bluuebunny/crossref_metadata_2025 huggingface dataset:
Bibliographic Section
Authors: Brownstone David , Daughety Andrew F. , Jara-Díaz Sergio R.
Published: October 2008

Handbook of Econometrics, Vols. 1 and 2, edited by Zvi Griliches and Michael D. Intriligator. Handbooks in Economics Series, Book 2. New York, Amsterdam and Oxford: North Holland; distributed in U.S. and Canada by Elsevier Science, New York, 1983, 1984—reviewed by David Brownstone.

Deregulating the Airlines, by Elizabeth E. Bailey, David R. Graham and Daniel P. Kaplan, MIT Press, Cambridge, Mass., 1985, 343 pp—reviewed by Andrew F. Daughety.

Transport System Optimization and Pricing, by Jan Owen Jansson. John Wiley & Sons, New York, 1984, 280 pp—reviewed by Sergio R. Jara-Díaz.
The Location of Interacting Hub Facilities
Authors: O'Kelly Morton E.
Published: October 2008

Hubs are central facilities which act as switching points in networks connecting a set of interacting nodes. This paper develops several location models for hubs. The one-hub siting problem is equivalent to a Weber least cost location model. An empirical example demonstrates the relevance of this model for an understanding of contemporary express delivery networks. A new model describing the location of two hubs in a plane yields several interesting pairs of hub location under different assumptions about scale effects on the interfacility linkage: generally as these scale effects increase the locations of the hubs move apart.
Dynamic Model of Peak Period Traffic Congestion with Elastic Arrival Rates
Authors: Ben-Akiva Moshe , de Palma Andre , Kanaroglou Pavlos
Published: October 2008

The paper develops a dynamic model of peak period traffic congestion that considers a limited number of bottlenecks. The model predicts the temporal distribution of traffic volumes with an elastic demand model. In response to changes in the traffic conditions travelers can switch to a different mode, divert to an alternate route, or shift the trip forward or backward in time to avoid a long delay. A simple example would be the case of two parallel routes with travelers jointly selecting route and departure time. The choice of route and mode are dependent on travel times and travel costs. The choice of departure time is based on the trade-off between travel time and schedule delay which is the difference between the actual and the desired arrival times. The delays at the bottlenecks are modeled with a deterministic queueing model that determines waiting time as a function of the length of the queue at the time of arrival at the bottleneck. The day to day adjustment of the distribution of traffic is derived from a dynamic Markovian model. The model is used to perform simulation experiments. The results demonstrate the response of the traffic conditions at the bottlenecks to a change in the system. The model is used to analyze the impacts of alternative pricing policies and preferential treatment of high occupancy vehicles.
An Analytic Assessment of Subsidies to Bus Services
Authors: Bly P. H. , Oldfield R. H.
Published: October 2008

A simple mathematical model has been constructed of a bus service, in a way which allows the requirements for maximum benefit, and the rate of return on subsidy, to be solved analytically. Although the model is very aggregate, it permits categorization of different passenger types and the inclusion of external (i.e., nonpassenger) benefits, and incorporates the effects of changing bus occupancy on speed, and therefore on operating cost, and on average passenger waiting time (because some buses may be full). The physical meaning of the rather complicated equations which result is explained and, where necessary, the assumptions are simplified to illustrate the often very simple trade-off between service cost and passenger benefit which occurs at maximum benefit. Equations are derived which describe how patronage, fares and the number of bus-kilometers operated change with the amount of subsidy provided, and how average bus occupancy, the elasticities of demand with respect to fares and service, and the amount of subsidy per additional passenger depend on the level of subsidy. A numerical example, typical of urban bus services in the United Kingdom, illustrates the model and shows the relative sizes of the contributions to cost or benefit made by the different components. The results of the model agree well with a cost/benefit assessment from a more sophisticated computer model, and the implications of using subsidy to reduce fares or improve service in a suboptimal way are investigated.
Fleet Sizing under Production Cycles and Uncertain Travel Times
Authors: Turnquist Mark A. , Jordan William C.
Published: October 2008

This paper develops a model for sizing a fleet of containers used to ship parts from a single manufacturing plant to a group of assembly plants. Parts are produced in a deterministic production cycle, but container travel times are stochastic. Based on results for an infinite-channel service process, equations are developed relating fleet size to the probability of a container shortage. An example illustrates this fleet size-shortage probability trade-off and shows the impact of uncertainty level and the number of plants on fleet size.
Rail Line Length in an Urban Transportation Corridor
Authors: Wirasinghe S. C. , Seneviratne P. N.
Published: October 2008

