A method and system for interactive patient-specific simulation of liver tumor ablation is disclosed. The organic light emitting diode includes, at least two stacks formed between a first electrode and a second electrode and a charge generation layer including an N-type CGL and a P-type CGL formed between the stacks, wherein the N-type CGL is formed of the anthracene compound. A regular transmission detecting part refers to the transmission history table for every time zone corresponding to the check interval memorized in a setting table. The engaging openings have a plurality of protuberances projecting into the opening, the protuberances providing a reduced area of clearance within the engaging opening.