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: "simulation vs equivalence"
  Abstract: For several semirings S, two weighted finite automata with multiplicities in S are equivalent if and only if they can be connected by a chain of simulations. Such a semiring S is called "proper". It is known that the Boolean semiring, the semiring of natural numbers, the ring of integers, all finite commutative positively ordered semirings and all fields are proper. The semiring S is Noetherian if every subsemimodule of a finitely generated S-semimodule is finitely generated. First, it is shown that all Noetherian semirings and thus all commutative rings and all finite semirings are proper. Second, the tropical semiring is shown not to be proper. So far there has not been any example of a semiring that is not proper.

Connected through hyperedge HE-1 (induced by source paper "proper semirings and proper convex functors"):
  with members:
    - "sound and complete axiomatizations of coalgebraic language equivalence"
    - "relating coalgebraic notions of bisimulation"
    - "a focused sequent calculus framework for proof search in pure type systems"

Connected through hyperedge HE-2 (induced by source paper "quantitative simulations by matrices"):
  with members:
    - "coalgebraic trace semantics via forgetful logics"
    - "coalgebraic infinite traces and kleisli simulations"
    - "coinduction up to in a fibrational setting"
    - "coalgebraic trace semantics for continuous probabilistic transition systems"
    - "sound and complete axiomatizations of coalgebraic language equivalence"
    - "computation of the greatest simulations and bisimulations between fuzzy automata"
    - "bisimulations for fuzzy automata"
    - "generic trace semantics via coinduction"

Connected through hyperedge HE-3 (induced by source paper "proper functors and fixed points for finite behaviour"):
  with members:
    - "semantics of higher order recursion schemes"
    - "free iterative and iteration k semialgebras"
    - "simulations of weighted tree automata"

Connected through hyperedge HE-4 (induced by source paper "sound and complete axiomatizations of coalgebraic language equivalence"):
  with members:
    - "semantics of higher order recursion schemes"
    - "non deterministic kleene coalgebras"
    - "free iterative and iteration k semialgebras"
    - "simulations of weighted tree automata"
    - "generic trace semantics via coinduction"

Connected through hyperedge HE-5 (induced by source paper "computation of the greatest simulations and bisimulations between fuzzy automata"):
  with members:
    - "construction of fuzzy automata from fuzzy regular expressions"
    - "bisimulations for fuzzy transition systems"
    - "bisimulations for fuzzy automata"
    - "reduction of fuzzy automata by means of fuzzy quasi orders"
    - "state based control of fuzzy discrete event systems"
    - "generalizing the paige tarjan algorithm by abstract interpretation"
    - "fuzzy discrete event systems under fuzzy observability and a test algorithm"
    - "supervisory control of fuzzy discrete event systems a formal approach"

Connected through hyperedge HE-6 (induced by source paper "bisimulations for fuzzy automata"):
  with members:
    - "reduction of fuzzy automata by means of fuzzy quasi orders"
    - "generalizing the paige tarjan algorithm by abstract interpretation"
    - "fuzzy discrete event systems under fuzzy observability and a test algorithm"
    - "supervisory control of fuzzy discrete event systems a formal approach"

Connected through hyperedge HE-7 (induced by source paper "free inductive k semialgebras"):
  with members:
    - "free iterative and iteration k semialgebras"
    - "partial conway and iteration semirings"

Connected through hyperedge HE-8 (induced by source paper "free iterative and iteration k semialgebras"):
  with members:
    - "partial conway and iteration semirings"

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.FL(Formal Languages and Automata Theory)