• Tunnel and Underground Space
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• v.5 no.1
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• pp.57-69
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• 1995

"수갱공사의 기술적 문제에 대해서(ll)"에서 4가지 특성중 굴하용 권양기의 용량을 결정하는 지표가 되는 한계심도의 결정, 대형 수갱 또는 출수가 많은 경우 폭약의 불발 사고를 방지하는 방법을 다루었으며, 금회에는 수갱의 출수문제를 검토하기로 한다. 검토하기로 한다.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 1995.03a
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• pp.220-238
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• 1995

수갱공사의 기술적 문제에 대해서 (II)에서 4가지 특성중 굴하용 권양기의 용량을 결정하는 지표가 되는 한계심도의 결정, 대형 수갱 또는 출수가 많은 경우 폭약의 불발사고를 방지하는 방법을 다루었으며, 금회에는 수갱의 출수 문제를 검토하기로 한다. (중략)

• Journal of the Korean Society of Combustion
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• v.5 no.1
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• pp.31-41
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• 2000

A numerical study was conducted to investigate the combustion phenomena of regular start and unstart processes based on ISL#s RAMAC 30 experiments with different diluent amounts in a ram accelerator. The initial projectile launching speed was 1800m/s which corresponded to the superdetonative speed of the stoichiometric $H_2/O_2$ mixture diluted with $5CO_2\;or\;4CO_2$. In this study, it was found that neither shock nor viscous heating was sufficient to ignite the mixture at a low speed of 1800m/s, as was found in the experiments using a steel-covered projectile. However, we could succeed in igniting the mixtures by imposing a minimal amount of additional heat to the combustor section and simulate the regular start and unstart processes found in the experiments with an aluminum-covered projectile. The numerical results matched almost exactly to the experimental results. As a result, it was found that the regular start and unstart processes depended on the strength of gas mixture, development of shock-induced combustion wave stabilized by the first separation bubble, and its size and location.

• Aerospace Industry
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• v.50
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• pp.18-21
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• 1997

표류하던 중형항공기사업에 새바람이 불었다. 중국과의 협상결렬과 포커사의 인수불발로 답보상태에 빠져있던 중형기사업조합은 그동안 대안사업을 추진한 결과 지난 97년 4월 11일 유럽의 지역간 항공기 제작업체인AI(R)사와 항공기국제공동개발에 대한 양해각서(MOU)를 체결하고 올 하반기부터 본격적으로 사업을 추진키로 했다. 본 고에는 그동안 AI(R)사의 선정과정과 배경 그리고 협상내용을 살펴보기로 한다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.4
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• pp.482-486
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• 2006

This study was conducted to evaluate the effect of green tea powder on the sensorial quality of Chungkookjang. The results showed that the addition of Ttuck-cha or Ooreung-cha green tea powder was not appropriate for the fermentation of Chungkookjang. The results of sensory evaluation approved that the addition of Choi-cha or Powder-cha green tea powder reduced the off-odor of Chungkookjang. Therefore, Choi-cha and Powder-cha could be used as the effective natural additives for the improvement of the sensorial quality of Chungkookjang.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.5
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• pp.518-525
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• 2012

In this study, the feasibility of hyperspectral reflectance imaging technique was investigated for the discrimination of viable and non-viable lettuce seeds. The spectral data of hyperspectral reflectance images with the spectral range between 750 nm and 1000 nm were used to develop PLS-DA model for the classification of viable and non-viable lettuce seeds. The discrimination accuracy of the calibration set was 81.6% and that of the test set was 81.2%. The image analysis method was developed to construct the discriminant images of non-viable seeds with the developed PLS-DA model. The discrimination accuracy obtained from the resultant image were 91%, which showed the feasibility of hyperspectral reflectance imaging technique for the mass discrimination of non-viable lettuce seeds from viable ones.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.418-419
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• 2003

종래의 케도회로를 사용하지 않는 무선통신기반의 이동폐색방식 열차제어시스템에서는, 궤도회로에 의한 폐색구간를 기반으로 하는 종래의 연동제어논리를 더 이상 사용할 수 없게 된다. 이와 같이 궤도회로를 사용하지 않고 역구내에서의 진로제어를 수행하기 위한 연동논리를 구축하기 위하여, 역구내에서, 장내 및 불발과 분기기 구간 위치에서 가상 섹션을 두어서 열차의 진입 유무를 고정폐색방식으로 치환하고, 진로관리와 연쇄, 선로전환기 제어와 쇄정, 신호제어등의 연동논리를 구축하는 방안을 제시하였다.

