fig node given layer repres given model element fig node portion associ return prefer fig edg portion fig node ig edg search fig node act edg port return param lai layer contain fig param model element model element present fig node present model element fig node node present layer lai object model element model element model element suppli object fig lai content edg fig fig node fig node fig owner equal model element fig node fig object fig lai content edg fig fig edg model element model element equal fig edg model element fig owner fig edg model element fig edg port 