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: "backlog and delay reasoning in harq systems"
  Abstract: Recently, hybrid-automatic-repeat-request (HARQ) systems have been favored in particular state-of-the-art communications systems since they provide the practicality of error detections and corrections aligned with repeat-requests when needed at receivers. The queueing characteristics of these systems have taken considerable focus since the current technology demands data transmissions with a minimum delay provisioning. In this paper, we investigate the effects of physical layer characteristics on data link layer performance in a general class of HARQ systems. Constructing a state transition model that combines queue activity at a transmitter and decoding efficiency at a receiver, we identify the probability of clearing the queue at the transmitter and the packet-loss probability at the receiver. We determine the effective capacity that yields the maximum feasible data arrival rate at the queue under quality-of-service constraints. In addition, we put forward non-asymptotic backlog and delay bounds. Finally, regarding three different HARQ protocols, namely Type-I HARQ, HARQ-chase combining (HARQ-CC) and HARQ-incremental redundancy (HARQ-IR), we show the superiority of HARQ-IR in delay robustness over the others. However, we further observe that the performance gap between HARQ-CC and HARQ-IR is quite negligible in certain cases. The novelty of our paper is a general cross-layer analysis of these systems, considering encoding/decoding in the physical layer and delay aspects in the data-link layer.

Connected through hyperedge HE-1 (induced by source paper "effective capacity in wireless networks a comprehensive survey"):
  with members:
    - "ultra reliable and low latency wireless communication tail risk and scale"
    - "performance analysis of noma for ultra reliable and low latency communications"
    - "wireless access for ultra reliable low latency communication urllc principles and building blocks"
    - "secure transmission of delay sensitive data over wireless fading channels"
    - "energy efficient ofdma networks maintaining statistical qos guarantees for delay sensitive traffic"
    - "statistical qos analysis of full duplex and half duplex heterogeneous cellular networks"
    - "effective capacity of retransmission schemes a recurrence relation approach"
    - "delay constrained video transmission quality driven resource allocation and scheduling"

Connected through hyperedge HE-2 (induced by source paper "effective capacity in mimo channels with arbitrary inputs"):
  with members:
    - "the world s first real time testbed for massive mimo design implementation and validation"
    - "linear precoding for the mimo multiple access channel with finite alphabet inputs and statistical csi"
    - "massive mimo systems with non ideal hardware energy efficiency estimation and capacity limits"
    - "massive mimo for next generation wireless systems"
    - "what will 5g be"
    - "linear mimo precoding in jointly correlated fading multiple access channels with finite alphabet signaling"
    - "on the impact of hardware impairments on massive mimo"
    - "on the throughput and energy efficiency of cognitive mimo transmissions"

Connected through hyperedge HE-3 (induced by source paper "outage effective capacity of buffer aided diamond relay systems using harq with incremental redundancy"):
  with members:
    - "effective capacity of retransmission schemes a recurrence relation approach"
    - "achievable rates for the fading half duplex single relay selection network using buffer aided relaying"
    - "statistical delay tradeoffs in buffer aided two hop wireless communication systems"
    - "using superposition codebooks and partial decode and forward in low snr parallel relay networks"
    - "buffer aided relaying with adaptive link selection fixed and mixed rate transmission"
    - "broadcast approaches to the diamond channel"

Connected through hyperedge HE-4 (induced by source paper "effective capacity of retransmission schemes a recurrence relation approach"):
  with members:
    - "finite block length analysis of the incremental redundancy harq"
    - "coding versus arq in fading channels how reliable should the phy be"

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.IT(Information Theory)