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: "heer hybrid energy efficient reactive protocol for wireless sensor networks"
  Abstract: Wireless Sensor Networks (WSNs) consist of numerous sensors which send sensed data to base station. Energy conservation is an important issue for sensor nodes as they have limited power. Many routing protocols have been proposed earlier for energy efficiency of both homogeneous and heterogeneous environments. We can prolong our stability and network lifetime by reducing our energy consumption. In this research paper, we propose a protocol designed for the characteristics of a reactive homogeneous WSNs, HEER (Hybrid Energy Efficient Reactive) protocol. In HEER, Cluster Head(CH) selection is based on the ratio of residual energy of node and average energy of network. Moreover, to conserve more energy, we introduce Hard Threshold (HT) and Soft Threshold (ST). Finally, simulations show that our protocol has not only prolonged the network lifetime but also significantly increased stability period.

Connected through hyperedge HE-1 (induced by source paper "survey on variants of distributed energy efficient clustering protocols in heterogeneous wireless sensor network"):
  with members:
    - "eddeec enhanced developed distributed energy efficient clustering for heterogeneous wireless sensor networks"
    - "hybrid deec towards efficient energy utilization in wireless sensor networks"
    - "beenish balanced energy efficient network integrated super heterogeneous protocol for wireless sensor networks"
    - "maximizing the lifetime of multi chain pegasis using sink mobility"

Connected through hyperedge HE-2 (induced by source paper "an energy efficient decoding scheme for wireless body area sensor networks"):
  with members:
    - "energy efficient mac protocols in wireless body area sensor networks a survey"
    - "e horm an energy efficient hole removing mechanism in wireless sensor networks"
    - "divide and rule scheme for energy efficient routing in wireless sensor networks"
    - "density controlled divide and rule scheme for energy efficient routing in wireless sensor networks"
    - "towards lp modeling for maximizing throughput and minimizing routing delay in proactive protocols in wireless multi hop networks"
    - "srp ms a new routing protocol for delay tolerant wireless sensor networks"
    - "aid an energy efficient decoding scheme for ldpc codes in wireless body area sensor networks"
    - "on adaptive energy efficient transmission in wsns"

Connected through hyperedge HE-3 (induced by source paper "modeling and evaluating performance of routing operations in reactive routing protocols"):
  with members:
    - "evaluating and comparing probability of path loss in dsdv olsr and dymo at 802 11 and 802 11p"
    - "ach away cluster heads scheme for energy efficient clustering protocols in wsns"
    - "evaluating wireless reactive routing protocols with linear programming model for wireless ad hoc networks"
    - "on energy efficiency and delay minimization in reactive protocols in wireless multi hop networks"
    - "e horm an energy efficient hole removing mechanism in wireless sensor networks"
    - "density controlled divide and rule scheme for energy efficient routing in wireless sensor networks"
    - "towards lp modeling for maximizing throughput and minimizing routing delay in proactive protocols in wireless multi hop networks"
    - "on adaptive energy efficient transmission in wsns"

Connected through hyperedge HE-4 (induced by source paper "imod leach improved modified leach protocol for wireless sensor networks"):
  with members:
    - "ach away cluster heads scheme for energy efficient clustering protocols in wsns"
    - "advanced leach a static clustering based heteroneous routing protocol for wsns"
    - "modleach a variant of leach for wsns"
    - "energy efficient mac protocols in wireless body area sensor networks a survey"
    - "east energy efficient adaptive scheme for transmission in wireless sensor networks"
    - "e horm an energy efficient hole removing mechanism in wireless sensor networks"
    - "density controlled divide and rule scheme for energy efficient routing in wireless sensor networks"
    - "towards lp modeling for maximizing throughput and minimizing routing delay in proactive protocols in wireless multi hop networks"

Connected through hyperedge HE-5 (induced by source paper "measuring fatigue of soldiers in wireless body area sensor networks"):
  with members:
    - "eddeec enhanced developed distributed energy efficient clustering for heterogeneous wireless sensor networks"
    - "hybrid deec towards efficient energy utilization in wireless sensor networks"
    - "q leach a new routing protocol for wsns"
    - "energy efficient mac protocols in wireless body area sensor networks a survey"
    - "density controlled divide and rule scheme for energy efficient routing in wireless sensor networks"
    - "adaptive reliable medium access control protocol for wireless body area networks"
    - "energy efficient sleep awake aware eesaa intelligent sensor network routing protocol"
    - "ubiquitous healthcare in wireless body area networks"

Connected through hyperedge HE-6 (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"
    - "on modeling geometric joint sink mobility with delay tolerant cluster less wireless sensor networks"
    - "lpch and udlpch location aware routing techniques in wsns"
    - "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"

Connected through hyperedge HE-7 (induced by source paper "m gear gateway based energy aware multi hop routing protocol for wsns"):
  with members:
    - "ach away cluster heads scheme for energy efficient clustering protocols in wsns"
    - "q leach a new routing protocol for wsns"
    - "on modeling geometric joint sink mobility with delay tolerant cluster less wireless sensor networks"
    - "divide and rule scheme for energy efficient routing in wireless sensor networks"
    - "maximizing the lifetime of multi chain pegasis using sink mobility"
    - "on adaptive energy efficient transmission in wsns"
    - "identifying design requirements for wireless routing link metrics"
    - "interference and bandwidth adjusted etx in wireless multi hop networks"

Connected through hyperedge HE-8 (induced by source paper "dreem me distributed regional energy efficient multi hop routing protocol based on maximum energy in wsns"):
  with members:
    - "eapess an adaptive transmission scheme in wireless sensor networks"
    - "eddeec enhanced developed distributed energy efficient clustering for heterogeneous wireless sensor networks"
    - "q leach a new routing protocol for wsns"
    - "z sep zonal stable election protocol for 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"
    - "optimal number of cluster head selection for efficient distribution of sources in 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)