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: "energy saving for building heating via a simple and efficient model free control design first steps with computer simulations"
  Abstract: The model-based control of building heating systems for energy saving encounters severe physical, mathematical and calibration difficulties in the numerous attempts that has been published until now. This topic is addressed here via a new model-free control setting, where the need of any mathematical description disappears. Several convincing computer simulations are presented. Comparisons with classic PI controllers and flatness-based predictive control are provided.

Connected through hyperedge HE-1 (induced by source paper "bullwhip effect attenuation in supply chain management via control theoretic tools and short term forecasts a preliminary study with an application to perishable inventories"):
  with members:
    - "la production de nitrites lors de la denitrification des eaux usees par biofiltration strategie de controle et de reduction des concentrations residuelles"
    - "an efficient model free setting for longitudinal and lateral vehicle control validation through the interconnected pro sivic rtmaps prototyping platform"
    - "an overview and comparative analysis of recurrent neural networks for short term load forecasting"
    - "non linear estimation is easy"

Connected through hyperedge HE-2 (induced by source paper "a simple but energy efficient hvac control synthesis for data centers"):
  with members:
    - "bullwhip effect attenuation in supply chain management via control theoretic tools and short term forecasts a preliminary study with an application to perishable inventories"

Connected through hyperedge HE-3 (induced by source paper "dynamic compensation and homeostasis a feedback control perspective"):
  with members:
    - "an efficient model free setting for longitudinal and lateral vehicle control validation through the interconnected pro sivic rtmaps prototyping platform"
    - "a simple and efficient feedback control strategy for wastewater denitrification"
    - "model based versus model free control designs for improving microalgae growth in a closed photobioreactor some preliminary comparisons"
    - "analyse non standard du bruit"

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)