Dynamic Transportation Planning Research Articles

A stochastic programming model for emergency supply planning considering transportation network mitigation and traffic congestion

How to conduct effective and efficient emergency supply planning is a challenging task. In this paper, we tackle a general emergency supply planning problem. The problem not only integrates the decisions of transportation network mitigation and emergency supply pre-positioning before disasters, but also considers post-disaster dynamic transportation planning with traffic congestion effects incorporated. We formulate this problem as a two-stage stochastic programming model, which aims to minimize the expected total cost related to various disaster mitigation, preparedness, and response decisions. A variant of the model is optimally solved by applying a generalized Benders decomposition algorithm, which significantly outperforms state-of-the-art global optimization solvers. Finally, a case study for a hurricane threat in the southeastern U.S. is conducted to demonstrate the advantages of our model and to illustrate insights on the optimal network mitigation and pre-positioning plan as well as the transportation plan. It is shown that considering traffic congestion effects and dynamic transportation plans brings about spatial and temporal flexibility for achieving better emergency supply plans.

Constructing urban dynamic transportation planning strategies for improving quality of life and urban sustainability under emerging growth management principles

Since the beginning of twenty-first century, urban development worldwide has successively deviated from our ideal design and original plans. There have subsequently accompanied numerous urban problems, such as congestion, serious air pollution, urban endlessly sprawl and inappropriate land development with low urban density. All of these features we often called urban illnesses significantly created negative influence to our urban life. The growth management concepts were thus emerged firstly to confront such negative influence. Not uniquely, numerous developed countries also failed to achieve its initial development strategy goals and soon afterwards implemented a more specific and essential strategies in which it introduced three innovative growth constructions: smart growth, sustainable growth, and inclusive growth. They confidently claimed that urban development would certainly improve quality of life (QoL) if the concept of development may be replaced by the concept of growth. Following various innovative growth constructions or management principles, contemporary urban agents including practical planners or official decision units, thus could pursue urban sustainable development and QoL simultaneously.Based on the current status and development processes, this study aimed at the urban transportation planning strategy and its dynamics according to the advanced international experiences. Firstly, this study surveyed international experiences or researches related to quality of life concepts, growth management principles as well as sustainable transport issues. Secondly, we then make an effort to identify critical sustainable transportation indicators under various growth constructions or management principles through the Fuzzy Delphi Method (FDM) modeling results. The FDM requires repetitive surveys to confirm the final convergent values of all expert opinions and exclude less feasible sustainable transportation indicators at the same time. Thirdly, the Dynamic Network Process (DNP) was also applied to the expert survey to obtain four different weights during the period from 2014 to 2040 in response to actual changes or future trends of each indicator we selected. And then this research combined Gray Forecasting Model (GFM) to reflect changes or trends of each indicator over time by above several DNP surveys for making more realistic and suitable priorities or weights to achieve the efficiency of resource allocation. Finally, this study tried to conduct an empirical analysis with New Taipei City in Taiwan to indicate our planning philosophy and consequently validate planning strategies emphasized by this study. We believes that research frameworks and findings here not only provide new insights into the functioning of current growth constructions or management principles, but also could be used as a well reference basis for practical planners or official decision units to facilitate QoL and urban sustainability in further.

Integration of aggregate distribution and dynamic transportation planning in a supply chain with capacity disruptions and the ripple effect consideration

We study the dynamic planning decisions of a logistics service provider that is in charge of the integrated supply chain (SC) planning. We examine an SC with multiple products, suppliers, transit nodes and customers in a multi-period mode. The logistics service provider is responsible for aggregate distribution planning and operative dynamic transportation planning. It is to decide on aggregate distribution flows as well as on the time-dependent intensities (i.e. transportation batches). These decisions are tightly incorporated but previous research considered them mostly isolated. This is quite natural since these problems contain data of different detail degree, which can be hardly incorporated in only one model. To resolve this problem, we present a hybrid multi-period, multi-commodity distribution–transportation model as an optimal control problem blended with mathematical programming. This contribution has some particular features. First, it extends previous research by elaborating on the dynamic optimal control model. Second, it considers multi-period problem statement with multiple products and alternative transportation channels. Third, we represent the integrated dynamic SC planning in order to take into account the ripple effect. With the results of this study, the dynamic issues in integrated logistics planning in the SC can be addressed, and an intelligent solution to an important problem of SC management has been proposed.

