human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "mammogrid a service oriented architecture based medical grid application"
  Abstract: The MammoGrid project has recently delivered its first proof-of-concept prototype using a Service-Oriented Architecture (SOA)-based Grid application to enable distributed computing spanning national borders. The underlying AliEn Grid infrastructure has been selected because of its practicality and because of its emergence as a potential open source standards-based solution for managing and coordinating distributed resources. The resultant prototype is expected to harness the use of huge amounts of medical image data to perform epidemiological studies, advanced image processing, radiographic education and ultimately, tele-diagnosis over communities of medical virtual organisations. The MammoGrid prototype comprises a high-quality clinician visualization workstation used for data acquisition and inspection, a DICOM-compliant interface to a set of medical services (annotation, security, image analysis, data storage and querying services) residing on a so-called Grid-box and secure access to a network of other Grid-boxes connected through Grid middleware. This paper outlines the MammoGrid approach in managing a federation of Grid-connected mammography databases in the context of the recently delivered prototype and will also describe the next phase of prototyping.

Connected through hyperedge HE-1 (induced by source paper "providing traceability for neuroimaging analyses"):
  with members:
    - "an integrated e science analysis base for computation neuroscience experiments and analysis"
    - "reusable services from the neugrid project for grid based health applications"
    - "research traceability using provenance services for biomedical analysis"
    - "cloud computing and grid computing 360 degree compared"
    - "experiences of engineering grid based medical software"
    - "pattern reification as the basis for description driven systems"
    - "the anatomy of the grid enabling scalable virtual organizations"

Connected through hyperedge HE-2 (induced by source paper "deployment of a grid based medical imaging application"):
  with members:
    - "a use case driven approach in requirements engineering the mammogrid project"
    - "grid databases for shared image analysis in the mammogrid project"
    - "the alien system status and perspectives"

Question: Please tell me which class the center node belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.DC(Distributed, Parallel, and Cluster Computing)