Showing papers in "Transportation Research Part E-logistics and Transportation Review in 2009"

Port Choice and Freight Forwarders

Abstract: In light of the growing supply chain power of 3PLs and very limited empirical studies on port choice from the freight forwarders’ perspective, this paper tries to evaluate the major factors influencing port choice from the Southeast Asian freight forwarders’ perspective, their decision-making style and port selection process and draw out some policy implications for port operators and authorities. Efficiency is found to be the most important factor followed by shipping frequency, adequate infrastructure and location. Their selection process is complex and a two-stage process and supports the new approach that models ports within the framework of a supply chain.

A decision support system for vehicle relocation operations in carsharing systems

Abstract: This paper presents a novel three-phase optimization-trend-simulation (OTS) decision support system for carsharing operators to determine a set of near-optimal manpower and operating parameters for the vehicle relocation problem. Tested on a set of commercially operational data from a carsharing company in Singapore, the simulation results suggest that the manpower and parameters recommended by the OTS system lead to a reduction in staff cost of 50%, a reduction in zero-vehicle-time ranging between 4.6% and 13.0%, a maintenance of the already low full-port-time and a reduction in number of relocations ranging between 37.1% and 41.1%.

Locating Road-Vehicle Refueling Stations

Abstract: This study follows the concept of set cover for proposing a refueling-station-location model using a mixed integer programming method, based on vehicle-routing logics. Its solution uses only the easy-obtain data of the origin-destination distance matrix. A case study that focuses on the siting of refueling stations for achieving multiple origin-destination intercity travel via electric vehicles on Taiwan demonstrates the applicability of the model. Sensitivity analysis shows that greater vehicle range will result in a lower number of refueling stations that need to be sited. Range is crucial in reducing the facility-location costs, and therefore is an important issue in the development of alternative-fuel-vehicle technology.

Dynamic network design for reverse logistics operations under uncertainty

Abstract: The design of reverse logistics network has attracted growing attention with the stringent pressures from environmental and social requirements In general, decisions about reverse logistics network configurations are made on a long-term basis and factors influencing such reverse logistics network design may also vary over time This paper proposes dynamic location and allocation models to cope with such issues A two-stage stochastic programming model is further developed by which a deterministic model for multiperiod reverse logistics network design can be extended to account for the uncertainties A solution approach integrating a recently proposed sampling method with a heuristic algorithm is also proposed in this research A numerical experiment is presented to demonstrate the significance of the developed stochastic model as well as the efficiency of the proposed solution method

Heuristics for the Integration of Crane Productivity in the Berth Allocation Problem

Abstract: In this paper, the combined problem of berth allocation and crane assignment in container terminals is investigated. The proposed problem formulation includes important real world aspects such as the decrease of marginal productivity of quay cranes assigned to a vessel and the increase in handling time if vessels are not berthed at their desired position at the quay. To solve the problem a construction heuristic, local refinement procedures, and two meta-heuristics are presented. These methods perform well on a set of real world like instances. The results emphasize the important role of quay crane productivity in berth planning.

Optimal rail-road container terminal locations on the European network

Abstract: The European transport policy has focused on sustainable transport solutions, among which intermodal transport is a key player. However, its efficiency is strongly dependent on the location of the container terminals. In this paper, a set of estimated potential locations is used as input for an iterative procedure based on the p-hub median problem that takes the variation in trans-shipment costs according to the number of trans-shipped containers into account. The final results are the optimal locations for European transfer terminals embedded in a hub-and-spoke network.

The impacts of Radio Frequency Identification (RFID) technology on supply chain costs

Abstract: Radio Frequency Identification (RFID) is regarded as a promising technology for the optimization of supply chain processes since it improves manufacturing and retail operations from forecasting demand to planning, managing inventory, and distribution. This study uses a simulation model to calculate the expected benefits of an integrated RFID system on a three-echelon supply chain obtained through performance increases in efficiency, accuracy, visibility, and security level. The study investigates how the product value, lead time, and demand uncertainty affect the performance of the integrated RFID supply chain in terms of cost factors at the echelon level.

Shopping mode choice: Physical store shopping versus e-shopping

Abstract: This study aims to explore how consumers evaluate these time attributes; i.e., the value of time, when they are facing a shopping mode choice between physical store shopping and e-shopping. For this purpose, it conducts an experiment to acquire data on respondents’ stated preference choices between physical bookstore shopping and online bookstore shopping. It is finally found that the value of delivery time for a purchased book from an online bookstore to a consumer is approximately $0.53 per day, which means an online bookstore will have to lower a book’s price by $0.53 to attract a physical bookstore shopper if the delivery is delayed for one day. It is also found that in terms of monetary values, avoiding a shopping trip produces far more benefits than bearing waiting for the delivery of books for an online purchase.

