中文摘要：

介绍西门子常用工业网络在化工生产中的应用。根据不同网络的特点和现场实际情况,对网络进行规划和使用,使得工业网络不仅满足工业通讯的需要,而且便于日常的维护。

英文摘要：

For cooperative spectrum sensing based on data fusion, the detection threshold and the configuration of relay users have a great influence on the total error probability. To avoid the exhaustive search, two fast algorithms for the best threshold and for the best configuration are proposed. According to the monotonousness of the total er- ror probability, the search algorithm based on dichotomy is applied to approach the best threshold step by step. The greedy algorithm selecting one best user step by step until the total error probability doesn＇ t decrease is also ap- plied. Simulations show the proposed algorithms decrease the search times effectively with a high spectrum sensing performance kept.