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This paper examines the problem of optimally locating a main facility with respect to located ancillary facilities when unit transportation costs between the main facility and ancillaries are known. Problems of location both in the planar and spatial states are examined, and an electrical analogue solution is proposed and verified. Solutions to problems with non-linear transportation cost functions are discussed and a worked example is included to illustrate the technique. [ABSTRACT FROM AUTHOR]

This paper is concerned with a "variable input output" system of inventory control in which both the inventory level and maintenance capacity are intimately connected to arrive at a minimum cost solution. The characteristic of the situation is the closed system formed by an organisation in which specific items which require periodic maintenance are at any time being used, reconditioned and stored.
A bus engine inventory network of a transport industry was studied and the optimum cost condition obtained for the total number of spare engines and maintenance channels. [ABSTRACT FROM AUTHOR]

The article presents a paper, which shows how to determine the optimal number and routings of containers used to move mail among several cities. This paper extends the above system to more than two cities, with different schedules on different days and with transfer of containers permitted throughout the system. A mathematical formulation is developed that can be readily solved by known linear programming techniques. Critical assumptions are (a) periodic demand patterns and linear transportation costs between each city-pair, and (b) constant fixed cost per container in the system. The optimization problem is transformed into a network flow linear program for which efficient solution methods are known. The researchers have investigated a system where containerized mail would be sent between two cities. The problem solved in reference was that of determining the best number of containers to be sent each day between the two cities, based on (a) the distribution of mail volumes going between the cities each day and (b) the costs for sending containers, full or empty, and for sending mail by other means in case of container shortage. Thus the original convex programming problem has been converted to an especially tractable type of linear program, namely the optimization of a network flow.

This paper investigates the welfare implication of changes in the transportation system in two special areas. The first is when the origin-destination demand for transportation may be assumed to be fixed and the second case is where, considering only work trips, origins may vary but destinations may not. A technique is described that could be used to forecast the new origin-destination demand resulting from a change in the transportation system. The technique also provides an appropriate measure of the welfare implications. A particular objective of the paper is to point out the pitfalls of using transportation (generalized) cost saving as a welfare measure whenever origin-destination demand may not be assumed fixed. In this situation it is shown that the welfare measure must take into consideration the benefit derived from the increased choice in available housing sites. [ABSTRACT FROM AUTHOR]

In the present paper the supporting data is presented to show that the number of persons that move between any two communities in the United States whose respective populations are P1 and P2 and which are separated by the shortest transportation distance, D, will be proportionate to the ratio, P1 * P2/D, subject to the effect of modifying factors. The first economy of living at the immediate source of raw materials saves the work of transporting the raw materials to the production-centers; the second economy of living in one big city where all production is done saves the work of transporting the goods to the consumers. Since the population cannot live both in a lot of communities scattered over the terrain and at the same time in a single big city, it is obvious that the above two economies are in conflict. The first economy of living at the immediate source of raw materials will act in the direction of making a large n-number of different communities of small P-sizes, if the terrain is reasonably homogeneous in its distribution of raw materials per unit of area in terms of cost in man-hours in procuring them.

In this paper, the author attempts to make a modest contribution to a subject which has suffered neglect by the transportation economists. I think that the subject is important and I regret the neglect. I am not certain that I can advance any facts or theories that are not already known to you, but I think that results will justify the effort if, by re exploring perhaps familiar ground in what I hope is an interesting and challenging way, I can arouse your interest sufficiently to give the matter further consideration. In any event, I take some comfort in a great statement by researcher D. Johnson, "People need not so much to be informed as to be reminded." In what follows I make three assumptions, which I bring to your attention early in my discussion in order to avoid possible confusion or misunderstanding. My first assumption is that our transportation system will continue to be a mixed one, that is, one owned and operated partly by government and partly by private enterprise. My second assumption is that the private sector will continue to be regulated by government substantially along present lines, because of the persistence of monopoly and other market imperfections. Third, I assume that travelers and shippers will continue to have legal freedom in their choice of means of transportation, even though government powerfully influences bases of such choice by provision of facilities and by regulation of rates and services. The pertinence and importance of these assumptions will become evident as my discussion proceeds.

Herbert Ashton's thoughtful paper on the time element in transportation offers a fundamental approach to the study of the time interval and cost incident to the movement of goods and persons. Studies of cost and quality of service generally have been related to the problems of regulation rather than to the evaluation and measurement of the economic impact of a more efficient performance of transportation service. In his discussion he poses three principal questions, if time, that is, speed, has economic significance in transportation service apart from other factors such as availability, cost, and dependability which can be separated out and measured independently, the economic significance of the time factor, and the economic importance of time. After assuming that the economic significance of time in transportation is implicit, he proceeds to recite the economic advantages of increased speed in terms of increased value of perishable and style goods, the extension of markets, faster turnover of stocks, reduced capital in goods in transit, and more stability of the distributive process.

