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: "lpch and udlpch location aware routing techniques in wsns"
  Abstract: Wireless sensor nodes along with Base Station (BS) constitute a Wireless Sensor Network (WSN). Nodes comprise of tiny power battery. Nodes sense the data and send it to BS. WSNs need protocol for efficient energy consumption of the network. In direct transmission and minimum transmission energy routing protocols, energy consumption is not well distributed. However, LEACH (Low-Energy Adaptive Clustering Hierarchy) is a clustering protocol, randomly selects the Cluster Heads (CHs) in each round. However, random selection of CHs does not guarantee efficient energy consumption of the network. Therefore, we proposed new clustering techniques in routing protocols, Location-aware Permanent CH (LPCH) and User Defined Location-aware Permanent CH (UDLPCH). In both protocols, network field is physically divided in to two regions, equal number of nodes are randomly deployed in each region. In LPCH, number of CHs are selected by LEACH algorithm in first round. However in UDLPCH, equal and optimum number of CHs are selected in each region, throughout the network life time number of CHs are remain same. Simulation results show that stability period and throughput of LPCH is greater than LEACH, stability period and throughput of UDLPCH is greater than LPCH.

Connected through hyperedge HE-1 (induced by source paper "amctd adaptive mobility of courier nodes in threshold optimized dbr protocol for underwater wireless sensor networks"):
  with members:
    - "ach away cluster heads scheme for energy efficient clustering protocols in wsns"
    - "q leach a new routing protocol for wsns"
    - "heer hybrid energy efficient reactive protocol for wireless sensor networks"
    - "on modeling geometric joint sink mobility with delay tolerant cluster less wireless sensor networks"
    - "e horm an energy efficient hole removing mechanism in wireless sensor networks"
    - "divide and rule scheme for energy efficient routing in wireless sensor networks"
    - "on adaptive energy efficient transmission in wsns"
    - "ceec centralized energy efficient clustering a new routing protocol for wsns"

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.NI(Networking and Internet Architecture)