1. Maximizing Lifetime of Sensor Surveillance Systems Published : IEEE/ACM Transactions on Networking Authors : Hai Liu, Xiaohua Jia, Peng-Jun Wan, Chih-Wei Yi, S. Kami Makki, and Niki Pissinou S. Kami Makki, and Niki Pissinou

2. Outline System Model and Problem Statement System Model and Problem Statement Proposed solution Proposed solution Find Maximal Lifetime Find Maximal Lifetime Decompose Workload Matrix Decompose Workload Matrix Determine Surveillance Tree Determine Surveillance Tree Experiments and Simulations Experiments and Simulations Conclusion Conclusion

3. System Model and Problem Statement A set of targets A set of sensors Each sensor can watch at most one target at a time Each target should be watched by one sensor at anytime the lifetime of network is maximized there exists any target can not be watched by any sensor there exists any sensor can not send data to BS there exists any sensor can not send data to BS

4. Proposed solution

5. Find Maximal Lifetime (1/2)

6. Find Maximal Lifetime (2/2)

7. Decompose Workload Matrix (1/3) s1s1 t1t1 s2s2 s3s3 t2t2 t3t3 2 1 2 1 1 1 1 = ++ 1 0 0 1

9. Decompose Workload Matrix (2/3)

10. Decompose Workload Matrix (3/3) 000??? 17.230000??? 000??? 013.09990??? 0028.6972??? 11.467215.59730??? L=28.6972R=28.6972C=28.6972 28.6972 0 0 0 0 0 00 R=11.4672 11.46720 C=17.2300 17.2300 0 0 0 11.4672 R=15.5973C= 1.6327 15.5973 R= 0 0 R= 1.6327 1.6327

12. Determine Surveillance Tree f ij is proposed by LP f ij is proposed by LP let sensor i forward its outgoing data first to s 1 until flow f i1 is saturated, then switch to s 2 until the value of f i2 is met, and finally forward the last flow f il to s l

13. Experiments and Simulations (1/5)

14. Experiments and Simulations (2/5)

15. Experiments and Simulations (3/5)

16. Experiments and Simulations (4/5)

17. Experiments and Simulations (5/5)

18. Conclusion presented the maximal lifetime scheduling problem