• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.3
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• pp.296-304
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• 1998

A design method of an electromagnetic wave absorber with ferrite fins in the second layer, which has very wide band frequency characteristics and is used for single-polarized wave absorption such as TV wave etc, has been designed. To examine the effectiveness of the Equivalent Material Constants Method$(EMCM)^{[1]}$ which is approximate method, the effective complex permittivity calculated by the Hashin-Strikman formulas and the EMCM are compared. Since, furthermore, the reflectivities by the EMCM in space and the FDTD method in an rectangular waveguide agreed well each other, it has been confirmed that the proposed electromagnetic wave absorber has excellent absorption characteristics in the frequency range of 30 MHz to 5830 MHz. Thus, it can be concluded that the EMCM is usefull to design and analyze the electro-magnetic wave absorber proposed here.

• Korean Journal of Microbiology
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• v.27 no.3
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• pp.221-224
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• 1989

Amylolytic filamentous fungus, Aspergillus oryzae and nonamylolytic sugar fermentable yeast, Saccharomyces cerevisiae were fused by protoplast fusion in order to develope microorganisms having their intergrated function. Aminoacid auxotrophic properties were used as a genetic marker of protoplast fusion, and 35% PEG 4000 was used as a fusogenic agent. Complementation frequengy of fusion was $4.6\times 10^{-6}$ Obtained fusants showed the morphology of yeast strains, the amylase activity and the ethanol productivity. Among the properties of the fusants, morphology and prototrophic property were sustained stably but their ethanol productivity from starch was reduced. Although fusant strains had 0.5-fold ethanol productivity compared to that of S. cerevisiae in glucose medium, they produced ethanol from strach by direct fermentation.

• Proceedings of the Korea Information Processing Society Conference
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• 2019.10a
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• pp.946-949
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• 2019

한 벌의 한글 글자체를 만드는데 일반적으로 많은 제작 비용과 시간이 소요된다. 따라서 폰트 제작의 어려움을 덜기 위해, 사용자가 대표 글자들을 입력하면 그 글자들의 디자인 특성을 딥러닝 기술을 이용하여 학습한 모델이 나머지 글자들을 자동 생성해주는 시스템 구축한다면 폰트 제작이 훨씬 용이해질 뿐만 아니라 저작권 문제로부터 자유로워질 것이다. 이와 관련된 선행연구를 실행하고 분석해 본 결과 데이터 전처리 과정에서 글자가 잘리거나 크기가 맞지 않아 제대로 된 데이터셋이 구축되지 않는 문제가 있음을 발견하였다. 본 논문에서는 이러한 문제를 해결하기 위해 템플릿에서 자동적으로 글자영역을 추출하고 이미지를 보정하는 전처리 과정과 함께 기존 모델에서 새로운 필터를 추가하여 학습 성능을 높이는 방법을 제안한다. 이를 통해 기존 연구에서 측정된 손실값을 낮춘 결과를 확인했으며 결과적으로 실제 글자체와 더욱 유사한 사용자 맞춤형 글자체를 제공할 수 있을 것이다.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.335-339
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• 2003

Several experiments were carried out to transfer LEAFY gene to Dendranthema grandiflora 'Shuho-no-chikara' by Agrobacterium LBA4404 carrying pSK109 encoding LEAFY gene. Kanamycin 10mg/L was used in first selection medium, and 20mg/L in the second one. Co-culture for 3 days was more effective in increasing transformation efficiency than that for 7 days. The transformation efficiency by Agrobacterium LBA4404 carrying pSK109 encoding LEAFY gene was about 2.8％ until the second selection, but only 0.13％ of shoots (two plants) was confirmed as a transgenic plants in Southern analysis. The escape of putative transformants was occured seriously in the process of selections, PCR analysis for confirming of neomycin phosphotransferaseII (npt II), and Southern analysis for LEAFY gene. One transgenic plant appeared 7 days'early flowering in field.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.379-383
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• 1996

The ultrastructure of the compound starch granules and the protein bodies of Odaebyeo rice of early matured variety were examined by light microscope and electron microscope. The endosperm cell appealed rectangular or octangular shape on the cross section. The thickness of cell wall containing of membraneous materials was about $0.5\;{\mu}m$ in diameter. The starch cell was filled compactly with globular or oval shaped compound starch granules with the size of $20{\sim}25\;{\mu}m$ in diameter. The compound starch granules were consisted of central core starch granule and concentrical $2{\sim}3$ layers of starch granules. The average thickness of the starch granules were about $5\;{\mu}m$. Most protein bodies were found in the aleurone layer The globular protin bodies were scattered near the compound starch granules and $2.5{\sim}3\;{\mu}m$ in diameter. The protein bodies composed of central electron dense materials and peripheral electron loose materials in limiting membrane.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.1
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• pp.41-52
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• 2021

