光通道的衰减是指_点间光传输通道对光信号的衰减值。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30264' and id < 2448251 and id<>'2448251' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30264' and id > 2448251 and id<>'2448251' order by id asc limit 5