استاد راهنما: دکتر علی موقررحیمآبادی استاد مشاور: دکتر...
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بررسی و ارزیابی پوشش k تایی در شبکه‌های حسگر Study and Evaluation of k-Coverage in Sensor Networks. استاد راهنما: دکتر علی موقررحیمآبادی استاد مشاور: دکتر محمد قدسی مریم بوشهریان دیماه 1385. فهرست مطالب. شبکه‌های حسگر پارامترهای یک شبکه‌ی حسگر اهداف گوناگون در شبکه‌های حسگر - PowerPoint PPT PresentationTRANSCRIPT
بررسی و ارزیابی تایی در k پوشششبکه های حسگر
Study and Evaluation ofk-Coverage in Sensor Networks
استاد‌راهنما:دکتر‌علی‌موقررحیم‌آبادیاستاد‌مشاور:دکتر‌محمد‌قدسی
مریم‌بوشهریان1385دیماه
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فهرست‌مطالبشبکه‌های‌حسگر•پارامترهای‌یک‌شبکه‌ی‌حسگر•اهدافگوناگوندرشبکههایحسگر•مسئله‌ی‌پوشش•مسائل‌مختلف‌در‌پوشش‌حسی•پوشش‌با‌مصرف‌انرژی‌بهینه•الگوریتم‌های‌ارائه‌شده‌برای‌باالبردن‌عمر‌شبکه•شرایط‌ويژه‌ی‌مسئله‌مصرف‌بهینه‌انرژی•روش‌پیشنهادی‌و‌زمان‌بندی•
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شبکه‌ی‌حسگرمجموعه‌ای‌از‌تعداد‌بسیار‌زیادی‌حسگر‌با‌تراکم•
باالهدف:در‌ارتباط‌با‌یکدیگر‌یک‌وظیفه‌ی‌حسی‌را•
در‌یک‌مکان‌ایجاد‌کنند.
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(1پارامترهای‌یک‌شبکه‌ی‌حسگر)
ساختار‌شبکه•مسطح–سلسله‌مراتبی–
نحوه‌ی‌چینش‌حسگرها•تصادفی–توزیع‌های‌مختلف‌آماری‌مانند‌پواسون–
مدل‌ردیابی•
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(2پارامترهای‌یک‌شبکه‌ی‌حسگر)
ناحیه‌ی‌حسی•بعدی2–بعدی3–
محدوده‌ی‌ارسالی•هم‌گامی‌زمان•مدل‌خرابی•تحرک‌حسگرها•اطالعات‌مکانی•
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اهدافگوناگوندرشبکههایحسگر
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مسئله‌ی‌پوشش
بررسی‌میزان‌احاطه‌ی‌حسگرها‌بر‌منطقه‌ی•مورد‌نظر
تعاریف:•نقطه‌ی‌کور–پوشش‌منطقه‌ای–پوشش‌نقطه‌ای–پوشش‌حصاری–
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مسائل‌مختلف‌در‌پوشش‌حسیتعداد‌حسگرهای‌کمینه•تاییkبررسی‌پوشش•تاییkدر‌پوششkتعیین•بعدی3پوشش‌در‌فضای•اتصال‌و‌پوشش•حرکت‌حسگرها‌به‌منظور‌تامین‌پوشش)تکی‌یا•
k)تاییپوشش‌با‌مصرف‌انرژی‌بهینه•
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پوشش‌با‌مصرف‌انرژی‌بهینهچینش‌حسگرها‌محدودیت‌دارد:•
هزینه‌بر‌است.–در‌همه‌ی‌زمان‌ها‌انجام‌پذیر‌نیست.–
چینش‌خیلی‌وقت‌ها‌به‌صورت‌متراکم‌انجام•می‌شود.
حسگرها‌محدودیت‌های‌زیادی‌دارند.•عمر‌مفید–محدودیت‌منبع‌انرژی–
طوالنی‌کردن‌عمر‌شبکه‌بدون‌از‌دست‌دادن•پوشش‌مطلوب،اهمیت‌دارد.
