• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.295-301
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• 2020

Radiation exposure exposed during mammography, which is performed for early examination of breast cancer, has also been suggested as a cause of carcinogenesis in the past, and scattered rays generated during examination may cause unnecessary radiation exposure to surrounding organs. In this study, the Monte Carlo simulation was used to evaluate the human organ doses exposed during conventional mammography, and to estimate the dose reduction effect for each organ when using 3D printing materials for radiation protection by scattered rays. As a result of organ dose evaluation, the breast on the opposite side of the examination was about 22.0% of the breast on the test side and about 58.6% on the eye, which was highly influenced by the scattering-ray. When using the 3D printing shield to protect it, the breast on the opposite side of the test showed an effective dose reduction effect at a thickness of 1 mm.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.11
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• pp.2125-2130
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• 2016

In this paper, we researched the excellency of 3D graphic nursery contents which is developed by mobile AR technology. AR technology has currently people's attention because of the potential to be core contents of future ICT industry. We applied AR nursery contents for kid's subtitle language selection in Korean, Chinese and English education. The original fairy tale consisted of 6~8 scenes for the 3D contents production, and was adapted and translated. Dubbing was dubbed by the native speaker using the standard pronunciation, and the effect sound was edited separately to fit the scene. After composing a scenario, constructing a 3D model, constructing a interaction, constructing a sound effect, and creating content metadata, the Unity 3D game engine is executed to create a project and describe it as a script. It provides a fun and informative tradition of fairy tales with abundant content that incorporates ICT technology, accepting advanced technology-based education, and having opportunities to perceive software in daily life.

• Journal of the Semiconductor & Display Technology
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• v.15 no.3
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• pp.46-50
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• 2016

Recently, Depending on expectancy effect and ripple effect of augmented reality, the convergence between augmented reality and culture & arts are being actively conducted. This paper proposes a learning method for effective object tracking in 3D storytelling augmented reality in cultural properties. The proposed system is based on marker-less tracking, and there are four modules that are recognition, tracking, detecting and learning module. Recognition module is composed of SURF and LSH, and then this module generates standard object information. Tracking module tracks an object using object tracking based on reliability. This information is stored in Learning module along with learned time information. Detecting module finds out the object based on having the best possible knowledge available among the learned objects information, when the system fails to track. Also, it proposes a method for robustly implementing a 3D storytelling augmented reality in cultural properties in the future.

• Journal of Digital Contents Society
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• v.11 no.2
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• pp.177-184
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• 2010

These days, as digital producing technique has been developed, 3D imaging technique is used in high-tech computer and T.V. Also study for 3D producing technique is actively in progress. Moreover, as James Cameron's movie, 'Avatar' released in 2009 was a box office hit, the issue about 3D image came to the fore again. At this point, I decided to study the effect of the visual depth caused by the color correction during the post-production stage. The purpose of this study is to offer information about processing effective images through data about the effect of the visual depth that applies the color correction during the post-production stage. Basically, I supposed that color and contract would have effects on depth of 3D image. As a result, I could find out the changes of visual depth, space perception and sense of depth throughout the experiment. Applying this result,, I produced the 15 minutes of 3D advertisement movie and I found out that the color correction during the post-production stage was very effective for 3D depth. The left image and the right image by beam splitter based rig and parallel rig were used for this study. Also I adjusted the strong contrast by the color correction during the post-production stage after correcting convergence and visual depth during editing. As a result, I could produce images which had strong sense of space and sense of depth.

• Journal of Korea Technology Innovation Society
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• v.21 no.3
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• pp.1077-1100
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• 2018

The present study analyzed the effect of firms' external research and development (R&D) on corporate productivity, while investigating the moderating effect of firm size on the external R&D-productivity nexus. In the empirical analysis, we estimated South Korean manufacturing firms' total factor productivity (TFP) using the firm level data drawn from the Survey of Business Activities (Korea National Statistical Office) for the years 2006-2015. Thereafter, focusing on the role of external R&D and its interaction with the firm size in determining firms' TFP, the productivity function was estimated as well. To this end, we used ordinary least squares (OLS) and quantile regression to highlight the heterogeneous impacts of external R&D by companies' productivity level. Empirical results confirmed that firms' external R&D significantly enhanced corporate productivity in all manufacturing industries, from high-tech to low-tech. The moderating effect of firm size in determining the productivity effect of external R&D was not as prominent as in the case for internal R&D, which exhibited some degree of the size premium in the productivity-enhancing effect. These results suggest that regardless of the firm size, external R&D can be an important channel for corporate productivity improvement, and can be a particularly effective strategy for SMEs with relatively limited internal R&D capacities.

• Journal of Technology Innovation
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• v.21 no.1
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• pp.1-26
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• 2013

The objectives of this paper are to analyze the effect of government R&D expenditure on employment in the Korean manufacturing sector in which employment is rapidly declining. According to the results of our empirical analysis, government R&D expenditure decreases the level of employment in Korean manufacturing sector in short term period, but it has positive effect on employment by compensation effect in the middle and long term period. Second, the effect of private R&D expenditure on job creation is three times larger than that of government R&D expenditure. Third, costs of labor and capital has negative effect on employment. This study is believed to help understanding the relation between R&D expenditure and employment, and providing policy implications of how to plan and manage government R&D expenditure as a tool of job creation.

