• Proceedings of the Korean Society of Computer Information Conference
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• 2023.07a
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• pp.237-240
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• 2023

본 논문은 철도 건널목(교차로)에서 발생하는 차량, 보행자 및 야생 동물 사고 등의 상황에서 발생하는 위험 요소를 설정하고 철도 건널목(교차로)의 운행상황을 확인할 수 있도록 모형 철도 주변에 유형별 센서들을 설치하고 데이터를 인지하여 시스템에 저장하고, 유효한 데이터 분석을 통해 Orange3 머신러닝 기법을 적용한다. 철도 건널목에 관련된 이미지 중 위험인자로서 차량, 보행자 및 야생동물등의 객체를 감지하고 데이터를 수집하여 활용한다. 또한 이러한 데이터들은 이용자 상황에 맞는 철도 데이터 운영 시스템으로 적용할 수 있도록 위험 예측 시스템을 제안한다.

• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.2
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• pp.205-216
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• 2023

This study aimed to compare the color stability and surface roughness of three-dimensional (3D) printing resin according to polishing methods. 3D-printed resin specimens were fabricated at TC-80DP (Graphy, Seoul, Korea) with a stereolithography 3D printer, and the specimens were divided into three groups, each of which was not polished, was polished using Enhance^®, and was polished using a Sof-Lex^TM disc. The CIE L^*a^*b^* value and the surface roughness of each group were measured and immersed in artificial saliva and orange juice after 0, 1, 7, 30, and 60 days, and the color difference (ΔE^*) was calculated. As a result of the study, no noticeable color change was observed in artificial saliva, but a noticeable color change was demonstrated in orange juice after 60 days of immersion, and the difference was significant. In the Sof-Lex^TM group, surface roughness according to the solution was found to be significantly higher in the orange juice than that in artificial saliva. No significant difference in color change was found according to the polishing method, but surface roughness was significantly lower in the Sof-Lex^TM group than both that of the unpolished group and that of the Enhance^® group. Nevertheless, all groups exhibited clinically acceptable properties regardless of their higher surface roughness than the threshold for plaque accumulation. Overall, this study recommends utilizing Sof-Lex^TM for polishing 3D printing resin when used in primary anterior tooth coverage.

• Journal of the Korean Chemical Society
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• v.13 no.4
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• pp.313-316
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• 1969

In this paper a simple and rapid method is described for the determination of lead in monazite. A monazite sample was dissolved with hot concentrated sulfuric acid and diluted to 200 ml with distilled water. Lead is quatitatively separated by coprecipitating with strontium. Lead-strontium sulfate is dissolved in 3N NaOH soluion. An excess Zn-EDTA is added. The remaining zinc ion is titrated with standard 0.01 M EDTA solution using xylenol orange as indicator at pH 5 in the presence of KCN and acetyl acetone as masking agents.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.3
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• pp.469-481
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• 2006

Among the etiologic factors of enamel corrosion, daily intake has been considered with a profound interest, especially the intake of acidic drinks. It is thought that the rapid consumption of acidic drinks will not only results in the affection to the teeth but also to the surface of the tooth-colored restorative materials. Therefore, the puopose of this study is to examine the alterations occurred in the surface of the tooth-colored materials according to the exposed time, with 3 most common acidic drinks in contact with daily life. Resin-modified glass-ionomer, polyacid-modified composite resin, composite resin were immersed on 0.9% NaCl, Coke, orange juice, sports beverages as 4 groups in each. The surface hardness and the surface roughness of specimens were measured with following methods: before immersion, 1 day after immersion, 1-,2-,3-,4- weeks after immersion. Results were as follows. 1. Tooth-colored restorative materials, with the exception of composite resin, showed statistically significant changes in surface hardness and roughness when immersed on acidic drinks(p<0.05). 2. The degree of change in surface hardness and roughness occurred as follows, in order of severity from greatest to least resin-modified glass-ionomer, polyacid-modified composite resin, composite resin 3. Sports beverages resulted in greater alterations to surfaces than Coke and orange juice. 4. In the SEM image of the groups immersed in acidic drinks, resin-modified glass-ionomer and polyacid-modified composite resin showed loss of filer. Severe cracks were observed, especially on the resin-modified glass-ionomer.

• Journal of the Korean Society for Library and Information Science
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• v.41 no.2
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• pp.161-180
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• 2007

The goal of this study is to examine what sort of books people read repeatedly, what are the different preferences between men and women, how much the repeatedly-read books are related to the most memorable books and how the repeatedly-read books are connected to reading habits. A questionnaire was provided to college students and their repeated reading experiences were searched. The results of the statistical analysis are summarized : 1) Most college students have experienced repeated reading more than twice. 2) The number of college students who have experienced repeated reading twice is the highest and next, those who have read repeatedly 3 times. Also, the number of times of repeated reading tends to be similar between male and female students. 3) The books which many students read repeatedly more than twice are : a) Romance of 3 Kingdoms b) Little Prince c) Da Vinci Code d) Alchemist e) Chinese nine spine stickle back f) Meu Pe do Larania Lima g) Harry potter. 4) About half of the students have read the most memorable books many times. 5) The importance of books was evaluated on the basis of the number of repeated readers and the number of readings. The order of the important books is Three Romans of 3 kingdoms, Little Prince, Da Vinci Code, Meu Pe do Larania Lima, Tuesdays with Mollie, Harry Potter, and The Myth of Greece and Rome. 6) The preferred books by male college students are mostly the stories of fighters while female likes books that contain deep emotion and morality. More than half of the males' repeated reading was Romance of 3 Kingdoms while the preferred books of females are distributed widely.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.74-79
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• 2002

