Travel patterns in Dutch metropolitan cities: The importance of external trips

Using a variety of data sources, decentralisation of population and employment in four Dutch urban areas (Amsterdam, Rotterdam, The Hague and Utrecht) over the last 20 years, is analysed. It is found that suburbanisation, plus an ever growing car share, has increased the number of external journeys related to the metropolitan cities enormously. With the use of the 1982 National Travel Survey, current travel patterns in and around the metropolitan cities are studied: the importance of external trips for urban transport planning shows clearly. They account for about half the number of city related car trips, and for nearly three quarters of the total vehicle kilometres of travel within the city.(requests for reprints)     

The seafaring labour market in Brazil

The most recent reports on the supply and demand for seafarers suggest that there is an increasing lack of officers for the expanding world's merchant fleet. With a focus on Brazil, this paper discusses a particular seafaring labour market highlighting specific challenges that need to be overcome. The paper looks into the current condition of the imbalance in Brazilian seafaring labour market as well as the prospects for merchant marine officers from the only two maritime schools in the country. Key issues on demand forecast and supply expectation, policy amendment, promoting maritime career, sea career commitment and maritime career empowerment are discussed to illustrate possible means to overcome the imbalance.     

Kiribati seafarers and German container shipping

This article discusses the employment of Kiribati seafarers on German owned and flagged shipping. The authors examine the origins of the German shipping industry sponsored training and recruitment programmes on the Kiribati atolls. The implications of the creation of a manorial ‘internal’ labour market for German container shipping in the South West Pacific is assessed. The impact of labour participation in the international shipping industry on Kiribati's former fisherfolk is also examined.     

Implementing Road User Charging: The Lessons Learnt from Hong Kong,Cambridge and Central London

Abstract

This paper studies the possibility of increasing shipping of fruit and vegetables from Almería (southeast of Spain) to Port Vendres‐Perpignan (southeast of France). Almería is one of the areas of vegetables production largest in the world and Perpignan is one of the most important customers of Almería. After analysing the potential volume of shipping, we estimate a mode choice model which allows us to study the sensitivity of final clients (horticultural operators) to future change in the variables which condition the choice between transport by sea or by land. This will also help us to calculate the market share of each system as a function of foreseeable change in the variables.     

预应力CFRP板加固钢板受拉疲劳性能试验研究

为较好地预测预应力碳纤维材料(CFRP)板加固钢结构的疲劳性能,采用考虑有效应力强度因子幅的Pairs公式,分析了粘贴预应力CFRP板加固钢板的疲劳裂纹扩展行为.通过粘贴CFRP板的含中心孔的预制裂纹钢板的疲劳试验,分析了应力比、CFRP板刚度、预应力及粘结胶性能等因素对疲劳裂纹扩展的影响.试验结果表明:加固后结构的疲劳寿命提高16倍以上,疲劳寿命的理论分析结果偏于保守;预应力是疲劳寿命的主要影响因素,而CFRP板和粘结胶性能的影响有限;应力比埘疲劳寿命的影响很大,因此,对交通荷载的正确预估是加固能否取得成功的基础.     

The process of capital investment at US public portst

It is virtually impossible for a US public port authority to be totally proactive in its behaviour since there are too many major factors that affect its future that cannot be controlled or even anticipated by the port staff. Conversely, it is also virtually impossible for a public port authority to be totally reactive since the time window between decision and implementation often exceeds the time window of opportunity. For a public port authority to maintain long-term viability, it must constantly review the facilities it owns, the services it offers, and the source of the revenues it generates. This on-going review should determine how well the Port is adhering to its mission and accomplishing its goals and objectives as set out in the Port's strategic plan. Today, a major management challenge for any viable Port is prioritizing goals and maintaining a policy that ensures clear focus on the highest priority goals. Determining priorities amongst capital projects should be high on the list of any public port authority. This paper provides an overview of the decision-making processes used by American public port authorities in evaluating new capital projects and, we hope, an insight into processes for determining the desirability of expanding, contracting, or terminating present facilities and services.     

Systematic training for maritime transport managers

Providing effective training for managers in the maritime and ports sector in developing countries has proven to be a daunting task. Initial attempts by the United Nations Conference on Trade and Development (UNCTAD) in the 1970s led to the development of senior port manager residence courses in Sweden. However, Given the vast numbers of managers needing training a more eficient method was required. Using the systematic training techniques pioneered by the International Telecommunications Union, UNCTAD, in the 1980s initiated two parallel programme: Trainmer (Training development in Maritime Transport); and IPP (Improving Port Performance). Both of these programmes demonstrated considerable success in terms of the numbers of maritime and port managers receiving training opportunities. Increased cooperation amoungst international agencies providing training programmes should result in improved transport management training in the 1990s, lrading to increased efficiences in port and related transport systems.     

Signalized intersections with variable flow rates: II A model for delay estimation

This second part of our work develops a model for delay estimation at intersections whose traffic signal controls are continuously being updated. Generally, these traffic signals are centrally controlled. The foundation for the delay estimation model is based on a queuing theory model called “Preemptive resume discipline for M/G/1 with two priority levels.” This queuing model assumes that two customers arrive at acertain point by a Poisson arrival process, and that one customer has service priority over the second customer. The analogy for the case of intersection control is that the preferred customers are the red lights and the secondary customers are the vehicles. In order to adapt the model to the realistic behavior of vehicle traffic at continuously adjusted signals, components are derived to modify the model. The simulation results of the first part of this work are used to calculate adjustment factors that fairly accurately reproduce the simulated delays. This gives rise to the advantage of using in practice a closed mathematical model, in particular when trying to optimize the operation of signalized intersections at the network level.     

Investigating the predictive performance of computational process activity-based transportation models

The aim of this paper is to achieve a better understanding of computational process activity-based models, by identifying factors that influence the predictive performance of A Learning-based Transportation Oriented Simulation System model. Therefore, the work activity process model, which includes six decision steps, is investigated. The manner of execution in the process model contains two features, activation dependency and attribute interdependence. Activation dependency branches the execution of the simulation while attribute interdependence involves the inclusion of the decision outcome of a decision step as an attribute to subsequent decision steps. The model is experimented with by running the simulation in four settings. The performance of the models is assessed at three validation levels: the classifier or decision step level, the activity pattern sequence level and the origin–destination matrix level. The results of the validation analysis reveal more understanding of the model. Benchmarks and factors affecting the predictive performance of computational activity-based models are identified.