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: "green cellular networks a survey some research issues and challenges"
  Abstract: Energy efficiency in cellular networks is a growing concern for cellular operators to not only maintain profitability, but also to reduce the overall environment effects. This emerging trend of achieving energy efficiency in cellular networks is motivating the standardization authorities and network operators to continuously explore future technologies in order to bring improvements in the entire network infrastructure. In this article, we present a brief survey of methods to improve the power efficiency of cellular networks, explore some research issues and challenges and suggest some techniques to enable an energy efficient or "green" cellular network. Since base stations consume a maximum portion of the total energy used in a cellular system, we will first provide a comprehensive survey on techniques to obtain energy savings in base stations. Next, we discuss how heterogeneous network deployment based on micro, pico and femto-cells can be used to achieve this goal. Since cognitive radio and cooperative relaying are undisputed future technologies in this regard, we propose a research vision to make these technologies more energy efficient. Lastly, we explore some broader perspectives in realizing a "green" cellular network technology

Connected through hyperedge HE-1 (induced by source paper "spatial and temporal management of cellular hetnets with multiple solar powered drones"):
  with members:
    - "user association and bandwidth allocation for terrestrial and aerial base stations with backhaul considerations"
    - "survey of important issues in uav communication networks"
    - "designing and implementing future aerial communication networks"
    - "a hybrid energy sharing framework for green cellular networks"
    - "green networking in cellular hetnets a unified radio resource management framework with base station on off switching"
    - "the new frontier in ran heterogeneity multi tier drone cells"
    - "wireless communications with unmanned aerial vehicles opportunities and challenges"
    - "unmanned aerial vehicle with underlaid device to device communications performance and tradeoffs"

Connected through hyperedge HE-2 (induced by source paper "a throughput and energy efficiency scheme for unlicensed massive machine type communications"):
  with members:
    - "finite blocklength communications in smart grids for dynamic spectrum access and locally licensed scenarios"
    - "5g wireless network slicing for embb urllc and mmtc a communication theoretic view"
    - "energy efficiency of an unlicensed wireless network in the presence of retransmissions"
    - "increasing the throughput of an unlicensed wireless network through retransmissions"
    - "massive machine type communications in 5g physical and mac layer solutions"
    - "next generation m2m cellular networks challenges and practical considerations"
    - "a survey on internet of things from industrial market perspective"
    - "on the joint impact of beamwidth and orientation error on throughput in directional wireless poisson networks"

Connected through hyperedge HE-3 (induced by source paper "joint long term admission control and beamforming in green downlink networks offline and online approaches"):
  with members:
    - "joint power and admission control based on channel distribution information a novel two timescale approach"
    - "context aware mobility management in hetnets a reinforcement learning approach"
    - "joint power and admission control via linear programming deflation"
    - "a decentralized method for joint admission control and beamforming in coordinated multicell downlink"
    - "distributed robust multicell coordinated beamforming with imperfect csi an admm approach"

Connected through hyperedge HE-4 (induced by source paper "energy sustainable paradigms and methods for future mobile networks a survey"):
  with members:
    - "information exchange in randomly deployed dense wsns with wireless energy harvesting capabilities"
    - "a stochastic geometry based demand response management framework for cellular networks powered by smart grid"
    - "fog computing based radio access networks issues and challenges"
    - "a hybrid energy sharing framework for green cellular networks"
    - "recent advances in cloud radio access networks system architectures key techniques and open issues"
    - "green networking in cellular hetnets a unified radio resource management framework with base station on off switching"
    - "online ski rental for on off scheduling of energy harvesting base stations"
    - "dynamic clustering and on off strategies for wireless small cell networks"

Connected through hyperedge HE-5 (induced by source paper "robust energy efficient beamforming in misome swipt systems with proportional secrecy rate"):
  with members:
    - "robust secrecy energy efficient beamforming in misome swipt systems with proportional fairness"
    - "rf based energy harvesting in decode and forward relaying systems ergodic and outage capacities"
    - "secure beamforming in full duplex swipt systems with loopback self interference cancellation"
    - "large scale multiantenna multisine wireless power transfer"
    - "dynamic cross layer beamforming in hybrid powered communication systems with harvest use trade strategy"
    - "joint optimization of power and data transfer in multiuser mimo systems"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "network densification in 5g from the short range communications perspective"

Connected through hyperedge HE-6 (induced by source paper "fog massive mimo a user centric seamless hot spot architecture"):
  with members:
    - "a novel alternative to cloud ran for throughput densification coded pilots and fast user packet scheduling at remote radio heads"
    - "realizing the tactile internet haptic communications over next generation 5g cellular networks"
    - "modeling and analysis of cellular networks using stochastic geometry a tutorial"
    - "ergodic spectral efficiency in mimo cellular networks"
    - "unique coverage in boolean models"
    - "system level performance evaluation of lte v2x network"
    - "an uplink downlink duality for cloud radio access network"
    - "rrh based massive mimo with on the fly pilot contamination control"

Connected through hyperedge HE-7 (induced by source paper "optimal and low complexity dynamic spectrum access for rf powered ambient backscatter system with online reinforcement learning"):
  with members:
    - "reinforcement learning approach for rf powered cognitive radio network with ambient backscatter"
    - "stackelberg game for distributed time scheduling in rf powered backscatter cognitive radio networks"
    - "energy efficient scheduling for loss tolerant iot applications with uninformed transmitter"
    - "inference from randomized transmissions by many backscatter sensors"
    - "ambient backscatter communications a contemporary survey"
    - "mimo wiretap channel under receiver side power constraints with applications to wireless power transfer and cognitive radio"
    - "wirelessly powered backscatter communication networks modeling coverage and capacity"
    - "cognitive and energy harvesting based d2d communication in cellular networks stochastic geometry modeling and analysis"

Connected through hyperedge HE-8 (induced by source paper "rf based energy harvesting in decode and forward relaying systems ergodic and outage capacities"):
  with members:
    - "smart charging for electric vehicles a survey from the algorithmic perspective"
    - "distributed hybrid power state estimation under pmu sampling phase errors"
    - "distributed clock skew and offset estimation in wireless sensor networks asynchronous algorithm and convergence analysis"
    - "distributed power splitting for swipt in relay interference channels using game theory"
    - "on the efficiency of far field wireless power transfer"
    - "power allocation strategies in energy harvesting wireless cooperative networks"
    - "relaying protocols for wireless energy harvesting and information processing"
    - "wireless information transfer with opportunistic energy harvesting"

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)