During the 15 years, wireless sensor networks have witnessed significant growth and development in academia and industry. Many researchers have been interested in solving challenging problems that span all the layers of the protocol stack of sensor networking systems. Journals, conferences, and workshops have launched to cover innovative research and practice in this promising and rapidly advancing field. This book provides the sensor networks community a comprehensive reference on findings on a variety of topics in wireless sensor networks. This book relates to the second volume and focuses on the advanced topics and applications of wireless sensor networks. The second volume has all application-specific and non-conventional sensor networks, emerging techniques and advanced topics that are not as matured as what is covered in the first volume. Thus, the second volume deals with 3-D, underground, underwater, body-mounted, and societal networks. Following Donald E. Knuth's elegant strategy to focus on several important fields (The Art of Computer Programming: Fundamental Algorithms, 1997), this volume includes up-to-date research work spanning such topics as stochastic modeling, barrier and spatiotemporal coverage, tracking, estimation, counting, coverage and localization in 3-D sensor networks, topology control and routing in 3-D sensor networks, underground and underwater sensor networks, multimedia and body sensor networks, and social sensing. This book will be an excellent source of information for graduate students majoring in computer science, computer engineering, electrical engineering, or any related discipline. Furthermore, computer scientists, researchers, and practitioners in both academia and industry will find this book useful and interesting.