• Toxicological Research
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• v.17
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• pp.323-327
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• 2001

March 19, 1999, the renovation qf the runway of the Bo-Fai ai1field in Hua Hin, Prachubk-erikhan, Thailand, unearthed chemicals which were left over from the project "anch Hand Operation" held during the Vietnam war era. The chemical mixtures were analyzed by the US EPA, the Department oj Medical Sciences (DMSc), Ministry oj Public Health (MoPH) and the Pollution Control Department (PCD), the Ministry oj Science Technology and Environment (MOSTE) of Thailand, The samples were found to contain several defoliants used in the operation. They were 2,4-D, 2,4,5-T, Dicamba, Cocydelic acid, and Dioxins. Due to the complexity of the issue, the multiplicity of possible health effects, and the socio-economic implications for imports and exports, the Thai Society of Toxicology submitted a proposal to request World Health Organization (WHO), Geneva. The assistance is for the area of chemical safety and called for immediate action to explore the magnitude qf risk involved with Dioxins. In this paper we present our approach to health risk assessment which takes into an account the epidemiological studies of high-risk group exposed to the Ranch Hand operation. Dioxins are endocrine disruption chemicals which public concerns are developed due to presumption that a hazard exists (www.eva.gov/dioxins/html) for which current methodologies are deemed insufficient. The recent concepts of how oxidative stress toxicants may affect health end points and biomarkers of exposure of exposed individuals are discussed. While research activities are undergoing, The Thai Society of Toxicology do not anticipate significant risk to local residents and the environment due to our concurrence with opinion from the international experts invited by the World Health Organization proposed to the local experts at a workshop in Bangkok.n Bangkok.

• Journal of the Economic Geographical Society of Korea
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• v.23 no.3
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• pp.209-228
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• 2020

The purpose of this study is to analyze the changes in trade and industry of Korea and suggest implications from the perspective of global value chains following the spread of COVID-19. To this end, products for prevention of epidemics which is directly related to COVID-19 and IT industries with high GVC participation were analyzed. Due to the spread of COVID-19, the variation in import and export of products for prevention of epidemics was large. In the case of masks, import and export of final goods changed drastically, but the change in intermediate goods was not significant relatively. Korea's IT industry has been differentiated according to major trading partners amid overall changes in GVCs which is summarized as higher forward participation and lower backward participation. While no particular change resulted from COVID-19 has yet been made directly, the need for diversification strategies should be taken into account at a time when the production links with China and Vietnam are close and the dependence on trade with these countries is high. The COVID-19 is still in progress, requiring corporate strategies and policy efforts to respond to changes in GVCs in the post-COVID-19 era.

• The Journal of Fisheries Business Administration
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• v.47 no.2
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• pp.15-32
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• 2016

The Association of Southeast Asian Nations(ASEAN) has been the most essential organization in Asia. In spite of the world economic crisis, Southeast Asian countries have shown fast economic growth since 2000, and they have been actively expanding investments and trades especially with major countries. Research on competitiveness in ASEAN market has spawned an increasingly large literature, but empirical research on the determinants of Korea's export to ASEAN is limited. The purpose of this study is to draw out the determinant of Korean fisheries export to ASEAN by carrying out a panel analysis. For achieving such a purpose, pooled OLS, Hausman Test, Fixed Effect, Random Effect are performed. The last 20 years' data over the period of 1995 to 2014 concentrated on the ASEAN 6 countries such as Indonesia, Malaysia, Philippine, Singapore, Thailand, Vietnam is used in this study. Amount of aquatic products export to ASEAN is used as the dependent variable; real exchange rate, real GDP, relative price level and GDP per capita are used as the explanatory variables and FTA as dummy variable. Empirical results show that fixed-effect analysis is the best model among all the models. As the fixed effect model shows, real exchange rate, real GDP, GDP per capita and dummy variable(FTA) play positive and statistically significant roles in fisheries export to ASEAN, while price variable plays a negative and statistically significant role to the dependent variable.

• The Southeast Asian review
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• v.24 no.2
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• pp.35-79
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• 2014

This study examines the measures for the activation and the growth of intra-regional trade in Southeast Asia taking a look at the four dimensions of tariff rates, non-tariff barriers, trade facilitations, and trade infrastructures. Utilizing a gravity model, we performed empirical analysis and discussed the policy implications with the priorities to implement. To expand the intra-regional trade in Southeast Asia it would be necessary to enhance the level of trade facilitations and provide trade infrastructures, such as ports and airports as well as cutting the tariff rates and eliminating the non-trade barriers. In particular, in the case of exports of ASEAN6 to ASEAN6 the infrastructure is the important factor. Also, in the case of the exports of ASEAN6 to CLMV(Cambodia, Laos, Myanmar, and Vietnam), it is expected that eliminating non-tariff barriers and enhancing trade facilitations may play important roles in the progress of intra-regional trade. These results may provide the important implications for Southeast Asian countries, which are trying to promote intra-regional trade ahead of the constitution of ASEAN Economic Community by 2015. Southeast Asian countries could be evaluated to achieve a certain level of trade liberalization and economic integration through the formation of AFTA. But in order for Southeast Asia to develop to advanced economic integrated region it requires mutual cooperations and policy harmonizations among regional countries. Also, for the elimination of non-tariff barriers, promoting trade facilitations, and providing infrastructures, the administrative, legal, and institutional measures would have to be fulfilled in advance. In addition, capital investment for constructing infrastructures would be necessary to realize the intra-regional trade expansion. However, to achieve the goal, it would require a large capital investment and highly mandated policy considerations and harmonizations among Southeast Asian countries in terms of further trade liberalization and economic integration.

