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: "optimal user cell association for massive mimo wireless networks"
  Abstract: The use of a very large number of antennas at each base station site (referred to as "Massive MIMO") is one of the most promising approaches to cope with the predicted wireless data traffic explosion. In combination with Time Division Duplex and with simple per-cell processing, it achieves large throughput per cell, low latency, and attractive power efficiency performance. Following the current wireless technology trend of moving to higher frequency bands and denser small cell deployments, a large number of antennas can be implemented within a small form factor even in small cell base stations. In a heterogeneous network formed by large (macro) and small cell BSs, a key system optimization problem consists of "load balancing", that is, associating users to BSs in order to avoid congested hot-spots and/or under-utilized infrastructure. In this paper, we consider the user-BS association problem for a massive MIMO heterogeneous network. We formulate the problem as a network utility maximization, and provide a centralized solution in terms of the fraction of transmission resources (time-frequency slots) over which each user is served by a given BS. Furthermore, we show that such a solution is physically realizable, i.e., there exists a sequence of integer scheduling configurations realizing (by time-sharing) the optimal fractions. While this solution is optimal, it requires centralized computation. Then, we also consider decentralized user-centric schemes, formulated as non-cooperative games where each user makes individual selfish association decisions based only on its local information. We identify a class of schemes such that their Nash equilibrium is very close to the global centralized optimum. Hence, these user-centric algorithms are attractive not only for their simplicity and fully decentralized implementation, but also because they operate near the system "social" optimum.

Connected through hyperedge HE-1 (induced by source paper "reinforcement learning based vehicle cell association algorithm for highly mobile millimeter wave communication"):
  with members:
    - "vehicular edge computing via deep reinforcement learning"
    - "wireless edge computing with latency and reliability guarantees"
    - "learning to optimize training deep neural networks for interference management"
    - "federated learning for ultra reliable low latency v2v communications"
    - "deep learning coordinated beamforming for highly mobile millimeter wave systems"
    - "ultra reliable and low latency wireless communication tail risk and scale"
    - "user association and load balancing for massive mimo through deep learning"
    - "load balancing user association in millimeter wave mimo networks"

Connected through hyperedge HE-2 (induced by source paper "user association in dense mmwave networks based on rate requirements"):
  with members:
    - "time fractional user association in millimeter wave mimo networks"
    - "maximum throughput scheduling for multi connectivity in millimeter wave networks"
    - "energy efficient user association and power allocation in millimeter wave based ultra dense networks with energy harvesting base stations"
    - "what will 5g be"
    - "user association for load balancing in heterogeneous cellular networks"

Connected through hyperedge HE-3 (induced by source paper "early acceptance matching game for user association in 5g cellular hetnet"):
  with members:
    - "load balancing user association in millimeter wave mimo networks"
    - "probabilistic omnidirectional path loss models for millimeter wave outdoor communications"
    - "matching theory for priority based cell association in the downlink of wireless small cell networks"
    - "user association for load balancing in heterogeneous cellular networks"

Connected through hyperedge HE-4 (induced by source paper "load balancing user association in millimeter wave mimo networks"):
  with members:
    - "time fractional user association in millimeter wave mimo networks"
    - "downlink cell association and load balancing for joint millimeter wave microwave cellular networks"
    - "large scale convex optimization for ultra dense cloud ran"
    - "a survey of millimeter wave mmwave communications for 5g opportunities and challenges"
    - "probabilistic omnidirectional path loss models for millimeter wave outdoor communications"
    - "heterogeneous cloud radio access networks a new perspective for enhancing spectral and energy efficiencies"
    - "distributed linear precoder optimization and base station selection for an uplink heterogeneous network"
    - "millimeter wave channel modeling and cellular capacity evaluation"

Connected through hyperedge HE-5 (induced by source paper "efficient c ran random access for iot devices learning links via recommendation systems"):
  with members:
    - "compressive channel estimation and multi user detection in c ran"
    - "a novel alternative to cloud ran for throughput densification coded pilots and fast user packet scheduling at remote radio heads"
    - "user activity detection in massive random access compressed sensing vs coded slotted aloha"
    - "rrh based massive mimo with on the fly pilot contamination control"
    - "random access protocols for massive mimo"
    - "directional training and fast sector based processing schemes for mmwave channels"
    - "user association and interference management in massive mimo hetnets"
    - "analysis of blockage effects on urban cellular networks"

Connected through hyperedge HE-6 (induced by source paper "resource allocation and power control in cooperative small cell networks in frequency selective channels with backhaul constraint"):
  with members:
    - "backhaul aware user association and resource allocation for energy constrained hetnets"
    - "tier aware resource allocation in ofdma macrocell small cell networks"
    - "sinr and throughput scaling in ultradense urban cellular networks"
    - "distributed pricing based user association for downlink heterogeneous cellular networks"
    - "user association for load balancing in heterogeneous cellular networks"
    - "resource allocation for downlink cellular ofdma systems part ii practical algorithms and optimal reuse factor"
    - "resource allocation for downlink cellular ofdma systems part i optimal allocation"

Connected through hyperedge HE-7 (induced by source paper "on the spectral efficiency of noncooperative uplink massive mimo systems"):
  with members:
    - "massive mimo ten myths and one critical question"
    - "massive mimo for maximal spectral efficiency how many users and pilots should be allocated"
    - "large system analysis of correlated mimo multiple access channels with arbitrary signaling in the presence of interference"
    - "on the capacity of large mimo block fading channels"
    - "mutual information of iid complex gaussian signals on block rayleigh faded channels"
    - "pilot contamination and precoding in multi cell tdd systems"

Connected through hyperedge HE-8 (induced by source paper "user association and load balancing for massive mimo through deep learning"):
  with members:
    - "massive mimo has unlimited capacity"
    - "joint power allocation and user association optimization for massive mimo systems"
    - "wireless power transfer in massive mimo aided hetnets with user association"
    - "massive mimo with multi cell mmse processing exploiting all pilots for interference suppression"
    - "user association and interference management in massive mimo hetnets"
    - "adam a method for stochastic optimization"

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)