• Carbon letters
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• 제3권3호
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• pp.127-132
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• 2002

Unidirectional polymer composites were prepared using high-strength carbon fibers as reinforcement and phenolic resin as matrix precursor with keeping fiber volume fraction at 30, 40, 50 and 60% respectively. These composites were carbonized at $1000^{\circ}C$ and graphitised at $2600^{\circ}C$ in the inert atmosphere. The carbonized and graphitised composites were characterized for mechanical properties as well as microstructure. Microscopic studies were carried out of the polished surface of carbonized and graphitised composites after etching by chromic acid, to understand the effect of fiber volume fraction on oxidation at fiber-matrix interface. It is found that the flexural strength in polymer composites increases with fiber volume fraction and so does for the carbonised composites. However, the trend was found to be reversed in graphitised composites. In all the carbonized composites anisotropic region has been observed at fiber-matrix interface which transforms into columnar type microstructure upon graphitisation. The extension of strong and weak columnar type microstructure is function of fiber volume fraction. SEM microscopy of the etched surface of the sample reveal that composites containing 40% fiber volume has minimum oxidation at the interface, revealing a strong interfacial bonding.

• 한국식품조리과학회지
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• 제16권4호
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• pp.352-357
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• 2000

This study was conducted to investigate the effect of the lipid and collagen content and drip volume on the hardness of fish meat. Red sea bream (cultured and wild) and flounder (cultured, cultured with obosan and wild) were used for this study. Textural differences between cultured and wild meats were determined by the measurements of hardness, lipid and collagen content, and drip volume. Lipid content of the dorsal muscle was higher especially in cultured red sea bream (3.32%) than in wild one. Cultured and wild flounder contained lower content of lipid than red sea bream. The content of collagen was higher in cultured flounder fed with obosan (8.37 mg/g muscle) and wild flounder (8.02 mg/g muscle) than others. Drip volume was the highest in cultured flounder fed with obosan (8.67%). The hardness of raw meat was correlated with the contents of lipid (r= -0.7063) and collagen (r= 0.8307), significantly. Cultured fish contained more lipid and less collagen than wild one. So, the hardness of these fish meats was lower than wild one. However, cultured flounder fed with obosan showed no difference in hardness compared with wild one. In the cooked meat, there was no relationship between the hardness of fish meat and the contents of lipid and collagen. But, the drip volume was significantly related with the hardness (r= 0.6870). From these results, the factors contributing the textural difference between wild and cultured fish meat would be the lipid and collagen contents, and two ways to improve the texture of cultured fish meat could be suggested. One is to lower the lipid content by feed control, and the other is to raise the collagen content by inducing more fish movement.

• 한국조리학회지
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• 제8권1호
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• pp.43-54
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• 2002

식빵의 기능성 강화를 위하여 밀가루에 chitosan을 1, 3, 5% 첨가하여 반죽의 발효력, 빵의 부피 및 비용적, 관능검사에 의한 품질평가, 노화진행 등의 분석으로 제빵에 미치는 영향을 조사한 결과는 다음과 같다. 1. 반죽의 발효력은 chitosan 1%, 첨가시 가장 양호하였으며 chitosan 양이 증가할수록 발효는 지연되었다. 2. 빵의 부피는 chitosan 1% 첨가시 가장 양호하였으며 chitosan 양이 증가할수록 부피가 작았고, 비용적도 chitosan 1% 첨가시에 가장 높은 값을 타나냈다. 3. 노화 진행 정도는 chitosan 1% 첨가시 가장 느리게 진행되었다. 4. 관능검사에 의한 빵의 품질 평가는 chitosan 1% 첨가시 가장 높은 값을 나타냈다. 따라서 본 연구로 chitosan을 1%, 첨가시 제빵 적성이 양호하였을 뿐만 아니라 chitosan을 함유한 기능성 식빵 개발이 가능한 것을 보여주었다.

