양방향 요소제거법을 이용한 신뢰성 기반 최적설계

유진식,박재용,황승민,임민규,오영규,한석영 한국공작기계학회 2008 한국공작기계학회 추계학술대회논문집 Vol.2008 No.-

This research presents a Reliability-Based Topology Optimization (RBTO) using Bi-directional Evolutionary Structural Optimization (BESO). An actual design involves uncertain conditions such as material property, operational load and dimensional variation. Deterministic Topology Optimization (DTO) is obtained without considering of uncertainties related to the uncertainty parameters. However, RBTO involves evaluation of probabilistic constraints, which can be done in two different ways, the reliability index approach (RIA) and the performance measure approach (PMA). The reliability index approach (RIA) and the performance measure approach (PMA) are adopted to evaluate the probabilistic constraints. In order to apply the BESO method to the RBTO, sensitivity number is defined as the change in the reliability index due to the addition or the removal of the ith element. In the BESO, a mesh-independency filter using nodal variables is used to remove the checkerboard patterns. The optimal topologies of RIA and PMA are obtained very similarly. It is shown that RBTO based on BESO can be effectively applied from the presented examples.

청소년자원봉사자의 효율적인 관리방안에 대한 연구

유승엽,이영주 남서울대학교 2004 남서울대학교 논문집 Vol.10 No.3

The purpose of this study is to analyze the volunteer activities of the youth. Todays society has an increasing demand and necessity for voluntary service, youth volunteer activities which have become a major social educational issue. These activities were expected to contribute to increase of public benefits and rebuilding of community as well as ego-realization and promotion of social mind of the youth. Thus in order to activate the youth volunteer activities, it is necessary to understanding, education and evaluation of youth volunteer activities.

강자성체에서 상전이의 수치적 모의실험

유대영,양해정,양회룡,정진,최승평,장차익 조선대학교 기초과학연구소 2001 自然科學硏究 Vol.24 No.-

It is difficult to explain the magnetic phase transition with classical physics in Curie temperature. We studied qualitatively with the well known Ising model in statistical mechanics. We simulated systems of finite size by Monte Carlo methods with Metropolis algorithm. Thus we could estimate the values of quantities such as the magnetization(m) per spin the specific heat(c) per spin the magnetic susceptibility(χ) per spin, and the mean energy per spin compare with the numerical values in infinitive size. The quantities of c, m, χ, e varied rapidly within 2.3∼2.4 temperature at J/k units. Those values show that the critical temperature can be within the range. The hysteresis loop was obtained with this model.

