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: "secure swipt networks based on a non linear energy harvesting model"
  Abstract: We optimize resource allocation to enable communication security in simultaneous wireless information and power transfer (SWIPT) for internet-of-things (IoT) networks. The resource allocation algorithm design is formulated as a non-convex optimization problem. We aim at maximizing the total harvested power at energy harvesting (EH) receivers via the joint optimization of transmit beamforming vectors and the covariance matrix of the artificial noise injected to facilitate secrecy provisioning. The proposed problem formulation takes into account the non-linearity of energy harvesting circuits and the quality of service requirements for secure communication. #R##N#To obtain a globally optimal solution of the resource allocation problem, we first transform the resulting non-convex sum-of-ratios objective function into an equivalent objective function in parametric subtractive form, which facilitates the design of a novel iterative resource allocation algorithm. In each iteration, the semidefinite programming (SDP) relaxation approach is adopted to solve a rank-constrained optimization problem optimally. Numerical results reveal that the proposed algorithm can guarantee communication security and provide a significant performance gain in terms of the harvested energy compared to existing designs which are based on the traditional linear EH model.

Connected through hyperedge HE-1 (induced by source paper "sensitive and nonlinear far field rf energy harvesting in wireless communications"):
  with members:
    - "waveform design for wireless power transfer with limited feedback"
    - "lora backscatter enabling the vision of ubiquitous connectivity"
    - "large scale multiantenna multisine wireless power transfer"
    - "max min fair beamforming for swipt systems with non linear eh model"
    - "wireless information and power transfer over an awgn channel nonlinearity and asymmetric gaussian signaling"
    - "prototyping and experimentation of a closed loop wireless power transmission with channel acquisition and waveform optimization"
    - "low complexity adaptive multisine waveform design for wireless power transfer"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"

Connected through hyperedge HE-2 (induced by source paper "dynamic power splitting for swipt with nonlinear energy harvesting in ergodic fading channel"):
  with members:
    - "fundamentals of wireless information and power transfer from rf energy harvester models to signal and system designs"
    - "joint tx power allocation and rx power splitting for swipt system with multiple nonlinear energy harvesting circuits"
    - "wirelessly powered backscatter communications waveform design and snr energy tradeoff"
    - "wireless information and power transfer over an awgn channel nonlinearity and asymmetric gaussian signaling"
    - "waveform design for wireless power transfer"
    - "wireless information and power transfer nonlinearity waveform design and rate energy tradeoff"
    - "secrecy wireless information and power transfer in fading wiretap channel"
    - "communications and signals design for wireless power transmission"

Connected through hyperedge HE-3 (induced by source paper "hybrid precoding based millimeter wave massive mimo noma with simultaneous wireless information and power transfer"):
  with members:
    - "machine learning inspired energy efficient hybrid precoding for mmwave massive mimo systems"
    - "energy efficient power allocation in millimeter wave massive mimo with non orthogonal multiple access"
    - "joint beamforming and power splitting control in downlink cooperative swipt noma systems"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "limited feedback hybrid precoding for multi user millimeter wave systems"
    - "a general mimo framework for noma downlink and uplink transmission based on signal alignment"
    - "simultaneous wireless information and power transfer in modern communication systems"
    - "joint transmit beamforming and receive power splitting for miso swipt systems"

Connected through hyperedge HE-4 (induced by source paper "enhancing phy security of miso noma swipt systems with a practical non linear eh model"):
  with members:
    - "joint pilot and payload power control for uplink mimo noma with mrc sic receivers"
    - "optimal resource allocation for power efficient mc noma with imperfect channel state information"
    - "spectrum and energy efficient beamspace mimo noma for millimeter wave communications using lens antenna array"
    - "joint beamforming and power splitting control in downlink cooperative swipt noma systems"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "secrecy sum rate maximization in non orthogonal multiple access"
    - "robust an aided beamforming and power splitting design for secure miso cognitive radio with swipt"
    - "energy efficient transmission design in non orthogonal multiple access"

Connected through hyperedge HE-5 (induced by source paper "resource allocation for secure miso noma cognitive radios relying on swipt"):
  with members:
    - "energy efficient noma enabled heterogeneous cloud radio access networks"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "nonorthogonal multiple access in large scale underlay cognitive radio networks"
    - "secrecy sum rate maximization in non orthogonal multiple access"
    - "robust an aided beamforming and power splitting design for secure miso cognitive radio with swipt"
    - "on the design of secure non orthogonal multiple access systems"
    - "wireless networks with rf energy harvesting a contemporary survey"

Connected through hyperedge HE-6 (induced by source paper "max min fair beamforming for swipt systems with non linear eh model"):
  with members:
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "practical non linear energy harvesting model and resource allocation for swipt systems"
    - "enhancing wireless information and power transfer by exploiting multi antenna techniques"
    - "robust beamforming for secure communication in systems with wireless information and power transfer"
    - "secure and green swipt in distributed antenna networks with limited backhaul capacity"
    - "max min fair wireless energy transfer for secure multiuser communication systems"
    - "secrecy wireless information and power transfer with miso beamforming"
    - "application of smart antenna technologies in 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)