中低速磁浮列车地面综合监测系统的设计与实现

状态监测是磁浮列车运营安全的重要环节。首先对列车地面综合监测系统需求作了简要分析,之后在对系统的总体设计进行介绍的基础上,根据具体情况,分析选用相应的数据通信方式,协调相互之间数据传输协议,完成了集车辆、地面变电站、道岔等子系统一体的地面综合监测系统的设计与实现。目前这套系统在唐山1.5km长的磁浮试验线上运行良好。     

实时通信在调车作业中的设计与实现

调车作业中普遍采用了无线平面调车设备,配合逐渐推广的计算机联锁系统,使调车作业在进路间和进路内的安全保障进一步提高。但受到站内轨道电路的制约,加上地面调车信号与机车监控装置无法联锁,实际调车做业仍依靠司乘人员确认地面信号,导致调车机车“冲、挤、脱”以及冒进事故时有发生。此外,大量低效的手工作业,致使机车状态监测、事故分析等问题也已成为目前调车作业的盲点。     

S.M.W支护结构的大变形数值分析

针对可回收的Ｓ．Ｍ．Ｗ支护结构,文中基于Ｔ．Ｌ坐标,建立了初始构形的大变形增量有限元方程。引入自修正选代算法,用编制ＦＬＳＡＣ大变形程序,对Ｓ．Ｍ．Ｗ支护结构的受力和变形特征进行了分析。为支护结构设计和选取支护结构参数提供了依据。     

税收政策对新能源汽车企业发展的影响研究

现如今,国家提倡环保,各行各业为寻求新型的发展之路都做出了相关的改进.针对汽车行业而言,有必要研发新能源汽车,唯有促进技术创新,才能令新能源汽车产业获得更好地发展,这也是当前汽车产业发展的主要方向.站在政府的角度,为了激励企业展开研发投入,通常会采取税收优惠政策,推出有利的扶持政策,比如税收优惠政策,以便新能源汽车企业...     

海洋平台新型配电网络研究

本文结合现有海洋平台电力分配系统,提出了一种环形配电网络与直流配电技术相结合的新型配电网络,并分析这种新型配电网络的优点和关键技术。     

Experimental study on hydrodynamics of L-type podded propulsor in straight-ahead motion and off-design conditions

Experimental tests were conducted to evaluate the hydrodynamic performance of an L-type podded propulsor in straight-ahead motion and off-design conditions using an open-water measuring instrument developed by the authors for podded propulsors, a ship model towing tank, and under water particle image velocimetry (PIV) measurement systems. Under the three types of conditions, the main parameters of an L-type podded propulsor were measured, including the propeller thrust and torque, as well as the thrust, side force, and moment of the whole pod unit. In addition, the flow field on the section between the propeller and the strut was analyzed. Experimental results demonstrate that the dynamic azimuthing rate and direction and the turning direction affect the forces on the propeller and the whole pod unit. Forces are asymmetrically distributed between the left and right azimuthing directions because of the effect of propeller rotation. The findings of this study provide a foundation for further research on L-type podded propulsors.     

高速公路路基过湿土处理的探讨

从理论和实践方面分析了过湿土对高速公路路基施工的影响,介绍过湿土的处理措施及施工要点。     

Numerical analysis of the soil compaction degree under multi-location tamping

Dynamic compaction (DC) is an efficient soil improvement technique. The previous numerical studies mainly focus on the soil response of single location tamping, but ignore the soil compaction degree under multilocation tamping. In this study, a numerical investigation of multi-location tamping in granular soils is carried out using three-dimensional (3D) finite element model (FEM). The behaviors of the granular soils are described by means of the viscoplastic cap model. The constitutive relationship of the soils is implemented into LS-DYNA and is integrated with 3D FEM for numerical investigation. Then utilizing the field data from the previous studies, we investigate the soil compaction degree at different stages by a case of two basic patterns, and discuss the cause of soil response. Lastly, we evaluate the effect of construction parameters on soil compaction. The simulation results show that the previous tamping affects the soil compaction degree beneath the adjacent tamping location, and the effect is greater near the side of previous location. Meanwhile, the soil compaction degree around the existing tamping crater weakens due to the adjacent tamping. Moreover, the rational selection of DC construction parameters can improve the soil compaction degree, and some hints on the effect of soil compaction are given.     

重型柴油机四气门气缸盖的设计

在经验设计的基础上,采用冷却系统CFD与有限元分析相结合的方法,利用CFD定量分析确定了气缸盖的冷却水量和冷却水分布,利用有限元分析了气缸盖的温度场和疲劳安全系数,优化设计了一重型柴油机的四气门气缸盖,并进行了气缸盖测温和发动机可靠性试验。试验证明,该气缸盖工作可靠,测量的温度与计算的温度基本吻合,证明了气缸盖设计方法的有效性。     

雷达模拟视频和电子海图图像叠加方法

雷达和电子海图是船舶重要助航设备。为了提高船舶航行中的避碰能力,文章提出了一种雷达模拟视频和电子海图图像叠加方法。采集雷达的模拟视频信号、方位信号和触发脉冲,通过A/D转换,利用极坐标与直角坐标变换模型和图像匹配模型,实现雷达和电子海图图像的叠加。试验结果表明,雷达和电子海图图像叠加是辅助船舶安全航行的有效方法,电子海图的海岸轮廓和雷达扫描到的图像能够较好的匹配融合,可以在电子海图底图上实时显示雷达捕获到的目标,提高对船舶周围环境的监控能力。