Department for Transport

Vendor Managed Inventory (VMI) involves the vendor making the replenishment decision for products supplied to a customer based on various inventory and supply chain policies. Information sharing between supply chain members is required in VMI. Sometimes VMI decisions are delayed and/or the information shared is inaccurate. This research examines the effects of information delay and accuracy, and the sharing of sales and forecast information in a VMI environment facing stationary and nonstationary demand. The simulation experiments show the impact of information delay, information inaccuracy, and information sharing on a variety of performance measures, including inventory levels and fill rates.

We assess the strengths and weaknesses of strategies for creating nanoporous hydrogen storage sorbents.

In this paper, we represent a systematic review of stated preference studies examining the extent to which cycle infrastructure preferences vary by gender and by age. A search of online, English-language academic and policy literature was followed by a three-stage screening process to identify relevant studies. We found 54 studies that investigated whether preferences for cycle infrastructure varied by gender and/or by age. Forty-four of these studies considered the extent of separation from motor traffic. The remainder of the studies covered diverse topics, including preferred winter maintenance methods and attitudes to cycle track lighting. We found that women reported stronger preferences than men for greater separation from motor traffic. There was weaker evidence of stronger preferences among older people. Differences in preferences were quantitative rather than qualitative; that is, preferences for separated infrastructure were stronger in some groups than in others, but no group preferred integration with motor traffic. Thus, in low-cycling countries seeking to increase cycling, this evidence suggests focusing on the stronger preferences of under-represented groups as a necessary element of universal design for cycling.

In recent years, there has been a growing interest in a range of transport policy initiatives which are designed to influence people's travel behaviour away from single-occupancy car use and towards more benign and efficient options, through a combination of marketing, information, incentives and tailored new services. In transport policy discussions, these are now widely described as 'soft' factor interventions or 'smarter choice' measures or 'mobility management' tools. In 2004, the UK Department for Transport commissioned a major study to examine whether large-scale programmes of these measures could potentially deliver substantial cuts in car use. The purpose of this article is to clarify the approach taken in the study, the types of evidence reviewed and the overall conclusions reached. In summary, the results suggested that, within approximately ten years, smarter choice measures have the potential to reduce national traffic levels by about 11%, with reductions of up to 21% of peak period urban traffic. Moreover, they represent relatively good value for money, with schemes potentially generating benefit:cost ratios which are in excess of 10:1. The central conclusion of the study was that such measures could play a very significant role in addressing traffic, given the right support and policy context.

This editorial overview of the Special Issue on 'Peak Car' previews the seven papers, drawing out common themes and differences. It starts with a brief overview of the emergence and characteristics of the 'peak car' idea, including recent research and discussions. It draws out the key themes from each of the seven papers in turn and discusses implications for research and policy. It concludes that there is now little doubt that young peoples' car use has reduced, but there is still doubt about how younger people will travel as they age, or how the next generation will travel; that location and settlement density effects are very important, meaning that future population distributions will be significant; and that while 'economic' factors are still seen to be important, elasticities with respect to price and income are falling, with signs of differential responses by population categories and location. In policy terms, it concludes that with the current level of uncertainty about future car use levels, rather than developing policy based on one forecast, we should be developing policy for a range of plausible scenarios.

The objective of this paper is to analyse the factors determining household car travel,
\nand specifically the effects of household income and the prices of cars and motor fuels, and
\nto explore the intertemporal pattern of adjustment. The question of asymmetry in the
\nresponse to rising and falling income is also addressed. Such asymmetry may be caused by
\nhabit or resistance to change or the tendency to acquire habits to consume more easily than
\nto abandon them. The impact of prices, the speed of adjustment and the resistance to
\nchange will be important in determining the possibility of influencing travel behaviour and
\nspecifically car use. The study utilises repeated cross-section data from the annual UK
\nFamily Expenditure Surveys and employs a pseudo-panel methodology. The results are
\ncompared with those for car ownership estimated on the basis of similar models.

Abstract The congestion charging schemes in London and Singapore are compared and assessed in the light of guidelines set out in the Smeed Report, published by the UK Ministry of Transport in 1964 Ministry of Transport. 1964. Road Pricing: The Economic and Technical Possibilities, London: HMSO. [Google Scholar], and their performance in reducing congestion and raising net revenue. The aim is to draw lessons for other towns and cities considering the introduction of congestion charging. One important result from Electronic Road Pricing in Singapore is that a per‐entry charge is more effective at reducing congestion than a per‐day charge. It is concluded that although Electronic Road Pricing in Singapore is more in line with the desirable properties outlined in the Smeed Report, both schemes are part of a wider package of transport policies, and that is probably the most important reason for their success. The main lesson for other towns and cities around the world considering the possibility of introducing congestion charging is that any such scheme ought to be accompanied by complementary measures that will provide motorists with a valid alternative to the car.

