简介:Atemperaturesensorbasedonpolarizationnon-reciprocity(PNR)infiber-opticSagnacinterferometer(FSI)wasproposed.Theexperimentalstudywasmadeprimarilyandtheresultsagreewiththeorywell.Discussionshowsthatthiskindoftemperaturesensorcanachievehighprecisionandhavegreatapplicationpotential.
简介:ChinesegeographerLiDaoyuanwasprobablythefirstperson,about1:500yearsago,todiscoverHelanshanrockengravings.Inthefifthcentury,LifraveledextensivelythroughoutChinatoconductgeographicalsurveys.HediscoverdetherockengrayingsalongtheriverbedoftheYellowRiver.HewroteabouthisdiscoveriesinhisCommentaryontheWaterwaysClassics.Liisfirstknownpersontohaverecordedrockengravings.China,ofcourse,wasthefirstcountryknowntorecordrockengravings.The10,000rockengravingsontheHelanshanMountainshavebeendesignatedworldculturalheritagerelics.