• Korean Chemical Engineering Research
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• v.55 no.4
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• pp.535-541
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• 2017

On the basis of 200 ppm of Ag and 120 l/h of feed flow rate, we built a pilot plant of an ion exchange fiber system having an double tube type ion exchange chamber with strong base ion exchange fiber (FIVAN A-6) which was designed to replace fibers easily and to eliminate the need for a fixture. The following results were obtained for the double tube type of ion exchange fiber system with an ion exchange capacity of 4.6 meq/g for Ag. The adsorption process was operated in the range of 40~90 l/h after confirming the effect of the flow rate and, pH did not affect formation of complex ion of Ag in the range of pH 7~12. In the case of backwash process, the recovery rate of Ag was tested in the range of 60~120 l/h and comparative experiments were carried out using NaOH, $NH_4Cl$, and NaCl as the chemicals for backwash. Although the desorption time was shortened at higher concentration, the desorption efficiency per mol was lowered. Therefore, it was confirmed that the desorption time and the concentration should be well balanced to operate economically. The desorption pattern of the backwash process is slower than the adsorption process and takes a lot of time. The results showed that the Ag adsorption ratio was 99.5% or more and the Ag recovery ratio was 96% or more, and commercialization was possible.

• Korean Journal of Community Nutrition
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• v.15 no.5
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• pp.625-635
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• 2010

The purpose of this study was to define a one portion size of food frequently consumed by Korean children aged 6-11 for convenient use in food selection, diet planning, nutritional evaluation, and nutrition education. We analyzed using the original data on 889 persons (9.96%) aged 6-11 years among 8,930 persons to whom NHANES 2005 and selected food items consumed by the intake frequency of 10 or higher among the 500 most frequently consumed food items. A total of 172 varieties of food items of regular use were selected. Also the portion size of food items was set on the basis of the median (50 percentile) of the portion size for a single intake by a single person was analyzed. The portion size of cereals was 5 g for prosomillet to 120 g for hamburger. As for vegetables, it posted 1 g for red pepper to 50 g for nabakkimchi. The portion size of meats and products was 15 g for luncheon meat to 120 g for beef feet soup. In comparison of children's portion size with adults', the children's portion sizes of every food groups, with the exception of meats and eggs, were lower than those of adults. The portion size of the regular food items of children in this study will be conveniently and effectively used by children, children's diet planners and researchers in selecting food items for a nutritionally balanced diet and in assessing the children's diet intake.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.621-626
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• 2020

The incidence of colorectal cancer (CRC) in Korea has been gradually increased and it has been reported that dietary life is highly associated with the development of CRC. To investigate dietary attitudes and nutritional risk factors for CRC, we analyzed food intake of 34 patients diagnosed with CRC within 1 year and 51 subjects without gastrointestinal diseases as a control reside in Daegu·Gyeongbuk Area using semi-quantitative food frequency questionnaire. The results showed that dietary regularity and variety of food intake in control subjects was better than CRC patients whereas, CRC patients eat more frequently animal and vegetable protein foods, fried foods, green and yellow vegetables, and fruits than control subjects. Nutrient intake analysis showed that Vitamin A, E, K, C, sodium, magnesium, iodine, and cholesterol intake of CRC patients was higher than control subjects. Especially, after adjusting age and sex, regression analysis showed that Vitamin K (OR = 1.022, 95% Cl 1.003-1.043, p = 0.026) and sodium (OR = 1.001, 95% Cl 1.000-1.002, p = 0.032) were identified as risk factors for CRC. In the future, verification of the relationship between these nutrients and CRC risk and appropriate nutrient education will be needed for the prevention of CRC.

