• 대한치과기공학회지
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• 제44권2호
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• pp.31-37
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• 2022

Purpose: The aim of this study was to evaluate the accuracy of provisional crowns manufactured using a milling machine and a digital light processing (DLP) printer. Methods: A full-contour crown was designed using computer-aided design software. Provisional crowns of this design were manufactured using a milling machine and using a DLP three-dimensional (3D) printer (N=20). The provisional crowns were digitized with an extraoral scanner, and 3D deviation analysis was applied to the scanned data to confirm their accuracy. An independent t-test was performed to detect the significant differences, and the Kolmogorov-Smirnov test was used for analysis (α=0.05). Results: No significant differences were found among the precision of marginal surface between the printed and milled crowns (p=0.181). The trueness of marginal and internal surfaces of the milled crowns were statistically higher than those of the printed crowns (p=0.024, p=0.001; respectively). Conclusion: The accuracy of provisional crowns manufactured using a milling machine and a 3D printer differed significantly except with regards to the precision of the internal surface. However, all the crowns were clinically acceptable, regardless of the manufacturing method used.

• 한방재활의학과학회지
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• 제33권1호
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• pp.77-85
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• 2023

Objectives This study is designed to evaluate the safety of palmul-tang soft extract in healthy male volunteers. Methods Twelve healthy male volunteers were recruited. And this study was conducted in a single center. As a result of the laboratory test, the safety was evaluated by collecting vital signs of volunteers. Twelve subjects were assigned by serial number according to the registration order. For safety evaluation, blood samples were collected and vital signs were checked four times throughout the test period, including screening, pre-administration, post-administration (after 48 hours) and post-administration (after 7 days). The difference in variables was summarized as the mean±standard deviation. The normality was performed using Kolmogorov-Smirnov and Shapiro-Wilk test. If normality is satisfied, a paired t-test is applied. Otherwise, the Wilcoxon sign rank test, which is a nonparametric method, is applied. The significance was p<0.05. The incidence of all side effects is expressed as a percentage. Results In the case of red blood cell, hemoglobin, and hematocrit values, the result of normality test of variables for the difference value before and after administration is significant level p<0.05. However, all laboratory test values before and after administration did not deviate from the normal range. Also the deviations in the normal range could not be seen as significance related to this clinical trial. And no side effects related to clinical trial drugs were observed. Conclusions The soft extract of palmul-tang was considered safe for healthy male volunteers.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.160-160
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• 2023

Generally, Global Climate Models (GCM) cannot be used directly due to their inherent error arising from over or under-estimation of climate variables compared to the observed data. Several bias correction methods have been devised to solve this problem. Most of the traditional bias correction methods are one dimensional as they bias correct the climate variables separately. One such method is the Quantile Mapping method which builds a transfer function based on the statistical differences between the GCM and observed variables. Laux et al. introduced a copula-based method that bias corrects simulated climate data by employing not one but two different climate variables simultaneously and essentially extends the traditional one dimensional method into two dimensions. but it has some limitations. This study uses objective functions to address specifically, the limitations of Laux's methods on the Quantile Mapping method. The objective functions used were the observed rank correlation function, the observed moment function and the observed likelihood function. To illustrate the performance of this method, it is applied to ten GCMs for 20 stations in South Korea. The marginal distributions used were the Weibull, Gamma, Lognormal, Logistic and the Gumbel distributions. The tested copula family include most Archimedean copula families. Five performance metrics are used to evaluate the efficiency of this method, the Mean Square Error, Root Mean Square Error, Kolmogorov-Smirnov test, Percent Bias, Nash-Sutcliffe Efficiency and the Kullback Leibler Divergence. The results showed a significant improvement of Laux's method especially when maximizing the observed rank correlation function and when maximizing a combination of the observed rank correlation and observed moments functions for all GCMs in the validation period.