The length of a rail line that will minimize total transportation (user and operator) costs, and the threshold demand necessary to ensure that the resulting length of the rail line is nonzero are investigated for an urban transportation corridor. A density of demand for travel to the central business district (CBD) represented by a general function P(x) passengers per unit length of the corridor where x is the distance from the CBD is considered. The line-cost as a function of x, the costs of the rail fleet, rail and bus operating costs and passenger time costs are also considered in the formulation. The fleet size is formulated considering the peaking of demand relative to time. When the line cost is nonuniform there could be several line lengths at which the total transportation cost is minimized or even maximized locally. When the line cost per unit length is uniform, a minimum transport cost rail line of nonzero length exists only if the net gain in travel time and operating cost of transporting the total ridership a unit distance by rail, when compared to bus, exceeds the marginal line and fleet costs per unit length. In either case, the minimum transport cost rail line length can be determined easily. The effects on the line length of shifts in demand are investigated. Closed-form solutions for the line length are obtained for the cases of sectorial and rectangular corridor-sheds with uniformly distributed demand per unit area.
A Local Improvement Heuristic for the Design of Less-than-Truckload Motor Carrier Networks
Authors: Powell Warren B.
Published: October 2008

The load planning problem for less-than-truckload motor carriers is formulated as a fixed charge network design problem where level of service constraints are represented heuristically through a set of minimum frequencies on links. If direct service is offered between two terminals, it is required to do so at a given minimum frequency, implying not only a fixed charge from adding direct service but also a link cost function that is then flat until the flow on the link exceeds the minimum frequency. A local improvement heuristic is proposed which adds and drops links to and from the network in an intelligent sequence. After each change, the routing of the freight over the network is approximately reoptimized. Empty balancing of equipment is also handled explicitly. The approach has been applied successfully to a network with over 300 terminals; numerical tests on a 140 terminal network are reported.
Bibliographic Section
Authors: Horowitz Joel L.
Published: October 2008

Discrete Choice Analysis: Theory and Application to Travel Demand, by Moshe Ben-Akiva and Steven R. Lerman, The MIT Press, Cambridge, Mass., 1985, 390 pp. + xx—reviewed by Joel L. Horowitz.
Acceleration Profile Models for Vehicles in Road Traffic
Authors: Akcelik R. , Biggs D. C.
Published: October 2008

Three new models of acceleration profile (a two-term sinusoidal, a three-term sinusoidal, and a polynomial model) are described. These models yield the S-shaped speed-time trace indicated by data from driving in real-life traffic conditions, satisfy the realistic conditions of zero jerk (except the two-term sinusoidal model) and zero acceleration at the start and end of the acceleration, and allow for the position and the value of the maximum acceleration to vary for a given average acceleration rate. A comparative evaluation of these three models and the previously known constant and linear-decreasing acceleration models is reported. The evaluation criteria are distance traveled and fuel consumed during acceleration. The performances of the five models are compared under three sets of conditions: acceleration time and distance known, time known but distance unknown, and both time and distance unknown. The comparisons are made separately for central business district (CBD), other urban and nonurban traffic conditions. The polynomial model has been found to be the best overall for predicting acceleration distance and fuel consumption. Similar results have been found for deceleration profiles. Dependence of fuel consumption on acceleration rate and profile is also discussed. Suggestions for further work using the results of this report are included.
Bibliographic Section
Authors: Psaraftis Harilaos N. , Rogerson Peter A. , Schwing Richard C.
Published: October 2008

The Traveling Salesman Problem: A Guided Tour of Combinatorial Optimization, by E. L. Lawler, J. K. Lenstra, A. H. G. Rinnooy Kan and D. B. Shmoys (eds.), John Wiley & Sons, New York, 1985—reviewed by Harilaos N. Psaraftis.

Urban Evolution: Studies in the Mathematical Ecology of Cities, by Dimitrios S. Dendrinos with Henry Mullally. Oxford University Press, Oxford, 184 pp—reviewed by Peter A. Rogerson.

Risk and Freedom? The Record of Road Safety Regulation, by John G. U. Adams, Transport Publishing Projects, Cardiff, Great Britain, 1985, 202 pp—reviewed by Richard C. Schwing.
The Morning Commute for Nonidentical Travelers
Authors: Newell Gordon F.
Published: October 2008

In previous theories of the morning rush hour, travelers with different work starting times are assumed to attach certain values to queueing delay and schedule delay (deviations from their work starting times), the same values for all travelers. The goal was to establish and evaluate a stable assignment of trip starting times such that no individual traveler can find a more desirable time than the one assigned. This theory is extended here to situations in which different travelers may attach different values to these delays. For a certain class of cost models it is shown that there is still a stable assignment but it is dictated by only a certain fraction of travelers who are most willing to be early or late for work. Other travelers will choose to be at work on time. The queueing pattern is significantly different from that of the previous theories.
On Boundedly Rational User Equilibrium in Transportation Systems
Authors: Mahmassani Hani S. , Chang Gang-Len
Published: October 2008

A boundedly rational user equilibrium (BRUE) is achieved in a transportation system when all users are satisfied with their current travel choices. The theoretical and behavioral background for such a state is given in this paper. The properties of a BRUE in an idealized commuting system with a single bottleneck are investigated, and conditions for the existence of a BRUE are given. More general situations with multiple bottlenecks are also addressed. In general, BRUE flows are not unique, raising methodological and practical issues in flow prediction.
Modeling Distribution Problems with Time Windows: Part I
Authors: Daganzo Carlos F.
Published: October 2008

