• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.332-333
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• 2005

In this study, in order to develop low temperature sintering piezoelectric actuator, $Pb(Mg_{1/2}W_{1/2})_{0.03}(Ni_{1/3}Nb_{2/3})_x(Zr_{0.50},Ti_{0.50})_{1-x-0.03}$ (PMW-PNN-PZT) ceramic systems were fabricated using $CaCO_3-Li_2CO_3$ sintering aid and their dielectric and piezoelectric properties were investigated with the variation of PNN substitution. The piezoelectric actuator requires high piezoelectric constant $d_{33}$ and high electromechanical coupling factor kp. At the PMW-PNN-PZT ceramics with 9mol% PNN substitution sintered at $900^{\circ}C$, the density, electromechanical coupling factor kp, dielectric constant, piezoelectric constant $d_{33}$ and mechanical quality factor Qm showed the excellent values of 7.86 [$g/cm^3$], 0.584, 1881, 485 [pC/N] and 76, respectively for piezoelectric actuator application.

• 한국안전학회지
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• 제35권3호
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• pp.105-115
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• 2020

This study compares the difference of fit factors (FF) and visual acuity according to masks and eyeglasses preferences for 54 participants. We the precautions and behaviors of discomfort when wearing masks of eyewear wearers. Contact lens discomfort and priority action of complaints was investigated Glasses fitting factors is Optical Center Height(OH), Vertex Distance(VD) and Pantoscopic Angle(PA). We measured those factors and expressed by the ratio of standard point and change point. Quantitative fit factor was measured by Portacount Pro+ 8038. Also, we selected to 6 exercises among 8 exercises OSHA QNFT (Quantitative Fit testing) protocol to measure the fit factors. The pass/ fail criterion of FF was set at 100. Visual acuity(VA) test chart is developed by Chunsuk Han was used, Descriptive statistics was performed. Descriptive statistics(SAS ver 9.2), it is used geometric means, Wilcoxon analysis(P=0.05) When wearing the mask preferentially, fit factor(FF) was high according to the step of glasses fitting parameter. on the other hand, when the glasses first choice, the visual acuity(VA) was high. there was no significant difference. In the case of fit factor (FF), mask first choice/ glasses first choice is OH (p=0.671/ p=0.332), VD (p=0.602/ p=0.571) and PA (p=0.549/ p=0.607). Visual acuity (VA), mask first choice/ glasses first choice is OH (p=0.753/ p=0.386), VD (p=0.815/ p=0.557) and PA (p=0.856/ p=0.562). The workers of workplace and office chose glasses but occupational health workers and students chose mask. In case of discomforts, it was suggested to remove the mask and tolerate discomforts. The main discomforts and usual action of lens were dryness, hyperemia, foreign body sensation, ophthalmodynia, decreased vision and glasses wearing. Therefore, it is necessary to develop a mask wearing method education program considering glasses fitting and develop a hybrid model that minimizes inconvenience when wearing glasses and a mask at the same time.

• Asian-Australasian Journal of Animal Sciences
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• 제29권1호
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• pp.134-141
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• 2016

To investigate the role of polysaccharide from Acanthopanax senticosus (ASPS) in preventing lipopolysaccharide (LPS)-induced intestinal injury, 18 mice (at 5 wk of age) were assigned to three groups with 6 replicates of one mouse each. Mice were administrated by oral gavage with or without ASPS (300 mg/kg body weight) for 14 days and were injected with saline or LPS at 15 days. Intestinal samples were collected at 4 h post-challenge. The results showed that ASPS ameliorated LPS-induced deterioration of digestive ability of LPS-challenged mice, indicated by an increase in intestinal lactase activity (45%, p<0.05), and the intestinal morphology, as proved by improved villus height (20.84%, p<0.05) and villus height:crypt depth ratio (42%, p<0.05), and lower crypt depth in jejunum (15.55%, p<0.05), as well as enhanced intestinal tight junction proteins expression involving occludin-1 (71.43%, p<0.05). ASPS also prevented intestinal inflammation response, supported by decrease in intestinal inflammatory mediators including tumor necrosis factor ${\alpha}$ (22.28%, p<0.05) and heat shock protein (HSP70) (77.42%, p<0.05). In addition, intestinal mucus layers were also improved by ASPS, as indicated by the increase in number of goblet cells (24.89%, p<0.05) and intestinal trefoil peptide (17.75%, p<0.05). Finally, ASPS facilitated mRNA expression of epidermal growth factor (100%, p<0.05) and its receptor (200%, p<0.05) gene. These results indicate that ASPS can prevent intestinal mucosal barrier injury under inflammatory conditions, which may be associated with up-regulating gene mRNA expression of epidermal growth factor and its receptor.

