• Applied Chemistry for Engineering
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• v.7 no.3
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• pp.464-472
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• 1996

The mechanism of thin-film formation by Ionized Cluster Beam Deposition(ICBD) was investigated. A simulation program based on the Monte-Carlo method was developed in order to investigate the effects of the acceleration voltage, substrate temperature, activation energy for the surface migration, and critical nuclei size on grain size and surface roughness. Studies of the effect of kinetic energy of clusters on the film formation processes revealed that high acceleration voltage enhanced the surface-migration of adatoms and made it easier for an epitaxial film to be formed. The relaxation time of kinetic energy of adatoms increased with the substrate temperature, which in turn increased the grain size of the crystalline film. This effect was more clearly distinguished when the critical nuclei size was large. The surface-migration activation energy was found to affect the interaction between the adatoms and the substrate and thus the relaxation time of kinetic energy. Investigations of the surface roughness revealed that the acceleration voltage, the substrate temperature, and the surface-migration activation energy exerted a collective effect on the morphology of the film surface.

• Korean Journal of Plant Taxonomy
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• v.47 no.4
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• pp.297-303
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• 2017

In central and southern Korea, the two small insectivorous, terrestrial herbs, Utricularia bifida and U. caerulea, often co-occur at wet locations (or in wetlands). The Korean Peninsula (with central China and northern Japan) constitutes the northern edge of their distribution, as their main range is subtropical and tropical Asia. The Korean populations of both species are very likely of post-glacial origin, given that warm-temperate vegetation was absent from the Korean Peninsula during the Last Glacial Maximum. Two hypotheses of the post-glacial colonization of the peninsula can be formulated; first, if current populations were founded by propagules coming from a single ancestral population (i.e., a single refugium), we would expect low levels of genetic diversity. Alternatively, if contemporary Korean populations originated from multiple sources (multiple refugia), we would expect high levels of genetic variation. To test which is more likely, we surveyed the degree of allozyme variation at 20 loci in ten populations for each of the two species from southern Korea. We found no allozyme variation within each species. However, their aquatic congener U. australis exhibited allozyme polymorphism across Japan (four polymorphic loci at three enzyme systems). We suggest that southern Korean populations of Utricularia bifida and U. caerulea were established by a single introduction event from a genetically depauperate ancestral population.

• Food Science and Preservation
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• v.22 no.6
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• pp.851-858
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• 2015

This study was designed to improve the sensory characteristics and mitigate the bitter taste of Platycodon gradiflorum. It was aimed at investigating the qualitative properties of fermented P. gradiflorum after repeated steaming and drying treatments. P. gradiflorum was heated for 2 hr at $95^{\circ}C$, being the first and third treatments compared afterwards. Lactobacillus plantarum, at a concentration of 10%, was used as starter culture. As a result, the third steaming process and the addition of starter improved the physical and chemical properties of P. gradiflorum i.e., crude saponin and total polyphenol contents increased significantly. Moreover, P. gradiflorum steamed three times and fermented by L. plantarum showed the higher overall preference score. Our results indicated that the three-time steaming and drying was an effective manufacturing process for the production of high-quality fermented P. gradiflorum. Lactic acid-fermented P. gradiflorum also could have a potential use as a valuable resource for the development of functional products.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.423-423
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• 2013

3~5 족 반도체 물질인 phosphorus 화합물 중 대표적인 InAlP 삼종화합물은 작은 굴절률, 큰 밴드갭, GaAs와 lattice 일치 때문에 큰 주목을 받고 있고, p-type high electron mobility transistors(p-HEMT), laser diodes 등의 고속 전자소자 및 광전 소자에 응용이 가능한 매우 중요한 물질이다. 최적의 소자 응용기술을 위해서는, 정확한 광물성 연구가 수행되어야 하지만 InxAl1-xP 화합물에 대한 유전율 함수 및 전자전이점 등의 연구는 미흡한 실정이다. 이에 본 연구에서는 1.5~6.0 eV 에너지 영역에서 각기 다른 In 조성비를 갖는 InxAl1-xP 화합물의 가유전율 함수 ${\varepsilon}={\varepsilon}_1+i{\varepsilon}_2$와 전자전이점 데이터를 보고한다. GaAs 기판 위에 molecular beam epitaxy (MBE)를 이용하여 InxAl1-xP (x=0.000, 0.186, 0.310, 0.475, 0.715, 0.831, 1.000) 박막을 성장하였고 타원편광분석기를 이용하여 유전율 함수를 측정하였다. 또한 실시간 화학적 에칭을 통하여 시료 표면에 자연산화막을 제거함으로써 순수한 InAlP의 유전율 함수를 측정할 수 있었고, 측정된 유전율 함수를 이차미분하여 In 조성비에 따른 전자전이점을 얻을 수 있었다. 얻어진 전자전이점 값을 이용하여 linear augmented Slater-type orbital method (LASTO) 를 통해 이론적 전자 밴드 구조 계산을 하였고, 이를 바탕으로 $E_0$, $E_1$, $E_2$ 전이점 지역의 여러 전자전이점($E_1$, $E_1+{\Delta}_1$, $E_0'$, $E_0'+{\Delta}_0'$, $E_2$, $E_2'$)의 특성을 정의할 수 있었고, $E_0'$과 $E_2$ 전이점의 에너지 값이 In 조성비가 증가함에 따라 서로 교차함을 발견할 수 있었다. 타원 편광 분석법을 이용한 유전율 함수 및 전자전이점 연구는 InAlP의 광학적 데이터베이스를 확보하는 성과와 더불어 새로운 디바이스 기술 및 광통신 산업에도 유용한 정보가 될 것이다.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.23-23
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• 2003

