• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.3
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• pp.254-263
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• 2006

Manganese has a role as both toxic and essential in humans. Manganese is also an essential component in the welding because it increases the hardness and strength, prevents steel from cracking of welding part and acts as a deoxidizing agent to form a stable weld. In this study, manganese generation rate and its content was determined in flux cored arc welding on stainless steel. Domestic two products and foreign four products of flux cored wires were tested in the well designed fume generation chamber as a function of input power. Welding fume was measured by gravimetric method and metal manganese was determined by inductively coupled plasma-atomic emission spectrophotometer. The outer shell of the flux cored wire tube and inner flux were analyzed by scanning electron microscopy to determine their metal compositions. Manganese generation rate($FGR_{mn}$) was increased as the input power increased. It was 16.3 mg/min at the low input power, 38.1 mg/min at the optimal input power, and up to 55.4 mg/min at the high input power. This means that $FGR_{mn}$ is increased at the work place if welder raise the current and/or voltage for the high productivity. The slope coefficient of $FGR_{mn}$ was smaller than that of the generation rate of total fume(FGR). Also, the correlation coefficient of $FGR_{mn}$ was 0.65 whereas that of FGR is 0.91. $FGR_{mn}$ was equal or higher in the domestic products than that of the foreign products although FGR was similar. From the electron microscopic analytical data, we concluded that outer shell of the wire was composed mainly of iron, chromium, nickel and less than 1.2 % of manganese. There are many metal ingredients such as iron, silica, manganese, zirconium, titanium, nickel, potassium, and aluminum in the inner flux but they were not homogeneous. It was found that both $FGR_{mn}$ and content of manganese was higher and more varied in domestic flux cored wires than those of foreign products. To reduce worker exposure to fumes and hazardous component at the source, further research is needed to develop new welding filler materials that improve the quality of flux cored wire in respect to these points. Welder should keep in mind that the FGR, $FGR_{mn}$ and probably the generation rate of other hazardous metals were increased as the input power increase for the high productivity.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.1
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• pp.23-36
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• 2011

The purpose of this study is to make theoretical examinations into the makeup trend shown in digital communication environment and thereby determine potential associations of makeup trend with digital communication environment and characterize said trend, so that it can provide reference materials required for follow-up studies. This study comes to the following findings: First, it is found that there are sociocultural characteristics of digital communication environment, such as interactivity, technology-orientedness, sentiment-orientedness and mixture of time and space. Secondly, it is found that trends developed in makeup fall categorically into interactivity, virtuality, amusement and mobility. Thirdly, it is found that each type of digital communication adopts a mixture and juxtaposition of contemporary styles or categories with traditional ones through eclectic combination based on open-minded and horizontal ideas. Fourthly, it is found that a trend from digital communication environment doesn't coincide perfectly with any makeup trend, but the former trend works interactively and organically with the latter trend on the basis of homogeneity and similarity within a general framework that represents external esthetics of human being. With the creation of digital communication environment, our contemporary society forms as the complex phenomena of digital society in a combination and destruction of different categories beyond any certain international boundary, so that a hybrid tendency appears in contemporary makeup trend as well. Based on these findings, this study has its implications in the sense that it gives a new viewpoint based on design, formative characteristics and expression styles of makeup, and also provides useful reference materials for related industrial sectors.

• Journal of Food Hygiene and Safety
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• v.15 no.2
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• pp.68-78
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• 2000

In Korea, food balance sheet and national nutrition survey have been conducted in parallel by Central Government for several decades. However, the gap between the two statistics became larger to reach an intolerable level in recent years, likely due to the limitation of dietary survey method in spite of the drastic change in dietary habits after industrialization and urbanization during last three decades. The currently available data from national nutrition survey was optimized by taking in to account of the food balance sheet. Adjusted consumption data for individual food items during the period of 1991-95 were given in tabular forms for groups of cereals potatoes sugars & sweets, legumes, nuts & seeds, fruits, vegetables, meats, eggs, dairy products oils & fats and fishery foods. Conversion factors of processed foods including wheat products, soybean products, Kimchi and dairy products into their raw materials were tentatively proposed. Great differences between supply data and intake data of food commodities were pointed out to be likely due to the seasonal variation and ignorance of processed foods and dining-out in the national nutrition survey. It is recommended to utilize these optimized food intake data as the nationally-representative one until new data from the national health and nutrition survey undertaken after modified procedures since 1998 are obtained and verified in future.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.191-197
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• 2018

