• Journal of the Korean Society of Safety
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• v.37 no.4
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• pp.120-128
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• 2022

Printed circuit boards (PCBs) are a basic component in the electronics industry and are widely used in nearly all electronic products, such as mobile phones, tablet computers, and digital cameras, as well as in electric equipment. PCB manufacturing involves the use of many chemicals and chemical processes and therefore has more risks than other manufacturing sectors. This study aims to identify the causes of possible accidents during PCB manufacturing through risk assessment, develop and implement safety measures, and evaluate the effectiveness of these measures. Note that the safety measures developed to mitigate the risks of a certain process were also implemented for other similar processes. The risk assessments conducted over seven years, from 2015 to 2021, at a PCB manufacturing company identified 361 hazardous processes. Between 2016 and 2019, 41-56 hazardous processes were identified per year; such processes decreased to fewer than 20 per year after 2020. Application of the risk assessment results to the improvement of the hazardous processes with the similar characteristics seems to be effective in decreasing the risks. Equipment-related factors such as lack of appropriate maintenance, low work standards, and defective protection devices were responsible for 59.8% of all possible accidents. Because PCB manufacturing involves many chemicals, skin contact with hazardous substances, electric shock, fire, and explosion were the most common types of possible accidents (81.7%). In total, 505 safety measures were implemented, including 157 related to purchase and improvement of equipment and devices for safety (31.1%), 147 related to the installation/modification of fire prevention facilities (29.1%), and 69 related to the use of standard electrical appliances (13.7%). Risk assessment conducted after implementing the safety measures showed that these measures significantly decreased risk; 247 processes (68.4%) had a risk level of 3, corresponding to "very low," and 114 processes (31.6%) showed a risk level of 4, corresponding to "low." In particular, risk assessment of 104 processes with risk scores of 12 and 10 other processes with risk score of 16 showed that the risk decreased to 4 after implementing the safety measures. Thus, implementing these measures in similar manufacturing sectors that involve chemical processes can mitigate risk.

• Korean Journal of Psychosomatic Medicine
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• v.26 no.2
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• pp.77-85
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• 2018

Objectives : This study aimed to investigate the level of distress using the distress thermometer (DT) and the factors associated with distress in postoperative breast cancer (BC) patients. Methods : DT and WHOQOL-BREF (World Health Organization Quality of Life Scale Abbreviated Version) along with sociodemographic variables were assessed in patients undergoing surgery for their first treatment of BC within one week postoperatively. The distress group consisted of participants with a DT score ${\geq}4$. The prevalence and associative factors of distress were examined by descriptive, univariable, and logistic regression analysis. Results : Three hundred seven women were recruited, and 264 subjects were finally analyzed. A total of 173 (65.5%) were classified into the distress group. The distress group showed significantly younger age (p=0.045), living without a spouse (p=0.032), and worse quality of life (QOL) as measured by overall QOL (p=0.009), general health (p=0.005), physical health domain (p<0.000), and psychological health domain (p=0.002). The logistic regression analysis showed that patients aged 40-49 years were more likely to experience distress than those aged ${\geq}60years$ (Odds ratios [OR]=2.992, 95% confidence interval [CI] 1.241-7.215). Moreover, the WHOQOL-BREF physical health domain was a predictive factor of distress (OR=0.777, 95% CI 0.692-0.873). Conclusions : A substantial proportion of patients are experiencing significant distress after BC surgery. It would be expected that distress management, especially in the middle-aged patients and in the domain of physical QOL (e.g., pain, insomnia, fatigue), from the early BC treatment stage might reduce chronic distress.

