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: "asynchronous source clock frequency recovery through aperiodic packet streams"
  Abstract: We consider the most general case of source clock frequency recovery (SCFR) in packet networks, i.e., asynchronous SCFR through aperiodic packet streams, where there is neither a common reference clock nor any relation between packet generation intervals and a source clock frequency. We formulate the problem of asynchronous SCFR with timestamps as a linear case of regression through the origin (RTO) and propose two schemes, one based on recursive least squares (RLS) method and the other based on simple heuristics of cumulative ratio of interarrival and interdeparture times, which provide better estimates of the source clock frequency with faster convergence than conventional phase-locked loop (PLL)-based schemes.

Connected through hyperedge HE-1 (induced by source paper "a beaconless asymmetric energy efficient time synchronization scheme for resource constrained multi hop wireless sensor networks"):
  with members:
    - "on the practical implementation of propagation delay and clock skew compensated high precision time synchronization schemes with resource constrained sensor nodes in multi hop wireless sensor networks"
    - "energy efficient time synchronization based on asynchronous source clock frequency recovery and reverse two way message exchanges in wireless sensor networks"
    - "analysis study of time synchronization protocols in wireless sensor networks"

Connected through hyperedge HE-2 (induced by source paper "on the practical implementation of propagation delay and clock skew compensated high precision time synchronization schemes with resource constrained sensor nodes in multi hop wireless sensor networks"):
  with members:
    - "energy efficient time synchronization based on asynchronous source clock frequency recovery and reverse two way message exchanges in wireless sensor networks"
    - "efficient single hop time synchronization protocol for randomly connected wsns"

Connected through hyperedge HE-3 (induced by source paper "energy efficient time synchronization based on asynchronous source clock frequency recovery and reverse two way message exchanges in wireless sensor networks"):
  with members:
    - "experimental demonstration of nanosecond accuracy wireless network synchronization"
    - "comments on ieee 1588 clock synchronization using dual slave clocks in a slave"

Connected through hyperedge HE-4 (induced by source paper "simulation study of an energy efficient time synchronization scheme based on source clock frequency recovery in asymmetric wireless sensor networks"):
  with members:
    - "comments on ieee 1588 clock synchronization using dual slave clocks in a slave"

Connected through hyperedge HE-5 (induced by source paper "on the multi hop extension of energy efficient wsn time synchronization based on time translating gateways"):
  with members:
    - "simulation study of an energy efficient time synchronization scheme based on source clock frequency recovery in asymmetric wireless sensor networks"

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)