Prevention of Significant Deterioratio… 
power spectral density 
Personnel Support Detachment 
Physical Sciences Division 
particle size distribution 
Phase-Sensitive Detector 
pore size distribution 
position sensitive detector 
post-source decay 
power spectrum density 
Printer Sharing Device 
Program Support Data 
Programmer's Supplementary Documents 
Protein Sequence Database 
pulse shape discrimination 
Packet Switched Data 
Passive Sampling Device 
Personal Security Detail 
Personnel Services Delivery 
Personnel Services Division 
Personnel Support Detachments 
Phased Space Density 
Photon-Stimulated Desorption 
planning systems division 
Positive Sensitive Detectors 
Power Sliding Door 
Printing Systems Division 
Private sector development 
Professional Standards Department 
Program Structure Diagram