• Journal of Sericultural and Entomological Science
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• v.44 no.2
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• pp.56-58
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• 2002

An autotetraploid, Sawonppong 28 was derived from a thick-leaf and highly productive mulberry variety, Huyeoprok, by colchicine solution treatment on growing point and its characteristics were as follows. The number of somatic chromosomes of the derived variety was 2n=56 of an autotetraploid and green tip sprouting stage was medium budding variety with triangular oval shape and thick leaves contained rich chlorophyll. The length of branches was comparatively short and the number of branches was also small. However the branches were thick and non-budding length percentage at basal part of branch was high and cold hardiness was weak.

• Journal of Sericultural and Entomological Science
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• v.4
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• pp.27-31
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• 1965

The aim of this work was to investigate how the mulberry shoots grew well when the mulberry branches were cut down, in hight, 1/3, $\frac{1}{2}$ and 2/3 of them, respectively, just before the Spring budding. The results obtained are as follows: 1. The rate of un-sprouted buds decreased sharply down as much as half of the control if the mulberry branches were cut off. The treatment, 1/3, was best one of various cut down sizes and the un-sprouted buds concentrated on the lower parts of the branches. 2. Even though the branches were cut down, at first it seemed flat to accelerate the sprouting of buds, but rather to have a tendency to become late. The speed of leaf growth, however, became faster after the sprouting. It took 7~9 days from the beginning of buddings to the 5th full grown leaf, and.7 days for the shortest one in the treatment, 2/3, when compared with 16 days of the control. 3. If the branches were cut down, the growth of the new sprouts was accelerated. For 45 days (on 5th of May to on 10th of June), therefore. the shoots had grown up to 1.6～2.5 times of the control, 34cm long. The shoots of which the branches were cut down at 2/3 of them were longest (83cm). Furthermore. the speed of shoot growth of cut-down branches was faster than that of the control. 4. In the increased rate of the number of the mulberry leaves, there was not significant difference between the control and the treatments. 5. The total amount of shoot growth showed considerably much more in the treatments than in the control. The successing growing shoots of treatment, 2/3 were little in a number but longest per one shoot in mean shoot length. 6. It seems to be much available that we may cut down branches at 2/3 of them in order to get the scions for the cutting as soon as possible.

• Explosives and Blasting
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• v.34 no.4
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• pp.19-27
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• 2016

Much care should be taken when electric caps are used in blast site than when non-electric initiation systems are used. This is because electric caps can cause premature firing or misfires if stray currents of high magnitude flow into the blasting circuit. If the rock has higher electrical conductivity or lower electrical resistivity, such risks will be increased because the rock will provide more passages for the stray currents to flow into the blasting circuit. In this study, several rock samples obtained at a blast site were tested for electrical resistivity to decide whether electric caps could be used or not in the site. The measured electrical resistivity was $39{\sim}47{\Omega}{\cdot}m$ for the rock samples that had a higher content of metal sulfides. Contrary, the resistivity was $15000{\sim}21000{\Omega}{\cdot}m$ for ordinary rocks. Especially, in the case of the rock of electric resistivity of $39{\Omega}{\cdot}m$, only 2-V electric potential enables a stray current to flow through the rock of 1-m length, which can cause the premature firing of a detonator whose initiation current is 0.4 A. This result shows that electric initiation system should not be used in the site because rocks containing much amount of metal sulfides are widely distributed there.