• 한국세라믹학회지
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• 제45권6호
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• pp.345-349
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• 2008

$TiO_2$ coating ceramic tile for self-cleaning purpose was prepared by the precipitant dropping method using $TiCl_4$ as a precursor. $TiO_2$ film was formed on the ceramic tile by spray-coating technique and heat-treated at $500^{\circ}C$ for 1 h. The size and crystalline structure of $TiO_2$ particles were 15.3 nm and anatase phase. The outdoor exposure tests were conducted and the effects of outdoor exposure test conditions, such as exhaust concentration of contamination materials (test places), the UV light intensity (irradiation direction) and coating amounts of $TiO_2$ on the self-cleaning properties were investigated by the brightness measurements. As a results, self-cleaning property of $TiO_2$ coating tile was affected by the coating amount of $TiO_2$ however, not affected by the UV light intensity included in sun's ray (irradiation direction). $TiO_2$ coating ceramic tile can be utilized for exterior finishing materials because of self-cleaning property of $TiO_2$ coating tile.

• 한국치위생학회지
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• 제10권4호
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• pp.717-725
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• 2010

Objectives : This study was to determine the level of occupational exposure and quality of life and to investigate the effect of variables related occupational exposure on quality of life in dental hygienists. Methods : A survey questionnaire was mailed to dental hygienists from April 4 to May 15, 2010. The subjects were 256(56.9%), who were worked in dental hospital and clinic with mean age of $29.59{\pm}7.30$. Quality of life was measured using the WHOQOL-BREF. It consists of 26 items, each with 5-point likert scale. Self control of occupational exposure was measured using the 3-items. The data were analyzed with chi-square, t-test, one-way ANOVA, pearson correlation coefficients and multiple regression using the SPSS WIN 17.0 program. Results : Regarding quality of life, the subjects was a mean of 90.73 out of a maximum 130 points. The level of self control occupational exposure a mean of 3.20 out of a maximum 5 points. Self control of occupational exposure, frequency of panorama radiography, work experience of radiography had a significant impact on quality of life in dental hygienists. Conclusions : Based on the findings, occupational exposure is negatively associated with quality of life in dental hygienists. These results suggest that health promotion program should be considered various factors related occupational exposure in dental hygienists.

• 한국의류학회지
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• 제32권7호
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• pp.1149-1159
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• 2008

This study aims at examining how male college students' extent of mass media exposure affects their sociocultural attitude toward appearance and appearance orientation. It also investigates how these variables show difference depending on the individual's self-efficacy. For the study, data were collected from 397 male students by means of stratified random sampling. The results are as follows: 1. Male college students 'sociocultural attitude toward appearance was shown in two factors of appearance internalization and appearance awareness. Appearance orientation was shown in two factors of interest in appearance and interest in body weight. 2. Male college students were exposed to mass media in order of videos, movies, TV entertainment shows, music and movie magazines. The influence of video media was strong. 3. Male college students' extent of mass media exposure exerted indirect influence through sociocultural attitude toward appearance rather than exerting direct influence on appearance orientation. 4. Male college students' appearance orientation varied depending on the extent of self-efficacy, and higher self-efficacy showed higher appearance orientation and appearance attitude. Especially the group with higher self-efficacy showed higher appearance attitude when the extent of exposure to mass media increased.

• Journal of Electrical Engineering and Technology
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• 제4권4호
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• pp.546-551
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• 2009

In this paper, we describe a self-aligned fabrication method for a nano-patterned bottom electrode using flood exposure from the backside. Misalignments between layers could cause the final devices to fail after the fabrication of the nano-scale bottom electrodes. A self-alignment was exploited to embed the bottom electrode inside the glass substrate. Aluminum patterns act as a dry etching mask to fabricate glass trenches as well as a self-aligned photomask during the flood exposure from the backside. The patterned photoresist (PR) has a negative sidewall slope using the flood exposure. The sidewall slopes of the glass trench and the patterned PR were $54.00^{\circ}$ and $63.47^{\circ}$, respectively. The negative sidewall enables an embedment of a gold layer inside $0.7{\mu}m$ wide glass trenches. Gold residues on the trench edges were removed by the additional flood exposure with wet etching. The sidewall slopes of the patterned PR are related to the slopes of the glass trenches. Nano-scale bottom electrodes inside the glass trenches will be used in beam resonators operating at high resonant frequencies.

• 한국건설순환자원학회논문집
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• 제6권4호
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• pp.283-288
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• 2018

균열 자기치유 소재는 균열발생 시점부터 노출환경 조건에 따라 활성화되기 때문에 치유성능과 균열면의 노출환경 조건과의 관계 규명이 매우 중요하다. 이에 본 연구에서는 자기치유형 보수 모르타르의 치유성능에 노출환경 조건이 미치는 영향을 투수시험을 통하여 조사하였다. 균열시험체의 초기 균열폭에 대한 온도 및 습도의 영향을 조사한 결과, 양생온도의 영향은 미미하였으나, 건습변화에 의해서는 균열닫힘 현상이 발생하고 있음을 확인하였다. 그리고 자기치유형 보수 모르타르 시험체의 균열부위에서 생성된 치유물질은 calcite 광물로 확인되었다. 밀도가 높은 calcite 광물은 중력의 영향을 받아 침강하기 때문에, 균열면의 방향에 따라 치유성능에 다소 차이를 나타냈으며, 또한 대기노출 조건보다 습윤노출 조건에서 치유성능이 크게 향상되었다.

