• Journal of the KSME
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• v.29 no.6
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• pp.573-580
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• 1989

현재 한국의 자동차 공업은 80년대 초반부터 급격한 발전으로 세계의 다른 자동차 생산국으로부 터 경계의 대상이 되고 있다. 그러나 그 내면을 살펴보면 아직도 중요한 기술은 거의 대부분 일 본이나 독일, 미국 등 자동차 선진국의 기술에 의존하고 있으며 특히 엔진 분야는 대부분 외국 기술에 의존하고 있다고 해도 과언이 아니다. 엔진은 자동차 생산원가의 약 30%를 차지하며 자동차의 성능을 좌우하는 경우 기술료 지급은 물론이며 부품구매 선택의 여지가 없어진다. 또한 요즈음과 같이 상품의 수명주기가 짧게 되어 가는 추세 하에서는 시장의 요구에 대처해나가는 엔지니어링 적응력이 부족하게 되면 결국 경쟁성을 상실하게 된다. 그러나 이러한 문제점을 인 식하면서도 80년대 초까지 독자적인 엔진개발을 하지 못했던 원인은 크게 2가지로 분석할 수 있다. 첫째는 한국의 자동차 회사들의 기술 축적의 미약과 둘째는 독자개발의 낮은 투자효율성 이다. 즉 엔진과 변속기를 기술 도입할 때 기술료 지급은 자동차 생산댓수당 5-6만원에 달하지만 엔진과 변속기를 독자개발시의 투자비는 약 300-500억원에 달하므로 간단한 산술적 계산으로는 모델당 100만대를 생산하여야만 투자의 가치가 있는 것으로 보여진다. 물론 위에서 언급한 바와 같은 여러 가지 요인에 의하면 이 숫자보다 훨씬 적은 생산량으로도 경쟁성이 확보될 것으로 예상된다. 이제 한국의 자동차 생산량도 연간 백만 대를 상회하는 수준이며 앞으로도 급격한 양과 질적인 팽창이 기대되고 있는 시점에 자동차 메이커들은 각사 모두 독자적인 고유 엔진 개발을 착수하였으며 일부 회사는 이미 성공을 거두어 양산 준비를 하고 있는 것으로 알고 있다. 그러나 아직도 엔진의 설계부터 양산까지 걸리는 기간이 타 선진 메이커에 비하면 상당히 길며 이로 인해 신제품의 경쟁력 저하가 우려되고 있는 상태이다. 이러한 문제점 해결에 도움을 주기 위해서 학계는 기업체의 기술 개발방향과 전략을 이해하는 것이 필요하다.grightarrow$cn-semistratifiable over$\longrightarrow$semistratifiable over $\alpha$ 2, 어떤 공간이 cn-Semistratifiable over $\alpha$이기 위한 필요충분 조건은 그것이 linearly cushioned cn-pairnet를 갖는 것이다. 3. cn-semistratifiable over $\alpha$의 부분공간 역시 cn-semistratifiabie over $\alpha$ 하다. 4. on-semistratifiable over $\alpha$의 유한개의 적공간 역시 cn-semistratifiabie over $\alpha$한다. 5. 폐 cn-semistratifiable over $\alpha$ 부분공간들의 합공간 역시 on-semistrbtifiable over $\alpha$ 하다. 6. 폐연속 net-cevering 함수에 의하여 cn-semistratifiable over $\alpha$ 성질이 보존된다. 보잘것이 없었고, 현재에도 각 시도별 또는 대학주관의 경시대회가 있으나 거국적인 호응을 받지 못했다. 물론 국제 대회에 참석시키는 것은 엄두도 내지 않았다.로 나타났다. 4. 코코넛과 소나무수피의 경우 암모니아 가스에 대한 흡착 능력은 거의 비슷한 것으로 사료되며, 코코넛의 경우 전량을 수입에 의존하고 있다는 점에서 국내 조달이 용이하며, 구입 비용도 적게 소요되는 소나무수피를 사용하는 것이 경제적이라고 사료된다. 5. 마지막으로 악취제거 미생물균주를 접종한 소나무수피 50%와 펄라이트 30%의 혼합재료를 24시간 동안 장기간 운전 실험을 수행한 결과 암모니아 99.06%, 황화수소 96.61%의 제거

• The Korean Journal of Mycology
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• v.12 no.4
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• pp.153-157
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• 1984