Dynamic Transportation Planning and Operations: Concept, Framework and Applications in China

Transportation systems are large, complex and dynamic. Traditional transportation planning methods are based on 4-step travel demand forecast models, which are not good at describing the dynamic characteristics of transportation systems. On the basis of the existing research, this paper presents the concept of Dynamic Transportation Planning and Operations (DTPO), and explains the connotation and application of DTPO in recurrent and non-recurrent scenarios. In addition, a simulation- based DTPO Approach (SDTPOA) is put forward and a DTPO Platform which integrates travel demand model and traffic simulator is designed. The functions of each module in the DTPO Platform are explained in details as well as the operating mechanism of the platform under both recurrent and non-recurrent situations. The DTPO Platform adopts agent-based travel demand model, which can depict the real world better so as to replace the conventional travel demand models. As the key component of the DTPO Platform, Agent-based Modeling (ABM) is analyzed in this paper.

STRUCTURE DYNAMICS CONTROL-BASED INTEGRATION OF AGGREGATE DISTRIBUTION AND DYNAMIC TRANSPORTATION PLANNING

We study dynamic planning decisions of a logistics service provider that in charge of the integrated supply chain (SC) planning. We examine an SC with multiple products, suppliers, transit nodes, and customers. The logistics service provider is responsible for aggregate distribution planning and operative dynamic transportation planning. It is to decide on aggregate distribution flows as well as on the time-dependent intensities (i.e., transportation order quantities). These decisions are tightly incorporated but previous research considered them mostly isolated. This is quite naturally since these problems contain data of different detail degree which can be hardly incorporated in only one model. To resolve this problem, we present a hybrid multi-period distribution–transportation model as an optimal control problem blended with linear programming. This contribution has some particular features. First, it extends previous research by elaborating on the dynamic optimal control model. Second, it considers multi-period problem statement with multiple products and alternative transportation channels. Third, we represent the integrated SC planning in terms of structure dynamics control theory in order to take into account execution stage and adaptation. With the results of this study, the dynamic issues in integrated logistics planning in the SC can be addressed, and an intelligent solution to the important problem of SC management has been proposed. Copyright © 2013 IFAC

Transport system responsiveness improvement

PurposeThe coping of demand oscillation is an important challenge in dynamic transport planning. A reliable request fulfillment must be provided even if the number of incoming requests temporarily climbs over the expected demand and resource scarceness appears. The aim of this paper is to propose an innovative planning approach that enables a transportation fleet to maintain a sufficiently high percentage of timely‐fulfilled customer requests even in demand peak situations.Design/methodology/approachThe effectiveness of the new approach is verified in computational simulation experiments. Quantifications for the system's responsiveness are proposed. Then, the quantified knowledge about the intermediate responsiveness is exploited to adjust the decision model representing the next schedule update task in a rolling horizon re‐planning.FindingsThe observed simulation results suggest the suitability of the proposed approach. An adjustment of the plan update model supports the maintenance of a high percentage of timely completed requests during and after the demand peak.Research limitations/implicationsThe generic approach presented and evaluated here motivates an adaptation to other more practical problem settings, in order to show its general applicability.Practical implicationsThe proposed methodology contributes to the current demand for computational support for increasing the responsiveness of logistic systems.Originality/valueThe original contribution of this paper is the autonomous feedback‐controlled adjustment of decision preferences which enables a rolling horizon re‐planning framework to maintain a stable output performance even if the input oscillates significantly over time.

Gravity models for dynamic transport planning: Development and implementation in urban networks

This paper describes the development and comparison through a real-life implementation of dynamic extensions of the entropy-based gravity model of trip distribution for dynamic transport planning purposes in urban networks. The single dynamic gravity model (SDGM) accounts only for the inter-period (long-term) evolution of travel demand. The doubly dynamic gravity model (DDGM) takes into account both the inter-period and intra-period (short-term or within-day) evolution of travel demand. The computational analysis and explanation of the differences between the two models are demonstrated in relation to different demand inputs, model parameters and performance measures.

Approaches to dynamic transport planning

Dynamic transport planning refers to the analysis of the problem of choice of implementation date of the construction or improvement of transport facilities. This analysis may also include consideration of stage construction or progressive improvements in quality and/or capacity over time, beginning from some relatively low standard. A transport facility is defined as a vehicle (e.g., automobile, airplane) or a supporting facility (e.g., highway, port). There appears at present to be a serious lack of any truly comprehensive evaluation of the essentials of the problem of choice of implementation date. It is the intent of the ensuing presentation to help to rectify that situation by introducing new concepts which structure the timing problem. The concepts are based on a suggested classification of future traffic and definitions of independent and indivisible facilities. In addition, volume of traffic and benefits of a transport facility are recognized to be dependent on calendar time and the facility's age. Presently, no uniform theoretical framework exists for establishing the optimal time for constructing new facilities or improving existing ones. A framework based on the aforementioned concepts is introduced. It distinguishes between the phasing of projects through time in the absence of budget constraints and this phasing in the presence of such restrictions. The specific procedures suggested in this paper for the analysis of the problem of choice of implementation date apply to any individual transport facility and tend to unify the concepts involved in dynamic transport planning. The article concludes with a survey of current approaches to dynamic transport planning and discusses these in the light of the above framework.