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: "artificial noise aided secrecy information and power transfer in ofdma systems"
  Abstract: In this paper, we study simultaneous wireless information and power transfer (SWIPT) in orthogonal frequency division multiple access (OFDMA) systems with the coexistence of information receivers (IRs) and energy receivers (ERs). The IRs are served with best-effort secrecy data and the ERs harvest energy with minimum required harvested power. To enhance the physical layer security for IRs and yet satisfy energy harvesting requirements for ERs, we propose a new frequency-domain artificial noise (AN) aided transmission strategy. With the new strategy, we study the optimal resource allocation for the weighted sum secrecy rate maximization for IRs by power and subcarrier allocation at the transmitter. The studied problem is shown to be a mixed integer programming problem and thus nonconvex, while we propose an efficient algorithm for solving it based on the Lagrange duality method. To further reduce the computational complexity, we also propose a suboptimal algorithm of lower complexity. The simulation results illustrate the effectiveness of proposed algorithms as compared against other heuristic schemes.

Connected through hyperedge HE-1 (induced by source paper "energy efficiency of distributed antenna systems with wireless power transfer"):
  with members:
    - "energy efficient swipt in iot distributed antenna systems"
    - "wirelessly powered backscatter communications waveform design and snr energy tradeoff"
    - "fundamental green tradeoffs progresses challenges and impacts on 5g networks"
    - "power allocation for secure swipt systems with wireless powered cooperative jamming"
    - "wireless information and power transfer nonlinearity waveform design and rate energy tradeoff"
    - "information and energy cooperation in ofdm relaying protocols and optimization"
    - "secure and green swipt in distributed antenna networks with limited backhaul capacity"
    - "optimal resource allocation in full duplex wireless powered communication network"

Connected through hyperedge HE-2 (induced by source paper "charge then forward wireless powered communication for multiuser relay networks"):
  with members:
    - "joint power allocation and beamforming for energy efficient two way multi relay communications"
    - "power allocation for secure swipt systems with wireless powered cooperative jamming"
    - "capacity of the two hop relay channel with wireless energy transfer from relay to source and energy transmission cost"
    - "multipair two way relay network with harvest then transmit users resolving pairwise uplink downlink coupling"
    - "wireless powered communication opportunities and challenges"
    - "wireless powered relays in cooperative communications time switching relaying protocols and throughput analysis"
    - "harvest then cooperate wireless powered cooperative communications"
    - "wireless powered cooperative communications via a hybrid relay"

Connected through hyperedge HE-3 (induced by source paper "on the secrecy capacity of a full duplex wirelessly powered communication system"):
  with members:
    - "exploiting interference for secrecy wireless information and power transfer"
    - "capacity of a full duplex wirelessly powered communication system with self interference and processing cost"
    - "power allocation for secure swipt systems with wireless powered cooperative jamming"
    - "physical layer security in heterogeneous networks with jammer selection and full duplex users"
    - "mimo wiretap channel under receiver side power constraints with applications to wireless power transfer and cognitive radio"
    - "wireless powered communication networks an overview"
    - "accumulate and jam towards secure communication via a wireless powered full duplex jammer"
    - "capacity of the gaussian two hop full duplex relay channel with residual self interference"

Connected through hyperedge HE-4 (induced by source paper "on the secrecy performance of swipt receiver architectures with multiple eavesdroppers"):
  with members:
    - "secrecy outage for wireless sensor networks"
    - "secrecy outage of swipt in the presence of cooperating eavesdroppers"
    - "secure communications with cooperative jamming optimal power allocation and secrecy outage analysis"
    - "physical layer security jamming theoretical limits and practical designs in wireless networks"
    - "secrecy wireless information and power transfer challenges and opportunities"
    - "simultaneous wireless information and power transfer in modern communication systems"
    - "opportunistic wireless energy harvesting in cognitive radio networks"
    - "simultaneous information and power transfer for broadband wireless systems"

Connected through hyperedge HE-5 (induced by source paper "energy efficient swipt in iot distributed antenna systems"):
  with members:
    - "simultaneous wireless information and power transfer in cooperative relay networks with rateless codes"
    - "training based swipt optimal power splitting at the receiver"
    - "energy efficient resource assignment and power allocation in heterogeneous cloud radio access networks"
    - "information and energy cooperation in ofdm relaying protocols and optimization"
    - "energy harvesting for physical layer security in ofdma networks"
    - "wireless information and energy transfer for two hop non regenerative mimo ofdm relay networks"
    - "secure and green swipt in distributed antenna networks with limited backhaul capacity"
    - "energy beamforming with one bit feedback"

Connected through hyperedge HE-6 (induced by source paper "optimal fairness aware time and power allocation in wireless powered communication networks"):
  with members:
    - "wireless networks with energy harvesting and power transfer joint power and time allocation"
    - "adaptively directional wireless power transfer for large scale sensor networks"
    - "wireless powered communication networks an overview"
    - "wireless powered communication opportunities and challenges"
    - "energy harvesting for physical layer security in ofdma networks"
    - "simultaneous wireless information and power transfer in modern communication systems"
    - "throughput maximization in wireless powered communication networks"
    - "asymptotically optimal power allocation for energy harvesting communication networks"

Connected through hyperedge HE-7 (induced by source paper "coexistence of rf powered iot and a primary wireless network with secrecy guard zones"):
  with members:
    - "power allocation for secure swipt systems with wireless powered cooperative jamming"
    - "secrecy outage analysis for downlink transmissions in the presence of randomly located eavesdroppers"
    - "modeling and analysis of cellular networks using stochastic geometry a tutorial"
    - "tight lower bounds on the contact distance distribution in poisson hole process"
    - "stochastic geometry based comparison of secrecy enhancement techniques in d2d networks"
    - "a primer on cellular network analysis using stochastic geometry"
    - "spatio temporal interference correlation and joint coverage in cellular networks"
    - "mimo wiretap channel under receiver side power constraints with applications to wireless power transfer and cognitive radio"

Connected through hyperedge HE-8 (induced by source paper "physical layer security in heterogeneous networks with jammer selection and full duplex users"):
  with members:
    - "exploiting full duplex receivers for achieving secret communications in multiuser miso networks"
    - "power allocation for secure swipt systems with wireless powered cooperative jamming"
    - "hybrid duplex switching in heterogeneous networks"
    - "opportunistic jamming for enhancing security stochastic geometry modeling and analysis"
    - "physical layer security in millimeter wave cellular networks"
    - "a survey on wireless security technical challenges recent advances and future trends"
    - "physical layer security in heterogeneous cellular networks"
    - "secure communication in uplink transmissions user selection and multiuser secrecy gain"

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)