• 사상체질의학회지
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• 제15권3호
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• pp.187-196
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• 2003

The aim of this thesis is to examine the effect of the diuretics in the Sasang constitutional medicine those are not categorized to the diuretic in the established herbal medicine by the way of measuring the change of body edema and the quantity of body moisture through the inbody test, along with the urine volume taken for 24 hours 1. We medicated the diuretic suggested by the DongyiSuseBowon東醫壽世保元 into the tested group and measured the change of the urine volume, the quantity of body moisture and the degree of body edema. The results are the followings below. 1) Soeumin The change in the urine volume and body moisture showed no responsibility, but the degree of body edema decreased with the responsibility. 2) Soyangin All of the degree of body edema and the urine volume, and body moisture showed decrease. 3) Taeumin The urine volume and body moisture increased but showed no responsibility. Also the degree of body edema decreased within the normal limit which can not be accepted. 4) The medicine of the Sasang Constitutional Medicine can not be simply thought to be the diuretic, but it has the function that excretes the moisture which functions negatively in the body and causes edema, as well as the function of the adjustment of metabolism that preserves the normal amount of moisture. This is the good example which is the concept of the adjustment therapy suggested by The Sasang Constitutional Medicine 2. Through the results above, we can find that the diuretic suggested by The Sasang Constitutional Medicine functions in the way that is differently explained by the herbal medicine.

• Archives of Plastic Surgery
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• 제35권1호
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• pp.62-66
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• 2008

Purpose: Axillary osmidrosis is a distressing disorder characterized by unpleasant odor from axillary area and it is mainly associated with apocrine glands but also associated with eccrine glands. For surgical treatment of osmidrosis, recently ultrasound assisted liposuction(UAL) had been performed for many patients. According to the recent studies about ultrasound assisted liposuction for the treatment of osmidrosis, histologic studies about apocrine gland had been applied for 35 cases, but there were rare mention about eccrine gland and the relationship between two glands. The purpose of this article is to evaluate the effect of ultrasound assisted liposuction for the treatment of axillary osmidrosis on apocrine and eccrine glands. Methods: From January 2004 to January 2007, 35 patients underwent ultrasound assisted liposuction for the treatment of osmidrosis and 5 patients underwent histologic studies. Histologic examinations were performed before and after ultrasound assisted liposuction and each biopsy was performed in central axillary area. The volume ratio of both glands, presence of degeneration were examined. And in aspirates, distribution and density of both glands and their morphological changes were examined. Results: Preoperative biopsy results showed average volume ratio of apocrine glands to eccrine glands was 65 : 35. According to the postoperative biopsy results, the volume of apocrine glands in dermis were significantly reduced and glands were degenerated, but the volume of eccrine glands were slightly reduced and glands were mildly damaged. And the average volume ratio of two glands was 20 : 80. According to biopsy results of aspirates, the volume ratio of two glands was 85 : 15 and apocrine glands had significantly greater proportion. Conclusion: By comparison of each biopsy result, apocrine glands were more significantly reduced and degenerated than eccrine glands in all 5 cases. However, further studies with large sample sizes and close examinations are required.

• 한국항만경제학회지
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• 제32권3호
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• pp.83-94
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• 2016

본 연구에서는 한국과 총 5개 단일국가(칠레, 싱가포르, 인도, 페루, 미국) 간 FTA 발효가 부산항 벌크물동량에 미치는 영향에 대한 실증분석을 시도하였다. 분석을 위해 대한민국과 FTA가 발효된 5개 국가(효과집단)와 2015년 기준 부산항 벌크물동량 교역 상위 80%의 비중을 차지하는 10개 국가(통제집단)의 횡단면 및 시계열로 구성된 패널자료를 사용하였다. 분석 결과 FTA 발효는 부산항 벌크물동량의 증대에 기여한 것으로 나타났다. FTA 이외의 GDP, 인구 변수는 부산항 벌크물동량과 양(+)의 효과를 보이는 것으로 나타났으며, 거리 변수는 물동량과 음(-)의 효과를 보이는 것으로 분석되었다. 국가별 패널자료는 하우스만 검정 및 LR검정을 통해 확률효과모형이 적합한 것으로 나타났다.