Environmental-Regulation Pricing Strategies for Green Supply Chain Management

Abstract: This paper demonstrates that a proper design of environmental-regulation pricing strategies is able to promote Extended Product Responsibility for green supply chain firms in a competitive market. A differential game model comprising Vidale–Wolfe equation has been established in light of sales competition and recycling dynamics as well as regulation related profit function. Analytic solutions of Markovian Nash equilibriums are provided with the necessary condition derived from Hamilton–Jacobi–Bellman equations. We found that governments should opt to gradually raise regulation standards so that rational manufacturers will gradually improve its product recyclability, and, in turn, Extended Product Responsibility will get promoted.

The optimization of the closed-loop supply chain network

Abstract: This paper develops a model of a general closed-loop supply chain network, which includes raw material suppliers, manufacturers, retailers, consumers and recovery centers. The objective of this paper is to formulate and optimize the equilibrium state of the network by using the theory of variational inequalities. Several examples and figures are used to describe the effects of parameters (the return ratio, the transformation rate of raw materials, and the transformation rate of recyclable products) on the equilibrium shipments and net revenues.

Container fleet sizing and empty repositioning in liner shipping systems

Abstract: This paper considers the joint container fleet sizing and empty container repositioning problem in multi-vessel, multi-port and multi-voyage shipping systems with dynamic, uncertain and imbalanced customer demands. The objective is to minimize the expected total costs including inventory-holding costs, lifting-on/lifting-off costs, transportation costs, repositioning costs, and lost-sale penalty costs. A simulation-based optimization tool is developed to optimize the container fleet size and the parameterized empty repositioning policy simultaneously. The optimization procedure is based on Genetic Algorithms and Evolutionary Strategy combined with an adjustment mechanism. Case studies are given to demonstrate the results.

Multi-port vs. Hub-and-Spoke port calls by containerships

Abstract: This paper addresses the design of container liner shipping networks taking into consideration container management issues including empty container repositioning. We examine two typical service networks with different ship sizes: multi-port calling by conventional ship size and hub-and-spoke by mega-ship. The entire solution process is performed in two phases: the service network design and container distribution. A wide variety of numerical experiments are conducted for the Asia–Europe and Asia–North America trade lanes. In most scenarios the multi-port calling is superior in terms of total cost, while the hub-and-spoke is more advantageous in the European trade for a costly shipping company.

An effective genetic algorithm for the fleet size and mix vehicle routing problems

Abstract: This paper studies the fleet size and mix vehicle routing problem (FSMVRP), in which the fleet is heterogeneous and its composition to be determined. We design and implement a genetic algorithm (GA) based heuristic. On a set of twenty benchmark problems it reaches the best-known solution 14 times and finds one new best solution. It also provides a competitive performance in terms of average solution.

Containership routing with time deadlines and simultaneous deliveries and pick-ups

Abstract: In this paper we seek to determine optimal routes for a containership fleet performing pick-ups and deliveries between a hub and several spoke ports. A capacitated vehicle routing problem with pick-ups, deliveries and time deadlines is formulated and solved using a hybrid genetic algorithm for establishing routes for a dedicated containership fleet. Results on the performance of the algorithm and the feasibility of the approach show that a relatively small fleet of containerships could provide efficient services within deadlines. Moreover, through sensitivity analysis we discuss performance robustness and consistency of the developed algorithm under a variety of problem settings and parameters values.

An Exact Solution Approach for Vehicle Routing and Scheduling Problems with Soft Time Windows

Abstract: A new column generation based exact optimization approach for the vehicle routing and scheduling problem with semi soft time windows (VRPSSTW) is presented. Elementary shortest path problem with resource constraints and late arrival penalties is solved as a subproblem, which rises from the Dantzig–Wolfe decomposition method. Exact solutions of VRPSSTW and hard time windows variant are compared on Solomon’s benchmark instances as well as on an instance based on Tokyo road network. It was found that the VRPSSTW solution results in fewer routes thus overall costs are reduced and late arrival penalties contribute only a small fraction to total cost.

A weighted Logit Freight Mode Choice Model

Abstract: The paper describes the estimation of a weighted discrete choice model applicable for analysing choice of mode and crossing for freight in the Oresund region. The study finds that, by applying a weighted logit approach, it is possible to establish a suitable decoupling of agents and shipments. Moreover, by assessing preferences on the basis of a representative baseline OD matrix it is possible to better reflect the dependence between mode substitution effects and geography/infrastructure. The paper presents demand elasticities with respect to monetary cost and travel time as well as value-of-time estimates for five modes and thirteen commodity groups.

