An uncertainty reasoning method is presented in this article. The method can be used to compute from a given set of conditional probabilities the best lower bounds and the best upper bounds of those conditional probabilities that are not explicitly provided. The computation of the best upper(lower) bound of such a conditional probability relies on solution of a linear programming problem. Some reduction techniques are proposed in this article to improve the efficiency of our uncertainty reasoning method. As illustrated in Section 4.3, for many uncertainty reasoning problems in medical diagnosis, by using our reduction techniques, the best range of a conditional probability, which is specified by a lower bound and an upper bound, can be computed in polynomial time in terms of the number of basic events involved in the reasoning.

Proposes a formal approach for translating OODB queries to equivalent relational queries. The translation is accomplished through the use of relational predicate graphs and OODB predicate graphs. One advantage of using such a graph-based approach is that we can achieve bidirectional translation between relational queries and OODB queries.>

A new hybrid algorithm is proposed for well-formed path problems including the transitive closure problem. The CPU time for computation is O(ne), and blocking technique is incorporated to reduce the disk I/O cost in disk-resident environment. The new features of the new algorithm are that only parents sets instead of descendant sets are loaded in from disk, and the computation can be parallelized efficiently. Simulation results show that our algorithm is superior to other existing algorithms in sequential computation, and that linear speedup is achieved in parallel computation.>

Proposes a solution for the construction of a relational front-end for object-oriented database systems (OODBs). Rules are provided to transform the structural part of an OODB scheme to an equivalent relational scheme to provide relational users with a relational view of the OODB scheme. A mechanism based on a relational predicate graph and an OODB predicate graph is provided to translate relational queries to OODB queries to allow relational users access to data stored in an OODB database system.>