• 대한공업교육학회지
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• v.33 no.2
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• pp.192-217
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• 2008

This paper investigated the perceived criticalities and patterns of Korean Professional Engineer's competency regarding the working activities of automative product development, manufacturing, etc by using questionnaires responded to the survey which were applied to the automotive professors, experts and professional engineers (vocational parties) by e/mail, etc. This research investigated the following questions: First, what are the characteristic patterns, relevancy and perceived criticalities of Korean Professional Engineer's competencies? Second, What are the ranked priority of the Korean Professional Engineers' competencies? Are there any differency for each item, sub group of job, intelectual criterior of the competencies between relevancy and perceived criticalities according to the types of vocational parties, etc.? Accoring to the results; first, Professor group showed highest points among 3 groups per each item of the competencies by vocational parties Second, Chassis design group ranked top position among the 8 sub groups by vocational parties and, third, Problem Solving Knowledge ranked highest points than any others. Korean Professional Engineers are found to be positioned as key members, leaders and managers on surveying market, product planning, designing product & components, developing component parts, establishing shop with production equipment, managing quality control & material handling, organizing relevant meetings, developing human resources by training and learning, to back up finance with law matters, cooperating with concerned parties to achieve organizational goals, and to coordinate projects. etc, identifying ethical issues and business skills in order to survive and win to be competitive in various kinds of the automotive industry battle fields.

• Journal of Life Science
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• v.22 no.8
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• pp.1099-1106
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• 2012

The cytotoxicity of the colorant in conjugated linoleic acid (CLA) was investigated in human cancer cell lines and a normal human cell line. Commercially-available CLA with a brown color (designate crude CLA; c-CLA) was distilled in a vacuum (10 mmHg-$220^{\circ}C$, 10 mmHg-$235^{\circ}C$, 10 mmHg-$240^{\circ}C$, and 20 mmHg-$260^{\circ}C$) for 30 min to obtain pure CLA (distilled CLA; d-CLA) and dark brown-colored CLA (residual CLA; r-CLA) samples. No color intensity was shown in the d-CLA sample obtained under 10 mmHg-$220^{\circ}C$ conditions of distillation when the L (brightness), a (red/blue), and b (yellow/green) parameters were analyzed, whereas the r-CLA sample showed a dark brown color. The composition of CLA isomers in both the d- and r-CLA samples, as compared to that of the c-CLA sample, was not significantly different when analyzed by gas chromatography. When the cytotoxicity of the r-CLA and d-CLA samples obtained under 10 mmHg-$220^{\circ}C$ conditions were compared against human breast cancer cells (MCF-7), human lung cancer cells (A-549), human colon cancer cells (HT-29), human prostate cancer cells (PC-3), and human neuroblastoma cells (SK-N-SH), no significant cytotoxicity was seen in the cell lines. These results suggest that the color or colorant in the CLA samples did not have any effects on the proliferation of human cancer and normal cells and imply that the colorant in commercially available CLA samples is safe for human consumption.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.301-305
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• 2012

This study was conducted to investigate the microbiological contamination levels in rice cakes and rice flour due to climate change in three areas classified to their temperature and precipitation. We investigated the contamination levels of total aerobic bacteria, coliforms, Escherichia coli, Bacillus cereus, Staphylococcus aureus, Clostridium perfringens of rice flour and 3 rice cakes such as Garaetteok, Sirutteok and Gyeongdan. Contamination levels of total aerobic bacteria in rice flour were 4.9 log CFU/g. In a total of 70 rice flour, yeasts & molds and coliforms were detected in 42 and 52 samples at the levels of 43 CFU/g and 1.29 log CFU/g, respectively. S. aureus were detected in only 1 rice flour (1.66 log CFU/g) out of 70. In an investigation of contamination levels in rice cakes, the population of total aerobic bacteria were highest in Gyeongdan (5.18 log CFU/g) and coliforms were highest in Gareattock (2.93 log CFU/g). There was no detection of E. coli and B. cereus except for only 1 Gareattock (1.20 log CFU/g). There were no differences of contamination levels among the three areas. If constant monitoring of rice cakes and rice flour is conducted on the basis of this study, it is expected to be able to analyze the change of contamination levels in rice cakes and rice flour due to climate change.

