Arc characteristics during the instability stage on transverse magnetic field contacts

The arcing process greatly affects the breaking ability after current zero. The instability stage is the transition stage from the ignition to the movement stage, which affects the arc movement characteristics. In this paper, the arc characteristics during the instability stage on spiral-type contacts were investigated using a high-speed video camera. A multi-column parallel instability mode and a single-column instability mode were found during the instability stage. The arc appearance and constriction degree changed rapidly. The arc voltage usually increased accompanied by fluctuations. In addition, it was found that the current significantly influenced the arc mode and duration in the instability stage. With increased peak current, the probability of a single-column instability mode increased, and the fluctuation range and average time decreased.     

基于知识图谱的电网科技评审专家推荐方法研究

为了提高电网科技项目咨询评审专家遴选效率,提出基于知识图谱的电网科技专家推荐方法。首先构建包含专家、项目和研究领域的电网科技知识图谱,再通过TF-IDF算法提取专家论文和项目领域的关键词,基于音形码编码规则对关键词进行重新编译并通过编辑距离映射至图谱节点,最后利用余弦相似度计算得到专家与项目的最佳匹配组合。以某电网科技项目评审专家推荐为算例,通过K近邻法验证了所提方法的有效性,可在一定程度上增强电网科技项目评审专家遴选质量与效率。