Nrog rau kev nqis peev ntawm 12 lab yuan, peb cov khoom siv thev naus laus zis tshiab tshiab tau npaj txhij los hloov pauv kev lag luam. Qhov chaw ua haujlwm hauv lub xeev no muaj kev ua tau zoo tshaj plaws hauv kev sib xws, permeability, tawg tsis kam, tawv thiab ntau lwm yam tseem ceeb. Cov txheej txheem thev naus laus zis thiab kev tsim khoom siv hauv cov kab no ua kom ntseeg tau tias peb tuaj yeem xa cov txiaj ntsig zoo. Ib qho tseem ceeb tshaj plaws hauv kev ua kom cov neeg siv khoom txaus siab yog qhov sib xws ntawm peb cov khoom. Nrog peb cov kab ntau lawm, peb tau ua tiav qhov zoo sib xws hauv thickness, ceev thiab kev ntxhib los mos. Qib no ntawm precision ua kom txhua yam khoom tsim tau raws li cov qauv zoo tshaj plaws. Peb cov neeg siv khoom tuaj yeem tso siab rau peb los muab cov ntaub ntawv zoo ib yam thiab zoo ib yam kom tau raws li lawv cov kev xav tau.