• 천문학회지
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• 제37권5호
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• pp.427-431
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• 2004

We use simulations of large-scale structure formation to study the build-up of magnetic fields (MFs) in the intergalactic medium. Our basic assumption is that cosmological MFs grow in a magnetohy-drodynamical (MHD) amplification process driven by structure formation out of a magnetic seed field present at high redshift. This approach is motivated by previous simulations of the MFs in galaxy clusters which, under the same hypothesis that we adopt here, succeeded in reproducing Faraday rotation measurements (RMs) in clusters of galaxies. Our ACDM initial conditions for the dark matter density fluctuations have been statistically constrained by the observed large-scale density field within a sphere of 110 Mpc around the Milky Way, based on the IRAS 1.2-Jy all-sky redshift survey. As a result, the positions and masses of prominent galaxy clusters in our simulation coincide closely with their real counterparts in the Local Universe. We find excellent agreement between RMs of our simulated galaxy clusters and observational data. The improved numerical resolution of our simulations compared to previous work also allows us to study the MF in large-scale filaments, sheets and voids. By tracing the propagation of ultra high energy (UHE) protons in the simulated MF we construct full-sky maps of expected deflection angles of protons with arrival energies $E = 10^{20}\;eV$ and $4 {\times} 10^{19}\;eV$, respectively. Accounting only for the structures within 110 Mpc, we find that strong deflections are only produced if UHE protons cross galaxy clusters. The total area on the sky covered by these structures is however very small. Over still larger distances, multiple crossings of sheets and filaments may give rise to noticeable deflections over a significant fraction of the sky; the exact amount and angular distribution depends on the model adopted for the magnetic seed field. Based on our results we argue that over a large fraction of the sky the deflections are likely to remain smaller than the present experimental angular sensitivity. Therefore, we conclude that forthcoming air shower experiments should be able to locate sources of UHE protons and shed more light on the nature of cosmological MFs.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.342-342
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• 2017

Rice seeds are a home to endophytic bacterial communities which serve as a source of the plant's endophytes. As rice undergo physiological and adaptive modifications through cross breeding in the process of attaining salinity tolerance, this may also lead to changes in the endophytic bacterial community especially those residing in the seeds. This study explores the community structure of seed bacterial endophytes as influenced by rice parental lineage, genotype and physiological adaptation to salinity stress. Endophytic bacterial diversity was studied through culture dependent technique, cloning and Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis. Results revealed considerably diverse communities of bacterial endophytes in the interior of rice seeds. The richness of ribotypes ranges from 5-14 T-RFs corresponding to major groups of bacterial endophytes in the seeds. Endophytic bacterial diversity of the salt-sensitive IR29 is significantly more diverse compared to those of salt-tolerant cultivars. Proteobacteria followed by Actinobacteria and Firmicutes dominated the overall endophytic bacterial communities of the indica rice seeds based on 16S rDNA analysis of clones and isolates. Community profiles show common ribotypes found in all cultivars of the indica subspecies representing potential core microbiota belonging to Curtobacterium, Flavobacterium, Enterobacter, Xanthomonas, Herbaspirillum, Microbacterium and Stenotrophomonas. Multivariate analysis showed that the bacterial endophytic community and diversity of rice seeds are mainly influenced by their host's genotype, physiological adaptation to salt stress and parental lineage.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 추계종합학술대회
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• pp.661-664
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• 2003

최근 네트워크 환경에서 보안과 속도는 항상 trade-off가 존재한다. 최근에 개발된 보안 프로세서들은 성능이 매우 향상되고, 많은 부분의 보안 관련 알고리즘이 하드웨어로 구현되어 있다. 이런 고속 보안 프로세서는 매우 큰 대역폭을 요구하는 현 네트워크 보안 솔루션 장비 개발에는 필수 요소가 된다. 본 논문에서는 10 Giga급 VPN 장비의 설계 및 구현에 대해서 기술하고자 한다. 본 시스템에서는 Cavium사의 Nitrox-II 프로세서를 사용하여 10 Giga를 구현하였고, 두개의 SPI-4.2 인터페이스와 PCI 인터페이스를 지원한다. 지원하는 암호 알고리즘은 상용 VPN 장비와의 호환성을 위하여 상용 VPN 장비에서 사용되는 암호 알고리즘은 모두 지원되며 및 국내에서 개발된 SEED 알고리즘도 지원한다. IPsec 및 SSL 프로토콜을 지원하고, 고속 처리에 유리한 In-Line 구조 및 NPU(Network Processor Unit)의 활용도에 유리한 Look-Aside 구조 모두를 지원하도록 설계하였다.

• 한국작물학회지
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• 제48권
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• pp.65-71
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• 2003

Sesame seed are one of the oldest oil-bearing crops known to man. Not only are they nutritious, they are physicologically beneficial. Because of these properties, the promotion of sesame as a crop is set to increase from now on. The lignan component of sesame, which has an antioxidative function, varies considerably. In addition, the seeds remain viable for longer than other crops. At low temperature, it has been reported that the seed remain viable for up to thirty years. This is due to the lignan content of the seeds. In the last twenty years, the mysteries of the natural chemistry of sesame seeds have been unravelled one by one. Up to now, the lignan component has been found to have an $\alpha$-tocopherol synergist effect, an anti-aging effect, a cancer suppressing effect, a hypertension reduction effect, an effect on the promotion of liver function, an effect on the control of the ration of unsaturated fat, and an effect on the synthesis of unsaturated fatty acids. The lignan component of sesame does not simply have an anti-oxidant function, but has diverse recently discovered physiological uses which make the study of lignan highly rewarding.

