Spark Ignition Engine Idle Speed Control Using a Novel Framework and Enabling Control of the Tradeoff between Fuel Consumption and Load Rejection Capability

In this paper, a new framework for idle speed control is presented [The idle control methodology described paper is protected by international patent law]. A simple new discrete event based engine model evolving in the crank domain is given and is parameterized using a combination of dynamic identification and steady state calibration. The majority of the non-linearities can then be inverted and a second synthetic output is introduced. This second output is the torque reserve of the engine and enables control of the tradeoff between disturbance rejection capabilities and engine efficiency. A linear controller is designed using the H 8 loopshaping technique and results are presented from dynamometer based engine tests.     

在常规线路上实现高速

介绍了在常规线路上实现高速的可行性,阐述了遇到的主要技术难题及解决方法。     

Metropolitan railways: present characteristics and future prospects

Urban bus operation in Chile is totally deregulated. This is the only example in the world where access to the urban bus transport market is totally free, and where the government does not exercise any control over the fares. This policy has been implemented progressively since 1979. Ten years later, it is possible to draw some conclusions from the experience. To summarize these conclusions, one could say that (i) the impact of deregulation has been almost exactly the opposite of what was expected: fares have risen and the diversity of services has been reduced, (ii) the reasons for this discrepancy lie less in the action of a cartel than in the specifics of urban transport supply and (iii) there is probably more to be expected from a refined deregulation policy, taking into account these specifics, than from a drive back to the traditional regulation system.     

Mapping evacuation risk on transportation networks using a spatial optimization model

The focus of this paper is on the development of a methodology to identify network and demographic characteristics on real transportation networks which may lead to significant problems in evacuation during some extreme event, like a wildfire or hazardous material spill. We present an optimization model, called the critical cluster model, that can be used to identify small areas or neighborhoods which have high ratios of population to exit capacity. Although this model in its simplest form is a nonlinear, constrained optimization problem, a special integer-linear programming equivalent can be formulated. Special contiguity constraints are needed to keep identified clusters spatially connected. We present details on how this model can be solved optimally as well as discuss computational experience for several example transportation networks. We describe how this model can be integrated within a GIS system to produce maps of evacuation risk or vulnerability. This model is now being utilized in several research projects, in Europe and the US.     

美国新泽西州马纳霍金海湾大桥的疲劳问题

美国新泽西州72号公路马纳霍金海湾大桥的上部结构由17跨连续及悬臂铆接钢板梁和横梁系统组成,其中包括5跨销钉一吊杆悬挂梁.由于桥梁的"结构性能不足",20世纪90年代初对大桥进行了系统的修复工作.修复实施过程中,在很多部位发现了疲劳裂纹和桥面板混凝土剥落,疲劳裂纹主要为出现在横梁腹板的水平裂纹、横梁与主梁间托板连接角钢...     

铁道车辆液压减振器的工作原理和数值模型

基于液压减振器的工作原理、内部结构和阀元件的性能,建立了一个新的液压减振器数值模型。该数值模型不仅将阻尼力作为减振器活塞杆的速度与位移的函数,同时还含有用于描述内部结构的基本参量,可以清楚地描述液压减振器的阻尼机制。应用该模型可进行液压减振器的动态性能分析、结构设计、元件选用等。模型计算结果与实验数据有较好的符合性。该数值模型易于实现计算机数值仿真,可以应用于车辆系统动力学性能的研究和减振器的结构参数、动态性能对车辆舒适性和稳定性影响的深入分析。     

The potential for British coastal shipping in a multimodal chain

A strategy to revitalize coastal shipping within Great Britain is investigated. An examination of the regulatory environment shows government, at both the EU and British levels, aware of the environmental benefits of coastal shipping compared to road freight transport, if only mildly supportive in tangible terms. The geography of Great Britain and the modern preference for just-in-time deliveries have severely restricted the ability of coastal shipping to compete effectively with road freight transport. The primary objective of the paper is to investigate whether coastal shipping could be integrated into a multimodal door-to-door supply chain, where it is currently hampered by high costs of transhipment, slow transport speeds, and the incongruity of load sizes between land and sea modes. Integration requires the co-operation of all organizations within the multi-modal supply chain. However, coastal shipping companies have been known to be individualistic and mistrusting of alliances. Therefore, a Delphi study is undertaken to investigate the standpoint of leading managers in such companies towards multimodal integration. The results of the Delphi study indicate that managers are in favour of multimodal developments, in particular cooperation between coastal shipping and road haulage. However, there was agreement that the business is highly competitive, and this may prevent the forms of collaboration required for multimodal systems. The secretive nature of the coastal shipping sector could impede joint marketing to promote a mode of transport that is often 'invisible' to shippers. There was little consensus on the relationship that should exist between coastal shipping and ports, a topic worthy of further investigation.     

Problems with certification and legislation

This paper discusses the vast growth of requirements directed toward mobile offshore drilling units attempting to be internationally certified. As a simplistic example, the regulations regarding heliports are examined with the pitfalls and benefits of an international standard discussed from the viewpoint of owner and operator. Recommendations contained in an International Maritime Organization resolution are suggested for use by the various regulatory bodies when dealing with new or amended rules. It is suggested that a more universal standard would evolve if the guidance of the resolution were heeded.     

Aspects of family and kinship in a North Carolina coastal community: a comparative study

The almost total absence of social-science data on North Carolina coastal fishing communities has provoked this preliminary study of the role played by family and kinship ties among fishermen and boat builders in such a community, with a view to developing new fisheries management strategies from an assessment of the social and economic impacts of those which already exist.