PASS partly overcomes the air-sea boundary problem by circumventing the first of those crossings.
PASS通过绕过第一个交叉点克服了海空的边界问题。
英语百科
Boundary problem (spatial analysis)
A boundary problem in spatial analysis refers to a phenomenon in which geographical patterns are differentiated by the shape and arrangement of boundaries that are drawn for administrative or measurement purposes. This is distinct from and must not be confused with the boundary problem in the philosophy of science that is used as a synonym for the demarcation problem.