This paper presents a simple graphical technique applicable to a wide variety of transportation problems involving a large number of production centers and market areas The assumption is made that transportation costs are monotonically increasing as one moves out from a given production center, but the rate of increase need not be constant or uniform in all directions [ABSTRACT FROM AUTHOR]

This article focuses on the transport costs and the location of firms. This paper follows the analytic approach of researchers A. Losch and J. Tinbergen, in so far as it explores some of the effects that the inclusion of transport cost might have on the neo-classical theory of the firm. In particular, our aim is to probe a little more deeply than hitherto into certain aspects of cost, price and firm density analysis, taking as our starting point an heroic set of assumptions regarding cost functions, consumer density and the like. Though the assumptions made are rather restrictive, we feel that our simple model has development potential along lines briefly suggested in the conclusion. The first section of the paper serves to illustrate the nature of some of the assumptions made. In second section to consider the least cost competitive case, where transport cost is the only cost borne by the firms. The least cost competitive case is the core of the paper, and in it we are concerned with specifying conditions that must hold when an optimum market area pattern prevails.

The paper considers the location of centers (e.g., plants, warehouses) on a network. Necessary conditions and sufficient conditions for optimal solutions to occur at nodes in the network are determined. The conditions include consideration of capacity constraints and the possibility that not all shipments are made via the `shortest route.' The cost functions may differ from arc to arc. A proof is given for the sufficiency of node locations in situations of multistage processing when transport costs are concave over each arc. Three sets of con conations under which it is necessary for an optimal solution to occur at a node are investigated. One set of conditions involves a production function characterization of the centers being located. [ABSTRACT FROM AUTHOR]

A method for estimating costs and benefits to commuters, over a period of time, is developed in this paper. The method will account for the variation of traffic volumes over the period of time considered. The cost structure of a transport mode is taken as a function of the volume of traffic on that mode. The distribution of traffic volumes is then used to measure the costs and benefits to the user and the state over a year. Commuters are divided into different social classes according to the value they place on the attributes of the different transport modes. Next the method is used to evaluate different road pricing schemes. Finally the road system is examined both as a public utility and as a public enterprise. [ABSTRACT FROM AUTHOR]

The problem treated is that of locating in centers (processing facilities) in a network, so as to minimize the total transportation cost associated with their use. On the assumption that all movements occur between a vertex and a center nearest it, HAKIMI has shown that only vertex locations for the centers need be considered. The present paper shows that this conclusion remains valid under alternative assumptions more appropriate for some applications. [ABSTRACT FROM AUTHOR]

Recent developments in aircraft technology will create greater airlift capabilities at lower costs. How will this increased capability be effectively utilized by the Department of Defense? Time-series extrapolations of air-cargo demand have been made in the past for the civil sector of our economy and similar projections have been proposed for military airlift planning. These proved less than successful when compared with actual tonnages generated. This paper will explore a different methodology for predicting airlift demand in the military establishment. Basic data, consisting of approximately 3.8 million commodities and millions of shipments recorded on magnetic automatic data processing tapes, are obtained from all DOD supply management activities. Two information files are established. One is a catalogue file reflecting the physical characteristics (weight, cube, price, etc.) of the commodities that influence total distribution costs of delivering the items to overseas destinations. The second is a demandfile containing the actual volume and traffic flow of the commodities. From these files, total distribution costs for air and surface movement are computed by a mathematical model for each commodity to determine the break-even air rate. The economically air-eligible commodities are then correlated with the volume and traffic flow to determine the elasticity of demand at various air ton-mile rates. Based on known operating costs of new aircraft, logical requirements for airlift can be established. At the same time, criteria for selecting air-eligible commodities are based on economic considerations, thus producing the least-cost method of supplying overseas activities. [ABSTRACT FROM AUTHOR]

This is the first of a series of simple mathematical models to explore the concept of decentralization. The primary focus is on pluralization as one of three aspects of decentralization. We derive expressions for cost and for net benefit as a function of the number of identical, uniformly dispersed facilities capable of servicing requests from sources that are uniformly distributed along a long, thin, geographical strip. The optimal, or cost-minimizing, number of such pluralized facili6es is computed. We also derive conditions in terms of the basic parameters, such as the number of requests per month, transport costs per unit time, etc., which favor pluralization over centralization. The models are also analyzed for the secondary benefits of redundancy for more dependable service and to smooth fluctuations in demand. We found that, on balance of all the factors, historical trends—particularly the trend toward more requests per unit time—favor pluralization. [ABSTRACT FROM AUTHOR]

Charges levied for the use of the existing and prospective competing transport facilities are far wide of the mark of representing marginal cost, as they often tend to be, It is this latter type of investment, designed to relieve congestion, with which this research paper is concerned. For purposes of economic analysis it is useful to distinguish at least six types of congested situations, though they are in fact often encountered in various combinations. These can be designated single interaction, multiple interaction, bottleneck, triggerneck, network and control, and general density. Multiple interaction tends to take place at higher levels of traffic density. In addition to the cost of delays, the cost of accidents constitute an often overlooked element in the costs of congestion. An important but not essential element in the strategic importance of pricing as a factor influencing investment decisions is the existence of variations in the value of time, not only for different persons at the same time, but for the same individual at different times.

