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: "sparse attack construction and state estimation in the smart grid centralized and distributed models"
  Abstract: New methods that exploit sparse structures arising in smart grid networks are proposed for the state estimation problem when data injection attacks are present. First, construction strategies for unobservable sparse data injection attacks on power grids are proposed for an attacker with access to all network information and nodes. Specifically, novel formulations for the optimization problem that provide a flexible design of the trade-off between performance and false alarm are proposed. In addition, the centralized case is extended to a distributed framework for both the estimation and attack problems. Different distributed scenarios are proposed depending on assumptions that lead to the spreading of the resources, network nodes and players. Consequently, for each of the presented frameworks a corresponding optimization problem is introduced jointly with an algorithm to solve it. The validity of the presented procedures in real settings is studied through extensive simulations in the IEEE test systems.

Connected through hyperedge HE-1 (induced by source paper "data driven false data injection attacks against power grid a random matrix approach"):
  with members:
    - "subspace methods for data attack on state estimation a data driven approach"

Connected through hyperedge HE-2 (induced by source paper "state of the art of cyber physical systems security an automatic control perspective"):
  with members:
    - "on redundant observability from security index to attack detection and resilient state estimation"
    - "detection of sensor attack and resilient state estimation for uniformly observable nonlinear systems having redundant sensors"
    - "analysis of stochastic switched systems with application to networked control under jamming attacks"
    - "coding schemes for securing cyber physical systems against stealthy data injection attacks"
    - "detecting integrity attacks on control systems using a moving target approach"
    - "a moving horizon hybrid stochastic game for secure control of cyber physical systems"
    - "modeling and performance evaluation of stealthy false data injection attacks on smart grid in the presence of corrupted measurements"
    - "state estimation with secrecy against eavesdroppers"

Connected through hyperedge HE-3 (induced by source paper "learning requirements for stealth attacks"):
  with members:
    - "stealth attacks on the smart grid"
    - "information theoretic attacks in the smart grid"
    - "effective secrecy reliability confusion and stealth"

Connected through hyperedge HE-4 (induced by source paper "smart grid cyber attacks detection using supervised learning and heuristic feature selection"):
  with members:
    - "machine learning methods for attack detection in the smart grid"

Connected through hyperedge HE-5 (induced by source paper "stealth attacks on the smart grid"):
  with members:
    - "smart meter privacy via the trapdoor channel"
    - "information theoretic attacks in the smart grid"
    - "increasing smart meter privacy through energy harvesting and storage devices"
    - "effective secrecy reliability confusion and stealth"

Connected through hyperedge HE-6 (induced by source paper "modeling and performance evaluation of stealthy false data injection attacks on smart grid in the presence of corrupted measurements"):
  with members:
    - "subspace methods for data attack on state estimation a data driven approach"
    - "data framing attack on state estimation"
    - "vulnerabilities of smart grid state estimation against false data injection attack"
    - "robust principal component analysis"

Connected through hyperedge HE-7 (induced by source paper "robust recovery of missing data in electricity distribution systems"):
  with members:
    - "the power of convex relaxation near optimal matrix completion"
    - "matrix completion with noise"
    - "exact matrix completion via convex optimization"

Connected through hyperedge HE-8 (induced by source paper "information theoretic attacks in the smart grid"):
  with members:
    - "smart meter privacy via the trapdoor channel"
    - "increasing smart meter privacy through energy harvesting and storage devices"
    - "effective secrecy reliability confusion and stealth"

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.IT(Information Theory)