In this paper, we have proposed new variants of the El-Gamal and the Cramer-Shoup encryption schemes. In our schemes, the anonymity property holds even if each user chooses an arbitrary prime q where |q| = k and p = 2q + 1 is also prime. More precisely, our El-Gamal variants provide anonymity against the chosen-plaintext attack, and our Cramer-Shoup variants provide anonymity against the adapti...

A new instantiation of the Cramer-Shoup paradigm for secure encryption is presented, which is built using bilinear map groups. The security is based on the Bilinear Decisional Diffie-Hellman assumption. The recent efficiency improvements introduced in [KD04,GS04] are also applied to our constructions. One of the schemes thereby obtained presents efficiency similar to the most efficient encrypti...

-In this paper we present new approximation expressions for the Cramer-Rao Lower Bound on unbiased estimates of frequency, phase, amplitude and DC offset for uniformly sampled signal embedded in white-Gaussian noise. This derivation is based on well-known assumptions and a novel set of approximations for finite series of trigonometric functions. The estimated Cramer-Rao Lower Bounds are given i...

The Threshold of Toxicological Concern (TTC) is a pragmatic approach in risk assessment. In the absence of data, it sets up levels of human exposure that are considered to have no appreciable risk to human health. The Cramer decision tree is used extensively to determine these exposure thresholds by categorizing non-carcinogenic chemicals into three different structural classes. Therefore, assi...

We propose a new variant of the Cramer-Shoup KEM (key encapsulation mechanism). The proposed variant is more efficient than the original Cramer-Shoup KEM scheme in terms of public key size and encapsulation cost, but is proven to be (still) secure against chosen ciphertext attack in the standard model, relative to the Decisional Diffie-Hellman problem.

The nonlinear estimation problem in navigation using terrain height variations is studied. The optimal Bayesian solution to the problem is derived. The implementation is grid based, calculating the probability of a set of points on an adaptively dense mesh. The Cramer-Rao bound is derived. Monte Carlo simulations over a commercial map shows that the algorithm , after convergence, reaches the Cr...