human: Given a node-centered hypergraph: <hypergraph>, where nodes represent authors and hyperedges represent groups of authors who co-authored the same paper.

Details of the hypergraph:
Center node: "Object-Oriented Design Pattern: Access Protector."
  Abstract: Access Protector is a class behavioral design pattern which distributes the routines of the original class hierarchy to given access-protection layers. The distribution utilizes dynamic binding and automatic upcasting to guarantee that the intended object access policies are transitive while the original runtime behavior between the objects does not change.

Connected through hyperedge HE-1 (induced by source paper "Ownership types for flexible alias protection"):
  with members:
    - "The Programming Language Aspects of ThingLab, a Constraint-Oriented Simulation Laboratory"

Question: Please tell me which research area the center author belongs to. The 4 classes are: Computer science, Mathematics, Engineering, Economics, Psychology, Business. Directly output the class name.

gpt: Computer science