in some long term studies, a series of dependent and possibly truncated life-times may be observed. suppose that the lifetimes have a common marginal distribution function. in left-truncation model, one observes data (xi,ti) only, when ti ≤ xi. under some regularity conditions, we provide a strong representation of the ßn estimator of ß = p(ti ≤ xi), in the form of an average of random variable...

A random key pre-distribution scheme based on key updating (RKKU) was proposed, which is effective in wireless sensor networks. Firstly, the base station will randomly distribute some keys, a hash function and some code slices to each node. Furthermore, the RKKU scheme compares with the information of some random key to find the same key, and computes the communication key between two sensor no...

This paper presents a new paradigm to realize cryptographic primitives such as authenticated key exchange and key encapsulation without random oracles under three assumptions: the decisional Diffie-Hellman (DDH) assumption, target collision resistant (TCR) hash functions and a class of pseudo-random functions (PRFs), πPRFs, PRFs with pairwise-independent random sources. We propose a (PKI-based)...

Intrusion-resilient signatures are key-evolving protocols that extend the concepts of forward-secure and key-insulated signatures. As in the latter schemes, time is divided into distinct periods where private keys are periodically updated while public keys remain fixed. Private keys are stored in both a user and a base; signature operations are performed by the user while the base is involved i...

We study random walks whose increments are α-stable distributions with shape parameter 1 < α < 2. Specifically, assuming a mean increment size which is negative, we provide series expansions in terms of the mean increment size for the probability that the all-time maximum of an α-stable random walk is equal to zero and, in the totally skewed to the left case of skewness parameter β = −1, for th...

The NIST codebook-based deterministic random bit generators are analyzed in the context of being indistinguishable from random. Upper and lower bounds based on the probability of distinguishing the output are proven. These bounds imply that the security of the designs are bounded by the codebook width, or more precisely on the property that the codebooks act like a random permutation, as oppose...

Several identity based and authenticated key agreement protocols have been proposed in recent years and all of them have been shown to be non-secure. It remains an open question to design secure identity based and authenticated key agreement protocols. In this paper, we propose an efficient identity-based and authenticated key agreement protocol IDAK using Weil/Tate pairing. A security model fo...

Here we propose an identity based signcryption scheme in the multi-PKG environment where sender and receiver receive public key from different PKG. We also define security models for our scheme and give security proofs in random oracle model.

A cancelable palmprint authentication system proposed in this paper is specifically designed to overcome the limitations of the contemporary biometric authentication system. In this proposed system, Geometric and pseudo Zernike moments are employed as feature extractors to transform palmprint image into a lower dimensional compact feature representation. Before moment computation, wavelet trans...