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: "rf energy harvesting enabled power sharing in relay networks"
  Abstract: Through simultaneous energy and information transfer, radio frequency (RF) energy harvesting (EH) reduces the energy consumption of the wireless networks. It also provides a new approach for the wireless devices to share each other's energy storage, without relying on the power grid or traffic offloading. In this paper, we study RF energy harvesting enabled power balancing within the decode-and-forward (DF) relaying-enhanced cooperative wireless system. An optimal power allocation policy is proposed for the scenario where both source and relay nodes can draw power from the radio frequency signals transmitted by each other. To maximize the overall throughput while meeting the energy constraints imposed by the RF sources, an optimization problem is formulated and solved. Based on different harvesting efficiency and channel condition, closed form solutions for optimal joint source and relay power allocation are derived.

Connected through hyperedge HE-1 (induced by source paper "on green energy powered cognitive radio networks"):
  with members:
    - "optimal cooperative power allocation for energy harvesting enabled relay networks"
    - "a traffic load balancing framework for software defined radio access networks powered by hybrid energy sources"
    - "network utility aware traffic loading balancing in backhaul constrained cache enabled small cell networks with hybrid power supplies"
    - "joint spectrum and power allocation for multi node cooperative wireless systems"
    - "throughput maximization for the gaussian relay channel with energy harvesting constraints"
    - "a learning theoretic approach to energy harvesting communication system optimization"
    - "relaying protocols for wireless energy harvesting and information processing"
    - "wideband spectrum sensing for cognitive radio networks a survey"

Connected through hyperedge HE-2 (induced by source paper "optimal cooperative power allocation for energy harvesting enabled relay networks"):
  with members:
    - "joint spectrum and power allocation for multi node cooperative wireless systems"
    - "power allocation strategies in energy harvesting wireless cooperative networks"
    - "on green energy powered cognitive radio networks"
    - "throughput maximization for the gaussian relay channel with energy harvesting constraints"
    - "relaying protocols for wireless energy harvesting and information processing"
    - "optimal save then transmit protocol for energy harvesting wireless transmitters"
    - "optimal energy allocation for wireless communications with energy harvesting constraints"
    - "transmission with energy harvesting nodes in fading wireless channels optimal policies"

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)