I can’t believe your attitude: a joint estimation of best worst attitudes and electric vehicle choice

The number of conventionally fuelled motor vehicles in use is increasing worldwide despite warnings about finite fossil fuel and the detrimental impacts of burning such fuels. While electric vehicles, the subject of much research, generate far less emissions and offer the potential for power from renewable sources, they are yet to significantly penetrate the market. Tangible barriers such as price and vehicle range still exist, but consumer attitudes also drive behaviour. This paper examines attributes in a framework relatively new to transportation and energy policy; best–worst scaling. This method is widely considered an improvement over traditional methods of eliciting attitudes and beliefs, where respondents select attitudes they find best or worst from a set of attitudinal statements. To avoid potential endogeneity bias, we jointly model attitudes and choice for the first time with best–worst data. It is found that energy crisis, air quality and climate change concerns influence behaviour with respect to vehicle range and that travel behaviour change and forms of government incentives are needed influences on behaviour with respect to vehicle emissions. It is argued that correctly modelling attitudes reduces the error term of the vehicle choice model and provides policy makers with an improved lens for assessing behaviour. Additionally, the methods described within can easily be adapted to other policy scenarios.     

Incorporating insights from signal optimization into reservation-based intersection controls

Reservation-based intersection control for autonomous vehicles has the potential to make greater use of intersection capacity. Indeed, previous studies on the first-come-first-served (FCFS) policy (which prioritizes vehicles by order of their reservation request) have shown improvements over optimized signals. However, in certain situations, such as asymmetric intersections, FCFS easily performs worse than signals. To address this issue, we propose two new reservation policies, WEIGHTED and PHASED. WEIGHTED weights vehicle delay by signal timings, and PHASED simulates a signal but allows red phase turning movements that will not cause a collision. We test these policies on a city network and an arterial bottleneck intersection subnetwork and show that PHASED performs better than WEIGHTED in some scenarios, and vice versa. Furthermore, we show that using a combination of PHASED and WEIGHTED can perform better than using either one alone for the entire network. Results show that these policies provide effective and easily implemented alternatives to FCFS for reservations.     

150 mL以下摩托车达到欧Ⅲ排放标准面临的技术挑战和解决方案

中国摩托车市场中,排量150 mL及以下采用四冲程单缸发动机的车型占主导地位.这种车由于成本低,使用、维修便利,适合城乡使用,已成为非常流行的基本交通工具.欧洲将于2006年开始实行针对摩托车的欧Ⅲ排放标准,中国将在2008年实施等同该标准的第3阶段标准.摩托车生产企业和正在开发高技术含量摩托车的企业都面临着严峻的技术挑战--必须使他们的产品符合新排放标准要求,同时还必须在成本和功能上保持对顾客的吸引力.     

Multimodal route choice in maritime transportation: the case of Korean auto-parts exporters

Global offshoring has increased the need for transport of half-finished goods and components, along with finished goods. The auto-parts industry in Korea has also entered the global market as Korean car manufacturers have started to build overseas factories. Maintaining cost competitiveness by minimising total logistics costs will thus be a critical strategy for the industry. This research compares the total annual costs of four feasible transport routes from Korea to the US using the inventory-theoretic model, which encompasses direct transport costs, in-transit carrying costs, and warehouse inventory costs. We apply this model to real transport data collected from a Korean auto-parts company. A static analysis shows that inventory costs can play a decisive role in altering the cost competitiveness of different routes. In addition, sensitivity and scenario analyses with changes in variables and the market situations reveal that the cost structure of each route plays an important role in determining their relative cost competitiveness in varying market conditions.     

Ground-truthing social vulnerability indices of Alaska fishing communities

Abstract

Community vulnerability is increasingly evaluated through quantitative social indices, typically developed using secondary data sources rather than primary data collection. It is necessary to understand the validity of these indices if they will be used to inform policy and decision making. This paper presents a ground-truthing effort to validate quantitative indices that characterize the well-being of Alaska fishing communities. We utilized ethnographic data collected from 13 representative communities and a capital assets framework to ground-truth the indices, in which qualitative ranks of vulnerability were compared against quantitative indices. The majority (73.8%) of ranks were in complete or moderate agreement and the results indicate that most of the indices are representative of community vulnerability; yet some variables utilized to create the indices could be modified to better reflect realities in Alaska. Indices of commercial fishery engagement and reliance appeared to be more reliable than socio-economic indicators, particularly for smaller fishing communities. We also confirmed that the indices do not capture political, or ecological factors that affect levels of community vulnerability. We conclude that quantitative indices of community vulnerability are useful rapid assessment tools; however, they should be validated, and complemented with ethnographic data prior to their implementation as policy making and management tools.     

