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: "citizengrid an online middleware for crowdsourcing scientific research"
  Abstract: In the last few years, contributions of the general public in scientific projects has increased due to the advancement of communication and computing technologies. Internet played an important role in connecting scientists and volunteers who are interested in participating in their scientific projects. However, despite potential benefits, only a limited number of crowdsourcing based large-scale science (citizen science) projects have been deployed due to the complexity involved in setting them up and running them. In this paper, we present CitizenGrid - an online middleware platform which addresses security and deployment complexity issues by making use of cloud computing and virtualisation technologies. CitizenGrid incentivises scientists to make their small-to-medium scale applications available as citizen science projects by: 1) providing a directory of projects through a web-based portal that makes applications easy to discover; 2) providing flexibility to participate in, monitor, and control multiple citizen science projects from a common interface; 3) supporting diverse categories of citizen science projects. The paper describes the design, development and evaluation of CitizenGrid and its use cases.

Connected through hyperedge HE-1 (induced by source paper "a collaborative citizen science platform for real time volunteer computing and games"):
  with members:
    - "conceptual frameworks for building online citizen science projects"
    - "design guidelines for the user centred collaborative citizen science platforms"

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)