Kwang-Hee Han

Red for Romance, Blue for Memory

Decades of psychological research have shown that the color could affect human’s emotion and perception. However, the influence of this effect on human performance is still unknown. This study was performed to investigate and reveal the effect of the color red, blue and gray on memory through a word recognition task. When the presented video clip featured a red background, the model’s attractiveness was rated statistically higher than the other condition. The blue condition video viewers and their resulting performance on the word recognition task were better than the performances of the other color condition groups. This research implicates that a specific color has an effect on human perception and memory.

Effect of Target Size and Duration of Visual Feedback on Touch Screen

This study investigated performance and touching experience as a function of duration of visual feedback and target size on a touch screen. Five duration of visual feedback by three target size within-subject experiment was conducted. Relationship between performance and duration of visual feedback has an inverted-U shape trend. Performance and touching experience evaluation was worse with small targets. There was significant interaction between target size and duration of visual feedback. At the small target size condition performance was different from the other sizes. People could pay more attention to visual feedback because small size target condition was difficult. Another possible explanation is that the presented visual feedback size was very similar to small target condition. Longer lasting visual feedback might over complicate things for people and lead to confusion with the target.

Making Pixel Patterns Automatically for Camouflage – Using Color Information from Their Background

Camouflage is an attempt to obscure a target’s outline and match its background for hiding the target. Detectability of a target depends on the features of the background and changes in the surrounding. Thus, we have to consider visual information from the background and apply them to the development of an effective camouflage pattern. As dynamic environments are essential for designing an adaptive pattern, controlling digital images and making patterns automatically by use of computer can be efficient alternatives through the designing process of development and evaluation. In this study, we made the automatic pixel patterns program for the camouflage assessment. For making patterns, color information derived from background was used and pixel-dot type of pattern was considered in view of the digital pattern. Automatic stimuli-pattern maker developed in this study follows several steps; load an image, select an area, extract colors, and create a pattern. This automatic implementation has some benefits for design processes for camouflage pattern development. Further studies are needed not only for program-upgrade but also for improvement of color strategy through analyzing camouflage features.

Dashboard Design Factors on Emotional Change: How Separation between Center-Fascia and Center-Console, Button Orientation and Button Arrangement Influence Emotion

This study aims to find out which kind of car interior design factors influence human emotion change. A special focus was given on emotional effects of dashboard design. The selected design factors of dashboard, which are commonly observed in luxury cars, were the separation between center-fascia and center-console, the orientation of each button and the arrangement of buttons. Perceived luxuriousness and preference were measured out of seven points via an online questionnaire. It was hypothesized that i) when center-fascia and center-console are divided than when they are integrated, ii) when button orientation is horizontal than when it is vertical, iii) when buttons are arranged horizontally than when they are arranged vertically, perceived luxuriousness and preference would be increased. 2 x 2 x 2 repeated-measures ANOVA was conducted on perceived luxuriousness and preference with division, orientation and arrangement as factors. Results showed that when button orientation is horizontal, perceived luxuriousness and preference were higher. Perceived luxuriousness and preference were also higher when buttons are arranged horizontally. An interaction effect between button orientation and arrangement on preference was found. This implies that higher preference can be triggered when at least one factor is horizontal. No other significant effects were found.This study was conducted to make a car interior design guideline which associates particular design factors that trigger particular emotional response. Future studies should investigate low-level psychological elements and conduct factor analysis of various emotional adjectives.

Unique Motivation for Using Global Social Network Site in Korea

This study is an attempt to connect the distinctive motivation of Korean self-expression [1] with growth of the global social network sites (SNSs) in Korea. To explore the motivation using global SNSs, we conducted in-depth interview. The result of the interviews suggests that Korean expected to look more attractive or charming when they have foreign online friends, thus leading them to seek to make such foreign friends on Facebook, a widely used SNS. In addition, a questionnaire was conducted to analyze the correlation between the offline and online tendencies of Koreans to prefer foreign friends. The results showed that the respondents perceived themselves as more attractive if he (she) had a foreign friend offline and as more attractive if he (she) was a person who had comments from foreign friends on Facebook. The above results implicate that there are various motives for using global SNSs, depending on the cultural backgrounds of the users.

