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 robust artificial noise aided transmit design for miso secrecy"
  Abstract: This paper considers an artificial noise (AN) aided secrecy rate maximization (SRM) problem for a multi-input single-output (MISO) channel overheard by multiple single-antenna eavesdroppers. We assume that the transmitter has perfect knowledge about the channel to the desired user but imperfect knowledge about the channels to the eavesdroppers. Therefore, the resultant SRM problem is formulated in the way that we maximize the worst-case secrecy rate by jointly designing the signal covariance ${\bf W}$ and the AN covariance ${\bf \Sigma}$. However, such a worst-case SRM problem turns out to be hard to optimize, since it is nonconvex in ${\bf W}$ and ${\bf \Sigma}$ jointly. Moreover, it falls into the class of semi-infinite optimization problems. Through a careful reformulation, we show that the worst-case SRM problem can be handled by performing a one-dimensional line search in which a sequence of semidefinite programs (SDPs) are involved. Moreover, we also show that the optimal ${\bf W}$ admits a rank-one structure, implying that transmit beamforming is secrecy rate optimal under the considered scenario. Simulation results are provided to demonstrate the robustness and effectiveness of the proposed design compared to a non-robust AN design.

Connected through hyperedge HE-1 (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"
    - "intercept probability analysis of cooperative wireless networks with best relay selection in the presence of eavesdropping attack"
    - "optimal relay selection for physical layer security in cooperative wireless networks"

Connected through hyperedge HE-2 (induced by source paper "robust secure transmission in miso channels based on worst case optimization"):
  with members:
    - "on cooperative relaying schemes for wireless physical layer security"
    - "optimal and robust transmit designs for miso channel secrecy by semidefinite programming"
    - "cooperative jamming for secure communications in mimo relay networks"
    - "robust beamforming for security in mimo wiretap channels with imperfect csi"
    - "on ergodic secrecy capacity for gaussian miso wiretap channels"
    - "secure transmission with multiple antennas ii the mimome wiretap channel"
    - "the secrecy capacity of the mimo wiretap channel"

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)