operating mode of a control-volume that says that the change in pe rate is negligible
(Forall (?Self) (<=> (Control-Volume-Negligible-Pe-Change ?Self) (And (Control-Volume-Op-Mode ?Self) (Even-Pe Cv-Involved true)))) (Forall (?Self ?Time) (=> (Active ?Time Control-Volume-Negligible-Pe-Change ?Self) (= (Lambda (?T) (If (= ?T ?Time) (Value-At (D-Pe-Rate (Cv-Involved ?Self)) ?T))) 0))) (Forall (?Self ?Time) (<=> (Active ?Time Control-Volume-Negligible-Pe-Change ?Self) (And (Control-Volume-Negligible-Pe-Change ?Self) (Active ?Time Control-Volume-Op-Mode ?Self))))
(Forall (?Self) (<=> (Control-Volume-Negligible-Pe-Change ?Self) (And (Control-Volume-Op-Mode ?Self) (Even-Pe Cv-Involved true)))) (Forall (?Self ?Time) (=> (Active ?Time Control-Volume-Negligible-Pe-Change ?Self) (= (Lambda (?T) (If (= ?T ?Time) (Value-At (D-Pe-Rate (Cv-Involved ?Self)) ?T))) 0))) (Forall (?Self ?Time) (<=> (Active ?Time Control-Volume-Negligible-Pe-Change ?Self) (And (Control-Volume-Negligible-Pe-Change ?Self) (Active ?Time Control-Volume-Op-Mode ?Self))))