N-bit Memory Research Articles

A Quantum Algorithm Detecting Concentrated Maps.

We consider an arbitrary mapping f: {0, …, N − 1} → {0, …, N − 1} for N = 2n, n some number of quantum bits. Using N calls to a classical oracle evaluating f(x) and an N-bit memory, it is possible to determine whether f(x) is one-to-one. For some radian angle 0 ≤ θ ≤ π/2, we say f(x) is θ − concentrated if and only if for some given ψ0 and any 0 ≤ x ≤ N − 1. We present a quantum algorithm that distinguishes a θ-concentrated f(x) from a one-to-one f(x) in O(1) calls to a quantum oracle function Uf with high probability. For 0 < θ < 0.3301 rad, the quantum algorithm outperforms random (classical) evaluation of the function testing for dispersed values (on average). Maximal outperformance occurs at rad.

Transparent random access memory testing for pattern sensitive faults

This paper presents a new methodology for RAM testing based on the PS(n, k) fault model (the k out of n pattern sensitive fault model). According to this model the contents of any memory cell which belongs to an n-bit memory block, or the ability to change the contents, is influenced by the contents of any k -1 cells from this block. The proposed methodology is a transparent BIST technique, which can be efficiently combined with on-line error detection. This approach preserves the initial contents of the memory after the test and provides for a high fault coverage for traditional fault and error models, as well as for pattern sensitive faults. This paper includes the investigation of testing approaches based on transparent pseudoexhaustive testing and its approximations by deterministic and pseudorandom circular tests. The proposed methodology can be used for periodic and manufacturing testing and require lower hardware and time overheads than the standard approaches.

A quasi three-dimensional optical memory with n-bit memory cells based on the ellipsometric principle: concept and prototype devices

A concept of an optical memory with n-bit memory cells using ellipsometric read-out is presented. Prototypes with two-bit and three-bit read-only memory cells were fabricated by deposition of multilayers consisting of thin metal films and thin amorphous semiconductor films, respectively.

An Optimal Algorithm for Testing Stuck-at Faults in Random Access Memories

This correspondence presents an optimal algorithm to detect any single "stuck-at-i," "stuck-at-O" fault and any combination of "stuck-at-I," "stuck-at-O" multiple faults in a random access memory using only the n-bit memory address register input and m-bit memory buffer register input and output lines. It is shown that this algorithm requires 4 X 2n memory accesses.

An Algorithm for Testing Random Access Memories

This correspondence presents an optimal algorithm to detect any single stuck-at-1 (s-a-1), stuck-at-0 (s-a-0) fault in a random access memory using only the n-bit memory address register input and m-bit memory buffer register input and output lines. It is shown that this algorithm requires 4 X 2nmemory accesses.