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: "contraction analysis of switched systems via regularization"
  Abstract: We study incremental stability and convergence of switched (bimodal) Filippov systems via contraction analysis. In particular, by using results on regularization of switched dynamical systems, we derive sufficient conditions for convergence of any two trajectories of the Filippov system between each other within some region of interest. We then apply these conditions to the study of different classes of Filippov systems including piecewise smooth (PWS) systems, piecewise affine (PWA) systems and relay feedback systems. We show that contrary to previous approaches, our conditions allow the system to be studied in metrics other than the Euclidean norm. The theoretical results are illustrated by numerical simulations on a set of representative examples that confirm their effectiveness and ease of application.

Connected through hyperedge HE-1 (induced by source paper "robust contraction analysis of nonlinear systems via differential iqc"):
  with members:
    - "control contraction metrics convex and intrinsic criteria for nonlinear feedback design"
    - "on differentially dissipative dynamical systems"
    - "a differential lyapunov framework for contraction analysis"

Connected through hyperedge HE-2 (induced by source paper "control contraction metrics on finsler manifolds"):
  with members:
    - "on existence of separable contraction metrics for monotone nonlinear systems"
    - "nonlinear stabilization via control contraction metrics a pseudospectral approach for computing geodesics"
    - "control contraction metrics convex and intrinsic criteria for nonlinear feedback design"
    - "a differential lyapunov framework for contraction analysis"
    - "logarithmic lipschitz norms and diffusion induced instability"

Connected through hyperedge HE-3 (induced by source paper "observer design for piecewise smooth and switched systems via contraction theory"):
  with members:
    - "switching control for incremental stabilization of nonlinear systems via contraction theory"
    - "a differential lyapunov framework for contraction analysis"

Connected through hyperedge HE-4 (induced by source paper "switching control for incremental stabilization of nonlinear systems via contraction theory"):
  with members:
    - "a differential lyapunov framework for contraction analysis"

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.SY(Systems and Control)