human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "fundamental green tradeoffs progresses challenges and impacts on 5g networks"):
  Abstract: With years of tremendous traffic and energy consumption growth, green radio has been valued not only for theoretical research interests but also for the operational expenditure reduction and the sustainable development of wireless communications. Fundamental green tradeoffs, served as an important framework for analysis, include four basic relationships: 1) spectrum efficiency versus energy efficiency; 2) deployment efficiency versus energy efficiency; 3) delay versus power; and 4) bandwidth versus power. In this paper, we first provide a comprehensive overview on the extensive on-going research efforts and categorize them based on the fundamental green tradeoffs. We will then focus on research progresses of 4G and 5G communications, such as orthogonal frequency division multiplexing and non-orthogonal aggregation, multiple input multiple output, and heterogeneous networks. We will also discuss potential challenges and impacts of fundamental green tradeoffs, to shed some light on the energy efficient research and design for future wireless networks.

Includes members:
  Member "spectrum power trading for energy efficient small cell":
    also connected through other hyperedges:
      (none)
  Member "power efficient resource allocation for full duplex radio distributed antenna networks":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "joint trajectory and resource allocation design for energy efficient secure uav communication systems")
  Member "energy recycling full duplex radios for next generation networks":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "massive wireless energy transfer enabling sustainable iot towards 6g era")
  Member "energy efficient resource allocation for wireless powered communication networks":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "common throughput maximization for uav enabled interference channel with wireless powered communications")
  Member "multi objective optimization for robust power efficient and secure full duplex wireless communication systems":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "joint trajectory and resource allocation design for energy efficient secure uav communication systems")
  Member "hybrid millimeter wave systems a novel paradigm for hetnets":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "dual band fading multiple access relay channels")
  Member "coexistence of wi fi and heterogeneous small cell networks sharing unlicensed spectrum":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "power allocation in multi user cellular networks deep reinforcement learning approaches")
  Member "on the spectral efficiency of full duplex small cell wireless systems":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "optimal centralized dynamic time division duplex")

Question: Please tell me which class the source paper 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)