• 한국지반신소재학회논문집
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• 제11권2호
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• pp.39-47
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• 2012

본 연구에서는 블록식 보강토옹벽에 적용이 가능한 띠형 섬유보강재에 대하여 대형인발시험을 수행하였으며, 시험결과를 바탕으로 지반 내에 포설된 보강재의 인장변형 및 유발인발력을 분석하였다. 또한 전체면적법과 유효면적법을 이용한 인발강도를 평가하였다. 최대인발력은 보강재 폭 및 수직응력 조건에 관계없이 끝단 인발변위가 15mm 이내에서 발현되었다. 그리고 보강재의 설치간격과 관계없이 인발력과 끝단 인발변위 관계에 의한 인발거동은 유사한 것으로 확인되었다. 띠형 섬유보강재의 인발에 의한 변형은 보강재의 폭과 관계없이 선단부에 집중되어 선단부분에서 큰 인발력이 유발된 것을 확인하였다. 이는 수직응력 조건에 따른 마찰저항 보강재의 결속력이 인발저항에 매우 큰 영향을 미치는 것을 의미한다. 따라서 띠형 섬유보강재는 인장특성이 고려된 유효길이에 따른 평가가 이루어져야 보다 합리적인 설계가 가능한 것으로 분석되었다.

• 대한지역사회영양학회지
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• 제18권6호
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• pp.599-610
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• 2013

This study was carried out to analyze the effect of a diet program for adult women on weight loss, BMI, eating habits, sleeping habits, health related indices. The subjects was 415 participants of the 10 weeks (20 time participation program). The data was collected by basic somatometry and HRV (Heart Rate Variability) / APG (Accelerated Plethysmograph) Analyzer. The average age, height, weight and BMI were 28.6 years, 162.1 cm, 62.8 kg and 23.9 $kg/m^2$, respectively. Their body types by BMI were under weight (1.2%), normal (45.8%), overweight (24.8%), mild obesity (22.7%) and obesity (5.5%). There were significant reductions of average weight (4.6 kg) and average BMI (1.75 $kg/m^2$) on the 10th week. There were positive changes in vascular age (50.4%), stress index (44.6%), fatigue index (43.9%), health index (54.5%) of the subjects during the program. There was a meaningful difference of the average variation for the vascular age, stress index, fatigue index, and health index between two groups; one improving the eating habit and the other did not (p<0.05), and also there was a meaningful difference of the average variation for the fatigue index in both groups improving the sleeping habit (p<0.05), but was not a meaningful difference of the average variation for the vascular age, stress index, and health index between two groups. There was a meaningful difference of the average variation for the vascular age, stress index, fatigue index, and health index between two groups improving both eating and sleeping habit (p<0.05). In conclusion, the weight loss program was effective on the weight loss and BMI reduction and health related indices.

• 대한의용생체공학회:의공학회지
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• 제29권5호
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• pp.400-407
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• 2008

A health index was proposed that evaluates personal health state from both measured physiological variables and survey questions. Four health indices were defined such as cardiovascular index, stress index, obesity index, and management index. The total health index was calculated by summing these four health indices. Physiological variables such as blood pressure, heart rate variability(HRV), accelerated photoplethysmograph(APG), and body fat percentage were non-invasively measured and a survey questionnaire that asks personal health state, exercise intensity, and food preference was developed. The suggested health index was applied to thirty eight persons including 30 patients and 8 normal persons with an average age of 51.8. The average health index was estimated to be 75.1 out of 100 points. Young age group(below 50) and men group showed higher health indices than the aged(over 50) and women groups. The correlation coefficient between the cardiovascular index and stress index was found to be 0.513, which means stress is related to cardiovascular health state. The correlation coefficient between the measurements and survey questions was 0.385 for the cardiovascular index. It was as low as 0.182 for the stress index. More case studies may improve correlations between measurements and survey questions, and then, the current health index system may develop as an effective tool to evaluate personal health state.

• Journal of Acupuncture Research
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• 제32권1호
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• pp.1-11
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• 2015

Objectives : This study was performed to inquire into the protective effects of acupuncture on oxidative stress caused by cadmium accumulation in the kidney. Methods : Sprague-Dawley male($150{\pm}30g$) rats were stabilized for 1 week and divided into 5 groups: normal, control, $LR_3$ acupuncture, $BL_{23}$ acupuncture and sham acupuncture. For three days experimental groups received oral doses of cadmium 2 mg/kg twice a day. Acupuncture was applied bilaterally at each point 10 times for two weeks. The depth of stimulation was 1 mm at right angles and torsion of acupuncture was produced 2 times per second for 1 minute. The kidneys were extracted and weighed after two weeks, and renal function was confirmed through blood urea nitrogen(BUN). We measured reactive oxygen species of the serum and kidney, and compared expression levels of superoxide dismutase(SOD), catalase, glutathione peroxidase(Gpx), nuclear factor erythroid derived 2-related factor 2(Nrf-2), heme oxygenase-1(HO-1), nuclear factor-${\kappa}B$(NF-${\kappa}B)$, cyclooxygenase-2(COX-2), inducible nitric oxide synthase (iNOS), Bax and Cytochrome c. Results : The $LR_3$ acupuncture group and $BL_{23}$ acupuncture group experienced significantly increased kidney weight, and decreased BUN compared to control group. In terms of oxidative stress, the $LR_3$ acupuncture group and $BL_{23}$ acupuncture group experienced significantly reduced reactive oxygen species compared to the control group. Conclusions : The $LR_3$ acupuncture group and $BL_{23}$ acupuncture group experienced showed the effects of antioxidant, anti-inflammatory and apoptosis protection. The $BL_{23}$ acupuncture group was more effective than $LR_3$ acupuncture group.

