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: "multi objective beamforming for secure communication in systems with wireless information and power transfer"
  Abstract: In this paper, we study power allocation for secure communication in a multiuser multiple-input single-output (MISO) downlink system with simultaneous wireless information and power transfer. The receivers are able to harvest energy from the radio frequency when they are idle. We propose a multi-objective optimization problem for power allocation algorithm design which incorporates two conflicting system objectives: total transmit power minimization and energy harvesting efficiency maximization. The proposed problem formulation takes into account a quality of service (QoS) requirement for the system secrecy capacity. Our designs advocate the dual use of artificial noise in providing secure communication and facilitating efficient energy harvesting. The multi-objective optimization problem is non-convex and is solved by a semidefinite programming (SDP) relaxation approach which results in an approximate of solution. #R##N#A sufficient condition for the global optimal solution is revealed and the accuracy of the approximation is examined. To strike a balance between computational complexity and system performance, we propose two suboptimal power allocation schemes. Numerical results not only demonstrate the excellent performance of the proposed suboptimal schemes compared to baseline schemes, but also unveil an interesting trade-off between energy harvesting efficiency and total transmit power.

Connected through hyperedge HE-1 (induced by source paper "transceiver design to maximize the weighted sum secrecy rate in full duplex swipt systems"):
  with members:
    - "on the spectral efficiency of full duplex small cell wireless systems"
    - "full duplex wireless powered relay with self energy recycling"
    - "secrecy wireless information and power transfer with miso beamforming"
    - "improving physical layer secrecy using full duplex jamming receivers"
    - "full duplex cooperative cognitive radio with transmit imperfections"
    - "resource allocation for secure communication in systems with wireless information and power transfer"
    - "coordinated beamforming for multiuser miso interference channel under rate outage constraints"
    - "self interference cancellation with phase noise induced ici suppression for full duplex systems"

Connected through hyperedge HE-2 (induced by source paper "wireless powered relays in cooperative communications time switching relaying protocols and throughput analysis"):
  with members:
    - "cutting last wires for mobile communication by microwave power transfer"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "full duplex wireless powered relay with self energy recycling"
    - "power allocation strategies in energy harvesting wireless cooperative networks"
    - "simultaneous information and energy transfer in large scale networks with without relaying"
    - "joint transmit beamforming and receive power splitting for miso swipt systems"
    - "wireless information and energy transfer in multi antenna interference channel"
    - "energy efficient resource allocation in multiuser ofdm systems with wireless information and power transfer"

Connected through hyperedge HE-3 (induced by source paper "secure beamforming for mimo broadcasting with wireless information and power transfer"):
  with members:
    - "robust beamforming for secure communication in systems with wireless information and power transfer"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "secrecy wireless information and power transfer with miso beamforming"
    - "multiuser miso beamforming for simultaneous wireless information and power transfer"
    - "joint transmit beamforming and receive power splitting for miso swipt systems"
    - "wireless information and energy transfer in multi antenna interference channel"
    - "beamforming for miso interference channels with qos and rf energy transfer"
    - "secure layered transmission in multicast systems with wireless information and power transfer"

Connected through hyperedge HE-4 (induced by source paper "robust beamforming for secure communication in systems with wireless information and power transfer"):
  with members:
    - "secrecy wireless information and power transfer with miso beamforming"
    - "multiuser miso beamforming for simultaneous wireless information and power transfer"
    - "resource allocation for secure communication in systems with wireless information and power transfer"
    - "spatially selective artificial noise aided transmit optimization for miso multi eves secrecy rate maximization"
    - "wireless information and power transfer energy efficiency optimization in ofdma systems"
    - "distributed robust multicell coordinated beamforming with imperfect csi an admm approach"
    - "wireless information and power transfer architecture design and rate energy tradeoff"
    - "robust beamforming for wireless information and power transmission"

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)