Impact of ITS measures on public transport: A Case study

Intelligent Transport Systems (ITS) have a wide range of applications. They range from the more traditional signal coordination system to concepts such as smart cars and smart roads. This paper describes transit‐based ITS measures in Singapore. The island‐state has plans to double the current 90 km rail network over the next ten years and has also implemented or committed to implement many ITS initiatives that impact upon the public transport systems. The aim of these investments is to achieve a high transit modal share using a comprehensive transit network. ITS measures that can promote this aim include: automatic vehicle location systems for buses and taxis, integrated transit fare systems using contactless smart cards, rail information systems, multi‐modal travel guides on Internet and electronic road pricing. The potential impacts of these measures are delay reduction, more comfort, productivity gain and better network accessibility. ITS measures do not necessarily add physical capacity to a public transport system but are excellent supporting measures to encourage the modal shift to transit, particularly if a quality transit system is already in place.     

Effect of wave boundary layer on sea-to-air dimethylsulfide transfer velocity during typhoon passage

A full-spectral third-generation ocean wind–wave model (Wavewatch-III) implemented in the South China Sea is used to investigate the effects of the wave boundary layer on the drag coefficient and the sea-to-air transfer velocity of dimethylsulfide (DMS) during passage of Typhoon Wukong (September 5–11, 2000) with a maximum sustained wind speed of 38 m s^− 1. The model is driven by the reanalyzed surface winds (1° × 1°, four times daily) from the National Centers for Environmental Prediction. It is found that the wave boundary layer evidently enhances (16.5%) the drag coefficient (in turn increases the momentum flux across the air–sea interface), and reduces (13.1%) the sea-to-air DMS transfer velocity (in turn decreases the sea-to-air DMS flux). This indicates the possibility of important roles of wave boundary layer in atmospheric DMS contents and global climate system.     

La logistique urbaine à l’épreuve du facteur 4

In this paper, we are putting forward a methodology and results from a simulation of different town development scenarios, aimed at reducing the impact of greenhouse gas production from the exchange of goods by 75%. The state-of-the-art scenarios are designed based on combining elements relating to recent planning work on town transport systems in France, and empirical results based on surveys and urban logistics modelling work. It shows a set of relevant determinants of potential changes in the formation of goods flows within the town. Based on the fact that, in France, more than half of the car-equivalent vehicle-km produced by the transportation of goods are as a result of households using their cars to go shopping, the scenarios are designed according to a systematic approach to urban mobility of goods and people. They bring together organisational aspects (changes to the urban goods movement system) and aspects of planning and land use, especially with regard to flow generators such as factories, warehouses, shops and households. The calculations, allowing the measurement of the impact of these scenarios on the production of greenhouse gases, are carried out using a model that combines the changes between economic production activities on the one hand, and the changes to household purchases on the other. As a result, organisational changes are proving to be an essential addition to a policy for increasing the density of the urban fabric.     

Using the sustainability footprint model to assess development impacts of transportation systems

A review of the sustainability literature reveals the lack of viable frameworks and management tools that can be used to accommodate both spatial and temporal variability in how stakeholder entities meet their sustainable development goals, taking into account the fact that different entities may need to pursue different priorities and also deal with different constraints and schedules at different stages of their development. This paper presents a sustainability footprint framework and model that may be used in analyzing the impacts of transportation and other infrastructure systems on regional sustainable development. A specific application of the framework is in the quality of life contributions that transportation systems may make to communities as a function of their impacts on natural assets that contribute inputs and absorb the byproducts of development. The application is illustrated in a case study that uses data from the Atlanta and Chicago Metropolitan Areas to demonstrate how this model may be applied in real life situations. The implications of this model for transport systems research, policy and practice are discussed. The value of this framework and model lie in introducing both spatial and temporal flexibility that may enable stakeholders with widely different priorities to reach consensus on interim goals for sustainable development to ultimately attain sustainability.     