Optimal control of enclosed environment requires detailed information of air distribution that could be obtained by numerically solving Navier-Stokes equations with a suitable turbulence model. This investigation evaluated the performance of eight turbulence models for transient airflow in an enclosed environment using experimental data obtained in a room. The study used the room to create three cases with gradually added flow features, which were jet, separations, and thermal plumes. The flow regimes were transitional. The study found that some Reynolds Averaged Navier-Stokes (RANS) models were good for simple but not complicated flows. The large-eddy-simulation (LES) model was the most accurate and stable. The detached-eddy-simulation model (DES) model underpredicted turbulence kinetic energy near the walls. If the DES model include the subgrid-scale turbulence kinetic energy, the results can be significantly improved. This study shows the advanced features of LES and DES models for solving airflow in enclosed environment.

In October 2010, parties to the Convention on Biological Diversity adopted the Nagoya Protocol on Access to Genetic Resources and the Fair and Equitable Sharing of Benefits Arising from their Utilization. One impetus behind the Nagoya Protocol was the mandate to address the unjust impacts—such as the loss of access to resources, exploitation of traditional knowledge, and expropriation of rights to resources—of the global demand for genetic resources on indigenous peoples and local communities (ILCs). Using collaborative event ethnography, this article demonstrates the limited nature, scope, and engagement of the ILC justice discourse in the negotiations, despite the supposedly inclusive nature of the CBD. I attribute the constrained discourse in part to the existence of a justice metanorm as evidenced through the emergence of shared meanings and prescriptive status of justice instruments.

ISSN:1556-8318

Throughout its history, Operational Research has evolved to include methods, models and algorithms that have been applied to a wide range of contexts. This encyclopedic article consists of two main sections: methods and applications. The first summarises the up-to-date knowledge and provides an overview of the state-of-the-art methods and key developments in the various subdomains of the field. The second offers a wide-ranging list of areas where Operational Research has been applied. The article is meant to be read in a nonlinear fashion and used as a point of reference by a diverse pool of readers: academics, researchers, students, and practitioners. The entries within the methods and applications sections are presented in alphabetical order. The authors dedicate this paper to the 2023 Turkey/Syria earthquake victims. We sincerely hope that advances in OR will play a role towards minimising the pain and suffering caused by this and future catastrophes.

A unified methodology has been proposed for the quantification of congestion, incorporating the volume and operational characteristics of traffic movement. The level of congestion has been modeled to relate to the causal influences of traffic movement. Modeling congestion has provided a quantitative basis for understanding the contribution of different vehicle types in overall congestion, and it is useful for evolving the policy for congestion mitigation. Quantified congestion level has been used as a logical and improved measure of effectiveness to account for the conceptual definition of level of service in a quantitative manner. Based on the congestion level, 10 levels of service have been proposed, with 9 in a stable flow zone (presently designated as A–E), and 1 representing an unstable operation (presently designated as F). The philosophy has been demonstrated by developing congestion models and assessing the effect of roadway width on congestion levels and service volumes. While it is possible to assess the realized benefits from an increase in roadway width, the required number of traffic lanes for a desired level of service can also be estimated.

Motorcycles constitute a significant proportion of traffic in many countries but are poorly represented in existing traffic flow theories and simulation software. A new approach to modeling mixed traffic is introduced focusing on depicting the movements of motorcycles. In this study, the characteristic patterns of motorcycle behavior were identified, and the key elements contributing to these patterns were extracted. Then three mathematical models were developed to depict these key elements, which were calibrated by using field data collected at Victoria Embankment in central London. After the calibration procedures, these models were integrated into an agent-based simulation model system. The ability of the simulator to reproduce plausible patterns of car and motorcycle behavior was verified. A number of potential applications of this simulator for the management of mixed traffic streams in urban areas are discussed.

This paper discusses the nature and consequences of uncertainty in transport systems. Drawing on work from a number of fields, it addresses travellers’ abilities to predict variable phenomena, their perception of uncertainty, their attitude to risk and the various strategies they might adopt in response to uncertainty. It is argued that despite the increased interest in the representation of uncertainty in transport systems, most models treat uncertainty as a purely statistical issue and ignore the psychological aspects of response to uncertainty. The principle theories and models currently used to predict travellers’ response to uncertainty are presented and number of alternative modelling approaches are outlined. It is argued that the current generation of predictive models do not provide an adequate basis for forecasting response to changes in the degree of uncertainty or for predicting the likely effect of providing additional information. A number of alternative modelling approaches are identified to deal with travellers’ acquisition of information, the definition of their choice set and their choice between the available options. The use of heuristic approaches is recommended as an alternative to more conventional probabilistic methods.

