Physiological Systems Experiment 
Philippine Stock Exchange 
Pacific Stock Exchange 
Passive Seismic Experiment 
Power Sourcing Equipment 
Payload Support Equipment 
Peculiar Support Equipment 
Packet Switch Exchange 
Personal and Social Education 
Power Supply Electronics 
Power System Electronics 
Programming Support Environment 
Project Support Environment 
Packet Switching Exchange 
Packet Switching Exchanges 
Page Size Extension 
Pale soft exudative pork 
Parabolized Stability Equations 
Payload Service Equipment 
Payload Servicing Equipment 
Payload Support Engineer 
Payload Systems Engineer 
Phase Separation Experiment 
Philadelphia Stock Exchange 
Physical Security Equipment 
Please 
Power System Equipment 
Predicted Scientific Events 
Pressurized solvent extraction 
pressurized subcritical experiment