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 cell search delay analysis for cellular networks with static users"
  Abstract: Cell search is the process for a user to detect its neighboring base stations (BSs) and make a cell selection decision. Due to the importance of beamforming gain in millimeter wave (mmWave) and massive MIMO cellular networks, the directional cell search delay performance is investigated. A cellular network with fixed BS and user locations is considered, so that strong temporal correlations exist for the SINR experienced at each BS and user. For Poisson cellular networks with Rayleigh fading channels, a closed-form expression for the spatially averaged mean cell search delay of all users is derived. This mean cell search delay for a noise-limited network (e.g., mmWave network) is proved to be infinite whenever the non-line-of-sight (NLOS) path loss exponent is larger than 2. For interference-limited networks, a phase transition for the mean cell search delay is shown to exist in terms of the number of BS antennas/beams $M$: the mean cell search delay is infinite when $M$ is smaller than a threshold and finite otherwise. Beam-sweeping is also demonstrated to be effective in decreasing the cell search delay, especially for the cell edge users.

Connected through hyperedge HE-1 (induced by source paper "secure communication in dynamic wireless ad hoc networks"):
  with members:
    - "k connectivity in random key graphs with unreliable links"
    - "tradeoff between delay and physical layer security in wireless networks"
    - "toward a tractable delay analysis in ultra dense networks"
    - "connectivity in secure wireless sensor networks under transmission constraints"
    - "on topological properties of wireless sensor networks under the q composite key predistribution scheme with on off channels"
    - "physical layer security in cellular networks a stochastic geometry approach"
    - "on the throughput cost of physical layer security in decentralized wireless networks"
    - "information propagation speed in mobile and delay tolerant networks"

Connected through hyperedge HE-2 (induced by source paper "bandwidth partitioning and downlink analysis in mmwave integrated access and backhaul for 5g"):
  with members:
    - "modeling and analyzing millimeter wave cellular systems"
    - "integrated mmwave access and backhaul in 5g bandwidth partitioning and downlink analysis"
    - "modeling and analysis of cellular networks using stochastic geometry a tutorial"
    - "joint backhaul access analysis of full duplex self backhauling heterogeneous networks"
    - "downlink and uplink cell association with traditional macrocells and millimeter wave small cells"
    - "enriched k tier hetnet model to enable the analysis of user centric small cell deployments"
    - "analysis of massive mimo enabled downlink wireless backhauling for full duplex small cells"
    - "coverage in heterogeneous downlink millimeter wave cellular networks"

Connected through hyperedge HE-3 (induced by source paper "fast and reliable initial access with random beamforming for mmwave networks"):
  with members:
    - "a tutorial on beam management for 3gpp nr at mmwave frequencies"
    - "reducing initial cell search latency in mmwave networks"
    - "design and analysis of initial access in millimeter wave cellular networks"
    - "initial access in 5g mmwave cellular networks"
    - "performance analysis of outdoor mmwave ad hoc networks"
    - "tractable resource management with uplink decoupled millimeter wave overlay in ultra dense cellular networks"
    - "context information based initial cell search for millimeter wave 5g cellular networks"
    - "context information for fast cell discovery in mm wave 5g networks"

Connected through hyperedge HE-4 (induced by source paper "reducing initial cell search latency in mmwave networks"):
  with members:
    - "design and analysis of initial access in millimeter wave cellular networks"
    - "initial access in 5g mmwave cellular networks"
    - "tractable resource management with uplink decoupled millimeter wave overlay in ultra dense cellular networks"
    - "millimeter wave cellular networks a mac layer perspective"
    - "the transitional behavior of interference in millimeter wave networks and its impact on medium access control"
    - "analysis of blockage effects on urban cellular networks"
    - "modeling and analysis of k tier downlink 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.IT(Information Theory)