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: "simultaneous wireless information and power transfer in modern communication systems"
  Abstract: Energy harvesting for wireless communication networks is a new paradigm that allows terminals to recharge their batteries from external energy sources in the surrounding environment. A promising energy harvesting technology is wireless power transfer where terminals harvest energy from electromagnetic radiation. Thereby, the energy may be harvested opportunistically from ambient electromagnetic sources or from sources that intentionally transmit electromagnetic energy for energy harvesting purposes. A particularly interesting and challenging scenario arises when sources perform simultaneous wireless information and power transfer (SWIPT), as strong signals not only increase power transfer but also interference. This article provides an overview of SWIPT systems with a particular focus on the hardware realization of rectenna circuits and practical techniques that achieve SWIPT in the domains of time, power, antennas, and space. The article also discusses the benefits of a potential integration of SWIPT technologies in modern communication networks in the context of resource allocation and cooperative cognitive radio networks.

Connected through hyperedge HE-1 (induced by source paper "wirelessly powered sensor networks power allocation for channel estimation and energy beamforming"):
  with members:
    - "cluster based wireless energy transfer for low complex energy receivers"
    - "wireless energy beamforming using received signal strength indicator feedback"
    - "on the beneficial roles of fading and transmit diversity in wireless power transfer with nonlinear energy harvesting"
    - "waveform design for wireless power transfer with limited feedback"
    - "distributed wireless power transfer with energy feedback"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "on the feasibility of wireless energy transfer using massive antenna arrays"
    - "waveform design for wireless power transfer"

Connected through hyperedge HE-2 (induced by source paper "energy efficiency optimization for secure transmission in miso cognitive radio network with energy harvesting"):
  with members:
    - "robust designs of beamforming and power splitting for distributed antenna systems with wireless energy harvesting"
    - "enhancing phy security of miso noma swipt systems with a practical non linear eh model"
    - "resource allocation for secure miso noma cognitive radios relying on swipt"
    - "secure communications with cooperative jamming optimal power allocation and secrecy outage analysis"
    - "physical layer security jamming theoretical limits and practical designs in wireless networks"
    - "beamforming and power splitting designs for an aided secure multi user mimo swipt systems"
    - "secure energy efficiency optimization for miso cognitive radio network with energy harvesting"
    - "limited feedback scheme for device to device communications in 5g cellular networks with reliability and cellular secrecy outage constraints"

Connected through hyperedge HE-3 (induced by source paper "specific absorption rate aware beamforming in miso downlink swipt systems"):
  with members:
    - "signal and system design for wireless power transfer prototype experiment and validation"
    - "fundamentals of wireless information and power transfer from rf energy harvester models to signal and system designs"
    - "a learning approach to wireless information and power transfer signal and system design"
    - "wireless information and power transfer over an awgn channel nonlinearity and asymmetric gaussian signaling"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "waveform design for wireless power transfer"
    - "wireless information and power transfer nonlinearity waveform design and rate energy tradeoff"
    - "safe and secure wireless power transfer networks challenges and opportunities in rf based systems"

Connected through hyperedge HE-4 (induced by source paper "ultra small cell networks with collaborative rf and lightwave power transfer"):
  with members:
    - "robust design of ac computing enabled receiver architecture for swipt networks"
    - "fundamentals of wireless information and power transfer from rf energy harvester models to signal and system designs"
    - "green cell less design for rf wireless power transfer networks"
    - "rf wireless power transfer regreening future networks"
    - "coverage and rate analysis for co existing rf vlc downlink cellular networks"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "waveform design for wireless power transfer"
    - "practical non linear energy harvesting model and resource allocation for swipt systems"

Connected through hyperedge HE-5 (induced by source paper "multi tone signal optimization for wireless power transfer in the presence of wireless communication links"):
  with members:
    - "retrodirective multi user wireless power transfer with massive mimo"
    - "low complexity adaptive multisine waveform design for wireless power transfer"
    - "waveform optimization for radio frequency wireless power transfer"
    - "waveform design for wireless power transfer"
    - "waveform optimization for swipt with nonlinear energy harvester modeling"
    - "wireless powered communication opportunities and challenges"
    - "practical non linear energy harvesting model and resource allocation for swipt systems"
    - "multi antenna wireless energy transfer for backscatter communication systems"

Connected through hyperedge HE-6 (induced by source paper "robust design of ac computing enabled receiver architecture for swipt networks"):
  with members:
    - "fundamentals of wireless information and power transfer from rf energy harvester models to signal and system designs"
    - "rf wireless power transfer regreening future networks"
    - "robust chance constrained optimization for power efficient and secure swipt systems"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "waveform design for wireless power transfer"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "wireless information and power transfer architecture design and rate energy tradeoff"
    - "mimo broadcasting for simultaneous wireless information and power transfer"

Connected through hyperedge HE-7 (induced by source paper "system outage performance for three step two way energy harvesting df relaying"):
  with members:
    - "heterogeneous power splitting based two way df relaying with non linear energy harvesting"
    - "optimization of a power splitting protocol for two way multiple energy harvesting relay system"
    - "simultaneous information and energy flow for iot relay systems with crowd harvesting"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "relaying protocols for wireless energy harvesting and information processing"
    - "a simple cooperative diversity method based on network path selection"

Connected through hyperedge HE-8 (induced by source paper "optimal online transmission policy in wireless powered networks with urgency aware age of information"):
  with members:
    - "optimal status update for age of information minimization with an energy harvesting source"
    - "group cooperation with optimal resource allocation in wireless powered communication networks"
    - "uplink age of information of unilaterally powered two way data exchanging systems"
    - "waveform design for wireless power transfer"
    - "update or wait how to keep your data fresh"
    - "mimo broadcasting for simultaneous wireless information and power transfer"

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)