The implementation of automated speed enforcement (ASE) program necessarily involves a relationship with the territory concerned. This article analyses both these physical and conceptual relationships and the way the notion is transformed by the program itself, which offers a new interpretation. The first section sets out to demonstrate that while these programs function within administered territories, their effectuation leads to the creation of "conceptual territories." The programs are highly diverse and their variety is expressive of institutional, organizational and environmental characteristics. The second section sets out to analyze the constraints encountered by ASE programs in the context of different territorial contexts, which represent real hindrances to their functioning. Nonetheless it seems to be within the capacities of the programs to limit the impact of these constraints and to come up with innovative solutions.
Île-de-France constitutes a single perimeter of urban transport and the question of the bond between financing and tariffing is there all the more crucial, which makes tariffing a major stake, as well tariff as zonal. The article concentrates on the relevance to apply to commercial tariffing (the Navigo Step) a single tariff. During one time of delay in investments and budgetary scarcity, the Step with single tariff benefits only to 14% from the subscribers TC (Paris-Large crown), it causes a shortfall equivalent to the fifth of the receipts of ticketing, of about size of the investments in extensions of networks, its implementation being conditioned by the acquisition of new receipts. However, the current situation comprises already strong decreasing scales with the number of zones, and called upon territorial solidarity is prone to guarantee: the most modest households are located mainly east of the metropolis, in the rural sectors and in the urbanized sectors close to the heart of urban area, it is in the central zones that one finds the strongest percentages of households below the poverty line, the majority of the inhabitants of perish-urban wish to live into perish-urban, all the subscribers whose displacements are limited to two zones strongly see their tariffs increasing. The social solidarity is already exemplary. The Navigo Step and the Transilien logo contribute already to the regional identity. One cannot exclude an incentive with the urban sprawl. Especially the […]
For analyzing the reciprocal interaction between urban sprawl and car use, research has first focused on the link between urban density and mobility. By looking for a reduction in energy consumption, cities have favoured a compact planning development. Then reflection has broadened from the simple density to the wider, multi-dimensional concept of urban form. This controversy has led to a renewal of analysis in term of the costs of urban growth, notably by comparing the costs of "compact" and "sprawled" development. The idea is to compare the mobility costs of different urban forms. However, most often because of a lack of data, such studies are scarce. This paper suggests an innovative method to compute mobility costs at an infra-urban scale : The Spatialized Travel Account (STA). It is based on the CERTU's travel account methodology at a metropolitan scale. It puts forward an accurate estimate of the mobility costs for each transport mode (individual and public) and for each type of payer (households, firms, local authorities...). In order to test the relationships between mobility costs and urban form, we link the computed costs to morphological characteristics of infra-urban zones, taking in account sociodemographic characteristics of households.
Estimation of aggregated mode choice models has to face the problem of reliability of data used for calibration. Samples in travel surveys that are used for these estimations are generally too small for the needs of aggregate models. Therefore the number of observed trips per origin-destination is very small for the majority of them. Solution which is generally chosen needs on the one hand to reduce the number of zones by zones aggregation and on the other hand to keep for calibration only those origins-destinations for which sample size is above a minimum threshold. But we demonstrated that calibration results are highly sensitive to the choice of zones aggregation and to the choice of the threshold. In response to this problem this paper proposes an estimation method which allows very small-scale zoning to be retained and to keep the available information. The method is based on an iterative process whose convergence appears quite rapid and more importantly gives stable calibration results regarding zoning and threshold choices. To overcome one of the main problems of this method, which do not allow the calculation of confidence interval, we have used bootstrap method. This empirical analysis of mode choice between car and public transport on Lyon data allows us to study the benefits of our method in comparison with more conventional methods.
To quantify the impact of a variation of the diesel oil price on road freight transport, we look at the evolution of the freight demand expressed in tons.kilometers (t.km) on the one hand and in vehicles.kilometers (veh.km) on the other hand, according to the evolution of the diesel oil price. We use the quarterly series of the TRM (Road Freight Transport) survey on road freight transport demand and the data of the CNR (Comité National Routier) for the diesel oil price. Road Freight transport demand is sensitive to changes in fuel price. Using the log-log model, we found constant road freight demand elasticity to diesel oil price of -0.3 for t.km as well as veh.km. In fact these elasticities are not constant. Introducing the time as an explanatory variable we found that t.km elasticity varied from -0.25 at the beginning of 1998 down to -0.40 at the end of 2010 and veh.km from -0.28 down to -0.48: demand is increasingly sensitive to changes in fuel price.
The essential role of the inter-ocean canals in opening up new maritime routes should never be underestimated. Where orthodromic routes were not possible because of the maritime morphology, canals between oceans were dug from the mid 19th century onwards. The Suez Canal was opened in 1869 and from the 1970’s it has been a major player in the growth of container transport. European flows will continue to pass by the Mediterranean and the Suez Canal, but today they can be impacted by the development of certain variables and by the risk that Europe will lose its central role in international flows by 2040. Consequently there is some doubt that the Suez Canal will continue to play its role in containerized transport flows, such as it is today. If we exclude the possibility of major geopolitical risks in the Middle East, a scenario which envisages a division of flows between several land and sea routes seems the most probable. After the rush to the Suez Canal, alternative itineraries will be the most effective way to avoid its saturation, to operate an improved targeting of routes, a reorganization of means and flows depending on the value of goods and the urgency of shipments; means which prioritize at certain times transit time and door to door service by land bridges and at other times the competitive rates of the southern ridge. But we also know that the operational responsibility for containerized freight belongs to the shipper or a logistic service provider or a vessel […]