In order to investigate an etiological characteristics of the pepper anthracnose fungus infected with Collectotrichum dematium, this experiment was undertaken. Isolation percent of the fungus was 55.3% from the seed sample of Jewon and 0.3% from that of Eumsung Kun, according to seed health blotter method. Although the acervulus was similar to the known two Colletotricum species, C. acutatum and C. gloeosporioides, setae was not only straightly extended above the acervulus, but also shaped as falcate conidia ranging $12{\sim}31.2{\times}2.4{\sim}4.8{\mu}m$. Acervului of the fungus were evenly scattered on the surface of pepper seed coat, and caused seedling blight after seed germination. Pre-and post-emergence seedling blight as well as foliar lesion and fruit rot was confirmed by inoculating conidial suspension. No typical anthracnose sysmptom was obtained from soybean seedlings, welsch onion and spinach seedlings upon inoculation. Therefore, this fungus is said to the undescribed form species of the fungus of pepper in Korea (Colletotricum dematium f. sp. capsicum).

• Journal of the Korean Society for information Management
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• v.22 no.1 s.55
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• pp.47-64
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• 2005

To guarantee the long-term access to digital material, digital preservation needs to be systemized, and detailed investigation on cost elements of digital preservation should be done for the continued support of budget. To meet the needs in this area, this paper categorized the digital preservation cost into direct and indirect cost through deriving common elements used in prior research on this issue. For case analysis, two institutions, representing domestic University Library and National Library of Korea under large-scale digitization currently, are selected to analyze the current status of digital preservation and estimate the preservation cost. The case analysis shows the systematic preservation function should be performed to guarantee the long-term access digital material, even though a basic digital preservation is currently conducted. It was projected that the digital preservation cost for the two libraries, accounting for $11.8\%$ and $8.6\%$ of digitization cost, respectively, should be injected every year. However, the estimated figures are very conservative, because the cost for estimating the preservation function, such as installing digital repository and producing meta data, was excluded in the estimation. This proves that digital preservation is a synthetic activity linked directly and indirectly to various activities from production to access of digital object and an essential costs that should be considered from the beginning stage of digitization project.

• Korean Journal of Breeding Science
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• v.51 no.2
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• pp.105-109
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• 2019

'Hwangdaok', a new maize F1 hybrid (Zea mays L.), was developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2016. The high-yielding yellow dent hybrid named 'Hwangdaok' was obtained by crossing between two inbred lines, 'KS203' and 'KS190'. After advanced yield trial in Suwon in 2012, regional yield trial was subsequently carried out to evaluate the growth and yield of 'Hwangdaok' at three different locations from 2014 to 2016. The number of days to silking of 'Hwangdaok' is 76. The plant height is 262 cm and ear height ratio is 51%, which are similar to those of 'Jangdaok'. It has resistance to lodging. The number of ears per 100 plants is 95. The ear length is 21.3 cm and weight of 100 seeds is 34.7 g, similar to those of 'Jangdaok'. It has moderate resistance to southern leaf blight (Bipolaris maydis) and European corn borer (Ostrinia nubilalis). The grain yield (10 ton/ha) of 'Hwangdaok' is 6% higher than that of 'Jangdaok'. The seed production rate of 'Hwangdaok' is acceptable due to good synchronization of flowering period during crossing between the seed parent, KS203, and the pollen parent, KS190, in Yeongwol. F1 seed yield was 1.68 ton/ha. 'Hwangdaok' can be a suitable cultivar to plain areas in Korea. (Variety registration No. 7502).

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.4
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• pp.319-327
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• 2010

A nuclear plant ESF ACS simulator was designed, built, and verified to perform experiment related to ESF ACS of nuclear power plants. The dimension of 3D CAD model was based on drawings of the main control room(MCR) of Yonggwang units 5 and 6. The CFD analysis was performed based on the measurement of the actual flow rate of ESF ACS. The air flowing in ACS was assumed to have $30^{\circ}C$ and uniform flow. The flow rate across the HEPA filter was estimated to be 1.83 m/s based on the MCR ACS flow rate of 12,986 CFM and HEPA filter area of 9 filters having effective area of $610{\times}610mm^2$ each. When MCR ACS was modeled, air flow blocking filter frames were considered for better simulation of the real ACS. In CFD analysis, the air flow rate in the lower part of the active carbon adsorber was simulated separately at higher than 7 m/s to reflect the measured value of 8 m/s. Through the CFD analyses of the ACSes of fuel building emergency ventilation system, emergency core cooling system equipment room ventilation cleanup system, it was confirmed that all three EFS ACSes can be simulated by controlling the flow rate of the simulator. After the CFD analysis, the simulator was built in nuclear grade and its reliability was verified through air flow distribution tests before it was used in main tests. The verification result showed that distribution of the internal flow was uniform except near the filter frames when medium filter was installed. The simulator was used in the tests to confirm the revised contents in Reg. Guide 1.52 (Rev. 3).