• 생약학회지
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• 제37권4호
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• pp.290-293
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• 2006

Phytochemical investigation of the seed extract of Nelumba nucifera Gaerth (Nymphaeaceae) resulted in the isolation of a plant hormon, dihydrophaseic acid (1), a abscisic acid derivative. The chemical structure of 1 was elucidated by 2D-NMR spectroscopic analysis, COSY, DEPT, HMQC and HMBC.

• 한국광학회지
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• 제8권5호
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• pp.438-442
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• 1997

본 연구에서는 InGaAsP/InP 액상결정성장에 있어서 성장용액의 불안정성이 성장에 미치는 영향을 조사하여 보았다. 성장용액의 불안정을 완화시킬 수 있는 구조의 흑연보트를 제작하여 성장을 행하여 본 결과 각층의 균일도를 향상시킬 뿐만 아니라 성장층간의 두께 편차를 동시에 줄일 수 있었으며, 성장두께와 두께편차를 각각 1/2, 1/3 이상 줄일 수 있었고, 최소 성장두께 80.angs. 이하의 결과를 얻었다. 그리고 성장용액의 안정도 측면에서 2상용액법에 사용되는 InP seed에 의한 영향을 조사한 결과, 단결정 InP 2상용액법의 경우가 다결정 InP에 비해 우수한 성장특성을 가짐을 확인할 수 있었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제14회 학술발표회 논문개요집
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• pp.41-41
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• 1998

Rare earth metal films have been used as a buffer layer for growing ferroelectric t thin film or a seed layer for magnetic multilayer. But when it was deposited on s semiconductor substrates for the application of magneto-optic (MO) storage media, it i is difficult to exactly measure magnetic cons떠nts due to shunting current, and so it n needs to grow metal films on insulator substrate to reduce such effect. Recently, it w was reported that ultra-thin Pt layer were epitaxially grown on A12O:J by ion beam s sputtering in 비떠 high vacuum and it can be used as a seed layer for the growth of C Co-contained magnetic multilayer. In this stu$\phi$, Pt thin film were epi떠xially grown on AI2D3 ($\alpha$)OJ) by RF magnetron s sputtering. The crystalline structure was analyzed by transmission electron microscope ( (TEM) and Rutherford Back Scattering (RBS)/Ion Channeling. In TEM study, Pt was b believed to be twinned on AI잉3($\alpha$)01) su$\pi$ace about Pt(ll1) plane.Moreover, RBS c channeling spectra showed that minimum scattering yield of Pt(111)/AI2O:J(1$\alpha$)OJ) was 4 4% and Pt(11J)/AI2D3($\alpha$)OJ) had 3-fold symmetry.

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1289-1293
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• 2007

Persicaside has been isolated as a new alkaloid natural compound from a methanol (EtOA)-soluble extract of Prunus persica seed. It was purified by a combination of chromatographic techniques and recrystallization. The structure of Persicaside was determined by extensive NMR experiments and mass ppectroscopic data. It inhibited nitric oxide (NO) and prostaglandin E2 (PGE2) production via suppression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2 expression in rat osteoblast sarcoma cells (ROS 17/2.8) in concentration-dependent manner whereas it spares the COX-1 enzyme activity.

• Food Science and Biotechnology
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• 제18권3호
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• pp.689-693
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• 2009

Germination is well-known to enhance the digestibility, functionality, and palatability of plant seeds. To examine the functionality of germinated-safflower seed (GSS), proliferative and differentiative effects of GSS extract on the mouse calvarial bone cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolinbromide (MTT) assay and alkaline phosphatase activity, respectively. Water extract of GSS increased dose-dependently proliferative and differentiative effects on calvarial bone cell, and its effects were stronger than those of ungerminated-safflower seeds (UGSS) extract. One major component was isolated from GSS extract by a series of purification procedure of solvent fractionation, Diaion HP-20, and Sephadex LH-20 column chromatographies. Its chemical structure was identified as trachelogenin (TC) by nuclear magnetic resonance (NMR) and mass spectrometry (MS) spectral analysis. Trachelogenin showed significant proliferative (125.7%) and differentiative (132.1%) effects on calvarial bone cells at $10^{-8}M$, and its effects were significantly higher than those of $17{\beta}-estradiol\;(E_2)$. TC was found to be a major active compound responsible for high proliferative and differentative effects of the water extract of GSS. Therefore, these results suggest that TC in GSS may be useful as potential therapeutic agent for the prevention and treatment of bone loss.

• 센서학회지
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• 제19권3호
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• pp.202-208
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• 2010

This study examined the dependency of crystalline orientation and electric properties of sol-gel PZT film on hydrolysis, a $PbTiO_3$ seed layer and a concentration of sol-gel solution. The PZT thin films were prepared by using 2-Methoxyethanol-based sol-gel method and spin-coating on Pt/Ti/$SiO_2$/Si substrates. The 1-${\mu}m$-thick PZT films were coated and then fired in a furnace by direct insert method. The highly (111) oriented PZT film of pure perovskite structure could be obtained. We could control the degree of orientation by various parameters such as hydrolysis, a $PbTiO_3$ seed layer and a concentration of sol-gel solution. The highest measured remanent polarization, dielectric constant and piezoelectric coefficient are $24.16\;{\mu}C/cm^2$, 2808, and 159 pC/N, respectively.