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: "outage performance for cooperative noma transmission with an af relay"
  Abstract: This letter studies the outage performance of cooperative non-orthogonal multiple access (NOMA) network with the help of an amplify-and-forward relay. An accurate closed-form approximation for the exact outage probability is derived. Based on this, the asymptotic outage probability is investigated, which shows that cooperative NOMA achieves the same diversity order and the superior coding gain compared to cooperative orthogonal multiple access. It is also revealed that when the transmit power of relay is smaller than that of the base station, the outage performance improves as the distance between the relay and indirect link user decreases.

Connected through hyperedge HE-1 (induced by source paper "performance analysis of intelligent reflecting surface assisted noma networks"):
  with members:
    - "intelligent reflecting surface assisted multiple access with user pairing noma or oma"
    - "on the impact of phase shifting designs on irs noma"
    - "intelligent reflecting surface versus decode and forward how large surfaces are needed to beat relaying"
    - "secure wireless communication via intelligent reflecting surface"
    - "intelligent reflecting surface assisted non orthogonal multiple access"
    - "a vision of 6g wireless systems applications trends technologies and open research problems"
    - "a simple design of irs noma transmission"
    - "secure communications in a unified non orthogonal multiple access framework"

Connected through hyperedge HE-2 (induced by source paper "cooperative asynchronous non orthogonal multiple access with power minimization under qos constraints"):
  with members:
    - "an analysis of two user uplink asynchronous non orthogonal multiple access systems"
    - "exploiting full half duplex user relaying in noma systems"
    - "a survey on non orthogonal multiple access for 5g networks research challenges and future trends"
    - "wireless network level partial relay cooperation a stable throughput analysis"
    - "interference mitigation using asynchronous transmission and sampling diversity"
    - "cooperative non orthogonal multiple access with simultaneous wireless information and power transfer"
    - "asynchronous orthogonal differential decoding for multiple access channels"
    - "distributed beamforming in wireless multiuser relay interference networks with quantized feedback"

Connected through hyperedge HE-3 (induced by source paper "capacity and outage analysis of a dual hop decode and forward relay aided noma scheme"):
  with members:
    - "modeling and analysis of two way relay non orthogonal multiple access systems"
    - "non orthogonal multiple access for cooperative communications challenges opportunities and trends"
    - "performance analysis of a hybrid downlink uplink cooperative noma scheme"
    - "power domain non orthogonal multiple access noma in 5g systems potentials and challenges"
    - "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"
    - "dynamic user clustering and power allocation for uplink and downlink non orthogonal multiple access noma systems"
    - "towards 1 gbps ue in cellular systems understanding ultra dense small cell deployments"

Connected through hyperedge HE-4 (induced by source paper "capacity enhanced cooperative d2d systems over rayleigh fading channels with noma"):
  with members:
    - "short packet downlink transmission with non orthogonal multiple access"
    - "non orthogonal multiple access for cooperative communications challenges opportunities and trends"
    - "spatial and frequency wideband effects in millimeter wave massive mimo systems"
    - "channel estimation for tdd fdd massive mimo systems with channel covariance computing"
    - "resource allocation for downlink noma systems key techniques and open issues"
    - "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"
    - "joint beamforming and power splitting control in downlink cooperative swipt noma systems"

Connected through hyperedge HE-5 (induced by source paper "analysis of outage probabilities for cooperative noma users with imperfect csi"):
  with members:
    - "power domain non orthogonal multiple access noma in 5g systems potentials and challenges"
    - "a survey on non orthogonal multiple access for 5g networks research challenges and future trends"
    - "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)