• Journal of Korean Neurosurgical Society
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• 제66권2호
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• pp.190-198
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• 2023

Objective : Low back pain (LBP) is a global health problem that affects the productivity of the patients. Several factors such as individual, occupational, and psychosocial factors increase the risk of LBP. However, only a few studies investigated those factors, especially in middle adulthood in Indonesia. Indonesia is a country with a young population that has been rapidly developing in recent years. This study was conducted to find out the factors associated with LBP in middle adulthood. Methods : This study is a cross-sectional observational analytic study using a convenience sampling method with a total sample of 3005 respondents. Data were collected using a questionnaire which was then analyzed using the chi-square test, Kolmogorov-smirnov, Spearman's Rank, and logistic regression test. Results : From the result of this study, it was found that the 12-month prevalence of LBP in middle-aged adults was 44,29%. Female (odds ratio [OR], 1.3; 95% confidence interval [Cl], 1.098-1.545; p=0.002), lack of physical exercises (OR, 0.87; 95% Cl, 0.794-0.959; p=0.005), high body mass index (OR, 1.09; 95% Cl, 1.009-1.187; p=0.002), stress level (OR, 1.26; 95% Cl, 1.088-1.458; p=0.002), and years of work experience (OR, 1.1; 95% Cl, 1.001-1.225; p=0.047) were determined as risk factors that significantly associated with LBP. Conclusion : LBP is quite common among middle-aged adults in Indonesia. Female gender, higher body mass index, lack of physical activity, stress level, and years of work experience were all potential risk factors for LBP in middle-aged adults. Middle-aged adults in Indonesia should be aware of LBP and avoid disabilities by identifying risk factors that may worsen LBP in the future.

• The Journal of Advanced Prosthodontics
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• 제16권2호
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• pp.115-125
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• 2024

PURPOSE. The purpose of this in vitro study was to investigate the fracture resistance, surface hardness, and color stain of 3D printed, CAD-CAM milled, and conventional interim materials. MATERIALS AND METHODS. A total of 80 specimens were fabricated from auto polymerizing polymethyl methacrylate (PMMA), bis-acryl composite resin, CAD-CAM polymethyl methacrylate resin (milled), and 3D printed composite resin (printed) (n = 20). Forty of them were crown-shaped, on which fracture strength test was performed (n = 10). The others were disc-shaped specimens (10 mm × 2 mm) and divided into two groups for surface hardness and color stainability tests before and after thermal cycling in coffee solution (n = 10). Color parameters were measured with a spectrophotometer before and after each storage period, and color differences (CIEDE2000 [DE00]) were calculated. The distribution of variables was measured with the Kolmogorov Smirnov test, and one-way analysis of variance (ANOVA), Tukey HSD, Kruskal-Wallis, Mann-Whitney U tests were used in the analysis of quantitative independent data. Paired sample t-test was used in the analysis of dependent quantitative data (P < .05). RESULTS. The highest crown fracture resistance values were determined for the 3D printed composite resin (P < .05), and the lowest were observed in the bis-acryl composite resin (P < .05). Before and after thermal cycling, increase in mean hardness values were observed only in 3D printed composite resin (P < .05) and the highest ΔE₀₀ value were observed in PMMA resin for all materials (P < .05). CONCLUSION. 3D printing and CAD-CAM milled interim materials showed better fracture strength. After the coffee thermal cycle, the highest surface hardness value was again found in 3D printing and CAD-CAM milled interim samples and the color change of the bis-acryl resin-based samples and the additive production technique was higher than the PMMA resin and CAD-CAM milled resin samples.

• Imaging Science in Dentistry
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• 제54권2호
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• pp.147-157
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• 2024

Purpose: The aim of this study was to explore the correlations of cone-beam computed tomographic findings with the apnea-hypopnea index in patients with obstructive sleep apnea. Materials and Methods: Forty patients with obstructive sleep apnea were selected from the ear-nose-throat (ENT) outpatient clinic, Faculty of Medicine, Mansoura University. Cone-beam computed tomography was performed for each patient at the end of both inspiration and expiration. Polysomnography was carried out, and the apnea-hypopnea index was obtained. Linear measurements, including cross-sectional area and the SNA and SNB angles, were obtained. Four oral and maxillofacial radiologists categorized pharyngeal and retropalatal airway morphology and calculated the airway length and volume. Continuous data were tested for normality using the Kolmogorov-Smirnov test and reported as the mean and standard deviation or as the median and range. Categorical data were presented as numbers and percentages, and the significance level was set at P<0.05. Results: The minimal value of the cross-sectional area, SNB angle, and airway morphology at the end of inspiration demonstrated a statistically significant association (P<0.05) with the apnea-hypopnea index, with excellent agreement. No statistically significant difference was found in the airway volume, other linear measurements, or retropalatal airway morphology. Conclusion: Cone-beam computed tomographic measurements in obstructive sleep apnea patients may be used as a supplement to a novel radiographic classification corresponding to the established clinical apnea-hypopnea index classification.

