Line integral convolution ( lic ) is one of texture - based methods for vector field visualization . even in the vector direction changing sharply fields , the method can show the direction of the vector field well , and display details of the vector field better . in addition , it can fully disclose the relativity among every spot of the vector field 线积分卷积( lineintegralconvolution ， lic )方法是一种基于纹理生成技术的矢量场可视化映射方法，线积分卷积法能连续反映场中各点切矢，即使在矢量方向变化很大的区域，也能揭示出矢量的方向，可以较好地表达出矢量场的细节。
The noise signal of passing vehicles is gathered with microphone array , and processed off line with the method of wide - band array signal processing , then the estimation of vehicle numbers can be transformed into the estimation of signal source numbers , up and down of the vehicle can be transformed into doa estimation of array signal processing . at the same time , vehicle types are classified using pca method of the pattern recognition based on vehicle noise , and some primarily study is done for vehicle recognition . at last , the result of the experiment proves this method is feasible 对麦克风阵列所采集的车辆行驶时的声音信号，运用宽带阵列信号处理的方法进行离线处理，并将车辆个数的估计转化为阵列信号处理中信号源个数的估计，将车辆上下行的估计转化为阵列信号处理中波达方向变化的估计，进而较准确地估计出了车辆的个数与行车方向；同时对所采集的车辆声音信号应用模式识别中的主分量分析法实现了车辆的简单分类，为实现车型识别作了一些初步的探索。
