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 systematic approach for interference alignment in csit less relay aided x networks"
  Abstract: The degrees of freedom (DoF) of an X-network with M transmit and N receive nodes utilizing interference alignment with the support of $J$ relays each equipped with $L_j$ antennas operating in a half-duplex non-regenerative mode is investigated. Conditions on the feasibility of interference alignment are derived using a proper transmit strategy and a structured approach based on a Kronecker-product representation. The advantages of this approach are twofold: First, it extends existing results on the achievable DoF to generalized antenna configurations. Second, it unifies the analysis for time-varying and constant channels and provides valuable insights and interconnections between the two channel models. It turns out that a DoF of $\nicefrac{NM}{M+N-1}$ is feasible whenever the sum of the $L_j^2 \geq [N-1][M-1]$.

Connected through hyperedge HE-1 (induced by source paper "cache assisted broadcast relay wireless networks a delivery time cache memory tradeoff"):
  with members:
    - "fog aided wireless networks for content delivery fundamental latency tradeoffs"
    - "fundamental limits on latency in transceiver cache aided hetnets"
    - "fundamental tradeoff between storage and latency in cache aided wireless interference networks"
    - "waveform and spectrum management for unmanned aerial systems beyond 2025"
    - "cache aided interference management in partially connected wireless networks"
    - "decentralized caching and coded delivery with distinct cache capacities"
    - "content centric sparse multicast beamforming for cache enabled cloud ran"
    - "fundamental limits of cache aided wireless bc interplay of coded caching and csit feedback"

Connected through hyperedge HE-2 (induced by source paper "delivery time minimization in edge caching synergistic benefits of subspace alignment and zero forcing"):
  with members:
    - "fundamental limits on latency in transceiver cache aided hetnets"
    - "fundamental limits on delivery time in cloud and cache aided heterogeneous networks"
    - "waveform and spectrum management for unmanned aerial systems beyond 2025"
    - "fundamental limits of cache aided interference management"
    - "cache aided wireless networks tradeoffs between storage and latency"
    - "cache aided interference channels"
    - "real interference alignment exploiting the potential of single antenna systems"
    - "fundamental limits of caching"

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)