The role of public authorities

Advances in information technology and telecommunications are opening up the possibility of transforming the capture, application and dissemination of information on transport operations and road traffic, at the same time as growing congestion makes accurate and timely information more valuable than ever to users and managers. Because of open access to road networks, public authorities are bound to intervene in the field of travel information: in the provision of infrastructure, the handling of the information, the licensing of services, and the regulation of users affecting safety or social well-being. The paper discusses these rôles and the levels at which they may be exercised, with particular reference to standardisation issues in Europe and internationally.     

Evaluation of public transport: Method for application in open planning

This paper discusses a method to evaluate scheduled, fixed-route public transport. One major evaluation criterion in the method is total travel time, subdivided into walking time, waiting time, time on vehicle, transfer time, and concealed waiting time. The other major criterion is costs incurred by a given supply of transport. In contrast with conventional methods, this method operates with real measures, i.e. real location (instead of traffic zones), real time (instead of average travel time), and real costs (instead of proxy-costs). The purpose is to produce relevant and easily understandable results suitable to open planning, for instance planning with citizen participation. Five examples of application of the method are given: (1) evaluation of changes in suburban bus services; (2) evaluation of geographical localities as regards public transport; (3) evaluation of circular bus routes; (4) evaluation of flexible work hours versus fixed work hours and, finally; (5) production of user information on transport service.The research on evaluation of public transport was carried out in collaboration between Aalborg Municipality and the University of Aalborg 1980–1981. It was funded by the Department of Education, the University of Aarhus, Aalborg Municipality, the University of Aalborg's Data Centre and the University of Aalborg. The translation of this summary paper from Danish into English was funded and carried out by the Transport and Road Research Laboratories, Crowthorne, England.The paper summarizes: Bent Flyvbjerg, Kjeld Kahr, Peter Bo Petersen and Johs. Vibe-Petersen (1981).Evaluation of Public Transport — Method for Application in Open Planning. Vol. I & II. Aalborg University Press, Aalborg, 402 pp. In Danish.     

A scenario approach to airport evaluation in remote communities: with particular reference to the Pilbara region of Australia

Coordinated development of aviation facilities and services is critical for geographically remote communities. Improvements in aviation capability can be assisted by an analytical base for determining the implications of alternative configurations of air services in terms of links to be served, airport/aerodrome investment, type of flight equipment and flight frequency. We outline a method for identifying airport supply configurations to meet air service demand to and from the Pilbara region of north-west Australia. The approach emphasises minimum levels of demand required from a community in order to justify provision of air services of a given scenario. The method is influenced by the paucity of data on demand in remote communities, and the consequent risk of relying solely on demand-side forecasts of patronage levels. It is therefore particularly useful in assessing transport systems associated with remote resource development projects which are notable for the rapidity of change which they can bring. The approach has relevance to a wide range of transport applications.     

Simplified and advanced modelling of traction control systems of heavy-haul locomotives

Improving tractive effort is a very complex task in locomotive design. It requires the development of not only mechanical systems but also power systems, traction machines and traction algorithms. At the initial design stage, traction algorithms can be verified by means of a simulation approach. A simple single wheelset simulation approach is not sufficient because all locomotive dynamics are not fully taken into consideration. Given that many traction control strategies exist, the best solution is to use more advanced approaches for such studies. This paper describes the modelling of a locomotive with a bogie traction control strategy based on a co-simulation approach in order to deliver more accurate results. The simplified and advanced modelling approaches of a locomotive electric power system are compared in this paper in order to answer a fundamental question. What level of modelling complexity is necessary for the investigation of the dynamic behaviours of a heavy-haul locomotive running under traction? The simulation results obtained provide some recommendations on simulation processes and the further implementation of advanced and simplified modelling approaches.     

火线驰骋

全新的梅赛德斯C63 AMG和雷克萨斯IS F信誓旦旦,扬言要瓜分顶级豪车的市场。我们将它们同宝马最新的4门M3和目前该车系的佼佼者Audi RS4放到一起同场竞技,看看哪一台可以让驾驶者最为吃惊。     

Microscale variability in the distributions of large fluorescent particles observed in situ with a planar laser imaging fluorometer

It has been known for decades that particle-size and biomass spectra show regular patterns in the ocean, and that these patterns often show systematic variations with other properties such as total biomass, nutrient concentration, season, and distance (both vertical and horizontal). The recent finding of the ubiquitous nature of layers of phytoplankton < 1 m thick prompted us to explore the fine- and microscale vertical variations of size- and fluorescence-abundance spectra in the ocean. Using a two-dimensional planar laser imaging system mounted on a free-falling platform, we quantified the properties of large fluorescent particles ( 20 μm–2 cm) through the water column, obtaining images every 10–30 cm. These images showed systematic relationships of the spectral properties to total chlorophyll: increased proportions of the smallest particles at high chlorophyll concentrations, and a lengthening of the spectral size range at high total chlorophyll concentrations (more large particles at high chlorophyll concentrations). Further, we observed significant variations of the spectral properties over scales of 1 m and less, and recorded the frequent occurrence of unusual layers of large particles. Our new instrument, which is sensitive to thin layers of enhanced phytoplankton biomass, shows the planktonic community to be highly structured vertically on scales of 1–2 m, particularly within the DCM.     

