板料成形仿真技术及其工业应用

本文首先回顾了板料成形仿真技术的产生，发展和基本方法，综述了关于该技术的几个基本问题的研究进展和现状。     

Optimising a Car Chassis

This paper presents a method to optimise a car chassis fitted either with passive or active suspensions. Provided that a full vehicle model is available for accurate simulations of many different driving situations (J-turn, lane-change, power-on/power-off on even/rough, dry/wet roads), the method allows to tune the parameters of the chassis system (suspension elastokinematics, stiffnesses, dampings, actuator gains, tyre pressures...) in order to achieve the desired dynamic behaviour of the car in all of the considered driving situations. According with the Global Approximation approach, the original physical car model is substituted by another purely numerical mathematical model (backpropagating Artificial Neural Network). This reduces the simulation time dramatically and enables the optimisation process to come to successful results. The computation of the Pareto-optimal set is performed by using Genetic Algorithms. The method is validated by optimising the parameters of the suspension system of an actual car.     

基于GATS算法的城市土地使用规划问题研究

土地使用规划就是确定和选择可能的发展区域以满足使用土地的要求，包括新区域的形成及提供公共服务设施），最优土地发展规划就是从许多可能的发展区域和人口分配方案中选择最好的方案，这一问题能归结为一个单目标0－1规划问题，本文根据遗传算法和禁忌搜索算法自身的优势与不足，提出一种将二者混合使用求解土地使用规划的算法，以使总的费用最少，同时针对此模型中约束函数的特点，提出一种处理约束的新方法，并用实际问题进行了数值实验，这是第一次将遗传算法和禁忌搜索算法应用于实际的土地使用规划问题。     

A study of the bi-directional pedestrian flow characteristics at Hong Kong signalized crosswalk facilities

This paper investigates the bi-directional flow characteristics at signalized crosswalk facilities in Hong Kong. Pedestrian flow measurements were conducted at selected signalized crosswalks in Hong Kong urban area with and without the Light Rail Transit (LRT) railway tracks in the median of the carriageway. The pedestrian speed-flow functions for these crosswalk facilities were calibrated. The relationships between the walking speed at capacity and directional distribution of pedestrian flow (or flow ratio) are determined. The effects of different flow ratio on the effective capacity are also investigated. The bi-directional pedestrian flow effects on signalized crosswalk facilities with LRT tracks are found more significant than those without LRT tracks. The result could be used as a basis to improve the assessment of the crosswalk's capacity and to determine the design walking speeds under different flow ratios at signalized crosswalks in Hong Kong and in other Asian cities with similar environments.     

Achievable Dynamic Response for Automotive Active Suspensions *

A complete set of constraints is derived for the road disturbance transfer functions in a quarter car model of an automotive active suspension, for typical choices of measured outputs. It is shown that any road disturbance responses which are achievable using “full state feedback” can be achieved, to within an arbitrary small tolerance, using a dynamic compensator measuring suspension deflection only. Also considered are the disturbance responses to loads acting on the sprung mass, and a complete set of constraints is derived for these. It is shown that road disturbance and load disturbance responses can be determined independently if suspension deflection and sprung mass velocity are measured. Indeed, any responses achievable separately with “full measurements” can be approximated together to an arbitrary small tolerance. Certain integral relationships are shown to follow from the derived transfer function constraints. These relationships imply fundamental limitations for certain responses (e.g. tyre deflection) no matter what measurements are available for feedback.     

氢在高强度管道钢应力腐蚀中的作用

用显微镜观察了不同充氢电流下X80管道钢恒载荷拉伸试样的显微组织和断口形貌 ,测定了管道钢中氢致附加应力。结果表明 :随氢浓度增加、应力减小 ,试样断口逐渐从韧性断口向脆性断口过渡 ;断裂微裂纹通常在点蚀坑和杂质处形成并呈不连续扩展 ,形成穿晶断裂 ;管道钢中氢致附加应力随氢浓度的增加而线性升高     

Short-line railroad managers discuss their industry

In the United States, the 1980 Staggers Rail Act created a positive regulatory environment for the creation of new short-line railroads. At present there are about 450 of these railroads that have less than 250 miles of trackage. This study asked managers/owners of these railroads two basic questions. First, what do you believe is the single most important trend that is currently taking place in your industry. The most frequently noted trend was the frustration of working with the larger Class 1 railroads. Five additional trends were also identified by the respondents. The second question asked the respondents if they thought the short-line sector of the rail industry will become more or less important in the next ten years and why. About 70% of the owner/managers believed their industry would become more important in the next decade. The most commonly expressed reason for this position is that the Class 1 railroads will increasingly specialize in mainline service only. Three other rationales were also enumerated. For the managers that thought their industry would become less important, the most noted reason was their trackage would not safely transport the newer very heavy bulk commodity freight cars.     

汽车网络技术

综述了当前汽车网络技术应用和发展；简要介绍了一些新型汽车网络和线控技术；对汽车网络技术的发展进行了讨论。     

提高圆柱齿轮滚、剃加工质量和效率的途径

通过对齿轮加工理论及试验数据的分析，提出了提高齿坯精度、滚齿精度、剃齿精度及齿轮生产效率的方法；详细介绍了提高滚齿精度的措施及调整方式、滚齿齿形的保证方法、影响齿向误差的因素等；还介绍了影响剃齿精度的因素及保证措施，以及冷加工应力对零件热变形的影响及保证措施；同时介绍了一些齿轮加工的技巧和生产现场经验。     

IMAGE SEGMENTATION BASED ON MARKOV RANDOM FIELD AND WATERSHED TECHNIQUES

IntroductionThere are many methods to perform imagesegmentation and edge detection tasks that incor-porate region- growing and edge detection tech-niques,for example,it is applying edge detectiontechniques to obtain Difference In Strength( DIS)map then employ region growing techniques towork on the map as in Refs.[1 ,2 ]. In the others,combining both special and intensity information inimage segmentation approach based on multi- reso-lution edge detection,region selection and intensi-ty thre…