Based on the analysis of famous distributed systems and ASAAC standards,the transparency of distributed systems is mainly reflected in eight aspects which are access transparency,location transparency,concurrency transparency,replication transparency,failure transparency,migration transparency,performance transparency and scaling transparency.

The architecture provides convenient data classification,completed policy management,au-tomatic data migration and transparent access to the migrated data to clients and application.

For that reason,Web services has become the basic means of transparent accessing network database.

In view of the current problems of high -speed milling database, such as a wide range of heterogeneous databases, the different structure, data duplication and so on, Heterogeneous database sharing strategy with the transparent access and the data conversion is proposed based on the analysis of a typical structure and characteristics of the high-speed milling database.

The simulation modeling method by Task/Resource Graph is very advantageous to analyzing complicated discrete real-time systems due to its abundant time attributes, correspondingly, effect on schedulability by its tasks schedule algorithms and resource access control protocols will be very complicated.

At first, the Task/Resource Graph modeling method is briefly reviewed, and then task real-time schedule algorithms and resource access control protocols are addressed principally.

Context-aware resource access control in scientific workflows;