Environmental impacts of transformative land use and transport developments in the Greater Beijing Region: Insights from a new dynamic spatial equilibrium model

This paper reports the insights into environmental impacts of the ongoing transformative land use and transport developments in Greater Beijing, from a new suite of dynamic land use, spatial equilibrium and strategic transport models that is calibrated for medium to long term land use and transport predictions. The model tests are focused on urban passenger travel demand and associated emissions within the municipality of Beijing, accounting for Beijing’s land use and transport interactions with Tianjin, Hebei and beyond. The findings suggests that background trends of urbanization, economic growth and income rises will continue to be very powerful drivers for urban passenger travel demand across all main modes of transport beyond 2030. In order to achieve the dual policy aims for a moderately affluent and equitable nation and reducing the absolute levels of urban transport emissions by 2030, road charging and careful micro-level coordination between land use, built form and public transport provision may need to be considered together for policy implementation in the near future.     

A bi-objective bi-level signal control policy for transport of hazardous materials in urban road networks

A bi-objective bi-level signal control optimization for hazardous material (hazmat) transport is considered to assess trade-offs between travel cost and environment impacts such as public risk exposure. A least maxi-sum risk model with explicit signal delay is presented to determine generalized travel cost for hazmat carriers. Since the bi-level signal control problem is generally a non-convex program, a bundle method using generalized gradients is proposed. A bounding strategy is developed to stabilize solutions of the bi-level program and reduce relative gaps between iterations. Numerical comparisons are made with other risk-averse models. The results indicate that the proposed bi-objective bi-level model becomes even amiable to signal control policy makers since provides flexible solutions whilst is acceptable to carriers since takes account of travel delay at signal-controlled junctions. Moreover, the trade-offs between public risk and generalized travel costs are empirically investigated among different risk models with a variety of weights. As a result, the proposed model consistently exhibits highly considerable advantage on mitigation of public risk whilst incurred less cost loss as compared to other alternatives.     

Finding a balance: companies,seafarers and family life

Separation from partner and family has been found to be one of the most significant causes of stress for seafarers, with separation from the family one of the most important ‘stress’ factors influencing a decision to reduce planned sea service. Drawing on in-depth interviews with seafarers' partners in the UK, China and India, this paper focuses on the impact of seafaring on family life, with particular attention given to the effects of differing conditions of service and the range of company support available to seafarers and their partners. The paper concludes that the negative consequences of seafaring can be minimized by such policies as shorter trips, continuous employment (rather than employment by voyage) and opportunities for partners and families to sail. Whilst these measures may have financial costs, these can be off-set by improved retention of seafarers and the avoidance of stress-related illnesses. Indeed, at a time when there is a projected shortfall of well-trained seafarers, such steps may be sound company policy     

A decision support approach to the computerisation of some operational decision problems in community transport

Community Transport (CT) in the UK operates a diverse range of services, and organisations are computerising management and operational functions. This paper describes the approach which has been taken to computerising four operational decision making functions.

The paper considers models of human decision making and problem solving, with particular reference to an information processing view of cognitive activity and to perception and memory. The design of decision support systems is also discussed.

Four decision problems are considered. For each, the paper considers how people tackle the problem, how computers can be used to tackle it and the approach which has been adopted.

For allocating trips to vehicles using a diary, the approach has been to provide a representation on screen of a manual diary. For vehicle brokerage, vehicles are presented to the operator allocating a booking in an order based on the Sequence Number, an index of how ‘difficult to book’ a vehicle is, and the distance of the vehicle's base from the start point of the trip. For the sorting of passenger pick‐ups into an efficient tour, traditional solutions to the travelling salesperson problem have been rejected in favour of a solution using spacefilling curves. Finally, for allocating dial‐a‐ride passenger trips to vehicle shifts an approach has been chosen which presents the operator with appropriate information rather than attempting to automate the scheduling.

The paper concludes that the approach to the diary has been successful and accepted by operators, although the similar approach to the dial‐a‐ride scheduling has not, as the system has not yet been able to replace manual scheduling aids. The facility to order passenger pick‐ups is little used by operators. Finally, it is suggested that the vehicle brokerage problem may be an appropriate use of fuzzy logic.     

城市轨道交通行车配线冗余设计研究

结合配线设置原则与依据、典型城市已运营线路配线布置和故障情况,从辅助配线布置形式、救援方式等角度分析配线设置与故障发生的关系并反思配线设计的不足,提出后续线路配线设计中应坚持运营功能为主的原则,并给出提高配线冗余设计的相关建议。     

Route structures in air transportation—the situation in the federal republic of Germany

This paper deals with route structures in air transportation in general and describes the derivation of such structures. Based on an extensive analysis of scheduled air traffic in Germany, an overview of the situation in domestic and international air travel is given. In particular, relationships were found which permit—in connection with a number of influencing factors—to derive from the present situation route structures, which are also valid for a future year.

This approach was used for the assignment of origin‐destination‐passenger flows to air network routes in a forecast of demand and services in commercial air transportation of the Federal Republic of Germany for the year 1995.     

Patterns of motorization development and next-generation mobility systems

This paper discusses the appropriateness of the “3-stage urban transport policy development cycle” hypothesis proposed by Professor Peter Jones and the importance of both local development context and motorization transport culture in transport policy. It then makes some observations on the future prospects for sustainable cities and transport through major technological innovations in connected and autonomous vehicles, that is, in “Auto Sapiens” as next generation vehicles.     

基于属性数学的铁路重载运输安全评价

铁路重载运输设施设备要求高,确保其安全运行意义重大。属性数学理论主要研究和解决定性描述的度量和不同的定性描述之间的关系问题,基于此,从人员、设备、环境及管理4个方面建立包含3层级28项指标的铁路重载运输安全综合评价指标体系;采用德尔菲法和模糊统计法得到指标初始权值,并通过灰色关联法判断指标权值的合理性。建立铁路重载运输安全综合评价模型,重点利用属性集和属性测度理论研究并制定单指标等级划分标准,采取正规模糊子集以及置信度准则等方法构造属性测度函数以及属性识别准则。以呼和浩特铁路局大包线重载运输为例,应用所建模型评价其安全等级,评价结果符合呼和浩特铁路局实际情况,表明所建模型能较好适用于铁路重载运输安全综合评价。     

《铁路信号显示的发展与思考》之二——多种显示制式的混用

由于混运、兼运的需求,再加故障备用模式,导致在同一线路上显示制式常常混用,情况复杂。不同的显示制式有不同显示方式,原则和规定,与行车有关的人员应当熟悉。     

Identifying multiclass vehicles using global positioning system data

It has been previously evidenced that global positioning system (GPS) data can be used to distinguish passenger cars from delivery trucks. In this paper, a machine learning approach is proposed to use GPS data to identify multiclass vehicles, including passenger cars, single unit trucks, and multi-trailer trucks. The method is acceleration and deceleration-based since it considers the variations of acceleration and deceleration as the most effective features to classify vehicles. The overall classification result for the three vehicle classes is about 75%. The major challenge is to distinguish single unit trucks from multitrailer trucks due to their somewhat similar mobility patterns. The paper also explores the impacts of GPS sampling frequency on vehicle classification. It is found that the proposed multiclass vehicle classification can be reasonably conducted if the data are collected frequently enough (i.e., every five seconds or more frequently) to capture the major acceleration and deceleration processes. The proposed method can be considered as a low-cost and non-intrusive approach to collect vehicle class information and to potentially supplement the existing classification schemes in urban areas.