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: "on structured realizability and stabilizability of linear systems"
  Abstract: We study the notion of structured realizability for linear systems defined over graphs. A stabilizable and detectable realization is structured if the state-space matrices inherit the sparsity pattern of the adjacency matrix of the associated graph. In this paper, we demonstrate that not every structured transfer matrix has a structured realization and we reveal the practical meaning of this fact. We also uncover a close connection between the structured realizability of a plant and whether the plant can be stabilized by a structured controller. In particular, we show that a structured stabilizing controller can only exist when the plant admits a structured realization. Finally, we give a parameterization of all structured stabilizing controllers and show that they always have structured realizations.

Connected through hyperedge HE-1 (induced by source paper "optimal control of two player systems with output feedback"):
  with members:
    - "optimal control strategies in delayed sharing information structures"

Connected through hyperedge HE-2 (induced by source paper "state space solution to a minimum entropy mathcal h _ infty optimal control problem with a nested information constraint"):
  with members:
    - "optimal control of two player systems with output feedback"

Connected through hyperedge HE-3 (induced by source paper "optimal decentralized state feedback control with sparsity and delays"):
  with members:
    - "optimal control of two player systems with output feedback"
    - "structural results and explicit solution for two player lqg systems on a finite time horizon"
    - "output feedback h_2 model matching for decentralized systems with delays"
    - "optimal control strategies in delayed sharing information structures"

Connected through hyperedge HE-4 (induced by source paper "the h2 control problem for quadratically invariant systems with delays"):
  with members:
    - "distributed output feedback lqg control with delayed information sharing"
    - "decentralized stochastic control with partial history sharing a common information approach"
    - "output feedback h_2 model matching for decentralized systems with delays"
    - "optimal control strategies in delayed sharing information structures"

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)