From theory to practice in road safety policy: Understanding risk versus mobility

This paper reviews theoretical issues surrounding transport safety modeling and the implications for road safety policy. The behavioral mechanisms that affect transport safety are typically not considered in safety modeling. These issues are discussed in the context of trade-offs between risk-taking, as perceived by travelers, and other mobility objectives and the attributes associated with them. This is an extension of other theoretical frameworks, such as risk compensation, and attempts to integrate some of the previous frameworks developed over the years. Various examples of behavioral adaptation to specific policies are discussed and linked to the framework. These issues are then discussed in the context of improvements to empirical work in this area and the linkage of theoretical frameworks to crash modeling, in particular the estimation and use of Crash Modification Factors. Conclusions suggest that there are many deficiencies in practice, from estimation of models to choice of effective policies. Progress is being made on the former, while the publication of practical guidance seems to have substantial lags in knowledge.     

Reasons for participating in formal employer-led carpool schemes as perceived by their users

Abstract

Carpooling, the process by which individuals share a private vehicle for a particular journey or journeys, has been undertaken both formally and informally for a great number of years. A variety of computational methods for undertaking the ‘ride-matching’ element for the formation of carpools have been developed and subsequently made into integrated tools to allow the formation of multiple carpools. Such tools are commonly used by both Local Authorities and employers who are looking to establish and operate their own formal carpool scheme, increasingly using a web-based interface.

The aim of this paper is to understand how users enrolled with employer-led carpool schemes perceive the importance of several different factors in their decision to participate. It is a further aim to determine the importance they attach to employer provided priority parking spaces. A survey-based approach investigates the perceptions of users from six different employer operated carpool schemes in the UK.

The paper suggests that saving money was perceived as the most important reason for an individual's decision to use a formal employer-led carpool scheme – even amongst carpool schemes where the employer provides significant incentives to participate. No regular access to their own vehicle and ‘more sociable travel’ were generally perceived as less important reasons to participate. For employers who offer priority parking to carpoolers, this was generally valued as important by participants, even when the employment location did not have significant parking pressures.     

Segmentation of paratransit users based on service quality and travel behaviour in Bandung,Indonesia

Using a data-set collected among paratransit users in Bandung, Indonesia, this paper explores the impacts of paratransit users' negative experiences and dissatisfactions with their paratransit usage pattern. Segmentation and ordered probit analyses are used to examine the impacts of users' opinions on service quality on their trip-making behaviour. The results indicate that users are divided into six segments – namely, the unlucky, the young user, the experienced, the adapter, the infrequent user and the captive. The results further indicate that paratransit users, especially women, perceive negative experiences related to on-time performance (departure and arrival time) and security issues related to vehicles. Despite these dissatisfactions and negative experiences, they are still likely to use paratransit as part of their daily life. Two paratransit market segments (the adapter and the captive) are also likely to result in more trips using paratransit. The study offers several strategies and recommendations that can improve the current paratransit system so that it can better serve local needs.     

俄罗斯“雄鹰号”新一代高速电动车组（待续）

“雄鹰号”高速电动车组的研制成功，标志着俄罗斯从此跻身世界高速列车生产国行列，本文详细介绍了“雄鹰号”的开发背景、设计思想、布置方案以及主要部件和系统的结构型式和技术性能等。     

Environmental changes and the responses of the ecosystems of the Yellow Sea during 1976–2000

