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: "explicit fairness in testing semantics"
  Abstract: In this paper we investigate fair computations in the $\pi$-calculus \cite{MPW92}. Following Costa and Stirling's approach for CCS-like languages \cite{CS84,CS87}, we consider a method to label process actions in order to filter out unfair computations. We contrast the existing fair-testing notion \cite{RV07,NC95} with those that naturally arise by imposing weak and strong fairness. This comparison provides insight about the expressiveness of the various `fair' testing semantics and about their discriminating power.

Connected through hyperedge HE-1 (induced by source paper "progress justness and fairness"):
  with members:
    - "analysing mutual exclusion using process algebra with signals"
    - "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"
    - "a process algebra for wireless mesh networks"
    - "a process algebra for wireless mesh networks used for modelling verifying and analysing aodv"

Connected through hyperedge HE-2 (induced by source paper "type checking liveness for collaborative processes with bounded and unbounded recursion"):
  with members:
    - "multiparty compatibility in communicating automata characterisation and synthesis of global session types"
    - "from lock freedom to progress using session types"
    - "a graphical approach to progress for structured communication in web services"

Connected through hyperedge HE-3 (induced by source paper "full abstraction for fair testing in ccs"):
  with members:
    - "cartesian closed 2 categories and permutation equivalence in higher order rewriting"
    - "initiality for typed syntax and semantics"
    - "innocent strategies as presheaves and interactive equivalences for ccs"

Connected through hyperedge HE-4 (induced by source paper "fully abstract concurrent games for pi"):
  with members:
    - "full abstraction for fair testing in ccs"
    - "innocent strategies as presheaves and interactive equivalences for ccs"

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)