针对国内外冷却塔风机故障报警装置误报漏报严重问题,在研究主要故障发生机理的基础上,设计了一种用于冷却塔风机的新型故障监控系统。主要监控风机叶片和传动轴失效断裂情况,及时报警停机,避免叶片或传动轴甩出砸坏相关设施的经济损失...针对国内外冷却塔风机故障报警装置误报漏报严重问题,在研究主要故障发生机理的基础上,设计了一种用于冷却塔风机的新型故障监控系统。主要监控风机叶片和传动轴失效断裂情况,及时报警停机,避免叶片或传动轴甩出砸坏相关设施的经济损失。该监控系统采用西门子S7-200系列PLC和WinCC监控软件相结合的监控模式,采用S7-200 PC ACCESS作为OPC服务器实现PLC和WinCC监控软件之间的通讯。生产实践证明,此监测系统明显提高了风机故障监控的可靠性,能够有效地减少风机重大事故的发生,具有良好的推广应用价值。展开更多
Objective: To systematically evaluate the safety, effectiveness and acceptability of FRCu200C IUD. Methods: Electronic and hand searches were used to identify relevant literatures published between April 1988 and May ...Objective: To systematically evaluate the safety, effectiveness and acceptability of FRCu200C IUD. Methods: Electronic and hand searches were used to identify relevant literatures published between April 1988 and May 2006. Included papers were systematically selected and evaluated according to established guidelines of evidence-based medicine. Results: Twenty-two relevant papers were identified, and five of them were included. The cumulative one-year pregnancy rate of FRCu200C was slightly higher than that of MLCu375. The FRCu200C’s cumulative terminated rate due to medical reasons was higher than that of MLCu375 at the end of one-year. During the first year of use, the percentage of the increased amount of menstrual bleeding of FRCu200C was lower than that of MLCu375. The cumulative one-year, two-year and five-year continuation rates of FRCu200C were lower than that of MLCu375. Conclusion: The overall clinical effect of FRCu200C is equal or somewhat inferior to MLCu375. It is recommended that more RCTs (randomized controlled clinical trials) should be done to evaluate its safety, effectiveness and acceptability, and follow-up survey be continued at least five years before the expansion of FRCu200C. And the RCTs should not be carried out by FRCu200C IUD manufacturer.展开更多
文摘针对国内外冷却塔风机故障报警装置误报漏报严重问题,在研究主要故障发生机理的基础上,设计了一种用于冷却塔风机的新型故障监控系统。主要监控风机叶片和传动轴失效断裂情况,及时报警停机,避免叶片或传动轴甩出砸坏相关设施的经济损失。该监控系统采用西门子S7-200系列PLC和WinCC监控软件相结合的监控模式,采用S7-200 PC ACCESS作为OPC服务器实现PLC和WinCC监控软件之间的通讯。生产实践证明,此监测系统明显提高了风机故障监控的可靠性,能够有效地减少风机重大事故的发生,具有良好的推广应用价值。
文摘Objective: To systematically evaluate the safety, effectiveness and acceptability of FRCu200C IUD. Methods: Electronic and hand searches were used to identify relevant literatures published between April 1988 and May 2006. Included papers were systematically selected and evaluated according to established guidelines of evidence-based medicine. Results: Twenty-two relevant papers were identified, and five of them were included. The cumulative one-year pregnancy rate of FRCu200C was slightly higher than that of MLCu375. The FRCu200C’s cumulative terminated rate due to medical reasons was higher than that of MLCu375 at the end of one-year. During the first year of use, the percentage of the increased amount of menstrual bleeding of FRCu200C was lower than that of MLCu375. The cumulative one-year, two-year and five-year continuation rates of FRCu200C were lower than that of MLCu375. Conclusion: The overall clinical effect of FRCu200C is equal or somewhat inferior to MLCu375. It is recommended that more RCTs (randomized controlled clinical trials) should be done to evaluate its safety, effectiveness and acceptability, and follow-up survey be continued at least five years before the expansion of FRCu200C. And the RCTs should not be carried out by FRCu200C IUD manufacturer.
