概念体系に基づく視点情報を用いた文書整理支援システムに関する研究

University of Tokyo (東京大学

IMPROVING RETRIEVAL EFFECTIVENESS BY INTEGRATED QUERYING OF IMAGES AND TEXT

An integrated retrieval system is developed, enabling simultaneous querying of the image and the text content of a document - a feature not supported by the existing retrieval systems. An integrated query is expressed using the natural language expressions. Image content is queried either based on the color-spatial properties or based on the induced sensations, derived from the color arrangements. The vagueness of the natural language expressions used to query the image content is modeled employing the fuzzy set theory. Integrated retrieval experiment, performed on a database of 1,022 Web pages containing images and text, shows that, when using the integrated queries, the number of retrieved documents in average reduces to 14% of the number obtained by the image or text queries. Image retrieval experiment, involving a database of 1,100 color images and evaluated using a questionnaire involving 10 subjects, shows 70% agreement between the system s and the user s ranking of images. It follows that the proposed integrated querying approach, compared to the conventional image and text querying approaches, enables a more effective retrieval, essential for the large-scale databases like the Internet

A Proposal for a BBS with Visual Presentation for Online Data Analysis

The concept of a bulletin board system (BBS) equipped with information visualization techniques is proposed for supporting online data analysis. Although group discussion is known to be effective for analyzing data from various viewpoints, the number of participants is limited by time and space constraints. To solve that problem, this paper proposes to augment a BBS, a popular web based tool. In order for discussion participants to share data online, the system provides them with a visual representation of target data, which elicits comments from participants as well as compares these comments. In order to illustrate the concept's potential, a BBS equipped with KeyGraph is also developed for supporting online chance discovery. It has functions for making visual annotations on the KeyGraph as well as a function for retrieving similar scenarios. The experimental results show the effectiveness of the BBS in terms of the usefulness of scenario generation support functions as well as that of scenario retrieval engines

VISUAL ANALYSIS OF DISCUSSION FLOW ON KEYGRAPH-BASED BBS

A method for visualizing discussion flow is proposed for analyzing the thread in KGBBS (KeyGraph-based BBS). It is known that group discussion is effective for chance discovery, in which information visualization plays an important role in providing participants with a material to that brainstorm various ideas, opinions, and interpretations. In order to enable online discussion while sharing the same visualized material, KGBBS is proposed based on KeyGraph, which is one of the typical visualization techniques in chance discovery. The aim of this paper is to utilize the result of discussion using KGBBS, by visualizing discussion flow of the thread in KGBBS. The method consists of 2 kinds of visualization techniques — a comment chain diagram to visualize the structure of comment chain, and a visual summary on KeyGraph to visualize concrete transition of topics through successive 2 or 3 comments. The proposed method is applied to actual discussion data, and the analysis results show the combination of both the visualization techniques, making it possible to analyze concrete transition of topics without reading comments in a thread.Discussion flow analysis, information visualization, online discussion, BBS, visual data analysis, chance discovery, KeyGraph