Morihiko Tamai

About Me

I am currently a postdoctoral fellow at the Graduate School of Information Science, Nara Institute of Science and Technology (NAIST). I am a member of the Foundations of Software Lab (a.k.a. ito-lab). Email:

Research

Research Interests

• Energy-aware video streaming for portable computing devices
• Resource-aware service composition for video multicast to heterogeneous mobile users
• Market-based resource allocation in PC grid environments
• Simulator for testing smartspace applications

My main research focus is on design and implementation of multimedia communication systems including portable computing devices on wireless environments. In particular, I am interested in energy-aware video streaming system for portable wireless devices, and how to construct resource efficient service overlay for video multicast to these devices over content delivery networks. I am also interested in Grid computing and ubiquitous computing systems. I am involving in UbiREAL project, and developing the network simulator of UbiREAL and a rule-based device control application using UPnP protocols.

Publications

International Conference

• Morihiko Tamai, Wanmin Wu, Klara Nahrstedt, and Keiichi Yasumoto: ``A View Control Interface for 3D Tele-immersive Environments,'' to appear in the Proc. of the 2008 IEEE Int'l Conf. on Multimedia and Expo (ICME'08), 2008.
• Morihiko Tamai, Keiichi Yasumoto, Naoki Shibata, Minoru Ito, and Klara Nahrstedt: ``Transcasting: Cost-Efficient Video Multicast for Heterogeneous Mobile Terminals,'' to appear in the Proc. of the 16th Int'l Workshop on Quality of Service (IWQoS'08), 2008. (PDF)
• Kazuya Uyama, Morihiko Tamai, Yoshihiro Murata, Naoki Shibata, Keiichi Yasumoto, and Minoru Ito: ``A Delivery Method for Compound Video Playback in Wireless Network,'' Proc. of the 2006 Int'l Workshop on Parallel and Distributed Multimedia Computing (ParDMCom'06), LNCS4331, pp. 803-812, 2006. (PDF)
• Hiroshi Nishikawa, Shinya Yamamoto, Morihiko Tamai, Kouji Nishigaki, Tomoya Kitani, Naoki Shibata, Keiichi Yasumoto, and Minoru Ito: ``UbiREAL: Realistic Smartspace Simulator for Systematic Testing,'' Proc. of the 8th Int'l Conf. on Ubiquitous Computing (UbiComp'06), LNCS4206, pp. 459-476, 2006. (PDF)
• Morihiko Tamai, Naoki Shibata, Keiichi Yasumoto, and Minoru Ito: ``Network Simulation Architecture for Smartspace,'' Proc. of the 2006 System Support for Ubiquitous Computing Workshop (UbiSys'06), Online proceedings (Poster paper), 2006. (PDF)
• Morihiko Tamai, Naoki Shibata, Keiichi Yasumoto, and Minoru Ito: ``An Energy-Aware Video Streaming System for Portable Computing Devices,'' Proc. of the 7th IEEE Int'l Conf. on Mobile Data Management (MDM'06), CD-ROM proceedings (Demo paper), 2006. (PDF)
• Tao Sun, Morihiko Tamai, Keiichi Yasumoto, Naoki Shibata, Minoru Ito, and Masaaki Mori: ``MTcast: Robust and Efficient P2P-based Video Delivery for Heterogeneous Users,'' Proc. of the 9th Int'l Conf. on Principles of Distributed Systems (OPODIS'05), LNCS3974, pp. 176-190, 2005. (PDF)
• Shuichi Yamaoka, Tao Sun, Morihiko Tamai, Keiichi Yasumoto, Naoki Shibata, and Minoru Ito: ``Resource-Aware Service Composition for Video Multicast to Heterogeneous Mobile Users,'' Proc. of the 1st ACM Int'l Workshop on Multimedia Service Composition (MSC'05) (ACM Multimedia 2005 Workshop), pp. 37-46, 2005. (PDF)
• Morihiko Tamai, Naoki Shibata, Keiichi Yasumoto, and Minoru Ito: ``Distributed Market Broker Architecture for Resource Aggregation in Grid Computing Environments,'' Proc. of the 5th IEEE Int'l Symposium on Cluster Computing and the Grid (CCGrid'05), CD-ROM proceedings, 2005. (PDF)
• Morihiko Tamai, Tao Sun, Keiichi Yasumoto, Naoki Shibata, and Minoru Ito: ``Energy-aware Video Streaming with QoS Control for Portable Computing Devices,'' Proc. of the 14th ACM Int'l Workshop on Network and Operating Systems Support for Digital Audio and Video (NOSSDAV'04), pp. 68-73, 2004. (PDF)
• Morihiko Tamai, Tao Sun, Keiichi Yasumoto, Naoki Shibata, and Minoru Ito: ``Energy-aware QoS Adaptation for Streaming Video based on MPEG-7,'' Proc. of the 2004 IEEE Int'l Conf. on Multimedia and Expo (ICME'04), CD-ROM proceedings (Poster paper), 2004. (PDF)
• Morihiko Tamai, Keiichi Yasumoto, Naoki Shibata, and Minoru Ito: ``Low Power Video Streaming for PDAs,'' Proc. of the 8th Int'l Workshop on Mobile Multimedia Communications (MoMuC'03), pp. 31-37, 2003. (PDF)

Software

• ezxdisp - yet another simple graphics library

Misc

Prime Numbers

I am interested in prime numbers. I found a 153188 digit prime number 19911001*2^508852+1 in March, 2005. It was the 265th largest known prime when it was found. I am continuously looking for the prime numbers of the form 19911001*2^n+1 (October 1, 1991 is the foundation date of NAIST).

All of the primes that I found: here