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: "relay selection for wireless communications against eavesdropping a security reliability trade off perspective"
  Abstract: This article examines secrecy coding aided wireless communications from a source to a destination in the presence of an eavesdropper from an SRT perspective. Explicitly, security is quantified in terms of the intercept probability experienced at the eavesdropper, while the outage probability encountered at the destination is used to measure transmission reliability. We characterize the SRT of conventional direct transmission from the source to the destination and show that if the outage probability is increased, the intercept probability decreases, and vice versa. We first demonstrate that the employment of relay nodes for assisting source-destination transmission is capable of defending against eavesdropping, followed by quantifying the benefits of SRS as well as MRS schemes. More specifically, in the SRS scheme, only the single "best" relay is selected for forwarding the source signal to the destination, whereas the MRS scheme allows multiple relays to participate in this process. It is illustrated that both the SRS and MRS schemes achieve a better SRT than conventional direct transmission, especially upon increasing the number of relays. Numerical results also show that, as expected, MRS outperforms SRS in terms of its SRT. Additionally, we present some open challenges and future directions for wireless relay aided physical-layer security.

Connected through hyperedge HE-1 (induced by source paper "security reliability tradeoff for distributed antenna systems in heterogeneous cellular networks"):
  with members:
    - "game based approach for qos provisioning and interference management in heterogeneous networks"
    - "intelligent interference exploitation for heterogeneous cellular networks against eavesdropping"
    - "energy efficiency analysis of heterogeneous cellular networks with extra cell range expansion"
    - "secrecy optimized resource allocation for device to device communication underlaying heterogeneous networks"
    - "safeguarding decentralized wireless networks using full duplex jamming receivers"
    - "optimal beamforming for gaussian mimo wiretap channels with two transmit antennas"
    - "a survey on wireless security technical challenges recent advances and future trends"
    - "physical layer security in heterogeneous cellular networks"

Connected through hyperedge HE-2 (induced by source paper "intelligent interference exploitation for heterogeneous cellular networks against eavesdropping"):
  with members:
    - "robust and secure resource allocation for full duplex miso multicarrier noma systems"
    - "physical layer security in wireless ad hoc networks under a hybrid full half duplex receiver deployment strategy"
    - "safeguarding decentralized wireless networks using full duplex jamming receivers"
    - "power constrained secrecy rate maximization for joint relay and jammer selection assisted wireless networks"
    - "physical layer security for spectrum sharing systems"
    - "on secrecy performance of antenna selection aided mimo systems against eavesdropping"
    - "analytical modeling of interference aware power control for the uplink of heterogeneous cellular networks"
    - "a survey on wireless security technical challenges recent advances and future trends"

Connected through hyperedge HE-3 (induced by source paper "a survey on wireless security technical challenges recent advances and future trends"):
  with members:
    - "improving physical layer security in wireless communications using diversity techniques"
    - "securing physical layer communications for cognitive radio networks"
    - "secrecy outage and diversity analysis of cognitive radio systems"
    - "security versus reliability analysis of opportunistic relaying"
    - "what will 5g be"
    - "intercept probability analysis of cooperative wireless networks with best relay selection in the presence of eavesdropping attack"
    - "optimal relay selection for physical layer security in cooperative wireless networks"
    - "physical layer security with multiuser scheduling in cognitive radio networks"

Connected through hyperedge HE-4 (induced by source paper "secure communication via a wireless energy harvesting untrusted relay"):
  with members:
    - "rf based energy harvesting in decode and forward relaying systems ergodic and outage capacities"
    - "secrecy wireless information and power transfer in fading wiretap channel"
    - "wireless powered relays in cooperative communications time switching relaying protocols and throughput analysis"
    - "distributed power splitting for swipt in relay interference channels using game theory"
    - "interference assisted wireless energy harvesting in cognitive relay network with multiple primary transceivers"
    - "robust beamforming for secure communication in systems with wireless information and power transfer"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "secure beamforming for mimo broadcasting with 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)