Principles of Micro-Behavior Commodity Transport Modeling

Abstract: This paper presents an agent-based approach to commodity transport modeling. It assesses the effects of behavior-oriented transport policy measures while taking complex logistics reaction patterns into account. It is structured by modules describing company generation, supplier choice, shipment-size choice, carrier choice and tour construction. The behavior of individual actors is simulated using normative logistics models and accumulated market knowledge. Using a bottom-up approach, shippers and carriers interact through simulated auctions of transport contracts resulting in the generation of tours. Simulations using the model prototype INTERLOG calibrated with German data demonstrate the capabilities and limitations of this approach.

Simplifying choice through attribute preservation or non-attendance: Implications for willingness to pay

Abstract: There is a growing interest in seeking out rules that individuals invoke when processing information in choice experiments. A rule that is attracting attention in stated choice studies is the extent to which respondents attend to or ignore one or more attributes in processing the information on offer. A model specification method is implemented in the context of a stated choice data set where car drivers choose between tolled and non-tolled routes. The evidence into a willingness to pay (WTP) for travel time savings is obtained, and contrasted with the results from the traditional full preservation model. The evidence suggests that the WTP is sufficiently different and higher, on average.

Effect of Block Width and Storage Yard Layout on Marine Container Terminal Performance

Abstract: Block widths ranging from two to fifteen rows in a marine container terminal are evaluated by a fully-integrated, discrete event simulation model Experiments consider dozens of yard configurations and four container terminal settings that are designed to reproduce the microscopic, stochastic, real-time environment at a multiple-berth facility Results show that the quay crane rate is concave with respect to block width when the yard storage capacity and amount of yard equipment is constant The optimal block width ranges from 6 to 12 rows depending on the amount of equipment deployed and the size, shape, and throughput of the terminal

Low-cost airlines and airport competition

Abstract: An important question from the viewpoint of competition analysis in the air transport industry is the extent to which low-cost airlines operating from a secondary airport compete with full-service airlines serving a main airport in a multiple airport region. In this paper we address the issue of the competition between full-service and low-cost airlines serving adjacent airports in the Greater London using econometric estimation of demand structure (own- and cross-price elasticities). Our analysis follows the methodology in (Pels, E., Nijkamp, P., Rietveld, P., 2000. Airport and airline competition for passengers departing from a large metropolitan area. Journal of Urban Economics, 48 (1), 29–45, Pels, E., Nijkamp, P., Rietveld, P., 2003. Access to and competition between airports: a case study for the San Francisco Bay area. Transportation Research Part A: Policy and Practice, 37 (1), 71–83). It is based on the nested logit model which we use to capture three key dimensions of passenger choice: air fare, surface-access costs and frequency. We obtained estimates of the own- and cross-price elasticities, which was the focus of our interest. On the basis of our understanding of the industry dynamics we find these estimates, especially of the cross-price elasticities, to be on the low side.

A reactive tabu search algorithm for the multi-depot container truck transportation problem

Abstract: A container truck transportation problem that involves multiple depots with time windows at both origins and destinations, including the reposition of empty containers, is formulated as a multi-traveling salesman problem with time windows (m-TSPTW) with multiple depots. Since the problem is NP-hard, a cluster method and a reactive tabu search (RTS) algorithm are developed to solve the problem. The two methods are compared with the mixed integer program which can be used to find optimum solutions for small size problems. The computational results show that the developed methods, particularly the RTS algorithm, can be efficiently used to solve the problem.

Modelling the Joint Access Mode and Railway Station Choice

Abstract: This study models the choices of Dutch railway users. We find a steeper negative distance effect on the utility of departure stations accessed by the non-motorized modes of walking and bicycle as compared to the motorized modes of car and public transport. Availability of parking places and bicycle standing areas have a positive effect on the choice of departure railway stations accessed by car and bicycle, respectively. Public transport frequency has a positive whereas travel time has a negative effect on the choice of departure stations accessed by public transport. The derived rail service quality index (RSQI), which provides a measure of rail accessibility to all other stations, has a significant and positive effect on the choice of departure stations accessed by all modes. The outcome of this paper can be used to develop a comprehensive railway accessibility indicator for neighbourhoods, for hedonic pricing studies.