• Korean Journal of Veterinary Research
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• v.2 no.1
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• pp.1-13
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• 1962

10두(頭)의 홀스타인 자우(仔牛)에 glucagon, insulin 등 홀몬과 reserpine 및 nicotine을 투여(投與)하여 그들이 췌장(膵臟)의 Langerhans 도서(島嶼)에 미치는 세포학적(細胞學的) 영향을 전자현미경(電子顯微鏡)에 의해서 연구하는 도중 거대(巨大)한 크기의 도서(島嶼)를 관찰하였다. 이 거대도서(巨大島嶼)들은 상기(上記)한 약품투여에 영향을 받지 않으며 거의 beta 세포(細胞)들로만 되어 있으므로 보통 크기의 도서(島嶼)들과의 혼동을 피하기 위하여서는 그 분포상태(分布狀態)와 세포학적(細胞學的) 및 조직학적(組織學的) 특징(特徵)을 구명(究明)하는 것이 필요하게 되어 본연구(本硏究)에 착수하였든 것이며 아울러 췌장(膵臟) 각부분(各部分)에 함유되는 Langerhans 도서수(島嶼數)의 평균치(平均値)를 산출(算出)하였다. Langerhans 도서(島嶼)는 편의상 그 크기에 따라서 직경(直徑) $200{\mu}$이하(以下)의 것을 "Regular islets" $200{\sim}500{\mu}$까지의 것을 "Intermediate islets" 그리고 $500{\mu}$ 이상(以上)의 것을 "Giant islets"라 이름지어서 구별하였다. 지금까지 알려진 최대(最大)의 도서(島嶼)는 개에서 관찰된 $333{\mu}$의 도서(島嶼)이었는데 필자는 본연구(本硏究)에서 직경 $1.395{\mu}$에 달하는 것과 기리 $2,700{\mu}$에 달하는 거대(巨大)한 도서(島嶼)들을 관찰하였다. 본연구(本硏究)의 결과(結果)를 요약(要約)하면 다음과 같다. 1. 자우췌장(仔牛膵腸) 50평방(平方)mm 면적(面積)내에 함유되는 Langerhans 도서(島嶼)의 수(數)는 평균(平均) 191개로서 다른 연구자에 의해서 보고된 수치(數値)보다 훨씬 많은 것이었다. 2. 거대도서(巨大島嶼)의 크기는 직경(直徑) $200{\sim}1,400{\mu}$이며 그 분포상태(分布狀態)는 보통 크기의 도서(島嶼)와 마찬가지로 췌장(膵臟)의 십이지장부(十二指腸部) 중간부(中間部) 및 췌장부(膵臟部)의 순서(順序)로 많이 함유되고 있다. 즉 십이지장부(十二指腸部)에는 2% 중간부(中間部) 1.8% 췌장부(膵臟部)에는 0.8%의 거대도서(巨大島嶼)가 함유되어 있으며 직경(直徑) $200{\mu}$이상(以上)의 도서평균치(島嶼平均値)는 1.53%이었다. 3. 중간대(中間大)의 도서(島嶼)와 거대도서(巨大島嶼)들은 거의 beta 세포(細胞)들로서만 되어있음으로 "중간대(中間大) beta 도서(島嶼)" 및 "거대(巨大) beta 도서(島嶼)"라고 각 각 명명하였으며 alpha세포(細胞)들이 있는 경우에는 작은 세포집합체(細胞集合體)를 이루고 도서전반(島嶼全般)에 걸쳐서 산재(散在)한다. 4. 췌장(膵臟)에 함유되고 있는 거대(巨大) beta 도서(島嶼)의 수(數)는 적지마는 보통 크기의 도서(島嶼)와 비교할때 그 용량(容量)은 막대한 것이며 따라서 insulin 분비량(分泌量)도 많을것이므로 우췌장(牛膵臟)의 insulin 분비(分泌)를 연구할 때에는 반듯이 이 사실(事實)을 고려해야 할 것이다. 5. 불규칙한 색상(索狀)의 실질세포(實質細胞)들로된 거대(巨大) beta 도서(島嶼)에는 간질결합조직(間質結合組織)이 풍부하며 그 간질(間質) 속에는 비교적 큰 혈관(血管)과 개재관양(介在管樣) 구조물(構造物)이 들어있다. 거대(巨大) beta 도서(島嶼)는 출생(出生)후 도서내외(島嶼內外)에 산재(散在)하고 있는 외분비도관세포(外分泌導管細胞)들의 증식(增殖)에 의해서 발생(發生)하며 그 크기도 증대(增大)하는 것으로 믿어진다. 6. 거대(巨大) beta 도서(島嶼)의 beta 세포(細胞)들은 현저한 Golgi 장치(裝置)와 비대(肥大)한 핵소체(核小體) 및 포상핵(胞狀核)등의 세포학적(細胞學的) 특징을 가지며 이것은 거대(巨大) beta 도서(島嶼)가 보통 크기의 Langerhans 도서(島嶼)에 비하여 더 활발하게 insulin을 분비(分泌)한다는 것을 시사(示唆)하는 것이다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.56-68
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• 1981

