青藏线生活污水处理技术试验研究

青藏线地处青藏高原，生态环境十分脆弱，污水排放要求高。因为高寒缺氧，污水温度低，限制了生物法在污水处理中的应用，需要研究适应青藏线情况的污水处理的新技术和工艺。根据青藏线类比水质检测情况和设计要求，采用了化学混凝膜过滤加催化电氧化的物化工艺流程进行现场试验。结果表明，处理后的污水水质达到了CJ3020-93《生活饮用水水源水质标准》二级标准。     

预应力混凝土斜拉桥悬臂施工的拉索式长挂篮新构思

在预应力混凝土斜拉桥主梁的悬臂施工中 ,经常遇到在浇注混凝土过程中发现标高误差无法调整这一难题 ,介绍了拉索式长挂篮的新构思 ,即将挂篮设计成简支受力结构。拉索式长挂篮由贝雷桁架片、万能杆件以及非标构件组合在一起 ,利用贝雷片用销子连接存在间隙的特点 ,实现上述构思。该挂篮经过一大跨预应力混凝土斜拉桥的施工应用 ,取得了良好的效果 ,主要介绍这一挂篮的结构设计与使用情况。     

隧道用混凝土耐久性问题

隧道中混凝土常受到侵蚀性地下水的侵蚀面破坏，分析了侵蚀的原因和机理，提出了提高隧道混凝土耐久性的措施。     

基于循环分辨分析的湍流特征参数计算法

采用不同的孔板结构和不同的驱动电机转速在定容燃烧弹内生成具有不同的湍流特性参数的气流 ,并用热线风速仪进行了测量。在循环分辨分析的基础上 ,计算分析了它们各自的湍流强度、积分时间尺度和时频谱密度。结果表明 ,电机转速越大 ,孔板总通孔面积越小 ,则湍流越强 ,积分时间尺度越小 ;对于不同的孔板结构和电机转速 ,湍流能量分布明显不同。     

The ‘safety in density’ effect for cyclists and motor vehicles in Scandinavia: An observational study

Safety in density (SID) potentially explains the safety in numbers (SIN) phenomenon by positing that ‘the SIN effect can be reproduced simply through encouraging behaviour that leads to the formation of higher-density cyclist groups’. The study further explores this hypothesis using event-based exposure, queues and groups of road users. Using three different definitions of encounters between road users, these were manually counted at signalized intersections, and their relationship to traffic volume was assessed. Based only on the frontmost motor vehicle in a queue and one cyclist among the several passing in front of that vehicle, the results show a less than linear relationship between meetings and traffic volume. An increase in the number of cyclists entails a general increase in cyclists passing in front of each motor vehicle, and an increase in motor vehicles increases queue lengths. However, crash data from the Swedish accident database (STRADA) show that it is exceedingly rare for multiple cyclists to be injured in the same crash. Together with results from a crash-encounter model, this suggests that the SID hypothesis may help to explain SIN     

Experimental investigations on continuous regenerative anti-lock braking system of full electric vehicle

Functions of anti-lock braking for full electric vehicles (EV) with individually controlled wheel drive can be realized through conventional brake system actuating friction brakes and regenerative brake system actuating electric motors. To analyze advantages and limitations of both variants of anti-lock braking systems (ABS), the presented study introduces results of experimental investigations obtained from proving ground tests of all-wheel drive EV. The brake performance is assessed for three different configurations: hydraulic ABS; regenerative ABS only on the front axle; blended hydraulic and regenerative ABS on the front axle and hydraulic ABS on the rear axle. The hydraulic ABS is based on a rule-based controller, and the continuous regenerative ABS uses the gain-scheduled proportional-integral direct slip control with feedforward and feedback control parts. The results of tests on low-friction road surface demonstrated that all the ABS configurations guarantee considerable reduction of the brake distance compared to the vehicle without ABS. In addition, braking manoeuvres with the regenerative ABS are characterized by accurate tracking of the reference wheel slip that results in less oscillatory time profile of the vehicle deceleration and, as consequence, in better driving comfort. The results of the presented experimental investigations can be used in the process of selection of ABS architecture for upcoming generations of full electric vehicles with individual wheel drive.     

航海教育模式及航海院校管理体制的比较研究

随着ＳＴＣＷ 新公约的生效和实施,航海教育改革在世界范围展开。本文从航海教育模式和院校管理体制两个视角比较研究国内外航海教育的经验和特点,阐述中国航海教育改革的必要性和迫切性     

鞍区显微外科解剖

选用40例成人尸头标本,在手术显微镜下对鞍区周围结构进行了观察。为经额和经蝶两种垂体手术径路提供了有关解剖学依据。主要结果如下:1.视交叉位置,82.5%属正常型,7.5%属后置型,均为经额径路的适应型。但前置型(10%)则不适应于经额径路施术;2.测量了两侧视神经颅内段内侧缘间距及夹角。间距及夹角越小,经额径路越难施行;3.两侧颈内动脉间距以平前床突平面处最窄;4.观察了各海绵间窦。出现率基底窦为100%,前间窦为75%,下间窦为40%后间窦为33.3%。在前、下间窦较大的个体施行经蝶径路可能出现困难。     

碳纤维布加固钢筋混凝土梁挠度的一种计算方法

本文研究了碳纤维布加固性能,利用钢筋混凝土结构设计中的梁理论,推导并验算了粘贴碳纤维布加固钢筋混凝土梁挠度的计算公式方法,分析了影响碳纤维布加固钢筋混凝土梁挠度值大小的因素。     

有软弱夹层岩体边坡的稳定性评价

对发育多个规则软弱夹层的岩体边坡稳定性评价方法进行了探讨。在塑性极限分析的基础上，采用机动位移法，提出可以用能量系数作为稳定性评价的标准，并推导了相应公式。通过川藏公路上一个典型滑坡实例的稳定性分析，与极限平衡法进行了对比，证明了本方法的可行性。