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مثال
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مثال
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مثال
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پوشش‌با‌هدف‌افزایش‌دوره‌ی‌حیات‌شبکه
هدف:باال‌بردن‌طول‌عمر‌یک‌شبکه‌ی‌حسگر،با•در‌نظر‌گرفتن‌پوشش‌اولیه‌ی‌آن
فعال
واحد حسی فعال
گیرنده ی فعال
غیرفعال )خواب(
مراقبشنوا
کامال‌غیرفعال
حس‌کننده
خاموش‌یا‌روشن‌کردن‌واحد‌حسی
خاموش‌یا‌روشن‌کردن‌پردازنده
خاموش‌یا‌روشن‌کردن‌پردازنده
خاموش‌یا‌روشن‌کردن‌پردازنده
خاموش‌یا‌روشن‌کردن‌واحد‌حسی
خاموش‌یا‌روشن‌کردن‌گیرنده
خاموش‌یا‌روشن‌کردن‌گیرنده
خاموش‌یا‌روشن‌کردن‌واحد‌حسی
خاموش‌یا‌روشن‌کردن‌گیرنده
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الگوریتم‌های‌ارائه‌شده‌برای‌شبکه باالبردن‌عمر‌شبکه ویژگی
از الگوریتم اطالعفاصله‌ی
حسگرها بین
مکان از اطالعحسگرها
تحرکهم‌گامی
یزمان
محدوده ی
حسی
منطقه‌یحسی
تراکم باالی
حسگرها
چینش حسگرها
ساختار شبکه
یک‌نواخت
بعدی2 یک‌نواخت مسطح RIS
یک‌نواخت
بعدی2 - مسطحSponsered
Sector
- بعدی2 - مسطح MSNL
یک‌نواخت
بعدی2 یک‌نواخت مسطح LDAS
- - یک‌نواخت مسطح PEAS
یک‌نواخت
بعدی2 - مسطح OGDC
یک‌نواخت
بعدی2 - مسطح CCP
- - - مسطح ASCENT
- - یک‌نواخت مسطح PECAS
- - -سلسله‌مرات
بیLEACH
- - -سلسله‌مرات
بیE-LEACH
- - -سلسله‌مرات
بیESS
یک‌نواخت
بعدی2 پواسونسلسله‌مرات
بیLDS
یک‌نواخت
بعدی2 پواسونسلسله‌مرات
بیBS
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شرایط‌ويژه‌ی‌مسئله‌مصرف‌بهینه‌انرژی
اجرای‌الگوریتم‌به‌صورت‌مرکزی‌بسیار‌هزینه‌بر•و‌در‌مواردی‌غیرممکن‌است.
واحدهای‌پردازش)حسگرها(ضعیف‌هستند:•پردازنده–حافظه–انرژی–برد‌انتقال‌اطالعات–
-NPبسیاری‌از‌مسائل‌مطرح‌در‌این‌زمینه•Complete.هستند
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روش‌پیشنهادیدر‌صورت‌امکان،ارائه‌ی‌یک‌الگوریتم‌بهینه‌یا•
تایی‌با‌هدفkنزدیک‌به‌بهینه‌در‌زمینه‌ی‌پوشش‌افزایش‌دوره‌ی‌حیات‌شبکه
پیاده‌سازی‌الگوریتم‌و‌شبیه‌سازی‌آن•NS-2استفاده‌از‌ابزارهای‌شبیه‌سازی‌شبکه‌مانند–
پیاده‌سازی‌الگوریتم‌به‌صورت‌مستقیم‌با‌کمک–زبان‌های‌برنامه‌سازی
مقایسه‌ی‌نتایج‌با‌کارهای‌مرتبط•
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زمان‌بندی‌مورد‌نظر
دی بهمن اسفند فروردین
اردیبهشت
خرداد تیر مرداد
بررسی‌مقاالت‌و‌شده‌کارهای‌انجام
نوشتن‌پایان‌نامه‌و‌دفاع
ارائه‌یک‌روش‌بهینه‌یا‌نزدیک‌به‌بهینه‌و‌پیاده‌سازی‌آن
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منابع‌اصلی1. S. Kumar, T. H. Lai, J. Balogh, “On K-Coverage in a Mostly Sleeping Sensor Network,” in
Proceedings of the 10th Annual International Conference on Mobile Computing and Networking (Mobicom’04), pages 144–158, 2004.
2. D. Tian, N. D. Georganas, “A Coverage-Preserving Node Scheduling Scheme for Large Wireless Sensor Networks,” in Proceedings of the 1st ACM International Workshop on Wireless Sensor Networks and Applications (WSNA’02), pages 32–41, 2002.
