졸-겔법으로 합성된 폴리이미드/실리카 복합체의 환경적 물성에 관한 연구

박성수,홍성수,이성환,김성완,박재현,김지경,박희찬 한국환경과학회 2003 한국환경과학회지 Vol.12 No.4

Two types of polyimide/silica composite films were prepared using sol-gel method through hydrolysis and polycondensation of tetraethoxsilane(TEOS) with the polyamic acid(PAA) and end-capped PAA solution. Sample were characterized by the means of differential thermogravimetry, X-ray diffractometry, scanning electron microscopy, universal test, impedance analyzer, chemical resistance test, etc. All of the PAA/silanol solutions heat-treated at 300℃ for 6h were transformed to polyimide/silica composites. It has been demonstrated that the properties of polyimide/silica composites were affected by the amount of silica addition and the bond type existed between polyimide and silica.

Alginate 배양내에서 Transglutaminase가 연골막세포에 미치는 영향

박정선,공차배,김충현,안현정,정미현,성상철,김희중,조현철,이상훈,이명철 대한정형외과연구학회 2003 대한정형외과연구학회지 Vol.6 No.2

Park's Vector Pattern의 왜곡률 분석에 의한 BLDC 모터의 권선 고장진단

이대성(Dae-Seong Lee),김준영(Jun-Yong Kim),양철오(Chul-Oh Yang),송명현(Myung-Hyun Song),박규남(Song, Kyu-Nam Park) 대한전기학회 2013 대한전기학회 학술대회 논문집 Vol.2013 No.7

주파수 응답 함수를 이용한 평면 밀링에서의 채터 예측

홍성욱,박중윤,김현수,박재현,박창용 金烏工科大學校 産業技術開發硏究院 1999 産業技術開發硏究 Vol.15 No.-

The present paper investigates the chatter stability of a milling spindle-workpiece system in face milling process. To this end, a new method using frequendy response function is adopted for predicting the chatter vibration. A compliant workpiece is used to make the spindle-workpiece system easily exposed to chatter vibration. The entire experimental procedure, including measurement of frequency response function and cutting coefficients, is demonstrated. The experimental result shows that the chatter stability prediction method using frequendy response function is of great use in face milling process.

급성 심근허혈에 의해 윤발된 승모판 폐쇄부전의 기전에 관한 실험적 연구

강덕현,송현,송재관,김현숙,이재환,임희영,이재원,박성욱,박승정,송명근 대한순환기학회 1999 Korean Circulation Journal Vol.29 No.8

Comparison of Hypertension Prediction Analysis Using Waist Measurement and Body Mass Index by Age Group

So Hyun Park,Seong-Gil Kim 질병관리본부 2018 Osong Public Health and Research Persptectives Vol.9 No.2

Osong Public Health Res Perspect > 9(2); 2018 > Article Original Article Osong Public Health and Research Perspectives 2018;9(2):45-49. DOI: https://doi.org/10.24171/j.phrp.2018.9.2.02 Comparison of Hypertension Prediction Analysis Using Waist Measurement and Body Mass Index by Age Group So Hyun Parka, Seong-Gil Kimb,* aDepartment of Physical Therapy, Youngsan University, Yangsan, Korea bDepartment of Physical Therapy, Uiduk University, Gyeongju, Korea *Corresponding author: Seong-Gil Kim, Department of Physical Therapy, Uiduk University, Gyeongju, Korea, E-mail: niceguygil@gmail.com Received September 11, 2017 Revised December 27, 2017 Accepted January 16, 2018 Copyright ©2018, Korea Centers for Disease Control and Prevention (open-access, http://creativecommons.org/licenses/by-nc-nd/4.0/): This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Abstract Objectives The purpose of this study was to evaluate hypertension with simple anthropometry data related to obesity in Korean adults and identify whether age specific waist circumference (WC) may be a useful screening tool for determining hypertension. Methods Subjects (n = 571) were classified into 3 groups by age; young (18–39 years), middle aged (40–64 years), and old aged (≥ 65 years). Correlations between demographic and anthropometric parameters and hypertension were performed using Spearman correlation analysis. Logistic regression analysis and ROC (receiver operating characteristics) curves were also analyzed for correlations with hypertension. Results Spearman correlation analyses, age, gender, WC, and body mass index were positively correlated with hypertension. When logistic regression analysis was performed, increased age and increased WC was associated with a higher incidence of hypertension, although gender and body mass index were not significantly related to hypertension. In ROC analysis of WC for hypertension demonstrated that patients in the old age group showed higher WC cutoff value than patients in the young and middle aged groups. Conclusion The findings of this study demonstrate that WC may be a useful predictor of hypertension incidence among demographic and anthropometric factors in Korean adults. In addition, WC in the young population was more sensitive to the incidence of hypertension than in the elderly population.

