• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.7
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• pp.2938-2956
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• 2020

Objective image quality assessment (IQA) models have been developed by effective features to imitate the characteristics of human visual system (HVS). Actually, HVS is extremely sensitive to color degradation and complex texture changes. In this paper, we firstly reveal that many existing full reference image quality assessment (FR-IQA) methods can hardly measure the image quality with contrast and masking texture changes. To solve this problem, considering texture masking effect, we proposed a novel FR-IQA method, called Texture and Color Quality Index (TCQI). The proposed method considers both in the masking effect texture and color visual perceptual threshold, which adopts three kinds of features to reflect masking texture, color difference and structural information. Furthermore, random forest (RF) is used to address the drawbacks of existing pooling technologies. Compared with other traditional learning-based tools (support vector regression and neural network), RF can achieve the better prediction performance. Experiments conducted on five large-scale databases demonstrate that our approach is highly consistent with subjective perception, outperforms twelve the state-of-the-art IQA models in terms of prediction accuracy and keeps a moderate computational complexity. The cross database validation also validates our approach achieves the ability to maintain high robustness.

• Journal of Biomedical Engineering Research
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• v.23 no.4
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• pp.301-308
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• 2002

This research was performed to analyze quantitatively how spiritual stress affects some ERPs on human through sight stimulus after the settlement of visual and auditory integration environment in three dimension space. We measured ERPs in the normal state and spiritual stress sessions separately. The subjects were 10 normal men and women and vital signs was recorded from Fpl, Fz, Cz, Pz, O1, O2's scalps. The experiment was done in isolated room where electro-magnetic effect do not affect. The result showed that P300's amplitude was a little higher under stress session and latent period in this resulted in longer time. We recorded through voltage variation the activity of brain which is in charge of human's perception. cognition, process of action and evaluated the effect of spiritual stress. We expected that the result of this research can be used to evaluate the malfunction of brain.

• Investigative Magnetic Resonance Imaging
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• v.9 no.1
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• pp.24-29
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• 2005

Purpose : Instead of conventional two-dimensional (2-D) visual stimuli, three-dimensional (3-D) visual stimuli with stereoscopic vision were employed for the study of functional Magnetic Resonance Imaging (f-MRI). In this paper f-MRI with 3-D visual stimuli is investigated in comparison with f-MRI with 2-D visual stimuli. Materials and Methods : The anaglyph which generates stereoscopic vision by viewing color coded images with red-blue glasses is used for 3-D visual stimuli. Two-dimensional visual stimuli are also used for comparison. For healthy volunteers, f-MRI experiments were performed with 2-D and 3-D visual stimuli at 3.0 Tesla MRI system. Results : Occipital lobes were activated by the 3-D visual stimuli similarly as in the f-MRI with the conventional 2-D visual stimuli. The activated regions by the 3-D visual stimuli were, however, larger than those by the 2-D visual stimuli by $18\%$. Conclusion : Stereoscopic vision is the basis of the three-dimensional human perception. In this paper 3-D visual stimuli were applied using the anaglyph. Functional MRI was performed with 2-D and 3-D visual stimuli at 3.0 Tesla whole body MRI system. The occipital lobes activated by the 3-D visual stimuli appeared larger than those by the 2-D visual stimuli by about $18\%$. This is due to the more complex character of the 3-D human vision compared to 2-D vision. The f-MRI with 3-D visual stimuli may be useful in various fields using 3-D human vision such as virtual reality, 3-D display, and 3-D multimedia contents.

• Science of Emotion and Sensibility
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• v.12 no.3
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• pp.267-278
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• 2009

Today an embodied agent generates a large amount of interest because of its vital role for human-human interactions and human-computer interactions in virtual world. A number of researchers have found that we can recognize and distinguish between various emotions expressed by an embodied agent. In addition many studies found that we respond to simulated emotions in a similar way to human emotion. This study investigates interpretation of mismatched emotions expressed by an embodied agent (e.g. a happy face with a sad voice); whether audio-visual channel integration occurs or one channel dominates when participants judge the emotion. The study employed a 4 (visual: happy, sad, warm, cold) $\times$ 4 (audio: happy, sad, warm, cold) within-subjects repeated measure design. The results suggest that people perceive emotions not depending on just one channel but depending on both channels. Additionally facial expression (happy face vs. sad face) makes a difference in influence of two channels; Audio channel has more influence in interpretation of emotions when facial expression is happy. People were able to feel other emotion which was not expressed by face or voice from mismatched emotional expressions, so there is a possibility that we may express various and delicate emotions with embodied agent by using only several kinds of emotions.

