• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.2
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• pp.96-103
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• 2011

Rotor grip is used as a component of rotor system in unmanned helicopter. Instead of usual machining, hot forging process has been considered to improve its proof stress against repeated loading conditions and crash in the farm-field. Die design and forming analysis have been performed according to the conditions such as billet volume, flash, cavity filling, and the distribution of damage during the forming by using FE analysis. In the results of analysis, the possibility of structural failure in the model has not been found because its maximum effective stress is much lower than yield strength of the titanium alloy. In the forging die design, flash has been allowed because of low production in the industrial field. Preform design was studied by using FE-analysis, and its optimal dimension was obtained in the hot forging of rotor grip with titanium alloy.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2008.04a
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• pp.5-13
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• 2008

The aquatic fern Azolla spp. is of value as a bio-fertilizer for wetland paddy, and also can be used as an ideal feed for cattle, pigs and poultry. It is popular and cultivated widely in other countries like China, Vietnam, and the Philippines, but has yet to be taken up in Korea, in a big way. It fixes nitrogen as high as 3-5kg N per day, because it contains nitrogen fixing blue-green algae, Anabaena azollae. Azolla's ability to create a light-proof mat that suppresses other weeds has been used for centuries in rice production. Azolla spp. has also the capacity to take up the heavy metals ($75{\sim}100%$) and may be used as a bioaccumulator. Moreover, Azolla meal as an unconventional feed resource has a potential as a feedstuff for livestock.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.1
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• pp.111-116
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• 2001

A practical scheme to reduce failure of the PCB(Printed Circuit Board) of a monitor is introduced using deformed mode shape under mechanical shock. When the monitor is given critical shock loads, cracks are commonly initiated at the tip of a hole on the PCB. Accordingly, a deformed mode shape of the PCB is obtained using a FEM code to define a weak point on the PCB under mechanical shock, and then the position and direction of the hole is determined to prevent the failure at the critical mode shape. Also, the stress intensity factor around the weak point on the PCB is calculated to check the possibility of fracture by normal tensile stress. In conclusion, present research is useful to assist the practical design of components-layout on the PCB.

• Korean Journal of Plant Resources
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• v.21 no.3
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• pp.230-235
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• 2008

The aquatic fern Azolla spp. is of value as a bio-fertilizer for wetland paddy. It is popular and cultivated widely in other countries like China, Vietnam, and the Philippines, but has yet to be taken up in Korea, in a big way. It fixes nitrogen as high as 3-5kg N per day, because it contains nitrogen fixing blue-green algae, Anabaena azollae. Azolla's ability to create a light-proof mat that suppresses other weeds has been used for centuries in rice production. Azolla spp. has also the capacity to take up the heavy metals such as Mercury and Chromium (75${\sim}$100%) and may be used as a bioaccumulator in the phytoremediation. Azolla meal also can be used as an unconventional feed resource has a potential as a feedstuff for livestock.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.5
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• pp.25-32
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• 2019

The purpose of this study is to investigate how to make a proper investment in ICO in the market. Previously, companies used to borrow money from banks or to obtain investments from venture capital (VC) and angel investors, but now ICOs are used as a new type of funding and financing model. The ICO sells the tokens or coins created on the blockchain openly online to raise the necessary funds, and provides the market value by paying the tokens or coins as much as the investment amount. According to this study, the limitations of the ICO market are (1) difficulties in evaluating the company, (2) uncertainties in investments, (3) lack of legal safeguards, and (4) measures to secure corporate stability after recruitment. At present, there is no way to cope with this systematically since the ICO is not protected in the legal framework. Nevertheless, we investigated the ways to make proper investment in the existing ICO market. In investing in ICO, investors should (1) consider investment methods and profitability, and (2) verify and judge investment fraud through various channels (ex. Homepage, composition team profile, etc.) and make investments based on this. This study will contribute to the formation of a healthy ICO market by understanding the newly emerged ICO market and studying the considerations when investing in it, thereby contributing to the right investor training and reducing the mass production of consumer damages caused by fraud. The limitation of this study is that the domestic ICO has not yet been examined in the legal framework, so further research is needed when policy changes occur in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.392-402
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• 2018

Citrus fruits can be classified as field citrus, greenhouse citrus, citrus produced by rain proof cultivation and late-harvested citrus such as Hallabong, Chunhaehyang, and Jinjihyang according to cultivation method or variety in Jeju province of Korea. The consumption of late-harvested citrus has been increasing steadily since 1990 because the sugar content of the fruits is ordinary higher than field citrus. The cultivation land of citrus produced by rain proof cultivation has been also enlarged continuously aided by Korean government support program and quality increasing effect of this cultivation method. However, the cultivation land of field citrus has been decreasing since 2010. In spite of such a decrease of cultivation land, recently the price of field citrus rather declined according to increasing of yield per 10a. For the estimation and forecast of the long-term supply-demand model in the field citrus, we constructed a partial balance model for the individual field citrus and estimated individual equation in each item's model by using the econometric method. As a result of the production storage scenario analysis, the cultivation area is expected to store 5%(14.49ha), 10%(14.97ha). 15%(15.50ha) of citrus production in 2027. This study reviews the structure of storage, and storability in Jeju field citrus and suggest several policy implications.

