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: "on the efficiency of far field wireless power transfer"
  Abstract: Far-field wireless power transfer (WPT) is a promising technique to resolve the painstaking power-charging problem inherent in various wireless terminals. This paper investigates the power transfer efficiency of the WPT segment in future communication systems in support of simultaneous power and data transfer, by means of analytically computing the time-average output direct current (DC) power at user equipments (UEs). In order to investigate the effect of channel variety among UEs on the average output DC power, different policies for the scheduling of the power transfer among the users are implemented and compared in two scenarios: homogeneous, whereby users are symmetric and experience similar path loss, and heterogeneous, whereby users are asymmetric and exhibit different path losses. Specifically, if opportunistic scheduling is performed among   $N$    symmetric/asymmetric UEs, the power scaling laws are attained by using extreme value theory and reveal that the gain in power transfer efficiency is   $\ln{N}$    if UEs are symmetric whereas the gain is   $N$   if UEs are asymmetric, compared with that of conventional round-robin scheduling. Thus, the channel variety among UEs inherent to the wireless environment can be exploited by opportunistic scheduling to significantly improve the power transfer efficiency when designing future wireless communication systems in support of simultaneous power and data transfer.

Connected through hyperedge HE-1 (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"
    - "distributed wireless power transfer with energy feedback"
    - "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"

Connected through hyperedge HE-2 (induced by source paper "joint communication and computation optimization for wireless powered mobile edge computing with d2d offloading"):
  with members:
    - "joint task assignment and resource allocation for d2d enabled mobile edge computing"
    - "joint computation and communication cooperation for energy efficient mobile edge computing"
    - "wireless powered user cooperative computation in mobile edge computing systems"
    - "throughput maximization for uav enabled wireless powered communication networks"
    - "waveform design for wireless power transfer with limited feedback"
    - "exploiting massive d2d collaboration for energy efficient mobile edge computing"
    - "a survey on mobile edge computing the communication perspective"
    - "uav enabled wireless power transfer trajectory design and energy optimization"

Connected through hyperedge HE-3 (induced by source paper "opportunistic wireless energy beamforming using rssi feedback"):
  with members:
    - "wireless energy transfer to a pair of energy receivers using signal strength feedback"
    - "wireless energy beamforming using received signal strength indicator feedback"
    - "over the air implementation of uplink noma"
    - "optimized training for net energy maximization in multi antenna wireless energy transfer over frequency selective channel"
    - "energy beamforming with one bit feedback"
    - "throughput maximization in wireless powered communication networks"
    - "spatially selective artificial noise aided transmit optimization for miso multi eves secrecy rate maximization"
    - "a novel mode switching scheme utilizing random beamforming for opportunistic energy harvesting"

Connected through hyperedge HE-4 (induced by source paper "joint communication and motion energy minimization in ugv backscatter communication"):
  with members:
    - "joint trajectory and communication design for multi uav enabled wireless networks"
    - "inference from randomized transmissions by many backscatter sensors"
    - "multistatic scatter radio sensor networks for extended coverage"
    - "multipair two way relay network with harvest then transmit users resolving pairwise uplink downlink coupling"
    - "internet of things iot a vision architectural elements and future directions"

Connected through hyperedge HE-5 (induced by source paper "optimization of power transfer efficiency and energy efficiency for wireless powered systems with massive mimo"):
  with members:
    - "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"
    - "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"
    - "energy harvesting wireless communications a review of recent advances"
    - "powering the next billion devices with wi fi"
    - "is massive mimo energy efficient"

Connected through hyperedge HE-6 (induced by source paper "rf based energy harvesting in decode and forward relaying systems ergodic and outage capacities"):
  with members:
    - "smart charging for electric vehicles a survey from the algorithmic perspective"
    - "distributed hybrid power state estimation under pmu sampling phase errors"
    - "distributed clock skew and offset estimation in wireless sensor networks asynchronous algorithm and convergence analysis"
    - "distributed power splitting for swipt in relay interference channels using game theory"
    - "power allocation strategies in energy harvesting wireless cooperative networks"
    - "relaying protocols for wireless energy harvesting and information processing"
    - "wireless information transfer with opportunistic energy harvesting"
    - "wireless information and power transfer architecture design and rate energy tradeoff"

Connected through hyperedge HE-7 (induced by source paper "on the beneficial roles of fading and transmit diversity in wireless power transfer with nonlinear energy harvesting"):
  with members:
    - "fundamentals of wireless information and power transfer from rf energy harvester models to signal and system designs"
    - "sensitive and nonlinear far field rf energy harvesting in wireless communications"
    - "waveform design for wireless power transfer with limited feedback"
    - "large scale multiantenna multisine wireless power transfer"
    - "on capacity achieving distributions over complex awgn channels under nonlinear power constraints and their applications to swipt"
    - "wireless information and power transfer over an awgn channel nonlinearity and asymmetric gaussian signaling"
    - "low complexity adaptive multisine waveform design for wireless power transfer"
    - "waveform optimization for radio frequency wireless power transfer"

Connected through hyperedge HE-8 (induced by source paper "cluster based wireless energy transfer for low complex energy receivers"):
  with members:
    - "wireless energy transfer to a pair of energy receivers using signal strength feedback"
    - "wireless energy beamforming using received signal strength indicator feedback"
    - "waveform design for wireless power transfer with limited feedback"
    - "over the air implementation of uplink noma"
    - "optimized training for net energy maximization in multi antenna wireless energy transfer over frequency selective channel"
    - "energy beamforming with one bit feedback"
    - "throughput maximization in wireless powered communication networks"
    - "spatially selective artificial noise aided transmit optimization for miso multi eves secrecy rate maximization"

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)