基于PXI的多普勒速度声呐测试系统设计

根据多普勒速度声呐的测试需要,在分析了多普勒速度声呐测速原理的基础上,对测试方法进行了研究.设计了基于PXI总线技术的波形采集和回放模块,并采用声对接的方式对声呐系统进行测试.测试结果表明,该系统完全满足测试要求,同时具有通用性、高效性和易用性等特点,具有较好的实用价值.     

磁道钉导航的横向偏差等值线及其应用研究

阐述了基于磁道钉导航的车辆定位原理;利用磁道钉磁感应强度公式计算磁道钉周围磁场,生成以磁感应强度X和Z方向分量为横、纵轴的横向偏差等值线方程;基于此等值线方程,得到磁感应强度X,Z方向分量数据对所对应的横向偏差的计算方法,并给出实例验证.     

A new GPS deformation monitoring algorithm applied to Donghai Bridge

A real-time, long-round global positioning system (GPS) bridge-deformation monitoring technology was proposed, which processes the carrier phase of multiple GPS receivers in an operation center. It was demon- strated an extended Kalman filter with triple differential ionospheric-free measurement (EKF-TIF) which can eliminate the ionospheric delay, whiten the TIF noise and optimize the results of EKF, consequently, achieves a better performance than existing real time kinematic (RTK) solution. An experiment, which takes an active ionosphere condition into consideration, proves the feasibility of this system by comparing its records to that of a traditional RTK solution, practically, the system installed on the Donghai Bridge has survived a non-break running for five months. The analysis to the monitoring records shows the system achieves the designed accu- racy and reliability.     

轨道衡超偏载检测系统设计与实现

设计了轨道衡超偏载检测系统。利用列车车号识别系统自动识别车辆信息，车辆上衡后通过定位系统将其准确定位在衡器的中间位置上，在装车过程中实时显示车辆偏载信息，便于及时采取措施纠正偏载问题。详细描述了轨道衡超偏载检测系统的设计方案、主要功能模块及软件系统开发中的几个关键技术。     

中远船务10.5万吨穿梭油轮简介及应用前景

随着地球上内陆石油资源的逐日枯竭，人类逐渐转向对深海技术的发展和能源的研究。大量深海中的海洋油田开采需要大量穿梭油轮来进行辅助运输。基于这样的市场需求，中远船务自行设计和建造了10.5万吨穿梭油轮。     

动力定位系统DPS在海洋工程中的广泛应用

动力定位系统,主要是通过计算机系统测算出风速,海浪颠簸度等,调节各个推进器转速等通过激光定位仪,差分定位仪,做到精确定位.目前已经广泛应用与海洋工程中,例如钻井平台,配套工作及生活平台以及穿梭油轮等.     

TDOA/DR组合系统定位算法及仿真研究

GPS/DR组合导航在户外GPS信号较好的情况下,可以提供精度较高的定位导航,但人的活动范围不仅仅是户外,会经常穿梭、停留于各种建筑物中。此时,GPS信号几乎无法获得,DR会因长时间得不到修正而导致发散,因此,GPS/DR系统无法在室内提供长时间高精度的导航信息。基于上述原因,文章研究基于到达时间差（TDOA）的定位算法,利用超声传感器实现室内TDOA定位,并与DR系统进行组合,校正并改善DR系统误差发散问题,以增强导航系统的定位能力。     

Acoustic radiation analysis based on essential solution of Green’s function

The principle objective of the paper is to study the acoustic radiation problem of the 3D space domain with control boundary. By using the conformal transformation theory, the Green’s function for acoustic point source in the control domain space is obtained. With it, the expression of acoustic radiation function of the control domain is formed. Discussion about the acoustic radiation of pulsating sphere in right-angle space is drawn in the end, including the acoustic radiation directivity effect by the boundary characteristics, acoustic radiation frequency and acoustic source location. Numerical results show that: for the lower frequency radiation, the infection of free surface is significant; for the high frequency radiation, the infection of location is significant on the contrary. The research provides a new method for boundary characteristic problem of the structural-acoustic acoustic.     

温州瓯江北口大桥中塔钢沉井定位着床技术

温州瓯江北口大桥主桥为(215+2×800+275)m的三塔双层钢桁梁悬索桥,中塔采用沉井基础,沉井平面尺寸为66m×55m,高68m,其中,钢沉井高59m。为实现钢沉井的精确定位着床,采用锚墩+重力锚相结合的定位技术,在水流流速和风速较小的时间段,采用向井壁和隔舱内快速注水实现钢沉井快速着床。在钢沉井初定位、精定位及注水着床期间,运用实时监测技术,对钢沉井几何姿态及底面应力进行了实时监测,并及时对沉井偏位、扭转等采取纠偏措施。结果表明,着床后钢沉井中心点顺桥向偏北侧8.0cm,横桥向偏上游侧21.9cm,平面扭转角为-0.24°,钢沉井几何姿态控制良好。     

Terrain-based road vehicle localisation using particle filters

This work develops a particle filter algorithm to localise a vehicle in the direction of travel without the use of GPS. The inputs to the algorithm include a terrain map of road grade, pitch measurements from an in-vehicle pitch sensor, and wheel odometry. Simulations and experiments at The Thomas D. Larson Transportation Institute test track are used to demonstrate the algorithm, observe the speed of convergence, and to determine key parameters for practical implementation. The results indicate that the method can quickly localise a vehicle with 1 m accuracy or better. Experiments over 5 km along Highway 322 in State College, Pennsylvania, were also used to demonstrate the algorithm.