• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2004년도 학술대회지
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• pp.71-76
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• 2004

This paper investigate that the effect of the concrete containing mineral admixtures(pozzolanic materials such as fly-ash, ground granulated blast-furnace slag, silica fume and meta kaolin) on the resistance properties to chloride ion invasion. The purposed testing procedure was applied to the concrete added mineral admixtures for $3\sim4$ replacement ratios under W/B ratios ranged from 0.40 to 0.55. Specimens were immersed in $3.6\%$ NaCl solution for 330 days, and penetration depth, water soluble chloride contents and acid soluble chloride contents were measured in 28, 91, 182 and 330 days. Then, diffusion coefficient were calculated using total chloride contents. As a results. the kinds of mineral admixture and replacement ratios had a great effect on the resistance property of the concrete to chloride ion invasion compared with the plain concrete. And the optimal replacement ratios of mineral admixture had a limitation for each admixtures. The amount of acid soluble chloride ions and water soluble chloride ions were varied with the kinds of mineral admixtures and the penetration depth from the concrete skin. Chloride diffusion coefficient of each concretes decreased with the time elapsed. and the diffusion coefficients of the concrete immersed salt water for 330 days had a establishment with the compressive strength measured before immersing.

• Journal of the Korean Physical Society
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• 제73권9호
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• pp.1377-1384
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• 2018

Accurate measurement of the absorbed dose and the effective dose is required in dental panoramic radiography involving relatively low energy with a rotational X-ray tube system using long exposures. To determine the effectiveness of measuring the irradiation by using passive dosimetry, we compared the entrance skin doses by using a radiophotoluminescent glass dosimeter (RPL) and an optically stimulated luminescence detector (OSL) in a phantom model consisting of nine and 31 transverse sections. The parameters of the panoramic device were set to 80 kV, 4 mA, and 12 s in the standard program mode. The X-ray spectrum was applied in the same manner as the panoramic dose by using the SpekCalc Software. The results indicated a mass attenuation coefficient of $0.008226cm^2/g$, and an effective energy of 34 keV. The equivalent dose between the RPL and the OSL was calculated based on a product of the absorbed doses. The density of the aluminum attenuators was $2.699g/cm^3$. During the panoramic examination, tissue absorption doses with regard to the RPL were a surface dose of $75.33{\mu}Gy$ and a depth dose of $71.77{\mu}Gy$, those with regard to the OSL were surface dose of $9.2{\mu}Gy$ a depth dose of $70.39{\mu}Gy$ and a mean dose of $74.79{\mu}Gy$. The effective dose based on the International Commission on Radiological Protection Publication 103 tissue weighting factor for the RPL were $0.742{\mu}Sv$, $8.9{\mu}Sv$, $2.96{\mu}Sv$ and those for the OSL were $0.754{\mu}Sv$, $9.05{\mu}Sv$, and $3.018{\mu}Sv$ in the parotid and sublingual glands, orbit, and thyroid gland, respectively. The RPL was more effective than the OSL for measuring the absorbed radiation dose in low-energy systems with a rotational X-ray tube.

• Steel and Composite Structures
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• 제42권4호
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• pp.427-446
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• 2022

Cutouts in the beams or plates are often unavoidable due to inspection, maintenance, ventilation, structural aesthetics purpose, and sometimes to lighten the structures. Therefore, there will be a substantial reduction in the strength of the structure due to the introduction of the cutouts. However, these cutouts can be reinforced with the different patterns of ribs (stiffener) to enhance the strength of the structure. The present study highlights the influence of the elliptical cutout reinforced with a different pattern of ribs on the stability performance of such stiffened composite panels subjected to non-uniform edge loads by employing the Finite element (FE) technique. In the present formulation, a 9-noded heterosis element is used to model the skin, and a 3-noded isoparametric beam element is used to simulate the rib that is attached around a cutout in different patterns. The displacement compatibility condition is employed between the plate and stiffener, and arbitrary orientations are taken care by introducing respective transformation matrices. The effect of shear deformation and rotary inertia are incorporated in the formulation. A new mesh configuration is developed to house the attached ribs around an elliptical cutout with different patterns. Initially, a study is performed on the panels with different stiffener schemes for various ply orientations and for different stiffener depth to width ratios (d_s/b_s) to determine an optimal stiffener configuration. Further, various parametric studies are conducted on an obtained optimal stiffened panel to understand the effect of cutout size, cutout orientation, panel aspect ratio, and boundary conditions. Finally, from the analysis, it can be observed that the arrangement of the stiffener attached to a panel has a major impact on the buckling capacity of the stiffened panel. The stiffener's depth to width ratio also significantly influences the buckling characteristic.