This paper shows how distribution problems with delivery time constraints can be modeled approximately with just a few variables. Its objective is neither to develop a scheduling algorithm nor an exact predictive method; rather, it is to illustrate some trade-offs and principles that can be used for planning and algorithm development. A workday is divided into time periods. Time windows are modeled by specifying the period in which a vehicle should visit each customer. (The companion paper explores scenarios where many customers do not specify a time window, and thus, it is advantageous not to allocate all the customers to periods.) Travel distance expressions are provided for a “cluster-first, route-second” strategy, similar to some routing methods currently in use. Travel distance expressions are also provided for refinements of the strategy, including one in which tours are systematically staggered, overlapping. The consequent reductions in travel distance can be quite significant. We suggest here that more attention should be paid to the clustering part of algorithm construction, and point to ways in which the customers served by one vehicle should be selected.
The Stochastic Queue p-Median Problem
Authors: Berman O. , Larson R. C. , Parkan C.
Published: October 2008

This paper derives two easily programmable heuristic procedures for locating p mobile service units on a network in the presence of queueing-like congestion. Both heuristics take advantage of the Hypercube model, a location model for a single service unit, and a normalizing technique known as mean service time calibration. Heuristic 1 uses the 1-median problem, whereas heuristic 2 uses the stochastic queue median. A simulation model is employed to validate the results and compare the heuristics.
Bibliographic Section
Authors: Kitamura Ryuichi , Ardekani Siamak A.
Published: October 2008

Behavioural Research for Transport Policy, VNU Science Press, Utrecht, The Netherlands, 1985, 490 pp—reviewed by Ryuichi Kitamura.

Introduction to Transportation Systems, Lonnie E. Haefner, CBS College Publishing, New York, 1986, viii, 488 pp—reviewed by Siamak A. Ardekani.
Equilibrium Decomposed Optimization: A Heuristic for the Continuous Equilibrium Network Design Problem
Authors: Suwansirikul Chaisak , Friesz Terry L. , Tobin Roger L.
Published: October 2008

For applications of realistic size, both the discrete and continuous versions of the equilibrium network design problem are too computationally intensive to be solved exactly with the algorithms proposed to date. This intractibility owes to Braess' paradox which makes it necessary to constrain the flow pattern to be a noncooperative Nash or user equilibrium. This paper suggests a new heuristic for finding an approximate solution to the continuous equilibrium network design problem. Numerical tests are reported which indicate that, for networks with significant congestion, the heuristic is markedly more efficient than the Hooke-Jeeves algorithm which has been employed previously. The efficiency of the heuristic results from decomposition of the original problem into a set of interacting optimization subproblems. This decomposition is such that, at each iteration of the algorithm, only one user equilibrium needs to be calculated in order to update the improvement variables of all arcs of the network. This contrasts sharply with the Hooke-Jeeves algorithm which can require that a new user equilibrium be calculated each time an individual arc improvement variable is updated.
The Tug Fleet Size Problem for Barge Line Operations: A Polynomial Algorithm
Authors: Jaikumar Ramchandran , Solomon Marius M.
Published: October 2008

In this paper the problem of minimizing the number of tugs required to transport a given number of barges between different ports in a river system is considered. The problem has traditionally been viewed as a vehicle routing problem and thus routing heuristics have been used. Advantage is taken of the feature that transfer time at ports is negligible, and the problem is modeled differently. A one-pass algorithm is developed which solves the problem in O(n) time. Extensions are made dealing with general river system structures and stochasticity in the demand pattern.
Survey Paper—Time Window Constrained Routing and Scheduling Problems
Authors: Solomon Marius M. , Desrosiers Jacques
Published: October 2008

We have witnessed recently the development of a fast growing body of research focused on vehicle routing and scheduling problem structures with time window constraints. It is the aim of this paper to survey the significant advances made for the following classes of routing problems with time windows: the single and multiple traveling salesman problem, the shortest path problem, the minimum spanning tree problem, the generic vehicle routing problem, the pickup and delivery problem including the dial-a-ride problem, the multiperiod vehicle routing problem and the shoreline problem. Having surveyed the state-of-the-art in this area, we then offer some perspectives on future research.
Conditional Minisum and Minimax Location-Allocation Problems in Euclidean Space
Authors: Chen Reuven
Published: October 2008

The problems of minimax and minisum location-allocation in two-dimensional Euclidean space, where some fixed service centers already exist in the area in question, are treated. The method utilized is an extension to a previously reported algorithm for the solution of the unconditional problem and yields good local minima. In the minisum problem this is at the moment the only feasible way to obtain any solutions. In the minimax case, a method for finding optimal solutions has been developed in parallel. However, the latter can yield results only to problems of limited size. A possible combination of the two methods is suggested.
A Model and Solution Algorithm for Optimal Routing of a Time-Chartered Containership
Authors: Rana Krishan , Vickson R. G.
Published: October 2008