자일리톨과 불화나트륨을 함유한 저작성 정제가 교정환자의 구강위생에 미치는 영향에 관한 임상시험

유상훈,안석준,이신재,백승학,김태우,장영일,남동석 대한치과교정학회 2003 대한치과교정학회지 Vol.33 No.2

본 연구는 불화나트륨과 자일리톨 성분으로 구성된 구강 청정용 저작성 정제(덴포정, 하미즐, 부천, 경기)가 교정치료 중인 환자의 구강위생 상태에 미치는 영향을 알아보기 위해 시행되었다. 교정치료 중인 18세 이상의 성인 환자 30명을 대상으로 약제 상요 전, 2주 후, 4주 후에 피험자의 상악과 하악 전치 부위 및 구치 부위에서 각각 치은 지수, 치은 출혈 지수, 치태 지수를 측정하여 다음과 같은 결과를 얻었다. 1. 상하악 전치부와 구치부 모두에서 치태 지수가 약제 사용 전에 비해 사용 2주 후와 4주 후 유의성 있게 감소하였다(p<0.05). 또한, 적용 2주 후와 4주 후의 지수를 비교하였을 때 4주 후에 좀 더 개선된 경향을 보였으나, 통계적 유의성은 나타나지 않았다(p<0.05). 2. 치은 지수, 치은 출혈 지수도 상하악 전치부와 구치부 모두에서 적용 전에 비하여 2주 후와 4주 후 유의성 있게 감소하였다(p<0.05). 적용 2주 후와 4주 후의 지수의 비교 검증에서 통계학적으로 유의할 만한 차이가 보이지 않아 구강위생 상태의 개선이 계속 유지됨을 보였다. 본 연구의 결과는 치태 지수, 치은 지수, 치은 출혈 지수가 실험 정제 적용 후에 감소하여 구강위생 상태가 개선되었음을 보였다. 이러한 결과를 통해 덴포정을 교정치료 중인 환자에서 부가적으로 사용하였을 경우 치주조직의 건강을 증진시키는데 도움을 줄 수 있으리라고 생각된다. The aim of this study was to evaluate the effect a chewable tablet containing sodium fluoride and xylitol (DenPo, Hamizzle, Bucheon, Kyungki) on the oral hygiene state in the orthodontic patients. The subjects consisted of 30 adult orthodontic patients, who have worn the fixed orthodontic appliance at least 6 months. They were instructed to use the tablet forth a day. Gingival index (GI), plaque index (PI), and sulcus bleeding index (SBI) of upper and lower anterior and posterior regions were measured before using the tablet (TO), 2 weeks after using the tablet (T1), and 4 weeks after using the tablet (T2). The data were analyzed with Wilcoxon signed ranks tests. The results were as follows ; 1. PI was decreased significantly in the T1 and T2 stage compared with TO stage in the both anterior and posterior regions (p<0.05). Although PI was decreased in the T2 stage compared with T1, there was not statistical significance(p>0.05). 2. GI and SBI showed similar results compared with PL. In the T1 and T2 stage, there was statistically significant decrease in the GI and SBI (p<0.05). This study showed that the DenPo tablet could be used as an adjunct to improve oral hygiene in the orthodontic patients. The decrease of the indices may suggest that DenPo tablet could be effective in the plaque removal and prevention of gingival inflammation in the orthodontic patients.

국제 인적자원관리 전략의 결정요인과 성과 : 한국내 외국인기업을 중심으로

유승훈,윤영득,김종관,김영근 대한경영학회 2003 大韓經營學會誌 Vol.16 No.7

This study explores how the tension between global integration and local responsiveness affects the dimensions and determinants of international human resource strategy. The effects of interorganizational interdependencies, competitive strategies and cultural differences, ownership on the two different dimensions of IHR strategy were studied using a sample of 53 MNCs subsidiaries operating in Korea. The findings for global integration suggest that when a subsidiary is highly dependent on the parent to provide crucial resources. And the findings for local responsiveness suggest that when a subsidiary is highly dependent on the host to provide crucial resources and institution. As for the hypothesized interaction shows a negative, significant relationship between a subsidiary's dependence on host institution and ownership and its localization(b=0.0211, p=0.05). Also between a subsidiary's dependence on host resource and ownership and its localization(b=-0.0113, p=0.1). Accordingly, these insights should prove to be useful to researchers and international human resource managers interested in the formulation and implementation of international human resource strategies.

휴리스틱 체계적 모델을 통한 관광행동의 이해

유진선,이승영 경기대학교 관광종합연구소 2015 여가관광연구 Vol.23 No.-

This paper aims to introduce the heuristic systematic mode and propose some implications that should be actively utilized in understanding tourist behavior. Heuristic systematic model is a theory that drawing conclusions through an intuitive way of thinking , rather than in the absence of a clear clue status on the basis of reasonable thinking. In everyday situations, we have many cases that the decision through an intuitive way of thinking than rational thinking through a decision . Tourist behavior in many cases decisions through intuitive thinking like this. But look came ahead of the leading tourism research through action research to understand the rational way of thinking is understood to consist of continuous action by the irrational mindset is not carried. In other words, in order to understand the irrational behavior by thinking in understanding the tourism action it should be to understand the heuristic systematic model prior , and should use them actively to understand the tourism behavior.

