• Journal of the Korean Society for Precision Engineering
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• v.18 no.9
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• pp.179-185
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• 2001

In this study, a visual sensor system for weld seam tracking the I-butt weld joints in GMA welding was constructed. The sensor system consists of a CCD camera, a diode laser with a cylindrical lens and a band-pass-filter to overcome the degrading of image due to spatters and arc light. In order to obtain the enhanced image, quantitative relationship between laser intensity and iris number was investigated. Throughout the repeated experiments, the shutter speed was set at 1-milisecond for minimizing the effect of spatters on the image, and therefore most of the spatter trace in the image have been found to be reduced. Region of interest was defined from the entire image and gray level of searched laser line was compared to that of weld line. The differences between these gray levels lead to spot the position of weld joint using central difference method. The results showed that, as long as weld line was within $^\pm$15$^\circ$from the longitudinal straight fine, the system constructed in this study could track the weld line successful1y. Since the processing time reduced to 0.05 sec, it is expected that the developed method could be adopted to high speed welding such as laser welding.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2008.05a
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• pp.82-85
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• 2008

A cosmetic shop in a department store is the best place in Korea's cosmetic market flow that shows the total image of each brand. The present day departmental cosmetic shops are centered around global brands and comparative brand power is competing with a small number of local brands. It is a fact that not only regarding the brand power of local brands but also the space design of their shops are different than the global brands. And, influenced by a modern society, culture, economic surrounding, the customers are getting original and individual. Their individualistic life style is demanding a shop environment with new concept. Such a sale environment is not for just product sale and a place where exchange economy of sale occurs. It is requisite for communication where total marketing strategy Is used In an active way. We must acknowledge it as a symbolic place being the ultimate site of customer oriented exchange economy showing the image of both product and the company. The aim of this plan is to set up a sale environment that will enhance the brand awareness and product value. We intended to provide purchase comfort and visual effect to the customer simultaneously with an Increase in customer attention by putting in the appropriate design requisites as per the brand specialty and by the application of a distinguished S.I.P (Store Identity Program) for the shop.

• The Transactions of the Korea Information Processing Society
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• v.4 no.8
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• pp.2133-2142
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• 1997

Compared with previous compression methods, fractal image compression drastically increases compression rate by using block-based encoding. Although decompression can be done in real time even with softwares, the most serious problem in utilizing the fractal method is the time required for the encoding. In this paper, we propose and verify i) an algorithm that reduces the encoding time by reducing the number of similarity searching on the basis of dimensional informations, and ii) an algorithm that enhances the quality of the restored image on the basis of brightness and contrast information. Finally, a method that enables fast compression with little quality degradation is proposed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.10
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• pp.1408-1416
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• 2001

Mean flow fields in the near wake of a square cylinder have been studied experimentally using a Particle Image Velocimetry (PIV). Ensemble-averaged velocity fields are successfully measured fur the square cylinder wake including the reverse flow region which arises many difficulties in accurate measurement by using conventional techniques, Experiments are performed at two free stream velocities of U$\_$$\infty$/ = 1.27m/s and 3.03m/s. The corresponding Reynolds numbers based on the free-stream velocity and cylinder diameter are 1600 and 3900, respectively. The intensity of free-stream turbulence is less than 1%, the blockage ratio (D/H) is 6.6% and the aspect ratio (W/D) is 40. The effect of Reynolds number on the near wake of a square cylinder has been investigated by the global mean velocity and instantaneous velocity fields. The most striking feature is that the length of the recirculating region increases with increasing Reynolds number, which turns out totally reverse trend compared with those observed in the circular cylinder wake at the same range of Reynolds number. Fer the case of higher Reynolds number, the mean velocity data agree well with those of relevant existing data obtained at much higher Reynolds numbers, which reflects the general aspect of sharp-edged bluff body wake.

• Imaging Science in Dentistry
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• v.40 no.2
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• pp.63-68
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• 2010

Purpose : To compare the CT numbers on 3 cone-beam CT (CBCT) images with those on multi-detector CT (MDCT) image using CT phantom and to develop linear regressive equations using CT numbers to material density for all the CT scanner each. Materials and Methods : Mini CT phantom comprised of five 1 inch thick cylindrical models with 1.125 inches diameter of materials with different densities (polyethylene, polystyrene, plastic water, nylon and acrylic) was used. It was scanned in 3 CBCTs (i-CAT, Alphard VEGA, Implagraphy SC) and 1 MDCT (Somatom Emotion). The images were saved as DICOM format and CT numbers were measured using OnDemand 3D. CT numbers obtained from CBCTs and MDCT images were compared and linear regression analysis was performed for the density, $\rho$ ($g/cm^3$), as the dependent variable in terms of the CT numbers obtained from CBCTs and MDCT images. Results : CT numbers on i-CAT and Implagraphy CBCT images were smaller than those on Somatom Emotion MDCT image (p<0.05). Linear relationship on a range of materials used for this study were $\rho$=0.001H+1.07 with $R^2$ value of 0.999 for Somatom Emotion, $\rho$=0.002H+1.09 with $R^2$ value of 0.991 for Alphard VEGA, $\rho$=0.001H+1.43 with $R^2$ value of 0.980 for i-CAT and $\rho$=0.001H+1.30 with $R^2$ value of 0.975 for Implagraphy. Conclusion: CT numbers on i-CAT and Implagraphy CBCT images were not same as those on Somatom Emotion MDCT image. The linear regressive equations to determine the density from the CT numbers with very high correlation coefficient were obtained on three CBCT and MDCT scan.