We formulate a mathematical programming model for optimally routing a chartered container ship. Our model helps in evaluating whether a container ship should be chartered or not. The model calculates the optimal sequence of port calls, the number of containers transported between port pairs, and the number of trips the ship makes in the chartered period. A specialized algorithm is developed to solve the integer network subprograms which determine the sequence of port calls. Our algorithm, which solves an integer program optimally, is quite efficient. Comparison of computational results with a Lagrangean Relaxation method and an embedded dynamic program are also presented.
Private Market Participation in Urban Mass Transportation: Application of Computable Equilibrium Models of Network Competition
Authors: Harker Patrick T.
Published: October 2008

Urban mass transportation is a major recipient of local, state and federal capital and operating subsidies. In this era of increasing pressure to reduce budget deficits at all levels of government comes the call to return part of the urban mass transit industry to the private sector. This paper presents the theory and application of a computable equilibrium model of urban mass transportation which is designed to address the issues of sustainability and distributional equity in this market. This model also serves as an illustration of how computable equilibrium models can be employed in the analysis of network-based competition. A series of examples from the Philadelphia region are presented to illustrate the model's potential as a policy analysis tool and to shed some light on the efficiency versus distributional equity debate which is currently underway in the transportation/public policy community.
Solving a Family of Multi-Depot Vehicle Routing and Location-Routing Problems
Authors: Laporte Gilbert , Nobert Yves , Taillefer Serge
Published: October 2008

This paper examines a class of asymmetrical multi-depot vehicle routing problems and location-routing problems, under capacity or maximum cost restrictions. By using an appropriate graph representation, and then a graph extension, the problems are transformed into equivalent constrained assignment problems. Optimal solutions are then found by means of a branch and bound tree. Problems involving up to 80 nodes can be solved without difficulty.
An Optimal Scheduling System for the Welland Canal
Authors: Petersen E. R. , Taylor A. J.
Published: October 2008

The problem of real time scheduling of vessels through the Welland Canal is discussed. A mathematical programming scheduling algorithm is presented. The problem is formulated as a master schedule selection problem and a schedule evaluation subproblem. The schedule evaluation subproblem is a linear programming model, which, due to special structure, can be solved using an efficient dynamic programming algorithm. The schedule selection algorithm is a heuristic that employs optimal dynamic programming submodels for scheduling the individual locks. Sensitivity information from the schedule evaluation model is used in a greedy type of algorithm to fine tune the schedule. An example of a schedule for the Welland Canal is presented.
The Prevalence of Paradoxes in Transportation Equilibrium Problems
Authors: Steinberg Richard , Stone Richard E.
Published: October 2008

Consider a congested transportation network, where the cost along each arc is affine, i.e., consists of a fixed cost plus a variable cost proportional to the flow. We present a new paradox demonstrating that, in a congested transportation network, a sufficiently high increase in the congestion effect along a route can result in the abandonment of a different route having the same origin and destination while the original route continues to be used. We also present a method for testing whether or not the paradox will occur in an arbitrary transportation network by viewing the question as a parametric linear complementarity problem. The new paradox is contrasted with Braess' paradox, and intuition is developed to explain the prevalence of such paradoxes in transportation equilibrium problems.
A Column Generation Approach to the Urban Transit Crew Scheduling Problem
Authors: Desrochers Martin , Soumis François
Published: October 2008

The urban transit crew scheduling problem arises in mass transit organizations which have to create minimal cost bus driver schedules respecting both the collective agreement with labor unions and the bus schedule. We propose a column generation approach to solve the transit crew scheduling problem. The column generation approach decomposes the problem into two parts. The set covering problem chooses a schedule from already known feasible workdays. The second subproblem is a shortest path problem with resource constraints and is used to propose new feasible workdays to improve the current solution of the set covering problem. The approach has been successfully tested on real-life problems.
Multicriteria Model to Determine Flight Frequencies on an Airline Network under Competitive Conditions
Authors: Teodorović Dušan , Krčmar-Nožić Emina
Published: October 2008

A multicriteria model is developed to determine flight frequencies on a route network when there is competition. In determining flight frequencies, the focus is placed on maximizing profit, maximizing the number of passengers flown and minimizing the total passenger schedule delay. The problem of determining flight frequencies on a route network is a large combinatorial problem whose optimal solution is difficult to find, and a heuristic approach must therefore be used to solve it. The nonlinear integer problem in the paper is solved using the Monte Carlo technique of randomly generating several solutions and choosing the best among them.
Locating Facilities on the Manhattan Metric with Arbitrarily Shaped Barriers and Convex Forbidden Regions
Authors: Batta Rajan , Ghose Anjan , Palekar Udatta S.
Published: October 2008

This paper considers two planar facility location problems while employing the Manhattan travel metric. We first consider the p-median problem in the presence of arbitrarily shaped barriers and convex forbidden regions. For this problem we establish that the search for an optimal solution can be restricted to a finite set of easily identifiable points. Next, we consider the stochastic queue median problem in the presence of arbitrarily shaped barriers. A procedure to obtain a global optimum solution for this problem is established. The results of the paper are illustrated via numerical examples. Finally, we comment on a connection between network location problems and planar location problems which use the Manhattan travel metric.
Gap-Acceptance and Empiricism in Capacity Prediction
Authors: Kimber R. M.
Published: October 2008