Low-fi simulation of bridge team communication

The paper compares the pedagogical advantages of two simulation types used for training verbal maritime communication. It tests the hypothesis that “low-fi” simulation using online web conference software, specifically ‘chat’ or messaging, is a valid complementary tool for the instruction of Maritime English and full-mission simulation. Based on a series of exercises involving multi-national and multi-lingual students, various linguistic patterns are determined and compared to audio recordings of full-mission simulation. Probability of superiority effect sizes is computed to quantify the observed effects. The findings corroborate the proximity of language patterns found in low-fi and full-mission simulation. Pedagogical implications are discussed, and future research possibilities are outlined.     

The regulatory cycle stalled? An assessment of current institutional obstacles to regulatory reform in the provision of road-based public transport in Cape Town, South Africa

Wide-ranging and ambitious proposals for the comprehensive transformation of public transport systems in major South African cities, including Cape Town, have now been in play for a decade or more since the country’s post-apartheid transition. To date, progress in implementing such proposals has been, at best, much delayed and, in Cape Town, appears to have stalled, and may now be significantly compromised. This paper draws on aspects of the concept of regulatory cycles in the bus transport sector to explore some of the key factors which have given rise to this situation, focusing primarily on obstacles embedded in the present institutional framework which governs the provision of road-based public transport in the city. It specifically identifies difficulties in establishing an appropriately mandated and resourced agency at the local level to drive forward the transformation project and the sustained opposition of existing, largely ‘self-regulated’ minibus-taxi operators as key factors which have obstructed the introduction of the proposed regime of ‘regulated competition’. A tentative conclusion is offered to the effect that perhaps a partial or ‘hybrid’ transformation of the public transport system may be the best - and, indeed, possibly the most appropriate - outcome of the transformation process that can be anticipated under the present and foreseeable future circumstances prevailing in the city.     

Interpretation of cruise industry in a two-sided market context: An exploration on Japan

Two-sided markets are characterised by the presence of an intermediary and two groups of end-users. In the cruise market, cruise lines may play the role of intermediaries to connect the two end-users, viz. cruise passengers and cruise ports. Our research explored whether the cruise industry can be regarded as a two-sided market, starting with a theoretical modelling. The findings show that cruise lines might be hybrid intermediaries, selling their own ship-based products and services, while offering also a platform to enable the transaction between cruise passengers and cruise ports. This particular business model of a quasi-two-sided market is also reflected in the pricing scheme of cruise industry, whereby cruise ports charge an entry fee from cruise lines and port dues from cruise passengers. We illustrate an empirical analysis on the basis of the cruise market in Japan, and it provides a preliminary clue that the behaviours of cruise ports and cruise lines are consistent with our theoretical framework. The results are not convincingly significant due to data limitations, hence, the concept of a ‘two-sided market’ in the cruise industry call for further empirical research.     

A connected-vehicle-based dynamic control model for managing the bus bunching problem with capacity constraints

This paper describes a connected-vehicle-based system architecture which can provide more precise and comprehensive information on bus movements and passenger status. Then a dynamic control method is proposed using connected vehicle data. Traditionally, the bus bunching problem has been formulated into one of two types of optimization problem. The first uses total passenger time cost as the objective function and capacity, safe headway, and other factors as constraints. Due to the large number of scenarios considered, this type of framework is inefficient for real-time implementation. The other type uses headway adherence as the objective and applies a feedback control framework to minimize headway variations. Due to the simplicity in the formulation and solution algorithms, the headway-based models are more suitable for real-time transit operations. However, the headway-based feedback control framework proposed in the literature still assumes homogeneous conditions at all bus stations, and does not consider restricting passenger loads within the capacity constraints. In this paper, a dynamic control framework is proposed to improve not only headway adherence but also maintain the stability of passenger load within bus capacity in both homogenous and heterogeneous situations at bus stations. The study provides the stability conditions for optimal control with heterogeneous bus conditions and derives optimal control strategies to minimize passenger transit cost while maintaining vehicle loading within capacity constraints. The proposed model is validated with a numerical analysis and case study based on field data collected in Chengdu, China. The results show that the proposed model performs well on high-demand bus routes.