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: "unifying theories of reactive design contracts"
  Abstract: Design-by-contract is an important technique for model-based design in which a composite system is specified by a collection of contracts that specify the behavioural assumptions and guarantees of each component. In this paper, we describe a unifying theory for reactive design contracts that provides the basis for modelling and verification of reactive systems. We provide a language for expression and composition of contracts that is supported by a rich calculational theory. In contrast with other semantic models in the literature, our theory of contracts allow us to specify both the evolution of state variables and the permissible interactions with the environment. Moreover, our model of interaction is abstract, and supports, for instance, discrete time, continuous time, and hybrid computational models. Being based in Unifying Theories of Programming (UTP), our theory can be composed with further computational theories to support semantics for multi-paradigm languages. Practical reasoning support is provided via our proof framework, Isabelle/UTP, including a proof tactic that reduces a conjecture about a reactive program to three predicates, characterising its assumptions and guarantees about intermediate and final observations. Our work advances the state-of-the-art in semantics for reactive languages, description of their contractual specifications, and compositional verification.

Connected through hyperedge HE-1 (induced by source paper "unifying semantic foundations for automated verification tools in isabelle utp"):
  with members:
    - "differential hoare logics and refinement calculi for hybrid systems with isabelle hol"
    - "calculational verification of reactive programs with reactive relations and kleene algebra"
    - "automating verification of state machines with reactive designs and isabelle utp"
    - "unifying theories of time with generalised reactive processes"
    - "robotics and integrated formal methods necessity meets opportunity"
    - "profunctor optics modular data accessors"

Connected through hyperedge HE-2 (induced by source paper "calculational verification of reactive programs with reactive relations and kleene algebra"):
  with members:
    - "unifying theories of time with generalised reactive processes"
    - "the refinement calculus of reactive systems"

Connected through hyperedge HE-3 (induced by source paper "automating verification of state machines with reactive designs and isabelle utp"):
  with members:
    - "calculational verification of reactive programs with reactive relations and kleene algebra"
    - "unifying theories of time with generalised reactive processes"

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.LO(Logic in Computer Science)