3. P. Berman, G. Calinescu, C.Shah, A. Zelikovsly, “Efficient Energy Management in Sensor Networks,” in Y. Xiao and Y. Pan, editors, Ad Hoc and Sensor Networks, Nova Science Publishers, 2005.
4. K. Wu, Y. Gao, F. Li, Y. Xiao, “Lightweight Deployment-aware Scheduling for Wireless Sensor Networks,” ACM/Kluwer Mobile Networks and Applications (MONET) Special Issue on Energy Constraints and Lifetime Performance in Wireless Sensor Networks, 10(6):837–852, December 2005.
5. F. Ye, G. Zhong, J. Cheng, S. Lu, L. Zhang, “Peas: A Robust Energy Conserving Protocol for Long-lived Sensor Networks,” in Proceedings of the 23rd International Conference on Distributed Computing Systems (ICDCS ’03), pp. 28–37, 2003.
6. H. Zhang, J. C. Hou, “Maintaining Sensing Coverage and Connectivity in Large Sensor Networks,” in Proceedings of NSF International Workshop on Theoretical and Algorithmic Aspects of Sensor, Ad Hoc Wireless, and Peer-to-Peer Networks, 2004. invited paper.
7. X. Wang, G. Xing, Y. Zhang, C. Lu, R. Pless, C. Gill, “Integrated Coverage and Connectivity Configuration in Wireless Sensor Networks,” in Proceedings of the 1st International Conference on Embedded Networked Sensor Systems (Sensys ’03), pp. 28–39, 2003.
8. A. Cerpa, D. Estrin, “Ascent: Adaptive Self-configuring Sensor Networks Topologies,” in Proceedings of IEEE INFOCOM 2002, New York, NY, June 2002.
19
منابع‌اصلی9. C. Gui, P. Mohapatra, “Power Conservation and Quality of Surveillance in Target Tracking
Sensor Networks,” in Proceedings of the 10th Annual International Conference on Mobile Computing and Networking (Mobicom’04), pp. 129–143, 2004.
10. W. R. Heinzelman, A. Chandrakasan, H. Balakrishnan, “Energy-efficient Communication Protocols for Wireless Microsensor Networks,” in Proceedings of Hawaaian International Conference on Systems Science, January 2000.
11. W. Heinzelman, A. Chandrakasan, H. Balakrishnan, “An Application-specific Protocol Architecture for Wireless Microsensor Networks,” IEEE Transactions on Wireless Communications, 1(4):660–670, October 2002.
12. T. He, S. Krishnamurthy, J. A. Stankovic, T. Abdelzaher, L. Luo, R. Stoleru, T. Yan, L. Gu, J. Hui, B. Krogh, “Energy-efficient Surveillance System Using Wireless Sensor Networks,” in Proceedings of the 2nd International Conference on Mobile Systems, Applications, and Services (MobiSys’04), pp. 270–283, 2004.
13. J. Deng, Y. S. Han, W. B. Heinzelman, P. K. Varshney, “Scheduling Sleeping Nodes in High Density Cluster-based Sensor Networks,” ACM/Kluwer Mobile Networks and Applications (MONET) Special Issue on Energy Constraints and Lifetime Performance in Wireless Sensor Networks, 2004. to appear.
14. J. Deng, Y. S. Han, W. B. Heinzelman, P. K. Varshney, “Balanced Energy Sleep Scheduling Scheme for High Density Cluster-based Sensor Networks,” in Proc. of the 4th Workshop on Applications and Services in Wireless Networks (ASWN’04), 2004.
20
منابع‌دیگر)ادامه(1. A. Boukerche, X. Fei, “Coverage Protocols For Detecting Fully Sponsored Sensors In Wireless Sensor Networks,”
in Proceedings of the 3rd ACM International Workshop on Performance Evaluation of Wireless Ad-hoc, Sensor and Ubiquitous Networks (PE-WASUN’06), pp. 58-65, Oct. 2006.
2. A. Cerpa, D. Estrin, “Ascent: Adaptive Self-configuring sEnsor Networks Topologies,” in Proceedings of IEEE INFOCOM 2002, New York, New York, USA, vol. 3(3), pp. 272-285, Aug. 2002.
3. A. Howard, M. J. Mataric, G. S. Sukhatme, “An Incremental Self-Deployment Algorithm for Mobile Sensor Networks,” Autonomous Robots, Special Issue on Intelligent Embedded Systems, Sep. 2002.