The paper compares the results of extensive measurements of the capacity of nonpriority traffic streams at major/minor junctions and roundabouts with the predictions of models based on gap-acceptance theory. There are significant differences in the form of the relation between the capacity and the traffic flows in the priority streams. The simple gap-acceptance models are poor predictors of the capacity in the United Kingdom, for they seriously overpredict at low values of priority flow and underpredict at high values. At the lower values the gap-acceptance predictions can only be made to agree with the results of the empirical measurements by introducing a dependence of the “move-up” times on the value of the flows in the priority streams. The discrepancies at the higher values of priority flow are probably due to gap-forcing and priority reversal, both of which are commonly observed in the United Kingdom, but whose occurrence may vary from one country to another as a result of differences in driver behavior, legal sanctions, and enforcement policies. Several gap-acceptance models of roundabout capacities are compared and are found to be mutually inconsistent.
Supply and Demand Equilibration Algorithms for a Class of Market Equilibrium Problems
Authors: Dafermos Stella , Nagurney Anna
Published: October 2008

In this paper, we describe a family of progressive equilibration algorithms which can be used to solve a variety of market equilibrium problems such as the general spatial price equilibrium problem, the single price spatial price equilibrium problem, etc. They are relaxation-type algorithms which attempt to equilibrate the whole system by equilibrating successively each supply market (producer), or each demand market (consumer). One noteworthy feature of these algorithms is that, due to the special structure of the problem, the restricted equilibrium for each supply market (or demand market) can be obtained explicitly in closed form; another feature is that they are intuitive and straightforward to implement. Moreover, the computational results demonstrate that the algorithms are efficient and suitable for large-scale problems.
Savings by Split Delivery Routing
Authors: Dror Moshe , Trudeau Pierre
Published: October 2008

This paper examines a relaxed version of the generic vehicle routing problem. In this version, a delivery to a demand point can be split between any number of vehicles. In spite of this relaxation the problem remains computationally hard. The main contribution of this paper is in demonstrating the potential for cost savings through split deliveries. The solution scheme allowing for split deliveries is compared with a solution in which no split deliveries are allowed on a large set of 540 problems. Significant cost savings are realized both in terms of the total distance and the number of vehicles required. The vehicle routes constructed by our procedure, tend to cover cohesive geographical zones and retain some properties of optimal solutions.
Bibliographic Section
Authors: Meyer Michael D. , de Palma André , Hendrickson Chris
Published: October 2008

Public Infrastructure Planning and Management, by Jay M. Stein, editor, Sage Publications, 1988—reviewed by Michael D. Meyer.

Economic Evolution and Structural Adjustment, by D. Batten, J. Casti and B. Johansson, editors, Lecture Notes in Economics and Mathematical Systems, Springer Verlag, Berlin, 1985, 380 pp—reviewed by André de Palma.

Expert Systems in Construction and Structural Engineering, H. Adeli, editor, Chapman & Hall, London, 1988, 321 pp—reviewed by Chris Hendrickson.
An Integrated Inventory Allocation and Vehicle Routing Problem
Authors: Chien T. William , Balakrishnan Anantaram , Wong Richard T.
Published: October 2008

We address the problem of distributing a limited amount of inventory among customers using a fleet of vehicles so as to maximize profit. Both the inventory allocation and the vehicle routing problems are important logistical decisions. In many practical situations, these two decisions are closely interrelated, and therefore, require a systematic approach to take into account both activities jointly. We formulate the integrated problem as a mixed integer program and develop a Lagrangian-based procedure to generate both good upper bounds and heuristic solutions. Computational results show that the procedure is able to generate solutions with small gaps between the upper and lower bounds for a wide range of cost structures.
Application of Prediction-Error Minimization and Maximum Likelihood to Estimate Intersection O-D Matrices from Traffic Counts
Authors: Nihan Nancy L. , Davis Gary A.
Published: October 2008

The use of prediction error and maximum likelihood techniques to estimate intersection turning and through movement probabilities from entering and exiting counts is considered here. A maximum likelihood estimator for situations when full information on turning movement counts is available is derived and used as a component for a maximum likelihood algorithm which only requires entering and exiting counts. Several algorithms based on minimizing the error between observed and predicted exiting counts are also developed. Some actual traffic data are collected and used to develop realistic simulations for evaluating the various estimators. Generally, the maximum likelihood algorithm produced biased but more efficient estimates, while prediction error minimization approaches produced unbiased but less efficient estimates. Constraining the recursive version of the ordinary least-squares estimator to satisfy natural constraints did not affect its long run convergence properties.
A Lagrangian Relaxation Approach to Assigning Aircraft to Routes in Hub and Spoke Networks
Authors: Daskin Mark S. , Panayotopoulos Nicholaos D.
Published: October 2008