BACKGROUND: Walking school buses (WSBs) offer a potentially healthier way for children to get to school while reducing traffic congestion. A number of pressing societal challenges make it timely to evaluate evidence of their value. METHODS: Studies that focused solely on WSBs were identified through online and manual literature searches. Twelve WSB studies involving a total of 9169 children were reviewed. Study aims, designs, methods, outcomes, and barriers and facilitators were examined. RESULTS: WSBs were found to be associated with increased prevalence of walking to school and general activity levels although not always significantly. Time constraints emerged as barriers to WSBs, impacting on recruitment of volunteers and children to the WSBs. Facilitators of WSBs included children enjoying socializing and interacting with the environment. CONCLUSIONS: Preliminary evidence of the health value of WSBs was demonstrated, along with recommendations for the design of future studies. By tackling barriers of time constraints, volunteer recruitment, and parents' safety concerns while at the same time, increasing convenience and time savings for families, future WSBs are likely to be more sustainable and taken up by more schools. Implications for future innovation in school health were identified.

Abstract Two case studies are presented as examples of a decision‐analysis approach to engineering design for projects in which the hydrogeological environment plays an important role. This approach to design involves quantifying benefits, costs, and risks for each design alternative under consideration. Risk, which is defined as the expected costs of failure, reflects both performance uncertainties and failure costs. Probabilities of failure are estimated by coupling stochastic ground‐water flow and solute transport models with uncertainty models that represent input parameters as random variables. The case studies that are used to describe the approach involve (1) selecting a pumping rate for an extraction well to capture an existing contaminant plume, and (2) designing a leachate collection system for a soil remediation facility. The examples illustrate that the decision‐analysis approach can be accomplished using relatively simple analytical models to simulate the behaviors of hydrogeological environments and engineering components. The results identify how the preferred design alternative depends upon the regulatory, hydrogeological, and economic environments in which the decision is made. For the extraction well example, the preferred alternative is relatively insensitive to the costs of failure but is dependent upon the expected dimensions of the contaminant plume. For the soil remediation example, the preferred design alternative depends upon the anticipated costs of failure and the regulatory standard for ground‐water contamination. Reducing the variance or uncertainty in dispersivity values by a factor of 3 had a relatively small effect on the overall design of the leachate collection system.

Thirteen male instructors were monitored during a total of 44 live fire training exercises (ambient temperature 74+/-42 degrees C). Exposure time during the 'Hot Fire' (HF), 'Fire Behaviour' and 'Fire Attack' exercises was 33.0+/-7.9 min (n=30); 26.3+/-5.5 min (n=6); and 7.3+/-2.6 min (n=8) respectively. At the end of the exercises, mean core temperature (t(core)) was 38.5+/-0.9 degrees C (n=32), however eight instructors had a t(core) above 39 degrees C. The mean maximum temperature under the fire hood was 41.2+/-4.6 degrees C (n=40). Mean maximum heart rate (HR) was 138+/-26 bpm (n=34) however, in five exercises, HR exceeded 90% of the instructors' HR reserve. Mean fluid deficit was 0.62+/-0.6 l (n=30) at the end of the HF exercises, the maximum being 2.54 l. Four instructors doubted their ability to perform a rescue at the end of the exercise. The energy cost of performing simulated rescues of a 50 kg dummy in the cool was investigated in a pilot study. Mean HR during the rescues was 79+/-7% of the instructors' HR reserve and it was estimated that this could increase t(core) by 0.4 to 0.6 degrees C. The physiological responses to the fire-fighting exercises varied considerably and reflected the differences in work performed and external heat load. The results obtained from some individuals give cause for concern, and signs of heat strain were seen in at least two individuals.

This paper examines the development, use, and evaluation of a new traffic conflict analysis technique that specifically addresses pedestrian–vehicle conflicts with the intention of being applicable to shared-space environments. The method is based on an existing, well-established, and widely used vehicle–vehicle conflict analysis technique, but is adapted to consider the movement of pedestrians, which differs significantly from that of vehicles. The new method is then implemented on the Exhibition Road site of West London with the use of video data collected from locations with a potentially high concentration of vehicle–pedestrian conflicts, and the results of the analysis are presented. Finally, the results are compared with those obtained by other conflict analysis techniques and also against accident data to assess not only the accuracy but also the functionality of the new technique.

This paper describes the design of an evaluation methodology—the Plan-Process-Results (PPR) approach—and its application to the municipal urban plans currently in force in the two largest Portuguese cities, Lisbon and Oporto. After the identification of the main contributions from a literature review, the fundamental elements of this methodology are characterised. Each case study is appraised according to rationality, performance and conformance, and a number of planning proposals are presented to improve planning practice in each of these cities. Finally, the main similarities and differences between both case studies, as well as the main reasons for these, are identified.

Changes in pedestrian–vehicle traffic conflicts in urban streets redesigned according to the principles of shared space were investigated with a recently developed pedestrian–vehicle conflict analysis (PVCA) method. In a first step, the PVCA method was revised to reflect more accurately the features of shared space; this revision included the definition of a systematic process for identifying conflict occurrences on the one hand and the full quantification of the conflict severity grading process on the other. Then the refined PVCA method was applied to a case study in London with video data from periods before and after the redevelopment of the Exhibition Road site from a conventional dual carriageway to a modern design with some elements of shared space. The results of the comparative analysis indicated a general decrease in traffic conflict rates as a result of the redesign but also highlighted specific issues that may require additional analysis.