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: "privacy optimal strategies for smart metering systems with a rechargeable battery"
  Abstract: In smart-metered systems, fine-grained power demand data (load profile) is communicated from a user to the utility provider. The correlation of the load profile with a user's private activities leaves open the possibility of inference attacks. Using a rechargeable battery, the user can partially obscure its load profile and provide some protection to the private information using various battery charging policies. Using the mutual information as the privacy metric we study a class of optimal battery charging policies. #R##N#When the power demand is a first-order Markov process, we propose a series of reductions on the optimization problem and ultimately recast it as a Markov decision process. In the special case of i.i.d. demand, we explicitly characterize the optimal policy and show that the associated privacy-leakage can be expressed as a single-letter mutual information expression.

Connected through hyperedge HE-1 (induced by source paper "privacy aware smart metering progress and challenges"):
  with members:
    - "optimal demand side management for joint privacy cost optimization with energy storage"
    - "smart meter privacy via the trapdoor channel"
    - "privacy protecting energy management unit through model distribution predictive control"
    - "information theoretic privacy for smart metering systems with a rechargeable battery"
    - "smart meter privacy with an energy harvesting device and instantaneous power constraints"
    - "the uk dale dataset domestic appliance level electricity demand and whole house demand from five uk homes"
    - "smart meter privacy for multiple users in the presence of an alternative energy source"
    - "increasing smart meter privacy through energy harvesting and storage devices"

Connected through hyperedge HE-2 (induced by source paper "smart meter privacy with renewable energy and a storage device"):
  with members:
    - "privacy protecting energy management unit through model distribution predictive control"
    - "sdp relaxation with randomized rounding for energy disaggregation"
    - "smart meter privacy with an energy harvesting device and instantaneous power constraints"
    - "smart meter privacy for multiple users in the presence of an alternative energy source"
    - "increasing smart meter privacy through energy harvesting and storage devices"

Connected through hyperedge HE-3 (induced by source paper "optimal demand side management for joint privacy cost optimization with energy storage"):
  with members:
    - "smart meter privacy with renewable energy and a storage device"
    - "the uk dale dataset domestic appliance level electricity demand and whole house demand from five uk homes"
    - "increasing smart meter privacy through energy harvesting and storage devices"

Connected through hyperedge HE-4 (induced by source paper "smart meter privacy with renewable energy and a finite capacity battery"):
  with members:
    - "smart meter privacy with an energy harvesting device and instantaneous power constraints"
    - "increasing smart meter privacy through energy harvesting and storage devices"
    - "the capacity of channels with feedback"

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)