Measures the increase in marginal transportation costs paid for by final consumers due to inefficient flow pattern created by restrictions on trade in natural gas. Comparison of the actual distribution of gas to a hypothetical free trade distribution; Estimation of the regional gains and losses among purchasers and producers; Calculation of the distribution of flows using a linear programming model.

The purpose of this paper is, first, to construct a simple model of a city (a metropolitan area) and to calculate in this model how transportation costs vary with city size and, second, to try to examine whether the available data conform to what is expected according to that model. The model is a simplified version of the models that were used in the recent literature in this area Simplifying the basic assumptions makes the model more manageable, which, in turn, enables us to calculate explicitly magnitudes that were not calculated in the more complicated and general models. [ABSTRACT FROM AUTHOR]

This paper reports the results of a study of the relationship between the cost function for providing urban bus service, some of the technological relationships underlying the cost function, and the environmental setting in which the bus firm operates. It attempts to show that the environmental setting is relevant and that costs of urban bus operation vary across cities in ways that cannot be entirely accounted for by factor price or output differences. [ABSTRACT FROM AUTHOR]

The article discusses the literature of railway rate theory in the United States. The thing which the theory of railway rates had to explain was the lack of uniformity in charges for services performed at approximately equal costs. The practice of adjusting rates to the conditions of demand manifested itself in a number of ways. It resulted in the practice of classifying freight, and of granting exceptional or special rates on commodities that required particularly low rates. The first criticism of the joint-cost theory is based on the contention that there must be two or more products or services produced together before joint costs can appear, and that a railway provides a single homogeneous commodity, namely, transport. It can easily be seen that the demand for the transport of one commodity is largely independent of the price at which the transport of other commodities is sold. A considerable degree of differentiation is necessary to utilize existing plant. The extra traffic occasions an extra capital cost, but still enables other portions of the plant to be utilized more nearly to capacity without additional expense.

Cost analysis in transportation has been found to contribute in greater or less measure to the solution of a wide variety of problems relating to transportation rates and services. A brief resume both of the types of cases in which costs have been helpful and the issues involved in such cases may serve at this point to focus attention on the general nature of the problems with which the analyst must cope. Probably one of the simplest uses of cost is that involved in the determination of whether or not a particular train or bus schedule should be continued in service. Cost analysis is frequently involved in abandonment proceedings, a fundamental question being whether the cost of hauling that traffic which originates or terminates on the line to be abandoned and which would be lost to the carrier if the line were abandoned, exceeds the system gross revenues earned from such traffic. Again, on traffic handled over the lines of two or more carriers, questions as to the division of the revenues among the participating roads may call for studies to show the relative expense, line-haul and terminal, which each road incurs in performing its portion of the haul.

Since transportation is a means to an end, the demand for it is a derived demand. This fact has significance because the nature of the demand for transportation is conditioned by trading operations which develop as a result of underlying economic factors at any given time. The nature of the demand for transportation is derived from the nature of the commercial transactions involving transport services. In some respects the causal connection works both ways, the nature of the transportation services available affect the character of commercial transactions carried on. The purpose of the present analysis is to consider whether time has economic significance apart from the other factors such as availability, dependability, and cost which can be separated out and measured independently. The answer to this question must include an explanation of the reason why the speed of transport has economic significance, which involves an analysis of the nature of the demand for it. It will be necessary, also, to explain how the economic importance of time or speed is made evident.

In recent years, passenger volume on American trains has declined substantially, resulting in large passenger deficits. If railroads have higher costs than other transportation modes, they must incur deficits to be price-competitive, these deficits induce fare increases, cutting rail volume. But costs do not tell the whole story: the greater speed and convenience of other modes would cause an inevitable contraction of rail patronage in some markets, even if the railroads were the low-cost mode. The first section considers in some detail the two previously mentioned cost studies, it appears from this that a different approach to passenger train cost estimation would be fruitful. In the second section, some new cost results are reported for trains, buses, planes, and autos. The third section reexamines the decline of the passenger train in the light of these new cost results. The implications of these results for the future of the passenger train, and also for public policy, are considered in the final section.

Focuses on the transport costs and choice of a tariff valuation base. Impact of free on board base on the trade; Measurement of the inland freight costs; Aspects of the cost, insurance and freight distortion.