• Korean Journal of Comparative Education
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• v.27 no.4
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• pp.23-44
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• 2017

The purpose of this study is to review the trend in comparative education research related to curriculum published in the Korean Journal of Comparative Education, and to critically analyze its characteristics from the postcolonial perspectives. In this study, I analyzed 61 articles published in this journal from 1995 to 2016. The result showed that comparative studies related to curriculum were conducted mainly by benchmarking policies or contents related to curriculum and textbooks of Western countries including North America and Europe as well as Japan which colonized Korea. In addition, although Korea has been changing into multicultural society, studies on Asian countries such as China and Vietnam which are the nationalities of many foreigners living in Korea were rare. Based on the results, this study suggested that the expansion of comparative education research subjects, overcoming of coloniality in comparative education, and ontological reflection of comparative education researchers are necessary.

• Transactions of Materials Processing
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• v.31 no.6
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• pp.351-364
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• 2022

The yield criterion, or called yield function, plays an important role in the study of plastic working of a sheet because it governs the plastic deformation properties of the sheet during plastic forming process. In this paper, we propose a modified version of previous anisotropic yield function (Trans. Mater. Process., 31(4) 2022, pp. 214-228) based on J2 and J3 stress invariants. The proposed anisotropic yield model has the 6th-order of stress components. The modified version of the anisotropic yield function in this study is as follows. f(J₂⁰,J₃⁰) ≡ (J₂⁰)³ + α(J₃⁰)² + β(J₂⁰)^3/2 × (J₃⁰) = k⁶ The proposed anisotropic yield function well explains the anisotropic plastic behavior of various sheets such as aluminum, high strength steel, magnesium alloy sheets etc. by introducing the parameters α and β, and also exhibits both symmetrical and asymmetrical yield surfaces. The parameters included in the proposed model are determined through an optimization algorithm from uniaxial and biaxial experimental data under proportional loading path. In this study, the validity of the proposed anisotropic yield function was verified by comparing the yield surface shape, normalized uniaxial yield stress value, and Lankford's anisotropic coefficient R-value derived with the experimental results. Application for the proposed anisotropic yield function to AA6016-T4 aluminum and DP980 sheets shows symmetrical yielding behavior and to AZ31B magnesium shows asymmetric yielding behavior, it was shown that the yield locus and yielding behavior of various types of sheet materials can be predicted reasonably by using the proposed anisotropic yield function.

• Transactions of Materials Processing
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• v.31 no.4
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• pp.214-228
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• 2022

The yield criterion, or called yield function, plays an important role in the study of plastic working of a sheet because it governs the plastic deformation properties of the sheet during plastic forming process. In this paper, we propose a novel anisotropic yield function useful for describing the plastic behavior of various anisotropic sheets. The proposed yield function includes the anisotropic version of the second stress invariant J₂ and the third stress invariant J₃. The anisotropic yield function newly proposed in this study is as follows. F(J₂)+ αG(J₃)+ βH (J₂ × J₃) = k^m The proposed yield function well explains the anisotropic plastic behavior of various sheets by introducing the parameters α and β, and also exhibits both symmetrical and asymmetrical yield surfaces. The parameters included in the proposed model are determined through an optimization algorithm from uniaxial and biaxial experimental data under proportional loading path. In this study, the validity of the proposed anisotropic yield function was verified by comparing the yield surface shape, normalized uniaxial yield stress value, and Lankford's anisotropic coefficient R-value derived with the experimental results. Application for the proposed anisotropic yield function to aluminum sheet shows symmetrical yielding behavior and to pure titanium sheet shows asymmetric yielding behavior, it was shown that the yield curve and yield behavior of various types of sheet materials can be predicted reasonably by using the proposed new yield anisotropic function.