• 대한의용생체공학회:의공학회지
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• 제19권6호
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• pp.617-622
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• 1998

신냉매인 R-404A를 사용하여 저온특성이 우수한 한냉물리치료기를 개발하였다. 임상평가를 통해서 침온도계를 슬관절 강 내 및 둔부근육 내에 삽입하여 직접 근육온도를 측정하였고, 적외선체열촬영기를 이용하여 표피온도를 객관적으로 측정하였다. 슬관절 부위에 대한 5분 동안의 한냉물리치료에 따른 표피 및 관절강 내 온도변화를 측정한 결과, 표피는 23.3${\pm}4.7^{circ}C$, 관절강 내는 4.1${\pm}1.0^{circ}C$의 온도저하를 보였으며 2~3시간이 경과한 후에도 한냉치료효과가 지속됨을 알 수 있었다. 냉기치료 후 둔부근육에서 측정된 최저온도는 2, 4, 6cm 깊이에서 각각 35.1${\pm}$0.7, 36.2${\pm}$0.4, 36.9${\pm}0.3^{circ}C$였고, 이에 도달하기까지의 시간은 각각 20${\pm}$3.0, 25${\pm}$4.5, 45${\pm}$8.5분이었다. 치료 후 2시간이 경과한 뒤의 온도는 근육의 2, 4, 6cm 깊이에서 각각 36.2${\pm}$0.5, 36.6${\pm}$0.3, 36.9${\pm}0.3^{circ}C$였고, 치료 전에 비해 유의한 온도 차이가 있었다. 또한 5분간 한냉을 가하는 동안 피부 및 근육 내에서 온도의 증가, 즉 반응성 혈관확장은 관찰되지 않았다. 본 연구를 통해서 개발된 한냉물리치료기는 근육의 연축 혹은 강직, 물리적 외상, 화상, 동통의 감소, 관절염 등에 효과적으로 사용되리라 생각된다.

• 한국자원식물학회지
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• 제16권3호
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• pp.264-274
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• 2003

한국감자육종소재 은행(KPGR)에서 는 많은 감자유전자원을 수집함과 동시에 수집된 유전자원을 분석해서 감자육종에 활용하고 있다 다양한 유전자원 중에서 2001년 우리나라 준고냉지 지역인 장평과 양구에서 수확한 58가지 감자 계통 및 품종에서 식용 및 칩 가공에 적합한 품종 및 계통을 선발하였다. 감자의 선발 기준은 지역적 응성, 감자 괴경형태(눈 깊이, 모양, 표피색, 육색, 생산량, 더뎅이병 저항성과 중심공동 및 내부갈색저항성)와 감자의 칩 색도에 아주 큰 영향을 주는 환원당 함량 등 요소를 종합적으로 고려하였다. 기존 '수미'와 대등한 흰색 표피 품종은 '얼리밸리', '썸머밸리', '윈터밸리', '태복밸리'였고, '골든밸리'는 노란색 품종으로, '고구밸리'와 '주스밸리'는 적색표피 품종으로, '퍼플밸리'는 보라색 표피 품종으로 각각 선발되었다. 가공용 재배 품종인 '대서' 칩 색도와 비슷하고 생산량(4.0톤ha)이 비교적 높고 환원당 함량(0.30％이하)이 비교적 낮은 24계통 및 품종이 선발되었다. 선발된 계통 및 품종의 괴경형태 등을 종합적으로 고려하여 '태동밸리', '강심밸리', '강원밸리' 품종이 밝은 흰 색칩용으로 선발되었는데 환원당 함량은 각각 0.23％, 0.27％와 0.29％였으며; '보라밸리', '로즈밸리', Valley54는 칼라 칩용으로 선발하였는데 그중 '보라밸리' 의 환원당 함량은 0.26％로서 밝은 보라색 칩색도를 나타냈으며 '로즈밸리'의 환원당 함량은 0.19％로서 칩 색도는 밝은 황색을 나타냈으며 밸리54의 환원당 함량은 0.27％였다. '스틱밸리'와 밸리72은 프렌치 프라이용으로 선발하였는데 환원당 함량은 각각 0.22％와 0.15％로서 괴경의 형태가 비교적 긴 형태로서 프라이 색도는 밝은 담황색을 나타냈다.

