• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1745-1750
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• 2013

A novel green aqueous mobile phase modified with room temperature ionic liquids (RTILs) was employed in the absence of volatile organic solvents or ion-pairing reagents to analyze thiamine, a very polar compound, by reverse phase high performance liquid chromatography (RP-HPLC). Due to its strongly hydrophilic nature, thiamine was eluted near the column dead time ($t_0$) using a mobile phase without adding RTILs or ion-pairing reagents, even if a 100% aqueous mobile phase, which has weak elution power under reverse phase conditions, was used. Thus, 1-ethyl-3-methyl-imidazolium hexafluorophosphate ([EMIM][$PF_6$]), which has the strongest chaotropic effect, was selected as a mobile phase additive to improve retention and avoid baseline disturbances at $t_0$. Various mobile phase parameters such as cation moiety, chaotropic anion moiety, pH and concentration of RTILs were optimized to determine thiamine at the proper retention time. Method validation was performed to assess linearity, intra- and inter-day accuracy and precision, recovery and repeatability; all results were found to be satisfactory. The developed method was also compared to the current official United States Pharmacopoeia (USP) and Korean Pharmacopoeia (KP) methods using an organic mobile phase containing an ionpairing reagent by means of evaluating various chromatographic parameters such as the capacity factor, theoretical plate number, peak asymmetry and tailing factor. The results indicated that the proposed method exhibited better efficiency of thiamine analysis than the official methods, and it was successfully applied to quantify thiamine in pharmaceutical preparations.

• The Korea Journal of Herbology
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• v.29 no.6
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• pp.35-43
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• 2014

Objectives : Official Arisaematis Rhizoma is described only three species, Arisaema amurnse, Arisaema erubescens, and Arisaema heterophyllum, in national Pharmacopoeia. However, other Arisaema species, Arisaema ringens, Arisaema takesimense and Arisaema serratum, also have been distributed as an inauthentic Arisaematis Rhizoma in the herbal market. To develop a reliable molecular authentication method for Arisaematis Rhizoma in species level, we analyzed DNA barcode regions using six Arisaema species. Methods : Thirty-eight samples of six Arisaema plants species (A. amurense, A. amurense f. serratum, A. heterophyllum, A. takesimense, and A. serratum) were collected from different habitate and nucleotide sequences of DNA barcode regions (rDNA-ITS, matK, and rbcL gene) were analyzed after PCR amplification. The species-specific sequences and phylogenetic relations were estimated using entire sequences of three DNA barcodes based on the analysis of ClastalW and UPGMA, respectively. Results : The comparative analysis of DNA barcode sequences were revealed inter-species specific nucleotides to distinguish the medicinal plant of Arisaema Rhizoma in species levels excluding between A. amurense and its subspecies (A. amurense f. serratum) and A. takesimense and A. serratum, respectively. However, we obtained sequence differences enough to discriminate authentic and inauthentic Arisaematis Rhizoma. Therefore, we suggest that these SNP type molecular genetic markers were an reliable method avaliable to identify official herbal medicines. Conclusions : These marker nucleotides could be useful to identify the official herbal medicines by providing definitive information that can identify original medicinal plant and distinguish from inauthentic adulterants and substitutes.

• Journal of Korea Trade
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• v.26 no.8
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• pp.37-57
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• 2022

Purpose -International diplomacy is key for the cohesive economic growth of countries around the world. This study aims to identify the major topics discussed and make sense of word pairs used in sentences by Chinese senior leaders during their diplomatic visits. It also compares the differences between key topics addressed during diplomatic visits to developed and developing countries. Design/methodology - We employed three methods: word frequency, co-word, and semantic network analysis. Text data are crawling state and official visit news released by the Ministry of Foreign Affairs of the People's Republic of China regarding diplomatic visits undertaken from 2015-2019. Findings - The results show economic and diplomatic relations most prominently during state and official visits. The discussion topics were classified according to nine centrality keywords most central to the structure and had the maximum influence in China. Moreover, the results showed that China's diplomatic issues and strategies differ between developed and developing countries. The topics mentioned in developing countries were more diverse. Originality/value - Our study proposes an effective approach to identify key topics in Chinese diplomatic talks with other countries. Moreover, it shows that discussion topics differ for developed and developing countries. The findings of this research can help researchers conduct empirical studies on diplomacy relationships and extend our method to other countries. Additionally, it can significantly help key policymakers gain insights into negotiations and establish a good diplomatic relationship with China.

• Analytical Science and Technology
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• v.23 no.3
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• pp.261-268
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• 2010

This study was performed to evaluate the PCBs-containing wastes using official test method. Ninety samples of transformer oil and various solid waste were collected to assess the analytical results. In the analysis of PCBs-containing wastes, the PCBs levels were detected in the range of 7.6 mg/kg to 23.8 mg/kg for transformer oils, $0.02\sim0.54\;{\mu}g/100cm^2$ for plat solid wastes, and 0.01~0.071 mg/kg for amorphous solid waste. In the cupper wire waste of the transformer with oil concentration level of 23 mg/kg, the analytical result exceed PCBs regulation level of 0.04 mg/kg. The new proposed analytical method for PCBs containing waste can be forced to effective management of the wastes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.342-351
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• 2016

