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: "on and off blockchain enforcement of smart contracts"
  Abstract: In this paper we discuss how conventional business contracts can be converted into smart contracts---their electronic equivalents that can be used to systematically monitor and enforce contractual rights, obligations and prohibitions at run time. We explain that emerging blockchain technology is certainly a promising platform for implementing smart contracts but argue that there is a large class of applications, where blockchain is inadequate due to performance, scalability, and consistency requirements, and also due to language expressiveness and cost issues that are hard to solve. We explain that in some situations a centralised approach that does not rely on blockchain is a better alternative due to its simplicity, scalability, and performance. We suggest that in applications where decentralisation and transparency are essential, developers can advantageously combine the two approaches into hybrid solutions where some operations are enforced by enforcers deployed on--blockchains and the rest by enforcers deployed on trusted third parties.

Connected through hyperedge HE-1 (induced by source paper "user acceptance of usable blockchain based research data sharing system an extended tam based study"):
  with members:
    - "user data sharing frameworks a blockchain based incentive solution"
    - "user controlled privacy preserving user profile data sharing based on blockchain"
    - "performance analysis and application of mobile blockchain"

Connected through hyperedge HE-2 (induced by source paper "user data sharing frameworks a blockchain based incentive solution"):
  with members:
    - "user controlled privacy preserving user profile data sharing based on blockchain"
    - "blockchain based smart contracts a systematic mapping study"

Connected through hyperedge HE-3 (induced by source paper "implementation of smart contracts using hybrid architectures with on and off blockchain components"):
  with members:
    - "scilla a smart contract intermediate level language"
    - "towards a design philosophy for interoperable blockchain systems"
    - "designing secure ethereum smart contracts a finite state machine based approach"
    - "runtime verification for business processes utilizing the bitcoin blockchain"
    - "optimized execution of business processes on blockchain"
    - "enigma decentralized computation platform with guaranteed privacy"
    - "when money learns to fly towards sensing as a service applications using bitcoin"

Connected through hyperedge HE-4 (induced by source paper "end to end service level agreement specification for iot applications"):
  with members:
    - "fog computing a taxonomy survey and future directions"
    - "implementation of smart contracts using hybrid architectures with on and off blockchain components"

Connected through hyperedge HE-5 (induced by source paper "demonstration abstract a toolkit for specifying service level agreements for iot applications"):
  with members:
    - "implementation of smart contracts using hybrid architectures with on and off blockchain components"

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)