Insights on disruptions as opportunities for transport policy change

Policy change is characterised as being slow and incremental over long time periods. In discussing a radical shift to a low carbon economy, many researchers identify a need for a more significant and rapid change to transport policy and travel patterns. However, it is not clear what is meant by rapid policy change and what conditions might be needed to support its delivery.Our contention in this paper is that notions of habit and stability dominate thinking about transport trends and the policy responses to them. We limit variability in our data collection and seek to design policies and transport systems that broadly support the continuation of existing practices. This framing of the policy context limits the scale of change deemed plausible and the scope of activities and actions that could be used to effect it.This paper identifies evidence from two sources to support the contention that more radical policy change is possible. First, there is a substantial and on-going churn in household travel behaviour which, harnessed properly over the medium term, could provide the raw material for steering behaviour change. Secondly, there is a growing evidence base analysing significant events at local, regional and national level which highlight how travellers can adapt to major change to network conditions, service availability and social norms. Taken together, we contend that the population is far more adaptable to major change than the policy process currently assumes.Disruptions and the responses to them provide a window on the range of adaptations that are possible (and, given that we can actually observe people carrying them out, could be more widely acceptable) given the current configuration of the transport system. In other words, if we conceptualise the system as one in which disruptions are commonplace, then different policy choices become tractable. Policy change itself can also be seen as a positive disruption, which could open up a raft of new opportunities to align policy implementation with the capacity for change. However, when set against the current framing of stability and habit, disruption can also be a major political embarrassment. We conclude that rather than being inherently problematic, disruption are in fact an opportunity through which to construct a different approach to transport policy that might enable rather than frustrate significant, low carbon change.     

Factors influencing bike share membership: An analysis of Melbourne and Brisbane

The number of bike share programs has increased rapidly in recent years and there are currently over 700 programs in operation globally. Australia’s two bike share programs have been in operation since 2010 and have significantly lower usage rates compared to Europe, North America and China. This study sets out to understand and quantify the factors influencing bike share membership in Australia’s two bike share programs located in Melbourne and Brisbane. An online survey was administered to members of both programs as well as a group with no known association with bike share. A logistic regression model revealed several significant predictors of membership including reactions to mandatory helmet legislation, riding activity over the previous month, and the degree to which convenience motivated private bike riding. In addition, respondents aged 18–34 and having docking station within 250 m of their workplace were found to be statistically significant predictors of bike share membership. Finally, those with relatively high incomes increased the odds of membership. These results provide insight as to the relative influence of various factors impacting on bike share membership in Australia. The findings may assist bike share operators to maximize membership potential and help achieve the primary goal of bike share – to increase the sustainability of the transport system.     

Achieving transport modal split targets at intermodal freight hubs using a model predictive approach

The increase of international freight commerce is creating pressure on the existing transport network. Cooperation between the different transport parties (e.g., terminal managers, forwarders and transport providers) is required to increase the network throughput using the same infrastructure. The intermodal hubs are locations where cargo is stored and can switch transport modality while approaching the final destination. Decisions regarding cargo assignment are based on cargo properties. Cargo properties can be fixed (e.g., destination, volume, weight) or time varying (remaining time until due time or goods expiration date). The intermodal hub manager, with access to certain cargo information, can promote cooperation with and among different transport providers that pick up and deliver cargo at the hub. In this paper, cargo evolution at intermodal hubs is modeled based on a mass balance, taking into account hub cargo inflows and outflows, plus an update of the remaining time until cargo due time. Using this model, written in a state-space representation, we propose a model predictive approach to address the Modal Split Aware – Cargo Assignment Problem (MSA–CAP). The MSA–CAP concerns the cargo assignment to the available transport capacity such that the final destination can be reached on time while taking into consideration the transport modality used. The model predictive approach can anticipate cargo peaks at the hub and assigns cargo in advance, following a push of cargo towards the final destination approach. Through the addition of a modal split constraint it is possible to guide the daily cargo assignment to achieve a transport modal split target over a defined period of time. Numerical experiments illustrate the validity of these statements.     

A carbon footprint-based closed-loop supply chain model under uncertainty with risk analysis: A case study

The management of products’ end-of-life and the recovery of used products has gained significant importance in recent years. In this paper, we address the carbon footprint-based problem that arises in a closed-loop supply chain where returned products are collected from customers. These returned products can either be disposed of or be remanufactured to be resold as new ones. Given this environment, an optimization model for a closed-loop supply chain (CLSC) in which carbon emission is expressed in terms of environmental constraints, i.e., carbon emission constraints, is developed. These constraints aim to limit the carbon emission per unit of product supplied with different transportation modes. Here, we design a closed-loop network where capacity limits, single-item management and uncertainty on product demands and returns are considered. First, fuzzy mathematical programming is introduced for uncertain modeling. Then, the statistical approach to the possibility to synthesize fuzzy information is utilized. Therefore, using a defined possibilistic mean and variance, we transform the proposed fuzzy mathematical model into a crisp form to facilitate efficient computation and analysis. Finally, the risk caused by violating the estimated resource constraints is analyzed so that decision makers (DMs) can trade off between the expected cost savings and the expected risk. We utilize data from a company located in Iran.     

