predic object dm design dsgr model facad transit dm problem object tr dm object model facad trigger tr object model facad guard tr object dv model facad target tr model facad pseudost dv problem wfr transit omg uml object model facad kind dv model facad equal pseudost kind model pseudost kind join problem trigger model facad model facad length trigger problem guard model facad express model facad bodi model facad express model facad bodi model facad express length guard problem problem 