Service quality gaps of business customers in the shipping industry

Abstract: This paper extends the gaps model of [Zeithaml, V.A., Parasuraman, A., Berry, L. 1990. Delivering Quality Service: Balancing Customer Perceptions and Expectation. The Free Press, New York] from the service provider to the business customer side by examining two service quality (SQ) gaps. One is the SQ gap between types of business customers and the other is the SQ gap among employee statuses of business customers. Besides that, the five-factor SERVQUAL measure as the initial hypothesized model is also tested. The applicability of SERVQUAL to measuring the perceived SQ of customers in the shipping industry of Taiwan is rejected empirically. The existence of the two hypothesized gaps is verified by the method of MANOVA.

Statistical estimation of railroad congestion delay

Abstract: This research identifies factors that are the major contributors to freight rail congestion using statistical analysis. Total train running time is predicted based on free running time predictors (horsepower per ton, track topography and slow orders) and congestion-related factors (meets, passes, overtakes, prior time periods’ train counts, total train hours, train spacing variability, and train departure headway). Primary congestion predictive factors (meets, passes, overtakes) are consistently found to have the largest effect on congestion delay. The predictive equations are used to forecast average monthly train running time with a 4.6% mean absolute percent error.

Dynamic Price Dispersion in Airline Markets

Abstract: This study analyzes the factors that explain the variations of daily airfares across fare histories, or dynamic price dispersion. Empirical analyses show that dynamic price dispersion is significantly influenced by demand characteristics variables such as population, income and the share of business passengers, as well as by competitive pressures stemming from the presence of low-cost carriers, but not by the competition intensity. The impact of these variables intensifies as the departure date approaches. These results imply that in the presence of low-cost carriers, full-service carriers tend to adopt a more aggressive high-low pricing strategy.

A heuristic algorithm for yard truck scheduling and storage allocation problems

Abstract: The yard truck scheduling and the storage allocation are two important decision problems affecting the efficiency of container terminal operations. This paper proposes a novel approach that integrates these two problems into a whole. The objective is to minimize the weighted sum of total delay of requests and the total travel time of yard trucks. Due to the intractability of the proposed problem, a hybrid insertion algorithm is designed for effective problem solutions. Computational experiments are conducted to examine the key factors of the problem and the performance of the proposed heuristic algorithm.

Operational efficiencies across Asia Pacific airports

Abstract: This paper analyses various dimensions of operational efficiencies in major Asia Pacific airports through Data Envelopment Analysis (DEA) models that simultaneously account for external macroeconomics and price factors. Results from this study show that technical, scale and mix efficiencies are high among the major Asia Pacific airports. In addition, significant disparities in cost efficiencies were detected amongst these airports. These disparities can be attributed to the presence of country-specific effect and differences in allocative efficiencies. A virtual airport is then introduced as a superior performer to rank the efficiency performances of airports.

Anticipatory algorithms for same-day courier dispatching

Abstract: This paper describes anticipatory algorithms for the dynamic vehicle dispatching problem with pickups and deliveries, a problem faced by local area courier companies. These algorithms evaluate alternative solutions through a short-term demand sampling and a fully sequential procedure for indifference zone selection. They also exploit an unified and integrated approach in order to address all the issues involved in real-time fleet management, namely assigning requests to vehicles, routing the vehicles, scheduling the routes and relocating idle vehicles. Computational results show that the anticipatory algorithms provide consistently better solutions than their reactive counterparts.

Optimizing Shipment, Ordering and Pricing Policies in a Two-Stage Supply Chain with Price-Sensitive Demand

Abstract: In this paper we focus on a two-stage supply chain consisting of one vendor and one buyer. We develop an integrated production–inventory–marketing model to determine the relevant profit-maximizing decision variable values. The model proposed is based on the joint total profit of both the vendor and the buyer, and it finds out the optimal ordering, shipment and pricing policies. We are able to ascertain the optimal decision variable values employing an analytical solution procedure. The numerical evidence suggests that it is more beneficial for the buyer and the vendor to cooperate with each other when the demand is more price sensitive.

Measuring the performance of multimode bus transit: A mixed structure network DEA model

Abstract: The aim of this paper is to propose a mixed structure network data envelopment analysis (MSNDEA) model which allows a representation of a parallel production serial connection of consumption processes in a unified framework and hence can be used to simultaneously estimate the production efficiency, service effectiveness and operational effectiveness of multimode transit firms. To do this, Taiwan’s bus transit system is selected for the empirical applications. The main advantages of the MSNDEA model are in contexts where internal linkage and shared inputs between activities can be considered in this model, and the model structure is more realistic than the conventional one.