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: "explicit solution of worst case secrecy rate for miso wiretap channels with spherical uncertainty"
  Abstract: A multiple-input single-output (MISO) wiretap channel model is considered, in which a multi-antenna source communicates with a single-antenna destination in the presence of one single-antenna eavesdropper. It is assumed that both the channel to the destination and the channel to the eavesdropper contain spherical uncertainty. The problem of finding the optimal input covariance that maximizes the worst-case secrecy rate subject to a sum power constraint is studied, and an explicit expression for the maximum worst-case secrecy rate is provided.

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"
    - "secure communication via a wireless energy harvesting untrusted relay"

Connected through hyperedge HE-2 (induced by source paper "mimo secret communications against an active eavesdropper"):
  with members:
    - "secure degrees of freedom regions of multiple access and interference channels the polytope structure"
    - "linear precoding of data and artificial noise in secure massive mimo systems"
    - "improving wireless physical layer security via exploiting co channel interference"
    - "secure massive mimo transmission with an active eavesdropper"
    - "physical layer security for massive mimo an overview on passive eavesdropping and active attacks"
    - "secure massive mimo transmission in the presence of an active eavesdropper"
    - "secure degrees of freedom of one hop wireless networks"
    - "improving physical layer secrecy using full duplex jamming receivers"

Connected through hyperedge HE-3 (induced by source paper "robust artificial noise aided transmit design for multi user miso systems with integrated services"):
  with members:
    - "safeguarding decentralized wireless networks using full duplex jamming receivers"
    - "principles of physical layer security in multiuser wireless networks a survey"
    - "physical layer multicasting by stochastic transmit beamforming and alamouti space time coding"
    - "wireless physical layer security with imperfect channel state information a survey"
    - "outage constrained robust secure transmission for miso wiretap channels"
    - "new results on multiple input multiple output broadcast channels with confidential messages"
    - "precoder design for physical layer multicasting"
    - "robust secure transmission in miso channels based on worst case optimization"

Connected through hyperedge HE-4 (induced by source paper "energy efficiency in secure multi antenna systems"):
  with members:
    - "energy efficient scheduling and power allocation in downlink ofdma networks with base station coordination"
    - "real and complex monotone communication games"
    - "on secrecy capacity of fast fading mimome wiretap channels with statistical csit"
    - "on the design of artificial noise aided secure multi antenna transmission in slow fading channels"
    - "on secrecy rate of the generalized artificial noise assisted secure beamforming for wiretap channels"
    - "framework for link level energy efficiency optimization with informed transmitter"
    - "information theoretically secret key generation for fading wireless channels"
    - "transmitter optimization for achieving secrecy capacity in gaussian mimo wiretap channels"

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)