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: "on the spectral efficiency of full duplex small cell wireless systems"
  Abstract: We investigate the spectral efficiency of full-duplex small cell wireless systems, in which a full-duplex capable base station (BS) is designed to send/receive data to/from multiple half-duplex users on the same system resources. The major hurdle for designing such systems is due to the self-interference at the BS and co-channel interference among users. Hence, we consider a joint beamformer design to maximize the spectral efficiency subject to certain power constraints. The design problem is first formulated as a rank-constrained optimization problem, and the rank relaxation method is then applied. However, the relaxed problem is still nonconvex, and thus, optimal solutions are hard to find. Herein, we propose two provably convergent algorithms to obtain suboptimal solutions. Based on the concept of the Frank-Wolfe algorithm, we approximate the design problem by a determinant maximization program in each iteration of the first algorithm. The second method is built upon the sequential parametric convex approximation method, which allows us to transform the relaxed problem into a semidefinite program in each iteration. Extensive numerical experiments under small cell setups illustrate that the full-duplex system with the proposed algorithms can achieve a large gain over the half-duplex system.

Connected through hyperedge HE-1 (induced by source paper "optimal centralized dynamic time division duplex"):
  with members:
    - "user selection and power allocation in full duplex multicell networks"
    - "d2d enhanced heterogeneous cellular networks with dynamic tdd"
    - "interference spins scheduling of multiple interfering two way wireless links"

Connected through hyperedge HE-2 (induced by source paper "joint sparse beamforming and power control for large scale das with network assistant full duplex"):
  with members:
    - "performance of network assisted full duplex for cell free massive mimo"
    - "fractional programming for communication systems part ii uplink scheduling via matching"
    - "cross layer design for downlink multihop cloud radio access networks with network coding"
    - "analysis of massive mimo enabled downlink wireless backhauling for full duplex small cells"
    - "energy efficiency of downlink transmission strategies for cloud radio access networks"
    - "d2d enhanced heterogeneous cellular networks with dynamic tdd"
    - "compflex comp for in band wireless full duplex"
    - "sparse beamforming and user centric clustering for downlink cloud radio access network"

Connected through hyperedge HE-3 (induced by source paper "dynamic time frequency division duplex"):
  with members:
    - "user selection and power allocation in full duplex multicell networks"
    - "why to decouple the uplink and downlink in cellular networks and how to do it"
    - "interference spins scheduling of multiple interfering two way wireless links"
    - "multi objective optimization for robust power efficient and secure full duplex wireless communication systems"
    - "analysis of the decoupled access for downlink and uplink in wireless heterogeneous networks"

Connected through hyperedge HE-4 (induced by source paper "a new design paradigm for secure full duplex multiuser systems"):
  with members:
    - "secure transmission with large numbers of antennas and finite alphabet inputs"
    - "exploiting full duplex receivers for achieving secret communications in multiuser miso networks"
    - "joint fractional time allocation and beamforming for downlink multiuser miso systems"
    - "secure massive mimo transmission with an active eavesdropper"
    - "a general mimo framework for noma downlink and uplink transmission based on signal alignment"
    - "multi objective optimization for robust power efficient and secure full duplex wireless communication systems"
    - "robust beamforming for secure communication in systems with wireless information and power transfer"
    - "secrecy wireless information and power transfer with miso beamforming"

Connected through hyperedge HE-5 (induced by source paper "is self interference in full duplex communications a foe or a friend"):
  with members:
    - "energy efficient power control a look at 5g wireless technologies"
    - "wireless powered communication opportunities and challenges"
    - "energy recycling full duplex radios for next generation networks"
    - "full duplex wireless powered relay with self energy recycling"
    - "wireless information and power transfer with full duplex relaying"
    - "fast converging algorithm for weighted sum rate maximization in multicell miso downlink"
    - "robust monotonic optimization framework for multicell miso systems"

Connected through hyperedge HE-6 (induced by source paper "how to split ul dl antennas in full duplex cellular networks"):
  with members:
    - "softnull many antenna full duplex wireless via digital beamforming"
    - "design and characterization of a full duplex multiantenna system for wifi networks"
    - "in band full duplex wireless challenges and opportunities"
    - "experiment driven characterization of full duplex wireless systems"

Connected through hyperedge HE-7 (induced by source paper "fundamental green tradeoffs progresses challenges and impacts on 5g networks"):
  with members:
    - "spectrum power trading for energy efficient small cell"
    - "power efficient resource allocation for full duplex radio distributed antenna networks"
    - "energy recycling full duplex radios for next generation networks"
    - "energy efficient resource allocation for wireless powered communication networks"
    - "multi objective optimization for robust power efficient and secure full duplex wireless communication systems"
    - "hybrid millimeter wave systems a novel paradigm for hetnets"
    - "coexistence of wi fi and heterogeneous small cell networks sharing unlicensed spectrum"
    - "filter bank multicarrier for massive mimo"

Connected through hyperedge HE-8 (induced by source paper "interference exploitation in full duplex communications trading interference power for both uplink and downlink power savings"):
  with members:
    - "probabilistically robust swipt for secrecy misome systems"
    - "unraveling the rank one solution mystery of robust miso downlink transmit optimization a verifiable sufficient condition via a new duality result"
    - "transmit precoding for interference exploitation in the underlay cognitive radio z channel"
    - "energy efficient symbol level precoding in multiuser miso based on relaxed detection region"
    - "symbol level multiuser miso precoding for multi level adaptive modulation"
    - "multi objective resource allocation in full duplex swipt systems"
    - "constructive interference through symbol level precoding for multi level modulation"
    - "constructive multiuser interference in symbol level precoding for the miso downlink channel"

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)