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: "directional initial access for millimeter wave cellular systems"
  Abstract: The millimeter wave (mmWave) bands have recently attracted considerable interest for next-generation cellular systems due to the massive available bandwidths at these frequencies. However, a key challenge in designing mmWave cellular systems is initial access -- the procedure by which a mobile establishes an initial link-layer connection to a base station cell. MmWave communication relies on highly directional transmissions and the initial access procedure must thus provide a mechanism by which initial transmission directions can be searched in a potentially large angular space. Design options are compared considering different scanning and signaling procedures to evaluate access delay and system overhead. The channel structure and multiple access issues are also considered. The analysis demonstrates significant benefits of low-resolution fully digital architectures in comparison to single stream analog beamforming.

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 "improved handover through dual connectivity in 5g mmwave mobile networks"):
  with members:
    - "adaptive beamwidth selection for contention based access periods in millimeter wave wlans"
    - "performance comparison of dual connectivity and hard handover for lte 5g tight integration"
    - "channel dynamics and snr tracking in millimeter wave cellular systems"
    - "transport layer performance in 5g mmwave cellular"
    - "a framework for end to end evaluation of 5g mmwave cellular networks in ns 3"
    - "multi connectivity in 5g mmwave cellular networks"
    - "uplink based framework for control plane applications in 5g mmwave cellular networks"
    - "comparative analysis of initial access techniques in 5g mmwave cellular networks"

Connected through hyperedge HE-3 (induced by source paper "improved target acquisition rates with feedback codes"):
  with members:
    - "comparative analysis of initial access techniques in 5g mmwave cellular networks"
    - "extrinsic jensen shannon divergence applications to variable length coding"
    - "searching with measurement dependent noise"
    - "collaborative 20 questions for target localization"
    - "near optimal adaptive compressed sensing"
    - "optimal multiband joint detection for spectrum sensing in cognitive radio networks"

Connected through hyperedge HE-4 (induced by source paper "design and analysis of initial access in millimeter wave cellular networks"):
  with members:
    - "modeling and analyzing millimeter wave cellular systems"
    - "initial beam association in millimeter wave cellular systems analysis and design insights"
    - "tractable resource management with uplink decoupled millimeter wave overlay in ultra dense cellular networks"
    - "comparative analysis of initial access techniques in 5g mmwave cellular networks"
    - "beamforming tradeoffs for initial ue discovery in millimeter wave mimo systems"
    - "stochastic geometry modeling and analysis of multi tier millimeter wave cellular networks"
    - "millimeter wave cellular networks a mac layer perspective"
    - "on the feasibility of sharing spectrum licenses in mmwave cellular systems"

Connected through hyperedge HE-5 (induced by source paper "uplink based framework for control plane applications in 5g mmwave cellular networks"):
  with members:
    - "towards an appropriate beamforming scheme for initial cell discovery in mmw 5g cellular networks"
    - "channel dynamics and snr tracking in millimeter wave cellular systems"
    - "initial access in 5g mmwave cellular networks"
    - "multi connectivity in 5g mmwave cellular networks"
    - "towards an appropriate receiver beamforming scheme for millimeter wave communication a power consumption based comparison"
    - "comparative analysis of initial access techniques in 5g mmwave cellular networks"
    - "context information for fast cell discovery in mm wave 5g networks"
    - "millimeter wave cellular networks a mac layer perspective"

Connected through hyperedge HE-6 (induced by source paper "initial access in 5g mmwave cellular networks"):
  with members:
    - "performance comparison of dual connectivity and hard handover for lte 5g tight integration"
    - "channel dynamics and snr tracking in millimeter wave cellular systems"
    - "multi connectivity in 5g mmwave cellular networks"
    - "context information based initial cell search for millimeter wave 5g cellular networks"
    - "comparative analysis of initial access techniques in 5g mmwave cellular networks"
    - "context information for fast cell discovery in mm wave 5g networks"
    - "millimeter wave cellular networks a mac layer perspective"
    - "directional cell discovery in millimeter wave cellular networks"

Connected through hyperedge HE-7 (induced by source paper "multi connectivity in 5g mmwave cellular networks"):
  with members:
    - "initial access in 5g mmwave cellular networks"
    - "comparative analysis of initial access techniques in 5g mmwave cellular networks"
    - "context information for fast cell discovery in mm wave 5g networks"
    - "millimeter wave cellular networks a mac layer perspective"
    - "handoff rate and coverage analysis in multi tier heterogeneous networks"
    - "3 d statistical channel model for millimeter wave outdoor mobile broadband communications"
    - "directional cell discovery in millimeter wave cellular networks"
    - "coverage and rate analysis for millimeter wave cellular networks"

Connected through hyperedge HE-8 (induced by source paper "channel dynamics and snr tracking in millimeter wave cellular systems"):
  with members:
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "comparative analysis of initial access techniques in 5g mmwave cellular networks"
    - "probabilistic omnidirectional path loss models for millimeter wave outdoor communications"
    - "3 d statistical channel model for millimeter wave outdoor mobile broadband communications"
    - "directional cell discovery in millimeter wave cellular networks"
    - "millimeter wave cellular wireless networks potentials and challenges"
    - "millimeter wave channel modeling and cellular capacity evaluation"
    - "five disruptive technology directions for 5g"

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)