• Korean Journal of Construction Engineering and Management
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• v.15 no.4
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• pp.86-94
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• 2014

Since the late 1990s, mixed-use apartment, armed with high qualities and large scales with a high ratio of TFA(Total Floor Area) have been continuously provided accommodating exclusive community facilities along with high-tech securities, not to mention excellent skyline view. However, especially in mid-small cities, there have been only a few supplies. As a result, none of the mixed-use housing provided by high-end brands has ever been built in non-metropolitan area. But constructors couldn't plan the projects which aims to build the mixed-use apartment in local city, because they couldn't get the basic data or advanced research for feasibility analysis. Therefore, to suggest the useful price for mixed-use apartment supply project of local city, the PSM(Price Sensitivity Method) widely used for determining the price preferences as a market research tools has been applied. As analysis results, the estimated price of mixed-use apartment is 10.8% higher than general apartment, and mixed-use apartment has lower price sensitivity than general apartment. As price determinants, the age, education level and family size influence on UTP in significant level. It is expected that these research findings can be applied for establishing the solid marketing strategy of mixed-use apartment development project in local city.

• Korean Journal of Social Welfare Studies
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• v.49 no.2
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• pp.93-124
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• 2018

Using the Korean Survey of Household Finances and Living Conditions panel data from 2012~2016, this study analyzed youth (19~34 years) poverty and employment and examined the factors that affect employment status. The analysis revealed an increase in the proportion of young people who are students or jobless; the economic conditions of the young people varied by factors such as marital status, education, job status, and loans; and the government public transfer policy had little impact on reducing the relative poverty rate of the youth. We also examined the factors affecting the youth's employment status and the risk of being employed in low-paid jobs, using multi-logit and logit regression model respectively. Considering employment status, the older and more educated the youth were, the less frequently they were employed in temporary or daily jobs instead of regular ones, but there was no difference between genders in terms of having temporary or daily jobs. A logit analysis on the determinants of low-paid jobs demonstrated that women, the less educated, spouses or children of the household, and temporary or daily workers have a greater probability of working at low-paid jobs. As women became older, their risk of having low-paid jobs increased, which demonstrated the phenomenon of "lock-in" at low-paid jobs. Temporary or daily workers of all age groups faced a higher risk of lowpaid employment, which stood out for the youth. Based on these results, we suggest that government employment and welfare policies should consider individual characteristics of the youth and their life cycle, along with efforts to supply decent jobs, continuously and stably.

• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.1
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• pp.47-64
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• 2023

In this study, the recognition of child abuse and neglect (CAN) and reporting attitudes of general dentists and pediatric dentists in Korea were estimated. A survey was conducted among dentists working at clinics or university hospitals, including interns and residents at dental hospital training institutions. The questionnaire, consisting of 32 questions and detailed questions, subdivided into 'general characteristics of respondents', 'CAN', 'CAN report', 'laws to CAN', 'countermeasures against CAN'. The survey was conducted using a messenger, and 176 respondents' answers were analyzed. The recognition of CAN showed high scores in the order of physical abuse, neglect, and emotional abuse. The positive attitude toward reporting CAN had a higher score than the negative attitude. Of the total respondents, 19 said they reported child abuse, and 18 said they were suspected of child abuse but hesitated to report it. Among the laws related to CAN, the protection measures for CAN reporters and the protocol for CAN showed low awareness. Since then, they have wanted to know how to find abused children and how to deal with them in education. This study is expected to be used as data to improve dentists' awareness and consciousness of CAN in the future.

• Journal of Digital Convergence
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• v.20 no.1
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• pp.33-39
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• 2022

This study aims to investigate the online class preference depending on students' gender and school level. To achieve this aim, the study conducted a survey on 4,803 elementary, middle, and high school students in 17 regions nationwide. The valid data of 4,524 were then analyzed using the Apriori algorithm to discern the associated patterns of the online class preference corresponding to their gender and school level. As a result, a total of 16 rules, including 7 from elementary school students, 4 from middle school students, and 5 from high school students were derived. To be specific, elementary school male students preferred software-based classes whereas elementary female students preferred maker-based classes. In the case of middle school, both male and female students preferred virtual experience-based classes. On the other hand, high school students had a higher preference for subject-specific lecture-based classes. The study findings can serve as empirical evidence for explaining the needs of online classes perceived by K-12 students. In addition, this study can be used as basic research to present and suggest areas of improvement for diversifying online classes. Future studies can further conduct in-depth analysis on the development of various online class activities and models, the design of online class platforms, and the female students' career motivation in the field of science and technology.

