Eiichi Taniguchi

CITY LOGISTICS. NETWORK MODELLING AND INTELLIGENT TRANSPORT SYSTEMS

This book presents fundamental concepts and general approaches to City Logistics. City Logistics is the process of totally optimising urban logistics activities by considering the social, environmental, economic, financial and energy impacts of urban freight movement. City Logistics initiatives are required to solve urban freight transport problems including high levels of traffic congestion, negative environmental impacts, high energy consumption and a shortage of labour. The focus of this work is on modelling City Logistics. Modelling is of crucial importance, since estimates of the impacts generated by City Logistics measures are required for evaluating them. It highlights the formulation of mathematical models of vehicle routing and scheduling with Intelligent Transport Systems (ITS), optimal terminal locations and impact estimation by City Logistics measures. Heuristics techniques such as genetic algorithms, simulated annealing and tabu search are also given to identify approximate optimal solution of these combinatorial optimisation problems. ITS provides powerful tools for efficiently managing and operating vehicle fleets. Sophisticated logistics systems can now be developed by integrating Global Positioning Systems (GPS) and Geographical Information Systems (GIS) in conjunction with application software. In this context, the book presents a theoretical and practical treatment of modelling City Logistics based on ITS.

Optimal size and location planning of public logistics terminals

The concept of public logistics terminals (multi-company distribution centers) has been proposed in Japan to help alleviate traffic congestion, environment, energy and labor costs. These facilities allow more efficient logistics systems to be established and they facilitate the implementation of advanced information systems and cooperative freight systems. This paper describes a mathematical model developed for determining the optimal size and location of public logistics terminals. Queuing theory and nonlinear programming techniques are used to determine the best solution. The model explicitly takes into account traffic conditions in the network and was successfully applied to an actual road network in the Kyoto-Osaka area in Japan.

An evaluation methodology for city logistics

This paper presents a methodology for evaluating city logistics initiatives using a dynamic traffic simulation with optimal routing and scheduling. This methodology was applied to a test road network. The performance of three city logistics initiatives, advanced routing and scheduling systems, cooperative freight transport systems and load factor controls were assessed in terms of total costs and CO2 emissions by pickup/delivery trucks operations within the network. Results indicated that these initiatives were not only effective for reducing total costs, but also for CO2 emissions. The methodology presented here allows city planners to quantitatively evaluate city logistics initiatives.

MODELING CITY LOGISTICS

Urban freight systems are experiencing many problems due to higher levels of service and lower costs being demanded by shippers, with carriers having to operate in increasingly congested road conditions. Trucks operating in urban areas produce many negative impacts for society in terms of emissions, crashes, noise, and vibration. City logistics aims to globally optimize urban freight systems by considering the costs and benefits of schemes to the public as well as the private sector. The concepts of city logistics are introduced, and an outline is presented of some models that have recently been developed to predict the consequences of intelligent transportation systems. In particular, a stochastic vehicle routing and scheduling procedure that incorporates the variation of travel times is described. Results indicate that this approach can lead to significant reduction in operating costs by carriers as well as shorter routes with fewer trucks and increased reliability for customers. This procedure also reduces emissions and fuel consumption.

Designing Multimodal Freight Transport Networks: A Heuristic Approach and Applications

Designing multimodal freight transport networks can facilitate the economic development of regions and countries as well as help to reduce negative environmental impacts. It is therefore crucial that such be undertaken in areas where more priority is given on road-based freight transport systems. This paper proposes a model for strategic transport planning, particularly in freight terminal development and interregional freight transport network design. The model determines a suitable set of actions from a number of possible actions, such as improving the existing infrastructure or establishing new roads, railways, sea links, and freight terminals. Modelling is undertaken within the framework of bilevel programming, where a multimodal multiclass user traffic assignment technique is incorporated within the lower-level problem, whilst the upper-level problem determines the best combination of actions such that the freight-related benefit-cost ratio is maximised. The upper-level problem involves combinatorial optimisation, and a heuristic approach based on genetic local search is applied as a solution technique. Empirical results of the model as applied to an actual large-sized interregional intermodal freight transport network show that genetic local search could provide better performance as compared to other genetic algorithm-based, as well as tabu search-based, heuristics. The model is successfully applied to transport network planning in the Philippines, where the development of a freight transport network is necessary to increase the utilisation of other modes rather than road-based vehicles.

