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: "millimeter wave power transfer and information transmission"
  Abstract: Compared to the existing lower frequency wireless power transfer, millimeter wave (mmWave) power transfer takes advantage of the high-dimensional multi-antenna and narrow beam transmission. In this paper we introduce wireless power transfer for mmWave cellular networks. Here, we consider users with large energy storage that are recharged by the mmWave base stations prior to uplink information transmission, and analyze the average harvested energy and average achievable rate. Numerical results corroborate our analysis and show that the serving base station plays a dominant role in wireless power transfer, and the contribution of the interference power from the interfering base stations is negligible, even when the interfering base stations are dense. By examining the average achievable rate in the uplink, when increasing the base station density, a transition from a noise-limited regime to an interference-limited regime is observed.

Connected through hyperedge HE-1 (induced by source paper "wireless powered dense cellular networks how many small cells do we need"):
  with members:
    - "user association in 5g networks a survey and an outlook"
    - "tractable resource management with uplink decoupled millimeter wave overlay in ultra dense cellular networks"
    - "wireless power transfer in massive mimo aided hetnets with user association"
    - "millimeter wave energy harvesting"
    - "performance analysis of ambient rf energy harvesting with repulsive point process modeling"
    - "deploying dense networks for maximal energy efficiency small cells meet massive mimo"
    - "5g ultra dense cellular networks"
    - "throughput optimization for massive mimo systems powered by wireless energy transfer"

Connected through hyperedge HE-2 (induced by source paper "power beacon assisted millimeter wave ad hoc networks"):
  with members:
    - "modeling and analyzing millimeter wave cellular systems"
    - "adaptively directional wireless power transfer for large scale sensor networks"
    - "performance analysis of outdoor mmwave ad hoc networks"
    - "device to device millimeter wave communications interference coverage rate and finite topologies"
    - "the intensity matching approach a tractable stochastic geometry approximation to system level analysis of cellular networks"
    - "communications and signals design for wireless power transmission"
    - "ambient rf energy harvesting in ultra dense small cell networks performance and trade offs"
    - "millimeter wave energy harvesting"

Connected through hyperedge HE-3 (induced by source paper "wireless power transfer in massive mimo aided hetnets with user association"):
  with members:
    - "user association in massive mimo hetnets"
    - "user association in 5g networks a survey and an outlook"
    - "joint downlink cell association and bandwidth allocation for wireless backhauling in two tier hetnets with large scale antenna arrays"
    - "millimeter wave energy harvesting"
    - "performance analysis of simultaneous wireless information and power transfer with ambient rf energy harvesting"
    - "why to decouple the uplink and downlink in cellular networks and how to do it"
    - "5g cellular key enabling technologies and research challenges"
    - "throughput optimization for massive mimo systems powered by wireless energy transfer"

Connected through hyperedge HE-4 (induced by source paper "power availability aware cell association for energy harvesting small cell base stations"):
  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"
    - "distributed multi relay selection in accumulate then forward energy harvesting relay networks"
    - "user association in 5g networks a survey and an outlook"
    - "online ski rental for on off scheduling of energy harvesting base stations"
    - "a survey of energy efficient techniques for 5g networks and challenges ahead"
    - "ambient rf energy harvesting in ultra dense small cell networks performance and trade offs"
    - "millimeter wave energy harvesting"

Connected through hyperedge HE-5 (induced by source paper "on the feasibility of wireless energy transfer using massive antenna arrays"):
  with members:
    - "energy harvesting wireless communications a review of recent advances"
    - "throughput optimization for massive mimo systems powered by wireless energy transfer"
    - "enhancing wireless information and power transfer by exploiting multi antenna techniques"
    - "optimized training for net energy maximization in multi antenna wireless energy transfer over frequency selective channel"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "full duplex wireless powered relay with self energy recycling"
    - "massive mimo for next generation wireless systems"
    - "optimized training design for wireless energy transfer"

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)