Classifying Ports for Efficiency Benchmarking: A Review and a Frontier-based Clustering Approach

Abstract

Port efficiency and port clustering are two aspects that have received different degrees of attention in the existing literature. While the actual estimation of port efficiency has been extensively studied, the existing literature has paid little attention to developing robust methodologies for port classification. In this paper, we review the literature on classification methods for port efficiency, and present an approach that combines stochastic frontier analysis, clustering and self-organized maps (SOM). Cluster methodologies that build on the estimated cost function parameters could group ports into performance metrics’ categories. This helps when setting improvement targets for ports as a function of their specific cluster. The methodology is applied to a database of Spanish port authorities. The dendrogram features three clusters and five outlier Spanish Port Authorities. SOM are employed to track the temporal evolution of Spanish Port Authorities that are of special interest for some reasons (i.e. outliers). Results show that use of a combination of cost frontier and cluster methods to define robust port typology and SOMs, jointly or in isolation, offers useful information to the decision-makers.     

Computing the cost of traffic congestion: a microsimulation exercise of the City of Antofagasta,Chile

Abstract

This paper computes the cost of traffic congestion in the city of Antofagasta in Chile. A microsimulation is implemented where all the agents of the system travel across the transport network. The congestion cost is computed through the aggregation of the opportunity cost of people waiting within the transport system, as a consequence of traffic congestion. Monte Carlo experiments produced an approximated congestion cost of US$1.02 million during a typical working day. Moreover, the simulation provides useful information about the average traveling time for the 14 districts of the city.     

工程项目在设计阶段的造价控制点

设计阶段的工程造价控制十分重要,必须认真做好。阐述造价控制的若干阶段和设计阶段对工程造价控制的重要性。详细论述设计阶段造价控制目标和造价控制方法,并提出若干注意事项。可供参考。     

Promoting Cycling for Transport: Research Needs and Challenges

Abstract

Near future travel-time information is one of the most critical factors that travellers consider before making trip decisions. In efforts to provide more reliable future travel-time estimations, transportation engineers have examined various techniques developed in the last three decades. However, there have not been sufficiently systematic and through reviews so far. In order to effectively support various transportation strategies and applications including Intelligent Transportation Systems (ITS), it is necessary to apply appropriate forecasting methods for matching circumstances in a timely manner. This paper conducts a comprehensive review study focusing on literatures, including modern techniques proposed recently, related to travel time and traffic condition predictions that are based on ‘data-driven' approaches. Based on the underlying mechanisms and theoretical principles, different approaches are categorized as parametric (linear regression and time series) and non-parametric approaches (artificial intelligence and pattern searching). Then, the approaches are analysed for their strengths, potential weaknesses, and performances from five main perspectives that are prediction range, accuracy, efficiency, applicability, and robustness.     

Route Choice Behaviour of Freeway Travellers Under Real-time Traffic Information Provision – Application of the Best Route and the Habitual Route Choice Mechanisms

Abstract

This paper investigates route choice behaviour on freeways between Taipei and Taichung in Taiwan under the provision of real-time traffic information. Two types of route choice selection rules (the best-route and habitual-route) are analysed using ordered probit models to identify the major influences on freeway travellers’ route choice behaviour. The level of service associated with each route is defined as a generalised cost saving (GCS) and specified non-linearly with a threshold inherent to travellers. The marginal (dis)utility thresholds in the ‘best’ and ‘habitual’ behaviour models are identified through a goodness-of-fit grid. The results confirm that the thresholds for changing the inertia behaviour of drivers should be larger than the ones for choosing the best routes. In addition, the drivers are more likely to choose either the best or the habitual routes once the GCS are greater than the identified threshold values.     

浅议市政工程全过程造价控制及重点

该文阐述了市政工程造价控制的全过程及重点,分析了造价人员在各阶段的工作内容和职责,并对未来提出了展望。     

公路项目质量保证成本估算模型构建与运用

为预估公路保证成本,进而规划、有效控制和适时拨付保证成本、指导各部门实践,在剖析国内外研究趋势基础上,引入公路项目失效函数理论,分析了失效因子与质量保证的关系;随后基于个体失效模式、可靠性、随机过程,构建了公路项目失效函数;并以某公路项目为例对长期质量保证下横向裂缝与车辙2个指标进行质量保证期期望维修成本和保证风险成本进行估算;以此为基础对政策制订、发包商的招标行为、承包商的投标与施工行为、质量保证资源协调控制进行了分析,最后对估算模型现实运用的扩展性进行了说明.     

城市轨道交通工程造价风险评估研究

城市轨道交通工程是一项投资大、建设周期长、社会影响大的大型工程项目,它存在很多风险因素。只有对这些风险因素进行科学的评估和控制,才能确保工程造价不会失控。介绍城市轨道交通工程的造价组成及其特点,在此基础上分析城市轨道交通工程的造价风险,最后从风险识别、风险分析、风险评价三个方面对工程造价进行了风险评估。     

高速公路施工项目成本标准化管理的措施与成效分析

高速公路施工项目成本决定着企业的经济效益,提高成本管理水平是提升高速公路项目经济效益和社会效益的重要途径。针对高速公路施工项目成本标准化管理问题展开讨论,分析了成本标准化管理的实施对策与实施途径,以期为高速公路项目成本管理提供可行的参考。     

工程造价与概预算定额的应用

投标策略是投标人经营决策的组成部分,指导投标全过程。影响投标的因素十分复杂,既要考虑自身优势和劣势,也要考虑竞争的激烈程度,还要分析投标项目的整体特点。因此,需要投标人认真研读投标文件指标要求、风险类型、材料价差及报价方法,尤其是概预算定额的运用直接影响到投标报价。