Three different kinds of the crude vinegars obtained from oak(Quercus serrata), bamboo(Phyllostachys pubescens) and pine(Pinus densiflora) species were stored for approximately one year and periodically analyzed to monitor their physicochemical changes. Small changes in physical properties, such as the pH, specific gravity and amount of organic acids as well as water-soluble tar were observed in the entire course of aging period. However, the color difference of the vinegars showed a remarkable change between 7 and 10 months. In addition, these vinegars' colors changed from light yellowish orange to much deeper purple and orange during this period. The amount of organic acids and neutral compounds(dihydro-2(3H)-furanone, furfural, furfuryl alcohol, 2-hydroxy-1-methyl-1-cyclopenten-3-one, 1-hydroxy-2-propanone and methanol) in the vinegars increased or decreased periodically every three months. A good linear relationship (correlation coefficient of ca. 0.92) was obtained between the amount of organic acids and the amount of neutral compounds in such changes. However, although the amount of phenols increased or decreased periodically, its amount was decreased over the entire aging.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.495-499
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• 1985

To develope a process by which liquid foods can be stored in the liquid state at the frozen storage temperature, suitable cryoprotectants were selected. Orange juice, chosen as an example of liquid foods, was stored with combined cryoprotectants at $-15^{\circ}C$, and quality changes of orange juice during storage were evaluated. Among 7 cryoprotectants tested, NaCl solution had lower initial freezing point than others, and initial freezing points of glucose, fructose, glycerol, propylene glycol and citric acid were close to each other. Considering flavor quality of orange juice, cryoprotectants suitable for reducing freezing point of orange juice were glucose, fructose, glycerol, and citric acid. Combined cryoprotectants for reducing freezing point of 3 and 4 folds concentrated orange juice to $-15^{\circ}C$ consisted of 10% glucose, 8% frutose, 4.6% glycerol and 3% citric acid, and 5.5% glucose, 4.5% fructose, 4.6% glycerol, and 3% cirtric acid, respectively. When destruction of ascorbic acid, sedimentation volume and sensory flavor score of orange juice stored with combined cryoprotectants at $-15^{\circ}C$ and the control stored at $-18^{\circ}C$ were compared, there were no significant differences. These results indicated that liquid foods with suitable combined cryoprotectants could be stored at $-15^{\circ}C$ or below in the liquid state without adverse effect on quality of the stored products.

• Research in Plant Disease
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• v.22 no.4
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• pp.293-296
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• 2016

In late June 2016, stalk rot symptoms were observed on five vatieties of sorghum (Sorghum bicolar) at organic paddy-upland rotation system in Anseong city, Korea. The initial symptom on stalk surfaces was red color with a dark red spot lesion. A fungus was isolated from the initial lesion, and cultured on potato dextrose agar. Size of microconidia mostly extend to $5-19{\times}2-{\mu}m$ in culture, with 0-1 septa and macroconidia extend to $29-52{\times}3-4{\mu}m$ with 4-6 septa. Pathogenicity was investigated using conidial suspension spray to seedling of sorghum. After 3 days of inoculation, the dark red lesion was produced on stalks. On the basis of mycological characteristics, pathogenicity, and internal transcribed spacer (ITS) rDNA sequence analysis, this fungus was identified as Fusarium thapsinum. This is the first report of stalk rot on sorghum caused by F. thapsinum in Korea.

• The Korean Journal of Pesticide Science
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• v.14 no.1
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• pp.21-29
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• 2010

The analytical method for bifenazate was developed using a HPLC (UVD). Also, analytical condition of LC/MS was set up for bifenazate. We validated the method for the precision and the reproducibility. The correlation coefficient of bifenazate ranged from 0.05 to 2.5 mg/kg was 1.0. Limit of quantitation (LOQ) was 0.01 mg/kg. To measure recoveries from agricultural products such as foxtail millet (cereal grains), kidney bean (beans), orange (fruits), perilla leaves (vegetables) and oak mushroom (mushrooms), bifenazate was spiked. Mean recoveries of bifenazate for each sample were 82.7~104.1% at the level of 0.1 mg/kg and 73.1~104.3% at the level of 0.5 mg/kg. The relative standard deviations (n=3) were 0.2~9.7%. Pesticide residues for bifenazate were investigated in 16 commodities (rice, foxtail millet, buckwheat, kidney bean, peanut, sesame, orange, grapefruit, kiwifruit, spinach, perilla leaves, leek, garlic stem, garlic, ginger and oak mushroom) collected from 22 provinces in 2009. Bifenazate was analyzed using analytical method by HPLC from 304 samples, and residue was not detected.

• Korean Journal Plant Pathology
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• v.13 no.2
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• pp.129-131
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• 1997

Occurrence of brown rot was observed on imported orange fruits, and irregular brown spots were appeared as an intial symptom. White colored mycelia were developed rapidly on the surface of the fruits under the humid condition and resulted in rotting of the fruits. The causal organism of brown rot of orange was identified as Phytophthora citrophthora. Most sporangia were nondeciduous, papillate, ovoid, and measured 25.5~51.5$\times$17.9~34.7 ${\mu}{\textrm}{m}$ in size. P. citrophtora was pathogenic on Satsuma mandarin as well as orange. Symptoms were produced 3~7 days after artificial inoculation of sporangia and mycelia mixture on the fruits of orange and Satsuma mandarin, which were similar to those on the naturally infected fruits.