对任一一个非正弦周期电流的有效值，其计算公式为

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SQL Error: select id,body,options from ***_enewstiku where sourceid='32677' and id < 2599484 and id<>'2599484' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='32677' and id > 2599484 and id<>'2599484' order by id asc limit 5