Combining technology development and behaviour change to meet CO2 cumulative emission budgets for road transport: Case studies for the USA and Europe

Global temperature rise over the long term will be proportional to the total amount of CO₂ emitted. Any given probability of exceeding a targeted maximum temperature rise implies a maximum limit on the cumulative total of CO₂ that can be emitted: a CO₂ “budget”. This paper describes an approach to modelling cumulative emissions from light and heavy duty road transport from the present to 2050, focussing on the USA and Europe, and comparing the potential impacts of a range of technological and behaviourally-based abatement measures with such cumulative emissions budgets.The model shows that abatement measures would have a lower effect on cumulative emissions from 2000 to 2050 than on annual emissions in 2050, so that focussing only on annual emissions could be misleading. It shows that technological developments would be insufficient on their own to enable Europe and the USA to meet CO₂ budgets for road transport. Behavioural changes, which potentially can be implemented much sooner, would be essential too. There is potential to keep European light duty emissions very close to CO₂ budgets, and US light duty emissions not far above the least restrictive budget, but the model predicts that heavy duty emissions in both regions are likely to exceed their CO₂ budgets. Deeper emissions reductions in other regions and sectors will be needed to compensate for this. Timing would be critical: for the greatest impact, behaviour change policies and interventions would need to be applied early and deeply.     

Occupational mortality among British merchant seafarers (1986-1995)

The decline of the British merchant fleet in recent years has led to an increasing proportion of British seafarers taking employment in flags of convenience and other foreign-registered vessels. It is then a matter of some importance as to whether the British seafarers who serve in foreign ships are at greater risk of mortality and, when fatalities do occur, whether the deaths are appropriately investigated. Using information obtained from files at the Registrar General for Shipping, the Marine Accident Investigation Branch and many Coroners, it is evident that British seafarers serving in foreign vessels were, during the study period 1986-1995, at greater risk of mortality through work-related accidents, suicides and unexplained disappearances at sea. Those serving in the British fleet, however, died more frequently through illnesses, and through off-duty accidents and drowning. When fatalities occurred in the British fleet, the relevant log book extracts were routinely deposited with the appropriate British authorities; for deaths in FOC vessels these documents were rarely forthcoming. While the deaths of British seafarers were investigated in the large majority of cases, foreign flag state authorities seldom conducted inquiries; it was the British authorities who usually conducted the investigations.     

The authors in this issue

Cambridge is a small free standing city in the UK with a population of 105 000. In recent years it has endured a worsening congestion problem essentially as a result of employment growth within the city and the narrow street layout. This is not a unique problem but one which is particularly acute in historic cities. In 1990, Congestion Metering was advanced, in addition to a number of other measures, as a means of managing traffic demand within the city. It has generated a great deal of interest internationally, particularly the field trial which took place in October 1993. This was the first time that any form of road pricing had been demonstrated practically in the UK. The aim of this article is to provide a review, establishing why the idea of Congestion Metering was originally considered and why, at least in the short to medium term, it is unlikely to be implemented in a Cambridge context. The process by which, if adopted, it is envisaged that Congestion Metering would be introduced is outlined, and the relative merits and potential weaknesses of such a demand management measure. Finally, the author considers the real problem of ‘public scepticism’ which needs to be addressed if Congestion Metering is to avoid the pitfalls which have bedevilled other road pricing schemes world‐wide.     

Lateral Dynamics of an Offroad Motorcycle by System Identification

An instrumented offroad motorcycle was run at a range of speeds in approximately straight lines whilst the rider excited its lateral dynamics by shaking the steering. Autoregressive models were fitted to the resulting multiple output time series data using system identification. The method allowed statistical estimation of state space models to represent the dynamics of an unstable or marginally stable vehicle under manual control. A symbolic algebra computer package was used to derive an analytical state space model to describe the lateral dynamics of the motorcycle. Results from the experiments and analysis compared well with respect to frequency, damping and modal shape of weave and wobble modes, frequency response and model order.     

Lateral dynamics of motorcycles towing single-wheeled trailers

A motorcycle towing a single-wheel trailer may provide useful transport for light cargo on narrow tracks and off-road use, particularly in rural areas of developing countries. Four designs of such trailers are described. Linear models are derived for the lateral dynamics of an off-road motorcycle towing this type of trailer straight ahead at constant speed. The trailers were tested behind an instrumented motorcycle. Linear autoregressive models were fitted to the experimental data using system identification techniques. Analytical and experimentally derived models largely agreed on frequency, damping and shape of the weave, wobble and trailer sway normal modes. The trailers made the motorcycle's steering heavier but the analytical models did not predict this. The location of the articulation axes between the motorcycle and the trailer were found to be critical for stability. The best trailer design handled well with loads up to 200 kg and speeds up to 70 km/h.