• 대한불안의학회지
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• 제4권1호
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• pp.19-27
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• 2008

Objective : This study was conducted to evaluate the changes in the levels of neurotransmitters and cortisol in patients with chronic posttraumatic stress disorder (PTSD) and to evaluate their correlation with symptoms after long-term pharmacological treatment. Methods : Twenty-eight Vietnam veterans with chronic PTSD and 34 non-PTSD patients were consecutively recruited. The Combat Exposure Scale (CES), Mississippi Scale for Combat-Related Posttraumatic Stress Disorder (M-PTSD), Clinician Administered PTSD Scale (CAPS), Hamilton Rating Scale for Depression (HRSD) and Hamilton Anxiety Scale (HAS) were used to evaluate symptom severity. High performance liquid chromatography (HPLC) was used to measure the plasma levels of epinephrine, norepinephrine, and dopamine, and a radioimmunoassay (RIA) was performed to evaluate the plasma level of cortisol. Results : Plasma cortisol was significantly lower in PTSD patients than in control subjects, while there was no significant difference in plasma epinephrine, norepinephrine and dopamine between the two groups. The scores of M-PTSD, CAPS, HAMD and HAMA were signigicantly higher in PTSD patients than control group. Conclusion : After long-term treatment, the levels of neurotransmitters in PTSD patients returned to within the normal range, and the patients' symptoms showed some improvement. However, the core symptoms of PTSD continued to appear intermittently, and they are thought to be associated with hormonal systems, such as the HPA axis. It is also suggested that PTSD should be considered to be a complex disorder associated with multiple systems and that combinations of the effective medications for each system should be used to treat patients with PTSD.

• 대한한방내과학회지
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• 제21권1호
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• pp.74-86
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• 2000

Objectives : This is the experimental paper to study the curative and preventive effects of Dansambohyultang, Methods : Oriental herb medicine for gastro-intestinal disease caused by stress, on the rats put under the stress through starvation, heating and immoblization, the author used four different group; the normal group, which was not put under stress and well fed, and the control group, to which the drug was not administered and put under the stress through starvation, heating and immoblization, the Sample I, to which the drug was administered before they were put under stress, the Sample lI, to which the drug was administered after they were put under stress. Results : When a Masson's trichrome stain method was applied to the control group, a small size of ulcer was found in the fundus and the pylorus, and atrophy was observed in the neck region of mucous membrane. When the drug was administered to the Sample I and the Sample II, the former recovered from the ulcer and atrophy to almost normal and showed better results than the latter. When a Masson's trichrome stain method was applied to the control group, atrophy of mucous membrane was found all over the intestines. When the drug was administered to the Sample I and the Sample ll, the curative and recovered effects was seen in both, but the former showed better results than the latter. After application of Mayer's hematoxylin stain method, the observation of numerical changes of goblet cells in the small intestines showed the most significant decrease in the control group. In the Sample I, the number of the cells in the duodenum, the jejunum and the ileum returned to an almost normal level. In the Sample II, a slight increase was observed only in the ileum. After application of Mayer's hematoxylin stain method, the observation of numerical changes of goblet cell in the large intestines showed a significant decreased in the control group. Both the Sample I and the Sample II showed an increase in the number of goblet cells in comparison with the control group. When a serotonin-immunoreaction test was applied, the control group showed a general decrease in the number of gastro-entero-endocrine cells, The Sample I showed the effect in all over gastro.intestinal tract as compared with control group and the Sample II showed the effect in all over gastro-intestinal tract except the duodenum and the former showed better results than the latter. Conclusion : According to the above results, the regions which are most sensitive to stress were observed to the ileum and the colon. It was concluded that Dansambohyultang has a remedical value particularly on the abnormalities caused by stress in all over gastro-intestinal tract and it was found to be more effective in the Sample I than in the Sample ll. Judging from the fact that the Sample I showed better results than the Sample ll, Dansambohyultang can be said to have a preventive effect more than a curative effect on gastro-intestinal tract disease.

