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: "optimal design of non orthogonal multiple access with wireless power transfer"
  Abstract: In this work, we study a non-orthogonal multiple access scheme used for the uplink of a wireless-powered communication system. We focus on data rates optimization and fairness increase. We show that the formulated optimization problems can be optimally and efficiently solved by either linear programming methods or convex optimization, which means that the proposed scheme can be easily implemented in practical applications. Simulation results illustrate that the proposed scheme outperforms the baseline orthogonal scheme, while they reveal the dependence between sum-throughput, minimum data rate, and wireless power transfer.

Connected through hyperedge HE-1 (induced by source paper "online policies for throughput maximization of energy constrained wireless powered communication systems"):
  with members:
    - "optimization of energy constrained wireless powered communication networks with heterogeneous nodes"
    - "wireless power meets energy harvesting a joint energy allocation approach in ofdm based system"
    - "resource allocation and fairness in wireless powered cooperative cognitive radio networks"
    - "battery powered devices in wpcns"
    - "on optimal policies in full duplex wireless powered communication networks"
    - "an overview of sustainable green 5g networks"
    - "dynamic base station operation in large scale green cellular networks"
    - "energy efficient resource allocation for wireless powered communication networks"

Connected through hyperedge HE-2 (induced by source paper "a survey on non orthogonal multiple access for 5g networks research challenges and future trends"):
  with members:
    - "exploiting multiple antenna techniques for non orthogonal multiple access"
    - "achievable rate region of non orthogonal multiple access systems with wireless powered decoder"
    - "a new view of multi user hybrid massive mimo non orthogonal angle division multiple access"
    - "on non orthogonal multiple access with finite alphabet inputs in z channels"
    - "spectrum and energy efficient beamspace mimo noma for millimeter wave communications using lens antenna array"
    - "practical power balanced non orthogonal multiple access"
    - "noma based random access with multichannel aloha"
    - "optimal power allocation scheme for non orthogonal multiple access with alpha fairness"

Connected through hyperedge HE-3 (induced by source paper "non orthogonal multiple access schemes in wireless powered communication networks"):
  with members:
    - "optimization of energy constrained wireless powered communication networks with heterogeneous nodes"
    - "wireless powered communications with non orthogonal multiple access"
    - "battery powered devices in wpcns"
    - "on optimal policies in full duplex wireless powered communication networks"
    - "energy harvesting networks with energy cooperation procrastinating policies"
    - "joint transmission and energy transfer policies for energy harvesting devices with finite batteries"
    - "user cooperation in wireless powered communication networks"
    - "throughput maximization in wireless powered communication networks"

Connected through hyperedge HE-4 (induced by source paper "a survey of downlink non orthogonal multiple access for 5g wireless communication networks"):
  with members:
    - "power efficient resource allocation for mc noma with statistical channel state information"
    - "analysis and design of secure massive mimo systems in the presence of hardware impairments"
    - "nonorthogonal multiple access in large scale underlay cognitive radio networks"
    - "design of massive mimo noma with limited feedback"
    - "optimal joint power and subcarrier allocation for mc noma systems"
    - "secrecy sum rate maximization in non orthogonal multiple access"
    - "relay selection for cooperative noma"
    - "non orthogonal multiple access for visible light communications"

Connected through hyperedge HE-5 (induced by source paper "robust energy harvesting based on a stackelberg game"):
  with members:
    - "throughput maximization in wireless powered communication networks"
    - "multi antenna wireless powered communication with energy beamforming"

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)