关于雷达方面的知识!EFFECTIVENESSOFEXTRACTINGWATERSURFACESLOPESFROMLIDARDATAWITHINTHEACTIVECHANNEL:SANDYRIVER,OREGON,USAbyJOHNTHOMASENGLISHATHESISPresentedtotheDepartmentofGeographyandtheGraduateSchooloftheUniversityofOregoninpartialfulfillmentoftherequirementsforthedegreeofMasterofScienceM