About me

I am a postdoctoral scholar at Department of Computer Science and Engineering of University of California, San Diego. I'm working with Prof. Rajesh Gupta.

Research

NOTE: Will be updated soon

My current research interest is in the use of controlled mobility for data collection applications in wireless sensor networks.

Collecting data from spatially distributed sensors is a generic form of sensor network applications. Multihop forwarding approach has been broadly used for this purpose, but it can be inefficient in terms of energy consumption especially when the nodes are deployed sparsely. On the other hand, using a mobile device (often called a "data mule") to traverse the sensor field and collect data from each sensor is an alternative approach. This data mule approach significantly reduces energy consumption at each node. However, a downside of this approach is an increased data delivery latency, and thus we should optimize the motion of data mule so that we can minimize the latency.

To optimize the motion of data mule, we have devised a novel formulation of the problem, which we call the Data Mule Scheduling (DMS) problem. One of the major benefits of the DMS problem framework is that it can handle various assumptions on the mobility and communication capabilities of data mule in a very structured way. We have analyzed the computational complexity of the DMS problem for different mobility cases and designed exact/approximation/heuristic algorithms. We have also considered an extension of the DMS problem for the hybrid case of multihop forwarding and data mule.

Publications

Thesis
"Controlled Mobility in Sensor Networks" [slides]
Ryo Sugihara,
University of California, San Diego, Jun. 2009
Journal papers
"Optimal Speed Control of Mobile Node for Data Collection in Sensor Networks"
Ryo Sugihara and Rajesh K. Gupta,
in IEEE Transactions on Mobile Computing, vol. 9, no. 1, pp. 127-139, Jan. 2010
"Programming Models for Sensor Networks: A Survey"
Ryo Sugihara and Rajesh K. Gupta,
in ACM Transactions on Sensor Networks, vol. 4, issue 2, Mar. 2008
(old version as UCSD Technical Report, CS2007-0881, Jan. 2007)
Conference papers
"Optimizing Energy-Latency Trade-off in Sensor Networks with Controlled Mobility"
Ryo Sugihara and Rajesh K. Gupta,
in INFOCOM 2009 Mini-conference, pp. 2566-2570,
Rio de Janeiro, Brazil, Apr. 2009
(long version as UCSD Technical Report, CS2008-0932, Nov. 2008)
"Improving the Data Delivery Latency in Sensor Networks with Controlled Mobility"
Ryo Sugihara and Rajesh K. Gupta,
in 4th IEEE International Conference on Distributed Computing in Sensor Systems (DCOSS), LNCS 5067, pp. 386-399,
Santorini island, Greece, Jun. 2008
(Best paper in Systems track [photos])
"Scheduling under Location and Time Constraints for Data Collection in Sensor Networks"
Ryo Sugihara and Rajesh K. Gupta,
in 28th IEEE Real-Time Systems Symposium (RTSS) (work-in-progress session),
Tucson, Dec. 2007
"Poster Abstract: Accuracy-aware Data Modeling in Sensor Networks" [poster],
Ryo Sugihara and Andrew A. Chien,
in 3rd ACM Conference on Embedded Networked Sensor Systems (SenSys), pp. 282-283,
San Diego, Nov. 2005
Technical reports
"Data Mule Scheduling in Sensor Networks: Scheduling under Location and Time Constraints"
Ryo Sugihara and Rajesh K. Gupta,
UCSD Technical Report, CS2007-0911, Oct. 2007
"An Efficient General-Purpose Mechanism for Data Gathering with Accuracy Requirement in Wireless Sensor Networks"
Ryo Sugihara and Andrew A. Chien,
UCSD Technical Report, CS2006-0854, Apr. 2006
Selected publications before coming to UCSD
"Practical Capacity of Digital Watermark",
Ryo Sugihara,
in 4th Intl. Information Hiding Workshop, LNCS 2137, pp. 316-329,
Pittsburgh, May 2001
"Theoretical and Experimental Evaluation of Reliability on Video Watermarking",
Ryo Sugihara,
in Symposium on Cryptography and Information Security,
Okinawa, Japan, Jan. 2000 (in Japanese)
"Neuromagnetic Fields during Motor Imagery",
Ryo Sugihara, Yoshiaki Kikuchi, Hiroaki Kawamichi, Tatsu Kobayakawa, Hiroshi Endo, and Shuji Yoshizawa,
in Yoshimoto T. et al. (Ed.): Recent Advances in Biomagnetism (Proceedings of BIOMAG98),
pp. 474-477, Tohoku University Press, Sendai, Japan, 1999
"Robocode Bible - Road to Mightiest Robots" (book),
Michiaki Tatsubori, Ryo Sugihara, Ken Masumitsu, Yasumasa Kajinaga, and Teruo Koyanagi,
Gijutsu-hyoron-sha, May, 2003. (in Japanese)

Miscellaneous

Contact

  • email: contact info

  • mail address:
    UCSD/CSE - EBU3b 3226
    9500 Gilman Drive, Mail Code 0404
    University of California, San Diego
    La Jolla, CA 92093-0404 USA
  • tel: 858-534-9557 (direct)
  • twitter: id:sugiryo (half in Japanese, half in English)