• 대한토목학회논문집
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• 제28권4A호
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• pp.537-548
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• 2008

최근 들어 비부착 강선을 이용한 프리스트레스트 콘크리트 구조물의 건설이 증가하고 있다. 그러나 극한거동 해석 시 단면 적합조건을 이용하는 내부 부착 강선과는 다르게 비부착 강선은 부재의 전체거동에 의해서 응력 증가량이 결정된다. 또한 외부 강선의 경우에는 편향부에서의 미끌림 효과와 강선의 편심 변화 효과 등이 발생하게 된다. 따라서 본 연구는 비부착 강선을 가지는 프리스트레스트 콘크리트(PSC) 보의 거동 특성을 평가하고 비부착 강선의 극한 응력을 구하기 위하여 지간길이/유효깊이, 콘크리트 압축강도, 철근비 및 기존 부착강선의 영향 등을 변수로 하여 정적 휨실험을 수행하여 비부착 강선 부재의 휨거동 특성을 얻었다. 실험결과에 의하면 균열하중, 철근 항복 하중 및 파괴하중의 경우, 콘크리트 강도보다는 철근비의 영향이 더 크게 나타났으며, 강도 측면에서는 고강도의 경우가 저강도의 경우보다 약간은 구조 성능이 우수하나, 큰 차이는 없는 것으로 나타났다. 또한 L/dp 값이 커질수록 훨씬 더 긴 구간의 연성 거동이 있는 것으로 나타났다. 이는 철근 항복 이후 비부착 강선의 기여가 상당히 크다는 것을 알 수 있었으며, ACI-318에서 제시하고 있는 비부착 강선의 극한 응력식은 실험 결과와 잘 일치하지 않으며, 경향성도 없는 것으로 나타났다. 실험결과 들을 분석하여 미끌림 현상이 없는 비부착 강선의 극한응력에 대한 예측식을 제안하였다. 제안된 예측식은 실험결과와 비교적 잘 일치하는 것으로 나타났으며, 미끌림 현상이 없는 비부착 강선의 극한 휨거동 평가, PSC 부재 해석 및 설계 시 본 연구에서 제안된 식은 유용한 기초가 될 것으로 사료된다.

• Journal of Ginseng Research
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• 제19권1호
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• pp.31-38
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• 1995

Antioxidant effect of Korean ginseng (Panax ginseng C.A. Meyer) was investigated in rats. Long-term administration of ginseng water extract protected the activity of liver cytosotic SOD, catalase and glutathione peroxidase from being significantly decreased with advancing age (p<0.05). It was more effective toward glutathione peroxidase than other antioxidant enzymes. However, the level of sulfhydryl compounds and its related enzymes such as glutathione reductase and glutathione-5-transferase was not significantly changed by the administration of ginseng. Liver microsomal formation of reactive oxygen species such as superoxide and hydrogen peroxide did not show a significant difference between two groups although it was slightly decreased with age, but lipid peroxidizability of microsomal membrane induced by a prooxidant was slightly lower in ginseng-treated rats. Interestingly, antioxidant capacity of plasma from ginseng treated rats on autooxidation of ok-brain homogenates was much higher than that of normal ones. However, resistance of RBC membrane against oxidative stress showed a similar tendency. The content of serum TBA reactive substances lowered consistently in the rats treated with r ginseng at all corresponding age and a significant difference between two groups was found at 24 months of age (p<0.05). Ginseng extract protected lipid peroxidation in brain and liver. This protection was more effective in the stressed rats imposed by immobilization than normal ones. In conclusion, ginseng water extract protected the age related deterioration of major antioxidant enzymes, and this effect was more striking with increasing duration of treatment. This comprehensive antioxidant action of ginseng seems to be bra certain action of ginseng other than a direct antioxidant action, which might be a long term normalizing effect through the harmony of various components.

• Journal of applied mathematics & informatics
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• 제26권1_2호
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• pp.355-364
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• 2008

Under pathological stress stimuli, dynamics of a biological system can be changed by alteration of several components such as functional proteins, ultimately leading to disease state. These dynamics in disease state can be modeled using differential equations in which kinetic or system parameters can be obtained from experimental data. One of the most effective ways to restore a particular disease state of biology system (i.e., cell, organ and organism) into the normal state makes optimization of the altered components usually represented by system parameters in the differential equations. There has been no such approach as far as we know. Here we show this approach with a cardiac hypertrophy model in which we obtain the existence of the optimal parameters and construct an optimal system which can be used to find the optimal parameters.

• Geomechanics and Engineering
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• 제10권1호
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• pp.1-19
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• 2016

This paper presents the results of an intensive experimental investigation on cyclic behavior of various sands and structural materials interface. Comprehensive measurements of the horizontal displacement and shear stresses developed during testing were performed using an automated constant normal load (CNL) cyclic direct shear test apparatus. Two different particle sizes (0.5 mm-0.25 mm and, 2.0 mm-1.0 mm) of sands having distinct shapes (rounded and angular) were tested in a cyclic direct shear testing apparatus at two vertical stress levels (${\sigma}=50kPa$, and 100 kPa) and two rates of displacement ($R_D=2.0mm/min$, and 0.025 mm/min) against various structural materials (i.e., steel, concrete, and wood). The cyclic direct shear tests performed during this investigation indicate that (i) the shear stresses developed during shearing highly depend on both the shape and size of sand grains; (ii) characteristics of the structural materials are closely related to interface response; and (iii) the rate of displacement is slightly effective on the results.