Predicting the effects of city logistics schemes

City logistics aims globally to optimize logistics systems within an urban area by considering the costs and benefits of schemes to the public and private sectors alike. Private shippers and freight operators aim to reduce their freight costs, while the community attempts to alleviate traffic congestion and environmental problems. City logistics initiatives attempt to minimize the total costs of freight movement within urban areas. Schemes for reducing the environmental and social costs as well as the economic costs are sought. This paper describes the development and application of mathematical computer-based models that have been used in the planning and evaluation of city logistics schemes. A detailed description of several modelling approaches that have been developed to predict the effects of specific city logistics schemes is presented. Integrated modelling approaches that combine both optimization and simulation, such as dynamic flow simulation and multi-agent systems, allow the effects of city logistics schemes to be predicted.

Visions for City Logistics

This paper presents visions for city logistics that are required to set targets of the activities that can be achieved using city logistics schemes. Our vision for city logistics consider three pillars that are guiding principles: (1) mobility; (2) sustainability; and (3) liveability. These three pillars are supported by goals that brace the structure of the visions and are comprised of: (a) global competitiveness; (b) efficiency; (c) environmental friendliness; (d) congestion alleviation; (e) security; (f) safety; (g) energy conservation; and (h) labor force. This paper discusses various features associated with urban freight transport issues to create mobile, sustainable and liveable cities. The paper concludes that there are a number of promising schemes that have the potential to fully realize the visions of city logistics, including: (1) establishing effective partnerships between key stakeholder groups; (2) implementing information and communication technology and intelligent transport systems; (3) promoting corporate responsibility; and (4) incorporating urban freight transport as an integral component of urban planning.

Evaluation of Distance-Based and Cordon-Based Urban Freight Road Pricing in E-Commerce Environment with Multiagent Model

E-commerce is gradually changing the way shoppers acquire goods and services. Shoppers seek ways to purchase goods easily through the Internet, and shippers or producers offer cheap ways to deliver goods to their customers through the services of carriers for home delivery. A theoretical model was established to evaluate city logistics schemes for multiple stakeholders before implementation. Policy measures to manage truck operations in the city and keep pollution levels at a minimum were evaluated. Cordon-based freight road pricing was found to provide better pollution reduction compared with distance-based pricing, but cordon-based pricing had less impact on areas outside a city. The problem was solved with a modeling approach for multiagent systems that used a vehicle routing problem with time windows, freight electronic marketplaces, and Q-learning.

Multi-agent systems modelling approach to evaluate urban motorways for city logistics

Government road authorities are constantly faced with the challenges of urbanization and traffic congestion requiring them to make good decisions for infrastructure developments. Several developed and developing countries have focused their concerns on building motorways for private and public transports for intercity connectivity and economic growth in the past. However, very few evaluation models were concerned about urban motorways for the benefit of urban freight transport. There may not even be an evaluation model for urban motorways development, which has considered the routing behaviour of truck movements in urban areas, especially if the main purpose for the urban motorway is for improving city logistics. Faced with the problems and concerns of the road authorities in Japan regarding capacity increase measures or other freight management schemes, this paper is an initial step to explore and provide the methodology to support the road authorities in their decision for urban motorway alternatives.

Effects Of Designated Time On Pickup/deliveryTruck Routing And Scheduling

This paper presents a mathematical model developed for investigating the effects of designated time windows on urban pickup/delivery truck routing and scheduling. Three heuristic techniques, genetic algorithms (GA), simulated annealing (SA) and tabu search (TS) were applied to obtain approximate optimal solutions for the urban pickup/delivery truck routing and scheduling problem with time windows. The performance of each of these techniques was compared using a small road network. The model was applied to investigate the effects of increasing the width of time windows.