We have studied the voltage fluctuations of current-biased, micron-scale magnetic tunnel junctions. We find that the spectral power density is 1/f -like at low frequencies and becomes frequency independent at high frequencies. The frequency-independent background noise is due to Johnson-Nyquist noise and shot noise mechanisms. The nature of the 1/f noise has its origin in two different mechanis...

Barrier synchronization is a crucial operation for parallel systems. Many schemes have been proposed in the literature to achieve fast barrier synchronization through software, hardware, or a combination of these mechanisms. However, few of these schemes emphasize fault-tolerant barrier operations. In this paper, we describe inexpensive support that can be added to network switches for achievin...

Barrier synchronization is a fundamental operation in parallel computation. In many contexts, at the point a processor enters a barrier it knows that it has already processed all work required of it prior to the synchronization. This paper treats the alternative case, when a processor cannot enter a barrier with the assurance that it has already performed all necessary pre-synchronization compu...

We measured the detectability of moving signal dots in dynamic noise to determine whether local motion signals are preferentially combined along an axis parallel to the direction of motion. Observers were asked to detect a signal composed of three dots moving in a linear trajectory among dynamic noise dots. The signal dots were collinear and equally spaced in a configuration that was either par...