4. A. Howard, M. J. Mataric, G. S. Sukhatme, “Mobile Sensor Networks Deployment Using Potential Fields: A Distributed, Scalable Solution to the Area Coverage Problem,” the 6th International Symposium on Distributed Autonomous Robotics Systems, Jun. 2002.
5. A. Mainwaring, J. Polastre, R. Szewczyk, D. Culler, J. Anderson, "Wireless Sensor Networks for Habitat Monitoring," in Proceedings of the 1st ACM international workshop on Wireless sensor networks and applications, Atlanta, Georgia, USA, pp. 88-97, 2002.
6. B. Chen, K. Jamieson, H. Balakrishnan, R. Morris, “Span: An Energy-efficient Coordination Algorithm for Topology Maintenance in Ad hoc Wireless Networks,” Wireless Networks, vol. 8(5), pp. 481–494, Sep. 2002.
7. B. Liu, P. Brass, O. Dousse, P. Nain, D. Towsley, “Mobility Improves Coverage of Sensor Networks,” in Proceedings of the 6th ACM International Symposium on Mobile Ad hoc Networking and Computing , Urbana-Champaign, Illinois, USA, pp. 300-308. 2005.
8. C. Gui, P. Mohapatra, “Power Conservation and Quality of Surveillance in Target Tracking Sensor Networks,” in Proceedings of the 10th Annual International Conference on Mobile Computing and Networking (Mobicom’04), Philadelphia, Pennsylvania, USA, pp. 129–143, 2004.
9. C. Trefftz, J. Szakas, “Parallel Algorithms to Find the Voronoi Diagram and the Order-k Voronoi Diagram,” in Proceedings of International Parallel and Distributed Processing Symposium, 4 pp., Apr. 2003.
21
منابع‌دیگر)ادامه(10. D. Lee, “On k-Nearest Neighbor Voronoi Diagrams in the Plane,” IEEE Transactions on Computers, vol. c-31(6),
pp. 478-487, Jun. 1982.
11. D. Tian and N. D. Georganas, “A Coverage-Preserving Node Scheduling Scheme for Large Wireless Sensor Networks,” in Proceedings of the 1st ACM International Workshop on Wireless Sensor Networks and Applications (WSNA’02), Atlanta, Georgia, USA, pp. 32–41, 2002.
12. E. Onur, C. Ersoy, H. Delic, “Finding Sensing Coverage and Breach Paths in Wireless Sensor Networks,” in Proceedings of the IEEE 12th Signal Processing and Communications Applications Conference, pp. 692-695, Apr. 2004.
13. F. Ye, G. Zhong, J. Cheng, S. Lu, L. Zhang, “Peas: A Robust Energy Conserving Protocol for Long-lived Sensor Networks,” in Proceedings of the 23rd International Conference on Distributed Computing Systems (ICDCS’03), pp. 28–37, 2003.
14. G. J. Pottie, W. J. Kaiser, "Wireless Integrated Network Sensors," Communications of the ACM, vol. 43(5), pp. 51–58, May 2000.
15. G. Wang, G. Cao, T. L. Porta, “Movement-Assisted Sensor Deployment,” the 23rd AnnualJoint Conference of the IEEE Computer and Communications Societies (INFOCOM'04), vol. 4, pp. 2469-2479, Mar. 2004.
16. G. Xing, C. Lu, R. Pless, and J. A. O’Sullivan, “Co-Grid: an Efficient Coverage Maintenance Protocol for Distributed Sensor Networks,” in Proceedings of IPSN’04, Berkeley, California, USA, Apr. 2004.
17. G. Xing, X. Wang, Y. Zhang, C. Lu, R. Pless, C. Gill, “Integrated Coverage and Connectivity Configuration for Energy Conservation in Sensor Networks,” ACM Transactions on Sensor Networks, vol. 1(1), pp. 36–72, 2005.
18. H. Gupta, Z. Zhou, S. R. Das, Q. Gu, “Connected Sensor Cover: Self-Organization of Sensor Networks for Efficient Query Execution,” IEEE/ACM Transactions on Networking, vol. 14(1), Feb. 2006.
