车载ADAS传感器毫米波雷达解析

ADAS-汽车驾驶辅助系统正在当前的汽车市场中迅速普及。车载雷达作为ADAS系统的重要组成,其技术发展直接影响着汽车智能化进程。毫米波雷达因为其波长的物理特性不受恶劣的环境影响,同时相比激光雷达又有较大的价格优势,已经成为当前厂家的首选。与24 GHz传感器相比,77 GHz传感器的分辨率和精度更高,体积小,正逐渐成为当前汽车领域的主流传感器。同国外雷达传感器供应商相比,国内车载毫米波雷达仍属于起步阶段,国内企业要在市场上与外企竞争并占有一席之地还有很长的路要走。     

路面基层中冲击震动波传播特性的微震试验研究

在试验路段,通过试验模拟车辆对路面的行车作用,利用HZ-MS48型微地震监测系统采集微地震波,并对微地震信号进行处理和分析。阐述微震数据采集试验的方案及过程,对几种微地震波形进行分析对比,研究冲击震动波在路面基层中的传播特性。同时,以其中一个典型微地震事件定位为例,验证微地震监测的定位精度,为交通车辆监测提出一种新思路。     

JL-902型机车柴油机燃烧系统分析仪的研制及应用

讨论了JL-902型机车柴油机燃烧系统分析仪的系统组成、结构特点、现场测试数据,并对数据进行了分析和讨论。通过对测试的示功图和高压油管压力波的分析能够得出柴油机燃烧系统的基本性能参数,并为柴油机提供了一种新的测试设备。     

基于ENC的海域可视化研究

介绍符合IHOS-57标准的电子海图的数据模型及其文件结构，利用ENC中离散的海测水深点，海岸线数据和0PENGL中的相关技术生成符合Delaunay三角网规则的海底表面模型、各种航标以及岸上灯塔的灯光和动态的海面。     

Higher-order boundary element method for the interaction of a floating body with both waves and slow current

A hybrid boundary element method is suggested to solve the problem of the interaction of floating structures with both waves and slow current. A pulsating source and its mirror image referring to the sea bottom are adopted as the Green's function. The velocity potentials are expanded into an eigenfunction expansion in the outer region of the fluid domain while higher order elements are used to discretize the boundary surface surrounding the inner region. The method is validated by comparing calculated results for a circular cylinder with the semi-analytical solutions. The method is then applied to ellipsoids of various breadth and draft to investigate the influence of body shape on the wave drift damping.     

基于行波效应的大跨度钢-混凝土组合拱桥地震响应分析

研究大跨度结构的地震响应时,有必要考虑地震波的行波效应。针对一种特殊的钢-混凝土组合拱桥进行地震响应研究。以重庆市万县长江大桥为建模依据,使用大型通用有限元软件sap2000建立跨径为420 m的钢-混凝土组合拱桥计算模型,并对该模型多种激励状态进行分析。在一致激励状态下进行几何非线性时程分析,并基于多点激振理论和相对位移法,采用7种不同的时差对计算模型进行行波效应下的地震响应分析。对比研究表明行波效应对大跨度桥梁结构地震响应有很大影响。     

船模过驳波浪运动检测试验研究

利用研究构建的船舶波浪运动检测系统和检测数据处理及有效积分的方法,在波浪试验室进行了船模过驳波浪运动试验,并对试验数据进行了分析处理.分析指出,舰船过驳时应在迎浪的情况下进行,并且应适当调整两船相对波浪的位置,尽量使两船的波浪运动相位同步.     

Nonlinear hydrodynamic responses of submerged moving payload in vicinity of a crane barge in waves

The wave interaction with a submerged cylindrical payload subjected to constrained motions in presence of a nearby floating crane barge is investigated in the three-dimensional numerical wave tank using a fully nonlinear potential flow model in the time domain. Numerical simulations are carried out to investigate the hydrodynamic features of this submerged payload under pendulum motion in water waves as well as while it moves towards the sea bed at a constant vertical velocity. It is known that the presence of multiple side by side floating bodies in waves can create significant drift motion. In the present study the similar drift motion is observed for the side by side floating barge and submerged payload and it appears that the submerged payload under constrained motions may face a very large mean drift motion of nearly seven times that of the incident wave amplitude in the beam sea upstream condition. Emphasis is also given towards investigating and understanding the influences of natural frequency of the payload and shielding effect due to the presence of the floating barge. It is found that natural frequency coupled with shielding effect generates remarkable low frequency components in payload responses both in the head sea and the beam sea situations. The effect of different cable lengths, wave maker frequencies and downward moving velocities on payload responses under several geometric setups are studied and compared, and interesting features such as increased low frequency movement of the payload near the natural frequency region and existence of considerable low frequency motions even at a greater depth (while the payload is quite below the free surface) are observed.     

基于波浪增阻的长球首球尾双体风电维护船仿真研究

根据中国海上风电场维护船的使用要求和航行的环境特点,本文选取快速性和耐波性良好的长球首球尾双体船作为风电维护船船型。利用基于CFD的数值仿真方法模拟长球首球尾双体风电维护船在波浪中的纵摇和升沉运动,计算其波浪增阻。研究球首球尾长度和片体干扰对长球首球尾双体船在波浪中阻力性能的影响,为球首球尾双体船以及风电维护船的船型设计与优化提供参考。     

不规则波对方箱浮式防波堤作用的数值模拟

采用线性波浪叠加法对不规则波进行数值模拟,采用时域边界元法对不规则波作用下的方箱浮式防波堤进行数值模拟。首先验证了不规则波的数值模拟的准确性,进而对不规则波作用下固定方箱浮式防波堤的受力进行数值模拟,并与规则波结果进行比较。结果表明不规则波作用下,单位宽度方箱垂向受力最大值要大于水平受力的最大值;与规则波情况相比,方箱的水平向受力变化幅度减小,垂向受力和横摇力矩则幅值增加。