Articles by Young Sam Ryu
Young Sam Ryu
is an Assistant Professor of Ingram
School of Engineering at Texas
State University-San Marcos. His
research area includes human
computer interaction, usability
engineering, and safety. He
received his Ph.D. (2005) from the
Grado Department of Industrial
and Systems Engineering at
Virginia Tech.
Usability Evaluation of Touch-less Mouse, Based on Infrared Proximity Sensing
Abstract In this work, we examined a touchless mouse, which is a Human-Machine Interface (HMI) device for non-contact gesture inputs to a computer system. The touchless or T-less mouse is used by moving a finger without touching any device or surface. We evaluated it according to the guidelines and testing procedures for evaluating computer pointing […] [(English) Read More]
Usability Evaluation of Randomized Keypad
Abstract In this work, the usability of a randomized numeric keypad was examined and compared to the usability of a conventional numeric keypad. The comparison used completion time measurements and the error rate of short (4 digit) and long (8-digit) PINs to contrast efficiency and accuracy of the keypads. The results showed that the average […] [(English) Read More]
Insights for the TV Interface from the Mobile Phone Interface
Abstract We reviewed the service structure, needs analysis, user interface model, and interaction analysis for television (TV) and mobile phones. Due to the increasing use of services such as electronic program guide (EPG), digital video recorder (DVR), and pay-per-view (PPV), we concluded that text input for the TV interface will be inevitable. Furthermore, jumping interaction […] [(English) Read More]
Decision Models for Comparative Usability Evaluation of Mobile Phones Using the Mobile Phone Usability Questionnaire (MPUQ)
Abstract A comparative usability evaluation was performed using various subjective evaluation methods, including Mobile Phone Usability Questionnaire (MPUQ). Further, decision-making models using Analytic Hierarchy Process (AHP) and multiple linear regression were developed and applied. Although the mean rankings of the four phones were not significantly different across the evaluation methods, there were variations across the […] [(English) Read More]
Reliability and Validity of the Mobile Phone Usability Questionnaire (MPUQ)
Abstract This study was a follow-up to determine the psychometric quality of the usability questionnaire items derived from a previous study (Ryu and Smith-Jackson, 2005), and to find a subset of items that represents a higher measure of reliability and validity. To evaluate the items, the questionnaire was administered to a representative sample involving approximately […] [(English) Read More]