• 융합신호처리학회논문지
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• 제12권2호
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• pp.83-90
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• 2011

In cell biology area, microscopy enables detecting objects inside cells that are stained or fluorescently tagged. It is disadvantageous for observing these objects because of the noisy characteristics of their environmental surrounding. In this paper, a framework is proposed to increase the throughput and reliability for analysis of these images. First, we apply adaptive beamlet transform to extract edges meaningfully followed by orientation, location, and length in different scales. Then, a post-process is implemented to extend and map them onto original image. Our proposed scheme is compared with Canny edge detector and conventional beamlet transform from four evaluation aspects. It produces better results when experiments are conducted on real images. Much better results for observing internal parts make this framework competitive for analysis of cell images.

• 한국분말재료학회지
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• 제27권2호
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• pp.119-125
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• 2020

One of the promising candidates for accident-tolerant fuel (ATF), a ceramic microcell fuel, which can be distinguished by an unusual cell-like microstructure (UO₂ grain cell surrounded by a doped oxide cell wall), is being developed. This study deals with the microstructural observation of the constituent phases and the wetting behaviors of the cell wall materials in three kinds of ceramic microcell UO₂ pellets: Si-Ti-O (STO), Si-Cr-O (SCO), and Al-Si-Ti-O (ASTO). The chemical and physical states of the cell wall materials are estimated by HSC Chemistry and confirmed by experiment to be mixtures of Si-O and Ti-O for the STO; Si-O and Cr-O for SCO; and Si-O, Ti-O, and Al-Si-O for the ASTO. From their morphology at triple junctions, UO₂ grains appear to be wet by the Si-O or Al-Si-O rather than other oxides, providing a benefit on the capture-ability of the ceramic microcell cell wall. The wetting behavior can be explained by the relationships between the interface energy and the contact angle.

• 한국세라믹학회지
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• 제43권12호
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• pp.775-780
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• 2006

Mechanical and electrical performance of anode-supported SOFC single cells were analyzed after thermal cyclic operation. The experiments of thermal cyclic cell-operation were carried out four times and performance of each cell was measured at different temperatures of 650, 700, and $750^{\circ}C$, respectively. As increasing the number of thermal cycle test, single cells showed poor I-V characteristics and lower 4-point bending strength. The anode polarization was also measured by AC-impedance analysis. The observation of the microstructure of the anodes in single cells proved that the average particle size of Ni decreased and the porosity of anode increased. It is thought that the thermal cycle caused the degradation of performance of single cells by reducing the density of three-phase boundary region.

• 대기
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• 제17권4호
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• pp.435-453
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• 2007

KEOP (Korea Enhanced Observing Period)-2004 intensive summer observation was carried out from 20 June to 5 July 2004 over the Southwestern part of the Korean peninsula. In this study, the effects of KEOP-2004 intensive observation data on the simulation of precipitation system are investigated using KLAPS (Korea Local Analysis and Prediction System) and PSU/NCAR MM5. Three precipitation cases during the intensive observation are selected for detailed analysis. In addition to the control experiments using the traditional data for its initial and boundary conditions, two sensitivity experiments using KEOP data with and without Jindo radar are performed. Although it is hard to find a clear and consistent improvement in the verification score (threat score), it is found that the KEOP data play a role in improving the position and intensity of the simulated precipitation system. The experiments started at 00 and 12 UTC show more positive effect than those of 06 and 18 UTC. The effect of Jindo radar is dependent on the case. It plays a significant role in the heavy rain cases related to a mesoscale low over Changma front and the landing of a Typhoon. KEOP data produce more strong difference in the 06/18 UTC experiments than in 00/12 UTC, but give more positive effects in 00/12 UTC experiments. One of the possible explanations for this is that : KEOP data could properly correct the atmosphere around them when there are certain amounts of data, while gives excessive effect to the atmospheric field when there are few data. CRA analysis supports this reasoning. According to the CRA (Contiguous Rain Area) analysis, KEOP data in 00/12 UTC experiments improve only the surrounding area, resulting in essentially same precipitation system so the effects remain only in each convective cell rather than the system itself. On the other hand, KEOP data modify the precipitation system itself in 06/18 UTC experiments. Therefore the effects become amplified with time integration.

