Collaborative Transportation Planning Research Articles

Interactive Web Application for Traffic Simulation Data Management and Visualization

As traffic simulation software becomes more effective for realistically simulating and analyzing traffic dynamics and vehicle interactions on the mesoscopic and microscopic level, the management, dissemination, and collaborative visualization of traffic simulation results produced by individual transportation planners presents a significant challenge. Existing online content management systems have a very limited capability in allowing users to query specific traffic simulation scenarios and geospatially visualize simulation results through shareable and interactive web interfaces. This paper presents a web-based application for promoting the archiving, sharing, and visualization of large-scale traffic simulation outputs. The application is developed to enhance cyber-physical controls, communications, and public education for collaborative transportation planning. Unique features of the web application include: (a) allowing users to upload their new traffic simulation scenarios (parameters and outputs), as well as search existing scenarios using easily accessible interfaces; (b) optimizing simulation output files with heterogeneous data formats and projected coordinate systems for web-based storage and management using a scalable and searchable data/metadata standard; (c) standardizing user-uploaded simulation outputs using web interfaces and data processing libraries with parallel computing capacity; and (d) providing shareable web visual interfaces for visualizing the traffic flow and signal information stored in simulation outputs (e.g., regional traffic patterns and individual vehicle interactions) and visually comparing multiple simulation outputs both spatially and temporally. The paper presents the conceptual design and implementation of this application, and demonstrates the application’s performance for sharing, comparing, and visualizing simulation outputs from VISSIM and SUMO, two commonly used traffic simulation software programs.

Collaborative transportation planning distinguishing old and new shippers for small-medium enterprise

This paper conducted a research on the vehicle routing problem (VRP) for small–medium enterprise (SMEs) considering new and old shippers. The problem is motivated by a real-world scenario found between Changzhou’s small or medium enterprises (Shippers) and transportation companies (Carriers). Since the service time is different for new and old shippers in the real world, we obtained a set of rich VRP considering time windows and the working time of the vehicle, as well as distinguishing between old and new shippers. We also propose a hybrid algorithm that consists of ant colony optimization (ACO) and tabu search (TS). Carrier’s trade-off point of orders’ number is calculated by the hybrid algorithm. Meanwhile, scenarios of deterministic versus stochastic shippers’ demand and collaborative versus non-collaborative carriers are optimized by the algorithm. The results show that the collaborative transportation planning could improve the profits of carriers.

Rolling horizon planning for a dynamic collaborative routing problem with full-truckload pickup and delivery requests

In order to improve their operational efficiency, small and mid-sized freight forwarders can establish horizontal coalitions in order to exchange customer requests. Decentralized operational transportation planning processes enabling request exchange among forwarders in spite of information asymmetry and distributed decision-making competences is referred to as collaborative transportation planning (CTP). CTP can help forwarders take advantage of economies of scale and reduce their costs of fulfilling customer requests compared to the case of isolated planning without request exchange. In order to exploit the potential of cost-savings embedded in CTP, appropriate request exchange mechanisms have to be developed. In this paper, the dynamic CTP problem of a coalition of freight forwarders serving full-truckload transport requests is studied. Two rolling horizon planning approaches are proposed to solve the dynamic routing problems. It is analyzed how the planning results, in particular the cost reduction realized by CTP, are influenced by different planning settings. Computational experiments show that the planning results of CTP are considerably superior to those obtained by isolated planning, and the realized cost-savings in percentage remain relatively constant, independently of the test settings.

Proportional egalitarian core solution for profit allocation games with an application to collaborative transportation planning

For a profit allocation game, one key issue is to find a fair allocation of profit among its players. In this paper, a proportional egalitarian core solution is proposed, which defines in the core of a game an allocation that takes account of each player’s contribution to the grand coalition. This solution concept generalises the egalitarian core solution for cooperative games. To efficiently compute the new solution, a row generation method is developed. The applicability of this new solution concept and the row generation method is demonstrated by an application to a carrier collaboration problem with numerical experiment results.

Collaborative transportation planning of less-than-truckload freight

Collaborative transportation planning (CTP) within a coalition of small and medium-sized freight carriers can be used as a powerful instrument to improve the operational efficiency of the coalition members. In such coalitions, transportation requests from different carriers are exchanged in order to reduce the total fulfillment costs. In this paper, the CTP for a set of independent carriers exchanging less-than-truckload transportation requests is considered. The realistic restriction that all collaborating partners have only limited capacities in their fleets is included in the consideration. To keep their autonomy, coalition members keep their sensitive information including customer payments and cost structures unexposed during CTP. A new decentralized request exchange mechanism for CTP is proposed while only vehicle routes are considered for exchange. It is tested on some newly generated instances and the CTP solutions are compared with those obtained by isolated planning without collaboration and those obtained by a heuristic approach for the centralized planning problem. The results indicate that our mechanism is very efficient and effective in terms of realizing potential cost-savings by CTP, even when capacity limitations and restrictions on the exposure of information are explicitly considered.

Mathematical model and solution approach for carriers' collaborative transportation planning in less than truckload transportation

Collaborative transportation is achieved when multiple carriers or shippers form a partnership to optimise their transportation operations by sharing vehicle capacities and transportation tasks in order to cut empty back hauls and to increase vehicle utilisation rates. This paper studies a carriers’ collaborative transportation planning problem in less than truckload transportation (CTPLTL) with pickup and delivery tasks and proposes a two-step solution approach for solving the problem. Firstly, a mixed integer programming model for the problem is proposed and a Lagrangian relaxation approach is developed to solve this model. Secondly, a set of feasible vehicle tours corresponding to the transportation plan of the carriers in collaborative transportation is constructed from the solution of the model. The performance of our proposed model and solution approach is evaluated by randomly generated instances.

Assessing the experience of mandated collaborative inter-jurisdictional transport planning in the United States

This paper explores collaborative transport planning among governmental authorities where jurisdictions overlap and the lines of authority are ambiguous or unclear–an increasingly common situation in this era of waning trade and travel restrictions. We do this by examining the experience of mandated collaborative transportation planning among state departments of transportation (DOTs) and metropolitan planning organizations (MPOs) in the USA following a significant change to national surface transportation policy in the early 1990s. To understand how state transport planning and plans changed following the inter-jurisdictional collaboration mandated by passage of the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA), we examine recent statewide transport planning in 14 of the largest US states and conducted interviews with 66 state and regional planners. We find that, despite the myriad topics that state DOTs tried to include within their comprehensive statewide plans, these plans have had, at best, a limited influence on metropolitan transport planning and activities. Despite this, we find that the mandated collaborative planning did help to increase inter-agency coordination on issues (1) where network or environmental externalities transcend regional boundaries, (2) that require the political clout of a higher-level governmental authority to enforce locally unpopular decisions, or (3) that take advantage of institutional economies of scale.