AN IN-SITU YOUNG'S MODULUS MEASUREMENT TECHNIQUE FOR NUCLEAR POWER PLANTS USING TIME-FREQUENCY ANALYSIS

Choi, Young-Chul,Yoon, Doo-Byung,Park, Jin-Ho,Kwon, Hyun-Sang Korean Nuclear Society 2009 Nuclear Engineering and Technology Vol.41 No.3

Elastic wave is one of the most useful tools for non-destructive tests in nuclear power plants. Since the elastic properties are indispensable for analyzing the behaviors of elastic waves, they should be predetermined within an acceptable accuracy. Nuclear power plants are exposed to harsh environmental conditions and hence the structures are degraded. It means that the Young's modulus becomes unreliable and in-situ measurement of Young's modulus is required from an engineering point of view. Young's modulus is estimated from the group velocity of propagating waves. Because the flexural wave of a plate is inherently dispersive, the group velocity is not clearly evaluated in temporal signal analysis. In order to overcome such ambiguity in estimation of group velocity, Wigner-Ville distribution as the time-frequency analysis technique was proposed and utilized. To verify the proposed method, experiments for steel and acryl plates were performed with accelerometers. The results show good estimation of the Young's modulus of two plates.

젊은 성인에서 흡연에 의한 상완동맥 내피기능의 부전에 관한 연구

이상철,권영주,방덕원,이선해,이보영,김지욱,김영훈,온영근,현민수,김성구 순천향의학연구소 2002 Journal of Soonchunhyang Medical Science Vol.8 No.1

Background and Objectives : Cigarette smoking is a major factor and the most modifiable risk factor for atherosclerosis. Endothelial dysfunction is an early event in atherosclerosis, before the structural change of the systemic arteries. We hypothesized that endothelial dysfunction might be present in the systemic arteries of young adult smokers and that this might be dose-dependent phenomenon. Therefore, we try to certify that smoking is associated with endothelial dysfunction in healthy young adults without other risk factor of atherosclerosis. Subjects and Methods : we studied noninvasively 29 subjects aged 3 to 4 decades without other risk factor of atherosclerosis, they were composed of the two groups, current smokers(n=15) and nonsmokers(n=14). Smoking history varied from 3 to 20 pack years. Using high-resolution ultrasound, vessel diameter and mean flow rate were measured at rest, during reactive hyperemia(with flow-mediated endothelium-dependent dilation), and after sublingual nitroglycerin(NG-induced endothelium-independent vasodilation). Result : Flow mediated endothelium dependent dilation was observed in the control subjects (9.4±3.44%) but was impaired in the smokers(5.8±2.51%)(p=0.004). NG-induced endothelium independent dilation is no difference in all subjects. Conclusion : Cigarette smoking is associated with endothelial dysfunction in healthy young adults.

수학자 이상설이 소개한 근대자연과학: <식물학(植物學)>

박영민 ( Young Min Park ),김채식 ( Chae Sik Kim ),이상구 ( Sang Gu Lee ),이재화 ( Jae Hwa Lee ) 한국수학교육학회 2011 수학교육논문집 Vol.25 No.2