• 한국전기전자재료학회논문지
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• 제12권1호
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• pp.56-61
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• 1999

Highly conductive oxide films of BaRuO$_3$ have been grown heteroepitaxially on (100) LaAlO$_3$ single crystalline substrates by using pulsed laser deposition. The films are c-axis oriented with an in-plane epitaxial relationship of <010><100>BaRuO$_3$ // <110>LaAlO$_3$. Atomic force microscopy (AFM) observation shows that they consist of a fine-arranged network of grains and have a mosaic microstructure. Generally temperature-dependent resistivity shows the transition from metallic curve to semiconductor-metallic twofold curve by the deposition conditions for Ru oxide based materials like SrRuO$_3$, CaRuO$_3$, BaRuO$_3$, etc.. This twofold curve comes from the structural similarity of Ru oxide based materials including BaRuO$_3$. We find that the distance of Ru-Ru bonding in the unit cell of BaRuO$_3$ as well as the grain boundary scattering could be the two important causes of these interesting conductive properties.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권5호
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• pp.242-248
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• 2002

It is important to develop new effective technologies to increase the interruption capacity and to reduce the size of a UB(Gas Circuit Breakers). Major design parameters such as nozzle geometries and interrupting chamber dimensions affect the cooling of the arc and the breaking performance. But it is not easy to test real GCB model in practice as in theory. Therefore, a simulation tool based on a computational fluid dynamics(CFD) algorithm has been developed to facilitate an optimization of the interrupter. Special attention has been paid to the supersonic flow phenomena between contacts and the observation of hat-gas flow for estimating the breaking performance. However, there are many difficult problems in calculating the flow characteristics in a GCB such as shock wave and complex geometries, which may be either static or in relative motion. Although a number of mesh generation techniques are now available, the generation of meshes around complicated, multi-component geometries like a GCB is still a tedious and difficult task for the computational fluid dynamics. This paper presents the CFD program using CFB-CAD integration technique based on Cartesian cut-cell method, which could reduce researcher's efforts to generate the mesh and achieve the accurate representation of the geometry designed by a CAD tools.

• 한국가축번식학회지
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• 제10권1호
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• pp.100-108
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• 1986

Eik-Nes (1966) reported that the mechanism of spermatogenesis is controlled by FSH and LH and maintaned normally in scrotum terperautre which is 3-5$^{\circ}C$ lower than body termperature. But Ojeda and Ramirez (1972) have described that the abdominal testis was shrinked severely and lost its normal function in congenital cryptorchidism or surgically induced cryptorchidism. Ramirez and Sawyer (1974) reported that the compensatory hypertorphy occured in the remaining testis of unilateral castration and the scrotal testis of unilateral cryptorchidism. Cunninham et al. (1978) reported that the serum FSH levle increased after unilateral castration. Frankel and Wright (1982) reported that the serum LH level was unchanged greatly after unilateral castration. Gomes and Jain (1976) reported that the serum testosterone level increased temporarily but not varied after unilateral castration. On the other hand, Kormano et al. (1964) reported that the serum FSH level in unilateral cryptorchidism rat was unchanged in contrast with the control and Risbirdger et al. (1981) reported that the serum LH level was unchanged till 2 weeks after operation and after then increased to 77%. Kim (1984) reported that the serum testosterone level was somewhat lower than that fo control group but there was't significant different. There were many different reports on hormone levels among different investigators when the immarue rats were castrated unilaterally or induced cryptorchidism unilaterally. Liang and Liang (1970) and Cunningham et al. (1978) described that there were no true compenastory hypertrophy in the remaining testis of unilateral castration and scrotal testis of unilateral testis of unilateral cryptorchidism in rat but they grew faster than that of control. Kormano et al.(1964), Damber et al.(1976), Cunningham et al.(1978) and Karpe et al.(1981) reported that the testis weight, germinal epithelia height and seminiferous tubules diameter developed continuously and similarily in the control, the remaining testis of unilateral castration and scrotal testis of unilateral cryptorchidism increased, however, in the abdominal testis of the unilateral cryptorchidism, they were much smaller than those of other groups. In observation of the histological changes in the seminiferous epithelium of control, remaining tesis of unilateral castration and scrotal testis of unilateral cryptorchidism differentiated and developed fully(Cunningham et al., 1978). However, the abdominal testis of unilateral crytorchidism degenerated severely and only the germ cells in early stage and Sertoli cells were found in the seminiferous tubules. (Damber et al., 1976, Gomes and Jain, 1976 and Karpe et al., 1981). By electron microscopic observation, Nagano (1963) and Leason and Leeson (1970) found that the abdominal testis of unilateral cryptorchidism was thicked in boundary tissue, increased lipid droplet in the Sertoli cell, disarranged axial filament complex and increased lipid inclusions in the Sertoli cell.

