Quantifying the colour appearance of displays.

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Warm-Cool Emotions of LED Lightings around 5,000K

In this study, warm-cool feelings of near-white lightings were investigated after the subjects??? eyes being adapted to 5,000K. The psychophysical experiment was carried out in a dark room using 5 channels LED lighting booth. In the experiment, total of 48 test lightings around 5,000K were generated using the booth. Total of 20 subjects evaluated warm-cool feelings of each test lighting. The results showed that lower CCT tended to have ???Warm??? feeling, while higher CCT tended to arouse ???Cool??? feeling. When CIECAM02 H is in the range of 0-100 and 380-400, ???Warm??? feeling was strongly evoked and when H is in the range of 250-300, ???Cool??? feeling was strongly aroused. Also, when test lightings have same hue, the one having higher chroma aroused stronger feeling on either ???Warm??? or ???Cool???. Emotion model test results showed Koo???s model, which is based on lighting colors, showed better performance than the model developed based on color patches

Discomfort luminance level of head-mounted displays depending on the adapting luminance

The Images in an immersive head-mounted display (HMD) for virtual reality provide the sole source for visual adaptation. Thus, significant, near-instantaneous increases in luminance while viewing an HMD can result in visual discomfort. Therefore, the current study investigated the luminance change necessary to induce this discomfort. Based on the psychophysical experiment data collected from 10 subjects, a prediction model was derived using four complex images and one neutral image, with four to six levels of average scene luminance. Result showed that maximum area luminance has a significant correlation with the discomfort luminance level than average, median, or maximum pixel luminance. According to the prediction model, the discomfort luminance level of a head-mounted display was represented as a positive linear function in log(10) units using the previous adaptation luminance when luminance is calculated as maximum area luminance

Transparent effect on the gray scale perception of a transparent OLED display

Gray scale perception of transparent OLED displays was explored. The difference in luminance between transparent and non-transparent stimuli in the overall gray range was compared. The transparent effect appeared in gray scale perception. The range of the transparent effect was determined experimentally. To explore the practical application of this effect, we proposed a new tone-curve based on the transparent effect. In the preference experiment, participants indicated a higher preference score for the new tone-curve. This implied that the transparent effect is valid and applicable to real situations

Estimation of Perceptual Surface Property Using Deep Networks with Attention Models

How we perceive property of surfaces with distinct geometry and reflectance under various illumination conditions is not fully understood. One widely studied approach to understanding perceptual surface property is to derive statistics from images of surfaces with the goal of constructing models that can estimate surface property attributes. This work presents machine learning-based methods to estimate the lightness and glossiness of surfaces. Instead of deriving image statistics and building estimation models on top of them, we use deep networks to estimate the perceptual surface property directly from surface images. We adopt the attention models in our networks, to allow the networks to estimate the surface property based on features in certain parts of images. This approach can rule out image variations due to geometry, reflectance, and illumination when making the estimations. The networks are trained with perceptual lightness and glossiness data obtained from psychophysical experiments. The trained deep networks provide accurate estimations of surface property that correlate well with human perception. The network performances are compared with various image statistics derived for estimation of perceptual surface property

Flexible Technique to Enhance Color-image Quality for Color-deficient Observers

Color-normal observers (CNOs) and color-deficient observers (CDOs) have different preferences and emotions for color images. A color-image quality-enhancement algorithm for a CDO is developed to easily adjust images according to each observer`s preference or image quality factors. The color-perception differences between CDO and CNO are analyzed and modeled in terms of the YCbCr chroma ratio and hue difference; then the color-shift method is designed to control the degree of color difference

A Radically Assembled Design-Engineering Education Program with a Selection and Combination of Multiple Disciplines