• Journal of Korean Society of Forest Science
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• v.84 no.4
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• pp.465-478
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• 1995

The objective of this study was to investigate the impacts of large-scale timber harvesting on the environment of a mature hardwood forest. To achieve the objective, the effects of harvesting on forest environmental factors were analyzed quantitatively using the field data measured in the study sites of Seoul National University Research Forests [(Mt.) Paekunsan] for two years(1993-1994) following timber harvesting. The field data include information on vegetation, soil mesofauna, physicochemical characteristics of soil, surface water runoff, water quality in the stream, and hillslope erosion. For comparison, field data for each environmental factor were collected in forest areas disturbed by logging and undisturbed, separately. The results of this study were as follows : The diversity of vegetational species increased in the harvested sites. However, the similarity index value of species between harvested and non-harvested sites was close to each other. Soil bulk density and soil hardness were increased after timber harvesting, respectively. The level of organic matter, total-N, avail $P_2O_5$, CEC($K^+$, $Na^+$, $Ca^{{+}{+}}$, $Mg^{{+}{+}}$) in the harvested area were found decreased. While the population of Colembola spp., and Acari spp. among soil mesofauna in harvested sites increased by two to seven times compared to those of non-harvested sites during the first year, the rates of increment decreased in the second year. However, those members of soil mesofauna in harvested sites were still higher than those of non-harvested sites in the second year. The results of statistical analysis using the stepwise regression method indicated that the diversity of soil mesofauna were significantly affected by soil moisture, soil bulk density, $Mg^{{+}{+}}$, CEC, and soil temperature at soil depth of 5(0~10)cm in the order of importance. The amount of surface water runoff on harvested sites was larger than that of non-harvested sites by 28% in the first year and 24.5% in the second year after timber harvesting. The level of BOD, COD, and pH in the stream water on the harvested sites reached at the level of the domestic use for drinking in the first and second year after timber harvesting. Such heavy metals as Cd, Pb, Cu, and organic P were not found. Moreover, the level of eight factors of domestic use for drinking water designated by the Ministry of Health and Welfare of Korea were within the level of the first class in the quality of drinking water standard. The study also showed that the amount of hillslope erosion in harvested sites was 4.77 ton/ha/yr in the first year after timber harvesting. In the second year, the amount decreased rapidly to 1.0 ton/ha/yr. The impact of logging on hillslope erosion in the harvested sites was larger than that in non-harvested sites by seven times in the first year and two times in the second year. The above results indicate that the large-scale timber harvesting cause significant changes in the environmental factors. However, the results are based on only two-year field observation. We should take more field observation and analyses to increase understandings on the impacts of timber harvesting on environmental changes. With the understandings, we might be able to improve the technology of timber harvesting operations to reduce the environmental impacts of large-scale timber harvesting.

• Clinical and Experimental Pediatrics
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• v.51 no.5
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• pp.468-473
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• 2008

Purpose : Iron-deficiency anemia (IDA) is still one of the most common nutrient deficiency disorders, despite improvements in general health and nutrition. This study was designed to investigate the diagnostic values of hematological profiles, including the level of ferritin, and to evaluate the knowledge of mothers on weaning practices for infants and young children with IDA. Methods : This study was conducted on 111 infants and young children from six to 40 months of age with IDA. Their parents completed a questionnaire. IDA was defined as a level of hemoglobin <11.0 g/dL, the presence of microcytosis, a level of ferritin <10.0 ng/dL, transferrin saturation <15%, or an 1 g/dL increase in the level of hemoglobin after iron administration. The questionnaire made inquiries into their weaning practices. Results : In 111 infants and young children aged from six to 40 months, the average level of Hb was $9.5{\pm}1.0g/dL$. The prevalence of ferritin level (>10 ng/dL) was 48.6%, in spite of IDA. Seventy-four infants (66.7%) began to wean between four and six months, and 37 infants (33.3%) after seven months of age. The main food given after weaning was rice gruel. The weaning periods showed a significant relationship to the severity of anemia (P<0.05). There was no significant difference in the severity of anemia in terms of the educational levels of the mothers. Fifty-five mothers (49.5%) gave a wrong answer to a questionnaire describing that breast-fed infants aged over four months need to be fed with iron-sufficient food. Of all mothers, 49.6% took one month or more to complete the weaning process and 20% took three months or more. Conclusion : Many infants and young children with IDA have been provided with non-iron fortified foods and inadequate weaning. To improve nutritional status, especially among infants with iron deficiencies, nutritional education for mothers with infants at the weaning age must be increased and related programs must be implemented effectively.

