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: "repex a flexible framework for scalable replica exchange molecular dynamics simulations"
  Abstract: Replica Exchange (RE) simulations have emerged as an important algorithmic tool for the molecular sciences. RE simulations involve the concurrent execution of independent simulations which infrequently interact and exchange information. The next set of simulation parameters are based upon the outcome of the exchanges. #R##N#Typically RE functionality is integrated into the molecular simulation software package. A primary motivation of the tight integration of RE functionality with simulation codes has been performance. This is limiting at multiple levels. First, advances in the RE methodology are tied to the molecular simulation code. Consequently these advances remain confined to the molecular simulation code for which they were developed. Second, it is difficult to extend or experiment with novel RE algorithms, since expertise in the molecular simulation code is typically required. #R##N#In this paper, we propose the RepEx framework which address these aforementioned shortcomings of existing approaches, while striking the balance between flexibility (any RE scheme) and scalability (tens of thousands of replicas) over a diverse range of platforms. RepEx is designed to use a pilot-job based runtime system and support diverse RE Patterns and Execution Modes. RE Patterns are concerned with synchronization mechanisms in RE simulation, and Execution Modes with spatial and temporal mapping of workload to the CPU cores. We discuss how the design and implementation yield the following primary contributions of the RepEx framework: (i) its ability to support different RE schemes independent of molecular simulation codes, (ii) provide the ability to execute different exchange schemes and replica counts independent of the specific availability of resources, (iii) provide a runtime system that has first-class support for task-level parallelism, and (iv) required scalability along multiple dimensions.

Connected through hyperedge HE-1 (induced by source paper "radical cybertools middleware building blocks for scalable science"):
  with members:
    - "rapid concurrent and adaptive extreme scale binding free energy calculation"
    - "extasy scalable and flexible coupling of md simulations and advanced sampling techniques"
    - "using pilot systems to execute many task workloads on supercomputers"
    - "integrating abstractions to enhance the execution of distributed applications"

Connected through hyperedge HE-2 (induced by source paper "task parallel analysis of molecular dynamics trajectories"):
  with members:
    - "high throughput binding affinity calculations at extreme scales"
    - "hadoop on hpc integrating hadoop and pilot based dynamic resource management"
    - "extasy scalable and flexible coupling of md simulations and advanced sampling techniques"
    - "using pilot systems to execute many task workloads on supercomputers"
    - "a comprehensive perspective on pilot job systems"
    - "mllib machine learning in apache spark"
    - "a tale of two data intensive paradigms applications abstractions and architectures"
    - "p a model of pilot abstractions"

Connected through hyperedge HE-3 (induced by source paper "design and performance characterization of radical pilot on titan"):
  with members:
    - "extasy scalable and flexible coupling of md simulations and advanced sampling techniques"
    - "synapse bridging the gap towards predictable workload placement"

Connected through hyperedge HE-4 (induced by source paper "high throughput binding affinity calculations at extreme scales"):
  with members:
    - "rapid concurrent and adaptive extreme scale binding free energy calculation"
    - "converging high throughput and high performance computing a case study"
    - "ensemble toolkit scalable and flexible execution of ensembles of tasks"
    - "extasy scalable and flexible coupling of md simulations and advanced sampling techniques"
    - "analysis of distributed execution of workloads"

Connected through hyperedge HE-5 (induced by source paper "designing workflow systems using building blocks"):
  with members:
    - "synapse synthetic application profiler and emulator"
    - "converging high throughput and high performance computing a case study"
    - "microservices yesterday today and tomorrow"
    - "ensemble toolkit scalable and flexible execution of ensembles of tasks"
    - "extasy scalable and flexible coupling of md simulations and advanced sampling techniques"
    - "analysis of distributed execution of workloads"
    - "executing dynamic and heterogeneous workloads on super computers"
    - "integrating abstractions to enhance the execution of distributed applications"

Connected through hyperedge HE-6 (induced by source paper "ensemble toolkit scalable and flexible execution of ensembles of tasks"):
  with members:
    - "extasy scalable and flexible coupling of md simulations and advanced sampling techniques"
    - "radical pilot scalable execution of heterogeneous and dynamic workloads on supercomputers"
    - "integrating abstractions to enhance the execution of distributed applications"

Connected through hyperedge HE-7 (induced by source paper "hadoop on hpc integrating hadoop and pilot based dynamic resource management"):
  with members:
    - "radical pilot scalable execution of heterogeneous and dynamic workloads on supercomputers"
    - "a tale of two data intensive paradigms applications abstractions and architectures"

Connected through hyperedge HE-8 (induced by source paper "using pilot systems to execute many task workloads on supercomputers"):
  with members:
    - "ensemble toolkit scalable and flexible execution of ensembles of tasks"
    - "extasy scalable and flexible coupling of md simulations and advanced sampling techniques"
    - "executing dynamic and heterogeneous workloads on super computers"
    - "p a model of pilot abstractions"

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.DC(Distributed, Parallel, and Cluster Computing)