Supra Pubic Catheter를 施行한 腦卒中 患者 1例에 對한 證例報告

유병찬,오병렬,김민상,안정조,임승민,최영,설인찬 대전대학교 한방병원 2002 惠和醫學 Vol.11 No.1

According to the literary study on catheterization of bladder in one case of patient with C.V.A. who was treated by supra pubic catheterization, the results were as follows. 1. If not immediately treat ischuria, emergency disease, very great danger to life can happen by loss of kidney function. So we must treat ischuria instantly by consideration of treatment from the factor. 2. Catheterization of bladder generally acted in emergency room, is emergency treatment only in the lower part of urethral obstruction. 3. Catheterization of bladder was put on record in Son Saimiao's Qianjinyaofang, which is the first book on it. It had been developed by Luo Qianyi, Zhang Jiepin, and Wang Dao. 4. Ancient times, an urethral catheter was made of green onion leaf, pig bladder, goose feather and so on. 5. Nelaton is catheterization of bladder in functional or momentary ischuria. Indwelling catheterization is treatment keeping in urethral canal for a long time. 6. Supra pubic catheterization is a surgical operating catheterization when urethral catheterization is impossible, is very easy and can decrease risk of infection. 7. After catheterization, for decreasing risk of the infection, a complication of catheterization, it is must be taken precedence, ascetic treatment, constantly management and sterilization, anti-biotic medication. 8. At times, increasing patient of emergency disease, as C.V.A etc., the needing of catheterization of bladder is increasing also for preventing infection and bed sore by ischuria and incontinence of urine. Therefore a specialty knowledge and skill about it is necessary.

제2형 당뇨병 동물모델인 OLETF 쥐에서 장기간 라미프릴 투여가 내당능 및 췌도 베타세포에 미치는 효과

고승현,윤건호,김명미,안유배,송기호,유순집,손현식,차봉연,이광우,손호영,강성구 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.25 No.6

연구배경:최근 소개된 HOPE(Heart Outcomes Prevention Evaluation)study의 결과에 의하면, 심혈관질환이나 이에 대한 위험인자가 1가지 이상인 9,541명을 대상으로 안지오텐신 전환효소 억제제의 일종인 라미프릴을 투여하여 사망율과 뇌졸증, 심부전, 당뇨병 합병증이 개선되었을 뿐 아니라 다른 항고혈압제에 비해 새롭게 당뇨병으로 진단되는 환자가 줄었음을 보고한바 있다. 이에 저자들은 라미프릴(ramipril)을 제2형 당뇨병 동물모델에 장기간 투여함으로써 당뇨병을 예방하거나 고혈당 상태 또는 인슐린 감수성을 개선시킬수 있는지를 알아보고자 하였다. 방법:생후 24주된 체중 400∼450g의 OLETF와 LETO 쥐를 대상으로 6개월간 라미프릴 경구투여 하였고 혈압, 24시간 단백뇨 및 인슐린 내성검사를 시행하였다. 6개월 이후로는 8주간 투여군과 대조군의 체중을 비슷하게 맞추어 내당능 상태를 평가하였고 이후 다시 8주간 고농도 포도당을 투여하였다. 경구당부하검사를 시행한 후 희생시켜 조직표본을 만들어 guinea pig anti­human insulin 항체로 염색후 DAB로 발색하여 point count 법으로 베타세포를 정량하였고, 면역염색으로 췌도의 변화와 섬유화의 정도를 관찰하였다. 결과:라미프릴을 6개월간 투여하였을 때 OLETF 쥐에서 1)체중 증가가 적었으며 2)경구 당부하검사시 포도당하 면적은 의미있게 감소하였고 3)인슐린 내성검사상 Kitt가 증가되는 경향을 보였으며 4)수축기, 이완기 혈압과 24시간 단백뇨양이 의미있게 감소하였고 5)체중을 맞추면 내당능 상태가 비슷해졌다가 고농도 포도당 주입시 다시 포도당하 면적이 대조군에서 더 증가되었다. 라미프릴 투여군에서 췌도변형 및 파괴와 탈과립, 췌도내 섬유화가 감소하였다. 