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: "delay optimal power and precoder adaptation for multi stream mimo systems"
  Abstract: In this paper, we consider delay-optimal MIMO precoder and power allocation design for a MIMO Link in wireless fading channels. There are $L$ data streams spatially multiplexed onto the MIMO link with heterogeneous packet arrivals and delay requirements. The transmitter is assumed to have knowledge of the channel state information (CSI) as well as the joint queue state information (QSI) of the $L$ buffers. Using $L$-dimensional Markov Decision Process (MDP), we obtain optimal precoding and power allocation policies for general delay regime, which consists of an online solution and an offline solution. The online solution has negligible complexity but the offline solution has worst case complexity ${\cal O}((N+1)^L)$ where $N$ is the buffer size. Using {\em static sorting} of the $L$ eigenchannels, we decompose the MDP into $L$ independent 1-dimensional subproblems and obtained low complexity offline solution with linear complexity order ${\cal O}(NL)$ and close-to-optimal performance.

Connected through hyperedge HE-1 (induced by source paper "transmit power minimization in small cell networks under time average qos constraints"):
  with members:
    - "open vs closed access femtocells in the uplink"
    - "dynamic resource allocation in cognitive radio networks"
    - "femto macro cellular interference control with subband scheduling and interference cancelation"
    - "stability and delay of zero forcing sdma with limited feedback"
    - "training and feedback optimization for multiuser mimo downlink"
    - "on peak versus average interference power constraints for protecting primary users in cognitive radio networks"

Connected through hyperedge HE-2 (induced by source paper "dynamic partial cooperative mimo system for delay sensitive applications with limited backhaul capacity"):
  with members:
    - "solving pomdps by searching the space of finite policies"
    - "optimized data sharing in multicell mimo with finite backhaul capacity"
    - "degrees of freedom of the mimo interference channel with cooperation and cognition"

Connected through hyperedge HE-3 (induced by source paper "decentralized delay optimal control for interference networks with limited renewable energy storage"):
  with members:
    - "solving pomdps by searching the space of finite policies"
    - "cooperative algorithms for mimo interference channels"
    - "degrees of freedom of the k user m times n mimo interference channel"
    - "approaching the capacity of wireless networks through distributed interference alignment"
    - "competitive design of multiuser mimo systems based on game theory a unified view"
    - "experiments with infinite horizon policy gradient estimation"

Connected through hyperedge HE-4 (induced by source paper "delay optimal user scheduling and inter cell interference management in cellular network via distributive stochastic learning"):
  with members:
    - "solving pomdps by searching the space of finite policies"

Connected through hyperedge HE-5 (induced by source paper "delay sensitive distributed power and transmission threshold control for s aloha network with finite state markov fading channels"):
  with members:
    - "solving pomdps by searching the space of finite policies"
    - "policy iteration for decentralized control of markov decision processes"
    - "delay optimal power and subcarrier allocation for ofdma systems via stochastic approximation"

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)