舰船信息系统信号接地的电磁兼容性分析

从设备和系统角度对舰船信息系统的接地技术进行详细分析,提出了实用的设计方法和建议,并对数字接地的电磁特性提出了测量建议,给出实用的设计指导原则。     

关联时滞大系统的保性能控制

针对关联项具有N×N个任意未知常时滞的线性连续大系统,采用线性矩阵不等式(LMIs)方法,提出了一种分散的无记忆状态反馈二次保性能控制器的存在条件和设计方法.最后用一个示例说明分散无记忆状态反馈二次保性能控制器的设计方法.     

Alternative fuels for transportation

The alternatives to the oil based fuels for transportation are considered and analysed. These are the synthetic fuels, made from coal, the liquid petroleum gases of propane and butane, compressed natural gas and methanol. The problems associated with the use of electric vehicles are discussed; the main problem being that of range.

The possible use of hydrogen as a fuel is analysed in some detail. Since its supply can be tied directly to nuclear energy sources, rather than hydrocarbon feed stocks, it could be an alternative in the long term. The main problems of the storage of hydrogen on the vehicle and of its propensity to “back‐fire” into the engine intake are discussed. The first can be ameliorated and the second eliminated by dual fuelling; with petrol. It is advocated that the on‐board storage of hydrogen be by the use of hydrides for private cars. However, it is expected that it may be as liquid hydrogen for some forms of transport and will certainly be in this form for aircraft.     

A new composite decision support framework for strategic and sustainable transport appraisals

This paper concerns the development of a new decision support framework for the appraisal of transport infrastructure projects. In such appraisals there will often be a need for including both conventional transport impacts as well as criteria of a more strategic and/or sustainable character. The proposed framework is based on the use of cost-benefit analysis featuring feasibility risk assessment in combination with multi-criteria decision analysis and is supported by the concept of decision conferencing. The framework is applied for a transport related case study dealing with the complex decision problem of determining the most attractive alternative for a new fixed link between Denmark and Sweden – the so-called HH-connection. Applying the framework to the case study made it possible to address the decision problem from an economic, a strategic, and a sustainable point of view simultaneously. The outcome of the case study demonstrates the decision making framework as a valuable decision support system (DSS), and it is concluded that appraisals of transport projects can be effectively supported by the use of the DSS. Finally, perspectives of the future modelling work are given.     

An integrated methodology for the design of mooring systems and risers

Traditionally, the design of mooring lines and risers of floating production systems (FPS) has been performed separately, by different teams, employing uncoupled analysis tools that do not consider the nonlinear interaction between the platform hull and the mooring lines and risers. Design processes have been focused on fulfilling the design criteria of the respective component (mooring/riser) alone, with few or no consideration to the other component, and little interaction between the design teams. Nowadays the importance of employing analysis tools based on coupled formulations is widely recognized, and analysis strategies have been proposed to consider feedback between mooring lines and risers within their respective design processes.In this context, this work details a proposal of one single and fully integrated design methodology for mooring systems and risers for deep-water FPS. In this methodology, the design stages of both risers and mooring lines are incorporated in a single spiral, allowing the full interaction of different teams; mooring design implicitly considers the riser integrity, and vice-versa, leading to gains in efficiency and cost reduction.Different analysis strategies are employed, taking advantage of uncoupled and coupled numerical models. The models generated at the initial/intermediate design stages can be reused in subsequent stages: simpler models are used in the initial stages, and more refined models are gradually introduced, to reach an ideal balance between computational cost and accuracy of results. In the advanced stages, the exchange of information between mooring/riser also allows the definition of criteria for the selection of governing/critical loading cases to be revised and verified in detail. This leads to the reduction of the original loading case matrix, allowing a feasible use of time-consuming fully coupled analysis.Results of a case study illustrating the application of some of the main processes of the methodology are included.     

综合交通信息平台 建设运营机制研究

在分析国内外已建交通信息系统和信息平台建设、运营和服务情况的基础上,研究了信息的平台性质与功能定位、建设运营模式和保障机制。提出了3种适合我国现状的信息平台建设运营模式:政府行为型;政府建设、企业运营型;政府引导、企业运作型。研究了各类模式的特点和适用性。     

基于PDM的汽车并行设计系统研究

分析了传统的汽车产品开发过程中存在的问题，指出基于PDM（产品数据管理）框架的产品并行设计是汽车行业重要选择，在论述了汽车产品并行设计的内涵和PDM的功能的基础上．提出了基于PDM的适合于汽车行业的并行设计体系结构，并对其中的关键技术进行了探讨。     

静液压储能传动汽车动力源系统的匹配效率

为了便于进行汽车动力源系统的参数选择和设计，在试验数据的基础上运用曲面拟合和二维插值的方法，通过模拟计算绘制了液压泵的特性等值曲线；综合发动机和液压泵的特性曲线，分剐对发动机与液压变量泵、定量泵进行了匹配效率分析；考虑蓄能器的效率，建立了发动机与液压泵、蓄能器的效率数学模型以及效率脉谱图，定义了系统效率概念并以此评价动力源系统的经济性，得出了发动机与变量泵、定量泵匹配的效率关系以及动力源系统的最佳工作范围。     

汽车仪表指针控制技术

主要介绍汽车组合仪表指针控制技术，回顾了仪表指针控制技术的发展历程，并对每种控制技术的主要特点进行了详细阐述。     

半主动悬架的滑模变结构控制

针对带有电流变液智能阻尼器的半主动汽车悬架模型,运用滑模变结构方法设计了半主动悬架滑模控制器。根据滑模运动方程稳定的Hurwitz判据选择滑模面系数,用指数趋近率改善滑模运动段的动态品质并进一步确定了半主动悬架的实时控制阻尼力。对多种激励信号下隔振质量的响应及半主动悬架系统在系统参数摄动下的鲁棒特性进行了仿真分析。结果表明:变结构控制下半主动悬架系统的隔振效果要远好于最优被动系统,而且对外界扰动有一定的适应性,对系统参数摄动也具有很强的鲁棒性。