With a population of more than 10 million people worldwide, MegaCity was only three in 1975, but it is expected to grow to 24 in 2013 and more than 30 in 2025 and more than 3 billion worldwide by 2050 It is expected to be absorbed into smart city. Especially in Asia and Africa, urbanization is expected to proceed rapidly. As the urbanization progresses and the population living in the cities increases, there are various problems such as rapid increase of energy consumption, congestion of traffic, various aging of the infrastructure and the like. As a result, smart city is emerging as a new alternative for solving urban problems. Smart City is rapidly expanding with the development of related technologies and can improve costs, improve urban services, improve quality of life, productivity and sustainability. Therefore, this paper analyzes the size and trend of the domestic and overseas smart city market, and analyzes the smart city related policies, trends and case studies of major countries to see the development status and market of smart city related industries, Present a business utilization model.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.360-366
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• 2014

Kimchi is a Korean traditional fermented food with various health functionalities. However, the protective effects of kimchi against Alzheimer's disease (AD) have not been studied yet. In this study, the protective activities of kimchi extract against oxidative stress and AD were investigated in an amyloid beta ($A{\beta}$)-induced AD model using ICR mice. Kimchi extract exerted strong scavenging activities against 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radical. In addition, T-maze, object cognition, and water maze tests were carried out using the AD model. The $A{\beta}_{25-35}$-injected groups showed impairment of cognition and memory. However, the abilities of novel object recognition and new route awareness were improved by administration of kimchi extract (100 and 200 mg/kg/day) for 2 weeks. Furthermore, the results on water maze test indicated that kimchi extract exerted protective activity against cognitive impairment induced by $A{\beta}_{25-35}$. The present study suggested that kimchi protected against $A{\beta}$-induced impairment of memory and cognition as well as attenuated oxidative stress.

• Journal of radiological science and technology
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• v.40 no.3
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• pp.453-460
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• 2017

This study proposes effective quality control and maintenance method by developing a new qualitative evaluation method of apron for medical radiation protection. As an experimental material, one of 0.45 mm lead and 100 of 0.45 mm Pb aprons were used and irradiated under the conditions of a tube voltage of 75 kVp and a tube current of 12.5 mAs to obtain an image. and using the Image J program, PSNR values were compared and analyzed. The results showed that there were 40 aprons (less than 11dB), 55 aprons (less than 11dB, less than 30dB), and 5 aprons (30dB or more). In addition, the dose showed a normal distribution for the apron, and 5 aprons with PSNR less than 11dB and 30dB or more were selected and divided into 8 zones, and these groups were statistically significant.

• Journal of the Korean Society of Radiology
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• v.12 no.2
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• pp.225-231
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• 2018

Recently, new teaching methods for communicating with teachers and students have been emerged according to the trends of decreasing the school-age population and the development of the mass media. We have applied teaching-learning model based on the flip learning to the college students in this work. As a result of the test for the customized flipped learning teaching-learning model in pre-class, the attendance rate of the major subject was 92.3% whereas that in liberal arts courses other than majors revealed 87.6%. This result for attendance rate shows that first year students in the radiology department have been actively participated in pre-class of the major subject than that of the liberal arts curriculum. From comparing the differences between the study group that was applied flipped learning in class and the non-applied group, the research group showed higher scores in knowledge, skills, and attitudes than the comparative group. In addition, more than 90% of the learners improved their responsibility, problem solving ability, creative thinking, cooperative ability, and communication ability through this learning program. From the test for the difference in the role of radiologists in the post class, the mean score was 4.40 for the group applied the teaching-learning model while that for non-applied group was 2.10. Hence, from such results, we see that this teaching-learning model is appropriate and needs to be extended to cultivate basic skills in radiology and relevant vocational education.

