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 for enhanced throughput fairness in wireless powered communication networks"
  Abstract: This paper studies a novel user cooperation method in a wireless powered communication network (WPCN), where a pair of distributed terminal users first harvest wireless energy broadcasted by one energy node (EN) and then use the harvested energy to transmit information cooperatively to a destination node (DN). In particular, the two cooperating users exchange their independent information with each other to form a virtual antenna array and transmit jointly to the DN. By allowing each user to allocate part of its harvested energy to transmit the other's information, the proposed cooperation can effectively mitigate the user unfairness problem in WPCNs, where a user may suffer from very low data rate due to the poor energy harvesting performance and high data transmission consumptions. We derive the maximum common throughput achieved by the cooperation scheme through optimizing the time allocation on wireless energy transfer, user message exchange, and joint information transmissions. Through comparing with some representative benchmark schemes, our results demonstrate the effectiveness of the proposed user cooperation in enhancing the throughput performance under different setups.

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"
    - "distributed charging control in broadband wireless power transfer networks"
    - "wirelessly powered backscatter communication networks modeling coverage and capacity"

Connected through hyperedge HE-2 (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-3 (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"
    - "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"
    - "cognitive wireless powered network spectrum sharing models and throughput maximization"

Connected through hyperedge HE-4 (induced by source paper "finite horizon throughput maximization and sensing optimization in wireless powered devices over fading channels"):
  with members:
    - "a survey on mobile edge computing the communication perspective"
    - "a tutorial on thompson sampling"
    - "computation rate maximization for wireless powered mobile edge computing"
    - "non orthogonal multiple access schemes in wireless powered communication networks"
    - "battery powered devices in wpcns"
    - "on optimal policies in full duplex wireless powered communication networks"
    - "an adaptive transmission protocol for wireless powered cooperative communications"
    - "optimum wirelessly powered relaying"

Connected through hyperedge HE-5 (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"
    - "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"

Connected through hyperedge HE-6 (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"
    - "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"
    - "user cooperation in wireless powered communication networks"

Connected through hyperedge HE-7 (induced by source paper "multi antenna enabled cluster based cooperation in wireless powered communication networks"):
  with members:
    - "optimization and analysis of wireless powered multi antenna cooperative systems"
    - "group cooperation with optimal resource allocation 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"
    - "throughput optimization for massive mimo systems powered by wireless energy transfer"
    - "harvest then cooperate wireless powered cooperative communications"

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)