• 대한기계학회논문집B
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• 제39권11호
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• pp.897-903
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• 2015

본 연구에서는 냉온 자극요법의 열전달 특성을 정량적으로 파악하고자 한다. 축대칭 비압축성 Navier-Stokes 방정식 및 에너지 방정식의 해법을 위해 SIMPLE 알고리즘에 기반을 둔 유한체적법을 사용하였다. 혈액의 관류를 고려하기 위해 Pennes bio-heat 방정식을 추가로 적용하였다. 다양한 온도조건에 따른 피부 아래 각 지점에서의 열 침투양상을 분석하였다. 수치해석을 통하여 다양한 입력온도들에 대하여 역치 온도에 도달하는 영역들을 발견하였다. 또한, 페니스 효과로 인하여 피부 심부로 갈수록 외부 자극에 대한 온도변화가 완만함을 확인하였으며, 진피부분의 온도가 역치에 도달하기 위해서는 온 자극 및 냉 자극은 47도 및 7도 내외로 주어져야 함을 발견하였다. 본 논문의 수치해석을 통해 구축된 데이터베이스는 경혈 냉온 자극 치료기의 최적설계 시에 활용된다.

• 대한의료기공학회지
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• 제11권1호
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• pp.80-116
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• 2009

It studies into viewpoints of 7 doctors of Wenbing studies on macula. The results concerning characteristics, remedy and prevention of macula are as follows; Macule does not protrude on the surface of skin and does not have any color change for external stimulus, but rash out on the surface and becomes white when pushed. It becomes macule when the blood leaks beneath skin as stomach-heat of yangming enters into blood system and damages it. On the other hand, when heat enters lung meridian, penetrates beneath the skin and congeals inside the vessel, it becomes rash. When you combine symptoms of body and pulse with numbers, color, shape and distribution status of macula, you can diagnose the depth of rash, seriousness, the possibility of treatment and prognosis of macula. The remedy for macule consists of cooling heat of yaming, removing heat from the blood and relieving feverish rash, and the one for rash consists of facilitating meridian with aroma, expelling pathogenic factors from muscles with drugs of pungent flavor and cool nature and clearing away heat from the blood systems. It relieves the inhibited functional activities of lung-Ki, and helps extermination of rash as well as clearing heat of the vessel. Also, it is the most important to preserve resin of stomach for every treatment. It is good to avoid expelling pathogenic factors with drugs of pungent flavor and warm nature, raising drugs and invigorating drugs during treating macula. Moreover, the patients should not over dose cold-natured drugs and purgative therapy. There are common clinical symptoms of macula in advance, so right recognition of symptoms can contribute to prevention of macula.

