Learn More
In many metropolitan areas, passengers of public transportations move between home and their destinations such as offices, schools, and entertainment places. Often, they use storing shelves/areas to temporarily place their personal belongings and they may leave them behind. We have developed CRUISE/r which is a prototype of lost and found systems utilizing(More)
In this paper, we present hierarchy-based any-cast routing (HAR), a routing protocol for collecting data over multihop, wireless sensor networks. The design of the protocol aims to satisfy the requirements of sensor networks that every sensor transmits sensed data to the base station periodically or spontaneously. The base station constructs hierarchical(More)
Information sharing has undeniably become ubiquitous in the Internet age. The global village created on the Internet provides people with instant access to information and news on events occurring in a remote area, including access to video content on websites such as YouTube. Thus, the Internet has helped us overcome barriers to information. However, we(More)
The proliferation of networked mobile devices that can capture and communicate various kinds of data provides an opportunity to design novel man-machine sensing environments of which this paper considers participatory sensing. To achieve energy efficiency and reduce data redundancy, we propose Aquiba protocol that exploits opportunistic collaboration of(More)
Recent mobile devices are integrated with various kinds of sensors, thereby allowing people to capture what stationary sensing devices cannot easily acquire. We term the systems that exploit the ubiquity of the users of such devices <i>Human Probes</i>. To realize a Human-Probe environment, our research group has examined the usefulness of pressure sensors(More)
Capturing useful data in a complex and dense urban space is an inherently challenging task. There is so much data people can capture in a city, yet they may fail to capture important information, some of which they don't even know that it exists. In this paper, we discuss an implicit approach to urban sensing and introduce an implicit sensing system that(More)
Temperature in an urban area exhibits a complicated pattern due to complexity of infrastructure. Despite geographical proximity, structures of a group of buildings and streets affect changes in temperature. To investigate the pattern of fine-grained distribution of temperature, we installed a densely distributed sensor network called UScan. In this paper,(More)
An increasing popularity of smartphones affects interaction behaviors between people. The ubiquity of smartphones with embedded sensors can enable attractive sensing applications for collecting and reporting data in participatory sensing environment. However, time and monetary cost hinder people from providing sensing data using their smartphones.(More)