• The Journal of Fisheries Business Administration
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• v.53 no.2
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• pp.21-41
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• 2022

The effect of change in exchange rates on an economy is very important, especially, to a small open economy like South Korea. I explore whether Free Trade Agreements (FTAs) have positive influences on exchange rate-pass through import price of import market for fishery products in South Korea. Competition among FTA partners is enhanced after FTAs are effective. I expect that the extent to which are exchange rate pass-through (hereafter, ERPT) into import price of fishery products (in terms of Korea currency) would be reduced since the import market for fishery products in South Korea is an oligopolistic market. Specifically, I investigate two research questions with six South Korea's FTA partners-Norway, Thailand, Peru, U.S., China and Vietnam. First, whether the extent to which are exchange rate pass-through into import price of fishery products from six FTA partners would decrase in the post-FTA era; seconds, the size of reduction has a negative relation with the size of their market share in the import market for fishery products in South Korea if it decreases. The empirical results indicate that the degree of ERPT into import price from other FTA partners than Norway has been reduced after FTA, statistically and significantly; however, I do not find the evidence that the size of reduction is related to their market share. The findings in this study imply that FTAs have negative effects on producers' economic welfare in South Korea's fishery industry by reducing the extent to which are exchange rate pass-through as well as reducing tariff barriers.

• Journal of Preventive Medicine and Public Health
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• v.34 no.1
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• pp.80-88
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• 2001

Objectives : In an epidemiologic study on the health impact of Agent Orange exposure, the valid estimation of exposure level is the most important step. Based on recent studies, we examined the correlation between exposure levels categorized by personal exposure estimates and serum 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD, Dioxin), exploring the possibility of utilizing the exposure level as a surrogate for the estimate of exposure to agent orange. Methods : During the study period (Jan 1996-Feb 1996), blood specimens of 745 subjects taken randomly among 1,329 persons and kept frozen, were analyzed for 2,3,7,8-TCDO and six other dioxin congeners. The serum dioxin and congeners were measured in 1998 by CDC, adjusted for serum lipids. We categorized the total exposure scores into five groups based on Agent Orange exposure data collected by interview and military records. Pearson and Spearman's correlation coefficients & multiple regression analysis were used to identify the relationship of the exposure level categorized with serum concentration of 2,3,7,8-TCDD, and six other dioxin congeners. Results : Dioxin and the other congeners, except 1,2,4,6,7,8-HpCDD, showed significant correlations to exposure categories (p<0.005): 2,3,7,8-TCDD and OCDD showed positive correlations, whereas the other congeners did negative. The values of 2,3,7,8-TCDD differed according to exposure category and proportionally increased from the low exposure group to the high, a dose-response relationship, even after other possible confounding variables were adjusted for. In multiple regression analysis, age$(\beta=0.033)$, dioxin$(\beta=0.433)$, 1,2,3,7,8-PeCDD$(\beta=-0.998)$, 1,2,3,4,7,8-HxCDD$(\beta=-0.773)$, 1,2,3,6,7,8-HxCDD$(\beta=0.255)$, 1,2,3,7,8,9-HxCDD$(\beta=-3.468)$, 1,2,3,4,6,7,8-HpCDD$(\beta=0.109)$ we re found to be significantly related to the total exposure score(p<0.005). Conclusion : This study demonstrated that the use of such categorizations as a surrogate measure of agent orange exposure in identifying exposure degrees in a health impact study is valid.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.354-364
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• 2020

This study was conducted to examine the potential of inducing salinity stress on cylindrical paper pot tomato seedlings to inhibit overgrowth. Potassium fertilizers, sulfate of potash (K₂SO₄), muriate of potash (KCl), and monopotassium phosphate (KH₂PO₄), were prepared as two solutions of (5 and 10) dS·m^-1 salinity level, respectively, to investigate the influence on tomato (Lycopersicon esculentum Mill.) seedling growth. We also investigated the adaptability and survivability of treated tomato seedlings with high-salinity potassium (10 dS·m^-1 KCl) to harsh environmental conditions (water deficit, low temperature, and storage conditions). Repeated addition of high-salinity level KCl, K₂SO₄, or KH₂PO₄ markedly decreased the dry matter of shoot and root, leaf area, and net assimilate rates (NAR) but increased the stem diameter of seedlings. Among the three sources, the relative growth rate of plant height (RGR_H) was most sensitive to KCl addition; increasing salinity levels of KCl solution decreased the RGR_H of seedlings. The compactness, which directly reflects the stocky growth index, increased in KCl or KH₂PO₄ treatments. After a week's water deficit, severely wilted seedlings were observed in control seedlings (untreated with KCl), but no wilted seedlings were observed in the KCl treated seedlings, and the relative water content (RWC) of the untreated seedlings significantly decreased by 23 %, while that of the pretreated seedlings only decreased by 8 %. The increase in ion leakage of KCl treated seedlings at low temperatures was less than that of untreated seedlings. Furthermore, there was far lower damage proportion on pretreated seedlings at (9, 12, and 15)℃ storage temperatures after 20 days, compared with on unpretreated seedlings. Our results suggest that high-salinity potassium fertilizer, especially KCl, is effective in preventing tomato seedling overgrowth, while it also improves tolerance.