• The Korean Journal of Malacology
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• v.32 no.4
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• pp.263-268
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• 2016

Metallothionein (MT) family of metal-binding proteins are involved in maintaining homeostasis and heavy metal poisoning. Recently, MT has been considered as a biomarker that can identify a particular species, very similar to the use of cytochrome oxidase I (COI) gene. Satsuma myomphala species of land snails have been reported from North-East Asia, including South Korea and Japan. In particular, the land snail species have been known from only a limited area of Geoje Island, Gyeongsangnam-do province of South Korea. Genetic studies of S. myomphala has been limited with only 6 nucleotide, 2 protein registered on the NCBI server. For elucidating the genetic information of S. myomphala, we conducted RNA sequencing analysis using Illumina HiSeq 2500 next-generation platform. We screened the MT gene from the RNA-Seq database to confirm the molecular phylogenetic relationship. After sequencing, the de novo analysis and clustering generated 103,774 unigenes. After annotation against PANM database using BLAST program, we obtained MT sequence of 74 amino acid residues containing the coding region of 222 bp. Based on this sequence, we found about 53 sequences using the BLAST program in NCBI nr database. Using ClustalX alignment, Maximum-Likehood Tree of MEGA program, we confirmed the molecular phylogenetic relationships that showed similarity with mollusks such as Helix pomatia and H. aspersa, Megathura crenulata.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.4
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• pp.605-616
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• 2004

Subinhibitory concentrations (sub-MICs) refer to concentrations below minimum inhibitory concentrations (MICs). The antimicrobial agents may be present at relatively high concentration, at least higher than bacterial MIC and thereafter be deserted off a surface and function at sub-MICs, perhaps by interfering with bacterial metabolism. Consequently, the aim of this study was to determine the effects of growth, in the presence of sub-MICs of antimicrobial agents, on the cell surface properties and virulence factors of mutans streptococci and to investigate the efficacy of a chemical approach in vitro. Streptococcus mutans Ingbritt and Streptococcus sobrinus 6715-7 were used. Eight antimicrobial agents (Sanguinaria extract;SG, Chlorhexidine digluconate;CHX, Fluoride;F, Propolis;PP, Hydrogen peroxide;HP, Triclosan;TC, Sodium dodecyl sulfate;SDS Cetylpyridinium chloride; CC) were diluted serially in broth to determine MICs and to compare the growth rate, acid production, hydrophobicity, adhesion activity to saliva coated hydroxyapatite, glucan synthesis and cellular aggregation of experiment groups (in the presence of sub-MICs) with those of control (in the absence of antimicrobial agents). Sub-MICs of antimicrobial agents affected the growth of cells, hydrophobicity, and adhesion of bacteria to saliva coated hydroxyapatite and glucan synthesis. They also resulted in a significant reduction in pH after 12 hours (p<0.05). By cells pretreated with proteinase K, either the aggregation induced by antimicrobial agents was completely inhibited or the aggregation titers were markedly increased. According to the results of the present study, each antimicrobial agent at sub-MICs could affect similar as its known action mechanism and could continually inhibit cariogenic bacteria at such concentrations. Thus, the use of these antimicrobial agents would be one of the effective methods to prevent dental caries.

• Journal of Food Hygiene and Safety
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• v.37 no.2
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• pp.39-45
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• 2022

This study aimed to investigate the validation and modify the analytical method to determine quercetin-3-𝑜-gentiobioside and isoquercitrin in Abelmoschus esculentus L. Moench for the standardization of ingredients in development of functional health products. The analytical method was validated based on the ICH (International Conference for Harmonization) guidelines to verify the reliability and validity there of on the specificity, linearity, accuracy, precision, detection limit and quantification limit. For the HPLC analysis method, the peak retention time of the index component of the standard solution and the peak retention time of the index component of A. esculentus L. Moench powder sample were consistent with the spectra thereof, confirming the specificity. The calibration curves of quercetin-3-𝑜-gentiobioside and isoquercitrin showed a linearity with a near-one correlation coefficient (0.9999 and 0.9999), indicating the high suitability thereof for the analysis. A. esculentus L. Moench powder sample of a known concentration were prepared with low, medium, and high concentrations of standard substances and were calculated for the precision and accuracy. The precision of quercetin-3-𝑜-gentiobioside and isoquercitrin was confirmed for intra-day and daily. As a result, the intra-day precision was found to be 0.50-1.48% and 0.77-2.87%, and the daily precision to be 0.07-3.37% and 0.58-1.37%, implying an excellent precision at level below 5%. As a result of accuracy measurement, the intra-day accuracy of quercetin-3-𝑜-gentiobioside and isoquercitrin was found to be 104.87-109.64% and the daily accuracy thereof was found to be 106.85-109.06%, reflecting high level of accuracy. The detection limits of quercetin-3-𝑜-gentiobioside and isoquercitrin were 0.24 ㎍/mL and 0.16 ㎍/mL, respectively, whereas the quantitation limits were 0.71 ㎍/mL and 0.49 ㎍/mL, confirming that detection was valid at the low concentrations as well. From the analysis, the established analytical method was proven to be excellent with high level of results from the verification on the specificity, linearity, precision, accuracy, detection limit and quantitation limit thereof. In addition, as a result of analyzing the content of A. esculentus L. Moench powder samples using a validated analytical method, quercetin-3-𝑜-gentiobioside was analyzed to contain 1.49±0.01 mg/dry weight g, while isoquercitrin contained 1.39±0.01 mg/dry weight g. The study was conducted to verify that the simultaneous analysis on quercetin-3-𝑜-gentiobioside and isoquercitrin, the indicators of A. esculentus L. Moench, is a scientifically reliable and suitable analytical method.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.4
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• pp.24-36
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• 2014

