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: "a concurrent pattern calculus"
  Abstract: Concurrent pattern calculus drives interaction between processes by unifying patterns, just as sequential pattern calculus drives computation by matching a pattern against a data structure. By generalising from pattern matching to unification, interaction becomes symmetrical, with information flowing in both directions. This provides a natural language for describing any form of exchange or trade. Many popular process calculi can be encoded in concurrent pattern calculus.

Connected through hyperedge HE-1 (induced by source paper "a formal approach to the engineering of domain specific distributed systems"):
  with members:
    - "on the power of attribute based communication"
    - "a rigorous framework for specification analysis and enforcement of access control policies"
    - "tracing where iot data are collected and aggregated"
    - "blind date conversation joining"
    - "psi calculi a framework for mobile processes with nominal data and logic"

Connected through hyperedge HE-2 (induced by source paper "a behavioural theory for interactions in collective adaptive systems"):
  with members:
    - "programming the interactions of collective adaptive systems by relying on attribute based communication"
    - "large scale complex it systems"

Connected through hyperedge HE-3 (induced by source paper "how hard is it to verify flat affine counter systems with the finite monoid property"):
  with members:
    - "reachability in two dimensional vector addition systems with states is pspace complete"
    - "subclasses of presburger arithmetic and the weak exp hierarchy"
    - "deciding conditional termination"
    - "on the complexity of verifying regular properties on flat counter systems"
    - "invariant generation through strategy iteration in succinctly represented control flow graphs"
    - "taming past ltl and flat counter systems"

Connected through hyperedge HE-4 (induced by source paper "a sorted semantic framework for applied process calculi"):
  with members:
    - "on the expressiveness of intensional communication"
    - "psi calculi a framework for mobile processes with nominal data and logic"

Connected through hyperedge HE-5 (induced by source paper "on the power of attribute based communication"):
  with members:
    - "large scale complex it systems"

Connected through hyperedge HE-6 (induced by source paper "on the expressiveness of joining"):
  with members:
    - "an intensional concurrent faithful encoding of turing machines"
    - "on the expressiveness of intensional communication"
    - "musings on encodings and expressiveness"
    - "psi calculi a framework for mobile processes with nominal data and logic"
    - "comparing the expressive power of the synchronous and asynchronous pi calculi"

Connected through hyperedge HE-7 (induced by source paper "reversing single sessions"):
  with members:
    - "globally governed session semantics"
    - "compliance for reversible client server interactions"

Connected through hyperedge HE-8 (induced by source paper "on the expressiveness of intensional communication"):
  with members:
    - "an intensional concurrent faithful encoding of turing machines"
    - "expressiveness via intensionality and concurrency"
    - "musings on encodings and expressiveness"
    - "psi calculi a framework for mobile processes with nominal data and logic"
    - "multiparty symmetric sum types"
    - "formalising the pi calculus using nominal logic"
    - "comparing the expressive power of the synchronous and asynchronous pi calculi"

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)