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: "detecting unrealizability of distributed fault tolerant systems"
  Abstract: Writing formal specifications for distributed systems is difficult. Even#N#simple consistency requirements often turn out to be unrealizable because of#N#the complicated information flow in the distributed system: not all information#N#is available in every component, and information transmitted from other#N#components may arrive with a delay or not at all, especially in the presence of#N#faults. The problem of checking the distributed realizability of a temporal#N#specification is, in general, undecidable. Semi-algorithms for synthesis, such#N#as bounded synthesis, are only useful in the positive case, where they#N#construct an implementation for a realizable specification, but not in the#N#negative case: if the specification is unrealizable, the search for the#N#implementation never terminates. In this paper, we introduce counterexamples to#N#distributed realizability and present a method for the detection of such#N#counterexamples for specifications given in linear-time temporal logic (LTL). A#N#counterexample consists of a set of paths, each representing a different#N#sequence of inputs from the environment, such that, no matter how the#N#components are implemented, the specification is violated on at least one of#N#these paths. We present a method for finding such counterexamples both for the#N#classic distributed realizability problem and for the fault-tolerant#N#realizability problem. Our method considers, incrementally, larger and larger#N#sets of paths until a counterexample is found. For safety specifications in#N#weakly ordered architectures we obtain a decision procedure, while#N#counterexamples for full LTL and arbitrary architectures may consist of#N#infinitely many paths. Experimental results, obtained with a QBF-based#N#prototype implementation, show that our method finds simple errors very#N#quickly, and even problems with high combinatorial complexity, like the#N#Byzantine Generals' Problem, are tractable.

Connected through hyperedge HE-1 (induced by source paper "the challenges in specifying and explaining synthesized implementations of reactive systems"):
  with members:
    - "bosy an experimentation framework for bounded synthesis"
    - "synthesizing skeletons for reactive systems"
    - "strategy representation by decision trees in reactive synthesis"
    - "reactive synthesis towards output sensitive algorithms"
    - "the 4th reactive synthesis competition syntcomp 2017 benchmarks participants results"
    - "bounded cycle synthesis"
    - "structural synthesis for gxw specifications"
    - "counterexample explanation by learning small strategies in markov decision processes"

Connected through hyperedge HE-2 (induced by source paper "synthesizing reactive systems from hyperproperties"):
  with members:
    - "bosy an experimentation framework for bounded synthesis"
    - "monitoring hyperproperties"
    - "encodings of bounded synthesis"
    - "the first order logic of hyperproperties"
    - "a temporal logic for hyperproperties"

Connected through hyperedge HE-3 (induced by source paper "solving qbf by abstraction"):
  with members:
    - "bosy an experimentation framework for bounded synthesis"
    - "on expansion and resolution in cegar based qbf solving"
    - "encodings of bounded synthesis"
    - "the 4th reactive synthesis competition syntcomp 2017 benchmarks participants results"
    - "symbolic vs bounded synthesis for petri games"
    - "the first reactive synthesis competition syntcomp 2014"
    - "the 3rd reactive synthesis competition syntcomp 2016 benchmarks participants results"
    - "petri games synthesis of distributed systems with causal memory"

Connected through hyperedge HE-4 (induced by source paper "expansion based qbf solving without recursion"):
  with members:
    - "evaluating qbf solvers quantifier alternations matter"
    - "on expansion and resolution in cegar based qbf solving"
    - "encodings of bounded synthesis"
    - "depqbf 6 0 a search based qbf solver beyond traditional qcdcl"
    - "structural synthesis for gxw specifications"
    - "conformant planning as a case study of incremental qbf solving"

Connected through hyperedge HE-5 (induced by source paper "on expansion and resolution in cegar based qbf solving"):
  with members:
    - "encodings of bounded synthesis"
    - "on stronger calculi for qbfs"
    - "q resolution with generalized axioms"

Connected through hyperedge HE-6 (induced by source paper "distributed synthesis for parameterized temporal logics"):
  with members:
    - "encodings of bounded synthesis"
    - "distributed prompt ltl synthesis"
    - "parameterized linear temporal logics meet costs still not costlier than ltl"
    - "assume guarantee synthesis for concurrent reactive programs with partial information"
    - "parametric linear dynamic logic"
    - "optimal bounds in parametric ltl games"

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)