The main deficiency of most current modeling approaches to transportation can be identified as neglect of the integration of existing geographical knowledge in regard to the ex ante transport/land use modeling approaches, with its focus on territorial dynamics and theory development. This paper addresses this aspect of the problem by introducing a theoretical and methodological framework for the analysis of the interrelationship between land uses. The analysis attempts to determine to what extent the functional land use in a city can be considered an ordered pattern. The order sought does not rely on purely spatial configurations, but on the correlation of transportation and land use. The first section of this paper focuses on theoretical considerations. It stresses the fact that conventional approaches do not apply in the present context. It then suggests an alternative based on areas of influence and measured in terms of level of attractance of land uses. The second describes a procedure based on this alternative following the remarkable contribution of Hanjoul, Beguin and Thill. An application of this procedure to the analysis of Shanghai is then examined. Finally, an evaluation of the strategies for optimizing the interrelationship between land uses is presented. The paper concludes with a possible research agenda.
It is well known that a pure privatization policy for the railway sector, as it has been implemented in the US, can solve financial problems, but the price which society has to pay for this policy is that the railway companies have to give up considerable parts of the transport market. As this contradicts the objectives of European transport policy, other ways must be found to increase the market efficiency of the railways without losing the benefits for the environment which stem from substituting car/air travel and road haulage by rail transport. One of these ways is to subdivide the railway system into (at least) two distinct organizations: a network company which is publically owned, controls the investments, and sells network capacity units at prices compatible with public goals, and a set of operation companies which operate on private accounts and maximize profits. The relationships between the government, the network, and the operation divisions may be formulated as principle agents problems. In the paper the decision levels of the publically controlled network cooperation, the operation companies, and the users are defined. The decision problems on each level are described in formal terms and the interfaces between these three levels are pointed out. Finally, some approaches to reorganize the railway system in Europe are described and lessons for the German case, where a new structure for the organization is crucially needed because of the new political situation after the German unification are derived.
In this paper an analytic method to evaluate technical and economic conditions of convenience for new high speed lines in guided transport systems, is described. In particular it answers the following main questions: what are the conditions to construct a new high speed line; what is the optimal operational speed of a new line; which is the better between two systems, differing in costs structure and quality of performance? It is shown that a modern railway, able to reach a speed up to 300 km/h, is in short-medium period better than contactless systems so far tested. In the last part of the paper a hypothesis of a new generation contactless system is outlined. A comparison with high speed railway shows that, from a theoretical point of view, this new system called "synthesis solution," could be in the future the real competitor of the railway.
Truck class rates are usually needed in strategic logistical planning, especially for facility location. Using point-to-point transport rates is exact, but for practical reasons it is often necessary to estimate them from distance. Two sources of rate estimating error are examined: (a) the error resulting from the linear approximation of rates from distances; and, (b) the error associated with estimating distances from shipment origin-destination coordinate points. Suggestions are made as to how the rate estimating error may be minimized.
This article investigates the macroscopic lane-changing characteristics on uncongested multilane freeways, focusing on the interrelations between the traffic conditions and the frequency (and fraction) of vehicles changing lanes. The data available for analyses were collected from two test sites using a time-elapsed video recorder. It has been found that traffic flow variables, such as the headway mean and variance, speed, and density ratios between neighboring lanes, are highly correlated with the fraction and frequency of vehicles changing lanes. The results of exploratory analyses are further examined with two generalized linear models. The logistic and Poisson regressions are used respectively for constructing the lane-changing fraction and frequency models. With maximum likelihood estimation (MLE) both models provide consistent information and achieve a reasonable goodness of fit.
The purpose of this article is to question the presumption that route guidance and information systems necessarily reduce traffic congestion, and to point out the need to consider the general equilibrium effects of information. A simple model of the morning rush hour is adopted in which commuters choose a departure time and one of two routes to work, the capacities of which are stochastic. While expected travel costs are reduced by perfectly informing all drivers about route capacities, this is not necessarily the case if imperfect information is provided. A heuristic explanation is that, absent tolls, congestion is an uninternalized externality. Information can cause drivers to change their departure times in such a way as to exacerbate congestion.
A modelling framework is developed to analyze the effect of in-vehicle real time information strategies on the performance of a congested traffic communing corridor. The framework consists of a special-purpose simulation component and a user decisions component that determines users' responses to the supplied information. The user decisions component is microscopic and determines individual commuters' route switching, at any node of the network, as a function of the supplied information. The traffic simulation component moves vehicles in bundles or macroparticles at the prevailing local speeds, as determined by macroscopic traffic relations. The framework allows the investigation of system performance under alternative behavioral response mechanisms, as well as under different information strategies. Results are presented for simulation experiments in a commuting corridor with a special network structure that simplifies the network computations. The results illustrate the effect of the fraction of users equipped with in-vehicle navigation systems on overall system performance. In addition, alternative assumptions on user response reflecting varying degrees of optimizing behavior are explored. The modelling framework is shown to provide a useful approach for addressing key questions of interest in the design of real time in-vehicle information system.
The operations of European railway companies are generally confined to the territory of one country. Each company incurs the cost of operations on its network. For international trains there are systems of physical compensation for vehicles and staff operating outside their home network. Revenues either go direct to each company involved, or, in the case of through international rates, are apportioned according to distance. This situation implies that for any decision on price and services agreement of all operators involved is necessary. Also, the apportionment of costs between operators is not in line with real cost structure. With further integration in the European community, and freer movement between Eastern and Western Europe, international transport will become more important, and railways will be at a disadvantage compared with other modes that can operate international services throughout. An organisation is proposed and illustrated with some examples, wherein separate commercial units are formed responsible for running and marketing an international rail service. Track, vehicles, and staff of national railway companiew may be used as now, but at a price to be agreed, and without the need for physical compensation.
Identification of the socioeconomic factors which affect the demand for buses, and the analysis of the use of the other transport modes by bus users are the two main objectives of this article. Work and school trips are highlighted as being very important trip purposes in Lagos metropolis by the multiple discriminant analysis model. It identifies mode of transport, distance, travel time, reliability, and the number of stops as significant mode choice variables. Multiple linear regression models for work and school trips identify mode of transport, transfort fare, travel time, annual income, and crew behaviour as significant variables in the choice of transport mode. These findings support the two alternative hypotheses of the study that the choice of bus is related to the individual perception of the quality of service of the different modes and that socioeconomic characteristics of the riders influence the patronage of buses. The attention of policy makers for the 22 transport corporations that operate inter-and intra-urban services in all the 21 states and the federal capital of Abuja in Nigeria is drawn to the importance of these variables for decisions.
This study develops a model that explains public transit ridership in Orange Country, California over quarterly periods during the 1974–1988 period. The model uses a Cobb-Douglas functional form and a Cochrane-Orcutt iterative procedure to measure the association between public transit ridership and the potential number of users, relative level of public transit service, relative price of public transit, seasonality, and external shocks. Relative measures of the explanatory variables are used to reduce the potential for multicollinearity and give greater confidence in the reliability of the estimated elasticities. The model is then used to prepare conditional quarterly forecasts for ridership in 1988 and unconditional quarterly forecasts during the 1989–1993 period.
The purpose of this paper is twofold. First, using data on Belgian railroad operations, we provide the first application of hedonic output aggregation to the railroad industry. Second, we compare the traditional homogeneous output approach with the use of these hedonic aggregates and carefully evaluate differences in estimates of input substitution possibilities, returns to scale, and productivity growth. It is found that ignoring the role of operating characteristics in cost analyses implies substantial bias in estimates of railroad technology.
