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: "resource allocation with subcarrier pairing in ofdma two way relay networks"
  Abstract: This study considers an orthogonal frequency-division multiple-access (OFDMA)-based multi-user two-way relay network where multiple mobile stations (MSs) communicate with a common base station (BS) via multiple relay stations (RSs). We study the joint optimization problem of subcarrier-pairing based relay-power allocation, relay selection, and subcarrier assignment. The problem is formulated as a mixed integer programming problem. By using the dual method, we propose an efficient algorithm to solve the problem in an asymptotically optimal manner. Simulation results show that the proposed method can improve system performance significantly over the conventional methods.

Connected through hyperedge HE-1 (induced by source paper "resource allocation and relay selection in full duplex cooperative orthogonal frequency division multiple access networks"):
  with members:
    - "on the uplink spectral efficiency of full duplex cooperative ofdma systems"
    - "full duplex radio for uplink downlink wireless access with spatially random nodes"
    - "on the spectral efficiency of full duplex small cell wireless systems"
    - "in band full duplex wireless challenges and opportunities"

Connected through hyperedge HE-2 (induced by source paper "energy harvesting for physical layer security in ofdma networks"):
  with members:
    - "secrecy wireless information and power transfer in fading wiretap channel"
    - "information and energy cooperation in ofdm relaying protocols and optimization"
    - "robust beamforming for secure communication in systems with wireless information and power transfer"
    - "secrecy wireless information and power transfer with miso beamforming"
    - "spatially selective artificial noise aided transmit optimization for miso multi eves secrecy rate maximization"
    - "simultaneous information and power transfer for broadband wireless systems"
    - "wireless information and power transfer in multiuser ofdm systems"
    - "wireless information and power transfer a dynamic power splitting approach"

Connected through hyperedge HE-3 (induced by source paper "energy harvesting for secure ofdma systems"):
  with members:
    - "simultaneous information and power transfer for broadband wireless systems"
    - "wireless information and power transfer in multiuser ofdm systems"
    - "wireless information and power transfer energy efficiency optimization in ofdma systems"
    - "wireless information and power transfer a dynamic power splitting approach"
    - "qos aware transmission policies for ofdm bidirectional decode and forward relaying"
    - "wireless information transfer with opportunistic energy harvesting"
    - "on the transfer of information and energy in multi user systems"
    - "power and subcarrier allocation for physical layer security in ofdma based broadband wireless networks"

Connected through hyperedge HE-4 (induced by source paper "spectrum leasing and cooperative resource allocation in cognitive ofdma networks"):
  with members:
    - "cross layer optimization of two way relaying for statistical qos guarantees"
    - "optimization framework and graph based approach for relay assisted bidirectional ofdma cellular networks"
    - "broadcast capacity region of two phase bidirectional relaying"
    - "physical network coding in two way wireless relay channels"

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)