基于协同的集装箱多式联运协调问题的研究

集装箱多式联运系统是一个复杂的运输工程系统,其组织协调工作仍存在严重不足,多式联运系统应具有的整体效果不能充分发挥。因此,只有各运输方式之间和参与多式联运的企业之间相互协同合作,才能达到联运全程系统化,实现多式联运的综合效益。本文对集装箱多式联运发展中存在的协调问题及影响因素进行分析,应用协同管理理论进行研究,对多式联运组织系统协调发展具有一定的理论指导作用。     

Tradable emission permit system for urban motorists: The neo-classical standard model revisited

This article deals with the feasibility of a tradable emission permit system (TEPs) for urban motorists. The objective is to develop a new microeconomic theoretical model to reduce urban pollution. We suppose that the city's regulating authority sets up a tradable emission permit system based on the number of kilometres covered by private cars. By the use of a Constant Elasticity of Substitution (CES) function, we determine the equilibrium under an environmental constraint and analyse the effects of a TEPs on social welfare. The aim is to find the optimal quantity of permits leading to the desired environmental objective. The analytical and numerical results of the model show the instrument's feasibility and efficiency. An important variable in the model must be taken into account: the knowledge of environmental damage. This variable will clearly influence the tool's success.     

Assessment of policies and detection of unintended effects: Guiding principles for the consideration of methods and tools in policy-packaging

Single policies or entire policy packages are often assessed using different methods aiming at a quantification of effects as well as the detection of undesired outcomes. The knowledge of potential impacts is essential to take informed policy actions. Hence, there is a constant need for efficient assessment approaches to support policy decision-making. A broad range of such assessment methods is used in policymaking. Some of them are using quantitative data; others are characterized by qualitative information, observations or opinions. Practical experiences with transport policy prove that these methods all have their pros and cons, but none of them are able to detect the full range of effects. This leads to important questions this article deals with, such as what are the strengths and limitations of the different tools and methods for assessing impacts, and how should different approaches be integrated into the policymaking processes?We analyze the ability of assessment methods to detect different kinds of intended and unintended effects, and introduce the concepts of structurally open (mainly qualitative) and structurally closed (mainly quantitative) methods. It is argued that these concepts support making the pros and cons of the tools and methods more explicit and, thus, allow integrating the different tools and methods into the process of policy packaging. Based on a policy package example, we provide practical recommendations on how to integrate different assessment methods adequately and show that both quantitative and qualitative tools should be used in different phases of the process. The main recommendation is to alternate the application of assessment methods with structurally open methods used in the beginning and the end of the policymaking process and applying structurally closed methods in between.     

城市公交场站设施规划

公交场站设施是重要的城市基础设施.本文重点探讨城市公交场站设施规划建设方面的一些问题,包括公交场站发展的规模、场站规划设置标准、场站建设模式等,并提出了相关的意见和建议.     

Transport network criticality metrics: a comparative analysis and a guideline for selection

ABSTRACT

Transport network criticality analysis aims at ranking transport infrastructure elements based on their contribution to the performance of the overall infrastructure network. Despite the wide variety of transport network criticality metrics, little guidance is available on selecting metrics that are fit for the specific purpose of a study. To address this gap, this study reviews, evaluates and compares seventeen criticality metrics. First, we conceptually evaluate these metrics in terms of the functionality of the transport system that the metrics try to represent (either maintaining connectivity, reducing travel cost, or improving accessibility), the underlying ethical principles (either utilitarianism or egalitarianism), and the spatial aggregation considered by the metrics (either network-wide or localised). Next, we empirically compare the metrics by calculating them for eight transport networks. We define the empirical similarity between two metrics as the degree to which they yield similar rankings of infrastructure elements. Pairs of metrics that have high empirical similarity highlight the same set of transport infrastructure elements as critical. We find that empirical similarity is partly dependent on the network’s topology. We also observe that metrics that are conceptually similar do not necessarily have high empirical similarity. Based on the insights from the conceptual and empirical comparison, we propose a five-step guideline for transport authorities and analysts to identify the set of criticality metrics to use which best aligns with the nature of their policy questions.