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: "minimal inputs outputs for a networked system"
  Abstract: This letter investigates the minimal number of inputs/outputs required to guarantee system controllability/observability, under the condition that its state transition matrix (STM) is prescribed. A closed-form solution is derived. It has been proven that this minimal number is equal to the maximum geometric multiplicity of the STM, that is, the maximum of the dimensions of its eigenspaces. The obtained conclusions are in sharp contrast to those established for the problem of finding the sparest input/output matrix with a fixed number of inputs/outputs under the same restrictions. The latter has been proven to be NP-hard, and can only be approximated within a multiplicative factor. Moreover, a complete parametrization is also provided for the input/output matrix of a system with its number of inputs/outputs not smaller than this minimal value.

Connected through hyperedge HE-1 (induced by source paper "minimal reachability is hard to approximate"):
  with members:
    - "minimal reachability problems"
    - "variable selection is hard"
    - "minimizing convergence error in multi agent systems via leader selection a supermodular optimization approach"
    - "controllability metrics limitations and algorithms for complex networks"
    - "optimal approximation for submodular and supermodular optimization with bounded curvature"
    - "a supermodular optimization framework for leader selection under link noise in linear multi agent systems"

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)