In secret sharing schemes a secret is distributed among a set of users P in such a way that only some sets, the authorized sets, can recover it. The family Γ of authorized sets is called access structure. Given such a monotone family Γ ⊂ 2P , we introduce the concept of extended access structures, defined over a larger set P ′ = P ∪ P̃, satisfying these two properties: • the set P is a minimal s...

Modern high-performance computing systems and databases are implemented under the assumption that a very large proportion of the data used can now be maintained in volatile memory. In this paper, we compare experimentally two recently proposed self-adjusting access structures that can be used to organize data in such settings, namely, the Skip-List (SL) and the Binary B-Tree (BB-Tree). We exami...

Information security has become much more important since electronic communication is started to be used in our daily life. The content of the term information security varies according to the type and the requirements of the area. Secret sharing schemes are introduced to solve the problems for securing sensitive information. In this paper, we review our proposed hierarchical and compartmented ...

We will present some ideas about sharing a secret in a monotonic access structure. We show the relations which occur between the method of encrypting a monotonic access structure with the use of basis sets or maximal unprivileged sets, and that based on a logical formula (used by Benaloh and Leichter in [1]). We will also give some facts connected with the problem of security, including the asp...

In this paper a novel handoff decision algorithm for the mobile subsystem of tactical communications systems is introduced. In this algorithm, handoff decision metrics are: received signal strength measurements from the access points, the ratio of the used capacity to the total capacity for the access points, and relative directions and speeds of the mobiles to the access points. We use a fuzzy...

Tremendous progress has been made experimentally in the hadron spectrum containing heavy quarks last two decades. It is surprising that many resonant structures are around thresholds of a pair hadrons. There should be threshold cusp at any $S$-wave threshold. By constructing nonrelativistic effective field theory with open channels, we discuss generalities behavior, and offer an explanation abu...

changes in dynamic properties of structures indicate occurrence of damages in the structures. in this paper, a new two stage algorithm for damage detection of large structure is introduced. a modified residual force method is utilized to locate the damage regions in structures, especially barrel vaults, and then the enhanced charged system search (css) algorithm is used to quantify the amount o...