perfect model of ship magnetism 完备船磁模型

heading survey of ship magnetism 船磁方位测量

ship permanent magnetism 永久船磁性 ; 永久船磁

ship ' s magnetism 船体磁性

ship s magnetism 船体磁性

ship induced magnetism 感应船磁

ship subpermanent magnetism 半永久船磁性

athwart ship permanent magnetism 横向永久船磁

sub-permanent magnetism of ship 船舶亚固定磁性