The changes in the environmental features of the Yellow Sea during the last 25 years of the 20th century were studied using a set of seasonally monitored data along a transect (at 36°N) maintained by the State Oceanic Administration of China. The data included the ocean temperature (T), salinity (S) and biogenic elements, such as dissolved oxygen (DO), phosphorus (PO₄-P), silicon (SiO₃-Si) and dissolved inorganic nitrogen (DIN).The seasonal (summer and winter) values and the annual mean of these elements showed significant changes during the monitored period. Time series of T, S, DIN and N:P ratios exhibited positive trends, while those of DO, P and Si exhibited negative trends. During this period, the annual mean of T and DIN in the Yellow Sea increased by 1.7 °C and 2.95 μmol L⁻¹, respectively, while those of DO, P and Si decreased by 59.1, 0.1 and 3.93 μmol L⁻¹, respectively. In the 1980s, particularly in between 1985 and 1989, concentrations of P and Si dropped to near the ecological threshold for growth of diatoms. The N:P ratio increased from 4 in 1984 to over 16 in 2000. The climate trend coefficients, R_xt, for these time series are all above 0.43 with significance levels of 95%, except for salinity. The increases in T were consistent with the recent climate warming in northern China and the adjacent seas, i.e. the Bohai Sea and the East China Sea. The reduction of DO was probably attributable to the increase in T and decrease in primary production in these regions. The positive trend of DIN was mainly attributable to precipitation and partly to Changjiang River discharge. The negative concentration trends of P and Si were due to the decreases in their concentrations in seawater that flowed to the Yellow Sea from the Bohai Sea. As a result, N:P ratios greatly increased in the seawater of the Yellow Sea.Moreover, some important responses of the Yellow Sea ecosystems to the changes in physical variables and chemical biogenic elements were obviously displayed. These responses include strengthening nutrient limitation, decreasing chlorophyll a, primary production and phytoplankton abundance, succession of dominant phytoplankton species from diatoms to non-diatoms, changes in fish community structure and species diversity.     

Technical Note: Force Control in Electrohydraulic Active Suspensions Revisited

The inner loop control for the actuator force can be quite simply compensated by means of a correction term to the desired force signal at the input. The correction requires only a measurement of the actuator piston velocity and is employed to cancel the loop disturbance caused by the oil flow to the actuator. Although an additional time constant is introduced by the integration in the inner loop force control, the overall performance is nevertheless quite close to that of an ideal optimal system.     

接触网支柱电蚀保护装置的改进

为了对接触网支柱进行防电蚀保护,长期以来采用各种保护装置.对防电蚀保护装置的主要性能要求为:当轨道电路中存在牵引电流的情况下,装置必须工作可靠;在接触网短路情况下,装置应能正常动作.     

How much disruption to activities could fuel shortages cause? – The British fuel crisis of September 2000

In September of 2000 the UK experienced a blockade of oil refineries in response to rising fuel prices. These protests resulted in severe fuel supply disruptions that intensified over the course of about one week. During the peak of the crisis, travel activity by car was curtailed. This paper analyzes survey data collected about two months after the crisis utilizing the recent memory of respondents as to how they would expect this sort of disruption to affect their participation in daily activities. Specifically, we focused on a variety of non-discretionary and discretionary activities and examined what factors are associated with respondents expecting disruption to those activities. Statistical models were developed to analyze how demographic factors, commute mode selection, vehicle characteristics, and various other factors can explain how individuals expect disruption to their activities. Results suggest that the majority of individuals do not expect major disruptions, although for more car-dependent individuals, disruption was expected to be substantial, especially for work-related trips. These results have implications for the potential success and benefits of an integrated transport policy.     

Technical Note: RMS Values for Control Force, Suspension Stroke and Tyre Deflection in an Active Suspension

Expressions are derived for the numerical computation of rms values for control force, suspension stroke and dynamic tyre deflection in a quarter-car vehicle model on a random road of given roughness. A quadratic performance index is employed and the effects of the assumed weighting factors on the rms values and overall static stiffness determined.     

The competitiveness of short sea shipping in multimodal logistics supply chains: service attributes

Much has been written and spoken about short sea shipping within the European Union (EU) as a means of shifting goods from road to sea and of achieving a sustainable economic development. However, this shift is far from being a general reality, despite the few individual, and success stories that have taken place and the EUROSTAT data suggest that the overall effort has contributed very little towards attaining this desired shift. In the light of this, research was conducted to discover how to put short sea shipping on a more competitive level within European multimodal logistics supply chains. This paper aims at identifying service attributes of short sea shipping operations within multimodal transport chains by means of a questionnaire and, for that, examines the short sea shipping environment and contemporary European logistics trends. The analysis is based on empirical research, involving logistics operators, shippers' associations and intermodal rail operators, and allows an evaluation (based on statistical techniques) of the short sea shipping industry and its competitors. It extends previous work by considering these short sea shipping attributes within a multimodal transport context.