It has been suggested that the impairment of smooth muscle cell (SMC) function by alterations in the $Ca^{2+}$-activated $K^{+}$ ( $K_{Ca}$ ) channels accounts for the reduction in coronary reserve during left ventricular hypertrophy (LVH). However, this hypothesis has not been fully investigated. The main goal of this study was to assess whether the properties of $K_{Ca}$ channels in coronary SMCs were altered during LVH. New Zealand white rabbits (0.8-1.0 kg) and Sprague-Dawley rats (300-400 g) were randomly selected to receive either an injection of isoproterenol (300 $\mu\textrm{g}$/kg body weight) or an equal volume of 0.9％ saline (1 mL/kg body weight). The animals developed LVH 10 days after injection. In patch-clamp experiments, the unitary current amplitude and open probability for the $K_{Ca}$ channels were significantly reduced in LVH patches compared with control patches. The concentration-response curve of the $K_{Ca}$ channel to [C $a^{2+}$]$_{i}$ was shifted to the right. Inhibition of the $K_{Ca}$ channels with TEA was more pronounced in LVH cells than in the control cells. The whole-cell currents of $K_{Ca}$ channels were reduced during LVH. Western blot analysis indicated no differences in $K_{Ca}$ channel expression between the control and LVH coronary SM membranes. In contraction experiments, the effect of a high $K^{+}$concentration on the resting tension of the LVH coronary artery was greater than on that of the control. The effect of TEA on the resting tension of the LVH coronary artery was reduced as compared with the effect on the control. Our findings imply a novel mechanism for reduced coronary reserve during LVH.ing LVH.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.77-77
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• 2018

미역의 뿌리부분인 미역귀에는 알긴산과 후코이단 성분이 풍부하고 고혈압과 당뇨등과 같은 성인병을 예방하는데 도움이 된다. 후코이단은 미역과 다시마 같은 갈조류에서 추출된 천연물질로 특히 면역력을 활성화하고 항암작용으로 잘 알려져 있다. 알긴산 등 유용성분이 함유된 것으로 알려진 미역귀의 유용성분을 분석하여, 향후 미역귀를 활용한 제품개발의 기초자료를 제공하고자 본 연구를 수행하였다. 본 연구에 사용된 미역귀는 2015년 12월 완도 금일수산에서 제공받아 연구재료로 활용하였다. AOAC방법에 따라 분석한 미역귀의 일반성분은 수분이 대부분을 차지하였으며, 조섬유와 가용성 무질소물 함량이 높게 나타났다. 이는 시료로 사용한 미역귀가 수확 후 바로 냉동보관 되어서 수분함량이 높은 것으로 보여진다. 유리당은 미역귀 1g에 증류수를 가하여 $60^{\circ}C$에서 4시간 추출 한 후, 원심분리(3,000 rpm, 30 min)하여 $0.45{\mu}m$ membrane filter (Millipore Co., USA)로 여과한 여액을 HPLC (High Performance Liquid Chromatography)를 이용하여 분석한 결과, 미역귀의 유리당은 Galactose 1종만이 검출되었다. 미역귀의 구성아미노산과 유리아미노산은 $0.45{\mu}m$ membrane filter로 여과하여 얻은 여액을 일정량 취하여 AccQ-Tag 시약을 사용하여 유도체화 시킨 후 HPLC로 분석하였다. 미역귀의 구성아미노산은 glutamic acid, aspartic acid, alanine, lysine, threonine, valine, arginine 순으로 높은 함량을 나타내었으며, 유리아미노산은 glutamic acid, alanine, threonine, arginine, lysine 순으로 높은 함량을 나타내었다. 미역귀의 유리아미노산함량은 표고에 비하여 현저히 낮은 함량이 나타났으며, 주요아미노산은 해조류의 풍미를 대표하는 아미노산인 glutamic acid와 alanine으로 나타났다.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.2
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• pp.78-86
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• 2004

