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: "two way beamforming optimization for full duplex swipt systems"
  Abstract: In this paper, we investigate the problem of two-way relay beamforming optimization to maximize the achievable sum-rate of a simultaneous wireless information and power transfer (SWIPT) system with a full-duplex (FD) multiple-input multiple-output (MIMO) amplify-and-forward (AF) relay. In particular, we address the optimal joint design of the receiver power splitting (PS) ratio and the beamforming matrix at the relay node given the channel state information (CSI). Our contribution is an iterative algorithm based on difference of convex (DC) programming and one-dimensional searching to achieve the joint optimal solution. Simulation results are provided to demonstrate the effectiveness of the proposed algorithm.

Connected through hyperedge HE-1 (induced by source paper "simultaneous wireless information and power transfer in miso full duplex systems"):
  with members:
    - "joint transmit power and relay two way beamforming optimization for energy harvesting full duplex communications"
    - "wireless information and power transfer in full duplex communication systems"
    - "weighted sum transmit power minimization for full duplex system with swipt and self energy recycling"
    - "all digital self interference cancellation technique for full duplex systems"
    - "joint transmit beamforming and receive power splitting for miso swipt systems"
    - "wireless information and power transfer architecture design and rate energy tradeoff"
    - "experiment driven characterization of full duplex wireless systems"
    - "mimo broadcasting for simultaneous wireless information and power transfer"

Connected through hyperedge HE-2 (induced by source paper "secure full duplex two way relaying for swipt"):
  with members:
    - "probabilistically robust swipt for secrecy misome systems"
    - "transceiver design to maximize the weighted sum secrecy rate in full duplex swipt systems"
    - "joint transmit power and relay two way beamforming optimization for energy harvesting full duplex communications"
    - "sum secrecy rate maximization for full duplex two way relay networks using alamouti based rank two beamforming"
    - "wireless information and power transfer in full duplex communication systems"
    - "mimo broadcasting for simultaneous wireless information and power transfer"

Connected through hyperedge HE-3 (induced by source paper "joint transmit power and relay two way beamforming optimization for energy harvesting full duplex communications"):
  with members:
    - "wireless information and power transfer in full duplex communication systems"
    - "joint beamforming optimization and power control for full duplex mimo two way relay channel"
    - "wireless information and power transfer with full duplex relaying"
    - "relaying protocols for wireless energy harvesting and information processing"
    - "experiment driven characterization of full duplex wireless systems"
    - "mimo broadcasting for simultaneous wireless information and power transfer"

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)