• 한국양식학회지
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• 제11권4호
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• pp.475-485
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• 1998

동사리, Odontobutis platycephala 수컷의 명확한 생식주기를 밝히고자 1995년 12월부터 1997년 11월까지 생식소 중량지수(gonadosomatic index, GSI), 정소의 발달양상 및 혈중 성스테로이드 호르몬 변화양상을 조사하였다. 정소의 모양은 7월부터 10월까지는 콩깍지 모양이었는데, 11월부터는 후반부가 비대해져 올챙이와 유사한 형태였다. GSI는 7월부터 9월까지 0.14~0.18였으며, 10월에 $0.43{\pm}0.04$로 증가하여 2월까지 유의한 변화를 보이지 않았으나, 3월에는 $0.52{\pm}0.09$로 증가하였으며, 5월까지는 비슷한 수준에 머물렀다가, 6월에는 $0.28{\pm}0.05$로 낮아졌다. 생식주기에 따른 정소의 생식세포 발달은 전반부, 경계부, 후반부에서 다른 양상을 보였다. 7월의 대부분 개체의 정소는 세정관이 없었으며, 정자형성과정이 아직 시작되지 않은 상태로 정원세포들만을 볼 수 있었다. 전반부에서 정자형성단계의 세정관들은 8월에 출현하여 9월부터 12월까지는 80% 이상이었으며 1월부터 3월까지는 점차적으로, 4월에는 급격히 감소하여 6월에는 나타나지 않았다. 정자완성단계 세정관은 12월부터 출현하여 3월까지 점차적으로, 4월에 80%로 급격히 증가한 후 6월에 90%로 년 중 최고 수준에 이르렀다. 그러나 정자방출후 세정관은 나타나지 않았으며, 정원세포들은 7월에 100%, 8월에 65% 였으나 나머지 기간에는 20%이하로 년 중 존재하였다. 경계부에서도 8월부터 정자형성단계 세정관이 출현한 후 매월 증가하여 11월에 82%에 이르렀으며 12월부터 감소하여 3월부터는 나타나지 않았다. 정자완성단계 세정관은 11월에 출현하여 2월까지는 18% 이하였으나, 3월부터 6월까지 29%~57%의 수준을 보였다. 정자방출후 세정관은 3월부터 6월까지 12%~25%로 나타났다. 정원세포는 8월에 85%, 9월에 67%, 10월에 35%, 11월에 10%로 감소하였으며, 1월부터는 점차적으로 증가하여 4월에 50%를 보인후 6월까지 다시 점차적으로 감소하였다. 후반부에서는 일부의 개체에서 수개의 정원세포를 지닌 세정관이 7월부터 출현하였다. 정자형성단계에 세정관은 8월에 80%, 9월에 85%였으나 10월부터는 급격히 감소하여 11월에서 2월까지는 10%이하였으며, 3월부터는 나타나지 않았다. 정자완성단계 세정관은 8월에 출현하여 10월부터 급격히 증가해 11월에는 75%에 이르렀고 12월에는 15%로 급격히 감소하여 3월까지 유의한 변화를 보이지 않았으며 4월부터는 나타나지 않았다. 정자방출후 세정관은 11월에 출현하여 12월에 82%로 급격히 증가한 후 6월까지 85%~95%로 높은 수준을 유지하였다. 정원세포들은 8월에 15%로 감소하였으며 10월부터 3월까지는 나타나지 않았다. 그러나 4월부터 다시 출현하여 6월까지 10%이하에 머물렀다. 혈중 testosterone (T)의 농도는 8월부터 완만하게 증가하여 11월에 $0.61{\pm}0.09 ng/m\ell$ 였으며, 12월부터는 $3.99{\pm}1.22 ng/m\ell$로 급격히 상승하여 3월까지 높은 수준을 유지했다. 그러나 4월에 $0.52{\pm}0.14ng/m\ell$로 감소하기 시작하였으며, 5월에 $0.17{\pm}0.13 ng/m\ell$로 낮아진 후 7월까지 유의한 변화는 보이지 않았다(P<0.05). $17\alpha$,$20\beta$-dihyd-roxy-4-pregnen-3-one ($17\alpha$,$20\beta$-P)은 12월에 $0.19{\pm}0.01 ng/m\ell$로 약간 감소하였으며, 4월까지는 유의한 변화는 보이지 않고, 5월에 $0.38{\pm}0.03 ng/m\ell$로 급격히 증가하여 peak에 달하였다. 6월에는 $0.19{\pm}0.04 ng/m\ell$로 낮아졌으며, 11월까지 유의한 변화는 보이지 않았다(P<0.05). 이상의 결과를 종합하면 동사리는 정소의 부위에 따라 각각 다른 발달양상을 보였다. 즉 전반부에는 7월이 정원세포증식기, 8월~11월은 성숙초기, 12월~3월은 성숙중기, 4월~5월은 성숙후기, 6월은 기능적 성숙기로 구분되었다. 경계부에서는 7월이 정원세포 증식기, 8월~10월은 성숙초기, 11월~2월은 성숙중기였으며, 3월~6월은 성숙후기, 기능적 성숙기, 후번식기의 특징이 동시에 출현하였다. 후반부에서는 7월이 정원세포증식기, 8월~9월은 성숙중기, 10월은 성숙후기, 11월은 기능적 성숙기, 12월~6월은 후번식기로 구분되었다. 이러한 생식주기의 변화는 성스테로이드 호르몬의 변화양상과 밀접한 관련이 있는 것으로 생각된다.