• 한국정밀공학회지
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• 제15권4호
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• pp.51-57
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• 1998

It is common to assume identical allowable safety factors in static strength defined by mean stress and in fatigue, defined by stress amplitude. Under the load with asymmetrical cycles the safety factor is not the same. In this paper, with the consideration of unequal allowable safety (actors a general method for estimating fatigue reliability of a machine element under a combined state of stress is derived based on the theory proposed by Prof. Kececioglu and a normal distribution. The calculation of fatigue reliability fur limited life is discussed with example.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2005년도 추계학술대회 논문집
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• pp.17-22
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• 2005

An experimental study was carried out to investigate the effect of local ultrasonic forcing on a turbulent boundary layer. Stereoscopic particle image velocimetry (SPIV) was used to probe the characteristics of the flow. A ultrasonic forcing system was made by adhering six ultrasonic transducers to the local flat plate. Cavitation which generates uncountable minute air-bubbles having fast wall normal velocity occurs when ultrasonic was projected into water. The SPIV results showed that the wall normal mean velocity is increased in a boundary layer dramatically and the streamwise mean velocity is reduced. The skin friction coefficient ($C_{f}$) decreases $60\%$ and gradually recovers at the downstream. The ultrasonic forcing reduces wall-region streamwise turbulent intensity, however, streamwise turbulent intensity is increased away from the wall. Wall-normal turbulent intensity is almost the same near the wall but it increases away from the wall, In tile vicinity of the wall, Reynold shear stress, sweep strength and production of turbulent kinetic energy were decreased. This suggests that the streamwise vortical structures are lifted by ultrasonic forcing and then skin friction is reduced.

• 한국가스학회지
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• 제1권1호
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• pp.21-26
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• 1997

본 논문에서는 비선형 유한요소해석 프로그램을 이용하여 초저온 액체에 의한 정압과 열하중을 받는 멤브레인 구조물의 응력기동과 응력수준을 6가지 주름모델에 대한 수치적 해석결과를 제시하였다. 맴브레인 판재의 상면을 따라 최대 평균법선 응력분포에 관한 여러 가지 기하학적 주름의 3차원 해석을 수행하였고, 이들 주름형상에 대한 유한요소해석 결과를 비교$\cdot$고찰하였다. 링 마디식 모델의 주름 형상은 작은 코너반경과 정점곡률을 갖는 테크니가즈식 주름에 비하여 효과적으로 거동하고 있음을 보여주고 있다. 유한요소해석 결과예 의하면 LNG 저장탱크에 이들 모델을 사용할 경우 링 마디식 주름이 여타 주름 모델에 비하여 가장 깊은 180m에서도 사용될 수 있음을 보여준다.

• 동의신경정신과학회지
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• 제18권1호
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• pp.123-132
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• 2007

Objective : The purpose of this research is to investigate the effects of Autogenic Training on autonomic nervous system for normal subjects with Heart Rate Variability(HRV). Then HRV of total subjects were analyzed by Sasang constitution, MBTI type and relaxation therapy experience. Method : Autogenic Training was applied on 39 subjects individually. Then HRV was examined each 5 minutes before and after Autogenic Training application. Results : 1. Mean HRV, SDNN, SDSD were significant different in HRV between before and after Autogenic Training application in total subjects. 2. SDNN, SDSD were significant different in HRV between before and after Autogenic Training application in Soeumin. Mean HRV, SDNN, SDSD were significant different in HRV between before and after Autogenic Training application in Taeeumin. Conclusion : The results suggest that Autogenic Training application have shown anti-stress effects. Autogenic Training application to Soeumin and Taeeumin have shown more anti -stress effects than application to Soyangin.

• 대한한방소아과학회지
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• 제21권2호
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• pp.1-12
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• 2007

Objectives : Allergic children have known to have multiple behavior problems. Among them, attentional ability disorder is one of the most common problems. This study is to examine relationship between learning ability and allergic rhinitis by analyzing EEG status of children. Methods : We analyzed cognitive functions of two different children groups; 21 children with allergic rhinitis and 19 normal children with CANS 3000(Central & Autonomic Nervous System, LAXTHA Inc., Korea), cognitive functions assessment program by EEG. Results : 1. According to mean active EEG rhythm of Theta, Alpha, SMR, M-beta, there were no significant difference between allergic rhinitis and the normal group. 2. According to mean active EEG rhythm of right H-beta, Gamma wave allergic rhinitis group's value was significantly higher than that of the normal group. 3. According to mean cognitive strength, response, concentration, left / right brain activity and learning ability score, there were no significant difference between allergic rhinitis and the normal group. 4. According to mean workload score, allergic rhinitis group's value was significantly higher than that of the normal group. Conclusions : It is likely that allergic rhinitis group, which showed relatively high frequency EEG rhythm, is more fragile to stress and less active on mental processing. Along side with physical examination, psychological assessment should also be conjugated on treating children with allergic rhinitis.

• 한국임상약학회지
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• 제21권2호
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• pp.131-137
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• 2011

The purpose of this study was to evaluate the clinical efficacy of a standardized special ethanol extract from Gynostemma pentaphyllum as a management for anxiety and stress of normal population. This is a two-arm, parallelgroup, randomized, double blind clinical trial comparing Gynostemma pentaphyllum extract 200 mg bid (GP-EX, n=48) or placebo bid (n=54). The main outcome measures were the decrease in anxiety sensitivity index (ASI), the State version (S-STAI) of the Stait-Trait Anxiety Inventory (STAI) and the Trait version (T-STAT) of the STAI from baseline over a 6 weeks treatment period. In more anxious group (S-STAI50 or ASI19), the anxiety in group with GP-EX was decreased significantly than one in normal population with placebo [S-STAI50: T-STAI = from $57.7{\pm}6.5$ ($mean{\pm}S.D.$) to $46.8{\pm}11.2$ in normal population with GP-EX, p=0.002 vs. from $54.1{\pm}9.9$ to $49.0{\pm}9.6$ in normal population with placebo, p>0.05; ASI19: T-STAI = from $47.2{\pm}12.0$ to $42.4{\pm}11.1$ in normal population with GP-EX, p=0.022 vs. from $48.7{\pm}11.5$ to $46.0{\pm}10.4$ in normal population with placebo, p>0.05]. The most frequently reported adverse reactions considered possibly related to treatment were mild gastrointestinal events. GP-EX is more effective than placebo and is well tolerated as a therapy for anxiety and stress of normal population.

