Current air traffic control rules require that the fixed distance separations between aircraft operations be maintained on a runway. The runway capacity is inversely proportional to the time headway between operations. In such a case that the distance separation is settled, the time headway could be reduced by increasing the approach speed of aircraft. However, as the approach speeds increase, the runway occupancy times of landing aircraft will increase, and consequently, the runway capacity will decrease. In order to maximize the runway capacity under the above-mentioned conditions, in this paper, a method is proposed to match approach speeds of aircraft with distance separations by using the mathematical optimization techniques. Based on the numerical results obtained, the factors that restrict the further increase of runway capacity are made evident

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Comparative static analysis deals with the study of how, in a given economic model, endogenous variables react to given changes in exogenous variables or parameters. Although the method has been applied in various fields in socio-economic systems, it has well-known drawbacks in coping with taste changes in the sense that taste changes will usually cause shifts in effective values of variables. In this paper, we try to describe endogenous taste changes by a form of Lie transformations and present a general methodology of comparative static analysis for dealing with taste changes. We show applicability of our new methodology by demonstrating two generic examples, that is retaillocation model and residential location model.

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By use of sociometric indices from graph theory, the paper presents three mathematical models for measuring performance levels of highway networks.
The first model, called “status index with respect to section” or SIS, is intended to indicate explicitly the performance level of a particular section (link) between two major crossings (nodes), relative to the aggregate performance levels of the entire network, of which the section is part.
The second model, called “status index with respect to route” or SIR, aims to indicate explicitly the performance level of a particular route, relative to the aggregate performance levels of the entire network, in which the route is a chain of particular sections. The third one, called “status index with respect to its role in route formation or “SIRF”, explicitly indicates the importance of a particular section, relative to the entire network, measured in terms of the increment in the shortest distance for a given OD pair when the section is removed.
With a case study performed for the highway network in the eastern part of Tottori prefecture, it is shown that the proposed models will appropriately serve the intended purposes when applied in practice.

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In this paper, simple analytical expressions for predicting percentile and equivalent sound level (L_x and L_Aeq, T) propagating over various ground surfaces from a stationary traffic flow are presented. Particularly on a straight motorway in a flat site, where noise radiates from freely flowing traffic whose headway is subject to Exponential distribution, simple predictive equations for calculating L_x and L_{Aeq, T} are functions of hourly volume, mean speed, proportion of trucks, integration values of weighting function corresponding to sound propagation characteristics and so on. And validation studies have indicated that percentile and equivalent sound levels were calculated accurately from presented simple equations.

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The way through which people conceive images of their living condition is scrutinized in this paper in order to develop an evaluation method of the environment. To find the cognitive structure, the authors employ two kinds of association tests. The free association test is employed to show what aspect of the environment is of prime interest of local residents. The frequency of controlled association between words concerning living conditions is examined to uncover the cognitive structure of the environment. Cluster analysis methods and a directed graph representation are utilized for the analyses.

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This report describes a mathematical evaluation method of merging traffic on a center ramp terminal which is often designed for urban expressways. In order to make the evaluation, the merging probability on the center ramp terminal was compared with that of an usual side ramp terminal. Traffic flow on the both ramp terminals was recorded by using TV camera. The traffic volume and speed as well as the gap distribution were measured and the acceptable gap size was determined. Then the merging probability was computed based on the gap distribution and the acceptable gap for both the center ramp and the side ramp making use of probability theory. It is found that the merging probability of the center ramp wass about 10% smaller than that of side ramp terminal. It is suggested that careful attention should be given to the design and the operation of center ramps.

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In this paper, we discuss the resource allocation for the construction scheduling, i. e. we decide the number of the resources and the scheduling each activities with the cost to minimize by the heuristic approach. The heuristic approach repeat to calculate till objective completion date, which is scheduling problem by PERT and date reduction problem by CPM.
In this case, we consider the cost which is to carry in onsite and to carry out from onsite of all the resources. We applied the heuristic approach to the caisson type breakwater construction scheduling, and obtained satisfactory results.

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The conventional traffic assignment models presented up to now aim at allocating a set of OD flows of an entire day to a traffic network. In this paper we propose two type of time-of-day traffic assignment models which can describe real traffic flows by hour of the day over a network. Both of the models require some modification of demand flows among the adjacent hours for the conservation law of flows. In the first model, which we call link-flow modification method, the modification is done based on link flows, and in the second model, which we call OD-flow modification method, the modification is done based on OD flows. It is shown that the latter method can be formulated as the Beckmann-type user equilibrium assignment problem. Two models presented here are also compared through the application to the real traffic network.

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This paper discusses the optimal road pricing, which minimizes the total travel time, under Stochastic User Equilibrium (SUE) in the general transportation network. We analyse the structure of the problem formulated as a bilevel programming, using the conception of duality. As the result, we learn that the system optimum flow pattern can be attained in an arbitrary network by setting an appropriate toll pattern and the general solution has a form extending the conventional marginal cost pricing to the stochastic user behavior. Moreover, the uniqueness of the optimum link toll is proved in the case of logit-based SUE.

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The purpose of this paper is to develop a method to make rational land use plans, based on computer aided data processing. First, concept of land use planning is defined from the viewpoint of optimization process in order to give logical consistency to land use planning process. Second, a methodology is proposed which can realize logically consistent land use planning based on the above mentioned concept of optimizing process. Then, a computer aided land use planning system is developed which is effective for not only city-wide land use planning such as land use zoning but also microscopic land use planning such as land readjustment.

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