A traffic accident morphology diagnostic model based on a rough set decision tree

ABSTRACT

To build a traffic safety feature model and to quantify accident influences caused by some traffic violation behaviors of drivers, an accident diagnostic decision-making model is established. For the purpose of diagnosing accident morphologies, rough set theory is applied and the influence of traffic factors of different accident morphologies is quantified through calculating the degree of attribute importance, selecting core traffic factors and adopting a C4.5 decision tree algorithm. In the paper, road traffic accident data from 2008 to 2013 in Anhui Province are used. Typical rules are selected, targeted strategy proposals are put forward, and then, a scientific and reasonable diagnostic basis is provided for the diagnosis of traffic safety risks and the prediction of potential traffic accidents.     

Economic effects of air transport market liberalization in Africa

Although the aviation industry is increasingly becoming important for Africa’s economic development and integration, the ability of airlines to access foreign markets remains hindered by restrictive regulatory policies. Attempts have been made to fully liberalize the intra-African air transport market. Except for general assertions about the merits/demerits of liberalization, our empirical understanding of the welfare effects of such polices in Africa remains rudimentary. This study empirically measures the economic effects of air transport liberalization, mainly on two supply side variables: fare and service quality, measured as departure frequency. The empirical models evaluate how air fares and departure frequency respond to measures of openness in air services agreements, while controlling for other determinants. The results show up to 40% increase in departure frequency in routes that experienced some type of liberalization compared to those governed by restrictive bilateral air service agreements. Furthermore, there is a relatively larger increase in departure frequency in routes which experienced partial liberalization compared to fully liberalized ones. This can be explained by the diminishing marginal effect of progressive liberalization on departure frequency. While the effect of liberalization is substantial in improving service quality, there is no evidence of its fare reducing effect.     

Design and evaluation of railway corridors based on spatial ecological and geological criteria

Transport infrastructure is closely linked to several sustainability issues of main policy relevance, and significant impacts on biodiversity as well as resource use and construction costs relate to the corridor design and location in the landscape. The aim of this study was to develop methods for railway corridor planning, in which corridor design and location would be based on important ecological and geological sustainability criteria. The method, an MCA framework including both spatial and non-spatial MCA, was demonstrated on a railway planning proposition in an urbanising area north of Stockholm, Sweden. Alternative spatial alignments for 6 railway corridors were derived based on criteria representing biodiversity, resource efficiency and costs, developed from ecological and geological knowledge, data and models. The method identified a study area specific positive synergy between ecological and geological sustainability criteria. The evaluation part of the methodology could furthermore identify uncertainties in the input data and assumptions and conflicts between ecological criteria. In order to arrive at a well-informed decision support system, the criteria as well as the decision rules employed could be further elaborated. Other relevant sustainability issues would also need to be integrated, such as cultural landscapes, recreation, and other ecosystem services. Still, arriving at a corridor design informed by the ecological and geological conditions in the planned area, as demonstrated by this study, could improve the sustainability performance of transport infrastructure planning.     

A behavioural comparison of route choice on metro networks: Time,transfers, crowding,topology and socio-demographics

Understanding travellers’ behaviour is key element in transportation planning. This article presents a route choice model for metro networks that considers different time components as well as variables related to the transferring experience, train crowding, network topology and socio-demographic characteristics. The route choice model is applied to the London Underground and Santiago Metro networks, to make a comparison of the decision making process of the users on both cities. As all the variables are statistically significant, it is possible to affirm that public transport users take into account a wide variety of elements when choosing routes. While in London the travellers prefer to spend time walking, in Santiago is preferable to spend time waiting. Santiago Metro users are more willing to travel in crowded trains than London Underground users. Both user groups have a similar dispreference to transfers after controlling for the time spent on transfer, but different attitudes to ascending and descending transfers. Topological factors presented on a distorted Metro map are more important than actual topology to passengers’ route choice decisions.     

