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: "review of blockchain technology and its expectations case of the energy sector"
  Abstract: This article suggests that the worldwide relevance of blockchain technology is motivated by the changes that it is expected to cause in: (i) the way that business is organised and (ii) regulated, as well as (iii) by the way that it changes the role of individuals within a society. The article presents an overview of the features of blockchain technology. It then takes a closer look into the developments within the energy sector across the world to gain a preliminary indication of whether the stated expectations are coming to reality. As a result of this review, we remain cautiously optimistic that blockchain technology could deliver the expected impact.

Connected through hyperedge HE-1 (induced by source paper "blockchain applications in power systems a bibliometric analysis"):
  with members:
    - "integrating privacy enhancing techniques into blockchains using sidechains"
    - "smart grid cyber attacks detection using supervised learning and heuristic feature selection"
    - "a secure and efficient direct power load control framework based on blockchain"
    - "the journal coverage of web of science and scopus a comparative analysis"
    - "network function virtualization state of the art and research challenges"

Connected through hyperedge HE-2 (induced by source paper "towards secure blockchain enabled internet of vehicles optimizing consensus management using reputation and contract theory"):
  with members:
    - "a survey on consensus mechanisms and mining strategy management in blockchain networks"
    - "speedychain a framework for decoupling data from blockchain for smart cities"
    - "incentive mechanism design for wireless energy harvesting based internet of things"
    - "intelligent vehicle trust point reward based intelligent vehicle communication using blockchain"
    - "evolutionary game for mining pool selection in blockchain networks"
    - "blockchain based intelligent vehicle data sharing framework"
    - "decentralized computation offloading game for mobile cloud computing"

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.CY(Computers and Society)