International Journal of Human-Computer Interaction

Ko, Sang Min; Chang, Won Suk; Ji, Yong Gu

doi: 10.1080/10447318.2012.722466pmid: N/A

Through the rapid spread of smartphones, users have access to many types of applications similar to those on desktop computer systems. Smartphone applications using augmented reality (AR) technology make use of users' location information. As AR applications will require new evaluation methods, improved usability and user convenience should be developed. The purpose of the current study is to develop usability principles for the development and evaluation of smartphone applications using AR technology. We develop usability principles for smartphone AR applications by analyzing existing research about heuristic evaluation methods, design principles for AR systems, guidelines for handheld mobile device interfaces, and usability principles for the tangible user interface. We conducted a heuristic evaluation for three popularly used smartphone AR applications to identify usability problems. We suggested new design guidelines to solve the identified problems. Then, we developed an improved AR application prototype of an Android-based smartphone, which later was conducted a usability testing to validate the effects of usability principles.

Samanta, Debasis; Sarcar, Sayan; Ghosh, Soumalya

doi: 10.1080/10447318.2012.728483pmid: N/A

Of late there has been significant development in Information and Communication Technology (ICT), which offers interaction with computing systems in a large scale. Text input mechanisms in users’ own languages are necessary for bringing the ICT advantages to the English illiterates. QWERTY keyboard, however, which was designed for text entry in English, is not as suitable for text composition in other languages. As an alternative, researchers advocate virtual keyboards in users’ mother languages. This article proposes an approach to designing virtual keyboards suitable for text entry in Indian languages. Composition of texts in Indian languages using virtual keyboards needs special attention due to the presence of large character sets, complex characters, inflexions, and so on. First, we examine the suitability of existing design principles in developing virtual keyboards in Indian languages. Then we propose a virtual keyboard layout suitable for efficient text entry in Indian languages. We have tested our approach with the three most spoken languages in India, namely, Bengali, Hindi, and Telugu. Performance of the keyboards have been evaluated, and the evaluation substantiates that proposed design achieves on average higher text entry rather than with conventional virtual keyboards. The proposed approach, in fact, provides a solution to deal with complexity in Indian languages and can be extended to many other languages in the world.

Romano Bergstrom, Jennifer C.; Olmsted-Hawala, Erica L.; Jans, Matt E.

doi: 10.1080/10447318.2012.728493pmid: N/A

Cognitive decline is inherent with age. Despite known cognitive limitations, older adults are generally not taken into account during website design. Understanding age-related differences in website navigation is instructive for website design, especially considering the growing number of older adults who use the Internet. This article presents usability and eye-tracking data from five independent website usability studies that included younger and older participants. Overall results revealed age-dependent differences in eye movement and performance during website navigation on some of the sites. In particular, older participants had lower accuracy in one study and took longer to complete tasks in two studies compared to younger participants, they looked at the central part of the screen more frequently than younger participants in two studies, and they looked at the peripheral left part of the screen less frequently and took longer to first look at the peripheral top part of the screen than younger participants in one study. These data highlight the potential for age-related differences in performance while navigating websites and provide motivation for further exploration. Implications for website design and for usability practitioners are discussed.

Celozzi, Cesare; Lamberti, Fabrizio; Paravati, Gianluca; Sanna, Andrea

doi: 10.1080/10447318.2012.729455pmid: N/A

Existing tracking methods designed for interacting with projection-based displays generally require visible artifacts to be introduced in the environment in order to guarantee effective stability and accuracy. For instance, in optical-oriented approaches, either the camera sensor or the reference pattern used for tracking are often located within the user's sight (or interfere with it), thus occluding portions of the scene or altering the perception of the virtual environment. Several ways to tackle these issues have been recently explored. Proposed approaches basically aim at making the presence of tracking references in the virtual space transparent to the user. However, such solutions introduce possibly critical constraints on required hardware or environment configuration. In this work, a novel tracking approach based on imperceptible fiducial markers is proposed. The approach relies on a hiding technique that allows digital images to be embedded in (and retrieved from) a projected scene by exploiting the properties of light polarization and additive color mixing. In particular, the virtual scene is obtained by overlapping the light beams of two projectors and by dealing with markers’ hiding via color compensation. A prototype setup has been deployed, where interaction with a flat surface projection environment has been evaluated in terms of tracking accuracy and artifacts avoidance performance by using a consumer camera equipped with a polarizing filter. Although the performed tests presented in this article represent only a preliminary and a partial evaluation of the proposed approach, they provided encouraging results indicating that the proposed technique could be possibly applied in more complex interaction scenarios still with limited hardware requirements.