• 한방재활의학과학회지
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• 제34권3호
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• pp.89-96
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• 2024

Objectives This study is designed to evaluated the safety of peony root extract tablet in healthy male volunteers. Methods 12 healthy male volunteers were recruited, and this study was conducted by a single center. The safety was evaluated by collecting laboratory test and vital signs of volunteers. As the registration process, 12 subjects were assigned by serial number. To evaluate safety, vital signs were checked and blood samples were collected 4 times during the screening period, pre & post-administration (after 8 hours) and post-administration (after 7 days). The difference in variables was summarized by the mean±standard deviation. The normality test was carried out using the Shapiro-Wilk test and Kolmogorov-Smirnov test. When normality is fulfilled, a paired t-test is applied and the significance level was p<0.05. And the incidence of all adverse effects and serious adverse effects are shown in percentage. Results In the case of vital sign, body temperature (BT) (℃) was 0.06±0.05 ℃ (p=0.008), and there was a statistically significant difference in before and after administration. However, clinical symptoms were not occurred and BT (℃) of all subjects before and after administration showed values within the normal reference value. There was no significant difference from the control group in all other vital signs and laboratory test data. And no side-effects associated to clinical trial drugs were followed. Conclusions The peony root extract tablet was considered to be safe for healthy male volunteers.

• 한국습지학회지
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• 제17권2호
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• pp.184-192
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• 2015

습지 토양으로 인한 수질 악화를 저감할 수 있는 저관리형 습지 조성을 위한 기초연구로써 진행된 본 연구의 목적은 인공지반 위에 습지 조성 시 수체와 토양의 분리가 가능한 플랜터형 호안구조물이 설치된 습지의 수질 제어 기작을 연구하는 것이다. 실험구는 고무수조에 마사토를 채운 플랜터형 호안구조물을 적용하여 수체와 토양을 분리하였으며, 대조구는 고무수조에 마사토를 포설하여 수체에 직접 노출시켰다. 실험구와 대조구의 수질을 Kolmogorov-Smirnov Z 검정으로 분석한 결과, pH, BOD, SS, Chl-a, T-P, T-N에서 통계적으로 유의한 차이가 있는 것으로 나타나 플랜터형 호안구조물 적용 여부에 따른 수질 제어의 효과 차이를 입증하였다. 환경정책기본법에 근거한 수질 분석결과 수온과 EC는 실험구와 대조구가 비슷한 양상으로 나타났으며, pH와 DO는 두 메조코즘이 같은 등급에 속하였다. BOD, SS, Chl-a, T-P는 실험구가 더 높은 등급을 상회하는 것으로 평가되었으며, T-N은 대조구가 더 낮은 수치를 나타냈지만 수질의 등급이 같은 것으로 나타나 미미한 차이임을 알 수 있었다. 본 연구는 습지 조성 방식에 있어 플랜터형 호안구조물을 활용해 토양과 수체를 분리하여 습지를 조성하면 문제시 되어 오던 사면 침식으로 인한 육화 및 건조화 현상과 영양염류로 인한 녹조나 부영양화 현상 등을 예방하고, 식생대를 제어할 수 있음을 시사하였고, 특히 플랜터형 호안구조물을 활용한 습지 조성 시 수질 제어 기작을 통해 습지의 심미적, 생태적, 사회적, 경제적 가치를 증진시킬 수 있는 것에 대해 증명하였다. 따라서 본 연구의 결과는 향후 효율적인 수질 유지가 가능하여 관리조방적인 인공습지를 계획하고 조성하는데 기초 자료로 활용될 수 있을 것이다.