결론:본 실험에서는 인슐린 비의존성 당뇨병 동물 모델인 OLETF 쥐에서 당뇨병 발생 이전 단계부터 장기간 라미프릴을 투여할 경우 체중증가가 적었고, 투여군과 대조군의 체중을 맞추었을 때는 내당능상태의 차이가 없아가 고혈당 투여시 다시 투여군과 대조군에서 의미있는 차이를 보였다. 라미프릴 투여가 베타세포의 기능면에서 이로운 효과를 보일 것으로 생각되었다. 따라서 비만한 환자에서 안지오텐신 전환효소 억제제의 장기투여는 단백뇨 감소, 혈압강하 효과 이외에 체중증가의 억제 및 당뇨병 발생을 억제할 가능성을 시사한다. Background : In a Heart Outcomes Prevention Evaluation HOPE study, ramipril, a long-acting angiotensin-converting enzyme (ACE) inhibitor, significantly reduced the death rates the number of myocardial infarctions, strokes, heart failure as well as the risk of complications related to diabetes and of diabetes itself. However, it is known that ACE inhibitors improve glucose tolerance or insulin sensitivity or reduce the incidence of diabetes. Methods : 24 week-old OLETF (Otsuka Long Evans Tokushima Fatty) rats weighing 400 ~ 450 g were used in this study. 4 groups of rats were examined in parallel for 40 weeks. The OLETF rats were randomized for treatment with an aqueous solution of ramipril (5 mg/Kg) daily [OL (RMP), n=10)] and with saline [OL (CON), n=10)]. The LETO rats were also randomized in the same was as the OLETF rats (LT(RMP), n=10, LT (CON), n=10). The blood glucose level, body weight, systolic and diastolic blood pressure was assessed every month. At 3 and 6 months, the 24hrs urinary protein concentration was measured, and as insulin tolerance test and oral glucose tolerance test were conducted in all experimental groups. After 6 months, the body·weight was matched for 2 months in each corresponding group. Subsequently, a 15% sucrose loading was done for 2 months. After the glucose tolerance test, the pancreas was excised and immuno histochemical staining was conducted for insulin to quantify the beta cell mass by a point-counting method. In addition, the islet morphology was evaluated in the pancreas. Results : Ramipril treatment for a period of 6 months improved the 2hr blood glucose level, the area under the glucose curve in the oral glucose tolerance test, insulin sensitivity in addition to lowering significantly systolic and diastolic blood pressure and 24hrs urinary protein level significantly in OLETF rats. Of note, a lower weight gain was observed in both the ramipril-treated animals at 6 months. After weight matching, the AUC g and 2hr blood glucose level values were similar between the corresponding groups, but a 15% sucrose loading worsened the AUC g value. Histologically, the islets were less disorganized and the extent of fibrosis was lower in the ramipril-treated OLETF rats in the trichrome stain. Conclusion : Long-term treatment of ramipril, a long acting angiotensin-converting enzyme inhibitor may be useful for suppressing weight gain and proteinuria in addition to having a protective effect on the islet to harmful stimuli such as hyperglycemia (J Kor Diabetes Asso 25:469~482, 2001).

