Discussion on dynamic reliability tolerance design technology of electromagnetic relay

Reliability tolerance design of electromagnetic relay during its design period plays an essential role in guaranteeing the consistencies of reliability and output characteristic. The reliability tolerance design can ensure that the products would work well under the influence of disturbing factors (including internal interference, external interference, and machining dispersion). Com- pared with static characteristic, dynamic characteristic of electromagnetic relay can describe its operating process better. This article researches influence of the three kinds of disturbing factors on the dynamic characteristic of electromagnetic relay based on calculating dynamic characteristic. Then, the dynamic reliability tolerance design method of electromagnetic relay is discussed considering three kinds of disturbing factors. Conclusions reached can help to assure the reliability of electromagnetic relay from the beginning of design.

显微外科与腹腔镜手术治疗精索静脉曲张疗效比较的回顾性研究

目的:对比显微外科与腹腔镜手术治疗索静脉曲张(VC)的临床效果。方法:回顾性分析2018年8月~2020年8月期间在我院接受精索静脉结扎术治疗的75例VC患者,其中接受腹腔镜手术的34例纳为A组,接受显微外科手术的41例纳为B组。观察两组手术及住院指标情况,对比两组手术前后精液质量变化,观察两组术后并发症发生率和复发率。结果:两组住院天数、住院费用组间对比差异无统计学意义(P>0.05)。B组手术时间长于A组,排气时间短于A组,组间对比差异有统计学意义(P<0.05)。手术后6个月,两组患者的精液量均增加,精子密度均增大,精子活率、活动精子总数均升高,精液液化时间均下降,且B组的变化程度大于A组(P<0.05)。B组的并发症发生率小于A组(P<0.05)。A组有2例患者随访期间复发,B组未见有患者复发,两组复发率组间对比差异无统计学意义(P>0.05)。结论:与腹腔镜手术治疗VC相比,显微外科手术能更有效地改善精液质量、缩短排气时间、降低并发症发生率,虽然手术时间稍长,仍属于较为可靠的术式。