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: "an adaptive secret key directed cryptographic scheme for secure transmission in wireless sensor networks"
  Abstract: Wireless Sensor Networks (WSNs) are memory and bandwidth limited networks whose main goals are to maximize the network lifetime and minimize the energy consumption and transmission cost. To achieve these goals, dif ferent techniques of compression and clustering have been used. However, security is an open and major issue in WSNs for which different approaches are used, both in centralized and distributed WSNs' environments. This paper presents an adaptive cryptographic scheme for secure transmission of various sensitive parameters, sensed by wireless sensors to the fusion center for further processing in WSNs such as military networks. The proposed method encrypts the sensitive captured data of sensor nodes using various encryption procedures (bitxor operation, bits shuffling, and secret key based encryption) and then sends it to the fusion center. At the fusion center, the received encrypted data is decrypted for taking further necessary actions. The experimental results with complexity analysis, validate the effectiveness and feasibility of the proposed method in terms of security in WSNs.

Connected through hyperedge HE-1 (induced by source paper "a new image steganographic technique using pattern based bits shuffling and magic lsb for grayscale images"):
  with members:
    - "a novel magic lsb substitution method m lsb sm using multi level encryption and achromatic component of an image"
    - "describing colors textures and shapes for content based image retrieval a survey"
    - "a secure cyclic steganographic technique for color images using randomization"
    - "a novel image steganographic approach for hiding text in color images using hsi color model"
    - "ontology based secure retrieval of semantically significant visual contents"
    - "secure image steganography using cryptography and image transposition"

Connected through hyperedge HE-2 (induced by source paper "steganography a secure way for transmission in wireless sensor networks"):
  with members:
    - "a novel magic lsb substitution method m lsb sm using multi level encryption and achromatic component of an image"
    - "a new image steganographic technique using pattern based bits shuffling and magic lsb for grayscale images"
    - "describing colors textures and shapes for content based image retrieval a survey"
    - "a secure cyclic steganographic technique for color images using randomization"
    - "a novel image steganographic approach for hiding text in color images using hsi color model"
    - "ontology based secure retrieval of semantically significant visual contents"
    - "secure image steganography using cryptography and image transposition"
    - "on topological properties of wireless sensor networks under the q composite key predistribution scheme with on off 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.CR(Cryptography and Security)