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: "decentralized control problems with substitutable actions"
  Abstract: We consider a decentralized system with multiple controllers and define substitutability of one controller by another in open-loop strategies. We explore the implications of this property on the optimization of closed-loop strategies. In particular, we focus on the decentralized LQG problem with substitutable actions. Even though the problem we formulate does not belong to the known classes of "simpler" decentralized problems such as partially nested or quadratically invariant problems, our results show that, under the substitutability assumption, linear strategies are optimal and we provide a complete state space characterization of optimal strategies. We also identify a family of information structures that all give the same optimal cost as the centralized information structure under the substitutability assumption. Our results suggest that open-loop substitutability can work as a counterpart of the information structure requirements that enable simplification of decentralized control problems.

Connected through hyperedge HE-1 (induced by source paper "optimal infinite horizon decentralized networked controllers with unreliable communication"):
  with members:
    - "optimal local and remote controllers with unreliable uplink channels"
    - "dynamic teams and decentralized control problems with substitutable actions"
    - "optimal local and remote controllers with unreliable communication"
    - "optimal control of two player systems with output feedback"
    - "optimal control for lqg systems on graphs part i structural results"
    - "optimal decentralized state feedback control with sparsity and delays"
    - "distributed output feedback lqg control with delayed information sharing"
    - "decentralized stochastic control with partial history sharing a common information approach"

Connected through hyperedge HE-2 (induced by source paper "decentralized control of stochastically switched linear system with unreliable communication"):
  with members:
    - "optimal local and remote controllers with unreliable uplink channels"
    - "dynamic teams and decentralized control problems with substitutable actions"
    - "optimal local and remote controllers with unreliable communication"
    - "optimal control of two player systems with output feedback"
    - "structural results and explicit solution for two player lqg systems on a finite time horizon"
    - "decentralized stochastic control with partial history sharing a common information approach"

Connected through hyperedge HE-3 (induced by source paper "optimal local and remote controllers with unreliable uplink channels"):
  with members:
    - "dynamic teams and decentralized control problems with substitutable actions"
    - "optimal local and remote controllers with unreliable communication"
    - "optimal control of two player systems with output feedback"
    - "structural results and explicit solution for two player lqg systems on a finite time horizon"
    - "decentralized stochastic control with partial history sharing a common information approach"
    - "optimal strategies for communication and remote estimation with an energy harvesting sensor"
    - "optimal decentralized control of coupled subsystems with control sharing"

Connected through hyperedge HE-4 (induced by source paper "team optimal decentralized control of system with partially exchangeable agents part 1 linear quadratic mean field teams"):
  with members:
    - "the iso problem decentralized stochastic control via bidding schemes"
    - "optimal control of two player systems with output feedback"
    - "signaling for decentralized routing in a queueing network"
    - "distributed control with low rank coordination"
    - "the complexity of decentralized control of markov decision processes"

Connected through hyperedge HE-5 (induced by source paper "optimal local and remote controllers with unreliable communication"):
  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"
    - "decentralized stochastic control with partial history sharing a common information approach"
    - "optimal strategies for communication and remote estimation with an energy harvesting sensor"

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)