NSIP와 BOOP의 고해상전산화단층촬영 소견과 비교

백상현,박재성,차장규,홍현숙,김대호,박성진,조준희,이혜경,최진수 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.2

Purpose: BOOP and NSIP also share similar clinical features such as subacute flu-like illness, the finding of bronchoalveolar lavage, the result of pulmonary function test and more favourable outcome than usual interstitial pneumonia(UIP). The author try to compare the HRCT findings of NSIP with BOOP by pattern and distribution of diseases. Materials and Methods: HRCT findings of histopathologically proven NSIP(Group Ⅰ; 6, Group Ⅱ; 7, Group Ⅲ; 2) in 15 patients(5 male, 10 female, age range, 39-69 years; mean age, 53 years), BOOP in 15 patients(6 male, 9 female, age range, 26-76 years; mean age, 52 years) were reviewed retrospectively. Results: The common pattern of the two diseases was admixed consolidation, ground glass attenuation & reticular densities with/without architectural distortion(NSIP; 53.3%, BOOP; 46.7%). The main component of the pattern wan predominantly consolidation(NSIP; 46.7%, BOOP; 73.3%) and ground glass attenuation(NSIP; 40.0%, BOOP;20.0%). Architectural distotion was more provinent finding with NSIP(mild ; 3, moderate ; 4, severe; 2) compared with BOOP(mild; 7, moderate; 2, severe; 0). The predominant overall distribution was lower lung, peribronchovascular & peripheral lung field in both of the two entities(NSIP;73.3%, BOOP; 73.3%). Peribronchovascular involvement was more common with NSIP(100%) than BOOP(80%), whereas peripheral involvement was more common with BOOP(93.3%) than NSIP(80%). Conclusion: The HRCT findings of NSIP and BOOP were similar in pattern and distribution. But NIP manifested more frequently ground-glass attenuation, whereas BOOP showed more frequently consolidation. Architectural distortion was more severe with NSIP than BOOP. NSIP invoved more frequently peribronchovascular space and BOOP were more common in peripheral lung field.

Correlations between the Growth Period and Fresh Weight of Seed Sprouts and Pixel Counts of Leaf Area

( Daesik Son ),( Soo Hyun Park ),( Soo Chung ),( Eun Seong Jeong ),( Seong Min Park1 ),( Myong Kyoon Yang ),( Hyun Seung Hwang ),( Seong In Cho ) 한국농업기계학회 2014 바이오시스템공학 Vol.39 No.4

Purpose: This study was carried out to predict the growth period and fresh weight of sprouts grown in a cultivator designed to grow sprouts under optimal conditions. Methods: The temperature, light intensity, and amount of irrigation were controlled, and images of seed sprouts were acquired to predict the days of growth and weight from pixel counts of leaf area. Broccoli, clover, and radish sprouts were selected, and each sprout was cultivated in a 90-mm-diameter Petri dish under the same cultivating conditions. An image of each sprout was taken every 24 hours from the 4th day, and the whole cultivating period was 6 days, including 3 days in the dark. Images were processed by histogram inspection, binary images, image erosion, image dilation, and the overlay image process. The RGB range and ratio of leaves were adjusted to calculate the pixel counts for leaf area. Results: The correlation coefficients between the pixel count of leaf area and the growth period of sprouts were 0.91, 0.98, and 0.97 for broccoli, clover, and radish, respectively. Further, the correlation coefficients between the pixel count of leaf area and fresh weight were 0.90 for broccoli, 0.87 for clover, and 0.95 for radish. Conclusions: On the basis of these results, we suggest that the simple image acquisition system and processing algorithm can feasibly estimate the growth period and fresh weight of seed sprouts.