19. H. Karl, A. Willig, "A Short Survey of Wireless Sensor Networks," TKN Technical Report Series, Oct. 2003.
22
منابع‌دیگر)ادامه(20. H. Zhang, J. C. Hou, “Maintaining Sensing Coverage and Connectivity in Large Sensor Networks,” in
Proceedings of NSF International Workshop on Theoretical and Algorithmic Aspects of Sensor, Ad Hoc Wireless, and Peer-to-Peer Networks, invited paper, 2004.
21. I. F. Akyildiz, W. Su, Y. Sankarasubramaniam, E. Cayirci, “Wireless Sensor Networks: a Survey,” Computer Networks 38, pp.393–422, 2002.
22. I. Vasilescu, K. Kotay, D. Rus, M. Dunbabin, P. Corke, "Data Collection, Storage, and Retrieval with an Underwater Sensor Network," in Proceedings of the 3rd International Conference on Embedded Networked Sensor Systems, San Diego, California, USA, pp.154–165, 2005.
23. J. Deng, Y. S. Han, W. B. Heinzelman, P. K. Varshney, “Scheduling Sleeping Nodes in High Density Cluster-based Sensor Networks,” ACM/Kluwer Mobile Networks and Applications (MONET) Special Issue on ”Energy Constraints and Lifetime Performance in Wireless Sensor Networks”, vol. 10(6), 835-835, Dec. 2005.
24. J. Elson, D. Estrin, “Time Synchronization for Wireless Sensor Networks,” in Proceedings of the 15th International Parallel & Distributed Processing Symposium (IPDPS’01), pp. 1965-1970, Apr. 2001.
25. J. Jiang, Z. Song, H. Zhang, and W. Dou, “Voronoi-Based Improved Algorithm for Connected Coverage Problem in Wireless Sensor Networks,” Lecture notes in computer science, vol. 3824, pp. 224-233, Dec. 2005.
26. J. M. Kahn, R. H. Katz, K. S. J. Pister, "Next century challenges: mobile networking for Smart Dust," in Proceedings of the 5th annual ACM/IEEE international conference on Mobile computing and networking, Seattle, Washington, USA, pp. 271-278, 1999.
27. K. Chakrabarty, S. Iyengar, H. Qi, E. Cho, “Grid Coverage for Surveillance and Target Location in Distributed Sensor Networks,” IEEE Transactions on Computers, vol. 51(12), pp. 1448-1453, Dec. 2002.
28. K. Wu, Y. Gao, F. Li, Y. Xiao, “Lightweight Deployment-aware Scheduling for Wireless Sensor Networks,” ACM/Kluwer Mobile Networks and Applications (MONET) Special Issue on “Energy Constraints and Lifetime Performance in Wireless Sensor Networks”, 10(6), pp. 837–852, Dec. 2005.
29. M. Bagheri, M, Hafeeda, H. Ahmadi, “A Near Optimal K-Coverage Algorithm for Large-Scale Sensor Networks”, Technical Report, 2006.
23
منابع‌دیگر)ادامه(30. M. I. Shamos, D. Hoey, "Closest-Point Problems," in Proceedings of 16th IEEE Symposium on Foundations of
Computer Science, pp. 151-162, Oct. 1975.
31. M. K. Watfa, S. Commuri, “A Coverage Algorithm in 3D Wireless Sensor Networks”, in 1st International Symposium on Wireless Pervasive Computing, 6 pp., Jan. 2006.
32. M. K. Watfa, S. Commuri, "Optimal 3-Dimensional Sensor Deployment Strategy," 3rd IEEE Consumer Communications and Networking Conference (CCNC'06), vol. 2, pp. 892-896, Jan. 2006.
33. M. K. Watfa, S. Commuri, "Optimality Measures for Coverage in 3D Wireless Sensor Networks," 1st International Symposium on Wireless Pervasive Computing, 6 pp., 2006.
34. M. Marengoni, B. Draper, A. Hanson, R. Sitaraman, “A System to Place Observers on a Polyhedral Terrain in Polynomial Time,” Image and Vision Computing, vol. 18, pp. 773–780, 2000.
35. M. X. Cheng, L. Ruan, W. Wu, “Achieving Minimum Coverage Breach under Bandwidth Constraints in Wireless Sensor Networks,” IEEE Publications, pp. 2638-2645, 2005.
36. N. Bulusu, J. Heidemann, D. Estrin, “GPS-less low cost outdoor localization for very small devices,” IEEE Personal Communications Magazine, vol. 7(5), pp. 28–34, Oct. 2000.
