Aiming at certificate revocation problem in Public Key Infrastructure(PKI),a solution scheme based on AVL Search Tree(AVLST) is proposed.

In the paper, we obtain a new method to implement AVL tree; if a mid node is used as new tree root ,the smaller one is used as a child tree,the larger one is used asa right child tree.

To assign a disorderly sequence to construct the AVL tree,the traditional method starts from the empty tree to insert the point in turn.

Incremental rule-extraction algorithm based on variable precision rough set and search tree;

A Routing Lookup Algorithm Based on Fast Search Trees;

The proposed algorithm raises the efficiency of ergodic search trees and speeds up pruning.

For conventional Gaussian approximation(GA) detection,tree-search method is used and only part of transmit symbol combinations contributing significantly to posterior probabilities are retained,having a complexity linear with retained branches number.

The Ant-Q algorithm can effectively implement this kind of tree search,and then the optimal solution of the rectangular part optimal layout will be obtained.

To implement this kind of tree search using ant colony system algorithm, a number of artifical ants are distributed on the root of the AND/OR tree and communicate with one another through the phenomenon trails.

To im-plement this kind of tree search using ant colony system algorithm,a number of artificial ants are distributed on the root of the AND/OR tree and communicate with one another through the pheromone trails which are a form of the long-term memory guiding the futu.