Recently GPS and mobile GIS technologies based on LBS(location based service) have played an important role as DSS(decision supporting system) for domestic forest fire extinguishment policies. In this study forest fire extinguishments information management system based on mobile GIS technique was designed to seize the exact location on wireless network so that it helps to guide the safe and efficient extinguishments affairs and provide the extinguishments environment toward ground fighting teams and the central forest government in real time. Moreover, possibly to operate this system, the foundation technologies by the name of '.gci' such as the spatial data compression method, the spatial data transmission method over wireless network and the spatial analysis interface on PDA should be mainly considered. Especially, in this study the spatial data compression method having high compression rate from 51% to 62% for each polygon, line, and point data, without the loss of data was developed.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.1
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• pp.87-98
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• 2012

A river boundary is defined as the intersection between a main stream of a river and the land. Mapping of the river boundary is important for the protection of the properties in river areas, the prevention of flooding and the monitoring of the topographic changes in river areas. However, the utilization of the ground surveying technologies is not efficient for the mapping of the river boundary due to the irregular surfaces of river zones and the dynamic changes of water level of a river stream. Recently, the spatial information data sets such as the airborne LiDAR and aerial images are widely used for coastal mapping due to the acquisition of the topographic information without human accessibility. Due to these advantages, this research proposes a semi-automatic method for mapping of the river boundary using the spatial information data set such as the airborne LiDAR and the aerial photographs. Multiple image processing technologies such as the image segmentation algorithm and the edge detection algorithm are applied for the generation of the 3D river boundary using the aerial photographs and airborne topographic LiDAR data. Check points determined by the experienced expert are used for the measurement of the horizontal and vertical accuracy of the generated 3D river boundary. Statistical results show that the generated river boundary has a high accuracy in horizontal and vertical direction.

• IMMUNE NETWORK
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• v.6 no.2
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• pp.59-66
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• 2006

Background: CM1 (Centrocyte/-blast Marker I) defined by a mAb developed against concanavalin-A activated PBMC, is expressed specifically on a subpopulation of centroblasts and centrocytes of human germinal center (GC) B cells. Burkitt lymphoma (BL) is a tumor consisting of tumor cells with the characteristics of GC B cell. Previously we reported that CM1 ligation with anti-CM1 mAb induced apoptosis in Ramos $(IgM^{high})$ and Raji $(IgM^{low})$ cells. Methods & Results: In the present study, we observed that CM1 ligation with anti-CM1 mAb induced Fas ligand and Fas expression in Ramos cells, but not in Raji cells. Furthermore, anti-Fas blocking antibody, ZB4, blocked CM1-mediated apoptosis effectively in Ramos cells, but not in Raji cells. Increased mitochondrial membrane permeabilization, which was measured by $DiOC_6$, was observed only in Raji cells. In contrast to no significant change of Bax known as pro-apoptotic protein, anti-apoptotic protein Bcl-2 was significantly decreased in Raji cells. In addition, we observed that CM1 ligation increased release of mitochondrial cytochrome c and upregulated caspase-9 activity in Raji cells. Conclusion: These results suggest that apoptosis induced by CM1-ligation is mediated by Fas-Fas ligand interaction in Ramos cells, whereas apoptosis is mediated by down-regulation of Bcl-2 and subsequent decrease of mitochondrial membrane potential in Raji cells.

• Resources Recycling
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• v.8 no.4
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• pp.45-56
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• 1999

The purpose of tlus sludy was to preparc raw material powder for Mn-Zn iclrile, h m mined mill scale and fero-Mn, usins a co-spray roasting process The mill scale and ferra-Mn uscd in this raalins process was rcf~nedb y mesn-ns of a slxc~apl rxcss ~nvolvinm~a te~ialsc ontalning imp~u-ltleso r less than 100 pprn In this study an effeclive spray roaster system. wllich produces fme complex oxide powder, collects produccd ~owder.,m d prcvel~tse ~~llssiooifi HCI gas. was also manufactured. By means of spray~ngp urifcd raw malerial solu~lionl nln a manufacued high tcmpervture rumace. &-ferrite powder and a comnpleu o ~ d e powder of Fe,O; and M,x203 were manufactured. The chmcterlstics of the composllion. surface urca, and p'miicle size dismbulion or the produced powder were exmined. ptoduced powdcr was then ~ m e dwi tli ZnO powder. aid olher addilives of defined cornposnion, and Mn-Zn femite cares werc praiuccil by meuns of Sorlning and closely controlled sintering processes. The magpelic p~oprlieso f c olo~ss, initlal permeability. mauin~u~mnn agnehc flux. coz~civcr orcc and residual magnccic flux for the above cores we,= measured, and fmm Il~ase I-csulls the eflicacy of lhe co-spray roasling pncess to pl.ellare raw material powder lor Mn-Zn ferntc was established