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: "the coarsest precongruences respecting safety and liveness properties"
  Abstract: This paper characterises the coarsest refinement preorders on labelled transition systems that are precongruences for renaming and partially synchronous interleaving operators, and respect all safety, liveness, and conditional liveness properties, respectively.

Connected through hyperedge HE-1 (induced by source paper "failure trace semantics for a process algebra with time outs preliminary report"):
  with members:
    - "ensuring liveness properties of distributed systems open problems"
    - "a theory of encodings and expressiveness"
    - "lean and full congruence formats for recursion"

Connected through hyperedge HE-2 (induced by source paper "ensuring liveness properties of distributed systems open problems"):
  with members:
    - "progress justness and fairness"
    - "reward testing equivalences for processes"
    - "justness a completeness criterion for capturing liveness properties"
    - "analysing mutual exclusion using process algebra with signals"
    - "lean and full congruence formats for recursion"
    - "structure preserving bisimilarity supporting an operational petri net semantics of ccsp"
    - "ccs it s not fair fair schedulers cannot be implemented in ccs like languages even under progress and certain fairness assumptions"
    - "progress fairness and justness in process algebra"

Connected through hyperedge HE-3 (induced by source paper "reward testing equivalences for processes"):
  with members:
    - "lean and full congruence formats for recursion"
    - "ensuring liveness properties of distributed systems a research agenda"
    - "progress fairness and justness in process algebra"
    - "on the axiomatizability of impossible futures"
    - "characterising testing preorders for finite probabilistic processes"

Connected through hyperedge HE-4 (induced by source paper "all linear time congruences for familiar operators"):
  with members:
    - "congruence from the operator s point of view compositionality requirements on process semantics"

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)