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: "a survey of millimeter wave mmwave communications for 5g opportunities and challenges"
  Abstract: With the explosive growth of mobile data demand, the fifth generation (5G) mobile network would exploit the enormous amount of spectrum in the millimeter wave (mmWave) bands to greatly increase communication capacity. There are fundamental differences between mmWave communications and existing other communication systems, in terms of high propagation loss, directivity, and sensitivity to blockage. These characteristics of mmWave communications pose several challenges to fully exploit the potential of mmWave communications, including integrated circuits and system design, interference management, spatial reuse, anti-blockage, and dynamics control. To address these challenges, we carry out a survey of existing solutions and standards, and propose design guidelines in architectures and protocols for mmWave communications. We also discuss the potential applications of mmWave communications in the 5G network, including the small cell access, the cellular access, and the wireless backhaul. Finally, we discuss relevant open research issues including the new physical layer technology, software-defined network architecture, measurements of network state information, efficient control mechanisms, and heterogeneous networking, which should be further investigated to facilitate the deployment of mmWave communication systems in the future 5G networks.

Connected through hyperedge HE-1 (induced by source paper "a distributed multi rf chain hybrid mmwave scheme for small cell systems"):
  with members:
    - "a tutorial on beam management for 3gpp nr at mmwave frequencies"
    - "multi beam noma for hybrid mmwave systems"
    - "multi cell hybrid millimeter wave systems pilot contamination and interference mitigation"
    - "optimal resource allocation for power efficient mc noma with imperfect channel state information"
    - "millimeter wave mimo prototype measurements and experimental results"
    - "measurement results for millimeter wave pure los mimo channels"
    - "multi user precoding and channel estimation for hybrid millimeter wave systems"
    - "cell free massive mimo versus small cells"

Connected through hyperedge HE-2 (induced by source paper "power and beam optimization for uplink millimeter wave hotspot communication systems"):
  with members:
    - "the role of asymptotic functions in network optimization and feasibility studies"
    - "adaptive beam frequency allocation algorithm with position uncertainty for millimeter wave mimo systems"
    - "overview of millimeter wave communications for fifth generation 5g wireless networks with a focus on propagation models"
    - "fundamental properties of solutions to utility maximization problems in wireless networks"
    - "elementary properties of positive concave mappings with applications to network planning and optimization"
    - "millimeter wave cellular networks a mac layer perspective"

Connected through hyperedge HE-3 (induced by source paper "multi cell hybrid millimeter wave systems pilot contamination and interference mitigation"):
  with members:
    - "a multi beam noma framework for hybrid mmwave systems"
    - "massive mimo has unlimited capacity"
    - "optimal resource allocation for power efficient mc noma with imperfect channel state information"
    - "massive mimo performance tdd versus fdd what do measurements say"
    - "coverage analysis for millimeter wave networks the impact of directional antenna arrays"
    - "where when and how mmwave is used in 5g and beyon"
    - "multi user precoding and channel estimation for hybrid millimeter wave systems"
    - "small scale local area and transitional millimeter wave propagation for 5g communications"

Connected through hyperedge HE-4 (induced by source paper "improving the coverage and spectral efficiency of millimeter wave cellular networks using device to device relays"):
  with members:
    - "modeling and analyzing millimeter wave cellular systems"
    - "optimal relay probing in millimeter wave cellular systems with device to device relaying"
    - "energy efficiency in relay assisted mmwave cellular networks"
    - "connectivity of millimeter wave networks with multi hop relaying"
    - "coverage and rate analysis for millimeter wave cellular networks"
    - "millimeter wave cellular wireless networks potentials and challenges"
    - "millimeter wave channel modeling and cellular capacity evaluation"
    - "analysis of blockage effects on urban cellular networks"

Connected through hyperedge HE-5 (induced by source paper "efficient beam training and channel estimation for millimeter wave communications under mobility"):
  with members:
    - "compressive channel estimation and tracking for large arrays in mm wave picocells"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "tracking mm wave channel dynamics fast beam training strategies under mobility"
    - "compressed sensing for wireless communications useful tips and tricks"
    - "tracking angles of departure and arrival in a mobile millimeter wave channel"
    - "training beam sequence design for millimeter wave mimo systems a pomdp framework"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"
    - "spatially sparse precoding in millimeter wave mimo systems"

Connected through hyperedge HE-6 (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"
    - "probabilistic omnidirectional path loss models for millimeter wave outdoor communications"
    - "heterogeneous cloud radio access networks a new perspective for enhancing spectral and energy efficiencies"
    - "optimal user cell association for massive mimo wireless networks"
    - "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-7 (induced by source paper "qos aware full duplex concurrent scheduling for millimeter wave wireless backhaul networks"):
  with members:
    - "full duplex amplify and forward relaying power and location optimization"
    - "full duplex millimeter wave communication"
    - "hierarchical codebook design for beamforming training in millimeter wave communication"
    - "exploiting device to device communications in joint scheduling of access and backhaul for mmwave small cells"
    - "wireless backhaul node placement for small cell networks"
    - "in band full duplex wireless challenges and opportunities"
    - "coding the beams improving beamforming training in mmwave communication system"

Connected through hyperedge HE-8 (induced by source paper "time fractional user association in millimeter wave mimo networks"):
  with members:
    - "probabilistic omnidirectional path loss models for millimeter wave outdoor communications"
    - "optimal user cell association for massive mimo wireless networks"
    - "spatially sparse precoding in millimeter wave mimo systems"
    - "distributed linear precoder optimization and base station selection for an uplink heterogeneous network"

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)