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 applications the blockchain empowered software system"
  Abstract: Blockchain technology has attracted tremendous attention in both academia and capital market. However, overwhelming speculations on thousands of available cryptocurrencies and numerous initial coin offering scams have also brought notorious debates on this emerging technology. This paper traces the development of blockchain systems to reveal the importance of decentralized applications (dApps) and the future value of blockchain. We survey the state-of-the-art dApps and discuss the direction of blockchain development to fulfill the desirable characteristics of dApps. The readers will gain an overview of dApp research and get familiar with recent developments in the blockchain.

Connected through hyperedge HE-1 (induced by source paper "testimonium a cost efficient blockchain relay"):
  with members:
    - "cross chain deals and adversarial commerce"
    - "blockchain based data provenance for the internet of things"
    - "atomic cross chain swaps"

Connected through hyperedge HE-2 (induced by source paper "towards the uses of blockchain in mobile health services and applications a survey"):
  with members:
    - "controlling robots using artificial intelligence and a consortium blockchain"
    - "a scalable verification solution for blockchains"
    - "an overview of blockchain integration with robotics and artificial intelligence"
    - "a microservice enabled architecture for smart surveillance using blockchain technology"
    - "a survey on the security of blockchain systems"
    - "blockchain and artificial intelligence"
    - "blockchain for cities a systematic literature review"
    - "secure outsourced calculations with homomorphic encryption"

Connected through hyperedge HE-3 (induced by source paper "pnyxdb a lightweight leaderless democratic byzantine fault tolerant replicated datastore"):
  with members:
    - "scalable and probabilistic leaderless bft consensus through metastability"
    - "flexible byzantine fault tolerance"
    - "streamchain do blockchains need blocks"
    - "hyperledger fabric a distributed operating system for permissioned blockchains"
    - "consensus in the age of blockchains"
    - "a byzantine fault tolerant ordering service for the hyperledger fabric blockchain platform"
    - "exploiting commutativity for practical fast replication"
    - "hardening cassandra against byzantine failures"

Connected through hyperedge HE-4 (induced by source paper "blockchain based access control systems state of the art and challenges"):
  with members:
    - "verifiable anonymous identities and access control in permissioned blockchains"
    - "distributed access control with blockchain"
    - "physical access control management system based on permissioned blockchain"
    - "medichain tm a secure decentralized medical data asset management system"
    - "an efficient framework for optimistic concurrent execution of smart contracts"
    - "adding concurrency to smart contracts"

Connected through hyperedge HE-5 (induced by source paper "likestarter a smart contract based social dao for crowdfunding"):
  with members:
    - "the ico phenomenon and its relationships with ethereum smart contract environment"
    - "a blockchain based flight data recorder for cloud accountability"
    - "highly intensive data dissemination in complex networks"

Connected through hyperedge HE-6 (induced by source paper "a security case study for blockchain games"):
  with members:
    - "blockchain games a survey"
    - "finding the greedy prodigal and suicidal contracts at scale"

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.DC(Distributed, Parallel, and Cluster Computing)