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: "a design tool to reason about ambient assisted living systems"
  Abstract: This paper proposes a design tool to investigate the properties and emergent behaviours of a special class of Ambient Assisted Living systems, namely mutual assistance communities where the dwellers contribute to each other's well being. Purpose of our system is to understand how mutual assistance communities work, what consequences a design decision could ultimately bring about, and how to construct care communities providing timely and cost-effective service for elderly and disabled people. We prove that mutual assistance between dwellers can provide care in time, and decrease the requirement for professional medical service. The simulation results show that with the existing rules most of the requirements for help can be solved or promptly initiated inside the community before their members resort to external professionals.

Connected through hyperedge HE-1 (induced by source paper "promises and challenges of ambient assisted living systems"):
  with members:
    - "a service oriented infrastructure approach for mutual assistance communities"
    - "participant a new concept for optimally assisting the elder people"

Connected through hyperedge HE-2 (induced by source paper "service oriented communities visions and contributions towards social organizations"):
  with members:
    - "on the requirements of new software development"
    - "promises and challenges of ambient assisted living systems"
    - "a service oriented infrastructure approach for mutual assistance communities"
    - "the missing ones key ingredients towards effective ambient assisted living systems"
    - "participant a new concept for optimally assisting the elder people"

Connected through hyperedge HE-3 (induced by source paper "the missing ones key ingredients towards effective ambient assisted living systems"):
  with members:
    - "promises and challenges of ambient assisted living systems"
    - "a service oriented infrastructure approach for mutual assistance communities"
    - "participant a new concept for optimally assisting the elder people"

Connected through hyperedge HE-4 (induced by source paper "on the constituent attributes of software and organizational resilience"):
  with members:
    - "on the requirements of new software development"
    - "a survey of linguistic structures for application level fault tolerance"
    - "service oriented communities visions and contributions towards social organizations"
    - "the missing ones key ingredients towards effective ambient assisted living systems"
    - "participant a new concept for optimally assisting the elder people"

Connected through hyperedge HE-5 (induced by source paper "participant a new concept for optimally assisting the elder people"):
  with members:
    - "a service oriented infrastructure approach for mutual assistance communities"

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.CY(Computers and Society)