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: "relay selection for cooperative noma"
  Abstract: This letter studies the impact of relay selection (RS) on the performance of cooperative non-orthogonal multiple access (NOMA). In particular, a two-stage RS strategy is proposed, and analytical results are developed to demonstrate that this two-stage strategy can achieve the minimal outage probability among all possible RS schemes, and realize the maximal diversity gain. The provided simulation results show that cooperative NOMA with this two-stage RS scheme outperforms that with the conventional max-min approach, and can also yield a significant performance gain over orthogonal multiple access.

Connected through hyperedge HE-1 (induced by source paper "on the performance of cooperative noma using mrc at road intersections in the presence of interference"):
  with members:
    - "outage analysis of cooperative noma using maximum ratio combining at intersections"
    - "performance analysis of cooperative communications at road intersections using stochastic geometry tools"
    - "vehicle to vehicle communications with urban intersection path loss models"
    - "cooperative non orthogonal multiple access with simultaneous wireless information and power transfer"
    - "on the outage probability of the full duplex interference limited relay channel"
    - "on the performance of non orthogonal multiple access in 5g systems with randomly deployed users"

Connected through hyperedge HE-2 (induced by source paper "performance evaluation of adaptive cooperative noma protocol at road junctions"):
  with members:
    - "outage analysis of cooperative noma using maximum ratio combining at intersections"
    - "performance analysis of cooperative communications at road intersections using stochastic geometry tools"
    - "vehicle to vehicle communications with urban intersection path loss models"
    - "on the performance of non orthogonal multiple access in 5g systems with randomly deployed users"

Connected through hyperedge HE-3 (induced by source paper "interplay between noma and other emerging technologies a survey"):
  with members:
    - "secure relaying in non orthogonal multiple access trusted and untrusted scenarios"
    - "securing downlink massive mimo noma networks with artificial noise"
    - "lens based millimeter wave reconfigurable antenna noma"
    - "what role can noma play in massive mimo"
    - "noma an information theoretic perspective"
    - "joint power and time allocation for noma mec offloading"
    - "multi beam noma for hybrid mmwave systems"
    - "exploiting full half duplex user relaying in noma systems"

Connected through hyperedge HE-4 (induced by source paper "non orthogonal multiple access noma how it meets 5g and beyond"):
  with members:
    - "securing downlink massive mimo noma networks with artificial noise"
    - "energy efficient joint user rb association and power allocation for uplink hybrid noma oma"
    - "capacity and outage analysis of a dual hop decode and forward relay aided noma scheme"
    - "energy efficient power allocation in uplink mmwave massive mimo with noma"
    - "optimal joint subcarrier and power allocation in noma is strongly np hard"
    - "power domain non orthogonal multiple access noma in 5g systems potentials and challenges"
    - "non orthogonal multiple access in large scale heterogeneous networks"
    - "a two phase power allocation scheme for crns employing noma"

Connected through hyperedge HE-5 (induced by source paper "secure users oriented downlink miso noma"):
  with members:
    - "exploiting inter user interference for secure massive non orthogonal multiple access"
    - "secure communications in noma system subcarrier assignment and power allocation"
    - "secrecy sum rate maximization in non orthogonal multiple access"
    - "on the spectral efficiency and security enhancements of noma assisted multicast unicast streaming"
    - "optimal joint power and subcarrier allocation for full duplex multicarrier non orthogonal multiple access systems"
    - "on the design of secure non orthogonal multiple access systems"
    - "energy efficient transmission design in non orthogonal multiple access"
    - "physical layer security in millimeter wave cellular networks"

Connected through hyperedge HE-6 (induced by source paper "performance analysis of ssk noma"):
  with members:
    - "derivation of the closed form ber expressions for dl noma over nakagami m fading channels"
    - "spatial modulation assisted multi antenna non orthogonal multiple access"
    - "power domain non orthogonal multiple access noma in 5g systems potentials and challenges"
    - "a fair power allocation approach to noma in multiuser siso systems"
    - "resource allocation for downlink noma systems key techniques and open issues"
    - "power and channel allocation for non orthogonal multiple access in 5g systems tractability and computation"
    - "non orthogonal multiple access in multi cell networks theory performance and practical challenges"
    - "fairness for non orthogonal multiple access in 5g systems"

Connected through hyperedge HE-7 (induced by source paper "fundamental limits of spectrum sharing for noma based cooperative relaying under a peak interference constraint"):
  with members:
    - "cognitive non orthogonal multiple access with cooperative relaying a new wireless frontier for 5g spectrum sharing"
    - "a survey on non orthogonal multiple access for 5g networks research challenges and future trends"
    - "on the performance of noma based cooperative relaying systems over rician fading channels"
    - "nonorthogonal multiple access in large scale underlay cognitive radio networks"
    - "lattice partition multiple access a new method of downlink non orthogonal multiuser transmissions"
    - "performance analysis of project and forward relaying in mixed mimo pinhole and rayleigh dual hop channel"
    - "impact of pointing errors on the performance of mixed rf fso dual hop transmission systems"
    - "a new formula for the ber of binary modulations with dual branch selection over generalized k"

Connected through hyperedge HE-8 (induced by source paper "outage analysis of cooperative noma using maximum ratio combining at intersections"):
  with members:
    - "performance analysis of cooperative communications at road intersections using stochastic geometry tools"
    - "power domain non orthogonal multiple access noma in 5g systems potentials and challenges"
    - "non orthogonal multiple access in large scale heterogeneous networks"
    - "full duplex multi antenna relay assisted cooperative non orthogonal multiple access"
    - "modeling and design of millimeter wave networks for highway vehicular communication"
    - "vehicle to vehicle communications with urban intersection path loss models"
    - "on the performance of non orthogonal multiple access in 5g systems with randomly deployed users"

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)