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: "integrated rf optical wireless networks for improving qos in indoor and transportation applications"
  Abstract: Communications based solely on radio frequency (RF) networks cannot provide adequate quality of service for the rapidly growing demands of wireless connectivity. Since devices operating in the optical spectrum do not interfere with those using the RF spectrum, wireless networks based on the optical spectrum can be added to existing RF networks to fulfill this demand. Hence, optical wireless communication (OWC) technology can be an excellent complement to RF-based technology to provide improved service. Promising OWC systems include light fidelity (LiFi), visible light communication, optical camera communication (OCC), and free-space optical communication (FSOC). OWC and RF systems have differing limitations, and the integration of RF and optical wireless networks can overcome the limitations of both systems. This paper describes an LiFi/femtocell hybrid network system for indoor environments. Low signal-to-interference-plus-noise ratios and the shortage bandwidth problems of existing RF femtocell networks can be overcome with the proposed hybrid model. Moreover, we describe an integrated RF/optical wireless system that can be employed for users inside a vehicle, remote monitoring of ambulance patients, vehicle tracking, and vehicle-to-vehicle communications. We consider LiFi, OCC, and FSOC as the optical wireless technologies to be used for communication support in transportation, and assume macrocells, femtocells, and wireless fidelity to be the corresponding RF technologies. We describe handover management—including detailed call flow, interference management, link reliability improvement, and group handover provisioning—for integrated networks. Performance analyses demonstrate the significance of the proposed integrated RF/optical wireless systems.

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"
    - "a speculative study on 6g"
    - "6g the wireless communications network for collaborative and ai applications"

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.NI(Networking and Internet Architecture)