Chance is an important element of a play. However, it has not been ensured in computer entertainment. The computer is a black box. Hence, players may suspect that it cheats (i.e., controls the result pretending it is purely random). Meanwhile, physical devices (e.g., dice) are fair. However, they may not excite the player as much. Many computer games use visual and auditory effects to make the player excited. Therefore, we propose the combination of physical randomness and digital effects. Accordingly, we made a prototype system called the AR dice tower, and confirmed its effectiveness by test play.

Although digital books are becoming increasingly popular, digital typography technologies are yet in their infancy. For example, many current digital books follow the patterns of conventional paper books, where the content is displayed in pages and the users have to turn a page using buttons or touch operations. The look and feel is similar to paper books, which is a significant factor that has promoted the acceptance of digital books. However, from the viewpoint of content representation, this familiar pattern does not fully exploit the merits and potentialities of digital content. To address this, we propose a digital book reader based on leading text that aims to mitigate interruption of reader concentration experienced in conventional methods. Moreover, we investigate the readability of the proposed method through quantitative evaluations.

Most of traditional retrieval keys are the place (folder), name and content of desired files. If a user does not remember these keys, it is difficult for him or her to access desired files. In order to solve this problem, we propose a file retrieval system that is based on provenance. In this paper, provenance means the history of the file's moving and editing that a user has experienced. By recording how and from where a user gets the file, the system enables the user to query, for example, "which files did I get from my teacher yesterday?", "which files did I download from the web page of my college last month?", and "which files did I edit by MS Word last week?" We present a model of provenance and describe how to use provenance as the keys of retrieval and how the system is constructed.

We implemented blow displays, which provide force feelings with no contact. Although blow displays can use only wind velocities and directions to represent information, they are less intrusive and less visually polluting to other media than other displays. We propose collaborative ambient systems to utilize blow displays' characteristics of spatiality and compatibility with other media. In collaborative ambient systems, blow displays direct the user to displays that provide rich information. Blow displays can also express information auxiliary to the main content the user is attending to. In this paper, we describe some ongoing applications and discuss their benefits and issues.

A search engine that can handle TV programs and Web content in an integrated way is proposed. Conventional search engines have been able to handle Web content and/or data stored in a PC desktop as target information. In the future, however, the target information is expected to be stored in various places such as in hard-disk (HD)/DVD recorders, digital cameras, mobile devices, and even in real space as ubiquitous content, and a search engine that can search across such heterogeneous resources will become essential. Therefore, as a first step towards developing such next-generation search engine, a prototype search system for Web and TV programs is developed that performs integrated search of those content, and that allows chain search where related content can be accessed from each search result. The integrated search is achieved by generating integrated indices for Web and TV content based on vector space model and by computing similarity between the query and all the content described by the indices. The chain search of related content is done by computing similarity between the selected result and all other content based on the integrated indices. Also, the zoom-based display of the search results enables to control media transition and level of details of the contents to acquire information efficiently. In this paper, testing of a prototype of the integrated search engine validated the approach taken by the proposed method.

Although various visualizationtechniques have been proposed for information retrieval tasks, most of them are based on a single strategy for viewing and navigating through the information space, and vague knowledge such as a fragment of the name of the object is not effective for the search.In contrast, people usually look for things using various vague clues simultaneously.For example, in a library, people can not only walk through the shelves to find a book they have in mind, but also they can be reminded of the author's name by viewing the books on the shelf and check the index cards to get more information.To enable such realistic search strategies, we developed a multiple-view information rerneval system where data visualization, keyword search, and category search are integrated with the same smooth zooming interface, and any vague knowledge about the data can be utilized to narrow the search space.Users can navigate through the information space at will, by modifying the search area in each view.