• The Korean Journal of Food And Nutrition
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• v.18 no.3
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• pp.241-253
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• 2005

This study was carried out to investigate the relationship between demographic characteristics and conscious behavior of 287 workers. The results of the study are as follows: The participants of the study were composed of 139 males $(48.4\%)$ and 148 females $(51.6\%)$. 75 workers are 25 years old or younger $(26.1\%)$. Regarding the frequency of eating out, 211 workers $(73.6\%)$ answered that they had eating out ever once a week. Males ate out more frequently than females (p<0.001). The motives for eating out was mostly for meals. This response was more frequent for female than male. To the contrary, more males answered that they ate out for the purpose of social intercourse. As the level of average monthly income increases, the purpose of eating out changed from the purpose of meals to the purpose of social intercourse (p<0.001). For cost of eating out, the older workers and those who had higher monthly income spent significantly more expenditure. However gender difference didn't make any significant difference in the eating out expenses per person. The average monthly eating out expenses were significantly higher for female than male, for the order workers than the younger, for the married than the single, and for those who have higher monthly income than lower. However, the expenses were not significantly different in occupation. Regarding the types of restaurants that the workers preferred for eating out, the most workers preferred Korean restaurant. The types of restaurants that workers preferred significantly related to all the demographic characteristics (p<0.01). In general, participants had eating out with their family. However, younger, single, and low income workers seemed to more eat out with their friends. The most preferred menu was pork dishes. Male rather than female, the married rather than the single, and those who have a professional occupation appeared to like it more. It is necessary to research the major customers' demographic characteristics and their preferences, and then to develop new goods which fit to the customers before entering the restaurant business. It may be concluded that it should be important to develop nutritious, safe, and delicious foods.

• Korean Journal of Environmental Biology
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• v.24 no.1 s.61
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• pp.38-45
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• 2006

Ecological characteristics of microbial populations inhabiting heavy metal polluted soil were investigated. The samples were collected from 293 sites around an factory and industry at Gyeoungsangbuk-do. We measured the contents of seven heavy metal elements (Cd, Cu, As, Hg, Pb, $Cr^{6+}$, CN), seven sites have been seriously contaminated by mercury and chrome. A quantitative evaluation of microbial populations in mercury and chrome contaminated soil was examined by using plate count method. Bacterial numbers in polluted soil samples ranged from $7.4X10^5\;to\;9.3X10^7\;cfu\;g^{-1}$, about $10\sim100$ fold less than the count for the unpolluted soil. Moulds were not detected in chrome polluted soil. The log values of actinomycetes of each contaminated soil samples were log ranged from 6.18 to 7.52. The ratio of actinomycetes was similar to unpolluted soil. The investigation showed actinomycetes to be the major microbial population inhabiting the mercury and chrome polluted soil. Thirty-one isolates among the total isolates were examined for antibacterial activity. These isolates were identified based on a phylogenetic analysis using 16S rRNA gene nucleotide sequences, they were categorized in three major phylogenetic groups, belong to the Streptomyces (6 strains), Saccharopolyspora (3 strains), Nocardiodes (1 strain). On the phylogenetic tree, the clade consisting of five isolates were distantly related to all of the established Streptomycetes genera, indicating the possibility as members of new species.

• Science of Emotion and Sensibility
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• v.19 no.4
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• pp.41-54
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• 2016

Recently, in the arena of online shopping, the gap between offline channel and online channel tends to be narrowed significantly. Though previous studies also represent this trend, it still remains ambiguous how much offline trust has a significant influence on user's online shopping behaviors. Furthermore, those research issues such as how individual neuroticism, uncertainty, and transaction cost plays an important role in explaining user's online shopping satisfaction and continuance intention. In this sense, this study aims to organize a new research model including offline trust, uncertainty, transaction cost, satisfaction, and continuance intention. Especially, we are interested in investigating how much moderating effects the individual neuroticism possesses for the paths among the rest of constructs. By using 406 valid questionnaires, we found empirically that transaction cost affects user's online shopping continuance intention, but it has no influence on satisfaction. The individual neuroticism has full moderating effects on the paths on the rest of constructs included in the proposed research model.