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: "resource allocation techniques for wireless powered communication networks with energy storage constraint"
  Abstract: This paper studies multi-user wireless powered communication networks, where energy constrained users charge their energy storages by scavenging energy of the radio frequency signals radiated from a hybrid access point (H-AP). The energy is then utilized for the users' uplink information transmission to the H-AP in time division multiple access mode. In this system, we aim to maximize the uplink sum rate performance by jointly optimizing energy and time resource allocation for multiple users in both infinite capacity and finite capacity energy storage cases. First, when the users are equipped with the infinite capacity energy storages, we derive the optimal downlink energy transmission policy at the H-AP. Based on this result, analytical resource allocation solutions are obtained. Next, we propose the optimal energy and time allocation algorithm for the case where each user has finite capacity energy storage. Simulation results confirm that the proposed algorithms offer 30% average sum rate performance gain over conventional schemes.

Connected through hyperedge HE-1 (induced by source paper "simultaneous wireless information and power transfer for decode and forward multihop relay systems in energy constrained iot networks"):
  with members:
    - "end to end throughput maximization for underlay multi hop cognitive radio networks with rf energy harvesting"
    - "retrodirective multi user wireless power transfer with massive mimo"
    - "simultaneous information and energy flow for iot relay systems with crowd harvesting"
    - "wireless powered communication opportunities and challenges"
    - "energy harvesting wireless communications a review of recent advances"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "application of smart antenna technologies in simultaneous wireless information and power transfer"
    - "wireless information and power transfer a dynamic power splitting approach"

Connected through hyperedge HE-2 (induced by source paper "secrecy throughput maximization for full duplex wireless powered iot networks under fairness constraints"):
  with members:
    - "energy sustainable iot with individual qos constraints through miso swipt multicasting"
    - "exploiting interference for secrecy wireless information and power transfer"
    - "power efficient and secure wpcns with hardware impairments and non linear eh circuit"
    - "throughput optimization for massive mimo systems powered by wireless energy transfer"
    - "full duplex wireless powered communication network with energy causality"
    - "mimo broadcasting for simultaneous wireless information and power transfer"

Connected through hyperedge HE-3 (induced by source paper "group cooperation with optimal resource allocation in wireless powered communication networks"):
  with members:
    - "resource allocation and fairness in wireless powered cooperative cognitive radio networks"
    - "wireless powered communication networks an overview"
    - "wireless powered cooperative communications power splitting relaying with energy accumulation"
    - "wireless powered communication opportunities and challenges"
    - "relay selection in wireless powered cooperative networks with energy storage"
    - "energy harvesting wireless communications a review of recent advances"
    - "placement optimization of energy and information access points in wireless powered communication networks"
    - "collaborative wireless energy and information transfer in interference channel"

Connected through hyperedge HE-4 (induced by source paper "performance analysis of energy buffer aided wireless powered communication"):
  with members:
    - "wireless powered communication networks an overview"
    - "a discrete time switching protocol for wireless powered communications with energy accumulation"
    - "on off transmission policy for wireless powered communication with energy storage"
    - "throughput maximization in wireless powered communication networks"
    - "on online energy harvesting in multiple access communication systems"
    - "wireless information and power transfer architecture design and rate energy tradeoff"

Connected through hyperedge HE-5 (induced by source paper "wireless information and power transfer nonlinearity waveform design and rate energy tradeoff"):
  with members:
    - "waveform design for wireless power transfer with limited feedback"
    - "wirelessly powered backscatter communications waveform design and snr energy tradeoff"
    - "large scale multiantenna multisine wireless power transfer"
    - "wireless information and power transfer over an awgn channel nonlinearity and asymmetric gaussian signaling"
    - "prototyping and experimentation of a closed loop wireless power transmission with channel acquisition and waveform optimization"
    - "low complexity adaptive multisine waveform design for wireless power transfer"
    - "waveform optimization for radio frequency wireless power transfer"
    - "waveform design for wireless power 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)