This paper presents a system architecture and the appropriate algorithms for confidential searching of multimedia digital libraries. The proposed scheme uses Middleware service layer that allows pre-processing of raw content with technology owned by the Search Engine, without compromising the security of the original architecture in any way. The specific search algorithms described are a hierar...

This paper describes a method for optimal backtracking Prolog based on failure-bindings of literals. A modified unification algorithm is presented in order to identify all possible causes of failure during execution. Methods to select optimal back-point and the use of Failure Binding Tables at run-time are presented. Forwardand Backwardexecution algorithms are also given. keywords: prolog, inte...

The problem of proving that a propositional boolean formula is satisfiable (SAT) is one of the fundamental problems in computer science. The most popular SAT algorithms are based on the well known Davis-Putnam procedure. There, to guide search, a branching rule is applied for selecting still unassigned variables and computing an assignment to this variable. Additionally, conflict analysis metho...

This paper reviews the connections between Graphplan’s planning-graph and the dynamic constraint satisfaction problem and motivates the need for adapting CSP search techniques to the Graphplan algorithm. It then describes how explanation based learning, dependency directed backtracking, dynamic variable ordering, forward checking, sticky values and random-restart search strategies can be adapte...

We analyze the distribution of computational eeort required by backtracking algorithms on unsatissable CSPs, using analogies with reliability models, where lifetime of a specimen before failure corresponds to the runtime of backtracking on unsatissable CSPs. We extend the results of 7] by showing empirically that the lognormal distribution is a good approximation of the backtracking eeort on un...

This paper investigates a form of algorithm hybridization that combines constraint satisfaction algorithms with local search algorithms. On one hand, constraint satisfaction algorithms are eeective at nding feasible solutions for tightly constrained problems with complex constraints. On the other hand, local search algorithms are usually better at nding solutions that are good with respect to a...

This paper illustrates how a Prolog program, using chronological backtracking to find a solution in some search space, can be enhanced to perform intelligent backtracking. The enhancement crucially relies on the impurity of Prolog that allows a program to store information when a dead end is reached. To illustrate the technique, a simple search program is enhanced. To appear in Theory and Pract...

We describe a general method to obtain quantum speedups of classical algorithms which are based on the technique of backtracking, a standard approach for solving constraint satisfaction problems (CSPs). Backtracking algorithms explore a tree whose vertices are partial solutions to a CSP in an attempt to find a complete solution. Assume there is a classical backtracking algorithm which finds a s...

A new search algorithm, Descending Requirements Search (DESRS), for Distributed CSPs is proposed. The algorithm is composed of two independent phases. In the first phase, agents form a binary hierarchy of groups. The distributed partition algorithm uses a heuristic that prefers to join neighbors that are strongly constrained, into groups. This is done concurrently at all levels of the hierarchy...

A parallel algorithm for solving distributed constraint networks (DCNs) is presented. The DCNs are composed of agents, each holding a local network of constraints, where all agents are connected by constraints. The parallel backtracking algorithm (PBT) initiates multiple search processes (SPs) that operate in parallel. Parallel search processes scan different parts of the search tree, each repr...