1. Author : 1131037005 컴퓨터 공학과 김홍연 An Energy Efficient Hierarchical Clustering Algorithm for Wireless Sensor Networks. Seema Bandyopadhyay, Edward J. Coyle 1

2.  A Wireless network consisting of a large number of small sensors with low-power transceivers can be an effective tool for gathering data in a variety of environments.  Weakness of the sensor : limited energy resources. Abstract. 2 C S1 S2 S3 S4 S5 S6 S7 S8 S : sensor C : single processing center

3.  Clustering.  Sensors communicate information only to clusterheads and then the clusterheads communicate the aggregated information to the processing center, may save energy.  This paper propose a distributed, randomized clustering algorithm to organize the sensors in a wireless sensor network into clusters. Abstract. 3 Plane Cluster Head Sensor Cluster

4.  In this paper,  We propose a fast, randomized, distributed algorithm for orga-nizing the sensors in a wireless sensor network in a hierarchy of clusters with an objective of minimizing the energy spent in com-municating the information to the information processing center.  Necessity.  For wireless sensor networks with a large number of energy- constrained sensors, it is very important to design a fast algori-thm to organize sensors in clusters to minimize the energy used to communicate information from all nodes to the processing center.  Fast, Organize, Minimize energy. Introduction. 4 2 page, 3~11 lines

5. Single-level clustering algorithm. 5 Section 3 - A

6. Single-level clustering algorithm. 6 Section 3 - B

7. Single-level clustering algorithm. 7 Section 3 – B – 1) The total length of the segments from all sensor nodes. + + + + + + + =

8. Single-level clustering algorithm. 8 Section 3 – B – 1) Voronoi Cell nucleus

9. Single-level clustering algorithm. 9 Section 3 – B – 1)

10. Single-level clustering algorithm. 10 Section 3 – B – 1) (5)(6) (4)(3)

11. Single-level clustering algorithm. 11 Section 3 – B – 1)

12. Single-level clustering algorithm. 12 Section 3 – B – 1)

13. Single-level clustering algorithm. 13 Section 3 – B – 2)

14. Single-level clustering algorithm. 14 Section 3 – B – 2)

15. Single-level clustering algorithm. 15 Section 3 – B – 2)

16. Single-level clustering algorithm. 16 Section 3 – C

17.  Simulation Experiments and Results. Single-level clustering algorithm. 17 Section 3 – C

18. Hierarchical clustering algorithm. 18 Section 4 Level 3 Level 2 Level 1

19. Hierarchical clustering algorithm. 19 Section 4 - A

20. Hierarchical clustering algorithm. 20 Section 4 - B

21. Hierarchical clustering algorithm. 21 Section 4 - B

22. Hierarchical clustering algorithm. 22 Section 4 - B

23. Hierarchical clustering algorithm. 23 Section 4 - B

24.  Optimal parameters for the algorithm.  The expected total cost of communicating information from sensors to the processing center in the clustered environment is given by, Hierarchical clustering algorithm. 24 Section 4 - B Eq (6) Eq (16) Eq (14) Eq (15)

25. Hierarchical clustering algorithm. 25 Section 4 - B Eq (8)

26. Hierarchical clustering algorithm. 26 Section 4 - B Eq (12)

27.  Numerical Results and Simulations. Hierarchical clustering algorithm. 27 Section 4 - C