collaborative spectrum sensing (css) is an effective approach to improve the detection performance in cognitive radio (cr) networks. inherent characteristics of the cr have imposed some additional security threats to the networks. one of the common threats is primary user emulation attack (puea). in puea, some malicious users try to imitate primary signal characteristics and defraud the cr user...

The number of threshold functions of eight variables is counted by ILLIAC II, the computer of the University of Illinois. Sets of optimum weights of majority elements realizing these functions also are investigated. Actually, canonical positive self-dual threshold functions of nine variables are investigated instead of directly investigating threshold functions of eight variables because it is ...

This paper studies a single-stage production system, two-stage production system where specification limits are designed for inspection. When quality characteristics fall below a lower threshold or above an upper threshold, a decision is made to rework or scrap the item. The target is to determine the optimum target for a process based on rework or scrap costs. In contrast to previous studies, ...

Alternating current threshold excitation of space-clamped squid giant axons was measured as a function of frequency, external calcium concentration, temperature (from 10 degrees to 35 degrees C), and hyper- and depolarizing steps. In normal axons there is usually an optimum frequency at about 120 Hz, at which the threshold is a minimum. The threshold rises at both lower and higher frequencies t...