Morihiko Tamai

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In this paper, we propose a simulator for facilitating reliable and inexpensive development of ubiquitous applications where each application software controls a lot of information appliances based on the state of external environment, user’s contexts and preferences. The proposed simulator realistically reproduces behavior of application software on(More)
The Tele-immersive Dance Environment (TED) is a geographically distributed, real-time 3-D virtual room where multiple participants interact independent of physical distance. TED, a highly interactive collaborative environment, offers digital options with multiple viewpoints, enhancing the creative movement composition involved with dance choreography. A(More)
We propose an energy-aware video streaming system for portable computing devices, in which the video can be played back for the specified duration within the remaining battery amount. To save power, we introduce techniques (i) to reduce playback quality of a video at an intermediate proxy and (ii) to shorten working time of the network I/F card using(More)
Since participatory sensing relies on users' active participation, several monetary incentive mechanisms for attracting users' participation have been proposed. However, to make users participate in “heavy” sensing tasks (either physically or mentally), stronger incentive is required. Thus, the total amount of rewards paid by the client will(More)
To realize smart homes with sophisticated services including energy-saving context-aware appliance control in homes and elderly monitoring systems, automatic recognition of human activities in homes is essential. Several daily activity recognition methods have been proposed so far, but most of them still have issues to be solved such as high deployment cost(More)
The 3D tele-immersive (3DTI) environments are emerging as the next generation technique for tele-communication. In this paper, we present a novel and generic interface for view control in 3D environments. The interface uses Wii Remote, a wireless controller for a video game console. It allows the user to manipulate the virtual camera and 3D objects(More)
In this paper, we propose a method to deliver video for multiple wireless mobile users with different quality requirements. In the proposed method, we assume several proxies and wireless access points in the network. There are overlay links between these nodes, and certain amounts of bandwidths are reserved in advance. Each proxy is capable of executing(More)
Disaster area map generation and sharing are critical to disaster response operations. In post-disaster contexts however, cloud-based mapping services and data may be unavailable because of network challenges. Disruption Tolerant Network (DTN) architectures have been proposed for data sharing in challenged networks. However, map generation may be too(More)
In this paper, we propose SakuraSensor, a participatory sensing system which automatically extracts scenic routes information from videos recorded by car-mounted smart-phones and shares the information among users in quasirealtime. As scenic routes information, we target flowering cherries along roads since the best period of flowering cherries is rather(More)
In this paper, we propose a new video delivery method called MTcast (Multiple Transcode based video multicast) which achieves efficient simultaneous video delivery to multiple users with different quality requirements by relying on user nodes to transcode and forward video to other user nodes. In MTcast, each user specifies a quality requirement for a video(More)