疏水化合孔栓物对高性能混凝土性能影响的试验及应用

研究疏水化合孔栓物对不同强度等级的高性能混凝土工作性、力学性能及耐久性的影响。结果表明:疏水化合孔栓物可改善新拌混凝土工作性、显著降低混凝土吸水率,混凝土吸水率普遍降低50%以上,同时可提高混凝土抗氯离子渗透性。疏水化合孔栓物降低混凝土早期强度,但对后期强度无明显影响。该内掺型疏水材料在范和港跨海大桥、东华大桥等工程中得到推广应用,显著提高了混凝土结构耐久性。     

基于DSP的实时视频压缩系统的开发

随着电子技术与图像通信技术的迅猛发展，视频压缩技术逐渐规范与成熟，阐述基于DSP的实时视频压缩系统的开发。在概述基于DSP芯片的视频信号采集与处理的原理后，对系统主要硬件的选择进行详尽的分析。简单介绍开发环境和软件的选择。     

牵引变电所全景数据录波方案设计与探索

分析了电力系统录波和牵引供电系统录波的异同,根据牵引负荷的特殊性,结合今后智能牵引供电系统的发展和故障在线诊断及预警系统的构建,提出了适合电力牵引网特殊要求的数据采集方案,并对系统录波方式和数据存储方式提出新观点。     

SPH中改进无网格插值方法比较和精度分析(英文)

In the smoothed particle hydrodynamics (SPH) method, a meshless interpolation scheme is needed for the unknown function in order to discretize the governing equation. A particle approximation method has so far been used for this purpose. Traditional particle interpolation (TPI) is simple and easy to do, but its low accuracy has become an obstacle to its wider application. This can be seen in the cases of particle disorder arrangements and derivative calculations. There are many different methods to improve accuracy, with the moving least square (MLS) method one of the most important meshless interpolation methods. Unfortunately, it requires complex matrix computing and so is quite time-consuming. The authors developed a simpler scheme, called higher-order particle interpolation (HPI). This scheme can get more accurate derivatives than the MLS method, and its function value and derivatives can be obtained simultaneously. Although this scheme was developed for the SPH method, it has been found useful for other meshless methods.