• 한국식품과학회지
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• 제18권5호
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• pp.351-356
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• 1986

단(單)원통형 및 원통형 드럼건조기를 이용하여 잘게 저민 생선으로부터 플레이크를 성공적으로 만들 수 있었다. 생선의 높은 지방함량으로 인해 저민 생선이 드럼에 잘 들러붙지 않는 문제점은 타피오카가루의 형태로 2.5%의 전분을 저민 생선에 첨가함으로서 건조양상에는 영향을 미치지 않으면서 해결될 수 있었다. 제품의 수분함량을 일정한 수준으로 유지할 경우 건고형분(乾固形分)의 생산속도는 드럼간의 간격을 최소로 줄였을때 최고에 도달하였다. 건고형분(乾固形分)의 생산속도는 드럼의 회전속도가 증가할수록 선형적으로 증가하였고 제품의 품질이 손상되지 않는 범위에서 스팀의 압력이 높을수록 증가하였다. 총괄 열전달계수는 드럼의 회전수가 증가함에 따라 증가한 반면에 드럼간의 간격이 커짐에 따라 증가하지는 않았다. $MR\;=\;A\;\exp(\;-k{\theta})$로 표시되는 가장 보편적인 건조 모델식이 드럼건조에도 적용될 수 있었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.308-308
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• 2013

본 연구에 염료감응형 태양전지(Dye Sensitized Solar Cells; DSSCs)의 광전변환효율을 높이기 위해 작업전극에 새로운 구조의 광투과층 및 산란층을 도입하였다. DSSCs 작업전극의 빛을 투과시키는 투과층에 크기가 10 nm 이하의 nanoparticle $TiO_2$를 적용하고, 투과된 빛이 산란되어 많은 전자가 여기 될 수 있도록 기존의 큰 입자 사이즈였던 산란층을 이용하는 대신 $TiO_2$ nanorod 및 nanotube 형태의 구조를 도입하여 기존의 작업전극과 비교하였다. 산란층에서 방향성을 가지는 rutile 상의 $TiO_2$는 저온에서 안정적인 anatase 상의 $TiO_2$보다 화학적으로 안정하며, 높은 산란율을 가지고, 광에 의해 여기된 전자를 직접적으로 집전전극에 전달해 줌으로서 소자의 효율을 증가시킨다고 보고되고 있다. Rutile 상의 $TiO_2$ 층 제작 시 수열합성법을 이용하면 nanorod 모양의 $TiO_2$층을 형성할 수 있고, 이와 같은 방법으로 성장시킨 산란층에 전기영동법의 식각 효과를 사용하면 nanotube 모양의 $TiO_2$층을 성장시킬 수 있어 산란효과의 극대화 및 전극의 표면적을 넓히는 장점이 있다. 각각의 방법을 이용하여 만든 구조 위에 입자 크기 10 nm의 $TiO_2$를 Dr blade 방법으로 도포하여 double layer (산란층+흡수층)로 구성된 작업 전극을 이용한 DSSCs를 제작한 후 I-V curve와 EIS (Electrochemical Impedance Spectroscopy)를 측정하여 효율 및 전기화학적 특성을 분석하였다.

• 한국유체기계학회 논문집
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• 제7권1호
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• pp.17-23
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• 2004

Aeroacoustic characteristics of sirocco fan used in Over-The-Range (OTR) has been analyzed in this paper. A microwave hood combination over the gas range is short for the OTR. The flow phenomena of the double-sided sirocco fan was analyzed numerically and experimentally by using commercial code and three dimensional PIV for flow visualization. Also, microphone array is used in order to understand acoustic characteristics of OTR. Two dimensional unsteady flow and acoustic simulation is tried to qualitatively estimate the effects of tonal noise and broadband noise on the overall sound pressure level. It is found that tonal sound is generated from the strong interaction between the impeller and cutoff while broadband sound is generated from the strong secondary flows along the scroll surface. To reduce the noise level, the V-shape cut-off was applied to improve the sound quality by reducing tonal noise. So the peak noise at BPF (Blade Passing Frequency) was almost reduced. The shape of flow-guide to suppress the secondary flow over the scroll surface was carefully checked. It is found that this affects flow pattern at the fan exit and reduces the broad band noise. Through this numerical and experimental study, the sound pressure level was lowered by 4dBA compared to that of the previous fan at the operating point.