본 원고는 2004년 과학사학자 박성래 교수가 독립 운동가이자 한국 근대 수학교육의 아버지로 부르기 시작한 보재 이상설(李相卨, 1870-1917)이 자연과학에 기여한 내용을 다루고 있다. 한국수학사학회지 2009년 11월 호에 자세히 소개된 〈數理〉를 쓴 시기를 전후하여, 같은 시기에 이상설이 붓으로 쓴 것으로 여겨지는 〈植物學>(이상설, 1899)은 총 4면의 초록 필사본이며, 그 대본(臺本)은 〈植物學啓蒙〉 (Edkins, 1886)으로 영국의 Joseph Edkins(艾約瑟, 1823-1905)가 번역하여 1886년에 간행한 〈西學啓蒙〉 16종 가운데 하나이다. 이상설의 〈植物學>은 이 〈植物學啓蒙〉을 읽으면서 그 책의 내용 중 당시의 조 선 학자가 모르고 있던 새로운 내용을 중심으로 메모를 한 것으로 여겨진다. 본 연구에서는 전통산학과 근대서양수학을 연결하는 〈數理〉를 저술했으며. 우리나라의 정규 교과과정에 수학과 과학을 필수과목으로 지정하고, 첫 번째 수학교과서 〈산術新書〉를 발간함으로 당대 최고의 수학자로 평가된 이상설이 쓴 〈植物學〉을 발굴하여 그 내용과 의미를 최초로 분석한다, 이를 통하여 당시 조선의 서양 과학, 특히 식물학에 대한 이해 수준을 분석하고 〈植物學〉의 원전인 〈植物學啓蒙〉 과 <西學啓蒙〉의 저자에 대하여 알아본다. 이는 당시 수학교육자가 자연과학분야에 행한 교육적 기여를 이해 하는데 필수적인 연구이다. This paper deals with contents that Sang-Seol Lee contributed to the natural science in the 19th century Korea. Prof. Sung-Rae Park, the science historian, called Sang-Seol Lee Father of the Modern Mathematics education of Korea. Sang-Seol Lee wrote a manuscript Botany with a brush in late 19th century. Botany was transcribed from Science Primers: Botany (written by J. D. Hooker), which is translated into Chinese by Joseph Edkins in 1886. The existence of Sang-Seol Lee`s book Botany was not known to Korean scientists before. In this paper, we study the contents of Botany and its original text. Also we analyze people`s level of understanding Western sciences, especially botany at that time. In addition, we study authors of 16 Primers for Western Knowledge. We study the contribution of mathematician Sang-Seol Lee to science education in the 19th century Korea.

연령집단에 따른 노인의 허약(Frailty) 예측요인 분석

조성은 ( Cho Sung Eun ),최은영 ( Choi Eun Young ),오영삼 ( Oh Young Sam ),김영선 ( Kim Young Sun ),김성복 ( Kim Seong Bok ) 한국보건사회연구원 2017 保健社會硏究 Vol.37 No.3

This study aims to investigate the predictors of frailty in different age groups. To address this purpose, this study used the 2014 Survey of the Living Conditions of the Elderly (SLCE). In the research model, 4,123 older adults aged 75 and older were included from the SLCE. All participants were subdivided into two age groups based on their age; the young old group (75-85) and the old-old group (85+). The young old group consisted of 1,453 (43%) pre-frail older adults and 1,268 (37%) frail older adults; the old-old group consisted of 304 (40%) pre-frail older adults and 396 (52%) frail older adults. Our regression analysis showed that in the young-old, being female, lower levels of education, having more chronic diseases, having fall experience, higher depression, lower cognitive functioning significantly predicted transition to pre-frailty from non-frail status. In the old-old, being female, higher depression, lower level of social activity were significant predictors. On the other hand, predictors of transition to frailty from pre-frail status in the young-old were being female, higher age, being unemployed, having more chronic diseases, having fall experience, higher depression, lower cognitive functioning. In the old-old, predictors of transition to frailty from pre-frail status were only higher age, having more chronic disease, higher depression, and lower cognitive functioning. The research findings can be used as a reference point in the making of strategies for preventing frailty.

40세 이하 관상동맥 질환자에서 장기적 임상 관찰

이승욱,정명호,박종철,박형욱,조상희,김원,김계훈,이상현,강경태,조장현,김남호,김건형,안영근,조정관,박종춘,강정채 全南大醫大 2001 전남의대학술지 Vol.37 No.2

노년기 주관적 연령과 건강노화와의 관계: 연령집단별 분석

최은영 ( Choi Eun Young ),조성은 ( Cho Sung Eun ),오영삼 ( Oh Young Sam ),장희수 ( Chang Hee Su ),김영선 ( Kim Young Sun ) 한국보건사회연구원 2017 保健社會硏究 Vol.37 No.1