• 동의신경정신과학회지
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• 제17권3호
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• pp.57-65
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• 2006

Objectives: The purpose of this research is to investigate the effects of Benson's Relaxation Technique on autonomic nervous system for normal subjects with Heart Rate Variability(HRV) and find out relationship with anti - stress effects. Methods: First, Benson's Relaxation Technique was applied on 5 normal subjects for three weeks. Then HRV was examined for 15 minutes Benson's Relaxation Technique application. Next, Benson's Relaxation Technique each 8 times was applied on 5 normal subjects for 1 weeks. Then :HRV was examined each 5 minutes before and after Benson's Relaxation Technique application. Results: 1. SDNN, SDSD increased continuously in HRV for three weeks Benson's Relaxation Technique application. 2. Mean HRV, SDNN, SDSD were significant different in HRV between before and after Benson's Relaxation Technique application at fourth week. Conclusion: The results suggest that Benson's Relaxation Technique application have shown anti-stress effects and the more Benson's Relaxation Technique is repeated, the more effective.

• 한국지반공학회논문집
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• 제36권12호
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• pp.117-124
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• 2020

본 연구는 온도에 따른 점성토의 전단 변형의 특성의 모사에 초점을 맞춘다. 일반적으로 온도가 상승할수록 정규압밀선은 간극비와 평균유효응력의 평면에서 하향 이동한다. 하지만 한계상태선은 온도변화에 따라 정규압밀선만큼 이동하지는 않는다. 따라서, 온도가 증가할수록, 한계상태 평균유효응력과 선행압밀 평균유효응력의 차이는 감소한다. 이를 반영하기 위해, 본 연구에서는 한계상태 평균유효응력을 기준으로 두 부분으로 나뉘어진 경계면을 적용하였다. 또한 Bangkok 점성토에 대해서 경계면을 구축하고, 비배수 삼축압축시험에 대해서 요소해석을 실시하였다. 요소해석 결과, 제안된 모델은 복잡한 강성 혹은 발달 법칙 없이 실험 데이터와 유사한 점성토의 온도에 따른 역학적 거동을 잘 모사하였다.

• 정신신체의학
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• 제6권1호
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• pp.3-12
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• 1998

Objective : The sensation of dysphagia, heartburn, globus hystericus, and functional dyspepsia are common symptoms of the functional upper gut disorders. This study was designed to investigate quantity of perceived stress, depression, and anxiety in the patients with functional upper gut symptoms whose esopahgeal manometry(EM) and gatroesophageal reflux (GERT) test were normal. Methods : A total of 38 patients who complained of the symptoms had been tested with 24-hour ambulatory EM and conventional GERT in our gastrointestinal clinic. Thirty patients whose tests had been normal(patients group) were assessed with Symptom Checklist-90-Revision(SCL-90-R), Beck Depression Inventory(BDI), and Spielberger Stait-Trait Anxiety Inventory(STAI) and compared with 30 patients(control group) without functional upper gut symtpoms in the hepatobiliary clinic. The two groups were also assessed by quantity of perceived stress during the last year through self-report. Results: 1) These patients tended to be predominently female, older, and possessed a lower education than control group. 79% of 38 patients who had been tested were normal. 2) Compared to the control group, the patients had significantly higher mean scores on four subscales(somatization, depression, anxiety, and positive symptom distress index). 3) The patient group had significantly more perceived stress than the control group. 4) The patients group had significantly higher levels of depression than the control gorup, but there was not any significant difference in the STAI. 5) There were significant positive correlations between the BDI score and the STAI-trait, the STAI-stait and the STAI-trait, the quantity of perceived stress and the STAI-trait. Conlusion : The patients with functional upper gut symptoms displayed more, psychological distress, sornatization, anxiety, and deperssion. Among them, patients had higer depression than control group. Functional upper gut symtoms could be more appropriately viewed as somatic symptoms of depression. These findings suggest that such patients need to have psychiatric intervention and treatment.

• 대한한방부인과학회지
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• 제24권3호
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• pp.85-97
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• 2011

Objectives: Oligomenorrhea is clinically important because it can be progressed to amenorrhea. The purpose of this study is to analyse the characters of oligomenorrheic patients by comparison normal menstrual cycle group and oligomenorrheic group of BMI, Yangdorak, menarche. Methods: We studied 58 patients visiting $\bigcirc\;\bigcirc$ Medical Center from May 1st, 2010 to April 30th, 2011. 29 oligomenorrheic group and 29 normal menstrual cycle group were compared with BMI, Yangdorak, menarche. The SPSS 12.0 for windows was used to analyse the data. Results: Mean BMI of oligomenorrheic group was lower than normal menstrual cycle group and statistically significant. Mean H1, H2, H3, H4, H5, H6 of oligomenorrheic group was lower than normal menstrual cycle group and statistically significant. Mean menarche of oligomenorrheic group was lower than normal menstrual cycle group, but there was no statistical significance. Conclusions: The results suggest that diagnosis of oligomenorrheic patients by stress would be useful Yangdorak.