• Journal of radiological science and technology
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• v.15 no.1
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• pp.99-105
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• 1992

Visual evaluation of rib shadow and lung marking during high voltage chest radiography. The Purpose of this study is to improvement of visual discrimination of pulmonary structures on the conventional chest radiogram. The author prepared an artificial lung using an acryl plate, 8 cm in thickness, which is nearly equivalent to human lung, and 0.6 cm thickness of an aluminum plate for an artificial rib, and 0.5 cm of an acryl plate as a pulmonary vessel as well. And they were used as objects for experimental radiograms. This study performed with gradual increasing densities of film bases in the sequences of densities of 0.6, 0.9, 1.1 and 1.3. We made two combinations of images after multiple and regular cuts, with width of 1 cm, of 4 radiograms at the above mentioned densities of film bases. One image consisted of alternative combination of radiograms taken at densities of 0.6 and 1.3, and the other did at 0.9 and 1.1. The latter image provided better visual perception of pulmonary structures than the former. Experimental radiograms were also taken with 60 kV and 120 kV respectively. After careful evaluation and comparison to images taken on varieties of different densities with combinations and kV, the author had a conclusion that it is advisable to use a high kV X-ray which makes rib shadow subtle, for better visual delineation of pulmonary structures behind ribcage, eventhough contrast of pulmonary structures are decreased at high kV radiogram.

• Science of Emotion and Sensibility
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• v.26 no.1
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• pp.65-78
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• 2023

Aircraft are representative of human-machine systems. There is a delay between the human operation and the completion of the machine operation such as when the machine starts to operate and when the force is transmitted to the machine and completed. Time perception is an important component of timing tasks and is known to be affected by the anxiety associated with high arousal. This research verified the impact of weather, flight, and time conditions on the anxiety and time perception of in-service pilots in a virtual reality area. Weather conditions were divided into visual flight weather conditions and very low visibility conditions. Experiments 1 and 2 were performed with different flight and time conditions. In Experiment 1, time perception was measured by employing a button added to the control rod in the scenario of hovering and level flight with relatively little transformed in momentum and little delay. In Experiment 2, time perception was measured in the procedure of naturally taking off the helicopter by employing only the control stick in a takeoff scenario where there was a lot of transformation in momentum and a lot of delays. As a result of the experiment, it was reported that anxiety and heart rate increased in very low visibility conditions In particular, among all flight conditions in Experiments 1 and 2, it was reported that time was overestimated in the scenario of increased anxiety. This outcome can lead to overestimation of time under the impact of anxiety and failure of the timing task, which may lead to challenges in maneuvering and possibly lead to accidents.

• Journal of KIISE:Databases
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• v.36 no.5
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• pp.366-373
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• 2009

In this paper, we propose a similarity search algorithm for image databases. One of the central problems regarding content-based image retrieval (CBIR) is the semantic gap between the low-level features computed automatically from images and the human interpretation of image content. Many search algorithms used in CBIR have used the Minkowski metric (or $L_p$-norm) to measure similarity between image pairs. However those functions cannot adequately capture the aspects of the characteristics of the human visual system as well as the nonlinear relationships in contextual information. Our new search algorithm tackles this problem by employing new similarity measures and ranking strategies that reflect the nonlinearity of human perception and contextual information. Our search algorithm yields superior experimental results on a real handwritten digit image database and demonstrates its effectiveness.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1661-1663
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• 2007

The contrast of display is one of the important specifications. Even if the contrast indicates luminance range which is a capability of the display and is greater in lower luminance or higher luminance, we consider that the greater contrast gets not the better performance. It is not the same value in human visual system. In practice, it is difficult to achieve the full dynamic range seen by human beings using electronic equipment. Therefore, we consider ambient condition and human perception to calculate perceptual contrast using the CIECAM02. In this paper, we propose perceptual contrast that is calculated using the brightness of CIECAM02.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.05a
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• pp.219-222
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• 2009

Rapid object recognition is one of the main stream research themes focusing to reveal how human recognizes object and interacts with environment in natural world. This field of study is of consequence in that it is highly important in evolutionary perspective to quickly see the external objects and judge their characteristics to plan future reactions. In this study, we investigated how human detect natural scene objects and categorize them in a limited time frame. We applied Magnetoencepahlogram (MEG) while participants were performing detection (e.g. object vs. texture) or basic-level categorization (e.g. cars vs. dogs) tasks to track the dynamic interaction in human brain for rapid object recognition process. The results revealed that detection and categorization involves different temporal and functional connections that correlated for the successful recognition process as a whole. These results imply that dynamics in the brain are important for our interaction with environment. The implication from this study can be further extended to investigate the effect of subconscious emotional factors on the dynamics of brain interactions during the rapid recognition process.

• Journal of Internet Computing and Services
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• v.15 no.4
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• pp.9-20
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• 2014

Making good predictions about the outcome of one's actions would seem to be essential in the context of social interaction and decision-making. This paper proposes a computational model for learning articulated motion patterns for action recognition, which mimics biological-inspired visual perception processing of human brain. Developed model of cortical architecture for the unsupervised learning of motion sequence, builds upon neurophysiological knowledge about the cortical sites such as IT, MT, STS and specific neuronal representation which contribute to articulated motion perception. Experiments show how the model automatically selects significant motion patterns as well as meaningful static snapshot categories from continuous video input. Such key poses correspond to articulated postures which are utilized in probing the trained network to impose implied motion perception from static views. We also present how sequence selective representations are learned in STS by fusing snapshot and motion input and how learned feedback connections enable making predictions about future input sequence. Network simulations demonstrate the computational capacity of the proposed model for motion recognition.