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: "mobile cloud forensics an analysis of seven popular android apps"
  Abstract: Using the evidence collection and analysis methodology for Android devices proposed by Martini, Do and Choo, we examined and analyzed seven popular Android cloud-based apps. Firstly, we analyzed each app in order to see what information could be obtained from their private app storage and SD card directories. We collated the information and used it to aid our investigation of each app database files and AccountManager data. To complete our understanding of the forensic artefacts stored by apps we analyzed, we performed further analysis on the apps to determine if the user authentication credentials could be collected for each app based on the information gained in the initial analysis stages. The contributions of this research include a detailed description of artefacts, which are of general forensic interest, for each app analyzed.

Connected through hyperedge HE-1 (induced by source paper "ubuntu one investigation detecting evidences on client machines"):
  with members:
    - "digital forensic investigation of cloud storage services"
    - "conceptual evidence collection and analysis methodology for android devices"
    - "calm before the storm the challenges of cloud computing in digital forensics"

Connected through hyperedge HE-2 (induced by source paper "forensics analysis of android mobile voip apps"):
  with members:
    - "windows instant messaging app forensics facebook and skype as case studies"
    - "on the feasibility of attribute based encryption on smartphone devices"
    - "a forensically sound adversary model for mobile devices"
    - "forensic taxonomy of popular android mhealth apps"
    - "conceptual evidence collection and analysis methodology for android devices"
    - "privacy risks in mobile dating apps"
    - "forensic analysis of whatsapp messenger on android smartphones"
    - "can t you hear me knocking identification of user actions on android apps via traffic analysis"

Connected through hyperedge HE-3 (induced by source paper "forensic investigation of p2p cloud storage bittorrent sync as a case study"):
  with members:
    - "ubuntu one investigation detecting evidences on client machines"
    - "digital forensic investigation of cloud storage services"
    - "windows instant messaging app forensics facebook and skype as case studies"
    - "network investigation methodology for bittorrent sync"
    - "leveraging decentralization to extend the digital evidence acquisition window case study on bittorrent sync"
    - "bittorrent sync first impressions and digital forensic implications"
    - "bittorrent sync network investigation methodology"
    - "seclaas secure logging as a service for cloud forensics"

Connected through hyperedge HE-4 (induced by source paper "investigating storage as a service cloud platform pcloud as a case study"):
  with members:
    - "ubuntu one investigation detecting evidences on client machines"
    - "digital forensic investigation of cloud storage services"
    - "cloud storage forensic hubic as a case study"
    - "bittorrent sync first impressions and digital forensic implications"
    - "using smartphones as a proxy for forensic evidence contained in cloud storage services"

Connected through hyperedge HE-5 (induced by source paper "cloud storage forensics analysis of data remnants on spideroak justcloud and pcloud"):
  with members:
    - "ubuntu one investigation detecting evidences on client machines"
    - "digital forensic investigation of cloud storage services"
    - "cloud storage forensic hubic as a case study"
    - "using smartphones as a proxy for forensic evidence contained in cloud storage services"

Connected through hyperedge HE-6 (induced by source paper "an android cloud storage apps forensic taxonomy"):
  with members:
    - "ubuntu one investigation detecting evidences on client machines"
    - "windows instant messaging app forensics facebook and skype as case studies"
    - "forensic taxonomy of popular android mhealth apps"
    - "conceptual evidence collection and analysis methodology for android devices"

Connected through hyperedge HE-7 (induced by source paper "conceptual evidence collection and analysis methodology for android devices"):
  with members:
    - "digital forensic investigation of cloud storage services"
    - "droidanalytics a signature based analytic system to collect extract analyze and associate android malware"

Connected through hyperedge HE-8 (induced by source paper "a forensically sound adversary model for mobile devices"):
  with members:
    - "conceptual evidence collection and analysis methodology for android devices"

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)