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: "distributed wireless power transfer with energy feedback"
  Abstract: Energy beamforming (EB) is a key technique for achieving efficient radio-frequency transmission enabled wireless energy transfer (WET). By optimally designing the waveforms from multiple energy transmitters (ETs) over the wireless channels, they can be constructively combined at the energy receiver (ER) to achieve an EB gain that scales with the number of ETs. However, the optimal design of EB waveforms requires accurate channel state information (CSI) at the ETs, which is challenging to obtain practically, especially in a distributed system with ETs at separate locations. In this paper, we study practical and efficient channel training methods to achieve optimal EB in a distributed WET system. We propose two protocols with and without centralized coordination, respectively, where distributed ETs either sequentially or in parallel adapt their transmit phases based on a low-complexity energy feedback from the ER. The energy feedback only depends on the received power level at the ER, where each feedback indicates one particular transmit phase that results in the maximum harvested power over a set of previously used phases. Simulation results show that the two proposed training protocols converge very fast in practical WET systems even with a large number of distributed ETs, while the protocol with sequential ET phase adaptation is also analytically shown to converge to the optimal EB design with perfect CSI by increasing the training time. Numerical results are also provided to evaluate the performance of the proposed distributed EB and training designs as compared to other benchmark schemes.

Connected through hyperedge HE-1 (induced by source paper "wirelessly powered sensor networks power allocation for channel estimation and energy beamforming"):
  with members:
    - "cluster based wireless energy transfer for low complex energy receivers"
    - "wireless energy beamforming using received signal strength indicator feedback"
    - "on the beneficial roles of fading and transmit diversity in wireless power transfer with nonlinear energy harvesting"
    - "waveform design for wireless power transfer with limited feedback"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "on the feasibility of wireless energy transfer using massive antenna arrays"
    - "waveform design for wireless power transfer"
    - "wireless information and power transfer nonlinearity waveform design and rate energy tradeoff"

Connected through hyperedge HE-2 (induced by source paper "cognitive wireless power transfer in the presence of reactive primary communication user"):
  with members:
    - "fundamentals of wireless information and power transfer from rf energy harvester models to signal and system designs"
    - "large scale multiantenna multisine wireless power transfer"
    - "joint offloading and computing optimization in wireless powered mobile edge computing systems"
    - "waveform optimization for radio frequency wireless power transfer"
    - "waveform design for wireless power transfer"
    - "surveillance and intervention of infrastructure free mobile communications a new wireless security paradigm"
    - "a general design framework for mimo wireless energy transfer with limited feedback"
    - "wireless powered communication networks an overview"

Connected through hyperedge HE-3 (induced by source paper "efficient fair and qos aware policies for wirelessly powered communication networks"):
  with members:
    - "online policies for throughput maximization of energy constrained wireless powered communication systems"
    - "optimal and near optimal policies for wireless power transfer in energy limited and power limited scenarios"
    - "optimal hierarchical radio resource management for hetnets with flexible backhaul"
    - "theory and experiment for wireless powered sensor networks how to keep sensors alive"
    - "battery powered devices in wpcns"
    - "capacity of remotely powered communication"
    - "wireless powered communication opportunities and challenges"
    - "wireless power transfer survey and roadmap"

Connected through hyperedge HE-4 (induced by source paper "throughput optimization in fdd mu miso wireless powered communication networks"):
  with members:
    - "wireless powered communication networks tdd or fdd"
    - "maximizing ergodic throughput in wireless powered communication networks"
    - "wireless power meets energy harvesting a joint energy allocation approach in ofdm based system"
    - "on the feasibility of wireless energy transfer using massive antenna arrays"
    - "a general design framework for mimo wireless energy transfer with limited feedback"
    - "wireless powered communication networks an overview"
    - "wireless powered communication opportunities and challenges"
    - "throughput optimization for massive mimo systems powered by wireless energy transfer"

Connected through hyperedge HE-5 (induced by source paper "a new interweave cognitive radio scheme for out band energy harvesting systems"):
  with members:
    - "a tractable product channel model for line of sight scenarios"
    - "the kappa mu shadowed fading model with integer fading parameters"
    - "massive machine type communications in 5g physical and mac layer solutions"
    - "green cognitive relaying opportunistically switching between data transmission and energy harvesting"
    - "on the efficiency of far field wireless power transfer"
    - "on green energy powered cognitive radio networks"
    - "spatial throughput of mobile ad hoc networks powered by energy harvesting"
    - "throughput maximization in wireless powered communication networks"

Connected through hyperedge HE-6 (induced by source paper "joint offloading and computing optimization in wireless powered mobile edge computing systems"):
  with members:
    - "reel bf design achieving the sdp bound for downlink beamforming with arbitrary shaping constraints"
    - "delay optimal computation task scheduling for mobile edge computing systems"
    - "waveform design for wireless power transfer"
    - "energy efficient resource allocation for mobile edge computation offloading"
    - "a general design framework for mimo wireless energy transfer with limited feedback"
    - "communications and signals design for wireless power transmission"
    - "wireless powered communication opportunities and challenges"
    - "practical non linear energy harvesting model and resource allocation for swipt systems"

Connected through hyperedge HE-7 (induced by source paper "optimal energy beamforming under per antenna power constraint"):
  with members:
    - "wireless energy beamforming using received signal strength indicator feedback"
    - "retrodirective multi user wireless power transfer with massive mimo"
    - "communications and signals design for wireless power transmission"
    - "wireless powered communication opportunities and challenges"
    - "collaborative wireless energy and information transfer in interference channel"
    - "enhancing wireless information and power transfer by exploiting multi antenna techniques"
    - "multiuser mimo wireless energy transfer with coexisting opportunistic communication"
    - "energy beamforming with one bit feedback"

Connected through hyperedge HE-8 (induced by source paper "distributed user association in energy harvesting dense small cell networks a mean field multi armed bandit approach"):
  with members:
    - "distributed user association in energy harvesting small cell networks an exchange economy with uncertainty"
    - "distributed user association in energy harvesting small cell networks a probabilistic bandit model"
    - "multi armed bandits with application to 5g small cells"
    - "user association in 5g networks a survey and an outlook"
    - "optimum transmission policies for energy harvesting sensor networks powered by a mobile control center"
    - "sum rate maximizing cell association via dual connectivity"
    - "multicast aware caching for small cell networks"
    - "evolution toward 5g multi tier cellular wireless networks an interference management perspective"

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)