• Nuclear Engineering and Technology
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• v.3 no.3
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• pp.129-140
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• 1971

Two laboratory-melt heats of 3.25 silicon-iron were made and processed according to a normal commercial practice. Some of the important processing variables that were studied in relation to secondary recrystallization and texture development were contents of manganese and sulfur, heat-treatments after hot-rolling that were used to achieve different hot-rolled microstructures, and amounts of second cold-reduction. The main effort of the present study was directed toward elucidating the relationships among the amount of second cold-reduction, activation energies associated with secondary recrystallization and texture development. The specimens that had been cold-reduced 10% exhibited only grain growth by strain-induced grain boundary migration and did not exhibit secondary recrystallization. Secondary recrystallization did rot appear to completely occur in the 30% cold-reduced specimens, although the nucleation for secondary recrystallization was observed. The second cold-reduction in an amount of 50% was shown to be the optimun for secondary recrystallization and texture development by subsequent processing.

• The Journal of the Acoustical Society of Korea
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• v.17 no.8
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• pp.68-72
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• 1998

본 논문에서는 기존의 DPCM에 의한 압축방법보다 더 낮은 비트율을 갖는 압축방 법을 제안한다. 각 화소의 예측오차 값은 DPCM방법에 의해 양자화되고, 양자화된 예측오차 의 열은 예측오차의 학습된 열로 구성된 코드북과 비교된다. 비교과정은 벡터양자화 방법과 동일하고, 그 결과 코드북의 주소를 생성한다. 제안된 방법은 DPCM과 동일한 복원 영상의 화질을 보이지만, 더 낮은 비트율을 얻을 수 있다.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.11
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• pp.78-84
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• 1998

Refractive index was matched using the inhomogeneous dielectric layers to enhance the optical transmittance of surface discharge type AC PDP. The transmittance of upper panel which had two index-matched inhomogeneous dielectric layers was measured as 85%, and this result is regarded as 15% better transmittance than that of conventional structure, which is about 70%.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.2049-2053
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• 2007

KModSim은 수자원배분에 관련된 물리적, 수문학적, 제도적, 그리고 행정적인 요구들을 동시에 만족하도록 디자인된 범용 우선순위 목적 선형최적화 모형으로써 자연유3tt입량과 기득 수리권 혹은 기득 저류권 등과 같은 다양한 형태의 저수권 사이의 조화운영이 가능하다. KModSim은 목적함수에 관련된 제약조건의 유연한 설정과 변경이 가능하며, 기존의 최적화 방법과 다르게 유역통합모의에 관련한 모형변수가 모형내에서 자동적으로 생성되도록 프로그램화 되어있다. 본 연구에서는 금강유역내 수자원의 효율적인 운영을 위하여 과거운영자료를 토대로 저수지운영율을 개발하고 시스템단계(system states)를 이용하여 KModSim 네트워크에 운영율을 적용하였다. 금강유역에서 개발한 운영율을 적용하고 모의한 결과 개발된 운영율은 실제저류량을 잘 재현하는 것으로 나타났다. 본 연구에서 개발된 운영율 및 시스템단계 방법은 다중목적 우선순위 선형최적화 모형을 이용하여 유역의 다양한 수자원운영모의에 사용될 수 있을 것으로 기대된다.

• Journal of Sericultural and Entomological Science
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• v.20 no.2
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• pp.40-44
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• 1978

Cerium (IV) ion-initiated graft copolymerizations of acrylonitrile to raw silk were investigated in an effort to carry out sericine-fixation. The change in ceric ammonium nitrate concentration exhibited a maximum in percentage of grafting at 0.003M. Also observed was that the change in nitric acid content in reaction media gave a maximum in percentage of grafting at 0.1M. Percentage of grafting was increased generally with increase in acrylonitrile concentration, reaction time and reaction temperature. Raw silk sericin grafted with acrylonitrile was not de gummed by boiling off test and optimum graft percentage was considered at 20%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.177-181
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• 1985

