Method to calculate resistance of high-speed displacement ship taking the effect of dynamic sinkage and trim and fluid viscosity into account

A method is presented to calculate the resistance of a high-speed displacement ship taking the effect of sinkage and trim and viscosity of fluid into account. A free surface flow field is evaluated by solving Reynolds averaged Navier-Stokes (RANS) equations with volume of fluid (VoF) method. The sinkage and trim are computed by equating the vertical force and pitching moment to the hydrostatic restoring force and moment. The software Fluent, Maxsurf and MATLAB are used to implement this method. With dynamic mesh being used, the position of a ship is updated by the motion of ??ship plus boundary layer?? grid zone. The hull factors are introduced for fast calculating the running attitude of a ship. The method has been applied to the ship model INSEAN2340 for different Froude numbers and is found to be efficient for evaluating the flow field, resistance, sinkage and trim.     

Animal experiment of viscose carbon fiber based C/C composites applied in bone fracture intramedullary fixation

The animal experiment of viscose carbon fiber based C/C composites applied in bone defection intramedullary fixation was carried out in New Zealand white rabbits. The histological observation on the 100th day after surgical operation indicated that the experimental animals recovered well and the bone defect area was reconstructed by new bone trabecula. Immunohistochemical observation of leukocyte common antigen and macrophage suggested that intramedullary fixation materials did not induct any chronic toxicity reactions such as inflammatory reactions, macrophage reactions and formation of granulation tissue. The tissue compatibility of this material was excellent. Meanwhile, the impurity element species and the biological toxic element content of viscose fiber based C/C composites were determined by atomic fluorescence analyzer and inductively coupled plasma atomic emission spectrometry. The results reveal that there are few biological toxic elements in the viscose fiber based C/C composites and it can satisfy the constituent demands of surgical implants.     

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吸取社会力模型中行人运动受到社会力支配的思想,综合考虑行人之间的相互影响,建立了面向大型铁路客运枢纽环境的乘客行为仿真模型.针对人群集散时行人之间的差异性,依据目标驱动力及行人与行人或障碍物之间的心理排斥力、挤压力、摩擦力,动态改变行人的运动方向和速度.引入行人防止穿透决策规则,消除行人重叠现象.采取目标点局部极小化原则,设置辅助目标点,解决行人与环境之间动态避碰和绕行问题.以北京南站高架层为仿真对象,针对不同客流到达率对行人集散的影响进行计算机仿真并加以分析,从而对模型进行校核检验,表明该模型具有合理性和有效性.     

基于人与环境交互作用的交通枢纽导向标识布局评估

为优化轨道交通枢纽的导向标识布局,提升运营效率与服务水平,分析了人与空间环境交互作用下旅客寻路行为与导向标识的交互特性,在此基础上,利用元胞自动机建模思想,构建了旅客寻路行为仿真模型,建立了标识布局评估指标体系,通过输入客流、设施设备等参数,应用GSign系统分析了标识引导下旅客寻路效果,提出了动态仿真定量评估方法.通过北京南站典型场景仿真试验进行了实证研究,结果表明:对典型进站、出站及换乘流线的标识优化后,旅客平均走行速度分别提高了4.0%、3.2%和13.3%;仿真模型输出结果与实际结果的平均相对误差约为7%.      

环长白山旅游公路观景台建设研究

针对我国自驾游发展迅速的特点,首次提出了新时代旅游公路建设的新理念,即由传统强调交通功能的"旅游公路",转变为强调游览功能的"公路旅游";结合环长白山旅游公路工程实践,首次系统研究并提出了基于"保护自然生态、利用自然风景、展现地域文化"的观景台选址、设计、施工技术。     

A new solution to the inverse position analysis of the redundant serial robot

A new solution to the inverse position analysis of the redundant serial robot is presented. The inverse position analysis problem of the redundant serial robot is transformed into a minimization problem and then the optimization method is adopted to solve the nonlinear least square problem with the analytic form of a new Jacobi matrix. In this way, the inverse solution of the redundant serial robot can be searched out quickly under the desired precision when the positions of the three non-collinear end effector points are given. The inverse position analysis of the 7R redundant serial robot is illustrated as an example and the simulation results verify the efficiency of the proposed algorithm.     

基于区位重要度的县乡公路网交通生成预测方法研究

通过分析县乡公路网建设与社会经济发展的相互关系,结合县乡公路网的特点,从经济发展度、连通度和导向度三个方面定义交通小区的重要度,建立基于区位重要度的县乡公路网交通生成模型。永定县县乡公路网规划实例使得该方法的合理性和有效性得到了验证。     

氯盐对水泥海排灰结合料影响的SEM试验研究

通过海排灰中氯离子对水泥海排灰结合料微观结构的影响研究,揭示水泥海排灰结合料强度形成过程.     

斯太尔汽车电源电路分析

电源电路组成斯太尔汽车电源系统主要由蓄电池、交流发电机、充电指示灯、钥匙开关和电源总开关等组成。交流发电机斯太尔汽车采用内置调节器式九管整体交流发电机,其结构如图1所示,内部电路如图2所示。它具有4个接线端子：“B＋”端子通过启动机30端子接蓄电池正极;“D＋”端子接充电指示灯;“99端子发电机上搭铁;“W”端子接发动机电子转速表（仪表盘上）。     

电流变阻尼半主动控制悬架系统的设计

汽车悬架减振器对于保证车辆的乘坐舒适性和安全稳定性都具有重要作用,但目前普遍应用的被动式减振器因其力学性能不能调节,存在只能在两种性能之间折衷的先天不足,而智能半主动悬架系统方案基于“大系统多级递阶——子系统神经网络自适应”控制算法。并利用MATLAB＋Simulink对新型智能半主动悬架系统进行了仿真试验．试验结果表明系统在实现了提高车辆乘坐舒适性能的同时兼顾了安全稳定性的目的。同时由于采用电流变液减振器,使系统本身具有实时采集、响应迅速、智能化、减振降噪效果好等特点。