• Journal of Korea Water Resources Association
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• v.36 no.6
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• pp.985-997
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• 2003

The objective of this study is to propose Runoff Curve Numbers(CNs) for land cover and treatment classification of satellite image. For this purpose, land cover classifications by using satellite image in addition to the exiting SCS's land cover and treatment classifications studies and land cover classifications suggested by Ministry of Environment are selected to provide CNs depending on the classifications. CNs estimation method is statistical approach that is suggested by Hjelmfelt(1991). Result of this study may contribute to use efficiently for the estimation of CNs in using satellite image.

• Culinary science and hospitality research
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• v.22 no.6
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• pp.1-13
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• 2016

Since protecting the environment became a major issue in modern society, an increasing number of individuals have engaged in lifestyles of health and sustainability (LOHAS). The purpose of this study is to investigate the effects of restaurant and LOHAS images on customer satisfaction and loyalty. Particularly, this study analyzes the incremental information content of LOHAS image in the relationship between restaurant image and customer satisfaction/loyalty. A self-administered questionnaire was distributed to customers of casual-dining restaurants in three major cities (i.e., Seoul, Daegu, and Busan) in South Korea. The empirical findings suggest significant incremental information content of LOHAS image beyond general restaurant image in explaining customer satisfaction and loyalty.

• Journal of the Korean Society of Costume
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• v.59 no.2
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• pp.29-41
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• 2009

Perception between real object and recognized subject of human on objective subject is not the same. The reason Is that individual perception of visual design components are transmitted as the image of whole. It is required process of visual perception. Therefore, I developed the vision of seeing image of pattern which is based on Gestalt visual perception theory in clothes. The summary of this study's results is like followings. Extremely antagonistic terms which are specialized by formative characteristics of formative components are clearness and blur of outline/ fixed shape and non-fixed shape/ visuality and tangibility of representation/ simplicity and complexity of structure/ invariability and variability of mobility/ symmetry and asymmetry of arrangements singularity and plurality of group number. The expression of motive shows that clearness, fixed shape, visuality and simplicity pursuit Determination image, and blur, non-fixed shape, tangibility and complexity pursuit Ambiguity image. The arrangements of motive shows that invariability, symmetry and singularity pursuit Order image, and variability asymmetry and plurality pursuit Disorder image. Therefore, the standard of the coordinator of Pattern image positioning is established as Determination and Ambiguity of motive are X-axis, and Order and Disorder of pattern are Y-axis. As the frame of Pattern image positioning, four separated dimensions have made.

• Journal of the Semiconductor & Display Technology
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• v.7 no.1
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• pp.11-16
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• 2008

Confocal scanning microscopy is a widely used technique for three dimensional measurements because it is characterized by high resolution, high SNR and depth discrimination. Generally an image is generated by moving one optical probe that satisfies the confocal condition on the specimen. Measurement speed is limited by movement speed of the optical probe; scanning speed. To improve measurement speed we increase the number of optical probes. Specimen region to scan is divided by optical probes. Multi-point information each optical probe points to can be obtained simultaneously. Therefore image acquisition speed is increased in proportion to the number of optical probes. And multiple optical probes from red, green and blue laser sources can be used for color imaging and image quality, i.e., contrast, is improved by adding color information by this way. To conclude, this technique contributes to the improvement of measurement speed and image quality.

• Imaging Science in Dentistry
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• v.37 no.3
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• pp.157-163
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• 2007

Purpose: To evaluate the characteristics of (widely used) cone beam computed tomography (CBCT) images. Materials and Methods: Images were obtained with CT performance phantoms (The American Association of Physicists in Medicine; AAPM). CT phantom as the destination by using PSR $9000N^{TM}$ dental CT system (Asahi Roentgen Ind. Co., Ltd., Japan) and i-CAT CBCT (Imaging Science International Inc., USA) that have different kinds of detectors and field of view, and compared these images with the CT number for linear attenuation, contrast resolution, and spatial resolution. Results: CT number of both PSR $9000N^{TM}$ dental CT system and i-CAT CBCT did not conform to the base value of CT performance phantom. The contrast of i-CAT CBCT is higher than that of PSR $9000N^{TM}$ dental CT system. Both contrasts were increased according to thickness of cross section. Spatial resolution and shapes of reappearance was possible up to 0.6 mm in PSR $9000N^{TM}$ dental CT system and up to 1.0 mm in i-CAT CBCT. Low contrast resolution in region of low contrast sensitivity revealed low level at PSR $9000N^{TM}$ dental CT system and i-CAT CBCT. Conclusion: CBCT images revealed higher spatial resolution, however, contrast resolution in region of low contrast sensitivity was the inferiority of image characteristics.