Aflatoxin production by Aspergillus parasiticus NRRL 2999 with two different levels of inoculum sizes ($10^2$ and $10^6$ spores) was studied on such varieties of soybeans produced in Korea as Bongeui, Hwang Keum, Jangbaek, Danyeop, Jangyeop and Namcheon. With the inoculum size of $10^2$ spores/10 g of soybeans, there were statistically difference (p<0.05) on the production of aflatoxins in the varieties of soybeans. The variety of Namcheon produced 7 times higher amount of aflatoxin $B_1$ than that of Bongeui. The variety of Jangyeop produced the highest level of aflatoxin $G_1$ among the varieties employed. Namcheon and Jangyeop were the varieties which supported high amounts of aflatoxins. Much higher levels of aflatoxins were obtained on the soybeans than on rice in general with the inoculum size of $10^2$ spores. With the inoculum size of $10^6$ spores/10 g of soybeans, significantly lower levels of aflatoxins were synthesized by the mold than those with $10^2$ spores. The variety of Namcheon resulted in the lowest production of aflatoxin $B_1$ while Hwangkeum was the variety that produced highest amount of aflatoxin $B_1$. There were no significant differences within the varieties on the production of aflatoxin $G_1$ by the mold except the variety of Hwangkeum. Lower quantities of aflatoxin $B_1$ were produced by the mold en the soybeans than on rice with the inoculum size of $10^6$ spores.

• Korean Journal of Microbiology
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• v.35 no.4
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• pp.270-276
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• 1999

Production of stress shock proteins in Burkholderia cepacia YK-2 in response to the phenoxyherbicide 2,4-dichlorophenoxyacetic acid(2,4-D) as an environmental contaminant was investrigated. The stress schock proteins were synthesized at different 2,4-D concentrations in exponentially growing cultures of B. capacia YK-2. This response involved the production of 43kDa and 41kDa GroEL proteins. The proteins were characterized by SDS-PAGE and Western blot using the anti-DnaK nad anti-GroEL monoclonal antibodies. Total stress shock proteins were analyzed by 2-D PAGE. Survival of B. cepacia YK-2 with time in the presence of different concentrations of 2,4-D was monitored, and viable counts paralleled the production of the stress shock proteins in this bacterium.

• Journal of Korea Multimedia Society
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• v.4 no.3
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• pp.238-246
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• 2001

We have developed the sign-language synthesis system, which can be applied for intelligent terminal equipments, for the purpose of communications between normal people and the hearing-impaired. In the system, we generate the behavior of the sign-language words using CG animation based on Motion-Primitives of the motion observed of each legion of the body in the generation of words, the conventional system was difficult to control the shape of hands and the motions of hands and shoulder, requiring lots of time for the processing. Also it is a big problem to make a large database of sign-language, because it requires over 5,000 words to translate the sign-language. Therefore, in this paper, we propose the new system that is easy to construct the database by using Motion-Primitives, which can make paths of various motions more smooth than conventional systems. We have tested 100 words of the sign-language against the hearing-impaired with the proposed system. As the result of testing by the proposed system, we have earned a good recognition rate with 82%. On the other hand, we had earned the recognition ratio with 76% by using the former system.

• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.136-141
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• 2007

The decomposition of chlorinated methanes including $CCl_4$, $CCl_3H$, and $CCl_2H_2$ was carried out using a thermal plasma process and the characteristics of the process were investigated. The thermal equilibrium composition was analyzed with temperature by Fcatsage program. The decomposition rates at various process parameters including the concentration of reactants, flow rate of carrier gas, and quenching rate, were evaluated, where sufficiently high conversion over 92% was achieved. The generation of main products was strongly influenced by the reaction atmosphere; carbon, chlorine, and hydrogen chloride at neutral condition; carbon dioxide, chlorine, and hydrogen chloride at oxidative condition. The decomposition mechanism was speculated considering the results from Factsage and the identification of generated radicals and ionic species. The main decomposition pathways were found to be dissociative electron attachment and oxidative by radicals formed in a plasma state.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.2
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• pp.139-144
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• 2012

A numerical simulation has been performed to investigate effects of toluene mixing on soot formation in pure ethylene opposed-flow nonpremixed flame. Mixture ratios of toluene were 3%, 5%, 10%, and 20%. Senkin code for 0-D simulation and oppdif code for 1-D simulation based on CHEMKIN III were utilized. 0-D results by senkin showed that concentrations of methyl radicals and benzene were increased with increasing toluene mixture ratio. This implied that the mixing of toluene in pure ethylene diffusion flame produces more PAHs and soot than those of pure ethylene flame. 1-D result of 10 % toluene reaction by oppdif code showed that production rate for H radical was a crucial factor for benzene formation. These results imply that methyl radical, benzene and H radical play a important role on soot formation in diffusion flames.