competitive displacement principle

Imaginary displacement principle

Virtual displacement

virtual displacement current

virtual displacement theory

Variable Displacement Pump-Fixed Displacement Moto

3Rs principle

Applicability principle

’identity’ principle

’user pays’ principle

“equal time” principle [election broadcasting]

20%~80% Principle

3B principle

3E principle

3R principle

3s principle

3σ principle

4R principle

4R Principle of Green Consumption