A radically assembled design-engineering program in the school of Design and Human Engineering (DHE) at Ulsan National Institute of Science and Technology (UNIST), newly founded in 2009, is presented. The most distinctive feature in DHE is that all students are required to select two disciplines for their major among three major disciplines, which are; (i) Integrated Industrial Design, (ii) Affective and Human Factors Engineering, and (iii) Engineering and Systems Design. The DHE's major system of the new design-engineering program was developed to foster the next generation designers and engineers, having talent in not only creative ideation but also systematic realization. In this paper, we first describe the founding background, educational rationale and curriculum structure. The curriculum includes students' selective curriculum paths based on their talent and aptitude; collaborative education structure as well as multidisciplinary team-based project courses taught by groups of instructors from different disciplines. Then, the new design-engineering education program is assessed in both quantitative and qualitative ways. The first step of the research is to assess the students' core competencies required in design-engineering combined program by using K-CESA (Korea Colligate Essential Skill Assessment) with 32 students enrolled in DHE. A phenomenological study is also conducted to understand the problems in the current program via in-depth interviews with representative students in DHE. Also, a creative trans-disciplinary short course for students from other universities with various majors (e. g., engineering and design) was offered and tested to evaluate the combined educational system. Finally, we propose the direction for curriculum improvement and follow-up assessment plans, including assessments for students and faculty.open0

Perceptual difference between the discomfort luminance level and the brightness of a head-mounted display (HMD)

A psychophysical experiment was conducted to compare the discomfort luminance level and the brightness of a head-mounted display (HMD). The results showed that as the size of the HMD stimulus increased, both the discomfort luminance level of the HMD and the brightness of the HMD decreased, but the influence of the size change was more dramatic on the discomfort luminance level than on the brightness. This study showed that to provide a comfortable luminance level for HMDs, the adaptation luminance level and the size of the HMD stimulus should be considered. However, it cannot be predicted in terms of brightness

Effects of electromagnetic fluctuations in plasmas on solar neutrino fluxes

We explore the effects of electromagnetic (EM) fluctuations in plasmas on solar neutrino fluxes exploiting the fluctuation-dissipation theorem. We find that the EM spectrum in the solar core is enhanced by the EM fluctuations due to the high density of the Sun, which increases the radiation energy density and pressure. By the EM fluctuations involving the modified radiation formula, the central temperature decreases when the central pressure of the Sun is fixed. With a help of the empirical relation between central temperature and neutrino fluxes deduced from the numerical solar models, we present the change in each of the solar neutrino fluxes by the EM fluctuations. We also discuss the enhanced radiation pressure and energy density by the EM fluctuations for other astronomical objects

Evaluation of TV commercials using neurophysiological responses

Background: In recent years, neuroscientific knowledge has been applied to marketing as a novel and efficient means to comprehend the cognitive and behavioral aspects of consumers. A number of studies have attempted to evaluate media contents, especially TV commercials using various neuroimaging techniques such as electroencephalography (EEG). Yet neurophysiological examination of detailed cognitive and affective responses in viewers is still required to provide practical information to marketers. Here, this study develops a method to analyze temporal patterns of EEG data and extract affective and cognitive indices such as happiness, surprise, and attention for TV commercial evaluation. Methods: Twenty participants participated in the study. We developed the neurophysiological indices for TV commercial evaluation using classification model. Specifically, these model-based indices were customized using individual EEG features. We used a video game for developing the index of attention and four video clips for developing indices of happiness and surprise. Statistical processes including one-way analyses of variance (ANOVA) and the cross validation scheme were used to select EEG features for each index. The EEG features were composed of the combinations of spectral power at selected channels from the cross validation for each individual. The Fisher's linear discriminant classifier (FLDA) was used to estimate each neurophysiological index during viewing four different TV commercials. Post hoc behavioral responses of preference, short-term memory, and recall were measured. Results: Behavioral results showed significant differences for all preference, short-term memory rates, and recall rates between commercials, leading to a 'high-ranked' commercial group and a 'low-ranked' group (P < 0.05). Neural estimation of happiness results revealed a significant difference between the high-ranked and the low-ranked commercials in happiness index (P < 0.01). The order of rankings based on happiness and attention matched well with the order of behavioral response rankings. In the elapsed-time analysis of the highest-ranked commercial, we could point to visual and auditory semantic structures of the commercial that induced increases in the happiness index. Conclusions: Our results demonstrated that the neurophysiological indices developed in this study may provide a useful tool for evaluating TV commercialsclose0