• Korean Journal of Community Nutrition
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• v.28 no.6
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• pp.466-479
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• 2023

Objectives: A mobile health intervention program was provided for employees with overweight and obesity for 12 weeks, and a process evaluation was completed at the end of the program. We investigated participant engagement based on app usage data, and whether engagement was associated with the degree of satisfaction with the program. Methods: The program involved the use of a dietary coaching app and a wearable device for monitoring physical activity and body composition. A total of 235 employees participated in the program. App usage data were collected from a mobile platform, and a questionnaire survey on process evaluation and needs assessment was conducted during the post-test. Results: The engagement level of the participants decreased over time. Participants in their 40s, high school graduates or lower education, and manufacturing workers showed higher engagement than other age groups, college graduates, and office workers, respectively. The overall satisfaction score was 3.6 out of 5. When participants were categorized into three groups according to their engagement level, the upper group was more satisfied than the lower group. A total of 71.5% of participants answered that they wanted to rejoin or recommend the program, and 71.9% answered that the program was helpful in improving their dietary habits. The most helpful components in the program were diet records and a 1:1 chat with the dietary coach from the dietary coaching app. The barriers to improving dietary habits included company dinners, special occasions, lack of time, and eating out. The workplace dietary management programs were recognized as necessary with a need score of 3.9 out of 5. Conclusions: Participants were generally satisfied with the mobile health intervention program, particularly highly engaged participants. Feedback from a dietary coach was an important factor in increasing satisfaction.

• Korean journal of food and cookery science
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• v.21 no.3 s.87
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• pp.290-300
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• 2005

Increased sanitation management of foodservice establishments is required because most of the reported foodborne-disease outbreaks were in the foodservice industry. The purpose of this study was to determine the important control points for good sanitation. In this study, we inspected twenty foodservice establishments in Seoul, Kyunggi, Kyungnam with a self-developed monitoring tool. These foodservice establishments included secondary schools, universities, and industries. Six of them had appointed as the HACCP-certified establishments from the Korea Food and Drug Administration. The inspection was conducted from June to August in 2002. The inspection tool consisted of nine dimensions and sixty-five items. The dimensions were 'personal sanitation', 'supply of raw food', 'food storage', 'handling of raw food and ready-to-eat', 'cleaning and sterilization', 'waste control', 'pest control', and 'control of establishment and equipment' The highest possible score of this inspection tool is 105 points. Statistical data analysis was completed using the SPSS Package(11.0) for descriptive analysis Kruskal-Wallis. The score for the secondary schools (83.6 points) was higher than for the others and number of in compliance item was 50.9 on average. Therefore, we concluded that the secondary schools' sanitation condition was good. The foodservice establishments acquired HACCP certification was 89.7 points, which was significantly higher than that of establishments not applying foodservices in total score. Instituting the HACCP system in a foodservice is very effective for sanitation management. Many out of the compliance observations were found in the dimensions of 'waste control', 'control of establishment and equipment', and 'supply of raw food' 'Clean condition of refrigerator' item was $65\%$ out of the compliance that was the highest percent in this study. 'Notify and observance of heating/reheating temperature' was $45\%$ out of compliance. Items which were over $30\%$ out of compliance were 'sterilization of knifes and chopping boards in cooking', 'education of workers', 'maintain refrigerator temperature blow $5^{\circ}C$', and 'countermeasure of infection workers' In the results, most of the foodservice establishments were poorly managed in temperature control and cross-contamination. The important control points revealed in this study were preventing contamination, cooking temperature compliance, management of raw food and refrigerator. Therefore foodservice establishments should pay attention to education and training about important control points. The systematic sanitation management monitoring tool developed in this study can be effectively applied for conducting self-inspection and improving the sanitary conditions of their own foodservice operations.

