English to Japanese Other Physics

Coverage analysis

The coverage of BSA(Bovine serum albumin) on HOPG(highly oriented pyrolytic graphite) images and the standard Nanoscope software. The area of BSA coverage could be calculated with the bearing function after the threshold was appropriately fixed. Usually, the threshold was chosen at the midpoint between the height of the substrate and that of BSA film.

上記文中の｢bearing function｣の定訳がわかりません。　閾値が出てきますので、関数系？とも思ったんですが、結局のところわかりません。　

よろしくお願いします。