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: "secure communication via a wireless energy harvesting untrusted relay"
  Abstract: The broadcast nature of the wireless medium allows unintended users to eavesdrop the confidential information transmission. In this regard, we investigate the problem of secure communication between a source and a destination via a wireless energy harvesting untrusted node which acts as a helper to relay the information; however, the source and destination nodes wish to keep the information confidential from the relay node. To realize the positive secrecy rate, we use destination-assisted jamming. Being an energy-starved node, the untrusted relay harvests energy from the received radio frequency signals, which include the source's information signal and the destination's jamming signal. Thus, we utilize the jamming signal efficiently by leveraging it as a useful energy source. At the relay, to enable energy harvesting and information processing, we adopt power splitting (PS) and time switching (TS) policies. To evaluate the secrecy performance of this proposed scenario, we derive analytical expressions for two important metrics, viz., the secrecy outage probability and the ergodic secrecy rate. The numerical analysis reveals the design insights into the effects of different system parameters like power splitting ratio, energy harvesting time, target secrecy rate, transmit signal-to-noise ratio (SNR), relay location, and energy conversion efficiency factor, on the secrecy performance. Specifically, the PS policy achieves better optimal secrecy outage probability and optimal ergodic secrecy rate than that of the TS policy at higher target secrecy rate and transmit SNR, respectively.

Connected through hyperedge HE-1 (induced by source paper "secure transmission and self energy recycling with partial eavesdropper csi"):
  with members:
    - "power allocation for secure swipt systems with wireless powered cooperative jamming"
    - "proactive eavesdropping in relaying systems"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "secure communications in the presence of a buffer aided wireless powered relay with self energy recycling"
    - "robust an aided beamforming and power splitting design for secure miso cognitive radio with swipt"
    - "accumulate and jam towards secure communication via a wireless powered full duplex jammer"
    - "secure massive mimo transmission with an active eavesdropper"
    - "full duplex wireless powered relay with self energy recycling"

Connected through hyperedge HE-2 (induced by source paper "optimization of a power splitting protocol for two way multiple energy harvesting relay system"):
  with members:
    - "rf based energy harvesting in decode and forward relaying systems ergodic and outage capacities"
    - "throughput maximization for two way relay channels with energy harvesting nodes the impact of relaying strategies"
    - "wireless powered relays in cooperative communications time switching relaying protocols and throughput analysis"
    - "energy harvesting wireless communications a review of recent advances"
    - "outage analysis of cooperative transmission with energy harvesting relay time switching vs power splitting"
    - "joint resource optimization for multicell networks with wireless energy harvesting relays"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "relaying protocols for wireless energy harvesting and information processing"

Connected through hyperedge HE-3 (induced by source paper "on secure communication using rf energy harvesting two way untrusted relay"):
  with members:
    - "interference aided energy harvesting cognitive relaying with multiple primary transceivers"
    - "joint power splitting and secure beamforming design in the wireless powered untrusted relay networks"
    - "secure communication via an untrusted non regenerative relay in fading channels"
    - "relaying protocols for wireless energy harvesting and information processing"
    - "wireless information and power transfer in two way amplify and forward relaying channels"
    - "wireless information and power transfer architecture design and rate energy tradeoff"
    - "robust beamforming for wireless information and power transmission"
    - "construction of wiretap codes from ordinary channel codes"

Connected through hyperedge HE-4 (induced by source paper "energy harvesting based secure two way communication using an untrusted relay"):
  with members:
    - "joint relay selection and power allocation in large scale mimo systems with untrusted relays and passive eavesdroppers"
    - "optimal power allocation and secrecy sum rate in two way untrusted relaying"
    - "joint relay and jammer selection improves the physical layer security in the face of csi feedback delays"
    - "wireless powered relays in cooperative communications time switching relaying protocols and throughput analysis"
    - "security versus reliability analysis of opportunistic relaying"
    - "secure communication with a wireless powered friendly jammer"
    - "secure beamforming for mimo two way communications with an untrusted relay"

Connected through hyperedge HE-5 (induced by source paper "secure two way communication via a wireless powered untrusted relay and friendly jammer"):
  with members:
    - "optimal power allocation and secrecy sum rate in two way untrusted relaying"
    - "wireless powered relays in cooperative communications time switching relaying protocols and throughput analysis"
    - "wireless networks with rf energy harvesting a contemporary survey"
    - "secure communication with a wireless powered friendly jammer"
    - "a new look at dual hop relaying performance limits with hardware impairments"

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)