• The Journal of Advanced Prosthodontics
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• 제12권2호
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• pp.89-99
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• 2020

PURPOSE. The effects of four different self-adhesive resin cement materials on cell viability and apoptosis after direct and indirect exposure were evaluated using different cell culture techniques. MATERIALS AND METHODS. Self-adhesive cements were applied to NIH/3T3 mouse fibroblasts by the extract test method, cell culture inserts, and dentin barrier test method. After exposure periods of 24 h and 72 h, the cytotoxicity of these self-adhesive materials was evaluated using the MTT assay (viability) and the Annexin-V-FITC/PI staining (apoptosis). RESULTS. The lowest cell viability was found in cells exposed to BeautiCem SA for 24 h in the extract test method. Cell viability was reduced to 70.6% compared to negative controls. After the 72 h exposure period, viability rate of cell cultures exposed to BeautiCem SA decreased more than 2- fold (29.5%) while cells exposed to RelyX U200 showed the highest viability rate of 71.4%. In the dentin barrier test method, BeautiCem SA induced the highest number of cells in apoptosis after a 24 h exposure (4.1%). Panavia SA Cement Plus was the material that caused the lowest number of cells in apoptosis (1.5%). CONCLUSION. The used self-adhesive cements have showed different cytotoxic effects based on the evaluation method. As exposure time increased, the materials showed more cytotoxic and apoptotic effects. BeautiCem SA caused significantly more severe cytotoxic and apoptotic effects than other cements tested. Moreover, cements other than BeautiCem SA have caused necrotic cell death rather than apoptotic cell death.

• Journal of Preventive Medicine and Public Health
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• 제46권5호
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• pp.226-236
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• 2013

Objectives: The aim of this study was to examine the levels of serum 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and evaluate their association with age, body mass index, smoking, military record-based variables, and estimated exposure to Agent Orange in Korean Vietnam veterans. Methods: Serum levels of TCDD were analyzed in 102 Vietnam veterans. Information on age, body mass index, and smoking status were obtained from a self-reported questionnaire. The perceived exposure was assessed by a 6-item questionnaire. Two proximitybased exposures were constructed by division/brigade level and battalion/company level unit information using the Stellman exposure opportunity index model. Results: The mean and median of serum TCDD levels was 1.2 parts per trillion (ppt) and 0.9 ppt, respectively. Only 2 Vietnam veterans had elevated levels of TCDD (>10 ppt). The levels of TCDD did not tend to increase with the likelihood of exposure to Agent Orange, as estimated from either proximity-based exposure or perceived self-reported exposure. The serum TCDD levels were not significantly different according to military unit, year of first deployment, duration of deployment, military rank, age, body mass index, and smoking status. Conclusions: The average serum TCDD levels in the Korean Vietnam veterans were lower than those reported for other occupationally or environmentally exposed groups and US Vietnam veterans, and their use as an objective marker of Agent Orange exposure may have some limitations. The unit of deployment, duration of deployment, year of first deployment, military rank, perceived self-reported exposure, and proximity-based exposure to Agent Orange were not associated with TCDD levels in Korean Vietnam veterans. Age, body mass index and smoking also were not associated with TCDD levels.

• 가정간호학회지
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• 제31권1호
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• pp.30-43
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• 2024

Purpose: This study aimed to enhance health management and prevention strategies for precocious puberty by comparing the knowledge, motivation, and behaviors related to reducing exposure to endocrine disrupting chemicals (EDCs) between mothers of children with precocious puberty and those of typically developing children. Methods: Participants were 66 mothers of children with precocious puberty from a hospital and 71 mothers of typically developing children from an elementary school. The research questionnaire assessed knowledge of EDCs, motivation, self-efficacy, and behaviors towards reduced exposure to EDCs, in addition to general characteristics of children with precocious puberty. Data analysis utilized descriptive statistics, chi-square tests, t-tests, ANOVA, and Pearson's correlation. Results: There were statistically significant differences in self-efficacy (p=.015) and behavior (p=.001) regarding reduced exposure to EDCs between the two groups. Behaviors toward reduced exposure to EDCs were positively associated with knowledge of EDCs, motivation, and self-efficacy among mothers of children with precocious puberty. Additionally, these behaviors correlated positively with knowledge of EDCs, motivation, self-efficacy, and the child's birth weight and waist circumference among mothers of typically developing children. Conclusion: The results of this study revealed that mothers of children with precocious puberty exhibited less proactive behavior in reducing exposure to EDCs compared to mothers of typical children. Therefore, it is important to foster interest in the impact of environmental factors, beyond characteristic factors, on behaviors aimed at reducing exposure to EDCs.

• 한국산업보건학회지
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• 제28권3호
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• pp.267-272
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• 2018

Objective: This study aimed to test the accuracy of self-reported information used in indirect estimation of pesticide exposure. Methods: To do so, self-reported values on the duration of pesticide application per day were compared with observed values. The number of days of pesticide application per year as recorded in self-administered logs was compared with recalled values. Results: It was found that participants underestimated the duration and frequency of actual pesticide use. High correlations were found between self-reported values and observed values, as well as between recalled values and recorded values. Conclusions: The reason might be that farmers unconsciously under-recall the application of pesticide since many customers prefer eco-friendly agricultural products. Farmers thought the task of applying pesticides to be essential, and this may explain why the participants in this study tended to accurately recall their pesticide-related work.

• Fashion, Industry and Education
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• 제15권1호
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• pp.29-43
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• 2017

This study investigated how exposure to thin-ideal images affects social physical anxiety and body-esteem in relation to individual levels of self-consciousness. A survey questionnaire was administered to a convenience sample of 119 female college students. Sixty-seven of the 119 participated in a posttest session. The mean comparisons of social physique anxiety and body-esteem scores between pretest and posttest were conducted; no significant results were found. However, when participants were divided into two separate self-consciousness groups (high vs. low), the effect of media exposure on social physique anxiety were significant.