Pilsung Choe

Exploring factors influencing multitasking interaction with multiple smart devices

The intention of this study is to investigate multitasking interaction with multiple smart devices and to unveil factors that play important roles in multitasking scenarios. A survey was carried out and 240 respondents participated whose scores ultimately demonstrated the degree of influence of various items on multitasking interaction with multiple smart devices. Then an exploratory factor analysis was conducted and a seven-factor model named MINDCOS was derived, including Motivation, Input, Navigation and control, Display screen, Cognitive workload, Output, Spatial distribution. The model was utilized to describe the scenario of multitasking interaction with multiple smart devices and the top three factors which illustrated the total variance the most were used to analyze related applications. Then the relationship between the factors and perceived behavior intention of multitasking interaction was tested by regression analysis. This study also found whether users had multitasking experience had a significant impact on their perceived influence of two factors which are Navigation and control and Output.

Influence of Different Types of Vibrations on Technical Acceptance of a Mobile Game Aiming for Hedonic Satisfaction

Rapid increases in the smartphone gaming industry have made in-game usability increasingly important. However, industrial usability is still focused on performance although high performance is not necessarily a goal in actual games. Mobile gamers largely want to increase their hedonic satisfaction. So already established usability guidelines can fail in mobile gaming. Focusing on vibrations as a haptic feedback, this study analyzed the influences of intensity and length of vibrations on user perceptions based on the technology acceptance model aiming for hedonic satisfaction when mobile gaming. A smartphone game was modified to generate seven types of vibrations for a human factors experiment with 70 subjects and administered a questionnaire to measure their perceptions of the game influenced by the vibrations. The results show that including vibrations significantly increases the perceived ease of use, perceived usefulness, and cognitive concentration in the game. The stronger vibration intensity significantly improves user perceptions of the usefulness and cognitive concentration, whereas the length of vibration is not a critical factor as long as vibrations exist.

Providing customisation guidelines of mobile phones for manufacturers

Customisation of mobile phones is a process of producing products according to individual needs on design, cost, and easiness of the phones. With the aim of identifying the most important features in customising mobile phones, 288 questionnaires were collected and analysed. The result showed that ‘text message’, ‘battery’, ‘contacts’, ‘software updates’, and ‘display size’ were highly required to customise. Among six factors (physical design, technical design, cost of entertainment, cost of information, cost of durability, easiness of use) obtained from a factor analysis, the most important reason for users to customise mobile phones was that they wanted to use a mobile phone easily. Cost of durability and cost of information were also important motivations for customisation of mobile phones. Finally, this research showed that gender and user experience were significant factors for customisation.

Leap-Motion Based Online Interactive System for Hand Rehabilitation

Insufficient recognition to hand afunction caused by overwork, injury and geratic complications leads to inadequate auxiliary for hand rehabilitation. Patients’ rehabilitative training is usually limited to rehabilitation center in hospitals, leaving their time at home inefficient for precise recovery.

The Hedonic Effects of Smartphone Vibrations in Mobile Gaming for Male Users

Objective: This study investigates the influences of vibrations on hedonic satisfaction based on four kinds of perceptions (perceived ease of use, perceived usefulness, perceived enjoyment, cognitive concentration) when mobile gaming. Background: As mobile gaming is becoming more and more popular for smartphone users, they might want to have more hedonic satisfaction instead of focusing on traditional usability criteria such as efficiency, effectiveness, and satisfaction. Method: We conducted a human-factors experiment with 35 male subjects to evaluate hedonic satisfaction in the mobile game configured by 7 vibration types having different levels of intensity and length. Results: The results revealed that the use of vibration significantly increases the perceived ease of use, perceived usefulness, and cognitive concentration. In addition, the intensity of vibration makes differences of perceived usefulness and cognitive concentration. Conclusion: Vibration can be effectively used to improve hedonic satisfaction of smartphone users in mobile gaming when they are not allowed to turn the sound effects on. Application: This study helps game designers effectively provide vibration feedback of mobile games for smartphone users.