Contrasts between utility maximisation and regret minimisation in the presence of opt out alternatives

An increasing number of studies of choice behaviour are looking at Random Regret Minimisation (RRM) as an alternative to the well established Random Utility Maximisation (RUM) framework. Empirical evidence tends to show small differences in performance between the two approaches, with the implied preference between the models being dataset specific. In the present paper, we discuss how in the context of choice tasks involving an opt out alternative, the differences are potentially more clear cut. Specifically, we hypothesise that when opt out alternatives are framed as a rejection of all the available alternatives, this is likely to have a detrimental impact on the performance of RRM, while the performance of RUM suffers more than RRM when the opt out is framed as a respondent being indifferent between the alternatives on offer. We provide empirical support for these hypotheses through two case studies, using the two different types of opt out alternatives. Our findings suggest that analysts need to carefully evaluate their choice of model structure in the presence of opt out alternatives, while any a priori preference for a given model structure should be taken into account in survey framing.     

Impact of service network topology on air transportation efficiency

Each stakeholder in the air transportation system has a different perspective on the performance efficiency metrics, making analysis of system-wide design options very difficult. This paper uses topological structures of service networks to examine trade-offs between efficiency metrics established around the passenger, airline, and air navigation service provider perspectives. The findings indicate that the scale-free type topologies are preferred under most of the metrics. However, with enough density, random topologies become more appealing with its high robustness feature and performance comparable to scale-free.     

A multi criteria decision analysis technique for including environmental impacts in sustainable infrastructure management business practices

This paper presents a decision analysis technique to allow highway agencies to assess the tradeoffs between costs, condition and energy consumption. It is shown how the entire feasible solution space can be evaluated between multiple stakeholders with differing values to assess the desirability of the outcomes resulting from infrastructure management decisions. Furthermore, an example network-level analysis is presented using data from the Virginia Department of Transportation. The example analysis clearly shows a tradeoff between the most cost effective outcomes (i.e., minimizing the cost divided by the condition) and the outcomes where the energy consumption is minimized, and how decision analysis should account for this tradeoff. The results of the method presented in this paper show that various pavement management alternatives can be represented in terms of desirability, and that this desirability can assist the decision maker with making decisions about performance goals and targets.     

Computer aided design of the operation and the track layout of the passenger railway stations: interactive—graphic model AFAIG

This paper presents a software model for the planning of passenger railway stations. The aim of this model is the elaboration of operation programs within stations, and the evaluation of projects for the track layout.

This model allows the planner to elaborate interactively an operation program, through a man‐computer dialogue, in a way similar to the manual procedure with which he is familiar. On the other hand, the model includes an optimization algorithm which can be used to automatically set routes to the trains, through the station.     

基于TAN网络的地铁区间与车站施工事故致因分析

为解决不同类型的地铁施工事故关键致因识别，以便于支持事故相关方在风险分析、预防和控制进行决策的问题。在收集国内2011—2021年间发生的202起事故报告数据的基础上，采用树增强朴素贝叶斯（tree augmented naive, TAN）和EM算法，从事故经过、直接原因、间接原因3个角度分别对事故报告进行统计处理、风险指标提取及合并、风险指标筛选、模型图形结构构建、模型参数确定，并采用GENIE软件训练数据建立最终分析模型。贝叶斯模型分析结果表明： 1）通过正向推理明确不同类型事故的关键致险因素，并对各风险因素引发事故的总体影响程度进行重要度排序； 2）通过反向诊断说明所建模型在不同风险因素组合情境下对风险预测的决策支持作用； 3）10折交叉验证证实了模型的有效性。     

基于决策树的异常电池分类方法

提出了一种基于决策树算法的异常电池精准定位和分类方法，帮助人们在电池维修或更换时能够迅速确定故障单体的位置和类型，从而实施准确的维修更换方法，提高故障处理的效率。搭建电池仿真模型获取异常电池的充放电循环数据；以电压数据为基础，训练用于异常电池分类的决策树算法，使用试验数据和云端实车数据对构建的模型进行验证。验证结果表明，该方法能够准确判断异常电池单体在电池组中的位置和异常类型。在不同验证数据上，该方法的分类准确率高达98%以上，能够有效筛选出动力电池组中的异常电池。该结果说明了提出的决策树算法在动力电池异常分类中的有效性和准确性。