• Journal of Nutrition and Health
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• v.50 no.2
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• pp.158-170
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• 2017

Purpose: The purpose of this study was to explore the relationship between milk intake and prevalence rates of chronic diseases using KNHANES data, and the significance of the relationship was tested based on meditators, socioeconomic status (income, education), dietary behaviors (smoking, alcohol drinking, breakfast, and eating out), and physical activity (walking, medium, and high). Methods: Using the 5th and 6th survey data of KNHANES, milk intake rates and presence of seven chronic diseases were summarized and analyzed by ANOVA for two groups of adult men and women as follows: hypertension, hypertriglyceridemia, low HDL-cholesterol, diabetes, abdominal obesity, obesity, and metabolic syndrome. The dependent variables for the presence of seven chronic diseases regressed with socioeconomic, dietary behavior, and physical activity variables according to Logistic models. The dependent variables for milk intake using predictor variables of socioeconomic, dietary behaviors and physical activity were analyzed according to Logistic models. Finally, the significant socioeconomic, dietary behavior, and physical activity variables in the above model along with milk intake as a control variable or mediator variable regressed with significant chronic diseases according to Logistic models. Results: Milk intake, socioeconomic status, dietary behaviors, and physical activity were significantly different among the two groups of adult men and women, which were also critical factors to the prevalence of chronic diseases. The dependent variable for prevalence of chronic diseases regressed with significant factors of socioeconomic status, dietary behavior, and physical activity variables according to chronic diseases using the control or mediator variable of milk intake and summarized as follows: For adult men, milk intake controlled the education effect on diabetes partly, alcohol on hypertension and hypertriglyceridemia, low HDL-cholesterol, metabolic syndrome, breakfast on metabolic syndrome, eating out on obesity, and medium physical activity on hypertriglyceridemia. For adult women, household income on hypertriglyceridemia, diabetes, abdominal obesity, education level on hypertension, alcohol drinking, eating out, and walking activity on abdominal obesity, alcohol, breakfast, eating out, walking activity on low HDL-cholesterol, and medium physical activity on hypertriglyceridemia and low HDL-cholesterol were partly controlled by milk intake. Other significant socioeconomic status, dietary behavior, and physical activity variables related to prevalence of chronic diseases were fully controlled or mediated by milk intake. Conclusion: This study shows that milk intake (daily more than 200 g) prevents chronic diseases such as hypertension, hypertriglyceridemia, low HDL-cholesterol, diabetes, obesity, abdominal obesity, and metabolic syndrome.

• Journal of Nutrition and Health
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• v.15 no.4
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• pp.235-241
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• 1982

Studies were carried out on seven young, adult caucasian males to determine the short-term effects of protein(animal or plant)and calcium intakes on the excretion of urinary calcium. The subjects were studied on a self-selected diet for a period of seven days. Mean daily protein and calcium intakes were $103{\pm}31\;g$ and $1237{\pm}594mg$ respectively. Variation among subjects in the mean urinary calcium excretion per 24 hour was from $121{\pm}40$ to $258{\pm}104mg$. When the protein intake of all aubjcts was divided in to four levels : low (x=53g), medium (87g), intermediate (117g) and high(153g), The mean urinary calcium was $179{\pm}53$, $189{\pm}73$, $184{\pm}55$ and $264{\pm}84mg$, respectively. Urinary calcium increased significantly with an increase in protein intake. The calcium excretion was seriously increased with the protein intake above the intermediate level. Animal protein intake was more closely related to urinary calcium excretion than plant protein. There was a significant difference in the urinary calcium excretion when calcium intakes increased from low(x=544mg) to interne-diate levels (1232 mg). However, the difference between intermediate and high levels (1834mg) was not significant. Urinary calcium was $169{\pm}46mg$ on the low calcium diet, $196{\pm}71mg$ on the medium, and $222{\pm}21mg$ on the intermediate calcium intake, Calcium excretion was more closely related to changes in protein intake than to changes in calcium intake. Some nutritional implications can be drawn from this research. Protein intakes above the intermediate level (117g) are not recommendable. An over intake of calcium, however, may not be a serious problem for the calcium balance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1011-1017
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• 2002

