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 association in 5g networks a survey and an outlook"
  Abstract: The fifth generation (5G) mobile networks are envisioned to support the deluge of data traffic with reduced energy consumption and improved quality of service (QoS) provision. To this end, key enabling technologies, such as heterogeneous networks (HetNets), massive multiple-input multiple-output (MIMO), and millimeter wave (mmWave) techniques, have been identified to bring 5G to fruition. Regardless of the technology adopted, a user association mechanism is needed to determine whether a user is associated with a particular base station (BS) before data transmission commences. User association plays a pivotal role in enhancing the load balancing, the spectrum efficiency, and the energy efficiency of networks. The emerging 5G networks introduce numerous challenges and opportunities for the design of sophisticated user association mechanisms. Hence, substantial research efforts are dedicated to the issues of user association in HetNets, massive MIMO networks, mmWave networks, and energy harvesting networks. We introduce a taxonomy as a framework for systematically studying the existing user association algorithms. Based on the proposed taxonomy, we then proceed to present an extensive overview of the state-of-the-art in user association algorithms conceived for HetNets, massive MIMO, mmWave, and energy harvesting networks. Finally, we summarize the challenges as well as opportunities of user association in 5G and provide design guidelines and potential solutions for sophisticated user association mechanisms.

Connected through hyperedge HE-1 (induced by source paper "a tutorial on beam management for 3gpp nr at mmwave frequencies"):
  with members:
    - "statistical blockage modeling and robustness of beamforming in millimeter wave systems"
    - "adaptive beamwidth selection for contention based access periods in millimeter wave wlans"
    - "standalone and non standalone beam management for 3gpp nr at mmwaves"
    - "study of realistic antenna patterns in 5g mmwave cellular scenarios"
    - "initial access frameworks for 3gpp nr at mmwave frequencies"
    - "on the beamformed broadcast signaling for millimeter wave cell discovery performance analysis and design insight"
    - "caching meets millimeter wave communications for enhanced mobility management in 5g networks"
    - "improved handover through dual connectivity in 5g mmwave mobile networks"

Connected through hyperedge HE-2 (induced by source paper "resource allocation using gradient boosting aided deep q network for iot in c rans"):
  with members:
    - "bit level optimized neural network for multi antenna channel quantization"
    - "learning to optimize training deep neural networks for interference management"
    - "an introduction to deep reinforcement learning"
    - "mimo channel information feedback using deep recurrent network"
    - "deep forest"
    - "model driven deep learning for physical layer communications"
    - "deep forest towards an alternative to deep neural networks"
    - "xgboost a scalable tree boosting system"

Connected through hyperedge HE-3 (induced by source paper "sdn enabled mimo heterogeneous cooperative networks with flexible cell association"):
  with members:
    - "toward a realistic assessment of multiple antenna hcns residual additive transceiver hardware impairments and channel aging"
    - "downlink mimo hcns with residual transceiver hardware impairments"
    - "an overview of load balancing in hetnets old myths and open problems"
    - "a tractable model for noncoherent joint transmission base station cooperation"
    - "what will 5g be"
    - "downlink mimo hetnets modeling ordering results and performance analysis"
    - "downlink multi antenna heterogeneous cellular network with load balancing"
    - "heterogeneous cellular networks with flexible cell association a comprehensive downlink sinr analysis"

Connected through hyperedge HE-4 (induced by source paper "robust resource allocation for pd noma based miso heterogeneous networks with comp technology"):
  with members:
    - "radio resource allocation for device to device underlay communication using hypergraph theory"
    - "optimal joint power and subcarrier allocation for full duplex multicarrier non orthogonal multiple access systems"
    - "optimal dynamic point selection for power minimization in multiuser downlink comp"
    - "optimal stochastic coordinated beamforming for wireless cooperative networks with csi uncertainty"
    - "low complexity delay constrained beamforming for multi user mimo systems with imperfect csit"
    - "robust monotonic optimization framework for multicell miso systems"
    - "worst case sinr constrained robust coordinated beamforming for multicell wireless systems"
    - "probabilistic sinr constrained robust transmit beamforming a bernstein type inequality based conservative approach"

Connected through hyperedge HE-5 (induced by source paper "edge and central cloud computing a perfect pairing for high energy efficiency and low latency"):
  with members:
    - "spectral and energy efficiency of uplink d2d underlaid massive mimo cellular networks"
    - "performance characterization of a real time massive mimo system with los mobile channels"
    - "a survey on mobile edge computing the communication perspective"
    - "mobile edge computing a survey on architecture and computation offloading"
    - "joint offloading and computing optimization in wireless powered mobile edge computing systems"
    - "energy efficient resource allocation for mobile edge computing based augmented reality applications"
    - "energy efficient resource allocation for mobile edge computation offloading"
    - "computation offloading decisions for reducing completion time"

Connected through hyperedge HE-6 (induced by source paper "initial access frameworks for 3gpp nr at mmwave frequencies"):
  with members:
    - "adaptive beamwidth selection for contention based access periods in millimeter wave wlans"
    - "a tutorial on beam management for 3gpp nr at mmwave frequencies"
    - "improved handover through dual connectivity in 5g mmwave mobile networks"
    - "5g millimeter wave cellular system capacity with fully digital beamforming"
    - "initial access in 5g mmwave cellular networks"
    - "directional cell discovery in millimeter wave cellular networks"
    - "millimeter wave cellular wireless networks potentials and challenges"
    - "millimeter wave channel modeling and cellular capacity evaluation"

Connected through hyperedge HE-7 (induced by source paper "decentralized computation offloading and resource allocation in heterogeneous networks with mobile edge computing"):
  with members:
    - "a survey on mobile edge computing the communication perspective"
    - "computation rate maximization for wireless powered mobile edge computing"
    - "decentralized computation offloading game for mobile cloud computing"
    - "joint optimization of radio and computational resources for multicell mobile edge computing"
    - "matching theory for future wireless networks fundamentals and applications"
    - "femtocell networks a survey"

Connected through hyperedge HE-8 (induced by source paper "learning oriented cross entropy approach to user association in load balanced hetnet"):
  with members:
    - "utility energy efficiency oriented user association with power control in heterogeneous networks"
    - "backhaul aware user association and resource allocation for energy constrained hetnets"
    - "distributed pricing based user association for downlink heterogeneous cellular networks"
    - "user association for load balancing in heterogeneous cellular 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)