This research proposes the dynamic equilibrium assignment on an over-saturated transportation network with a one-to-many origin-destination pattern. The proposed model satisfies the FIFO discipline of traffic flow and explicitly deals with effect of queues growing on any links in a network. We first show that the problem can be decomposed with respect to the traveler's starting time from the single origin based on the fundamental properties derived from the dynamic user equilibrium principle. Then, it is shown that the each decomposed problem is considered as a fixed point problem, which is a natural extension of the conventional static assignment problem. The solution is proven to exist, though the uniqueness is not generally guaranteed. Furthermore, we propose an solution algorithm which does not require a path enumeration. Finally, we show that the above conclusions are also applicable to the case of many-to-one OD pattern.

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The characteristics of traffic density on the time-distance space is analyzed using hydrodynamic theory. By examining a density distribution at an isolated signalized intersection, characteristics of the differential equation which determines a density behavior is investigated. The deferential equation is solved numerically by replacing waves which are distributed continuously on the time-distance space by discrete shock waves (quasi-shock waves). The model that has been developed by using the concept of quasi-shock waves is generalized to analyze road networks. The developed model can consider a demand variation along time and location and traffic behavior at branching points.

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This study analyses effects of heavy vehicles on uncongested traffic flow on intercity motorways. First, several definitions of the PCE (Passenger Car Equivalence) are reviewed and the problems on PCE are pointed out through the estimation of PCE values by speed levels at 43 locations on the Tomei expressway using traffic detector data. Second, to evaluate effects of heavy vehicles, the study proposes a 3-dimensional regression of flow, speed, and percentage of heavy vehicles as a function of the road alignment as well as visibility without introducing PCE.

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Sensitivity analysis and risk analysis have been used for the evaluation of uncertainty of transportation projects. Application of these analyses to the real projects has several difficulties such as difficulty of estimation of occurring probability of events. Considering the transportation project as an investment and setting an option on it, it is possible to construct an index which includes the information on uncertainty of transportation projects. Based on this consideration, this paper proposes the project risk index which is calculated from the values used in usual feasibility study, and analyzes the several characteristics of the index.

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Many authors have tried to assess the benefits of public works, including transport improvements, through the property value method. As the method is valid only when the small-open assumption is fulfilled, it is quite important to confirm the openness of the city when we ask for a fair cost-sharing on the ground of value captures. In the paper, we first review the results from a NUE city to clarify how the benefits from the reduced travel costs are theoretically absorbed by respective agents. The empirical study is conducted on Fukuoka city where the subways were constructed in early 80's. We employ a land value function to assess the portions of increases in land values which are attributable to the subways. Comparing those empirical results with the theoretical ones, we evaluate the openness of the study area, and thus, the validity of the property value method in local cities.

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There are many theoretical studies on the impacts of infrastructure development. However, most of them are in the framework of neoclassical economics, which cannot deal with disequilibrium states of economy.
This paper attempts at a model analysis that shows the characteristic of the impacts under Keynesian disequilibrium economy, comparing of those under Walrasian equilibrium. As main results, investment for the infrastructure causes different effects on national economy under Keynesian disequilibrium from those under Walrasian equilibrium. Furthermore, such impacts are evaluated from the point of social welfare. It is shown as a result that infrastructure projects might be unfavorable in a certain case because they lead to the decrease of social welfare.

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A rectangular inter-regional input-output model is discussed in this paper which is expected to realize more accurate prediction of inter-regional freight flow than the others, since it deals the inter-industry transaction by commodity. A rectangular inter-regional input-output table is determined by using a part of the national rectangular input-output table, i. e. V table, and the inter-regional input-output tables. A rectangular type of the inter-regional freight flow table, on the other hand, is prepared by using the freight flow CENSUS in 1990. The metric ton based inter-regional freight flow is, then converted to the value based trade table with the commodity prices. The purpose of the paper is an evaluation of the accuracy of the rectangular inter-regional input-output table comparing with the real freight flow. The result showed that there are significant mismatches of transaction, however, the method can still be used for the inter-regional freight flow forecasting.

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Intraregional input-output analysis is widely used for measuring economic impacts which are derived from public investment. But in the usual intraregional input-output analysis, the Bounding-back effects that is a kind of interregional repercussion effects have been ignored since the interregional trades are given externally.
This paper presents simple method which could measure interregional Bounding-back effects by using intraregional input-output table. Using this method within the context of intraregional analysis is equivalent to interregional input-output anaylsis.

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A method for establishing control networks or deformation fields from sequential geodetic measurements is developed. The method is based on the use of the free network solution which is obtined from the results of adjustment by the method of condition equations. The conditions applied in this paper are as follows: (1) Repeated geodetic measurements are carried out at different epochs to determine the coordinates of the points which make up a network. (2) the network of the one epoch should be fitted in that of the other epoch. (3) the weight given at each point for fitting should be arbitrary. Applications of the method are outlined and illustrated by elementary mumerical examples.

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This paper aims to develop an optimization model for railway profile design. First, the methods to decide the positions where gradients change, that use the quadratic basic spline (B-spline) functions, are discussed by considering the charateristics of the earth surface line. Then we apply the linear B-spline functions to behave the railway profile design line and simulate the traditional process of the railway profile design by considering the characteristics of the B-spline base functions. Further, the applicability of proposed model is tested by a case study based on the data of P. R. China.

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Logit model is the simplest and best-known probability choice model that is derived within the framework of the Random utility theory. Since the standard logit model treats the total consumption level as given, there remains the problem of dealing with the generated transport demand. This study proposes a different derivation of the logit type of demand model that is a mathematical resemblance of the logit model in the context of consumer behavior theory. Without loss of generality, the model enables us to explicitly analyze the generated demand and is further used to study the share model and to provide a likely different technique to forecast the absolute quantities of the travel as well as of the other goods. Moreover, a gravity model can also be derived. Finally, the consistency of the proposed model is verified by the derivation of the consistent direct utility functions.

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