This study was carried out to develop an optimized analytical method using high-performance liquid chromatography (HPLC) applied to canthaxanthin, which is not yet designated as a food colorant in Korea, as well as to perform validation and uncertainty evaluation of this method. Official methods of AOAC, UK, and Japan with HPLC-UV detection were evaluated for the analysis of canthaxanthin by comparison of linearity, resolution, selectivity, limit of detection (LOD), limit of quantitation (LOQ), accuracy, precision, recovery, inter-laboratory tests, and uncertainty measurement. The calibration curves showed high linearity with an $R_2$ value of over 0.999 for canthaxanthin standard solutions in all three official methods. The official method of Japan exhibited the best results in terms of resolution and selectivity, including the lowest LOD and LOQ. The average coefficients of variation were calculated as less than five of three institutes with a precision value less than 1, accuracy near 100%, and recovery ratio between $100{\pm}10%$. The expanded uncertainty for canthaxanthin was estimated to be $39.5{\pm}5.29mg/kg$ (95% confidence level, k=2), and the uncertainty of measurement was 13.4%. In this study, official methods of canthaxanthin were compared and the validities verified. The results will be further applied to establish an authorized analytical method for canthaxanthin in Korea.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.339-345
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• 2011

BACKGROUND: Recently in Korea, the import of agricultural products is rising due to the increasing amount of trade. Unregistered pesticides, allidochlor, propachlor, propham, cycloate, diallate and pebulate are widely used as pesticides for rice cultivation in foreign countries, while they are not registered in Korea. Therefore, the residue amount of imported agri-foods should be verified using the proper official analytical method for each of them that has not registered in Korea. METHODS AND RESULTS: This work was conducted to apply the official method of Korea Food & Drug Administration (KFDA) for determining multi class pesticide multiresidues in agricultural commodities. Brown rice and orange which have different characteristics as a matrix were selected as representative samples for residue analysis. The recoveries of cycloate, diallate and pebulate by GC/MS in fortified brown rice and orange with levels of 0.04~0.4 mg/kg were ranged from 82.8% to 110.3%. The quantification limits of three pesticides in brown rice and orange were 0.04 mg/kg. CONCLUSION: As a result, this method can surely be used as an official method for routine analysis of unregistered pesticides in Korea for imported agri-food.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.1-4
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• 2015

The current official perfluorochemicals (PFCs) analysis method is established with hydrophilic-lipophilic balance (HLB) solid phase extraction (SPE) clean-up method with LC-tandem mass spectrometry ($MS^n$). Herein the HLB clean-up method from the official method by Korean government was modified with Envi-Carb$^{TM}$ to improve the clean-up efficiency for agricultural water and the unexpected UV disturbance in the water was effectively removed by the adsorbent treatment without a significant disturbance of quantitation. And quadrupole time of flight mass spectrometry (qTOFMS) was suggested to the available $MS^n$ instruments for the residue analysis of PFCs based on the ng/L of quantitation limits in water as well.

• Journal of Cadastre & Land InformatiX
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• v.50 no.1
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• pp.87-105
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• 2020

The government is trying to secure reliability by raising the accuracy, objectivity, and transparency of the official price by promoting the reliability improvement plan of the official price and increasing the realization rate, but the Realization rate of Publicly Notified Individual Land Price is showing a big difference because the current market price is not fully reflected in the official price. Therefore, this study collected the actual transaction price reported to the RTMS in Wansan-gu, Jeonju, Jeollabuk-do and the individual official price of the KRAS and calculated the realization rate of publicly notified individual Land Price. SPSS 25.0 program was used for the empirical analysis of this study. The Dependent Variable was the realization rate of publicly notified individual Land Price, and Independent Variables, was six land characteristics items were selected, one-way ANOVA was conducted and post-test was conducted by Scheffe method. As a result of the analysis, average difference in realization rate of publicly notified individual Land Price was found in Residential areas, Commercial areas, and Farmland, Public land and Residential and commercia, Residential and Forest. Especially, it was found that the price of commercial area is higher than that of residential area and green area, and the price is less reflected in individual official land price.

• Journal of Fashion Business
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• v.24 no.1
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• pp.75-87
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• 2020

The purpose of this study is to find trends in new media fashion content by analyzing the fashion content of the official Instagram accounts of domestic fashion magazines that are being transformed by digital media. The framework for these analysis of fashion content type and methods of production is based on one used in an earlier research project. Empirical analysis is conducted on Vogue Korea's official Instagram accounts, using the highest number of major views as the secondary measure of interest. After screening for fashion content in posts on the Vogue Korea account for four months, 291 short video postings were extracted to analyze the number of views the postings received. The results were categorized as 'star', 'show/exhibition', 'product', 'shop', 'fashion film', 'designer', or 'event', included in the data are the number of postings by type and the number of views by post. Based on the characteristics of the creator and the editing, the posts were classified into 'professional production highlight', 'professional production private', 'UCC' or 'GIF' videos, the number of views per post were also collected. The research results show different levels of interest depending on the type of fashion content, and also on the way the videos were produced. The study also investigated how the combination of these two factors affects interest. When producing a new media fashion content, combining a 'star' type post with 'professional production private' video content was most popular. The selection of production method is therefore important even given the same type of content.

• Journal of Distribution Science
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• v.12 no.11
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• pp.25-34
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• 2014

Purpose - Considering that the governments' official statistics on the optimum scale of the domestic service industry will be crucial in future, this study's results will be used as an important benchmark to develop and verify the parameters in the government's official statistics. Research design, data, and methodology - To identify the appropriate scale of Korea's service industry and its adequacy, I have determined them through estimation using a regression method involving panel data analysis on the panel data of 30 OECD countries. Results - The regression coefficient provided indications of being non-linear. This means that a U-shaped curve relationship exists-that is, the level of the economic growth leverage decreases along with the service industry's growth up to the level of 70.9% in terms of the Korean service industry's adequacy; it increases along with the service industry's growth at a level higher than 70.9%. Conclusions - While the current proportion of the size of the service industry among all industries in Korea stands at 50.7%, its proper proportion estimated by a regression analysis was 70.9%.