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: "base station sleeping and resource allocation in renewable energy powered cellular networks"
  Abstract: We consider energy-efficient wireless resource management in cellular networks where base stations (BSs) are equipped with energy harvesting devices, using statistical information for traffic intensity and renewable energy. The problem is formulated as adapting BSs' on-off states, active resource blocks (e.g., subcarriers), and renewable energy allocation to minimize the average grid power consumption while satisfying the users' quality of service (blocking probability) requirements. It is transformed into an unconstrained optimization problem to minimize a weighted sum of grid power consumption and blocking probability. A two-stage dynamic programming algorithm is proposed to solve this problem, by which the BSs' on-off states are optimized in the first stage, and the active BSs' resource blocks are allocated iteratively in the second stage. Compared with the optimal joint BSs' on-off states and active resource blocks allocation algorithm, the proposed algorithm greatly reduces the computational complexity and can achieve the optimal performance when the traffic is uniformly distributed.

Connected through hyperedge HE-1 (induced by source paper "joint user association and bs switching scheme for green heterogeneous cellular network"):
  with members:
    - "heterogeneous cellular networks with flexible cell association a comprehensive downlink sinr analysis"
    - "user association for load balancing in heterogeneous cellular networks"

Connected through hyperedge HE-2 (induced by source paper "base station on off switching in 5g wireless networks approaches and challenges"):
  with members:
    - "boost base station on off switching strategy for energy efficient massive mimo hetnets"
    - "energy aware traffic offloading for green heterogeneous networks"
    - "green 5g heterogeneous networks through dynamic small cell operation"
    - "how many small cells can be turned off via vertical offloading under a separation architecture"
    - "what will 5g be"
    - "adaptive power management for wireless base stations in a smart grid environment"

Connected through hyperedge HE-3 (induced by source paper "grid energy consumption and qos tradeoff in hybrid energy supply wireless networks"):
  with members:
    - "transmit power minimization for wireless networks with energy harvesting relays"
    - "energy harvesting wireless communications a review of recent advances"
    - "comp meets smart grid a new communication and energy cooperation paradigm"
    - "energy harvesting small cell networks feasibility deployment and operation"
    - "a lyapunov optimization approach for green cellular networks with hybrid energy supplies"
    - "cost minimization for fading channels with energy harvesting and conventional energy"
    - "power allocation for conventional and buffer aided link adaptive relaying systems with energy harvesting nodes"
    - "multiuser joint energy bandwidth allocation with energy harvesting part i optimum algorithm multiple point to point channels"

Connected through hyperedge HE-4 (induced by source paper "policy optimization for content push via energy harvesting small cells in heterogeneous networks"):
  with members:
    - "stochastic content centric multicast scheduling for cache enabled heterogeneous cellular networks"
    - "wireless caching technical misconceptions and business barriers"
    - "on the tradeoff between energy harvesting and caching in wireless networks"
    - "greendelivery proactive content caching and push with energy harvesting based small cells"
    - "proactive push with energy harvesting based small cells in heterogeneous networks"
    - "energy harvesting small cell networks feasibility deployment and operation"
    - "learning based optimization of cache content in a small cell base station"
    - "multicast aware caching for small cell networks"

Connected through hyperedge HE-5 (induced by source paper "dynamic computation offloading for mobile edge computing with energy harvesting devices"):
  with members:
    - "delay optimal computation task scheduling for mobile edge computing systems"
    - "grid energy consumption and qos tradeoff in hybrid energy supply wireless networks"
    - "distributed real time power balancing in renewable integrated power grids with storage and flexible loads"
    - "arq with adaptive feedback for energy harvesting receivers"
    - "power delay tradeoff in multi user mobile edge computing systems"
    - "decentralized computation offloading game for mobile cloud computing"
    - "energy harvesting wireless communications a review of recent advances"
    - "energy harvesting small cell networks feasibility deployment and operation"

Connected through hyperedge HE-6 (induced by source paper "online ski rental for on off scheduling of energy harvesting base stations"):
  with members:
    - "distributed user association in energy harvesting small cell networks a probabilistic bandit model"
    - "dynamic clustering and on off strategies for wireless small cell networks"
    - "gate greening at the edges"
    - "millimeter wave cellular networks a mac layer perspective"
    - "energy harvesting small cell networks feasibility deployment and operation"
    - "5g wireless backhaul networks challenges and research advances"
    - "dynamic clustering and sleep mode strategies for small cell networks"
    - "millimeter wave cellular wireless networks potentials and challenges"

Connected through hyperedge HE-7 (induced by source paper "online ski rental for on off scheduling of energy harvesting millimeter wave base stations"):
  with members:
    - "gate greening at the edges"
    - "millimeter wave cellular networks a mac layer perspective"
    - "energy harvesting small cell networks feasibility deployment and operation"
    - "5g wireless backhaul networks challenges and research advances"
    - "millimeter wave cellular wireless networks potentials and challenges"
    - "millimeter wave channel modeling and cellular capacity evaluation"
    - "millimeter wave beamforming for wireless backhaul and access in small cell networks"
    - "analysis of blockage effects on urban cellular networks"

Connected through hyperedge HE-8 (induced by source paper "energy aware traffic offloading for green heterogeneous networks"):
  with members:
    - "how many small cells can be turned off via vertical offloading under a separation architecture"
    - "what will 5g be"
    - "energy efficient resource allocation in ofdma systems with hybrid energy harvesting base station"
    - "fundamentals of heterogeneous cellular networks with energy harvesting"
    - "user association for load balancing in heterogeneous cellular networks"
    - "optimal packet scheduling on an energy harvesting broadcast link"
    - "optimal packet scheduling in an energy harvesting communication system"

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)