human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "articulated body dynamics simulation using optimization integrator"):
  Abstract: We present a novel optimization-based algorithm for articulated body dynamics simulation. We formulate the governing equations of rigid body dynamics using only the position variables and recast the position-based articulated dynamics as an optimization problem. We also extend our framework to handle joint limits, control forces/torques, fluid drag forces, and frictional contact forces. Our reformulation allows us to use an off-the-shelf optimization algorithm to time integrate the articulated body with an arbitrarily large timestep size and analyze the stability. Our algorithm can efficiently perform each iteration of optimization within $\mathcal{O}(N)$ time using Quasi-Newton method and $\mathcal{O}(N^2)$ time using Newton's method, where $N$ is the number of links. We highlight the performance on different benchmarks and compare the performance with prior articulated body dynamics simulators.

Includes members:
  Member "a linear time variational integrator for multibody systems":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "linear time variational integrators in maximal coordinates")
  Member "benchmarking deep reinforcement learning for continuous control":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "review analyze and design a comprehensive deep reinforcement learning framework")

Question: Please tell me which class the source paper 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.RO(Robotics)