Biologie, transport, complexité

As a result of some of the analogies between biology and transport, including the concepts of evolution and selection, we are wondering whether some ideas and methods used in biology may not be used to provide research avenues within the field of transportation. We are interested in the idea of complexity, which is common to the two scientific fields, but not treated in the same way by either of the two disciplines. By observing the way in which systemic biology has developed, from a largely “data-driven” approach to research guided by data, we are questioning whether such a direction would be possible in the field of transportation. This investigation also leads us to ask questions about “modules”, or the boundaries of the subsystems studied in the field of transportation, through the observation that molecular biology defines these boundaries in terms of the function of the subsystems. In conclusion, we are expressing the notion that these comparisons will lead to new research avenues in the field of transportation.     

Choix d'itinéraires et péage urbain Le cas du tunnel Prado-Carénage, à Marseille

This paper has a dual aim. Firstly, to identify the principal factors which explain route choice among drivers to Marseille in the context of urban tolling and secondly to assess marginally willingness to pay in order to save time and improve travel conditions. For this purpose we have used of the results of a 1995 stated preference survey of potential users of the Prado-Carénage tunnel in Marseille. Initially the paper describes the changeover values-of-time using a conventional price-time model. The sample has also been broken down into three homogeneous behaviour classes for each of which a Logit model has been calibrated. Analysis of the results has confirmed that there is no single value-of-time there is rather one (or several) distribution curve(s) of maximum willingness to pay. This illustrates the diversity of individual preferences and behaviours and confirms our starting hypothesis, namely that there is not a single value of time but as many values as there are individuals and that each individual has a large number of values depending on the nature of the trip in question.     

Le projet isis: une interface intégrée de sécurité

In order to meet safety, reliability and availability constraints for passenger transport systems, the manufacturers of railway control-command systems must develop specific computer architectures for signalling, switch control and automatic driving applications. Typically, these systems consist of a core (with one or two central processing units) and peripherals via which the computer communicates with external devices. In the case of some applications, for example signal boxes, the architecture contains a very large number of fail-safe True or False outputs. These functionalities are currently performed by conventional technology that uses discrete components or hybrid circuitry.     

Un scénario périurbain de route automatisée

A scenario for a suburban automated highway with the objective of reducing congestion is described. Starting from a reference situation similar to a current traffic lane, the authors consider the influence of a number of parameters on the achievable capacity of an automated section of road. These parameters are used to estimate safe following distances which are computed with the aim of avoiding collisions in the event of sudden braking. They then consider the number of collisions in the presence of a brick wall type obstacle on the carriageway. Ramp metering based on a macroscopic approach leads to a loss of capacity, which we overcome by implementing a management technique that integrates individual vehicles in the stream. Lastly, a general architecture for the scenario with several control and co-ordination layers is proposed.     

忆往事,追未来,保时捷Cayenne Coupé用一天时间,品读襄阳南路的故事

花密码(襄阳南路340号)鲜花用五彩斑斓点缀着城市的每一个角落,鲜花包裹着爱,是日常的美好,是手边的信物。每一朵花,都有一种花语,每一束花,都有一份使命。年轻的情侣,白头的夫妻,久违的朋友,身边的同事,人们热爱鲜花的美丽,更感动于背后的深情。它们象征了不同的情感,为人们传递不同的心愿。一朵花瓣,一场风尘,一口香气,一个微笑,是那样的亲切,那样的永久。     

Gibraltar: le projet de lien fixe entre intégration euroméditerranéenne et développement régional

This paper presents a socioeconomic examination of the project for a fixed link in the Strait of Gibralter. This project for a major link between Europe and the Maghreb which would take the form of a rail tunnel can be examined at two different spatial scales, that of the major trade networks which link Europe and the Maghreb and that of the areas which are located near the future points of access to the tunnel. If we pass over the problems which may be posed by the financing of this project (which studies have shown to be profitable), the geopolitical context of changing relations within Europe and the Mediterranean should be favourable to its construction. Its strategic (and at the same time symbolic) character is defined by its role as a link between the trans-European networks and the southwestern shore of the Mediterranean basin. This physical connection may nevertheless generate undesired or even counterproductive effects in the directly exposed economies on the southern side. Additional strategies could be considered for which the existence of a tunnel would constitute an opportunity. These are referred to as accompanying measures in French regional planning policy.     

Une caractérisation de l'émission acoustique des véhicules au cours des déplacements

Traffic noise is usually measured at fixed points whereas in reality vehicles move and generate noise throughout their trip. This paper therefore puts forward a new method of identifying noise emissions which takes account of the trip as a whole. We have made use of the concept of standard kinematic sequences (which are the elements which form all car trips) and have introduced a new acoustic index to characterize the noise emissions of a vehicle during a sequence. We have achieved this by adapting conventional highway acoustic indices to the way sequences are defined and used. We have calculated examples of these indices from acoustic recordings of isolated vehicles on a test track and from standard sequences.     

Quelle place pour la sécurité routière dans les plans de déplacements urbains? Entre intégration et diffusion,le cas du plan de déplacements urbains de Lille métropole

This paper describes the position given to road safety in Urban Travel Plans by analyzing Urban Travel Plan document from eleven cities and undertakes a more in-depth investigation of road safety in the Urban Community of Lille. These plans provide an opportunity to disseminate knowledge about road safety to the other areas of urban management. They also describe the beginning of an integration of road safety in urban planning, even if intersectoral approaches at city level have yet to be developed and even if, in the case of Lille, the division of institutional competence with regard to the management of public space still requires clarification.