The problem of assigning aircraft to routes to maximize profits in a hub and spoke network is formulated as an integer linear programming problem. A Lagrangian relaxation of the problem is outlined together with heuristics for converting the Lagrangian solutions into primal feasible solutions and for improving on the solutions. Computational results from 324 runs spanning a range of problem sizes are reported. The results suggest that the Lagrangian relaxation is effective at providing an upper bound on the profits and the heuristics yield good solutions when the maximum number of aircraft required to fly all routes in the schedule is less than or equal to the number of available aircraft.
On the Bias Caused by Spatial Aggregation of Flows on the Estimation of the Degree of Scale Economies
Authors: Jara-Díaz Sergio R. , Donoso Pedro P.
Published: October 2008

From an economic viewpoint, transportation supply has been historically characterized through very aggregated descriptions of the output of a transportation firm. The use of measures like ton-miles or passenger-kilometers was standard practice through the end of the 1970's. Currently, the accepted description of transportation output is in terms of a vector of flows; aggregate measures have empirically been shown to be the source of significant problems in the economic analysis of transportation systems. In particular, the scarce empirical work on multioutput cost functions shows that the scalar volume-distance measure generates biased estimates of both marginal costs and degree of scale economies. In this paper, these biases are analyzed from an econometric viewpoint, using linear cost functions as first order approximations. Biases are expressed as differences of weighted sums, which are then used to show that, under reasonable statistical assumptions, the aggregated model causes a systematic overestimation of the degree of scale economies. This phenomenon is generalized to include a fairly general dependence of marginal costs on flows and distances.
The Asymmetric Distance Location Problem
Authors: Drezner Zvi , Wesolowsky George O.
Published: October 2008

In many situations the distance between two points is not a symmetric function; i.e., the distance from A to B is different from the distance from B to A. This is typical, for example, in rush hour traffic. We consider four models: the minisum or minimax problems with rectilinear or Euclidean distances. Efficient algorithms for the solution of these four problems are presented.
Maximin Center of Pendant Vertices in a Tree Network
Authors: Moon I. Douglas
Published: October 2008

The problem is to find a point in a tree whose distance to the closest pendant vertex is maximum. This paper presents a polynomial-time algorithm which reduces the given tree successively until such a point is found.
Maximal Direct Covering Tree Problems
Authors: Hutson Vicki Aaronson , ReVelle Charles S.
Published: October 2008

Concepts of coverage are extended to a problem of network design. Maximal covering tree problems are introduced to widen the applicability of the minimal spanning tree (MST), a classic network design problem, which defines the minimal length connection of all nodes in a network. Maximal covering tree problems relax the restriction that all nodes must be connected. Instead, maximal covering tree problems identify the best choices for subtrees in the spanning tree network based on the relative benefits and costs of connecting nodes. Two-objective integer programming (IP) models are formulated and solved for the maximal direct covering tree (1) on spanning networks in which arcs currently exist and (2) for the general spanning tree graph.
A Model for the Strategic Planning of National Freight Transportation by Rail
Authors: Crainic Teodor Gabriel , Florian Michael , Léal José-Eugenio
Published: October 2008

Recently, we developed a multimode multiproduct network optimization model, that is the network assignment method implemented in an interactive-graphic system for the strategic analysis and planning of national freight transportation systems, called STAN. For STAN, we developed a modeling framework of the rail freight transportation system, its components, operations and goals, that is adapted for both the strategic objectives of the planning system and the representation of the other transportation modes that compose a national multimode transportation system. The objective of this paper is to present and analyze the rail component of this strategic model of a national freight transportation system. We show how the rail model is integrated into STAN, as well as how this modeling framework may be used to represent a number of realistic scenarios.
A Successive Linear Approximation Procedure for Stochastic, Dynamic Vehicle Allocation Problems
Authors: Frantzeskakis Linos F. , Powell Warren B.
Published: October 2008

The Stochastic Dynamic Vehicle Allocation problem involves managing a fleet of vehicles over time in an uncertain demand environment to maximize expected total profits. The problem is formulated as a Stochastic Programming problem. A new heuristic algorithm is developed and is contrasted to various deterministic approximations. The paper presents computational results that were obtained by employing a Rolling Horizon Procedure to simulate the operation of the truckload carrier. Results indicate the superiority of the new algorithm over other approaches tested.
A Full Analytical Implementation of the PARTAN/Frank–Wolfe Algorithm for Equilibrium Assignment
Authors: Arezki Y. , Van Vliet D.
Published: October 2008

We show that an essential step in the PARTAN variant of the Frank–Wolfe algorithm for equilibrium assignment, the calculation of a minimal step length for maintaining feasibility, can be accomplished using either analytical formulas or simple rules.
Heuristics for Scheduling Aircraft and Crew during Airlift Operations
Authors: Sklar Michael G. , Armstrong R. D. , Samn S.
Published: October 2008