• The Journal of Fisheries Business Administration
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• v.39 no.1
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• pp.133-162
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• 2008

In 1970, direct overseas investment in Korean fisheries started to sell the frozen marine products to Singapore with establishing local subsidiary. Direct overseas investment in China has carried out since Korea and China established diplomat relationship in 1992. the former day, The Korea invested indirectly in China via Hong Kong. It has reported that 253 local subsidiaries applied to China government permit at the end of 2004. The results will make a decision on whether to invest continuously. The results of actual proof analysis has announced that a successful investment of fishery company is mainly influenced in its own government policy. Many advantages of tax and administration for foreign company in China have been changed and vanished comparing to the beginning time of entering china. So. it is imperative for Korean government to take measures to changing policy of Chinese government. The early days, investment of fishery company is type of resources and abundant resources will affect succeeding investment. Nowadays, the type of the investment is the production oriented investment. And then many direct investment linked the production oriented investment have been conducted in many area in China. So. the production oriented investment will affect logistics and successful investment in China. And, The factor of Market potential in Market Factors in the middle of changing market oriented investment will conclude whether to invest. As the china exchange system changed from the fixed exchange system to the fluctuating exchange system. Risk of exchange rate will affect corporate's parent business. The local risk (regulation of import and export, remittance) will affect succeeding investment of corporate's parent.

• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.397-404
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• 2002

Soybean curd residue (SCR) was fermented by lactic acid bacteria, Lactobacillus rhamnosus LS and Entercoccus faecium LL, isolated from SCR. The pH, titratable acidify and viable cell counts were determined from the fermented SCR to evaluate the lactic acid production and growth of lactic acid bacteria. Optimal amounts of pretense enzyme and glucose, and ideal fermentation time for SCR fermentation were estimated by response surface methodology (RSM). Raw SCR fermented by indigenous microorganisms had 0.78 % titratable acidity, The acid production in SCR fermented by L. rhamnosus LS was greatly enhanced by the addition of glucose and lactose. However only glucose increased acid production by Ent. faecium LL. The proof test of SCR fermentation demonstrated that similar results for titratable acidity, tyrosine content and viable cell counts to that predicted could be obtained by the at optimized fermentation conditions. In the presence of 0.029 % (w/w) pretense enzyme and 0.9% (w/w) glucose, the SCR fermented by Ent. faecium LL showed 1.07% (w/v) of titratable acidity, 1.02 mg% tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts. With the SCR fortified with 0.033% pretense enzyme and 1.7% glucose, L. rhamnosus LS showed 1.8% (w/v) of titratable acidity, 0.92 mg% of tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts.

• Herbal Formula Science
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• v.20 no.2
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• pp.65-82
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• 2012

Objectives : The aim of this study was verification of the anti-oxidative and anti-inflammatory effects of Odukhwan(ODH) and Sasinhwan(SSH) in mouse macrophage, RAW264.7 cells. Methods : To investigate the anti-oxidative effect and scavenging activities of DPPH radical, superoxide anions, nitric oxide and peroxynitrite were measured. Cytotoxic activity of extract of ODH and SSH on RAW264.7 cells was measured using MTS assay. To proof the reductive activity of intracellular oxidation, DCFH-DA assay was performed. The nitric oxide(NO) production was measured and pro-inflammatory cytokines and $PGE_2$ were measured by ELISA kit. The levels of inducible nitric oxide synthase(iNOS), cyclooxygenase-2(COX-2) and nuclear NF-${\kappa}B$ p65 expression were detected by western blot. Results : After those analyses, we bring to a conclusion as follows. Both herbal formulations scavenged DPPH radical and nitric oxide. But ODH had no scavenging activity of superoxide anions and SSH had low scavenging activity in peroxynitrite. And the results indicated that ODH and SSH inhibited the LPS-induced NO, $PGE_2$ production and iNOS, COX-2 expression accompanied by an attenuation of IL-$1{\beta}$ and IL-6 production in RAW264.7 cells. They also have suppression effects of LPS-induced NF-${\kappa}B$ activation. Conclusions : ODH and SSH have anti-oxidative and anti-inflammatory effects and they may be a part of database for development of new anti-oxidative and anti-inflammatory drugs.

• Korea Trade Review
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• v.46 no.1
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• pp.1-21
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• 2021

The main purpose of this research is to analyze the changes in investment motivation by year through time series and cross-sectional analysis of the factors and investment decisions of Korean manufacturing companies. According to the investment pattern for Asean from the 1980s to the 19th, the first expansion period was 82 to 86, the average increase in overseas investment for securing foreign raw materials due to the second oil shock, and the second expansion period was a gradual increase in exports to the U.S. in 1987 to 1996. During the first stagnation period, direct investment in Asean stagnated in the aftermath of the 1998-05 Asian crisis, and in the third expansion period, part of the production facilities invested in China were relocated to Asean, increasing Asean's investment to become Korea's largest manufacturing investment in 17. Korea's proportion of investment in Asean surpassed that of mass investment since 10 years ago, and the proportion of investment in manufacturing sector has been transferred from China to Asean, and after 17 years, it has served as an overseas production base connecting China. As such, The main purpose of the research will be to extract the determinant factors and key factors for overseas direct investment and investment patterns in conjunction with global manufacturing companies' production base relocation and investment trends through empirical analysis. This research paper gave basic reference to the motivation and determinant of investment 16 years ago, and analyzed the changes in investment motivation by year and content through empirical analysis, contributing some reasonable purpose to the decision of companies and policy makers interested in overseas direct investment.