• Journal of the Korean Wood Science and Technology
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• 제43권6호
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• pp.810-817
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• 2015

본 연구는 백합나무 스킨팀버의 ACQ-2, CUAZ-3, CuHDO-1 가압처리 특성을 평가하기 위해 수행되었다. 일차적으로 백합나무 변재부와 심재부 시험편을 대상으로 처리용 목재 함수율이 방부제 처리도에 미치는 영향을 평가하고, 방부제 유효성분인 구리의 처리목재 내 정착 특성을 조사하였다. 본 연구 결과에 의하면 백합나무 변재부는 방부제 종류에 관계없이 조사된 목재함수율 범위(50% 이하)에서 사용환경 범주 H3용 처리목재의 침윤도와 흡수량 기준을 모두 만족하였다. 백합나무 변재부의 방부제 보유량 경사를 조사한 결과, 국립산림과학원 고시 제2011-04호에 제시된 처리용 목재의 함수율(평균 30% 이하)을 만족할 경우 재면으로부터 15 mm 깊이까지에서 사용환경 범주 H3용 처리재의 흡수량 기준을 충족하였다. 백합나무 심재부는 처리도가 매우 불량하여 처리용 목재의 함수율 조건 및 방부제 종류에 관계없이 사용환경 범주 H3용 처리목재의 침윤도와 보유량 기준을 모두 만족시키지 못하였다. 백합나무 변재 및 심재 시험편 공히 비건조 양생보다 건조 양생에서 구리의 정착속도가 빠르고 또한 최종 구리 정착율이 높았으며, 3주간 비건조 양생 후 구리 정착율이 90% 수준에 머물었으며 양생기간을 연장하더라도 정착율은 크게 개선되지 않았다.

• 대한인간공학회지
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• 제33권4호
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• pp.299-311
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• 2014

Objective: The aim of this study was to develop a method for measuring breast size from three-dimensional (3D) body scan image data. Background: Previous bra studies established reference points by directly contacting the subject's naked skin to determine the boundary of the breast. But some subjects were uncomfortable with these types of measurements. This study examined noncontact methods of extracting breast reference points from 3D body scan data that were collected while subjects were wearing standardized soft bras. Method: 3D body scan data of 32 Korean women were analyzed. The subjects were selected from the Size Korea 2010 study. The breast landmarks were identified by graphic analyses of slicing contour lines on 3D body scan data. Results: Three methods determining bra cup size were compared. The M1 and M2 methods determined cup size by calculating the difference between bust girth and under-bust girth. The M3 method determined bra cup size by measuring breast arc length. Conclusion: The researchers proposed an anthropometric bra cup sizing system with the breast arc length (M3 method). It was measured from the geometrically defined landmarks on the 3D body scan slicing contour lines. The new bra cup size was highly correlated with breast depth. Application: The noncontact measuring method used in this study can be applied to the ergonomic studies measuring sensitive body parts.

• 한국자기공명학회논문지
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• 제22권2호
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• pp.26-33
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• 2018

Xanthium sibiricum is used as a traditional folk medicine for the treatment of cancer, fever, headache, nasal sinusitis, and skin pruritus. This study aimed to identify components from Xanthium sibiricum extracts using an SPE-800MHz NMR-MS hyphenated system. The simultaneous acquisition of MS and NMR spectra from the same chromatographic peaks significantly increases the depth of information acquired for the compound and allows the elucidation of structures that would not be possible using MS or NMR data alone. LC -NMR analysis was conducted using a HPLC separation system coupled to 800 MHz spectrometer equipped with a cryoprobe, and a SPE unit was used to automatically trap chromatographic peaks using a HPLC pump. LC-MS analysis was conducted with a Q-TOF MS instrument using ESI ionization in the negative ion mode. Using the hyphenated analysis, several secondary metabolites were identified, such as 3',5'-O-dicaffeoylquinic acid, 1',5'-O-dicaffeoyl- quinic acid, and ethyl caffeate. These results demonstrate that the SPE-800MHz NMR-MS hyphenated system can be used to identify metabolites within natural products that have complex mixtures.