• The Journal of Advanced Prosthodontics
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• v.10 no.3
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• pp.245-251
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• 2018

PURPOSE. To evaluate the accuracy of a model made using the computer-aided design/computer-aided manufacture (CAD/CAM) milling method and 3D printing method and to confirm its applicability as a work model for dental prosthesis production. MATERIALS AND METHODS. First, a natural tooth model (ANA-4, Frasaco, Germany) was scanned using an oral scanner. The obtained scan data were then used as a CAD reference model (CRM), to produce a total of 10 models each, either using the milling method or the 3D printing method. The 20 models were then scanned using a desktop scanner and the CAD test model was formed. The accuracy of the two groups was compared using dedicated software to calculate the root mean square (RMS) value after superimposing CRM and CAD test model (CTM). RESULTS. The RMS value ($152{\pm}52{\mu}m$) of the model manufactured by the milling method was significantly higher than the RMS value ($52{\pm}9{\mu}m$) of the model produced by the 3D printing method. CONCLUSION. The accuracy of the 3D printing method is superior to that of the milling method, but at present, both methods are limited in their application as a work model for prosthesis manufacture.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.779-787
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• 2023

In the relationship between the shareholding ratio of National Pension Service (NPS) and the investee firm's value, this study examined the mediating effect of R&D expenditure which its increase can indirectly induce the increase of firm value, and examined the moderated mediation effect of the Stewardship Code implementation which pressures investee firms' to increase R&D expenditure and firm value. Using the Korean listed companies' data from 2016 to 2021, the analysis showed that the R&D expenditure had a partial mediation effect on the relationship between NPS's shareholding ratio and firm value. Also, the analysis showed that the NPS's Stewardship Code implementation had positive moderating effects on following relationships, one between NPS's shareholding ratio and R&D expenditure, and the other between NPS's shareholding ratio and firm value. In all, on the relationship between NPS's shareholding ratio and firm value, the R&D expenditure's mediation effect differs before and after the implementation of the stewardship code, which shows the moderated mediation effect.

• Current Research on Agriculture and Life Sciences
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• v.7
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• pp.231-235
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• 1989

The effects of choline and choline esters(acetylcholine, methacholine, carbachol, bethanechol) on motility of isolated rabbit jejunum segment were examined and $pD_2$ values of each drugs were compared. The results were as follows. In choline, there were revealed that maximum effective concentration was $10^{-2}M$, $ED_{50}$ was $2.4{\times}10^{-3}M$, and $pD_2$ value was 2.619. In acetylcholine, there were revealed that maximum effective concentration was $10^{-4}M$, effect was hardly showin in $10^{-9}M$ concentration, $ED_{50}$ was $0.5{\times}10^{-5}M$, and $pD_2$ value was 5.154. In methacholine, there were revealed that maximum effective concentration was $10^{-5}M$, effect was hardly shown in $10^{-9}M$ concentration, $ED_{50}$ was $9{\times}10^{-7}M$, and $pD_2$ value was 6.045. In carbachol, there were revealed that maximum effective concentration was $10^{-5}M$, effect was hardly shown in $10^{-11}M$ concentration, $ED_{50}$ was $5.7{\times}10^{-7}M$, and $pD_2$ value was 6.244. In bethanechol, there were revealed that maximum effective concentration was $10^{-4}M$, effect was hardly shown in $10^{-8}M$ concentration, $ED_{50}$ was $3.3{\times}10^{-6}M$, and $pD_2$ value was 5.480. Choline and choline esters caused contraction on motility of isolated rabbit jejunum segment. The order of $pD_2$ values of drugs was carbachol, methacholine, bethanechol, acetylcholine and choline (in the descending order of potency).