The result of the research conducted for the purpose of investigating the semantic value and the layout of the Cheongryu Gugok of Dorimsa Valley, which exhibits a high level of completeness and scenic preservation value among the three gugoks distributed in the area around Mt. Dongak of Gogseong is as follows.4) The area around Cheongryu Gugok shows a case where the gugok culture, which has been enjoyed as a model of the Neo-Confucianism culture and bedrock scenery, such as waterfall, riverside, pond, and flatland, following the beautiful valley, has been actually substituted, and is an outstanding scenery site as stated in a local map of Gokseong-hyeon in 1872 as "Samnam Jeil Amban Gyeryu Cheongryu-dong(三南第一巖盤溪流 淸流洞: Cheongryu-dong, the best rock mooring in the Samnam area)." Cheongryu Gugok, which is differentiated through the seasonal scenery and epigrams established on both land route and waterway, was probably established by the lead of Sun-tae Jeong(丁舜泰, ?~1916) and Byeong-sun Cho(曺秉順, 1876~1921) before 1916 during the Japanese colonization period. However, based on the fact that a number of Janggugiso of ancient sages, such as political activists, Buddhist leaders, and Neo-Confucian scholars, have been established, it is presumed to have been utilized as a hermit site and scenery site visited by masters from long ago. Cheongryu Gugok, which is formed on the rock floor of the bed rock of Dorimsa Valley, is formed in a total length of 1.2km and average gok(曲) length of 149m on a mountain type stream, which appears to be shorter compared to other gugoks in Korea. The rock writings of the three gugoks in Mt. Dongak, such as Cheongryu Gugok, which was the only one verified in the Jeonnam area, total 165 in number, which is determined to be the assembly place for the highest number of rock writings in the nation. In particular, a result of analyzing the rock writings in Cheongryu Gugok totaling 112 places showed 49pieces(43.8%) with the meaning of 'moral training' in epigram, 21pieces (18.8%) of human life, 16pieces(14.2%) of seasonal scenery, and 12pieces(10.6%) of Janggugiso such as Jangguchur, and the ratio occupied by poem verses appeared to be six cases(3.6%). Sweyeonmun(鎖烟門), which was the first gok of land route, and Jesiinganbyeolyucheon(除是人間別有天) which was the ninth gok of the waterway, corresponds to the Hongdanyeonse(虹斷烟鎖) of the first gok and Jesiinganbyeolyucheon of the ninth gok established in Jaecheon, Chungbuk by Se-hwa Park(朴世和, 1834~1910), which is inferred to be the name of Gugok having the same origin. In addition, the Daeeunbyeong(大隱屛) of the sixth gok. of land route corresponds to the Chu Hsi's Wuyi-Gugok of the seventh gok, which is acknowledged as the basis for Gugok Wollim, and the rock writings and stonework of 'Amseojae(巖棲齋)' and 'Pogyeongjae(抱經齋)' between the seventh gok and eighth gok is a trace comparable with Wuyi Jeongsa(武夷精舍) placed below Wuyi Gugok Eunbyeon-bong, which is understood to be the activity base of Cheongryu-dong of the Giho Sarim(畿湖士林). The rock writings in the Mt. Dongak area, including famous sayings by masters such as Sunsaeuhje(鮮史御帝, Emperor Gojong), Bogahyowoo(保家孝友, Emperor Gojong), Manchunmungywol(萬川明月, King Joengjo), Biryeobudong(非禮不動, Chongzhen Emperor of the Ming Dynasty)', Samusa(思無邪, Euijong of the Ming Dynasty), Baksechungpwoong(百世淸風, Chu Hsi), and Chungryususuk-Dongakpungkyung(淸流水石 動樂風景, Heungseon Daewongun) can be said to be a repository of semantic symbolic cultural scenery, instead of only expressing Confucian aesthetics. In addition, Cheongryu Gugok is noticeable with its feature as a cluster of cultural scenery of the three religions of Confucian-Buddhism-Taoism, where the Confucianism value system, Buddhist concept, and Taoist concept co-exists for mind training and cultivation. Cheongryu Gugok has a semantic feature and spatial character as a basis for history and cultural struggle for the Anti-Japan spirit that has been conceived during the process of establishing and utilizing the spirit of the learning, loyalty for the Emperor and expulsion of barbarians, and inspiration of Anti-Japan force, by inheriting the sense of Dotong(道統) of Neo-Confucianism by the Confucian scholar class at the end of the Joseon era that is represented by Ik-hyun Choi(崔益鉉, 1833~1906), Woo Jeon(田愚, 1841~1922), Woo-man Gi(奇宇萬, 1846~1916), Byung-sun Song(宋秉璿, 1836~1905), and Hyeon Hwang(黃玹, 1855~1910).