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: "energy efficient power allocation in ofdm systems with wireless information and power transfer"
  Abstract: This paper considers an orthogonal frequency division multiplexing (OFDM) downlink point-to-point system with simultaneous wireless information and power transfer. It is assumed that the receiver is able to harvest energy from noise, interference, and the desired signals. We study the design of power allocation algorithms maximizing the energy efficiency of data transmission (bit/Joule delivered to the receiver). In particular, the algorithm design is formulated as a high-dimensional non-convex optimization problem which takes into account the circuit power consumption, the minimum required data rate, and a constraint on the minimum power delivered to the receiver. Subsequently, by exploiting the properties of nonlinear fractional programming, the considered non-convex optimization problem, whose objective function is in fractional form, is transformed into an equivalent optimization problem having an objective function in subtractive form, which enables the derivation of an efficient iterative power allocation algorithm. In each iteration, the optimal power allocation solution is derived based on dual decomposition and a one-dimensional search. Simulation results illustrate that the proposed iterative power allocation algorithm converges to the optimal solution, and unveil the trade-off between energy efficiency, system capacity, and wireless power transfer: (1) In the low transmit power regime, maximizing the system capacity may maximize the energy efficiency. (2) Wireless power transfer can enhance the energy efficiency, especially in the interference limited regime.

Connected through hyperedge HE-1 (induced by source paper "wireless powered communications with non orthogonal multiple access"):
  with members:
    - "throughput analysis and optimization of wireless powered multiple antenna full duplex relay systems"
    - "non orthogonal multiple access for visible light communications"
    - "a general mimo framework for noma downlink and uplink transmission based on signal alignment"
    - "enhancing wireless information and power transfer by exploiting multi antenna techniques"
    - "uplink non orthogonal multiple access for 5g wireless networks"
    - "simultaneous wireless information and power transfer in modern communication systems"
    - "power allocation strategies in energy harvesting wireless cooperative networks"
    - "simultaneous information and energy transfer in large scale networks with without relaying"

Connected through hyperedge HE-2 (induced by source paper "optimal design of non orthogonal multiple access with wireless power transfer"):
  with members:
    - "non orthogonal multiple access for visible light communications"
    - "enhancing wireless information and power transfer by exploiting multi antenna techniques"
    - "uplink non orthogonal multiple access for 5g wireless networks"
    - "simultaneous wireless information and power transfer in modern communication systems"
    - "power allocation strategies in energy harvesting wireless cooperative networks"
    - "wireless information and power transfer with full duplex relaying"
    - "on the performance of non orthogonal multiple access in 5g systems with randomly deployed users"
    - "throughput maximization in wireless powered communication networks"

Connected through hyperedge HE-3 (induced by source paper "wireless information and power transfer energy efficiency optimization in ofdma systems"):
  with members:
    - "energy efficient resource allocation in multiuser ofdm systems with wireless information and power transfer"
    - "wireless information transfer with opportunistic energy harvesting"
    - "wireless information and power transfer architecture design and rate energy tradeoff"
    - "framework for link level energy efficiency optimization with informed transmitter"
    - "mimo broadcasting for simultaneous wireless information and power transfer"
    - "optimal packet scheduling in an energy harvesting communication system"

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)