37. N. Bulusu, J. Heidemann, D. Estrin, T. Tran, “Self-configuring Localization Systems: Design and Experimental Evaluation,” ACM Transactions on Embedded Computing Systems (TECS), vol. 3(1), pp. 24-60, Feb. 2004.
38. P. Berman, G. Calinescu, C. Shah, A. Zelikovsly, “Efficient Energy Management in Sensor Networks,” in Y. Xiao and Y. Pan, editors, Ad Hoc and Sensor Networks, Nova Science Publishers, 2005.
39. P. Berman, G. Calinescu, C. Shah, A. Zelikovsky, “Power Efficient Monitoring Management in Sensor Networks,” in Proceedings of IEEE Wireless Communications and Networking Conference (WCNC’04), vol. 4, pp. 2329-2334, Mar. 2004.
40. P. J. De Rezende, R. B. Westrupp, “An optimal algorithm to construct all Voronoi diagrams for knearest neighbor search in T2,” in Proceedings of XII Brazilian Symposium on Computer Graphics and Image Processing, Campinas, Brazi, pp. 7-15, 1999.
24
منابع‌دیگر)ادامه(41. R. Holman, J. Stanley, T. Ozkan-Haller, "Applying Video Sensor Networks to Nearshore Environment
Monitoring," IEEE Pervasive Computing, 2003.
42. S. Kumar, T. H. Lai, A. Arora, “Barrier Coverage with wireless Sensors,” in Proceedings of the 11th Annual International Conference on Mobile computing and networking, Cologne, Germany, pp. 284-298, 2005.
43. S. Kumar, T. H. Lai, J. Balogh, “On K-Coverage in a Mostly Sleeping Sensor Network,” in Proceedings of the 10th Annual International Conference on Mobile Computing and Networking (MOBICOM’04), Philadelphia, Pennsylvania, USA, pp. 144–158, Sep. 2004.
44. S. Megerian, F. Koushanfar, M. Potkonjak, M. B. Srivastava, “Worst and Best-Case Coverage in Sensor Networks,” IEEE Transactions on Mobile Comptuing, vol. 4(1), pp. 84-92, Jan./Feb. 2005.
45. S. Meguerdichian, F. Koushanfar, M. Potkonjak, and S. M., “Coverage Problems in Wireless Ad-hoc Sensor Networks,” in Proceedings of IEEE INFOCOM’01, Apr. 2001.
46. S. Slijepcevic and M. Potkonjak, “Power Efficient Organization of Wireless Sensor Networks,” IEEE International Conference on Communications (ICC’01), vol. 2, pp. 472-476, Jun. 2001.
47. S. Yang, F. Dai, M. Cardei, J. Wu, “On Multiple Point Coverage in Wireless Sensor Networks,” in Proceedings of IEEE International Conference on Mobile Ad-hoc and Sensor Systems (MASS’05), Washington, Washington D.C., USA, 8 pp., Nov. 2005.
48. T. T. Hsieh, "Using sensor networks for highway and traffic applications," IEEE Potentials, vol. 23(2), pp. 13–16, May 2004.
49. X. Wang, G. Xing, Y. Zhang, C. Lu, R. Pless, and C. Gill, “Integrated Coverage and Connectivity Configuration in Wireless Sensor Networks,” in Proceedings of the 1st International Conference on Embedded Networked Sensor Systems (Sensys’03), pages 28–39, Nov. 2003.
50. X. Y. Li, P. J. Wan, O. Frieder, “Coverage in Wireless Ad Hoc Sensor Networks,” IEEE Transactions on Computers, vol. 52(6), Jun. 2003.
25
منابع‌دیگر)ادامه(51. Y. Huang and Y. Tseng, “The Coverage Problem in a Wireless Sensor Network,” in Proceedings ACM
International Conference on Wireless Sensor Networks and Applications, San Diego, California, USA, Sep. 2003.
52. Y. Zou, K. Chakrabarty, “Sensor Deployment and Target Localization based on Virtual Forces,” IEEE 22nd Annual Joint Conference of the IEEE Computer and Communications Societies (INFOCOM'03), vol.2 1293-1303, Apr. 2003.
53. Z. Zhou, S. Das, and H. Gupta, “Connected K-Coverage Problem in Sensor Networks,” in Proceedings of International Conference on Computer Communications and Networks (ICCCN’04), Chicago, Illinois, USA, Oct. 2004.