SS-1型地震开关的研制

The development of SS 1 seismic switch

地震报警系统的开发与部署已受到广泛的关注，地震开关是其中关键的技术手段。研究表明：地震发生的Ｐ波与Ｓ波具有不同的传播速度与振动方式，Ｓ波是造成震灾的主要原因而其传播速度要比Ｐ波慢得多。根据Ｐ波振幅与震灾的关系及其振动方式、频率域、时间域的特征，可以从干扰背景中检出地震时首先到达的Ｐ波，如符合判据，就发出报警信号及控制命令：疏散人员，切断次生灾害源，达到减灾的目的。通过响应调整可以排除一些人为的、自然的干扰因素，采用窗口式阈值检测及变时间窗触发判决技术，提高了Ｐ波的检测准确率。测试表明，性能达到了预期的目的。

The development and deployment of earthquake warning system have been paid more attention to recently,in which the seismic switch is a key tool. The results studied shows: the P wave and S wave generated while an earthquake occurred have different propagation velocity and vibration mode, the S waves do all the damage but they travel from the earthquake epicentre more slowly than the P waves. The P wave which arrives firstly can be detected from the background on the basis of the relation between P wave′s amplitude and earthquake disaster, and P wave′s vibration mode, its features in frequency domain and time domain. If it is in accordance with the criteria, an earthquake warning signal and control command will be output to shut down secondary sources which causes the earthquake disaster and to disperse the population, therefore the goal of reduction to earthquake disaster can be reached. The interferences caused by human activity and natural factor can be decreased by means of the response forming technique; using window threshold detection and changable time window triggering decision techniques the P wave′s detection accuracy can be improved. The test results given show the expected performances have been achieved.