Showing papers by "Center for Discrete Mathematics and Theoretical Computer Science published in 2007"

Private Inference Control for Aggregate Database Queries

Abstract: We study private inference control for aggregate queries, such as those provided by statistical databases or modern database languages, to a database in a way that satisfies privacy requirements and inference control requirements. For each query, the client learns the value of the function for that query if and only if the query passes a specified in- ference control rule. The server learns nothing about the queries, and the client learns nothing other than the query output for passing queries. We present general protocols for aggregate queries with private inference control.

Improved GRASP based circuit partitioning algorithm

Abstract: An improved circuit partitioning algorithm based on the greedy randomized adaptive search procedure(GRASP) was presented to improve the circuit partitioning quality of traditional iterative improvement-based algorithms.GRASP consisted of a construction phase and a local search phase and could construct good initial partitions quickly.In the construction phase,a heuristic strategy was introduced to select clusters.A very efficient searching technique called Path-Relinking was integrated into the GRASP iterative process to build paths among local optimal solutions and effectively explore the local optimal solution space.The experimental results indicated that compared to the basic GRASP,the modified algorithm improved the solution quality in a reasonable period,and obtained better partition.The minimum cut-size reached 33.3% while the average cut-size was up to 27.4%.