• 대한의용생체공학회:의공학회지
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• 제39권6호
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• pp.237-242
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• 2018

$^{18}F$-fludeoxyglucose PET (FDG-PET) can help finding an abnormal metabolic activity in brain. In this study, we evaluated an efficiency of volume- and cortical surface-based analysis which were used to determine whether standardized uptake value ratio (SUVR) of FDG-PET was different among Alzheimer's disease (AD), mild cognitive impairment (MCI), and healthy control (HC). Each PET image was rigidly co-registered to the corresponding magnetic resonance imaging (MRI) using mutual information. All voxels of the co-registered PET images were divided by the mean FDG uptake of the cerebellum cortex which was thresholded by partial volume effect (>0.9). Also, the SUVR value of each vertex was linearly interpolated from volumetric SUVR image which was thresholded by gray matter partial volume effect (>0.1). Lobar mean values were calculated from both volume- and cortical surface-based SUVRs. Statistical analysis was conducted to compare two measures for AD, MCI and HC groups. Even though the results of volume (SUVR_vol) and cortical surface-based SUVR (SUVR_surf) analysis were not significantly different from each other, the latter would be better for detecting group differences in SUVR of PET.

• Composites Research
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• 제34권2호
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• pp.129-135
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• 2021

본 논문에서는 필라멘트 와인딩 공정에서 발생하는 두께 방향 섬유체적비 불균일이 원통형 복합재 격자 구조의 좌굴하중에 미치는 영향을 확인하기 위해서 Vasiliev가 제안한 원통형 복합재 격자 구조 좌굴하중 이론식을 변형하여 섬유체적비에 따른 좌굴하중 저하를 확인하였다. 섬유체적비에 따라 격자 구조 리브의 각 층의 두께를 달리하였으며, 혼합법칙을 사용하여 각 층별로 물성치를 다르게 적용하였다. 구조물 크기, 두께, 섬유체적비 평균값을 달리한 유한요소모델에 대한 선형좌굴해석을 수행하였다. 최종적으로 이론식을 사용한 등가모델의 좌굴 하중 계산 결과와 유한요소해석 결과를 비교하여 두께 방향 섬유체적비 불균일이 원통형 복합재 격자 구조의 좌굴하중 저하의 원인이 될 수 있음을 확인하였다.

• 대기
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• 제31권2호
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• pp.157-170
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• 2021

To investigate the effect of snowfall on the traffic of general roads in Gangwon-do, case analysis was performed in Gangneung, Pyeongchang, and Chuncheon using ASOS (Automated Synoptic Observing System) snowfall data and VDS (Vehicle Detector System) traffic data. First, we analyzed how much the traffic volume and speed decrease in snowfall cases on regional roads compared to non-snow cases, and the characteristics of monthly reduction due to snowfall were investigated. In addition, Pearson correlation analysis and regression analysis were performed to quantitatively grasp the effect of snowfall on traffic volume and speed, and sensitivity tests for snowfall intensity and cumulative snowfall were performed. The results showed that the amount of snowfall caused decrease both in the traffic volume and speed from usual (non-snowfall) condition. However, the trend was different by region: The decrease rate in traffic volume was in the order of Gangneung (17~22%), Chuncheon (14~17%), and Pyeongchang (11~14%). The decrease rate in traffic speed was in the order of Chuncheon (9~10%), Gangneung (8~9%), Pyeongchang (5~6%). No significant results were found in the monthly decrease rate analysis. In all regions, traffic volume and speed showed a negative correlation with snowfall. It was confirmed that the greater the amount of traffic entering the road, the greater the slope of the trend line indicating the change in snowfall due to the traffic volume. As a result of the sensitivity test for snowfall intensity and cumulative snowfall, the snowfall information at intervals of 6-hours was the most significant.

• 대한기계학회논문집A
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• 제25권1호
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• pp.25-31
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• 2001

The theoretical modeling to predict the modulus of elasticity by the shape memory effect of dispersed particles in a metal matrix composite was studied. The modeling approach is based on the Eshelbys equivalent inclusion method and Mori-Tanakas mean field theory. The calculation was performed on the TiNi particle dispersed Al metal matrix composites(PDMMC) with varying volume fractions and prestrains of the particle. It was found that the prestrain has no effect on the Yonugs modulus of PDMMC but the volume fraction does affects it. This approach has an advantage of definite control of Youngs modulus in PDMMCs.