• 한국산학기술학회논문지
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• 제17권9호
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• pp.83-93
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• 2016

본 연구는 초등학교 비만아동을 위한 '26주-비만관리프로그램'을 개발하여 비만지수(체질량, 체지방률, 중성지방)와 자아존중감, 식이자기효능, 운동자기효능, 신체상에 미치는 효과를 검정한 비동등성 대조군 전후설계에 의한 유사실험 연구이다. 연구대상자는 초등학교 4~6학년 학생 중 체질량 $20kg/m^2$ 이상인 46명 아동으로 실험군 23명과 대조군 23명이었다. '26주-비만관리프로그램'은 12주의 집중관리와 14주의 추후관리로 이루어졌다. 집중관리 12주 동안에 집단교육(비만, 운동, 영양)은 12회, 식이 및 운동은 36회, 심리상담은 5회 진행되었고, 이어서 추후관리 14주 동안에 집단교육은 3회, 식이 및 운동실천 점검 3회, 심리상담은 1회 실시하였다. 수집된 자료의 분석은 Kolmogorov-Smirnov test, chi-square test, Fisher's exact probability, t-test, ANCOVA를 사용하였다. 연구결과 실험군에서 체질량($20kg/m^2$), 체지방률(15-20%), 중성지방($90mg/d{\ell}$)이 정상기준치 이상이었으나, 실험군의 체질량(F=94.869, p<.001), 체지방률(F=37.361, p<.001), 중성지방(F=7.907, p= .007)이 대조군보다 유의하게 감소하였다. 이어서 실험군의 자아존중감 점수(F=19.661, p<.001), 식이자기효능감 점수(F=16.942, p<.001), 운동자기효능 점수(F=9.363, p= .004), 신체상 점수(F=9.782, p= .003)가 대조군보다 유의하게 더 높았다. 이러한 결과를 통해 본 연구에서 개발된 '26주-비만관리프로그램'은 초등학교 비만아동들의 비만지수와 심리적 변인의 관리에 대한 효과적인 간호 중재임이 확인되었다.

• 대한치과보철학회지
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• 제61권3호
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• pp.179-188
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• 2023

목적. 이 연구의 목적은 알루미나 입자 공기분사 및 프라이머 표면처리가 각각 두 가지 종류의 지르코니아(3 mol% yttria-stabilized tetragonal zirconia polycrystal; 3Y-TZP, 5 mol% partially stabilized zirconia; 5Y-PSZ)와 레진시멘트의 전단응력에 미치는 영향을 평가하는 것이다. 재료 및 방법. 완전 소결된 14.0×14.0×2.0 mm 크기의 두가지 다른 종류의 지르코니아 시편(3Y-TZP, 5Y-PSZ)을 각각 40개씩 제작하고 400, 600, 800 그릿의 실리콘 카바이드 종이로 연마 후 에폭시 레진에 매립하였다. 이들을 각각 4개의 대조군, 50 ㎛ 알루미나 입자 공기분사 사용군, 프라이머 사용군, 50 ㎛ 알루미나 입자 공기분사와 프라이머로 표면을 처리한 한 후 레진시멘트(PANAVIA V5)로 접착하였다. 그 후 증류수(37℃)에 24시간 보관 후 전단결합강도 실험을 시행, Kolmogorov-Smirnov & Shapiro-Wilk test를 사용해서 정규성을 확인한 후, 모수적 방법인 이원배치분산분석을 사용하여 지르코니아 종류 및 표면처리 방법에 따른 전단결합강도의 상호작용 및 통계적 차이를 분석하였다. 이후 Dunnett T3를 이용해 사후검정을 하였다. 결과. 이배치분산분석 결과 지르코니아 종류에 따른 전단결합강도는 각 군간에 유의미한 차이를 보이지 않았지만(P > .05), 표면처리 방법에 따른 전단결합강도는 50 ㎛ 알루미나 입자 공기분사 사용군, 프라이머 사용군, 50 ㎛ 알루미나 공기 분사와 프라이머를 사용한 군에서는 유의미한 상관관계를 보였다(P < .05). Dunnett T3 사후검정 결과 지르코니아의 종류에 상관없이 전단결합강도는 샌드블라스팅 & 프라이머 > 프라이머 > 샌드블라스팅 > 대조군 순서로 나타났다(P < .05). 결론. 본 연구 결과에 따르면 지르코니아 종류에 따른 전단결합 강도 차이는 없었다. 지르코니아 표면의 기계적 화학적 표면처리를 동시에 했을 때 가장 높은 전단결합강도를 보였다.