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: "hybrid radio free space optical design for next generation backhaul systems"
  Abstract: The deluge of date rate in today's networks imposes a cost burden on the backhaul network design. Developing cost efficient backhaul solutions becomes an exciting, yet challenging, problem. Traditional technologies for backhaul networks include either radio-frequency backhauls (RF) or optical fibers (OF). While RF is a cost-effective solution as compared to OF, it supports lower data rate requirements. Another promising backhaul solution is the free-space optics (FSO) as it offers both a high data rate and a relatively low cost. FSO, however, is sensitive to nature conditions, e.g., rain, fog, line-of-sight. This paper combines both RF and FSO advantages and proposes a hybrid RF/FSO backhaul solution. It considers the problem of minimizing the cost of the backhaul network by choosing either OF or hybrid RF/FSO backhaul links between the base-stations (BS) so as to satisfy data rate, connectivity, and reliability constraints. It shows that under a specified realistic assumption about the cost of OF and hybrid RF/FSO links, the problem is equivalent to a maximum weight clique problem, which can be solved with moderate complexity. Simulation results show that the proposed solution shows a close-to-optimal performance, especially for practical prices of the hybrid RF/FSO links.

Connected through hyperedge HE-1 (induced by source paper "6g wireless communication systems applications requirements technologies challenges and research directions"):
  with members:
    - "towards 6g networks use cases and technologies"
    - "blockchain for internet of things a survey"
    - "uav communications for 5g and beyond recent advances and future trends"
    - "a vision of 6g wireless systems applications trends technologies and open research problems"
    - "on the effect of temporal correlation on joint success probability and distribution of number of interferers in mobile uav networks"
    - "six key enablers for machine type communication in 6g"
    - "integrated rf optical wireless networks for improving qos in indoor and transportation applications"
    - "a speculative study on 6g"

Connected through hyperedge HE-2 (induced by source paper "a tutorial on clique problems in communications and signal processing"):
  with members:
    - "eptas for max clique on disks and unit balls"
    - "enhanced uplink resource allocation in non orthogonal multiple access systems"
    - "discovering patterns of interest in ip traffic using cliques in bipartite link streams"
    - "delivery time reduction for order constrained applications using binary network codes"
    - "data dissemination using instantly decodable binary codes in fog radio access networks"
    - "on multiaspect graphs"
    - "distributed hybrid scheduling in multi cloud networks using conflict graphs"
    - "resilient backhaul network design using hybrid radio free space optical technology"

Connected through hyperedge HE-3 (induced by source paper "c ran with hybrid rf fso fronthaul links joint optimization of rf time allocation and fronthaul compression"):
  with members:
    - "on the design of matched filters for molecule counting receivers"
    - "on the optimal fronthaul compression and decoding strategies for uplink cloud radio access networks"
    - "recent advances in cloud radio access networks system architectures key techniques and open issues"
    - "optimal relay selection for the parallel hybrid rf fso relay channel non buffer aided and buffer aided designs"
    - "fronthaul compression and transmit beamforming optimization for multi antenna uplink c ran"
    - "fronthaul constrained cloud radio access networks insights and challenges"
    - "optimized backhaul compression for uplink cloud radio access network"
    - "on the capacity of free space optical intensity channels"

Connected through hyperedge HE-4 (induced by source paper "optimal relay selection for the parallel hybrid rf fso relay channel non buffer aided and buffer aided designs"):
  with members:
    - "optical communication in space challenges and mitigation techniques"
    - "achievable rates for the fading half duplex single relay selection network using buffer aided relaying"
    - "achievable rate region of the bidirectional buffer aided relay channel with block fading"
    - "statistical delay tradeoffs in buffer aided two hop wireless communication systems"
    - "experiment driven characterization of full duplex wireless systems"
    - "a simple cooperative diversity method based on network path selection"

Connected through hyperedge HE-5 (induced by source paper "resilient backhaul network design using hybrid radio free space optical technology"):
  with members:
    - "coordinated scheduling for the downlink of cloud radio access networks"
    - "what will 5g be"

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)