Measuring the performance of intermodal freight terminals

As the interface point between road and rail, intermodal freight terminals (IFTs) are critical elements in the total freight distribution chain. This paper addresses the twin objectives of reducing freight transport costs and improving customer service by putting forward a number of indicators designed to measure the performance of IFTs. Each of the three major performance areas, namely customer service, operational efficiency and terminal productivity are discussed in detail.

A methodology is put forward which enables operating strategies to be evaluated. Computer simulation is used in order to arrive at strategies which reduce operating and capital costs and satisfy customer service requirements. The simulation model outputs include performance measures related to customer service such as mean waiting times required for loading and unloading of containers, as well as productivity measures of terminal operations such as lifting equipment utilisation.     

Historic Monuments Threatened by Coastal Hazards at Boca do Rio,Algarve, Portugal

The coastal stretch of Boca do Rio, western Algarve, Portugal, is experiencing shoreline retreat. Roman ruins are located along the beach section of the coast, and a 17th-century fort is positioned over the cliff section. Both historic monuments are being destroyed by erosion but need to be protected due to their heritage status. Aerial photograph analysis was used to define the evolution of the coast for the period 1945–2001. Shoreline retreat of 0.3 m/year was measured for the sandy coast and 14 mass movements in the cliff face were identified. Considering the rate and style of shoreline evolution, several types of management scenario were evaluated, with the favored measures being the removal of the Roman ruins to a museum and the relocation of the fort inland.     

Fast Tool for Structural Monitoring of a Pier After Impact of a Very Large Vessel Using Ambient Vibration Analysis

Operational modal analysis is a non-destructive structural investigation that considers only the loads resulting from service conditions. This approach allows t...     

Integrating geographic information systems into transit ridership forecast models

Researchers have produced sophisticated modal split and transit demand models, including forecasts that are sensitive to the level of service. However, little effort has been made to integrate these models into corridor studies and route alignment analyses since (a) re-routing is itself an extremely complex modeling task, and (b) the results of the demand models are presented in tabular form with no facility to visualize spatial patterns and relationships that, if recognized, would aid in the routing tasks. GIS tools can be used, together with the demand models, to identify both clusters of city blocks that house families with certain socioeconomic characteristics and potential trip destinations conducive to transit use. In other words, GIS tools can be used to better measure some of the factors that are needed by transit demand models. The results of these models can be displayed graphically, enabling analysts to target places needing improved service, evaluate route re-alignment alternatives, and operate more efficient and effective bus lines. This paper examines how a particular class of model used by transit agencies for estimating ridership can be integrated with GIS tools in order to facilitate such analyses. It also explores the effects of visualization of routes, demographics, and employment data on the process of designing route alignments with better targeting of high transit ridership areas. This paper is part of a research project sponsored by the Region One University Transportation Center, at MIT.     

Transit Users’ Route‐Choice Modelling in Transit Assignment: A Review

Abstract

This paper reviews the main studies on transit users’ route choice in the context of transit assignment. The studies are categorized into three groups: static transit assignment, within‐day dynamic transit assignment, and emerging approaches. The motivations and behavioural assumptions of these approaches are re‐examined. The first group includes shortest‐path heuristics in all‐or‐nothing assignment, random utility maximization route‐choice models in stochastic assignment, and user equilibrium based assignment. The second group covers within‐day dynamics in transit users’ route choice, transit network formulations, and dynamic transit assignment. The third group introduces the emerging studies on behavioural complexities, day‐to‐day dynamics, and real‐time dynamics in transit users’ route choice. Future research directions are also discussed.     

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本文提出一种用于评价公路－铁路联合运输货运枢纽选址方案的整数模型。模型中的四个主体为：货运枢纽经营者、交通运输网络设施规划者、客户、社会公众。介绍了可使全局目标优化的基于主体建模方法(ABM)在货运枢纽选址中的应用。最后，本文以澳大利亚昆士兰州东南部的货物联合运输枢纽为例，介绍了其原始选址过程、个体目标函数测试及基于主体的模型设计过程。     

PPPs — True Financial Costs and Hidden Returns

The cost of using private finance is at the centre of the public private partnerships (PPPs) debate, but until now most works considered only the direct financial costs such as the loan interest rate and the shareholders return on equity and were based on various secondary sources. This paper focuses on seven shadow toll deals closed in Portugal between 1999 and 2002 and reports the financial costs of the PPP model considering also the associated transaction costs and is based on detailed information included in each concession's financial base case. The transaction costs include financial costs such as banking fees, due diligence costs and the impact of all cash distribution traps, such as reserve accounts or minimum-level of debt ratios. The PPP financial costs were then compared with the costs arising from raising public debt through a government or a public agency bond. Our analysis shows that the PPP ‘true' financing costs are, on average, 370 basis points above the cost of raising public debt and that the ‘transaction costs' account for around 40% of that financial premium.     

Micro-simulation modelling for traffic safety: A review and potential application to heterogeneous traffic environment

This paper critically reviews micro-simulation modelling applications for traffic safety evaluation with respect to the use of different simulation tools, the application of surrogate safety indicators under different aspects of road environments and crash considerations. General input variables used to develop the models; key parameters for crash prediction; and calibration and validation approaches are explored in the paper. The strengths and weaknesses of used simulation packages for traffic safety evaluation are also pointed out. Moreover, recent advancements in the development and application of traffic safety micro-simulation model for safety assessment are also discussed.Despite having a number of studies, there is still a significant void in the development and application of simulation model to evaluate traffic safety of non-lane based heterogeneous traffic environments that predominate in many developing countries. The paper assessed the potential application of traffic safety micro-simulation model in heterogeneous traffic environments. Finally, a number of potentially fruitful future research directions are highlighted.     

Rail track infrastructure ownership: investment and operational issues

As privatisation of railway systems reach the political agendas in a number of countries, the separation of track infrastructure from train operations is seen as providing the vehicle which will improve profitability within the rail industry. This paper deals with three main issues related to such separation within a freight railway focus, namely: investment appraisal; track standards and maintenance; and train operating performance. The conflicts of interest between the owners of track and their client operators are discussed in detail. Costs related to track capacity and congestion need to be taken into account, given that additional trains are likely to lead to increased risk of delays to existing services. The paper discusses the use of a travel time reliability model to estimate the additional costs imposed on the system through the introduction of specific train services.It is concluded that investment in individual elements of railway infrastructure must be integrated with the overall financial and customer service strategies of both operators and owners. As an alternative to current practices, a hybrid model of track ownership is put forward here. Under such a model, a joint-venture company with equity from the main ÒplayersÓ would be owner of track. This would allow some of the benefits of vertical integration to be retained, whilst providing fair access to new operators.     

Using Bus Rapid Transit to Mitigate Emissions of CO2 from Transport

Abstract

This article investigates the role of bus rapid transit as a tool for mitigation of transport‐related carbon dioxide (CO₂) emissions. We analyse a Quality Bus Corridor (QBC) implemented in Dublin, Ireland, in 1999 and estimate CO₂ emissions associated with differing levels of bus priority for the period 1998–2003 and for the Kyoto commitment period (2008–12). Associated monetary values are established using CO₂ prices from the European Union Emissions Trading Scheme. We find that, in the absence of a QBC, peak‐time emissions for our sample population would have been 50% higher than in the factual scenario. For the Kyoto commitment period, we find the median value of the policy implementation to be in the region of [euro]650 000.