1 Decoherence-free subspaces, subspace of a system's Hilbert space where the system is decoupled from the environment.  Dynamic Frequency Selection, part of the IEEE 802.11h wireless standard.
The American Psychological Association (APA) is a scientific and professional organization that represents psychologists in the United States.
Best Answer: APA stands for American Psychological Association. The APA Manual is used extensively for people to use as a format guideline for writing research papers. It is very popular because it is so user friendly.