The Air Force is frequently placed in a situation where a large quantity of goods must be transported between various locations in a specified time period by Air Force personnel. The goods are of different and interrelated types; thus, the sequence of missions is specified to maintain a proper balance of goods at each location. Other vital considerations include both aircraft maintenance and health and alertness maintenance for pilots and personnel. Nevertheless, economy in operations needs to be demonstrated. Thus, the problem addressed in this paper is one of minimizing the number of crews used in the airlift, subject to crew rest requirements and the completion of all missions within the specified time frame. It is assumed that all routes, missions, and aircraft are predefined with limited crew availability. Results of computational testing are provided where the proposed algorithms are compared to the current Air Force methods.
Bibliographic Section
Authors: Labbé Martine , McNeil Sue , Meyer Michael D. , Ceder Avishai
Published: October 2008

Facilities Location: Models and Methods, R. F. Love, J. G. Morris and G. O. Wesolowsky, North Holland, Amsterdam, 1988—reviewed by Martine Labbé.

The Highway Design and Maintenance Standards Series:—five volumes—Vehicle Operating Costs: Evidence from Developing Countries, Andrew Chesher and Robert Harrison; Vehicle Speeds and Operating Costs: Models for Road Planning and Management, Thawat Watanatada, Ashok M. Dhareshwar and Paulo Roberto S. Rezende Lima; Road Deterioration and Maintenance Effects: Models for Planning and Management, William D. O. Paterson; and The Highway Design and Maintenance Standards Model, Volume 1. Description of the HDM-III Model, Volume 2. User's Manual for the HDM-III Model, Thawat Watanatada, Clell G. Harral, William D. O. Paterson, Ashok M. Dhareshwar, Anil Bhandari and Koji Tsunokawa; published for The World Bank by The Johns Hopkins University Press, Baltimore, 1987—reviewed by Sue McNeil.

New Transportation Fuels, A Strategic Approach to Technological Change, by Daniel Sperling, University of California Press, Berkeley, 1988—reviewed by Michael D. Meyer.

Introduction to the Theory of Traffic Flow, by Wilhelm Leutzbach, Springer-Verlag, Berlin, 1988, 204 pp.—reviewed by Avishai Ceder.
Equity Maximizing Facility Location Schemes
Authors: Berman Oded , Kaplan Edward H.
Published: October 2008

A plethora of methods exists for finding cost minimizing facility locations. However, it is generally true that once optimal locations have been found, the benefits derived from the facilities will not be distributed equally across customers due to differences in travel costs. Though some schemes aimed at providing more equitable facility locations have been proposed, none of these schemes are fully satisfactory in that there are always customers who are winners or losers with respect to the cost of travel. In this paper, we address the equity question using taxes (in the case of a central authority) or side payments (in the case of cooperating authorities) to redress benefit inequities. We show that the usual distance minimizing facility location formulations are still optimal, providing a very simple tax or side payment scheme is used to equalize benefits for all customers in the system. In the event that taxes or side payments cannot be utilized, our analysis leads to a natural method for locating facilities to minimize inequities. For the case of a single facility, the complexity of our approach is O(n4), where n is the number of customer demand points (nodes) in the service network.
Bibliographic Section
Authors: Johnson Rubin , Feo Thomas A. , Lamar Bruce W. , Belobaba Peter B. , Hensher David A. , Wolfe Robert A. , Hanson Susan , Solomon Ilan
Published: October 2008

Integer and Combinatorial Optimization, by George L. Nemhauser and Laurence A. Wolsey, John Wiley & Sons, New York, 1988, 763 pp.—reviewed by Rubin Johnson and Thomas A. Feo.

Discrete Optimization, by R. Gary Parker and Ronald L. Rardin, Academic Press, Boston, MA, 1988—reviewed by Bruce W. Lamar.

Airline Operations Research, by Dušan Teodorović, Volume 10 in Transportation Studies Series, Gordon & Breach, New York, 1989, 464 pp.—reviewed by Peter B. Belobaba.

Road Work: A New Highway Pricing and Investment Policy, by K. A. Small, C. Winston and C. A. Evans, The Brookings Institution, Washington, DC 1989, 128 pp.—reviewed by David A. Hensher.

Integrated Land Use and Transportation, by Tomas de la Barra, Cambridge University Press, 1989, 179 pp.—reviewed by Robert A. Wolfe.

Analytical Behavioural Geography, by Reginald G. Golledge and Robert J. Stimson. Croom Helm, New York, 1987, 337 pp. + Index—reviewed by Susan Hanson.

