We survey recent results on the existence of polynomial time approximation schemes for some dense instances of NP-hard optimization problems. We indicate further some inherent limits for existence of such schemes for some other dense instances of the optimization problems. more >>>

We study the problem of assigning different communication channels to acces points in a wireless Local Area Network. Each access point will be assigned a specific radio frequency channel. Since channels with similar frequencies interfere, it is desirable to assign far apart channels (frequencies) to nearby access points. Our goal ... more >>>