The purpose of this study is to examine the relationship between subjective age (whether one subjectively perceives himself as `the elderly` or `not the elderly`) and healthy aging. Using data from the 2014 National Elderly Survey (KIHASA), this study selected a total of 9,653 participants consisting of young-olds (aged 65-74) and old-olds (aged 75-84) For both the young-old and the old-old, multiple regression analyses were conducted to examine the research model. In the young-old population, one`s considering oneself as “non-elderly” was significantly associated with higher cognitive functioning, fewer chronic diseases, lower depressive symptoms, and higher level of social engagement. On the other hand, in the old-old population, one`s considering oneself as “non-elderly” was associated only with higher cognitive functioning, and not with the other domains of healthy aging. The findings suggest that subjective age can be considered as an important predictors of older adults` healthy aging. These findings indicate that the association between subjective age and healthy aging has a different pattern depending on the age group.

노화에 따른 골격근에서 운동훈련에 의한 자식작용 반응

Yong An Kim(김용안),Young Sang Kim(김영상) 한국생명과학회 2011 생명과학회지 Vol.21 No.3

Autophagy는 항상성 유지와 스트레스반응을 효율적으로 조정하기 위해 필수적인 세포 내 질적 조절작용이다. 노화가 진행되는 동안 autopahgy에 의한 degradation 효율성 저하와 그로 인한 세포 내 부산물의 축적이 증가하여 결국, 근육의 약화를 초래한다. 그러므로 본 연구의 목적은 골격근에서 운동에 의한 autopahgy 관련 단백질의 변화를 규명하는데 있다. 이를 위해 24마리의 Young 그룹과 Old 그룹을 나누어 각각 대조군(n=6)과 운동군(n=6)으로 배정하였다. 운동은 8주간 주 5회 실시하였고, 트레드밀 속도 16.4 m/min와 경사도 4%로 설정하여 40분간 지속적인 운동을 실시하였다. autopahgy 관련 단백질에 대한 검증 결과 Young 그룹과 비교하여 Old 그룹에서 LC3-1, Beclin-1, Atg7은 모두 유의하게 감소하였다. 그러나 8주간의 규칙적인 운동에 의하여 autophagy 관련 단백질은 증가하는 것으로 나타났다. 따라서 노화에 의해 약화된 autopahgy 기능은 규칙적인 운동에 의해 개선될 수 있을 것으로 사료된다. Autophagy, a highly conserved mechanism of internal quality control, is essential for the maintenance of cellular homeostasis and for the orchestration of an efficient cellular response to stress. During aging, the efficiency of autophagic degradation declines and intracellular waste products accumulate. Therefore, the aim of this study is to investigate the effects of exercise on autophagic response in skeletal muscle. Twenty-four Young (4 month) and Old (12 month) ICR-type white male mice were divided into a control group (CON: n=6) and exercise training group (Tr: n=6) after an adaptation period of 1 week. Exercise consisted of treadmill running at 16.4 m/min with a 4% incline, 40 min/day and 5 days/week for 8 weeks. Cervical dislocation was performed at 48 hours after the last round of exercise, after which the gastrocnemius skeletal muscle were immediately collected. The results of verifying autophagy formation showed that the Sarcopenia index was decreased in the Old mice compared to the Young. However, it increased with exercise training in the Old. Lipidation LC3-Ⅱ, Becline-1, and Atg7 were decreased in the Old mice compared to the Young. However, Lipidation LC3-Ⅱ was significantly increased in the trained Old mice (Young:1 Vs Old:1.32±0.042, p<0.05). Based on these data, we suggest that autophagy regulatory events are the attenuated in Old mice, but that they are enhanced with exercise training.

Comparison of trophic factors changes in the hippocampal CA1 region between the young and adult gerbil induced by transient cerebral ischemia.