• 대한조선학회논문집
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• 제53권5호
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• pp.343-352
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• 2016

In this study, a pre-swirl duct for the 180,000 DWT bulk carrier has been designed from a propulsion standpoint using CFD. The stern duct - designed by NMRI - was selected as the initial duct. The objective function is to minimize the value of delivered power in model scale. Design variables of the duct include duct angle, diameter, chord length, and vertical and horizontal displacements from the center. Design variables of the stators are blade number, arrangement angle, chord length, and pitch angle. A parametric design was carried out with the objective function obtained using CFD. Reynolds averaged Navier-Stokes equations have been solved; and the Reynolds stress model applied for the turbulent closure. A double body model is used for the treatment of free-surface. MRF and sliding mesh models have been applied to simulate the actuating propeller. A self-propulsion point has been obtained from the results of towing and self-propelled computations, i.e., form factor obtained from towing computation and towing forces obtained from self-propelled computations of two propeller rotating speeds. The reduction rate of the delivered power of the improved stern duct is 2.9%, whereas that of the initial stern duct is 1.3%. The pre-swirl duct with one inner stator in upper starboard and three outer stators in portside has been designed. The delivered power due to the designed pre-swirl duct is reduced by 5.8%.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.145-146
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• 2007

Dye-Sensitized Solar Cell Solar cells(DSSC) were appeared for overcoming global environmental problems and lack of fossil fuel problems. And it is one of study field that is getting into the spotlight lately because manufacturing method is more simple and inexpensive than existing silicon solar cells. Oxide semiconductor is used for adsorption of dye and electron transfer in DSSC study, and $TiO_2$ is used most usually. Overall light conversion efficiency is changed by several elements such as $TiO_2$ particle size and structure, pore size and shape. In this study, we report the solar cell performance of titania$(TiO_2)$ film electrodes with various particle sizes. $TiO_2$ particle size was 16 nm, 25 nm, and mixture of 16nm and 25 nm, and manufactured using Doctor blade method. When applied each $TiO_2$ film to DSSC, the best efficiency was found at 16nm of $TiO_2$ particle. 16nm of $TiO_2$ particle has the highest efficiency compared to the others, because particles with smaller diameters would adsorb more dye due to larger surface area. And in case of the mixture of 16nm and 25 nm, the surface area was smaller than expected. It is estimated that double layer is adsorbed a large amount of chemisorbed dye and improved light scattering leading due to efficiency concentration light than mono layer.

• 대한수의학회지
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• 제58권4호
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• pp.171-175
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• 2018

The aim of this study was to investigate morphological development of filiform papillae (FP) in Korean native goats by using scanning electron microscopy. Tongues were removed from goat fetuses (days 60, 90, and 120), neonates, and juveniles (days 30, 60, 90, 120, 150, and 180 after birth). During the prenatal period, primordia of FP appeared at fetal day 60 and were observed to be developed at day 90. At fetal day 120, the FP were observed like flower leaves of a double flower bud. In neonates, FP were shaped like an obliquely sectioned cylinder with secondary papillae irregularly arranged in a saw blade-like manner. In 60-day-old juvenile goats, the FP were densely distributed at the inner base of 1/3-1/2 degrees. In 90-, 120-, and 150-day-old goats, FP were compacted at the inner base of 1/2-2/3, 3/4, and 4/5 degrees, respectively. In 180-day-old goats, FP were found to be completely compacted on the inner surface with complete morphogenesis. Microridges, microplicae, and micropits were well-developed on the epithelial surface of lingual papillae from embryonic day 120 to juvenile day 180. These results indicate that FP of goats have different shapes and sizes during development both before and after birth.

• 한국임상수의학회지
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• 제7권2호
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• pp.511-515
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• 1990

소에 있어서 효율적인 쌍자생산 방법을 검토하기 위하여 이분수정란의 이식, 저단위 FSH에 의한 다배란 유도후의 인공수정, 인공수정후의 수정란이식, 수정란 2개의 양측 및 단측 자각에의 이식 등의 방범을 적용하여 본 실험을 수행하였다. 각 실험군의 60일 수태율은 각각 34.8%, 65.0%(평균), 66.7%, 62.5%, 57.1%였으며 쌍태임신율은 8.7%, 15.0%(평균), 16.7%, 18.7%, 21.4%였다. 위의 결과에서 볼 때 저단위 FSH 투여법(Group B1)과 수정란 2개의 단측 자궁각 이식방법에 있어 쌍태율이 높게 나타나는 경향이 있었으나 실용적 측면에서는 낮은 수준이었다.