• Journal of radiological science and technology
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• v.42 no.6
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• pp.441-446
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• 2019

The purpose of this paper is to recognize the usefulness of the Phantom produced with 3D printing technology by reproducing the original phantom with 3D printing technology. Using CT, we obtained information from the original phantom. The acquired file was printed by the SLA method of ABS materials. For inspection, SPECT/CT was used to obtain images. We filled the both Phantom with a solution mixed with ^99mTcO4 1 mCi in 1 liter of water and acq uired images in accordance with the standard protocol. Using Image J, the SNR for each slice of the image was obtained. As a reference images, AC images were used. For the analysis of acquired images, ROI was set in the White mater and Gray mater sections of each image, and the average Intensity Value within the ROI were compared. According to the results of this study, 3D printed phantom's SNR is about 0.1 higher than the conventional phantom. And the ratio of Intensity Value was shown in the original 1 : 3.4, and the printed phantom was shown to be 1 : 3.2. Therefore, if Calibration Value is applied, It is assumed that it can be used as an alternative to the original.

• Asia Pacific Journal of Business Review
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• v.1 no.2
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• pp.37-62
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• 2017

To analyze the effects of R&D expenditure on the firm value of Korean firms, we classified portfolios based on R&D activity levels. After that, we conducted a time-series analysis to assess excess returns from the portfolios. To carry out such an analysis, an empirical analysis of excess returns in the capital market was performed by using the monthly earning rate of stocks from 2000 to 2013. The purpose of this research is to provide basic data on investment to stakeholders in the capital market by analyzing the effects of R&D on the firm value and to overcome scholarly limitations by offering a new model of analysis. The criteria for classifying the portfolios were based on R&D expenditure levels. The analysis models follow the Fama-French Three-Factor Model and the Carhart Four-Factor Model. The analyses results are as follows. Extrapolating monthly profit rates based on R&D expenditure levels, portfolios with low R&D expenditures showed higher earning rates than those with high R&D expenditures. This suggests that high R&D expenditures did not translate into high earning rates. The investor depreciates the R&D expenditures related profitability and the possibility of success in the market, leading to falls in stock prices and a failure to give a positive effect on the firm value. Our research differs from the previous investigations as we carried out an empirical analysis based on the actual investors' attitudes about R&D expenditures and how these can generate excess earnings. Our research results show that the data related to R&D expenditure are not reflected fully in the market.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.308-311
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• 2005

Electron beam irradiation was applied to examine microbial safety and qualities of black pepper powder and commercial Sunsik. Whole black pepper powder and commercial Sunsik were irradiated at 2, 4, 8, 12, and 16 kGy. Microorganism contamination in black pepper powder and commercial Sunsik were significantly decreased by irradiation. Decimal reduction doses ($D_{10}\;value$) of total bacteria count in black pepper powder and commercial Sunsik were 5.32 and 1.56 kGy, respectively. $D_{10}\;value$ of yeast and mold were 2.54 and 2.14 kGy for black pepper powder and commercial Sunsik, respectively. Electron beam irradiation caused negligible changes in Hunter color L, a, and b values. Sensory evaluations of black pepper powder and commercial Sunsik showed no significant changes among samples. These results indicate electron beam irradiation improves microbial safety and qualities of black pepper powder and commercial Sunsik.

• Fashion & Textile Research Journal
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• v.10 no.5
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• pp.652-659
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• 2008

This study was designed to testify the possibility and devise the method to manipulate the 3D body scan data to produce rounded-belt pattern adaptable to hip-type variation of women in their 20's. The results of this research were as follows : Firstly, based on drop-value distribution of hip and waist girth, 151 subjects were classified into three hip-types; Type 1 (15.23%) was 'cylinder type', showing lowest drop-value, Type 2 (69.54%) was 'average type' and Type3 (15.23%) was 'hourglass type' showing highest drop-value. Secondly, using CAD program, design lines for round shape belt were set on the surface of 3D scan data of representative subject of each type. And divided 3D surfaces were flattened onto the plane by the internal tools of CAD program. The measure, 'lifting value of round belt pattern', implying the level of curve ratio of pattern was higher in back than front. This result might be linked to the fact that the hip part is more protruded than the abdomen part. And the measures also showed highest values in Type 3(hourglass type) and lowest in Type 1(cylinder type), meaning that the pattern of Type 3 showed more rounded shape than that of Type 1. This finding implied that round belt for body type having high drop-value should be shaped more curved. Thirdly, difference ratios of outline length and area between 3D curves(body surface) and 2D plane(pattern) were 4.5% and 1.3%, respectively. This result demonstrated and solidified the feasibility of designing digital garment pattern from 3D body scan data.

