Yoshinari Shirai

A history-centric approach for enhancing web browsing experiences

Browsing Web pages, which plays an important part of our daily creative knowledge work, often includes purposefully revisiting pages we have browsed before. Many of the existing tools and approaches for revisitation clearly distinguish the use of history from Web browsing. The approach presented in this paper blurs the distinction between browsing the Web and visiting stored pages in a personal Web browsing history database. The HCB (History-Centric Browsing) system allows a user to browse a previously visited Web page stored in the history database in the same way as browsing a page on the Web. The system associates pages from the database to the currently displayed page through three types of relevancies: temporal sequence, URL/location-based proximity, and content similarity. The HCB-stat, HCB-vis, and HCB-tempo components use the associations to enrich the current page-viewing experience.

t-Room: Next Generation Video Communication System

In this paper, we present t-Room, the next generation video communication system we are developing. Our approach is to build rooms with identical layouts, including walls of display panels on which users and physical or virtual objects are all shown at life-size. In this way, the user space enclosed by t-Rooms surrounding displays can be shared as a common space at any other site. In other words, the enclosed spaces overlap each other. This configuration effectively provides symmetric reproduction of the audio-visual information surrounding local and remote users and objects. The feeling provided by t-Room is different from that by conventional videoconferencing systems, since there is no spatial barrier separating users such as the video screen of a conventional videoconferencing system. Furthermore, t-Room benefits in every way from Next Generation Network (NGN) technology: QoS, service productivity, and security. We view t-Room as a future form of telephone service.

A new loudspeaker design for the enhancement of sound image localization on flat display panels

In most audio‐visual multimedia applications, conventional stereo loudspeakers have been used to implement auditory displays. However, a fundamental problem with this kind of displays is that only the listeners situated at the sweet spot and over the symmetrical axis of the loudspeaker array are able to accurately localize the sound images. Although a number of audio signal processing algorithms have been proposed to expand the listening area, relatively less study on new loudspeaker configurations has been explored. This paper introduces a simple, yet effective, loudspeaker design to enhance the localization of sound images over the surface of flat display panels. In contrast to previous approaches, expansion of the listening space is achieved by attachment of rigid barriers which physically modify the sound radiation pattern of the loudspeakers. Moreover, numerical simulations, experimental sound measurements, and subjective tests have been preformed to validate a prototype of the proposed loudspeaker d...