the use of information sources in the car-purchasing process, based on a survey of households in the Netherlands. The analysis showed that attitudinal and behavioral constructs are found for ‘environmental’, ‘performance’, and ‘convenience’ preferences, but that there is a ‘gap’ between attitude and behavior. The results show that people with a positive environmental attitude who also show environmentally friendly behavior have more involvement with cars than people who do not translate their environmental attitude into the corresponding behavior. This leads to the idea that not only environmental knowledge but also involvement with cars is a prerequisite for buying an environmentally friendly car.  相似文献   
143.
Driver satisfaction regarding travel information provided by variable message signs (VMS), which are part of the Nam‐Mountain Tunnel ATIS, was evaluated using fuzzy aggregation. Application of fuzzy aggregation to analyze driver satisfaction allows one to represent the variability and complexity of human perception with great fidelity. A fuzzy weighted average using two sets of fuzzy membership functions was applied to evaluate individual satisfactions of delay and travel time information provided. Then, those individual satisfactions were aggregated to estimate the driver group's overall satisfaction. The evaluated overall satisfaction was 0.65 for delay information and 0.63 for travel time information. Through these results, it was found that users of the travel information provided by the VMS in the Nam‐Mountain Tunnel ATIS were somewhat satisfied with the service quality. Those overall satisfactions were compared with a conventional weighted average and traffic operational effects to demonstrate the usefulness of the developed fuzzy method.  相似文献   
144.
The French Aquitaine region has implemented a climate plan to avoid 2,883 ktCO2eq for 2007–2013. Although this region reduced its greenhouse gas (GHG) emissions by 1,119 ktCO2eq between 1990 and 2005 (from 24,061 ktCO2eq to 22,942 ktCO2eq), GHG emissions of transports sector has increased by 762 ktCO2eq. During the climate plan period, the region will implement projects of road and rail infrastructures construction in order to absorb the foreseen increase of traffic. These projects will contribute to economic development, but they also will provoke additional GHG emissions. But, the existence of a climate plan requires offsetting these GHG emissions. A maximum amount of budget will be determined in order to implement some projects to offset GHG emissions from road and rail projects. This budget will be equal to opportunity costs of road and rail projects. Input-output analysis will be used to carry out these calculations. Its interest is to incorporate the complexity of interindustrial trade with a detailed sectored study.  相似文献   
145.
Martin Wachs 《Transportation》2013,40(6):1159-1172
North American urban areas have changed dramatically over the last four decades. While downtowns were thought to be in long-term decline 40 years ago, central business districts are today the most vibrant residential and commercial centers throughout a largely suburban continent. This paper examines the role of transportation technology and policy in the earlier decline and recent revival of American downtowns and examines challenges to the continuation of urban regeneration. Major recent investments in physical improvements in central cities have been complemented by a dramatic shift in the locus of logistical and goods processing activities from city centers to outlying areas. While many tout the energy efficiency and environmental benefits of walkable and denser inner cities, a more complete accounting of their impacts also requires analysis of increasing urban congestion and the steady rise in urban goods movement in support of the new development patterns.  相似文献   
146.
1988年的概念车是跟小家碧玉毫不沾边的风格o汽车产业在第二次爱之夏时为之疯狂。1988年,乔治·布什刚当选美国总统。而在底特律,凯迪拉克Voyage也在另一场备受关注的选举中脱颖而出,成为这场秀的明星。这辆轿车外观时髦.像  相似文献   
147.
This paper proposes a new method for combining the lifetime wave-induced sectional forces and moments that are acting on the ship structure. The method is based on load simulation and can be used to determine the exceedance probabilities of any linear and nonlinear long-term load combination. It can also be used to determine the long-term correlation structure between these loads in the form of the long-term correlation coefficients. They are essential part of the load combination procedures in design and strength evaluations as well as in the fatigue and reliability analysis of ship structures.The simulation method treats the non-stationary wave elevations during the ship’s entire life (long-term) as a sequence of different stationary Gaussian stochastic processes. It uses the rejection sampling technique for the sea state generation, depending on the ship’s current position and the season. Ship’s operational profile is then determined conditional on the current sea state and the ship’s position along its route. The sampling technique significantly reduces the number of sea state-operational profile combinations required for achieving the convergence of the long-term statistical properties of the loads. This technique can even be used in combination with the existing long-term methods in order to reduce the number of required weightings of the short-term CDFs. The simulation method does, however, rely on the assumption that the ship is a linear system, but no assumptions are needed regarding the short-term CDF of the load peaks.The load time series are simulated from the load spectra in each sea state, taking into account the effects of loading condition, heading, speed, seasonality, voluntary as well as involuntary speed reduction in severe sea states and the short-crested nature of the ocean waves. During the simulation procedure, special care has been given to maintaining the correct phase relation between all the loads. Therefore, time series of various load combinations, including the nonlinear ones, can be obtained and their correlation structure examined. The simulation time can be significantly reduced (to the order of minutes rather than hours and days) by introducing the seasonal variations of the ocean waves into a single voyage simulation. The estimate of the long-term correlation coefficient, obtained by simulating only a single voyage with the correct representation of seasonality, approaches the true correlation coefficient in probability. This method can be applied to any ship and any route, or multiple routes as long as the percentage of the ship’s total lifetime spent in each of them is known.A study has been conducted to investigate the effects of ship type, route and the longitudinal position of the loads on the values of the correlation coefficients between six different sectional loads; vertical, horizontal and twisting moments, as well as shear, horizontal and axial forces. Three ocean-going ship types have been considered; bulk carrier, containership and tanker, all navigating on one of the three busy ship routes; North America-Europe, Asia-North America and Asia-Europe. Finally, the correlation coefficient estimates have been calculated for five different positions along the ship’s length to investigate the longitudinal variation of the correlation coefficient.  相似文献   
148.
Transportation policy in America distinguishes between capital expenditures and recurrent operating and maintenance costs. Federal policy and resources encourage capital-intensive projects, but traditionally have left to state and local governments the responsibility for maintaining and operating the facilities built with federal support. This has led to consistent underestimation of operating costs in the decision process leading to capital expenditures, and to overcapitalization of transportation networks. Today, faced with recurrent costs which strain local resources, there is pressure to broaden federal participation in operations and maintenance, and legislation is beginning to weaken the traditional distinctions between capital and recurrent expenditures.  相似文献   
149.
150.
汽车部件对污染的敏感性   总被引:1,自引:0,他引:1  
污染敏感性分析是实现对整个机械系统污染控制的重要步骤。通过对污染的分析、测试、建模及模拟分析可有助于减少污染物或微小颗粒对机械系统造成的污染,避免因污染而导致的系统故障。对有关汽车机械系统污染的问题进行了分类讨论并进行了相关性分析,对测试及计算机建模方法进行了论述。给出了污染敏感性分析流程,最后通过几个典型实例阐明了污染敏感性分析的意义。  相似文献   
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