자가공명영상을 이용한 정신분열병 환자의 뇌량 면적 측정

박홍석,이정섭,황성혜,김창현 大韓神經精神醫學會 1999 신경정신의학 Vol.38 No.5

연구목적 : 본 연구에서는 정신분열병의 병태생리에 뇌량이 관여하는지 확인하기 위해 초발 및 만성 정신분열병 환자, 대조군의 뇌량의 영역을 측정하였다. 방 법 : 국립의료원에 입원한 23명의 정신분열병 환자(남자 15명, 여자 8명)와 단순 두통 또는 어지럼증을 호소하여 내원한 23명의 외래환자를 대조군으로 하여 뇌자기공명영상을 얻었으며, 남자는 26명, 여자는 20명 이었다. 환자군중 초발군은 13명, 만성군은 10명이었다. 정중시상평면에서 뇌량을 7개 영역으로 구분하여 NIH Image 1.60프로그램으로 분석하였으며, 정중시상평면의 대뇌면적도 구하였다. 이렇게 구한 각 뇌량척도들은 t-test를 이용하여 대조군과 비교하였으며, 성별에 따른 차이는 ANOVA를 이용하였으며, 이후 대뇌면적을 공변량으로 하여 ANCOVA를 시행하였다. 또한 초발군과 만성환자군, 대조군의 비교는 나이와 대뇌면적을 공변량으로하여 MANCOVA를 시행하였다. 결 과 : 환자군과 대조군 사이의 총뇌량의 평균면적과 각 7부분의 평균면적을 비교한 결과 환자군이 제 3, 제 6 뇌량영역을 제외하곤 대조군에 비해 평균면적이 작은 것으로 나왔지만 통계적 유의성은 없었다. 성별에 따라 비교한 결과 통계적 유의성은 관찰되지 않았지만 남자환자는 대조군에 비해 작고, 여자환자의 경우에는 큰 것으로 확인됐다. 초발과 만성환자군으로 나누어 대조군과 비교해 본 결과, 통계적 유의성은 없었으나 초발환자군이 만성환자군에 비해 모든 뇌량척도가 작았고, 만성환자군은 대조군보다 총뇌량의 평균면적이 컸으나 초발군은 대조군 보다 작았다. 결 론 : 본 연구의 결과 정신분열병 환자에서 유의한 뇌량의 형태적 이상을 확인하지는 못했지만 이전 연구들에서도 다양한 결과들을 보고하고 있으며, 이는 정신분열병이 생물학적 및 임상적으로 각기 다른 표현형을 가지고 있다는 가설로 설명할 수 있다. Objectives : This study was performed to determine whether the corpus callosum is involved in pathophysiology of schizophrenia and measured corpus callosal areas of first episode, chronic schizophrenic patients and controls. Methods : We obtained the brain magnetic resonance imaging of 23 schizophrenic inpatients(15 males, 8 females) and 23 controls(11 males, 12 females) with simple headache or dizziness. Among the schizophrenic group, first episode patients were 13, chronic patients were 10. In mid-sagittal plane, the corpus callosum was divided into 7 areas and the cerebral area was measured. This data was analyzed with NIH image 1.60 software. We compared the corpus callosal areas of schizophrenics with controls by t-test and by ANOVA according to sex. Thereafter, ANCOVA was performed with mid-sagittal cerebral area as covariant. Comparison of first episode, chronic schizophrenics and controls was carried out by MANCOVA that was adjusted with age and mid-sagittal cerebra area. Results : The schizophrenics, compared with controls, had smaller corpus callosal areas except for the 3rd, 6th callosal area, but statistical significance was absent. According to sex, male schizophrenics had insignificantly smaller total callosal areas than male controls and female schizophrenics had larger ones. In comparison of first episode, chronic schizophrenic patients and controls, first episode patients had smaller every corpus callosal areas than chronic ones, chronic ones had larger total callosal area than controls and first episode ones had smaller total area than controls, but statistical significances were absent also. Conclusion : Our study did not reveal the structural abnormality of corpus callosum in schizophrenic patients, but many controversial results have been reported in other studies. This inter-study inconsistency could be explained by the hypotheses of not only clinical but also biological different phenotypes within the schizophrenia.

Li₂ZrO₃계의 CO₂반응에 따른 전기적 성질

박진성,이현규 조선대학교 생산기술연구소 1999 生産技術硏究 Vol.21 No.2

A carbon dioxide gas sensor was studied as a function of temperature and CO₂concentration In the Li₂ZrO₃ system. Lithium zirconatet(Li₂ZrO₃) was synthesized by the heat-treatment of zirconia(ZrO₂) and Lithium carbonate(Li₂ZrO₃). The specimens were prepared both as bulk disks. 10mm in diameter and 1.0mm thickness, and thick films on an alumina substrate. Lithium zirconate readily responded to CO₂ concentration from 0.1% to 100% in the range of 450℃ to 650℃. The sensitivity to CO₂ was dependent on the measuring temperature. Lithium zirconate(Li₂ZrO₃) decomposes into Li₂ZrO₃ and ZrO₂ after the reaction with CO₂ in the range of 450℃ to 650℃, and Li₂ZrO₃ changes into Li₂O and CO₂ above 650℃. The material showed difficulty with reversibility and recovery. The optimum temperature for the highest sensitivity is around 550℃.