• Asia Marketing Journal
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• v.22 no.3
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• pp.1-28
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• 2020

With the development of information and communication technology and spread of smart devices, online information exchange has become a daily routine. Accordingly, the management and utilization of online word of mouth (WOM) has become an important issue for companies. Numerous studies have examined the impact of online WOM on firm performance. This study analyzes the impact of negative word of mouth (NWOM) on firm value, considering the influence of corporate social responsibility (CSR) activity and research and development (R&D) investment. Using a hierarchical linear model, we find that 1) NWOM has a negative impact on firm value, 2) CSR activities do not significantly influence this impact, and 3) R&D investment reduces this negative impact. This study contributes by demonstrating the effect of NWOM on firm value, examining the influence of CSR activities and R&D investment on the impact of NWOM, and confirming that the hierarchical linear model can be applied effectively to panel data in empirical studies. As a practical implication, companies must prevent and manage NWOM, whose impact, when caused by an unavoidable incident, can be alleviated by proactively announcing that the company is striving for competitiveness, for instance, by investing in R&D.

• Journal of Digital Contents Society
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• v.16 no.4
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• pp.645-650
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• 2015

In this paper, we propose the method for creating a stable stereoscopic 3D contents with the production guidelines by removing the excessive depth value and scene changes for high quality. We have developed a three-dimensional depth analysis tool for detecting the scene changes out of the production guidelines and the depth value changes excessively. The Scenes detected by depth analysis tool can be modified at the post production and it helps to make a stable stereoscopic 3D contents.

• Journal of Biosystems Engineering
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• v.13 no.2
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• pp.46-50
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• 1988

The estimation of beam radiation intensity on a tilted surface is very important to the design of a solar energy system. In order to get the beam radiation intensity, it is required to calculate the ratio of the diffuse solar radiation to the global radiation ($k_d$). The data measured at Chung-Buk National University. Cheong-ju, (from May 16, 1985 to Nov, 10, 1987) were analysed to define the relationship between hourly clearness index ($k_t$) and diffuse ratio ($t_d$). The results are is follow: 1. The percent of clearness index($k_t$) of less than 0.3 and of more than 0.8 were 2.7% and 3.1% respectively, and between 0.5 and 0.8 was 76.5%. 2. The regression equation between $k_t$ and $k_d$ was an exponential function as: $$k_d=\[{1\hspace{120}:\hspace{10}(k_t<0.1)\\1.28{\times}0.074^{k_t}\hspace{30}:\hspace{10}(0.1{\leq}=k_t<0.9)\\0.12\hspace{98}:\hspace{10}(0.9{\leq}=k_t)$$ There was a little difference between the result. of this study based on the data of 30 months and the results of previous study (ITRA 2(1):42-47, 1986.) based on the data of 8 months. 3. The hourly exponential regression equation between $k_t$ and $k_d$ was $k_d=A{\times}8^{k_t}$ and the values of constant A and coefficient B of the: equations are as the following table; 4. The percent of $k_d$ of less than 0.4 was 72.9% and of more than 0.7 was 6.6%. 5. Total mean value of $k_t$ and $k_d$ wert 0.56 and 0.32, respectively. From 10:00 to 15:00 o'clock the total mean value of $k_t$ was smaller that the hourly man value of $k_t$ and the one or $k_d$ larger.