• 중소기업융합학회논문지
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• 제6권3호
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• pp.65-69
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• 2016

백내장이 있는 45~85세 총 119명의 백내장 수술 전후의 굴절이상 변화도를 알아보기 위하여 굴절이상과 각막굴절력을 power vector에 의하여 M, $J_0$, $J_{45}$ 3가지 성분으로 분석하였다. 등가구면 굴절력인 M 성분은 백내장 수술 전 $-0.29{\pm}2.38D$에서 수술 후 $-0.18{\pm}0.69D$로, $J_0$성분은 $-0.34{\pm}0.68D$에서 $-0.05{\pm}0.42D$로, $J_{45}$성분은 $0.11{\pm}0.45$에서 수술 후 $0.02{\pm}0.17$로 변화하였다. 각막평균 굴절력은 백내장 수술 전 $44.11{\pm}1.61D$에서, 백내장 수술 후 $44.20{\pm}1.58D$로, $J_0$성분은 $0.01{\pm}0.50D$에서, $0.08{\pm}0.49D$로 $J_{45}$성분은 $0.02{\pm}0.29$에서, $0.08{\pm}0.49$로 변화하였다. 굴절이상에 대한 수술 전후 상관관계는 $J_0$성분이 가장 높은 상관성이 있는 것으로 나타났고, 각막굴절 성분에 대한 상관관계는 평균 각막굴절력이 가장 높은 상관성이 있는 것으로 나타났으며, 각막굴절력 성분이 굴절이상 성분보다 더 높은 상관관계를 나타냈다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.63-67
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• 1996

In this paper, effect of MnO$_2$ addition(0, 0.1, 0.2, 0.3, 0.5wt%) on the microstructure, dielectric and piezoelectric properties of [xPMW - (0.15-x) PNN] - [yPT-(0.85-y)PZ] (x=0, 0.01, 0.02, 0.03, 0.05, y = 0.35, 0.40, ().425, 0.45, 0.5) were investigated. When Ti/Zr ratio was 1.0, dielectric and piezoelectric properties were highest value. With PMW 2mol%, dielectric constant, dielectric constant (d$\_$33/, d$\_$31/) and electromechanical coupling factor (kp, k$\_$31/) were highest values of 1995, 479, 186(x10$\^$-12/C/N), 0.61, 0.36, respectively. With the addition of MnO$_2$, dielectric constant, electromechanical coupling factor (kp, k$\_$31/) were decreased, but with 0.3wt% MnO$_2$, eletromechanical coupling factor was highest value of 0.63. With the addition of MnO$_2$, mechanical quality(Q$\_$m/ was increased.

• 한국치위생학회지
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• 제14권6호
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• pp.951-959
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• 2014

Objectives: The purpose of this study was to find out the fear of dentist care, subjective recognition of dental health, and quality of life in the male high school students and to analyze the influencing factors on dental health care. Methods: A self-reported questionnaire was filled out by 243 special high-school in Deagu province from March 3 to March 14, 2014. The questionnaire consisted of general characteristics of the subjects(5 questions), subjective recognition of health and activities to improve health(6 questions), dental fear(20 questions), oral health related quality of life(16 questions). The instrument for dental fear was adapted from measured by Berggren Dental Fear Survey(DFS). A total of 20 DFS questions included treatment avoidance(8 questions), stimulus reaction(6 questions), and physiological reaction(5 questions) and score by Likert 5 scale. Cronbach alpha was 0.974 in the study. Oral health related quality of life was measured by 16 questions of CPQ11-14 for the adolescents by Lau. CPQ11-14 consisted of oral symptoms(4 questions), functional restriction(4 questions), and emotional wellbeing(4 questions). The instrument was score by Likert 5 scale and Cronbach alpha was 0.9354 in the study. Data were analyzed using SPSS 18.0 program for ANOVA and multiple regression analysis. Results: Fear of dentist care showed significant differences in treatment avoidance factor(p<0.001), stimulus reaction factor (p<0.05), and physiological reaction factor(p<0.001). The factors depended on subjective recognition of health and health-improving activities and differences in treatment avoidance factor(p<0.05) and physiological reaction factor(p<0.01). The dental symptoms factors showed significant differences in health recognition(p<0.001), interest in health(p<0.001), alcohol drinking status(p<0.001) and regular meal(p<0.001). While function limit factors showed differences in health recognition (p<0.001), interest in health(p<0.001), smoking(p<0.001), alcohol drinking(p<0.001) and regular meal(p<0.001). Mental and social stabilities factors showed significant differences in health recognition(p<0.001), interest in health(p<0.001) and alcohol drinking status(p<0.001). Among the factors influencing on the quality of life in dental health, interest in health(p<0.005), alcohol drinking(p<0.005) and physiological reaction in the midst of fear of dentist care(p<0.001) were the significant impact factor. Conclusions: It is necessary to develop a continuous and systematical program of dental health and dental care by experts so that the students can reduce the fear of dentist care by regular dental checkup and preventive treatment and care.

• 한국안광학회지
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• 제3권1호
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• pp.189-199
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• 1998

완성안경의 광학적 허용요차에 대한 system을 안경처방서 작성시 환경, 주시거리, 하방 주시각, 테의 늘어남, 정정간 거리(VD), 토릭렌즈의 축, 렌즈의 기울기 등의 누적 오차 합 형태로 만들었다. 굴절력(D)에 따른 $O{\cdot}C$의 허용치 크기(T) 관계를 $T=T_0e^{-aD}$으로 주어지고 여기서, $T_0$는 굴절력이 0인 평면렌즈의 허용치 크기이고, ${\alpha}$는 허용치 factor이다. RAL-915에 대응하는 새로운 형태의 허용오차를 적용하는 경우, 허용오차가 큰 방향에 대해서는 허용치 factor ${\alpha}$는 $0.166(T_0=5.90)$이고, 허용오차가 작은 방향에 대해서는 허용치 factor ${\alpha}$는 $0.166(T_0=2.95)$ 값을 갖는다.