The aim of this study was to investigate nutrition education effect in the long term and short term nutrition education intervention for childhood obesity. Seventy-seven obese children aged seven to twelve who visiting obesity clinic in a university hospital were given nutrition education therapy. Long-term as well as short-term education effect had been measured based on reducing level of Body Mass Index (BMI), Relative Body Weight (RBW) and lipid profile as well as dietary behavior. Identification of factors influencing the effect of nutrition education had been tested using multiple regression analysis as well as Main Whitney test. The result showed that nutrition education intervention had a significant impact on reducing the level of BMI, RBW and lipid profile during long term and short term period. Duration of clinic visit and total number of clinic visit were the most significant factors for the short term effect for obesity treatment. However, frequent clinic visit per month was not significant factor on short term effect. Therefore sustained participation for nutrition education by the obese individual seems more important factors than other factors especially for short term effect. Although, there was the tendency of reducing weight with longer duration and frequent clinic visit, and changing health behavior, none of the factors showed statistically significant effect on the long term effect for the obesity treatment. The results may imply that more complex factors involved for the long term treatment of childhood obesity than short term treatment.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.2
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• pp.69-82
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• 2013

The purpose of this study is to evaluate the effect of Dulegil in Bukhansan National Park in dispersing peak climbing hikers, characterize each section of Dulegil and suggest ideas of improvement. This study was conducted based on the survey completed by visitors in all 21 sections of Dulegil. After the construction of Dulegil, the number of visit to Dulegil grew and it was analyzed that Dulegil attracted new visitors given that the rate of young people(aged 19~30) who visited for the first time was quite high. Regarding the frequency of peak climbing, 7.6% of the respondents said "decreased" and 46.2% said "increased", showing that Dulegil's effect to disperse peak climbing hikers is nominal. Seven qualities were evaluated regarding Dulegil's level of satisfaction. Out of those seven, the quality of recreational place and taking a walk achieved high scores of 3.74 and 3.61 respectively. The quality of culture and history scored the lowest with 3.09. The analysis on the characteristic of each section of Dulegil, reason of visit, and the visitors' level of satisfaction showed that Dulegil is now regarded as a place where they can improve their health through light exercise and walking. In addition, a positive effect can be expected for a long time since there are different ways of utilizing the resources of the National Park, such as getting in touch with nature, preserving ecology, learning history and enjoying beautiful landscapes. If infrastructure and programs specific to each section of Dulegil were improved in a long-term perspective, it would be effective to encourage peak climbers and enjoy the lower parts of the mountain.

• Women's Health Nursing
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• v.7 no.2
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• pp.212-228
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• 2001

