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: "user cooperation in wireless powered communication networks"
  Abstract: This paper studies user cooperation in the emerging wireless powered communication network (WPCN) for throughput optimization. For the purpose of exposition, we consider a two-user WPCN, in which one hybrid access point (H-AP) broadcasts wireless energy to two distributed users in the downlink (DL) and the users transmit their independent information using their individually harvested energy to the H-AP in the uplink (UL) through time-division-multiple-access (TDMA). We propose user cooperation in the WPCN where the user which is nearer to the H-AP and has a better channel for DL energy harvesting and UL information transmission uses part of its allocated UL time and DL harvested energy to help to relay the far user's information to the H-AP, in order to achieve more balanced throughput optimization. We maximize the weighted sum-rate (WSR) of the two users by jointly optimizing the time and power allocations in the network for both wireless energy transfer in the DL and wireless information transmission and relaying in the UL. Simulation results show that the proposed user cooperation scheme can effectively improve the achievable throughput in the WPCN with desired user fairness.

Connected through hyperedge HE-1 (induced by source paper "learning and fairness in energy harvesting a maximin multi armed bandits approach"):
  with members:
    - "distributed user association in energy harvesting dense small cell networks a mean field multi armed bandit approach"
    - "online learning schemes for power allocation in energy harvesting communications"
    - "energy harvesting wireless communications a review of recent advances"
    - "throughput optimization for massive mimo systems powered by wireless energy transfer"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "throughput maximization in wireless powered communication networks"

Connected through hyperedge HE-2 (induced by source paper "common throughput maximization for uav enabled interference channel with wireless powered communications"):
  with members:
    - "uav communications for 5g and beyond recent advances and future trends"
    - "fundamentals of wireless information and power transfer from rf energy harvester models to signal and system designs"
    - "capacity characterization of uav enabled two user broadcast channel"
    - "cellular enabled uav communication a connectivity constrained trajectory optimization perspective"
    - "optimal 1d trajectory design for uav enabled multiuser wireless power transfer"
    - "minimum throughput maximization in uav aided wireless powered communication networks"
    - "a tutorial on uavs for wireless networks applications challenges and open problems"
    - "uav enabled wireless power transfer with directional antenna a two user case"

Connected through hyperedge HE-3 (induced by source paper "online policies for throughput maximization of energy constrained wireless powered communication systems"):
  with members:
    - "optimization of energy constrained wireless powered communication networks with heterogeneous nodes"
    - "wireless power meets energy harvesting a joint energy allocation approach in ofdm based system"
    - "resource allocation and fairness in wireless powered cooperative cognitive radio networks"
    - "battery powered devices in wpcns"
    - "on optimal policies in full duplex wireless powered communication networks"
    - "an overview of sustainable green 5g networks"
    - "dynamic base station operation in large scale green cellular networks"
    - "optimal design of non orthogonal multiple access with wireless power transfer"

Connected through hyperedge HE-4 (induced by source paper "an energy efficient controller for wirelessly powered communication networks"):
  with members:
    - "swipt using hybrid arq over time varying channels"
    - "optimal and near optimal policies for wireless power transfer in energy limited and power limited scenarios"
    - "joint sum rate and error probability optimization finite blocklength analysis"
    - "joint transfer of energy and information in a two hop relay channel"
    - "optimal energy and data routing in networks with energy cooperation"
    - "battery powered devices in wpcns"
    - "wireless powered relaying with finite block length codes"
    - "on wireless energy and information transfer in relay networks"

Connected through hyperedge HE-5 (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"
    - "distributed wireless power transfer with energy feedback"
    - "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"

Connected through hyperedge HE-6 (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-7 (induced by source paper "collaborative computation offloading in wireless powered mobile edge computing systems"):
  with members:
    - "joint computation and communication cooperation for energy efficient mobile edge computing"
    - "wireless powered user cooperative computation in mobile edge computing systems"
    - "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"
    - "multiuser computation offloading and downloading for edge computing with virtualization"
    - "online learning for offloading and autoscaling in energy harvesting mobile edge computing"
    - "price based distributed offloading for mobile edge computing with computation capacity constraints"
    - "a survey on mobile edge computing the communication perspective"

Connected through hyperedge HE-8 (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"
    - "placement optimization of energy and information access points 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.IT(Information Theory)