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: "placement optimization of energy and information access points in wireless powered communication networks"
  Abstract: The applications of wireless power transfer technology to wireless communications can help build a wireless powered communication network (WPCN) with more reliable and sustainable power supply compared to the conventional battery-powered network. However, due to the fundamental differences in wireless information and power transmissions, many important aspects of conventional battery-powered wireless communication networks need to be redesigned for efficient operations of WPCNs. In this paper, we study the placement optimization of energy and information access points in WPCNs, where the wireless devices (WDs) harvest the radio frequency energy transferred by dedicated energy nodes (ENs) in the downlink, and use the harvested energy to transmit data to information access points (APs) in the uplink. In particular, we are interested in minimizing the network deployment cost with minimum number of ENs and APs by optimizing their locations, while satisfying the energy harvesting and communication performance requirements of the WDs. Specifically, we first study the minimum-cost placement problem when the ENs and APs are separately located, where an alternating optimization method is proposed to jointly optimize the locations of ENs and APs. Then, we study the placement optimization when each pair of EN and AP are co-located and integrated as a hybrid access point, and propose an efficient algorithm to solve this problem. Simulation results show that the proposed methods can effectively reduce the network deployment cost and yet guarantee the given performance requirements, which is a key consideration in the future applications of WPCNs.

Connected through hyperedge HE-1 (induced by source paper "reusing wireless power transfer for backscatter assisted relaying in wpcns"):
  with members:
    - "backscatter assisted relaying in wireless powered communications network"
    - "deep reinforcement learning for online computation offloading in wireless powered mobile edge computing networks"
    - "joint tx power allocation and rx power splitting for swipt system with multiple nonlinear energy harvesting circuits"
    - "multi antenna enabled cluster based cooperation in wireless powered communication networks"
    - "distributed scheduling in wireless powered communication network protocol design and performance analysis"
    - "ambient backscatter communications a contemporary survey"
    - "user cooperation for enhanced throughput fairness in wireless powered communication networks"
    - "distributed charging control in broadband wireless power transfer networks"

Connected through hyperedge HE-2 (induced by source paper "optimizing throughput fairness of cluster based cooperation in underlay cognitive wpcns"):
  with members:
    - "throughput maximization for uav enabled wireless powered communication networks"
    - "optimization and analysis of wireless powered multi antenna cooperative systems"
    - "multi antenna enabled cluster based cooperation in wireless powered communication networks"
    - "user cooperation for enhanced throughput fairness in wireless powered communication networks"
    - "distributed charging control in broadband wireless power transfer networks"
    - "wireless powered communication networks an overview"
    - "wireless powered communication opportunities and challenges"
    - "cognitive wireless powered network spectrum sharing models and throughput maximization"

Connected through hyperedge HE-3 (induced by source paper "optimization of energy constrained wireless powered communication networks with heterogeneous nodes"):
  with members:
    - "cognitive wireless powered network spectrum sharing models and throughput maximization"
    - "user cooperation in wireless powered communication networks"
    - "optimal resource allocation in full duplex wireless powered communication network"
    - "full duplex wireless powered communication network with energy causality"
    - "throughput maximization in wireless powered communication networks"
    - "opportunistic wireless energy harvesting in cognitive radio networks"
    - "simultaneous information and power transfer for broadband wireless systems"
    - "wireless information and power transfer architecture design and rate energy tradeoff"

Connected through hyperedge HE-4 (induced by source paper "wireless power transfer with information asymmetry a public goods perspective"):
  with members:
    - "efficient network sharing with asymmetric constraint information"
    - "distributed charging control in broadband wireless power transfer networks"
    - "wireless powered communication networks an overview"
    - "communications and signals design for wireless power transmission"
    - "wireless powered communication opportunities and challenges"
    - "throughput maximization in wireless powered communication networks"
    - "simultaneous information and power transfer for broadband wireless systems"
    - "wireless information and power transfer in multiuser ofdm systems"

Connected through hyperedge HE-5 (induced by source paper "when tesla meets nash wireless power provision as a public good"):
  with members:
    - "distributed charging control in broadband wireless power transfer networks"
    - "wireless powered communication networks an overview"
    - "simultaneous information and power transfer for broadband wireless systems"
    - "wireless information and power transfer in multiuser ofdm systems"
    - "competition of wireless providers for atomic users"
    - "an axiomatic theory of fairness in network resource allocation"

Connected through hyperedge HE-6 (induced by source paper "throughput maximization for uav enabled wireless powered communication networks"):
  with members:
    - "capacity characterization of uav enabled two user broadcast channel"
    - "placement optimization of uav mounted mobile base stations"
    - "uav enabled wireless power transfer trajectory design and energy region characterization"
    - "joint trajectory and communication design for multi uav enabled wireless networks"
    - "energy efficient data collection in uav enabled wireless sensor network"
    - "joint trajectory and communication design for uav enabled multiple access"
    - "capacity of uav enabled multicast channel joint trajectory design and power allocation"
    - "uav enabled wireless power transfer trajectory design and energy optimization"

Connected through hyperedge HE-7 (induced by source paper "reusing wireless power transfer for backscatter assisted cooperation in wpcn"):
  with members:
    - "computation rate maximization for wireless powered mobile edge computing with binary computation offloading"
    - "multi antenna enabled cluster based cooperation in wireless powered communication networks"
    - "distributed scheduling in wireless powered communication network protocol design and performance analysis"
    - "joint offloading and computing optimization in wireless powered mobile edge computing systems"
    - "user cooperation for enhanced throughput fairness in wireless powered communication networks"
    - "distributed charging control in broadband wireless power transfer networks"
    - "wireless powered communication networks an overview"
    - "wireless powered communication opportunities and challenges"

Connected through hyperedge HE-8 (induced by source paper "backscatter assisted relaying in wireless powered communications network"):
  with members:
    - "computation rate maximization for wireless powered mobile edge computing with binary computation offloading"
    - "multi antenna enabled cluster based cooperation in wireless powered communication networks"
    - "distributed scheduling in wireless powered communication network protocol design and performance analysis"
    - "user cooperation for enhanced throughput fairness in wireless powered communication networks"
    - "distributed charging control in broadband wireless power transfer networks"
    - "wireless powered communication networks an overview"
    - "wireless powered communication opportunities and challenges"
    - "user cooperation in wireless powered communication networks"

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.NI(Networking and Internet Architecture)