The New Era of Home-Based Work: Directions and Policies, edited by K. E. Christensen, Westview Press, Boulder, CO, 1988, 218 pp.—reviewed by Ilan Solomon.
Optimal Airline Seat Allocation with Fare Classes Nested by Origins and Destinations
Authors: Curry Renwick E.
Published: October 2008

Previous research in the optimal allocation of airline seats has followed one of two themes: marginal seat revenue or mathematical programming. Both approaches capture important elements of the revenue management problem. The marginal seat revenue approach accounts for the “nesting” of fare classes in computer reservation systems, but can only control seat inventory by bookings on legs. The mathematical programming approach will handle realistically large problems and will account for multiple origin–destination itineraries and side constraints, but it does not account for fare class nesting in the reservation systems. This paper combines both approaches by developing equations to find the optimal allocation of seats when fare classes are nested on an origin–destination itinerary and the inventory is not shared among origin–destinations. These results are applicable to seat allocation in certain reservations systems, point-of-sale control, and acceptance of groups over their entire itinerary. A special case of the analysis produces the optimal booking limits for leg-based seat allocation with nested fare classes.
Equilibrium Queueing Patterns at a Two-Tandem Bottleneck during the Morning Peak
Authors: Kuwahara Masao
Published: October 2008

Several researchers have analyzed queueing patterns at bottleneck sites on freeways during the morning peak. However, all previous studies have assumed that each commuter passes only one bottleneck during his commuting trip. Here, we consider the possibility that some commuters pass two bottlenecks on their way to work. The objective is to obtain cumulative arrival curves at each of the two bottlenecks, given who passes both bottlenecks and who passes only one, and their desired arrival times at their work places (work starting times). Each commuter using the freeway is assumed to have the same travel cost function which consists of time-dependent costs due to queueing delay (waiting time in a queue) and schedule delay (the time difference between his actual and desired arrival time at the work place). Commuter trips are assigned temporally so as to establish an equilibrium in which each commuter seeks to minimize his travel cost. The queue evolutions illustrate a service priority at the downstream bottleneck in favor of commuters passing only the downstream bottleneck. One of the countermeasures for this equity problem in the service priority would be to meter the favored commuters.
Two Moments Estimation of the Delay on Single-Track Rail Lines with Scheduled Traffic
Authors: Chen Bintong , Harker Patrick T.
Published: October 2008

A substantial literature exists on the estimation of the delay function for a single-track railroad with the assumption that the trains are uniformly distributed over time. In order to make the estimation more accurate and realistic, this paper provides the definition of delay functions for a scheduled railroad in which each train has a scheduled departure and arrival time. The key feature of this paper is that the uncertainty in the actual train departure time is explicitly taken into consideration. Since the variance of delay is important in the measurement of the reliability of a given set of schedules, both the mean and the variance of delay are estimated by solving a system of nonlinear equations.
Bibliographic Section
Authors: Hall Randolph W. , Meyer Michael D. , Heydecker Benjamin G.
Published: October 2008

Facility Location and the Theory of Production, by Arthur P. Hurter and Joseph S. Martinich, Kluwer Academic Publishers, Hingham, 1989, 272 pp.—reviewed by Randolph W. Hall.

Principles of Highway Engineering and Traffic Analysis, by Fred L. Mannering and Walter P. Kilareski, John Wiley & Sons, New York, 1990, 251 + xii pp.—reviewed by Michael D. Meyer.

Intersections Without Traffic Signals: Proceedings of an International Workshop, edited by W. Brilon, Springer-Verlag, Berlin, 1988, 328 pages, 88 figures—reviewed by Benjamin G. Heydecker.
A Model for Fleet Sizing and Vehicle Allocation
Authors: Beaujon George J. , Turnquist Mark A.
Published: October 2008

There are important interactions between decisions on sizing a vehicle fleet and decisions on utilizing that fleet. A model is formulated to optimize both sets of decisions simultaneously under dynamic and uncertain conditions. A network approximation to this model is presented and a solution procedure proposed. The convergence behavior of the solution procedure and the potential consequences of using simpler models to solve the fleet sizing and vehicle allocation problem are illustrated using several hypothetical problems. We conclude that this model is useful in identifying good strategies for the sizing of vehicle fleets and for the allocation of empty vehicles.
Tactical Scheduling of Rail Operations: The SCAN I System
Authors: Jovanović Dejan , Harker Patrick T.
Published: October 2008

This paper presents an overview of a decision-support model for the tactical scheduling of freight railroad traffic which is designed to support the weekly or monthly scheduling of rail operations. This initial version of the Schedule Analysis (SCAN) system is based upon notions from both simulation and combinatorial optimization, and is designed to provide decision makers with a tool for scheduling which provides a truly interactive system. After describing the conceptual underpinnings of the SCAN system and its associated algorithms, examples taken from a major railroad are used to illustrate the capabilities and limitations of the current system. Future research directions aimed at removing SCAN I's limitations are then discussed in light of recent advances in railroad management philosophies and technological advancements in this industry.
An Expeditious Risk Assessment of the Highway Transportation of Flammable Liquids in Bulk
Authors: Glickman Theodore S.
Published: October 2008

Risk assessment can be expedited and the results made more reliable by using existing information to its fullest advantage, especially when comparing relative risks. This principle is demonstrated in the context of transporting flammable liquid chemicals in bulk through New York City, where two alternative tank truck configurations are considered, depending on whether local fire department regulations or federal hazardous materials transportation regulations are followed. Spreadsheet calculations are used to estimate the risks on two different routes under average and worst-case assumptions. The results are subjected to an uncertainty analysis to help decide between the two alternatives, given the inherent randomness in the associated risks.