• 한국육종학회지
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• 제43권6호
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• pp.591-594
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• 2011

포인세티아(Euphorbia pulcherrima. Willd. ex Klotzch) 'Red Stone' 품종은 국립원예특작과학원에서 2009년도에 육성한 품종이다. 이 품종은 2006년에 생육이 왕성하고 진한 분홍색의 'Freedom Rose'를 모본으로, 착색이 빠르고 분홍색인 'Enduring Pink'를 부본으로 인공교배하여 양성된 실생계통 중에서 선발되었다. 2007~2008년 2차에 거쳐 특성검정을하여 '원교 D5-65'를 육성하였고 2009년에 3차 특성검정과 품평회를 실시하여 최종선발 하였으며, 농작물 직무육성 신품종선정위원회를 거쳐 '레드 스톤(Red Stone)'으로 명명하였다. 포엽의 형태는 도란형이며 포엽의 엽맥 사이에 강한 주름이 있고 포엽의 색상은 적색이다. 잎몸은 난형이며 진한 녹색이고 엽절의 수와 깊이는 중간이다. 줄기 색은 적색계이며 적심을 하지 않은 상태에서도 분지가 왕성하게 발생하고 줄기의 수는 많다. 초장은 작으며 단일처리 후 약 7.5주일이 경과하면 완전히 착색되어 출하가 가능하다.

• 한국농공학회지
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• 제17권3호
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• pp.3860-3871
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• 1975

This experiment was carried out to establish the mechanized methods in stumping and root-clearing, which were the most important works in the reclamation of sloping uplands. The determination of optimum teeth interval of rake blades and its operation methods to reduce the quantity of transported topsoil during the works, are the aims of this investigation. A newly designed rake blade, whose net teeth intervals could be regulated by three stages as 15cm, 25cm, and 35cm, was manufactured to attach to the bulldozer of 13ton. The experiments were carried out at Kilsang-Myon, Kwangwha-Gun, from Aug. 9 to Aug. 23, 1975. For each interval, 36 test plots of 50${\times}$10mn in size, which were regulated under three levels of land slopes of 10, 20, and 30% and two different tree stand density of high or medium values, were randomly chosen and arranged by two-replicated split-split plot design. Each stump classified by its diameter was stumped and cleared by the rake dozer to be related between diameter and stumping time. The results obtained in this experiment can be summarized as follows: 1. Stumping times for the diameters ranging from 6 to 18cm of stumps are almost the same and they are not varied by the difference of teeth intervals of rake dozer. 2. By back-ward stumping method, the number of stumps which can be stumped per hour ranges almost from 100 to 170, showing significant difference with respect to the teeth intervals. The working area is sharply varied with not only the stand density of stumps but the teeth intervals. 3. Optimum stumping distance for each teeth interval of rake dozer to minimize the quantity of transported topsoil are varied with such the rates as it is 15m or 20m for 15cm of teeth interval, but 25m for 25cm or 35cm, respectively. The clearing distance could be chosen almost double as long as the operating distance. 4. The working areas per hour of the simultaneous stumping and clearing methods are no significant difference among the various treatments of working conditions, but they are affected by the operating techniques. However, the influencing factors of the working conditions as classified before and the working directions are ranged from 10 to 15 per cent of total working area, respectively. 5. The residual rates of stumps which are not stumped by the rake dozer in each test plot are generally reduced as the teeth interval gets narrower, but there are no significant difference among them. The mean residual rates average to be about 4% for the simultaneous stumping and clearing method. The back-ward stumping method are recommended to be supervised and directed by more than one man, to show the operator where the stumps are located. 6. The results according to the stumping and clearing methods are summarized as Table IV-2. And the selection of working methods is recommended to follow as shown in Fig. IV-9 with respect to the stand density of the field. 7. Generally speaking, the narrower the teeth interval, the better become the working results, but the more the quantity of transported topsoil is increased. Therefore, it is recommended that the teeth interval should be reduced from the present distance of more than 30cm to 25cm or 15cm, by developing suitable working methods through more field works and experiments.