Driving Safety Considered User Interface of a Smartphone: An Experimental Comparison

With the rapid advancement of mobile technology, information searches by drivers using smartphones have increased despite the potential risk of accidents. The small screen size of smartphones greatly distracts driving performance. Apart from traffic regulations that prohibit smartphone usage while driving, a better user interface design of smartphones for drivers is also a critical issue in regard to increasing driving safety and user satisfaction.

RFID-Based Road Guiding Cane System for the Visually Impaired

The RFID-based road guiding cane is a navigation system especially designed for the visually impaired. Geographic location, traffic light signals, and business information are saved in a series of RFID labels constructed beneath the sidewalk. With the road guiding cane reading the RFID labels, the visually impaired can locate themselves, be aware of traffic light signals, and find business information near them on the road. After users set the destination, the cane automatically directs the routes for users via voice by specifying the current location and keeping track of previous locations. Compared with the Global Positioning System, the RFID-based road guiding cane system is more reliable, more accurate, cost-saving, and versatile in providing precise location-based services for the visually impaired.

Improving the User Interface for Reading News Articles through Smartphones in Persian Language

Space limitation in small devices such as smartphones which are able to access the Internet is an important issue in regard to increasing usage of these devices. Moreover, a browser is a one of tools for transition of a website which is designed for a big screen like the display of a desktop computer. This paper experimentally evaluated user-interface alternatives based on three tasks (finding, re-finding, reading, and browsing) and two display orientations (horizontal, vertical). In addition, the survey results showed the methods (Pop out, Full screen, and Auto zooming) and the orientations affect actual usage.

Smartphone Information Displays When Reading News in Persian and English Languages

By their nature, smartphones must have small screens, and that is one of their limitations. Many users have trouble reading information on the Internet on such small screens because Internet browsers are usually designed for computers that have larger screens than smartphones. This study evaluates the usability of alternative user interfaces when reading news articles on smartphones. An experiment was conducted involving 120 smartphone users who were asked to evaluate six types of user interfaces based on three methods (pop-up, full-screen, and auto-zooming) and two display orientations (horizontal, vertical) in one of two languages (English and Persian). The participants were assigned four typical tasks that users must perform to obtain information from the Internet, that is, finding, refinding, reading, and browsing; they were asked to conduct the tasks in random order. In addition, a questionnaire was used to measure the efficiency and effectiveness of the participants’ completion of the tasks, as well as their satisfaction, compatibility, and enjoyment of the undertakings. The results indicated that method, orientation, and language affected the actual usage and the time used. Based on the human factor experiment, the full-screen method was preferred in refinding and reading, whereas the pop-up method was preferred in browsing and finding. In terms of orientation, the vertical mode was preferred, and each user’s performance in the vertical mode was better in all tasks except browsing. Of interest, using the English language turned out to be more satisfying, enjoyable, and efficient to the Persian users who did the experiment in English as their second language.

The Effect of Tactile Feedback on Mental Workload During the Interaction with a Smartphone

This empirical study examines the adequacy of tactile feedback to present status information about the progress of Internet-based services on mobile devices and possibilities to compensate age-related changes in users performance. Therefore the user experience of mobile browsing was compared using three different vibration signals and two different levels of process times. In this experiment the participants had to perform two tasks simultaneously. The participants experienced six different (combinations treatments) permutations in treatment with regard to ‘vibration type’ and ‘process time.’ The user experience was measured by the Technology Acceptance Model and the subjective mental workload by the NASA Task Load Index using a questionnaire. The experiment revealed that a short vibration signal at the end of a process is capable of increase the user experience. Therefore, ‘perceived enjoyment’ as well as ‘perceived usefulness’ improved. However, the characteristic factor ‘mental workload’ decreased with usage of tactile feedback.