钻孔废弃泥浆处理管理要求综述

对钻孔废弃泥浆诱发的环境问题进行了分析调查,对国内外废弃泥浆的管理要求进行了调研,分析了废弃泥浆污染事故时有发生的原因,提出应在建设项目环境影响评价中明确废弃泥浆的处理措施、开发废弃泥浆的现场处理技术、政府相关部门应加强对工程施工的监管力度。     

新版国家标准《地铁设计规范》修订辑要与浅识

针对国家标准《地铁设计规范》的修订工作,对其中重要及影响面较大的修订和补充规定,以及一些有争议的技术要求进行介绍和分析,如调整设计年限执行的严格程度、增订车体与站台门之间的间隙规定、放宽线路最大坡度的规定、修订自动扶梯角度与配置量、地下结构放宽最大计算裂缝宽度允许值、增订站台处走行轨对地电压的规定、取消环保防护按距离要求的规定等。阐明关于车厢有效空余地板面积站立乘客密度、设置区间应急疏散平台等有争议的规定的处理方法,供有关专业人员参考使用。     

基于运营场景的CTCS-3级列控系统功能需求分析

为了满足我国高速铁路的运营要求,通过自主创新形成了一套完整的基于无线闭塞技术的中国列车运行控制系统CTCS-3级规范。从CTCS-3级列控系统运营场景的角度,对CTCS-3级列控系统的功能需求进行分析,包括列车注册与注销、等级转换、行车许可、调车、紧急情况处理、临时限速、RBC切换等。     

System convergence — The potential for an integrated road transport environment

This chapter discusses the potential for co-ordinating developments in Road Transport Informatics (RTI) in what could otherwise be a number of fragmented approaches, in order to approach what the DRIVE programme calls the Integrated Road Transport Environment (IRTE). The discussion is presented with particular reference to European developments such as the PROMETHEUS and DRIVE research programmes, but is intended to encompass possible progress towards worldwide standardisation.The role of consensus formation in Europe in the DRIVE projects SECFO and TARDIS is described. The importance of dynamic route guidance and of automatic debiting systems are highlighted in identifying the likely impetus towards the implementation of RTI systems. Finally, some outstanding issues are presented briefly, and the possible emergence of international standards leading to compatible systems worldwide is discussed.     

铁路平车贯彻国防要求研究

分析了我国铁路平车贯彻国防要求的现状及存在问题,论述了铁路平车贯彻国防要求的意义与依据,探讨了具体的方法措施,对铁路平车贯彻国防要求具有一定的参考价值。     

Optimal combinations of selected tactics for public-transport transfer synchronization

Handling efficiently and effectively real-time vehicle control is of major concern of public transport (PT) operators. One related problem is on how to reduce the uncertainty of simultaneous arrivals of two or more vehicles at a transfer point. Improper or lack of certain control actions leads to have missed transfers, one of the undesirable features of the PT service. Missed transfers result in increase of passenger waiting and travel times, and of passenger frustration. This work focuses on reducing the uncertainty of missed transfers by the use of control tactics in real-time operation. The developed model improves the PT service performance by optimally increasing the number of direct transfers and reducing the total passenger travel time. This model consists of two policies built upon a combination of two tactics: holding and skip-stop/segment, where a segment is a group of stops. The implementation of the concept is performed in two steps: optimization and simulation. The optimization searches for the best combination of operational tactics. The simulation serves as a validation of the optimal results under a stochastic framework. A case in Auckland, New Zealand is used. The results show that by applying the holding-skip stop, and holding-skip segment tactics the number of direct transfers are increased by about 100% and 150%, and the total passenger travel time is reduced by 2.14% and 4.1%, respectively, compared with the no-tactic scenario. The holding-skip segment tactic results with 47% more direct transfers than the holding-skip stop tactic for short headway operation.     

Strain estimation for offshore wind turbines with jacket substructures using dual-band modal expansion

Structural fatigue is a design driver for offshore wind turbines (OWT). In particular, the substructures, like jackets, are strongly affected by fatigue. Monitoring the fatigue progression in the welds is vital for the maintenance and a potential lifetime extension. However, inspections of critical locations are costly due to the limited accessibility of the mostly submerged jacket. Considering the high number of potentially critical welds, it is regarded as economically unfeasible to equip all fatigue hot spots with sensors. Thus, an indirect method to monitor the fatigue progress of the structure and point out critical locations is desirable. For a consistent support of ongoing maintenance, it has to yield reliable results for varying operational and environmental conditions. This paper applies a virtual sensing approach to jacket substructures. From a small set of sensors on the tower, fatigue at every desired location of the jacket is estimated using dual-band modal expansion. Simulations using the OC4 jacket design are performed to show potentials and limitations of the method. Namely fatigue progress on leg welds of K-joints is predicted with high accuracy over a wide range of load cases. However, some difficulties in fatigue prediction of X-joints due to the occurrence of local modes and limitations in the extrapolation of wave loading have to be resolved in future work.     

电动助力转向器的设计要求

为了促进国家标准或行业标准的旱日制定，文章提出了电动助力转向器的一些设计方面的要求。介绍了电动助力转向器的结构，阐述了其基本性能、工作环境及安全性要求，表明电动助力转向器具有结构简单、动力消耗小和节约能源等显著优势。指出目前国内许多自主品牌轿车都已安装了自己研发的电动助力转向器，其蓬勃的发展势头必将使电动助力转向器取代液力助力转向器成为可能。     

绿色交通概念解析

分析了交通系统对资源环境的影响机理,在考察"可持续发展"、"低碳"、"节能减排"、"循环"等相关概念的基础上,提出绿色交通的内涵,并对其发展要求和具体理念进行了分析。     

Probabilistic assessment of aviation CO2 emission targets

Passenger demand for air transportation is expected to continue growing into the future. The increase in operations will undoubtedly lead to an escalation in harmful carbon dioxide emissions, an adverse effect that governing bodies have been striving to mitigate. The International Air Transport Association has set aggressive environmental targets for the global aviation industry. This paper investigates the achievability of those targets in the US using a top-down partial equilibrium model of the aviation system complemented with a previously developed fleet turnover procedure. Three ‘enablers’ are considered: aircraft technologies, operational improvements and sustainable biofuels. To account for sources of uncertainty, Monte Carlo simulations are conducted to run a multitude of scenarios. It was found that the likelihood of meeting all targets is extremely low (0.3%) for the expected demand growth rates in the US. Results show that biofuels have the most impact on system CO₂ emissions, responsible for an average 64% of the total savings by 2050 (with aircraft technologies and operational improvements responsible for 31% and 5%, respectively). However, this impact is associated with high uncertainty and very dependent on both biofuel type and availability.