Yan, Bing Chun,Park, Joon Ha,Kim, Sung Koo,Choi, Jung Hoon,Lee, Choong Hyun,Yoo, Ki-Yeon,Kwon, Young-Geun,Kim, Young-Myeong,Kim, Jong-Dai,Won, Moo-Ho Kluwer Academic/Plenum Publishers 2012 Cellular and molecular neurobiology Vol.32 No.8

<P>In the present study, we investigated neuronal death/damage in the gerbil hippocampal CA1 region (CA1) and compared changes in some trophic factors, such as brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF) and vascular endothelial growth factor (VEGF), in the CA1 between the adult and young gerbils after 5 min of transient cerebral ischemia. Most of pyramidal neurons (89%) were damaged 4 days after ischemia-reperfusion (I-R) in the adult; however, in the young, about 59% of pyramidal neurons were damaged 7 days after I-R. The immunoreactivity and levels of BDNF and VEGF, not GDNF, in the CA1 of the normal young were lower than those in the normal adult. Four days after I-R in the adult group, the immunoreactivity and levels of BDNF and VEGF were distinctively decreased, and the immunoreactivity and level of GDNF were increased. However, in the young group, all of their immunoreactivities and levels were much higher than those in the normal young group. From 7 days after I-R, all the immunoreactivities and levels were apparently decreased compared to those of the normal adult and young. In brief, we confirmed our recent finding: more delayed and less neuronal death occurred in the young following I-R, and we newly found that the immunoreactivities of trophic factors, such as BDNF, GDNF, and VEGF, in the stratum pyramidale of the CA1 in the young gerbil were much higher than those in the adult gerbil 4 days after transient cerebral ischemia.</P>

어머니의 전통적 가치관과 자녀의 인성 특성에 관한 연구

성영혜,윤지영 숙명여자대학교 아동연구소 2000 兒童硏究 Vol.14 No.1

The purpose of this study was to investigate the relation between the traditional sense of values of mothers and personality of children on the hypothesis of that the former would influence the later. The detail Purposes of this study are: 1. Does the traditional sense of values of mothers differs in terms of some selected variables(age, education, income, residence, family structure)? 2. What relation does the traditional sense of values of mothers have with the personality of children(female or male)? 3. How do the relations between the traditional sense of values of mothers and the personality of children differ in terms of family structure(extended or nuclear family)? The subjects for this study were students and their mothers of 3 elementary schools located in Seoul(the detail location of the schools are in Kang-Nam Gu, in Kang-Buk Gu, and in Kang-Dong Gu) and 1 elementary school located in Yeosu. The research data in this study was collected from 187 children(and their mother) in Seoul and 199 children(and their mother) in Yeosu. This study used value-oriented scale made by Lim, Hee-seop(1994) to measure the traditional sense of values of mothers, and personality test for elementary school made by Jung, Beom-mo to measure personality of children. The data was processed and analysed through the statistical methods(SAS computer program), t-test, on-way Anova, and Multiple Regression(Stepwise). The major findings of this study are as follows. First, in the research to find out the difference of the traditional sense of values in terms of family conditions, authoritarianism had significant difference when residence, father's age. Mother's education level change. In other words, the authoritarianism was stronger the more the father was old, the less the mother was educated. And the authoritarianism was stronger in the country. Familism had significant difference when residence, education level of stronger the less the mother and father were educated, the less the income was. And the authoritarianism was stronger in the country. Humanism had significant difference when education level of mothers, income level changed. In other words, humanism was stronger the more the mother was educated, the more the income was. Second, in the research to find out the traditional sense of values of mother which explains the personality of children best in terms of sex of the children, the familism explains the reflectiveness of male children best, and the humanism explained the emotional stability of male children best. And for the female children, the authoritarianism of mother was found out to be the most provable explanative variables which explained the impulsiveness of female children best. Third, in the research to find out the traditional sense of values of mother which explains the personality of children best in terms of the family structure, when it was extended family the authoritarianism was found out to be the explanative variable for the impulsiveness of children. And when it was found to be the explanative variable for the impulsiveness of children. And when it was nuclear family, in the research to find out the traditional sense of values of mother which explains the personality of children best, the authoritarianism was found to be the explanative variable for the dominance and reflectiveness of children.

구강으로 돌출한 선천성 두개내 기형종 -1 부검례-

김영실,이교영,강창석,심상민,김선무 대한병리학회 1990 Journal of Pathology and Translational Medicine Vol.24 No.3