This is a cross-sectional descriptive correlation study that aimed to understand the relationship between the level of sexual contacts during the dates and psycho-social factors in teenage girls who have or had boyfriends. The purpose of this study was to describe the relationship between sexual contacts and self-esteem and self- assertiveness. The subjects of the study were 6,130 teenage girls who have or had boyfriends. They were selected convienently 12,733 teenage girls from 254 secondary schools located in 7 large cities and 9 provinces in Korea. A structured questionaire was used it included items one general characteristics, the levels of sexual contacts, self-esteem and self-assertiveness. Seven levels of sexual contacts were rated they were holding a hand, putting arms around each other's shoulders, kiss, french kiss, touching breast, petting genitalia, and sexual intercourse during the dates. Self-esteem and self-assertiveness were measured by the "Self-esteem scale" of Rogenberg (1971) and the questionaires developed by S. B. Chang et al(2000), respectively. The self-reported questionaires were collected from October 2, to October 28, 2000 and analyzed by using SPSS 10.0 Program. The data were analyzed by descriptive statistics, reliability, One-way ANOVA with Duncan method & Scheffe method. The results of the analysis were as follows. 1.An average Percentage of the respondents who have (46.1%) or had (53.9%) boyfriends was 48.1% (n=6,130) and the most common sexual contact during the dates was french kiss (26.7%, n=1,634). While 7.5%(458) of respondents had a sexual intercourse, 13.7%(842) of respondents didn't have any sexual contact during the dates. 2. Distribution of starting point of the first sexual contact demonstrates that 1,950 respondents (31.8%) held partner's hand at the first date and 1,367 respondents (22.3%) put arms around each other's shoulders at the 2nd or 3rd date. Sexual contacts such as kiss, french kiss, touching breast, petting genitalia, or sexual intercourse were experienced mostly at the later than the 10th date. However, surprisingly large number(1.7%) of respondents had genital contact and sexual intercourses at the first date. 3. The means of self-esteem and self-assertiveness socres of the respondents who have or had boyfriends are 27.43$({\pm}4.03)$ and 17.96$({\pm}2.55)$, respectively. The range of scores for self esteem was 10-40, 40 with most self esteem. The range of scores for self assertiveness was 7-21, 21 with most self assertiveness. 4. As sexual contacts proceeded, the means of self-esteem and self-assertiveness values decreased. In detail, the respondents having no or light sexual contacts (kiss, putting arms around each other's shoulder, holding a hand) had similar self-esteem values($p{\leq}0.05$). However, ones having relatively intensive sexual contacts (french kiss, touching breast) showed significantly lower self-esteem values($p{\leq}0.05$). Same trend has been obtained for self-assertiveness value. 5. The higher values of self-esteem and self-assertiveness values the respondents had, the later they started the moderate sexual contact (kiss, french kiss) during the dates. Interestingly, among the respondents having intensive sexual contacts (petting genitalia, sexual intercourse) during the dates, those who experienced the such contacts at the first date or later than 10th date have higher self-esteem and self-assertiveness values than one experienced the such contacts during the 2nd$\sim$9th dates, giving U-shape curve. 6. There was a significant relationship between self-esteem and self-assertiveness in girls who have or had boyfriends($P{\leq}.001$). In conclusion, the research shows that self-esteem and self-assertiveness values are significantly related with the sexual contacts of the teenage girls who have or had boyfriends. These results strongly suggest that proper sex education program for teenage girls should contain the program on improving the self-esteem and self-assertiveness. We believe that sex education program is the one of the best ways to prevent the unwanted sexual contacts and pregnancy of teenage girls.

• Journal of Radiation Protection and Research
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• v.33 no.2
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• pp.77-86
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• 2008

This study attempted to provide reference materials for improving the behavior level in radiation safety managements by drawing a prediction model that affects the radiation safety management behavior because the radiation safety management of medical Cyclotrons, which can be used to produce radioisotopes, is an important factor that protects radiation caused diseases not only for radiological operators but average users. In addition, this study obtained follows results through the investigation applied from January 2 to January 30, 2008 for the radiation safety managers employed in 24 authorized organizations, which have already installed Cyclotrons, through applying a specific form of questionnaire in which the validity was guaranteed by reference study, site investigation, and focus discussion by related experts. The radiation safety management were configured as seven steps: Step 1 is a production preparation step, Step 2 is an RI production step, Step 3 is a synthesis step, Step 4 is a distribution step, Step 5 is a quality control step, Step 6 is a carriage container packing step, and Step 7 is a transportation step. it was recognized that the distribution step was the most exposed as 15 subjects (62.5%), the items of 'the sanction and permission related works' and 'the guarantee of installation facilities and production equipments' were the most difficult as 9 subjects (37.5%), and In the trouble steps in such exposure, the item of 'the synthesis and distribution' steps were 4 times, respectively (30.8%). In the score of the behavior level in radiation safety managements, the minimum and maximum scores were 2.42 and 4.00, respectively, and the average score was $3.46{\pm}0.47$ out of 4. Prosperity and well-being programs in the behavior and job in radiation safety managements (r=0.529) represented a significant correlation statistically. In the drawing of a prediction model based on the factors that affected the behavior in radiation safety managements, general characteristics, organization characteristics, and selfefficacy didn't show a significant path statistically in which the prosperity and well-being programs in job characteristics affected the behavior in radiation safety managements. Therefore, it is necessary to establish a strategy that improves the level of prosperity and well-being levels in job characteristics in order to increase the behavior in radiation safety managements. Thus, this study provides basic materials for the radiation safety management of Cyclotron through the full-scale investigation that is first applied in Korea.