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: "on cooperative relaying schemes for wireless physical layer security"
  Abstract: We consider a cooperative wireless network in the presence of one or more eavesdroppers, and exploit node cooperation for achieving physical (PHY) layer based security. Two different cooperation schemes are considered. In the first scheme, cooperating nodes retransmit a weighted version of the source signal in a decode-and-forward (DF) fashion. In the second scheme, referred to as cooperative jamming (CJ), while the source is transmitting, cooperating nodes transmit weighted noise to confound the eavesdropper. We investigate two objectives: i) maximization of the achievable secrecy rate subject to a total power constraint and ii) minimization of the total power transmit power under a secrecy rate constraint. For the first design objective, we obtain the exact solution for the DF scheme for the case of a single or multiple eavasdroppers, while for the CJ scheme with a single eavesdropper we reduce the multivariate problem to a problem of one variable. For the second design objective, existing work introduces additional constraints in order to reduce the degree of difficulty, thus resulting in suboptimal solutions. Our work raises those constraints, and obtains either an analytical solution for the DF scheme with a single eavesdropper, or reduces the multivariate problem to a problem of one variable for the CJ scheme with a single eavesdropper. Numerical results are presented to illustrate the proposed results and compare them to existing work.

Connected through hyperedge HE-1 (induced by source paper "interplay between noma and other emerging technologies a survey"):
  with members:
    - "secure relaying in non orthogonal multiple access trusted and untrusted scenarios"
    - "securing downlink massive mimo noma networks with artificial noise"
    - "lens based millimeter wave reconfigurable antenna noma"
    - "what role can noma play in massive mimo"
    - "noma an information theoretic perspective"
    - "joint power and time allocation for noma mec offloading"
    - "multi beam noma for hybrid mmwave systems"
    - "exploiting full half duplex user relaying in noma systems"

Connected through hyperedge HE-2 (induced by source paper "robust and secure wireless communications via intelligent reflecting surfaces"):
  with members:
    - "over the air computation via intelligent reflecting surfaces"
    - "secure wireless communication via intelligent reflecting surface"
    - "capacity characterization for intelligent reflecting surface aided mimo communication"
    - "resource allocation for secure irs assisted multiuser miso systems"
    - "enabling secure wireless communications via intelligent reflecting surfaces"
    - "intelligent reflecting surface assisted secrecy communication is artificial noise helpful or not"
    - "secrecy rate maximization for intelligent reflecting surface assisted multi antenna communications"
    - "intelligent reflecting surface assisted secrecy communication via joint beamforming and jamming"

Connected through hyperedge HE-3 (induced by source paper "resource allocation for secure gaussian parallel relay channels with finite length coding and discrete constellations"):
  with members:
    - "enhancing physical layer security in af relay assisted multicarrier wireless transmission enhancing physical layer security in af relay assisted multicarrier wireless transmission"
    - "joint relay selection and power allocation in large scale mimo systems with untrusted relays and passive eavesdroppers"
    - "secrecy optimized resource allocation for device to device communication underlaying heterogeneous networks"
    - "optimal power allocation by imperfect hardware analysis in untrusted relaying networks"
    - "secure communication over parallel relay channel"
    - "secure and reliable transmission with cooperative relays in two hop wireless networks"
    - "on secrecy rate analysis of mimo wiretap channels driven by finite alphabet input"
    - "sum rate maximized resource allocation in multiple df relays aided ofdm transmission"

Connected through hyperedge HE-4 (induced by source paper "energy efficient wireless powered secure transmission with cooperative jamming for public transportation"):
  with members:
    - "wireless powered cooperative jamming for secure ofdm system"
    - "cooperative strategies for wireless powered communications"
    - "wireless powered communication opportunities and challenges"
    - "optimal resource allocation in full duplex wireless powered communication network"
    - "optimal and robust transmit designs for miso channel secrecy by semidefinite programming"

Connected through hyperedge HE-5 (induced by source paper "on secure wireless communications for service oriented computing"):
  with members:
    - "principles of physical layer security in multiuser wireless networks a survey"
    - "cooperative jamming for secure communications in mimo relay networks"
    - "on the throughput cost of physical layer security in decentralized wireless networks"
    - "the secrecy graph and some of its properties"
    - "a simple cooperative diversity method based on network path selection"

Connected through hyperedge HE-6 (induced by source paper "wireless powered cooperative jamming for secure ofdm system"):
  with members:
    - "waveform optimization for radio frequency wireless power transfer"
    - "waveform design for wireless power transfer"
    - "secrecy wireless information and power transfer in fading wiretap channel"
    - "a general design framework for mimo wireless energy transfer with limited feedback"
    - "wireless power transfer in massive mimo aided hetnets with user association"
    - "accumulate and jam towards secure communication via a wireless powered full duplex jammer"
    - "communications and signals design for wireless power transmission"
    - "to harvest and jam a paradigm of self sustaining friendly jammers for secure af relaying"

Connected through hyperedge HE-7 (induced by source paper "power constrained secrecy rate maximization for joint relay and jammer selection assisted wireless networks"):
  with members:
    - "a survey on wireless security technical challenges recent advances and future trends"
    - "joint relay and jammer selection improves the physical layer security in the face of csi feedback delays"
    - "improving physical layer security in wireless communications using diversity techniques"
    - "multi antenna relay aided wireless physical layer security"
    - "optimization of code rates in sisome wiretap channels"
    - "optimal relay selection for physical layer security in cooperative wireless networks"
    - "joint relay and jammer selection for secure two way relay networks"
    - "cooperative jamming for secure communications in mimo relay networks"

Connected through hyperedge HE-8 (induced by source paper "secure energy efficiency optimization for miso cognitive radio network with energy harvesting"):
  with members:
    - "secure communications with cooperative jamming optimal power allocation and secrecy outage analysis"
    - "physical layer security jamming theoretical limits and practical designs in wireless networks"
    - "secrecy rate maximization for miso multicasting swipt system with power splitting scheme"
    - "power efficient and secure multiuser communication systems with wireless information and power transfer"
    - "evolution toward 5g multi tier cellular wireless networks an interference management perspective"
    - "wireless information and power transfer architecture design and rate energy tradeoff"

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)