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: "preserving lagrangian structure in nonlinear model reduction with application to structural dynamics"
  Abstract: This work proposes a model-reduction methodology that preserves Lagrangian structure and achieves computational efficiency in the presence of high-order nonlinearities and arbitrary parameter dependence. As such, the resulting reduced-order model retains key properties such as energy conservation and symplectic time-evolution maps. We focus on parameterized simple mechanical systems subjected to Rayleigh damping and external forces, and consider an application to nonlinear structural dynamics. To preserve structure, the method first approximates the system's “Lagrangian ingredients''---the Riemannian metric, the potential-energy function, the dissipation function, and the external force---and subsequently derives reduced-order equations of motion by applying the (forced) Euler--Lagrange equation with these quantities. From the algebraic perspective, key contributions include two efficient techniques for approximating parameterized reduced matrices while preserving symmetry and positive definiteness: matri...

Connected through hyperedge HE-1 (induced by source paper "pressio enabling projection based model reduction for large scale nonlinear dynamical systems"):
  with members:
    - "stability conditions for the explicit integration of projection based nonlinear reduced order and hyper reduced structural mechanics finite element models"
    - "model reduction of dynamical systems on nonlinear manifolds using deep convolutional autoencoders"
    - "conservative model reduction for finite volume models"
    - "space time least squares petrov galerkin projection for nonlinear model reduction"
    - "pymor generic algorithms and interfaces for model order reduction"
    - "occa a unified approach to multi threading languages"

Connected through hyperedge HE-2 (induced by source paper "conservative model reduction for finite volume models"):
  with members:
    - "space time least squares petrov galerkin projection for nonlinear model reduction"
    - "galerkin v least squares petrov galerkin projection in nonlinear model reduction"
    - "adaptive h refinement for reduced order models"
    - "two step greedy algorithm for reduced order quadratures"

Connected through hyperedge HE-3 (induced by source paper "galerkin v least squares petrov galerkin projection in nonlinear model reduction"):
  with members:
    - "two step greedy algorithm for reduced order quadratures"

Connected through hyperedge HE-4 (induced by source paper "galerkin v discrete optimal projection in nonlinear model reduction"):
  with members:
    - "two step greedy algorithm for reduced order quadratures"

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.CE(Computational Engineering, Finance, and Science)