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: "intercept probability analysis of cooperative wireless networks with best relay selection in the presence of eavesdropping attack"
  Abstract: Due to the broadcast nature of wireless medium, wireless communication is extremely vulnerable to eavesdropping attack. Physical-layer security is emerging as a new paradigm to prevent the eavesdropper from interception by exploiting the physical characteristics of wireless channels, which has recently attracted a lot of research attentions. In this paper, we consider the physical-layer security in cooperative wireless networks with multiple decode-and-forward (DF) relays and investigate the best relay selection in the presence of eavesdropping attack. For the comparison purpose, we also examine the conventional direct transmission without relay and traditional max-min relay selection. We derive closed-form intercept probability expressions of the direct transmission, traditional max-min relay selection, and proposed best relay selection schemes in Rayleigh fading channels. Numerical results show that the proposed best relay selection scheme strictly outperforms the traditional direct transmission and max-min relay selection schemes in terms of intercept probability. In addition, as the number of relays increases, the intercept probabilities of both traditional max-min relay selection and proposed best relay selection schemes decrease significantly, showing the advantage of exploiting multiple relays against eavesdropping attack.

Connected through hyperedge HE-1 (induced by source paper "on the security analysis of a cooperative incremental relaying protocol in the presence of an active eavesdropper"):
  with members:
    - "power allocation and cooperative diversity in two way non regenerative cognitive radio networks"
    - "security versus reliability analysis of opportunistic relaying"
    - "opportunistic secrecy with a strict delay constraint"
    - "on the design of artificial noise aided secure multi antenna transmission in slow fading channels"
    - "three receiver broadcast channels with side information"
    - "a secure communication game with a relay helping the eavesdropper"
    - "joint relay and jammer selection for secure two way relay networks"
    - "buffers improve the performance of relay selection"

Connected through hyperedge HE-2 (induced by source paper "a survey on wireless security technical challenges recent advances and future trends"):
  with members:
    - "relay selection for wireless communications against eavesdropping a security reliability trade off perspective"
    - "improving physical layer security in wireless communications using diversity techniques"
    - "securing physical layer communications for cognitive radio networks"
    - "secrecy outage and diversity analysis of cognitive radio systems"
    - "security versus reliability analysis of opportunistic relaying"
    - "what will 5g be"
    - "optimal relay selection for physical layer security in cooperative wireless networks"
    - "physical layer security with multiuser scheduling in cognitive radio networks"

Connected through hyperedge HE-3 (induced by source paper "physical layer security with multiuser scheduling in cognitive radio networks"):
  with members:
    - "optimal relay selection for physical layer security in cooperative wireless networks"
    - "robust beamforming for security in mimo wiretap channels with imperfect csi"
    - "secure transmission with artificial noise over fading channels achievable rate and optimal power allocation"
    - "exploiting multi antennas for opportunistic spectrum sharing in cognitive radio networks"
    - "the secrecy capacity of the mimo wiretap channel"

Connected through hyperedge HE-4 (induced by source paper "optimal relay selection for physical layer security in cooperative wireless networks"):
  with members:
    - "joint relay and jammer selection for secure two way relay networks"
    - "cooperative jamming for secure communications in mimo relay networks"
    - "a simple cooperative diversity method based on network path selection"

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.IT(Information Theory)