Color Image Effect of Online Community on Age: Focusing on Self-expression

Online social network service prevents older adults from isolating. It can be the tool of self-expression in the social context as well as the mean of sharing information. Affiliated community itself can be a self-expressive symbol of the member sometimes. How the member feel the community can affect sense of belonging. This study investigated age difference on perceived self-expression depending on color image of online community webpage. The results indicated that two different age groups showed different perceived patterns to ‘soft-hard’ and ‘warm-cool’ image dimensions. This suggests that interface designers consider that color image of interfaces can provide different expression among different age groups.

Camouflage Assessment of Color Pattern Strategies in Different Environmental Contexts

This study examined the effectiveness of adaptive camouflage patterns according to environmental contexts. We performed visual search tasks using photo simulation to evaluate the effectiveness of camouflage strategies. Pattern combination strategies from a previous study were used. Each one of the 4 strategies (Average [A], AverageRandom [AR], Main [M], and MainRandom [MR]) were presented in 3 environmental contexts (Woodland, Rural, and Urban), and performance (Error Rate) was measured. An analysis of performance revealed the main effect of strategy and a significant interaction between strategy and the context. Strategy A appeared to be more effective than the others. The A and AR strategies were better in the Woodland context, and strategies A and M appeared to be superior to the others in the Urban and Rural contexts. This study can be the foundation for determining optimal adaptive camouflage patterns in different environmental contexts and provide a theoretical basis for future military uniforms.

Can Color Tell? Smartphone LED Notification Color and Users’ Perception of the Situation

In this study, we investigated whether the use of LED colors that are cognitively congruent with the notification situations can help smartphone users to intuitively understand the situation. We examined whether cognitive loads placed on smartphone users differ between when single color is used and when RGB colors are jointly used to better match the situations. We predicted that participants will more quickly and correctly understand the situations when RGB colors are used than when single color is used because the use of RGB colors will improve their memory (i.e., the process of encoding and retrieval) due to the high cognitive congruency between LED colors and situations. In an experiment, we randomly assigned participants to single-color LED notification groups (i.e., red color group and white color group) and RGB color notification group and measured their cognitive loads by assessing their task performance (e.g., response time and error rate) and subjective ratings. We found no overall difference in participants’ cognitive loads between groups. However, in an additional analysis, we found a significant difference exists in early rounds of experiment although the difference disappeared as participants accumulate more rounds of experiences. Our results suggest that the use of proper LED colors can help smartphone users to more effectively and efficiently understand the situations; however, the positive effect will be low for those who have more experiences of LED notification lights. We believe our study provides important implications to the study on the design of LED notification lights.

Multitasking and Performance under Time Pressure

This study is intended as an investigation of relationship between task-switching and time pressure. Task-switching means switching attention from one task to another task. There are two sub-categories: task-switching which is involuntary task-switching, switching task caused by external stimulus, and voluntary task-switching, switching task caused by internal motivation. To investigate whether time pressure makes people do task-switching more frequently and perform task better or not, an experiment was executed. The existence of stopwatch was set as independent variable. The number of task-switching and result of task performance were set as dependent variables. After the experiment, a survey was taken by participants to examine their evaluation on experiment, time pressure, and preference of task-switching. As a result, task-switching occurred more frequently in timer condition when participants were not interested in tasks. Moreover, participants performed tasks better in timer condition when the difficulty level of task was high. These results lead to the conclusion that effect of time pressure varies according to interest in tasks and level of difficulty.

The Effect of Presentation on Visual Working Memory

This paper reports experiments investigating the effect of presentation on visual working memory (VWM) when set-size increases. The capacity of VWM is limited to approximately four items (Luck & Vogel, 1997) and increasing set-size impairs the performance in visual tasks. Also, the performance in visuospatial tasks was better in the simultaneous presentation than in the sequential presentation. However, it is possible that large set-size in the simultaneous presentation caused overload in visual processing, and also, there is a possibility to increase interference among stimuli.Therefore, we speculated that performance in a simultaneous presentation would show a sharper decrease than in a partitioned presentation, which divides stimuli into two halves in order to reduce visual processing load and interference among stimuli when number of stimuli increases. Thus, the experiments with two types of set-size and two types of presentations (simultaneous and partitioned) were performed.The experiment examined whether a probe item was old or novel after seeing 4 or 8 items that appeared at random locations. These items were displayed either in simultaneous or in a partitioned manner. The results revealed a significant interaction between set-size and presentation. In a small set-size condition, performance was better in the simultaneous presentation than in the partitioned presentation. However, no difference was found between performances for both presentations in the large set-size condition, as it was influenced by the partitioned presentation. The results proposed that the partitioned presentation was more stable method to show items than the simultaneous presentation when set-size is large.