Adaptive cruise control design for active congestion avoidance

We present an adaptive cruise control (ACC) strategy where the acceleration characteristics, that is, the driving style automatically adapts to different traffic situations. The three components of the concept are the ACC itself, implemented in the form of a car-following model, an algorithm for the automatic real-time detection of the traffic situation based on local information, and a strategy matrix to adapt the driving characteristics (that is, the parameters of the ACC controller) to the traffic conditions. Optionally, inter-vehicle and infrastructure-to-car communication can be used to improve the accuracy of determining the traffic states. Within a microscopic simulation framework, we have simulated the complete concept on a road section with an on-ramp bottleneck, using empirical loop-detector data for an afternoon rush-hour as input for the upstream boundary. We found that the ACC vehicles improve the traffic stability and the dynamic road capacity. While traffic congestion in the reference scenario was completely eliminated when simulating a proportion of 25% ACC vehicles, travel times were already significantly reduced for much lower penetration rates. The efficiency of the proposed driving strategy even for low market penetrations is a promising result for a successful application in future driver assistance systems.     

电子系统集成:汽车技术创新的驱动力

越来越多的机械和液压系统已经成为全电动或由电子控制。消费者不仅需要信息娱乐系统,他们对安全、动力传动系统、舒适/便利性、驾驶辅助系统的兴趣也在增长。     

International cooperation against piracy: China's role,problems, and prospects

While there are some non-contentious issues about which states can cooperate, most must be molded around the demands of national interest. Piracy is a case where suppression would appear to be in the interest of all states; after all, pirates have been regarded as the enemies of all since Roman times. Despite this, states have often been more ambivalent as they have found piracy to be a useful cloak behind which to hide their wider geo-strategic ambitions. This paper notes that Somali piracy has attracted the interest of China whose citizens have been attacked and hijacked. It asks if this deployment demonstrates that China is committed to the protection of shipping in the context of the existing maritime order or if it has a wider purpose to advance Chinese interests in the Indian Ocean region.     

The container terminal community

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.     

Consumer car preferences and information search channels

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.     

Evaluation of driver satisfaction of travel information on variable message signs using fuzzy aggregation

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.     

Coûts d’opportunité de construction des infrastructures routières et ferroviaires en Aquitaine pour la période 2007–2013 sous contrainte du Plan climat régional

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.     

Turning cities inside out: transportation and the resurgence of downtowns in North America

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.     

回到1988年的未来

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