Determinants of certified motorcycle helmet use among postal delivery riders at rural areas in Peninsular Malaysia

This study aims to identify the determinants of certified helmet use among postal delivery riders (PDRs) in rural areas of Peninsular Malaysia. A cross-sectional study was done among 269 PDRs from 50 postal distribution centres (DC) nationwide. Data collection was achieved through observation of the helmets and a questionnaire. The quality of the motorcycle helmets was determined by the presence of the certification label issued by the Standards and Industrial Research Institute of Malaysia (SIRIM). The response rate was 99.3%. The odds of full-shell helmets having the SIRIM label were 37.1 times more than that of the half-shell helmets. The odds of non-purchased helmets having the SIRIM label were 14.9 times more than that of the purchased helmets. The odds of expensive helmets having the SIRIM label were 4.4 times more than that for cheaper motorcycle helmets. The odds of helmets owned by riders without a previous crash history having the SIRIM label were 1.9 times more than helmets owned by riders with a crash history. Full-shell helmets with SIRIM standard certification, non-purchased helmets, helmet price of US$11.00 or more, and motorcycle riders without any previous crash history were determinants that contributed towards the use of a certified motorcycle helmet. Multiple logistic regression indicated that two variables significantly predicted the use of a certified motorcycle helmet among PDRs – helmet type and cost. An employer that provides the employees with full-shell motorcycle helmets with SIRIM standard certification label that costs at least US$11.00 and hiring motorcycle riders without any previous crash history gives a higher chance of compliance with standard certified motorcycle helmet usage.     

高速列车用轨道制动装置

在市场经济条件下，发展俄罗斯的高速铁路运输业是很迫切的任务。由于客车运行速度的提高，与其他形式的高速工具相比，即使2站间的运输距离很长，铁路运输的竞争力也在不断增强。然而，摆在面前的突出问题是要提高列车运行的安全性，解决这个问题，在很大程度上取决于制动系统的工作效率和工作稳定性。     

Monitoring long-term environmental change: Some lessons from Sullom Voe,Shetland Islands

The impact on the marine environment of the operation of the Sullom Voe Oil Terminal and its major port facility in the Shetland Islands has been monitored continuously for more than twenty-five years. The site of this very large terminal straddles a peninsula and the separation of the impact of the port on the sheltered west side (Sullom Voe) and the aqueous discharge from the terminal to the east, into the strong tidal current of Yell Sound, has proven to be advantageous. There are two types of monitoring, statutory (to comply with relevant legislation) and voluntary (to establish good practice and to examine a wider range of impacts e.g. island-wide ornithology). The latter function is undertaken by an independent advisory committee (SOTEAG). Over time, the nature and amount of voluntary monitoring has decreased in response to the long term evidence that both terminal and port operations are having little or no impact on a wide range of habitats and species. Voluntary monitoring also acts as an independent check on both compliance and other forms of environmental assessment. Although the terminal is now operating at less than half its peak capacity, this does not mean that there has been apro-rata decrease in monitoring activity.     

An iterative group-based signal optimization scheme for traffic equilibrium networks

This paper presents an iterative scheme for a combined signal optimization and assignment problem, using a traffic model from the well-known procedure TRANSYT. The signal settings are optimized by means of a group-based technique, in which the signal timings are specified by the common cycle time, the start time and duration of the period of right of way for each signal group in the network. The optimization problem was formulated as an integer program and solved by a set of heuristics. Given the optimized signal settings determined from the group-based technique, a path-based assignment algorithm is employed to obtain the equilibrium traffic pattern using the sensitivity information for TRANSYT model and a Frank-Wolf method. Based on the equilibrium flow pattern, the group-based optimization algorithm is then used to determine a better set of signal timings. The procedure is repeated until certain convergence criteria are satisfied. A numerical example is employed to demonstrate the benefits obtained from this iterative scheme. Encouraging results are obtained.