• 한국어류학회지
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• 제21권2호
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• pp.87-92
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• 2009

논에 서식하는 미꾸라지의 등, 체측, 후두부 피부조직에 대한 조직학적 연구를 통해 계절변화에 따른 점액세포의 변화여부를 조사하였다. 계절이 변화함에 따라 표피조직의 일반적인 형태에는 변화가 없었으나 상피조직에 존재하는 점액세포의 단위면적당 개수와 크기가 유동적으로 변화하였다. 비록 점액세포의 발달정도는 겨울철에 크게 증가하고 여름철에 감소하는 경향을 보였지만, 농지경작을 위해 관개를 실시한 봄(3~4월)과 추수를 위해 물을 배수시켜 미꾸라지의 피부가 공기에 노출되었던 가을(8~9월)에 점액세포의 월별 변화율이 가장 크게 조사되었다. 또한 농지 수온이 급격하게 높았던 6월에 점액세포가 일시적으로 발달하는 모습이 관찰되었다. 계절에 따른 점액세포의 변화는 유동적인 농지환경에 대한 능동적 행동이자 피부호흡을 하기 위함으로 여겨진다.

• 한국융합학회논문지
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• 제10권4호
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• pp.139-145
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• 2019

이 논문은 복합 입체형 트러스 단위구조체에 대한 강도 및 강성을 연구하였다. 사용된 모델은카고메 모델과 정육면체 트러스 모델을 합한 core-filled 모델이다. 해석을 위해 사용한 재질 특성은 304 스테인레스 스틸로 탄성계수는 193GPa, 항복응력 215MPa이다. 이론식은 깁슨-애쉬비의 상대탄성 관계식을 바탕으로 이론식을 유도하였고, 상용도구인 Deform 3D를 사용하여 해석을 실시하였다. 결론적으로 이 단위모델에 대한 상대탄성력은 상대밀도의 1.25배와 상수 계수값과 상관관계를 형성하고, 탄성은 기공과 반비례한다. 그리고, 상대압축강도는 상대밀도와 1.25배의 상관관계를 이룬다. 이에 대한 증명은 실제 실험을 해야 하겠으며, 유도한 이론 관계식은 굽힘과 좌굴등의 기계적 거동을 추가로 고려해야 한다. 앞으로 입체공간의 구조에 따른 탄성 및 응력에 대해 지속적인 연구가 진행될 것이다.

• Journal of Electrochemical Science and Technology
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• 제15권3호
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• pp.373-387
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• 2024

The layout of the cathode flow field largely determines the net output power of the proton exchange membrane fuel cell (PEMFC). To make the normal mass transfer effect best, the longitudinal channel was waved based on four serpentine flow channels, and the effects of sag depth and longitudinal channel width on the output efficiency of the cell were explored. The results show that the wave channel design systematically enhances the forced convection between adjacent channels, which can prevent a large zone of oxygen starvation zone at the outlet of the channel. The increase of the normal velocity in the gas transmission process will inevitably induce a significant enhancement of the mass transfer effect and obtain a higher current density in the reaction zone. For the longitudinal channel width, it is found that increasing its size in the effective range can greatly reduce the channel pressure drop without reducing the output power, thereby improving the overall efficiency. When the sag depth and longitudinal channel width gradient are 0.6 mm and 0.2 mm respectively, PEMFC can obtain the best comprehensive performance.

• 한국식품조리과학회지
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• 제18권2호
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• pp.185-192
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• 2002

In the fabrication of sponge cakes, wheat flour was substituted by Dioscorea Japonica flour at 3%, 6%, and 9% (C1, C2, and C3, respectively), and the sensory, physicochemical, texture properties, viable cell counts and chromaticity of the samples were investigated and compared with the control cake (C0). The addition of Dioscorea Japonica flour increased the density of the sponge cake, but decreased the size and moisture content of the cakes (C0〉C1〉C2〉C3). The pH value increased with increasing Dioscorea Japonica flour in the sponge cakes, and the microbial growth was remarkably suppressed by Dioscorea Japonica flour compared with the control. There was an increase in the chromaticity of the sponge cakes with increased Dioscorea Japonica flour in the cakes. Also, the hardness, gumminess, and chewiness were enhanced approximately two times higher than those of control by increasing Dioscorea Japonica flour. In the sensory evaluation, the addition of Dioscorea Japonica flour into sponge cakes showed a significant increment in the internal color, size/uniformity of the voids, and the sweetness, while the adhesiveness and moistness were the highest in the control. The overall preference was in the order C0〉C2〉C3〉Cl, and therefore, the substitution of 6% of wheat flour by Dioscorea Japonica was recommended in the fabrication of sponge cakes.

