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: "from close the door to do not click and back security by design for older adults"
  Abstract: With the growing number of older adults who adopt mobile technology in their life, a new form of challenge faces both them, as well as the software engineering communities. This challenge is the issue of safety, not only in the context of risk older adults already face on-line, but also, due to the mobile nature of the used applications, real life safety issues raising from the use of on-line solutions. In this paper, we wish to use a case study they conducted in order to address this issue of interrelating on-line and real life threats. We describe how the observation from the case study relate to the collected body off knowledge in the relevant topic, as well as propose a set of suggestion for improving the design of applications in regards to addressing the issue of older adults safety.

Connected through hyperedge HE-1 (induced by source paper "older adults and crowdsourcing android tv app for evaluating tedx subtitle quality"):
  with members:
    - "guidelines towards better participation of older adults in software development processes using a new spiral method and participatory approach"
    - "press f1 for help participatory design for dealing with on line and real life security of older adults"
    - "turned 70 it is time to start editing wikipedia"
    - "a location based game for two generations teaching mobile technology to the elderly with the support of young volunteers"
    - "beyond participatory design towards a model for teaching seniors application design"
    - "livinglab pjait towards better urban participation of seniors"
    - "emotions make cities live towards mapping emotions of older adults on urban space"

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)