During atmospheric ascent of a launch vehicle, airborne acoustic loads act on the vehicle and its effect becomes pronounced at transonic speed. In the present study, acoustic loads acting on a hammerhead launch vehicle at a transonic speed have been analyzed using ��-ω SST based IDDES and the results including mean Cp, Cprms, and PSD are compared to available wind-tunnel test data. Mesh dependency of IDDES results has been investigated and it has been concluded that with an appropriate turbulence scale-resolving computational mesh, the characteristic flow features around a transonic hammerhead launch vehicle such as separated shear flow at fairing shoulder and its reattachment on rear body as well as large pressure fluctuation in the region of separated flow behind the boat-tail can be predicted with reasonable accuracy for engineering purposes.

• The Journal of Korean Institute for Practical Engineering Education
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• v.3 no.1
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• pp.51-55
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• 2011

In this paper, it introduce how to operate the design 1 credit (one hour), containing in the experimental courses (2 credits and 3 hours) of "Basic Electronic Circuit Design and Experiment" and "Advanced Electronic Circuit Design and Experiment" in junior grade of Information & Control Engineering Advanced Course in Hankyong National University. The effective procedures, results, and improvements to operate the design 1 credit (one hour) in combination with the experimental one credit (2 hours), according to the engineering accreditation system, are introduced. To learn an effective design method, students have to learn completely the design courses according to a system diagram for completing design courses.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.113-116
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• 2001

Chromosomal variation was investigated in the female and male somaclones regenerated from the leaf segment culture of Rumex acetosa L. Difference in phenotype depending on the sexuality was not observed. In female somaclones, 21 among 25 somaclones carried the same chromosome complements (2n＝14) with wildtype and others were tetraploids (2n=28), Considerable chromosomal variation was found in male somaclones. Only 4 among 20 somaclones carried normal chromosome number (2n=15) and 13 somaclones were aneuploids.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.4
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• pp.328-333
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• 1984

Variation in ploidy level of regenerated plants from rice anthers and effective diploidization methods of haploid plants were studied to obtain basic information in rice breeding through anther culture. In a total of 574 plants derived from anther culture using 14F$_1$ hybrids as materials, there were 49.7% haploids, 48.6% diploids and 1.7% polyploids, respectively. The frequency of haploids in Japonica/Indica crosses was 60.6%, and that of Japonica/Japonica crosses was 43.0% in average. Inclusion of 2.4-D or NAA as phytohormone may increase the frequency of haploids, but kinetin may increase the frequency of diploids. The rate of auto-diploidization by tiller separation of haploid plants showed 8.2% in average. The rate of diploidization by leaf-sheath injection of colchicine showed 18.8% in average. Morphological characters of haploids plants showed that 64.6% in culm length, 63.4% in panicle length, 68% in flag leaf length, and 74.4% in flag leaf width compared to diploid plants. These apparent morphological differences will contribute to identify the ploidy of plants derived from rice anther culture.

• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.299-310
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• 2016

The Stele for Buddhist Monk Wonjong at Godalsa Temple Site was destroyed a long time ago. Only the tortoise-shaped pedestal and the ornamental capstone in the form of a hornless dragon remain at the site and the broken stele body is stored at the National Museum of Korea today. The stele is made of two kinds of rocks that are coarse-grained biotite granite for the pedestal and the capstone, and fine-grained biotite granite including hornblende assemblages and feldspar phenocrysts for the stele body. The coarse-grained biotite granite of the pedestal and capstone showed same magnetic susceptibility and lithological characteristics with biotite granite outcrops in Yeoju area, whereas the fine-grained granite of the stele body did not. To find a provenance of the stele body stone, we investigated Korean granites in terms of magnetic susceptibility, lithology and old recordings about construction process of the stele. As a result, Haeju granite is the most likely to be a cognate rock of the stele body stone as it has same texture and lithological characteristics like color, hornblende assemblages, mineral composition and magnetic susceptibility. It is imported from Haeju (North Korea) to South Korea via China commercially, and the most suitable for a replica stone of the stele body.