• 한국태양에너지학회 논문집
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• 제32권spc3호
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• pp.282-288
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• 2012

Proton exchange membrane fuel cell (PEMFC) is the most promising energy source for the robot applications because it has unique advantages such as high energy density, no power drop during operating, and easy to make compact size. However, PEMFC has intrinsic disadvantages which are delay to start up and difficulty to correspond drastic load changes. These disadvantages can be compensated by hybrid operating with a Li-poly battery. This study is focus to build and understand the hybrid system for the robot system. In this study, we build the PEMFC hybrid system using EOS-320 PEMFC stack, Li-poly battery and G-Philos FDX1-250BU dc-dc converter. The hybrid system is accurately monitored by CAN and RS485. The system was studied under two conditions such as non-loaded and loaded operating conditions. The results show that the system has delay to start up without hybrid operating and it can be compensated with the hybrid operating.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.119.1-119
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• 2003

The glyoxysomal nature of microbodies was determined in Botryosphaeria dothidea hyphae based on morphology and in situ enzyme characteristics by transmission electron microscopy and cytochemistry. Bound by a single membrane, microbodies had a homogeneous matrix and varied in size ranging from 200 to 400 m in diameter. Microbodies had crystalline inclusion(s) which consisted of parallel arrays of fine tubules in their matrices. Microbodies and lipid globules were frequently placed in close association with each other, forming microbody-lipid globule complexes in hyphae. The cytochemical activities of catalase and malate synthase were localized in matrices of microbodies, showing intense electron-density of the organelle. In addition, the immunogold labeling detected the presence of catalase in multivesicular bodies and hyphal cell walls as well as in matrices and crystalline inclusions of microbodies, supporting the enzyme secretion through cell walls. Meanwhile, isocitrate Iyase was localized only in matrices of microbodies. These results suggest that microbodies, particularly complexed with lipid globules, in the fungal hyphae are functionally defined as glyoxysomes, where glyoxysomal enzymes are biochemically active for the glyoxylate cycle to be a metabolic pathway in gluconeogenesis. (Mycology and Fugus Diseases)

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.229-233
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• 2012

Proton exchange membrane fuel cell (PEMFC) is the most promising energy source for the robot applications because it has unique advantages such as high energy density, no power drop during operating, and easy to make compact size. However, PEMFC has intrinsic disadvantages which are delay to start up and difficulty to correspond drastic load changes. These disadvantages can be compensated by hybrid operating with a Li-poly battery. This study is focus to build and understand the hybrid system for the robot system. In this study, we build the PEMFC hybrid system using EOS-320 PEMFC stack, Li-poly battery and G-Philos FDX1-250BU dc-dc converter. The hybrid system is accurately monitored by CAN and RS485. The system was studied under two conditions such as non-loaded and loaded operating conditions. The results show that the system has delay to start up without hybrid operating and it can be compensated with the hybrid operating.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 춘계학술발표대회 논문집
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• pp.74-77
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• 2001

The impact response and damage of CLAS panel was investigated experimentally. The facesheet material used was RO4003 woven-glass hydrocarbon/ceramic and the core material was Nomex honeycomb with a cell size of 3.2mm and a density of 96 kg/$\textrm{m}^{3}$. The shield plane used was RO4003 and 2024-T3 aluminum. Static indentation and impact test was conducted to characterize the type and extent of the damage observed in two CLAS panels, and the performance of antenna used in a wireless LAN system. Correlation of peak contact force, residual indentation and the delamination area shows impact damage of the panel with an aluminum shield plane is larger than that of the panel with RO4003 shield plane, although tile former is more penetration resistant. The damage was observed by naked eye, ultrasonic inspection and cross sectioning. The shape and size of delamination was estimated by ultrasonic inspection, and the area of delamination linearly increases as impact energy increases. The performance of impact damaged antenna was estimated by measuring return loss and radiation pattern.

• 대한수의학회지
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• 제32권1호
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• pp.77-82
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• 1992

세포 비병원성 소 설사병 바이러스가 감염된 우태아 폐세포를 이용 바이러스를 순수분리하여 이화학적 성상을 검사하였던 바 다음의 결과를 얻었다. 바이러스의 비중은 $1.090{\sim}1,114gm/cm^3$로 검출되었으며 $1,098gm/cm^3$에서 최대 감염가를 나타내었다. 면역 전자현미경을 이용한 형태학적 분석결과 30~80nm의 바이러스성 입자를 관찰할 수 있었으며 유전인자의 추출 분석결과 병원성 바이러스와의 전기영동상 유전자 규모에 있어서 차이는 인정되지 않았다. 그러나 비세포 병원성 소 설사병 바이러스는 병원성 바이러스에 비하여 세포외 배출이 적었으며 세포내에서 보다 많이 존재하는 것으로 관찰되었다.

• 한국미생물·생명공학회지
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• 제13권3호
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• pp.315-319
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• 1985

Barillus thuringiensis var. kurstaki와 Bacillus thuringiensis var. israelensis의 내독소 결정체와 아포를 NaBr 밀도 기울기 원심분리에 의하여 쉽게 분리하였으며, 전체 세포 무게에서 내독소 결정체의 무게의 비율은 BTK가 23.79%, BTI가 25%였다. BTK와 BTI의 내독소 결정체의 모형은 BTK는 이중 피라미드 형태이며, 성숙한 결정체의 길이는 1.7$\mu\textrm{m}$이었고, 중앙의 폭은 약 0.9$\mu\textrm{m}$였다. BTI의 내독소 결정체는 장타원형으로 큰 것은 길이가 1.6$\mu\textrm{m}$이고, 폭은 0.45$\mu\textrm{m}$였으며, 원형은 1.2$\times$0.8$\mu\textrm{m}$였다. 결정체 단백질의 분자량은 BTK의 것이 134,000달톤이었고, BTI의 결정체는 128,000 달톤이었다.