Toshiyuki Asahi

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Treemaps, a visualization method for large hierarchical data spaces, are used to augment the capabilities of the Analytic Hierarchy Process (AHP) for decision-making. Two direct manipulation tools, presented metaphorically as a “pump” and a “hook,” were developed and applied to the treemap to support AHP sensitivity analysis. Users can change the importance(More)
The Analytic Hierarchy Process (AHP), a decision-making method based upon division of problem spaces into hierarchies, is visualized through the use of treemaps, which pack large amounts of hierarchical information into small screen spaces. Two direct manipulation tools, presented metaphorically as a “pump” and a “hook,” were developed and applied to the(More)
In this paper, we propose methods for testing the usability of graphical user interface (GUI) applications based on log files of user interactions. Log analysis by existing methods is not efficient because evaluators analyze a single log file or log files of the same user and then manually compare results. The methods proposed here solve this problem; the(More)
We studied the extent to which time-on-task is correlated with perception of usability for people who are familiar with a phone model and for those who are not. Our controlled experiment, conducted in Japan, correlated subjective usability assessments with time-on-task for expert and novice users on three different mobile phone models. We found that the(More)
We propose a new technology called the camera-typing interface, which can read printed characters such as URLs with a low-resolution camera. It realizes a type of ubiquitous information service using smart phones with cameras. This method includes two main advantages: automatic concatenation of sequential shots and automatic error correction by re-shooting.(More)
Ubiquitous Information Interfaces By Keiji YAMADA,* Shuji SENDA,† Toshiyuki ASAHI,† Toshihiko HIROAKI,† Hiroaki HATTORI* and Akitoshi OKUMURA* This paper describes ubiquitous information interface, which consists of an input function, an output function, and an interactive function. These functions have to be designed under the criteria such as real time,(More)