选择性采样

同时，研究基于报文长度的选择性采样方法和系统采样方法对TRW算法检测性能的影响。

At the same time , this thesis compares the detection performance of the scan detection algorithm TRW in the selective sampling method based on the packet length and the system sampling method .

实验结果表明，在确保两种采样方法采样前后报文数相等的情况下，基于数据报文长度的选择性采样方法对TRW算法的检测性能影响较小，能够获得更高的扫描成功检测率。

The experiment results show that on the condition that the packets number is equal before and after sampling , the selective sampling method based on the packet length generates less influence on the detection performance of TRW and can obtain high accuracy of scan detection .

同时，针对已有的基于数据报文长度的选择性采样方法，从理论上分析了其对扫描检测算法性能的影响。

Meanwhile , to the known selective sampling method based on the length of the packet , this thesis analyzes its influence on the performance of the scan detection in theory .

痕量有毒有机物的监测意义重大，传统方法难以达到要求，迫切需要发展高效、经济、有选择性的采样技术，以及与之配套的样品前处理和分析方法。

It is of great important to monitor trace poisonous organic substance , while the traditional approach can not meet the requirements . It cries for high efficient , economic and selectable sampling techniques and its coordinated pretreatment and analysis methods for samplers .