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: "intelligent reflecting surface assisted non orthogonal multiple access"
  Abstract: Intelligent reflecting surface (IRS) which consists of a large number of low-cost passive reflecting elements and can digitally manipulating electromagnetic waves, is a new and disruptive technology to achieve spectrum- and energy-efficient as well as cost-efficient wireless networks. In this paper, we consider an IRS-assisted non-orthogonal-multiple-access (NOMA) system in which a base station (BS) transmits superposed downlink signals to multiple users. In order to optimize the rate performance and ensure user fairness, we maximize the minimum decoding signal-to-interference-plus-noise-ratio (SINR) (i.e., equivalently the rate) of all users, by jointly optimizing the power allocation at the BS and the phase shifts at the passive IRS. However, the formulated problem is non-convex and difficult to be solved optimally. By leveraging the block coordinated decent, successive convex optimization and semidefinite relaxation techniques, an efficient algorithm is further proposed to obtain a sub-optimal solution. The convergence is proved and the complexity is analyzed for the proposed algorithm. Also, a low-complexity solving scheme is proposed. Simulation results show that the IRS can enhance the rate performance for downlink NOMA systems significantly even for the scenario in which users have the same or comparable channel strength(es), and the practical IRS with a 3-bit phase quantizer is sufficient to ensure the rate degradation of less than 3.4% compared to the case of continuous phase shifts.

Connected through hyperedge HE-1 (induced by source paper "mimo noma networks relying on reconfigurable intelligent surface a signal cancellation based design"):
  with members:
    - "intelligent reflecting surface assisted multiple access with user pairing noma or oma"
    - "enabling panoramic full angle reflection via aerial intelligent reflecting surface"
    - "performance analysis of intelligent reflecting surface assisted noma networks"
    - "miso wireless communication systems via intelligent reflecting surfaces"
    - "large intelligent surface antennas lisa making reflective radios smart"
    - "reflection probability in wireless networks with metasurface coated environmental objects an approach based on random spatial processes"
    - "capacity characterization for intelligent reflecting surface aided mimo communication"
    - "channel capacity optimization using reconfigurable intelligent surfaces in indoor mmwave environments"

Connected through hyperedge HE-2 (induced by source paper "resource allocation in intelligent reflecting surface assisted noma systems"):
  with members:
    - "joint active and passive beamforming optimization for intelligent reflecting surface assisted swipt under qos constraints"
    - "capacity characterization for intelligent reflecting surface aided mimo communication"
    - "power efficient irs assisted noma"
    - "intelligent reflecting surface meets ofdm protocol design and rate maximization"
    - "intelligent reflecting surface design for mimo system by maximizing sum path gains"
    - "a simple design of irs noma transmission"
    - "towards smart radio environment for wireless communications via intelligent reflecting surfaces a comprehensive survey"
    - "joint beamforming design in multi cluster miso noma intelligent reflecting surface aided downlink communication networks"

Connected through hyperedge HE-3 (induced by source paper "intelligent reflecting surface assisted secure wireless communications with multiple transmit and multiple receive antennas"):
  with members:
    - "secure wireless communication via intelligent reflecting surface"
    - "a survey of optimization approaches for wireless physical layer security"
    - "capacity characterization for intelligent reflecting surface aided mimo communication"
    - "resource allocation for secure irs assisted multiuser miso systems"
    - "secure transmission strategy for intelligent reflecting surface enhanced wireless system"
    - "enabling secure wireless communications via intelligent reflecting surfaces"
    - "indoor signal focusing with deep learning designed reconfigurable intelligent surfaces"
    - "weighted sum power maximization for intelligent reflecting surface aided swipt"

Connected through hyperedge HE-4 (induced by source paper "intelligent reflecting surface assisted multi user ofdma channel estimation and training design"):
  with members:
    - "intelligent reflecting surface assisted multiple access with user pairing noma or oma"
    - "parallel factor decomposition channel estimation in ris assisted multi user miso communication"
    - "intelligent reflecting surface with discrete phase shifts channel estimation and passive beamforming"
    - "secure wireless communication via intelligent reflecting surface"
    - "cascaded channel estimation for large intelligent metasurface assisted massive mimo"
    - "channel estimation for intelligent reflecting surface assisted multiuser communications framework algorithms and analysis"
    - "capacity characterization for intelligent reflecting surface aided mimo communication"
    - "progressive channel estimation and passive beamforming for intelligent reflecting surface with discrete phase shifts"

Connected through hyperedge HE-5 (induced by source paper "capacity and optimal resource allocation for irs assisted multi user communication systems"):
  with members:
    - "large intelligent surface antennas lisa making reflective radios smart"
    - "robust and secure wireless communications via intelligent reflecting surfaces"
    - "capacity characterization for intelligent reflecting surface aided mimo communication"
    - "power efficient irs assisted noma"
    - "a vision of 6g wireless systems applications trends technologies and open research problems"
    - "a simple design of irs noma transmission"
    - "irs enhanced ofdma joint resource allocation and passive beamforming optimization"
    - "mimo assisted networks relying on large intelligent surfaces a stochastic geometry model"

Connected through hyperedge HE-6 (induced by source paper "joint power control and passive beamforming in irs assisted spectrum sharing"):
  with members:
    - "intelligent reflecting surface assisted multiple access with user pairing noma or oma"
    - "joint active and passive beamforming optimization for intelligent reflecting surface assisted swipt under qos constraints"
    - "holographic mimo surfaces for 6g wireless networks opportunities challenges and trends"
    - "secure wireless communication via intelligent reflecting surface"
    - "capacity characterization for intelligent reflecting surface aided mimo communication"
    - "intelligent reflecting surface meets ofdm protocol design and rate maximization"
    - "enabling secure wireless communications via intelligent reflecting surfaces"
    - "intelligent reflecting surface assisted secrecy communication is artificial noise helpful or not"

Connected through hyperedge HE-7 (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"
    - "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"
    - "towards smart and reconfigurable environment intelligent reflecting surface aided wireless network"

Connected through hyperedge HE-8 (induced by source paper "analysis and optimization of an intelligent reflecting surface assisted system with interference"):
  with members:
    - "analysis and optimization of outage probability in multi intelligent reflecting surface assisted systems"
    - "cascaded channel estimation for large intelligent metasurface assisted massive mimo"
    - "enabling secure wireless communications via intelligent reflecting surfaces"
    - "weighted sum power maximization for intelligent reflecting surface aided swipt"
    - "intelligent reflecting surface enhanced wireless network via joint active and passive beamforming"
    - "reconfigurable intelligent surfaces for energy efficiency in wireless communication"
    - "large intelligent surface assisted wireless communication exploiting statistical csi"
    - "power efficient multi quality multicast beamforming based on scalable video coding and superposition coding"

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)