• Toxicological Research
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• 제8권1호
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• pp.49-61
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• 1992

Recombinant granulocyte-macrophage colony stimulating factor was subcutaneously administered to both sexes of Sprague-Dawley rats at the doses of 0, 0.5, 1 and 2mg/kg of body weight five days per week for 4 weeks to evaluate the subchronic toxicity. There were decreased 1 and 2 mg/kg. In the serum, changes were decreased alkaline phostatase(ALP) in the female groups dosed at 1 and 2mg/kg, and increased glutamic oxaloacetic transaminiase (GOT)in the male groups dosed at 0.5 and 2.0mg/kg.

• 정신신체의학
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• 제5권2호
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• pp.168-175
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• 1997

본 연구에서는 부모의 체질량 지수로 알아보는 비만의 가족력, 출생시 체중, 모유 또는 분유 수유, 어린이의 식사습관 및 생활 습관, 부모의 학력 부모의 식이제한 태도 등의 변수들과 아동의 비만과의 상관관계를 검토하여 보았다. 1) 전체 대상 아동 110명중 20.1%인 23명이 OBI가 20%이상인 비만아였다. 두 군에서 평균체중과 OBI는 유의한 차이를 나타내었고(p<0.01), 남아에서 유의하게 비만이 많았으며(p<0.05), 출생시 체중이나 수유의 종류 및 출생 순위등은 유의한 차이가 없었다. 2) 식사 및 생활 습관을 비교해 보면, 비만아에서 음식 먹는 속도가 빠른 경우가 유의하게 많았다(p<0.01) 먹고 싶은 충동을 견디기 어렵다는 경우, 불규칙한 식사, 인스턴트 식품이나 패스트 푸드를 좋아한다는 답변, 간식을 많이 한다, 기름진 음식을 좋아한다는 답변 등은 두군간에 유의한 차이가 없었다. 텔레비젼 시청이나 전자오락을 좋아한다는 답변도 두군간에 차이가 없었다. 3) 비만군에서 아버지의 연령 (p<0.05) 및 교육수준(p<0.05)이 유의하게 높았으며, 부모의 BMI는 두군간에 유의한 차이가 없었다. 4) 비만아동의 어머니에서 인지적 제한 요소인 factor 1과 탈억제 요소인 factor 2가 유의하게 높았으며(p<0.05). 공복감 요소인 factor 3은 두군간에 유의한 차이를 보이지 않았다. 어머니의 교육수준과 TFEQ의 factor 1은 상관관계를 보였으며(r=0.39, p<0.05), factor 1(r=0.38, p<0.05)과 factor 2의 점수가 높을수록 아동의 비만도는 증가하였다(r=0.34, p<0.05). 5) 만 5세 아동의 비만은 부모의 체질량 지수와 같은 유전적 요인보다는 아동 자신의 식사 습관이나 어머니의 식이제한 태도에 더 많은 영향을 받는다고 볼 수 있다.

• Clinical and Experimental Pediatrics
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• 제53권8호
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• pp.795-800
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• 2010

Purpose: B cell-activating factor (BAFF) is a tumor-necrosis factor (TNF) superfamily member best known for its role in the survival and maturation of B cells. BAFF activity is observed in naive cells as well as in effector/memory T cells. We aimed to explore whether BAFF in sputum is expressed at elevated levels in asthmatic airways and associated with eosinophilic inflammation, pulmonary function, and bronchial hyperresponsiveness in children. Methods: One hundred and fifty-four asthmatic children and 98 healthy children were enrolled in the study. Sputum supernatants were collected and sputum BAFF and eosinophil cationic protein (ECP) levels were measured. We performed pulmonary function tests and methacholine challenge tests, while measuring total eosinophil count, total serum IgE, and serum ECP in all subjects. Results: Asthmatic children had significantly higher levels of BAFF in induced sputum [26.50 (10.50-100.27) pg/mL] compared to healthy children [18.32 (7.68-44.63) pg/mL; $P$=0.011]. Sputum BAFF positively correlated with sputum eosinophils (${\gamma}$=0.406, $P$<0.001) and sputum ECP (${\gamma}$=0.789, $P$<0.001). Significant negative correlations were found between sputum BAFF and FEV1 (${\gamma}$=-0.291, $P$<0.001) or post-bronchodilator FEV1 (${\gamma}$=-0.334, $P$<0.001), whereas nonsignificant correlations were found between sputum BAFF and bronchial hyperresponsiveness, serum eosinophil count, and serum ECP. Conclusion: These findings suggest that BAFF may play a role in childhood asthma, and BAFF levels in sputum could be a supportive marker that represents airway inflammation, especially eosinophilic inflammation.