• Journal of agricultural medicine and community health
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• v.12 no.1
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• pp.80-93
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• 1987

Mass chemotherapy of Clonorchis sinensis infection in Korea was started in 1982 with 40mg/kg body weight single dose administration scheme of praziquantel. The purpose of this study was to investigate the efficiency of current mass chemotherapy project and compare the epidemiological changes in endemic area of Ckmorchis sinensis. This study was performed at Kimhae-city and Samrangjin-eup of Miryang-gun, Kyongnam province, highly endemic area of C. sinensis located southeastern part of Korea from July to October of 1986. The therapy project of Kimhae area was performed in 1984, whereas that of Samrangjin was done in 1985 by stool examination of the Korea Association for Parasite Eradication(KAPE) and drug administration of local health centre. The results obtained were as follows; 1) As a results of stool examination from 234 specimens obtained in Kimhae area, the infection rate has decreased to 34.2%from 45.6p in 1983, but the infection rate of C. sinensis from 341 specimens obtained in Samrangjin area did not decrease (58.1%in 1986 490%in 1983). 2) The study in Kimhae area showed that the average EPG decreased remarkably from 4,858 to 1,340 and those classified above the category of heavy infection decreased also from 14.0pp to 1.7%. The study in Samrangjin area showed that the average EPG did decrease drastically from 9,597 to 6,498 and those classified above the category of heavy infection did not go down drastically from 25.2% to 14.2%. 3) The study in Kimhae area showed decrease of Cs.$D._{50}$ in comparison to that in 1983, wheareas Cs.$D._{50}$ in Samrangjin area showed no much difference compared to that in 1983. The intensities of endemicity were represented with the regression equation calculated with the cumulative percentages of EPG count. Regression equation was Y=4.49+1.19 log x in Kimhae area and Y=3.66+127 log x in Samrangjin area. 4) The two stage catalytic model was applied and the calculation lead to the equation $Y=5.33(e^{-0.018t}-e^{-0.016t})$ in Kimhae area and $Y=1.25(e^{-0.010t}-e^{-0.018t})$ in Kimhae area and $Y=125(e^{-0.010t}-e^{-0.050t})$ in Samrangjin area 5) The infection rate of cercaria in P.manchouric-us studied in Kimhae area showed 1.25% which is not much different from that in previous years, wheareas the infection rate of metacercaria in P. parva studied in the same area this year showed 2.5-20.2/gm of flesh in comparison to 64/gm of flesh in 1983. 6) Data of C. sinensis infection on the reservoir host in Kimhae area showed 4 out of 18 dogs, 1 out of 18 rats and that in Samrangjin area showed 2 out of 18 dogs respectively. 7) Among the inhabitants who were under mass chemotherapy in Kimhae area, 71out of them, upon stool examination, showed infection rate of 66.2% and those classified above the category of heavy infection, 2.4%. In comparison to infection rate of 33.7% and those classified above the category of heavy infection, which is 1.0%, obtained from those not under mass chemotherapy showed higher infection rate and somewhat equal distribution of intensity of infection. The above statements reflect the fact that individual therapy besides mass chemotherapy was prevalent in that area. 8) On the other side, the studies in Samrangjin area showed infection rate of 68.7% and those above the category of heavy infection, which is 6.1%, in comparison to infection rate of 58.3% and those above the category of heavy infection, which is 16.5%, in those not under mass chemotherapy. the above reflects that although a good deal of inhabit-ants were classified under light or moderate infection category, those above the category of heavy infection, yet, numbered a lot, and individual chemotherapy has not been going on. In conclusion, it was suggested that the number of reinfected inhabitants among those under mass chemotherapy were numerous. Accordingly, the reinforcement of health education should be followed with mass chemotherapy. The facts of high infection rate exemplified by 65% and high number of those above the category of heavy infection in Samrangjin area say that reevaluation of dosage, number of medication and intervals should be necessarily made.