筋小胞體의 ATPase Kinetics에 關한 硏究

朴映淳,李承兩,朴泰水,庾基洙,李 弘,金允坤 圓光大學校 1982 論文集 Vol.16 No.2

본 연구에서는 토끼 골격근 소포체에서 분리한 근소포체의 ATPase활성에 대한 일반적 특성과 수종의 2가 양이온(??)의 영향에 관한 연구를 하였다. ATPase활성과 Ca uptake에 미치는 2가 양이온의 저해 효과와 저해기작은 Dixon plot, Lineweaver-Burk plot, Hanes-Woolf plot, Woolf-Augustinsson-Hofstee plot, Eadie-Scatchard plot, Arrhenius plot등을 이용하여 분석하였으며 그 결과는 다음과 같다. 1. 근소포체의 ATPase는 ??과 ??의 존재하에서 활성화 되어지며 ??의 농도가 4mM일 때 ??의 최적 농도는 0.1mM이었다. 2. 근소포체의 ATPase는 ??-ATPase와 (??)-ATPase로 구성되어 있고 (??) - ATPase의 활성은 ??-ATPase의 활성보다 높았다. 3. ATPase의 활성화 에너지는 약 19Kcal/mol이었다. 4. ATPase 활성에 미치는 2가 양이온은 12.5㎛과 400㎛의 범위 내에서 이온 농도가 증가됨에 따라서 활성도는 점점 감소되었다. 5. ATPase활성율 50% 저해시키는데 2가 양이온의 농도는 Ki값과 같아서 ??, ??, ?? Pd ??에 대한 각각의 농도는 10㎛, 30㎛, 130㎛ 및 350㎛이었다. 특히 ??은 저 농도에서 (12.5-100㎛)는 활성제로, 고농도에서 (200-400㎛)는 저해제로 작용하는 것 같다. 6. 2가 양이온은 ATPase의 Km에는 변화를 주지 않으나 Vmax의 저하를 일으키는 것으로 보아 비경쟁 저해제임이 판정되었다. 7. 2가 양이온은 가역적 저해제임이 판명되었다. 8. Ca 吸收能에 대한 CuCl₂의 阻害는 50~500㎛의 CuCl₂농도에서 현저히 나타났으며 이 현상은 Ca 吸收能과 ATPase 活性과 밀접한 관계를 보여주는 것이다. General properties of the ATPase and the effects of the divalent cations (??) on the total ATPase activity of the fragmented sarcoplasmic reticulum (FSR) isolated from rabbit skeletal muscle were investigated in the present resent research. The inhibitory effect of divalent cations on the FSR ATPase activity and its mechanism were analyzed by various plots such as Dixon plot, Lineweaver-Burk plot, Hanes-woolf plot, Eadie-Scatchard plot and Arrhenius plot. The results obtained were as follows: 1. The FSR ATPase is activated by ?? and ??; the optimum concentration of is 0.1 mM in the presence of 4 mM MgCl₂. 2. The FSR ATPase could be distinguished as ??-ATPase and (??)-ATPase. The activity of (??)-ATPase predomiant over that of ??-ATPase. 3. The apparent energies of activation for total ATPase was approximately 19Kcal/mole. 4. The inhibitory effects of the divalent cations on the enzyme activity increased as the concentrations of the divalent cations increased in the concentrations between 12.5 and 400㎛. 5. Concentration of 50% inhibition for each divalent cation was almost identical with the inhibition constant (ki). The Ki's were 10,30,130, and 350㎛ for ??, ??, ??, and ??, respectively. ?? seemed to be anactivator at lower concentrations and an inhibior at higher concentratios. 6. The divalent cations did not change the Km but decreased the Vmax of the FRS ATPase, suggesting that they are noncompetitive inhibitors on the FSR ATPase. 7. The divalent cations were also found to be revesible inhibitors on the FSR ATPase. 8. The inhibitory effect of CuCl₂on a uptake increased as the concentration CuCl₂increased in the range between 50㎛.

Polaron Hopping in the K_(2)O · B_(2)O_(3) · V_(2)O_(5) Glasses

차유정,강재필,홍성덕,김복수,김영훈,서용문,송승기 명지대학교 자연과학연구소 2005 자연과학논문집 Vol.24 No.-

K_(2)O · B_(2)O_(3) · V_(2)O_(5) 계 유리의 조성비에 따른 밀도, 굴절율, 전이온도, 천이금속이온비율 등과 직류 전기 성질을 100~450K 온도영역에서 연구하였다. 실험결과를 비정질 반도체에 관한 전기전도에 대한 이론 모델을 이용하여 분석하였다. 고온 영역에서는 직류전도도의 온도 의존성을 Mott의 포논-도움껑충뛰기 전도모델로 분석할 수 있었다. 활성화에너지는 0.28~0.33 eV로 시료내 V_(2)O_(5) 의 양이 증가할수록 감소하는 경향을 보인다. 저온 영역에서 직류 전기전도도는 Mott의 가변거리 껑충뛰기(variable-range hopping)전기전도도와 잘 일치하며, N(E_(F))값은 국지화 상태에서와 같다. The dc conductivity of K_(2)O-B_(2)O_(3)-V_(2)O_(5) glasses has been investigated in the temperature range 100~450K and physical parameters such as density, refractive indices, glass transition temperature and fraction of reduced transition-metal ion, were observed for various compositions. The experimental results are analyzed with reference to theoretical models proposed for electrical conduction in amorphous semiconductors. The analysis shows that at high temperature region the temperature dependence of the dc conductivity is consistent with Mott's model of phonon-assisted hopping of small polarons. The values of activation energy are 0.28~0.33 eV and decrease with increasing V_(2)O_(5) content in the sample. The lowtemperature dc conductivity data can be well fitted to Mott's variable-range hopping conductivity and the values of N(E_(F)) are also reasonable for localized states.