• Korean Journal of Animal Reproduction
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• v.21 no.2
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• pp.197-205
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• 1997

Improved hypophysectomy technique and the efficacy of bGH in hypophysectomized female rats were studied as a basis for the function of endocrine gland and hormones. 1. With improved sublaryngeal a, pp.oach by hypophysectomy, 34 rats out of 40 were successfully hypophysectomized(more than 80% of success). The surgical time for hypophysectomy per rat was taken about 3.0$\pm$1.0 min. 2. For the effect of hypophysectomy and bGH on body weight gain among the 5 gruops of A, B, C, D, and E, the weight gains for A, B, C, D, and E, were 93g, 9.2g, 10.7g, 25.1g and 36.2g, respectively, which implied that hypophysectomy had a major effect on body weight. And also, the effect of bGH was paralleled with the level of bGH. There were significant difference between control and hypophysectomized groups, and between the bGH treated and bGH non-treated groups after hypophysectomy(p<0.01). 3. For the effect of hypophysectomy and bGH on the length of femur, tibia, humerus, and anterbrachi, longest was for A, shortest for B, and longer in order of C, D, and E. The A group was significantly longer than B, C, D, and E groups. The B group was shorter than C, D, and E groups(p<0.01). 4. For the effect of hypophysectomy and bGH on the weight of femur, tibia, humerus, and antebrachi, heaviest was for A, lightest for B, and heavier in order of C, D, and E. The A group was significantly heavier than B, C, D, and E groups. The B group was lighter than C, D, and E groups(p<0.01). 5. In changes of body length, and weights of liver and heart, A group was most drastically increased. Among the hypophysectomized groups, the change was increased in order of B, C, D, and E. Especially, the change of A group was significantly greater than B, C, D and E gruops. However, no significant differences were found among B, C, D, and E groups. 6. The hypophysectomy in rat had a significant effect on body growth. The effect of hormone was remarkably different depending upon the level of hormone. It was found that 300$\mu\textrm{g}$ of bGH/kg of body wt/day was slightly lower for normal growth.

• The Journal of the Acoustical Society of Korea
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• v.35 no.4
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• pp.310-318
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• 2016

This study deals with a method to localize a noise source occuring in a marine vehicle in a 3D environment. Even when access to the noise source is limited for a marine vehicle, such as a ship or a submarine in operation, the signal received on a hydrophone located elsewhere contains Doppler effected noise by moving relatively. This study suggests noise localization algorithm in 3D based on Doppler effect by moving marine vehicle. Using a known source mounted on the vehicle, the noise source was estimated by reducing the range of Doppler center and closest point of approach via the least square method. The algorithm was verified through various simulations and it was shown that the noise could be localized in 3D based on Doppler effect by employing two fixed hydrophones located at the vehicle's exterior points and a known reference signal generator located somewhere on the vehicle.

• Korean Circulation Journal
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• v.53 no.2
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• pp.92-102
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• 2023

Background and Objectives: YKL-40 is considered to be associated with cardiovascular disease (CVD). In this study, the effect of serum 25(OH) vitamin D [25(OH)VitD] differences between groups on YKL-40 was evaluated on a hypercholesterolemia rat model. Methods: Thirty-two male rats (wistar albino) were equally divided into 4 groups. The first group was the control group; the second group was high-cholesterol (H-CH) adequate vitamin D (VitD) group (H-Ade^VD). The third group was the H-CH deficient VitD group (H-Def^VD), and the last group was designed with the H-CH supplement VitD (H-Sup^VD). The feeding process consisted of 2 stages. At the first stage (5 months), the H-Def^VD group was fed on VitD deficient chow, while the other groups (control, H-Ade^VD, H-Sup^VD) were fed on standard chow. At the second stage (3 months), the H-Ade^VD and the H-Sup^VD groups were fed on the H-CH chow, whereas the H-Def^VD group was fed on the H-CH-VitD deficient chow. Moreover, the H-Sup^VD group was given 100 IU/kg/day VitD along with the H-CH chow. Results: Compared with the control group, interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and YKL-40 values in the H-Def^VD groups increased significantly (p<0.001, p<0.001, p=0.009, p=0.005; sequentially). Conclusion: It can be concluded that VitD can suppress the YKL-40, thus, it will prevent CVD development in rat. Therefore, further clinical studies related with human will reveal the effect of VitD and YKL-40 on CVD development.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05a
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• pp.409-412
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• 2003

The 3-D shape use to effect of movie, animation, industrial design, medical treatment service, education, engineering etc... But it is not easy to make 3-D shape from the information of 2-D image. There are two methods in restoring 3-D video image through 2-D image; First the method of using a laser; Second, the method of acquiring 3-D image through stereo vision. Instead of doing two methods with many difficulties, I study the method of simple 3-D image in this research paper. We present here a simple and efficient method, called direct calibration, which does not require any equations at all. The direct calibration procedure builds a lookup table(LUT) linking image and 3-D coordinates by a real 3-D triangulation system. The LUT is built by measuring the image coordinates of a grid of known 3-D points, and recording both image and world coordinates for each point; the depth values of all other visible points are obtained by interpolation.