37CrNi3钢过热后冷却方式对断口遗传的影响

本文结合金相组织,宏观断口和微观断口对37CrNi3钢经1300℃过热,并以不同方式冷却后,再经正常淬火消除过热粗大组织后出现的断口遗传现象进行了研究.结果表明,经过热后淬火,冷待淬火及空冷预处理所出现的断口遗传均属石状断口,其中经过热后直接淬火试样,断口遗传面积最小.     

Benzene concentrations on board chemical tankers

Maritime transport of benzene is regulated by the International Maritime Organisation (IMO). Two important guidelines for a ship’s crew in this matter are IMO circulars 1095 and 1220. The first one describes the minimum safety standards for ships carrying liquids in bulk containing benzene while circular 1220 deals with structural guidelines for new ships carrying liquids in bulk containing benzene, but also technical developments could help in improving safety and health protection on board chemical tankers carrying benzene in bulk. The aim of the present paper is to determine the benzene concentration in the working and living environment on board a modern chemical tanker carrying benzene in bulk, where all safety, technical and operational procedures described by IMO in the above-mentioned circulars are followed. During specific cargo operations, we measured the benzene concentrations on different locations on board by means of Radiello® passive diffusive samplers. Despite all measures taken, we found an important difference in benzene concentration between operations with a benzene cargo compared to operations without benzene on board, as well as inside and outside the accommodation. Moreover, even during discharge operations, where the emission is theoretically zero, we found an important increase in the benzene concentration. In addition, we found less favourable results for the engine room.     

集成化核动力装置运行支持系统设计分析

为防止和减少核动力装置运行人员的操作失误,采用将运行支持技术与运行人员认知过程相结合的方法,对运行支持系统进行设计分析,提出一个集成化核动力装置运行支持系统的体系结构,为开发实际系统提供参考.     

Numerical simulation of nonlinear wave force on a quasi-ellipse caisson

A three dimensional numerical model of nonlinear wave action on a quasi-ellipse caisson in a time domain was developed in this paper. Navier-Stokes equations were solved by the finite difference method, and the volume of fluid (VOF) method was employed to trace the free surface. The partial cell method was used to deal with the irregular boundary typical of this type of problem during first-time wave interaction with the structure, and a satisfactory result was obtained. The numerical model was verified and used to investigate the effects of the relative wave height H/d, relative caisson width kD, and relative length-width ratio B/D on the wave forces of the quasi-ellipse caisson. It was shown that the relative wave height H/d has a significant effect on the wave forces of the caisson. Compared with the non-dimensional inline wave force, the relative length-width ratio B/D was shown to have significant influence on the non-dimensional transverse wave force.     

Biomechanical properties and modeling of skin with laser influence

This paper studied experimentally and theoretically the biomechanical properties of skin with laser influence. Different types of tensile tests of the porcine skin in vitro were conducted to study effect of the laser, tensile strength, stress-strain relationship, influence of skin’s anisotropy and different regions, repetitive loading and stress-relaxation. A modeling of skin was developed according to the experimental results. The modeling provided insights into the important structure-function relationship in skin tissue with the laser effect. The nonlinear and anisotropic mechanical responses of skin are largely due to varying degree of fiber undulation which is effected by laser and outside forces. By introducing the laser factor into the constitutive modeling, the skin’s biomechanical properties and the mechanism of the skin repair with laser were discussed.     

蜗杆凸轮间歇运动机构参数化设计与动力学仿真

采用基于特征模型的造型方法,利用CATIA中CAA二次开发功能实现了蜗杆凸轮的参数化建模.然后在ADAMS中对蜗杆凸轮间歇运动机构进行动力学仿真,分析了啮合过程中输出轴角速度、角加速度及啮合力的变化特性.     

根式仿生基础应用技术研究

根式基础作为一种仿生结构,近年来在我国开展了一定的研究,并在部分工程中得到了成功的应用.该文结合相关理论分析、工艺试验、施工实践和应用实例,分析根式基础的应用技术,为该新型技术的推广应用提供参考.     

人机工程在驾驶员坐姿优化中的应用-朗逸转向柱人机优化

分析了中德人体尺寸的差异性.基于人体尺寸差异会导致驾驶坐姿发生变化,为此提出中国人体的驾驶员座椅调节范围相对欧洲人体可以适当缩小建议,为朗逸转向管柱由德国大众PQ34平台上采用的四向调节改为只有高度调节提供了必要的理论依据.对于只有高度调节的转向管柱,分析校核了转向盘/仪表盘视野和驾驶坐姿舒适度,设计结果为中国用户接受.     

单电机强混合动力电动车辆的动态协调控制

为减小或消除单电机式强混合动力电动车辆在纯电动模式与发动机驱动模式间切换时产生的动力系统冲击,提出了发动机起动过程的转矩协调控制策略和发动机退出过程的转矩补偿控制策略.转矩协调控制策略包括起动模式下的发动机起动阻力转矩补偿控制和调节模式下的发动机过冲转矩平衡控制,转矩补偿控制策略利用电机补偿发动机退出过程中动力系统转矩的变化.台架和实车试验结果表明了该动态协调控制策略可确保发动机的快速平稳起动和发动机退出时不产生动力系统冲击.     

汽车喇叭机-电-磁-声耦合场仿真方法的研究

建立了汽车喇叭的机-电-磁-声多场耦合模型,结合ANSYS、ADAMS和FLUX等有限元软件提出了一种汽车喇叭声学特性的仿真分析方法,试验结果验证了该方法的可行性和准确性.进而分析了喇叭参数对声学特性的影响规律.