A maize line was selected in 1979 among 1000 Korean local maize lines collected in 1977. The selected maize line was characterized by having three to four tillers and eight to 10 ears on each individual plant. The line was assumed to have a great potential as a silage crop. The investigation was conducted as one of the serial studies on the Korean maize collected lines to provide basic information on the genetic variabilities of the multi-eared and tillered (MET) line and on other agronomic characters, prior to use the line as material for future breeding works for silage crop. The MET line and Suwon #19, single cross hybrid, as check variety were planted on May 1, 15 and 30, in three different levels of plant populations. The results obtained were summarized as follows: 1. The genetic variabilities of multi-ear and tillering habits were greater than environmental variabilities. 2. Total dry leaf weight of individual plant of MET line was also significantly higher than that of Suwon #19. 3. The mean number of tillers and ears bearing on the individual plant of MET line varied greatly with plant densities. The number of tillers and ears was on the average 2.9 and 7.0, respectively, when planted in 60cm. by 60cm. 4. The total dry matter and dried stem weight of the individual plant on MET line were comparable to those of Suwon #19. 5. The kernel weight from the individual plant of MET line was 5 to 40% less than that of Suwon #19, depending upon the plant densities. 6. The Kernel to stover ratio was higher for Suwon #19 than for the MET line. (41% to 35%). 7. The MET line had shown first tiller two weeks after planted on May 1. The second and third tillers appeared three to five days after the appearance of the first tiller. 8. The MET line was very specific in tillering habits. All the tillers were borne on the first few nodes of main stem below the soil surface. 9. The tillering habits of MET line were vigorous in the early part of the growing season, but less vigorous in the later part of the growing season. The number of efficient tillers bearing useable ears, was around two to three, when planted in 60cm. by 60cm. 10. The difference of plant height between main stem and first few tillers was around 10cm. 11. The ear size of MET line was around one-third of the major corn belt hybrids. The shape of ear of MET line was conical, with different diameter. 12. The kernel of the MET line was flinty with small soft starch patches on the endosperm part. 13. The 100 kernel weight was around 15gr., which is about one half of the major high yielding hybrids. 14. The ear height of MET line was comparatively higher than that of Suwon #19. 15. Significantly high and positive phenotypic correlation coefficients were obtained among major plant characters. 16. The growth rate of MET line was slower than that of Suwon #19. 17. MET line and Suwon #19 were both heavily infected with black streaked mosaic virus.

• Journal of Astronomy and Space Sciences
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• v.22 no.3
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• pp.329-352
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• 2005

Long term observations of full-disk Lyman-o irradiance have been made by the instruments on various satellites. In addition, several sounding rockets dating back to the 1950s and up through the present have measured the $Lyman-{\alpha}$ irradiance. Previous full disk $Lyman-{\alpha}$ images of the sun have been very interesting and useful scientifically, but have been only five-minute 'snapshots' obtained on sounding rocket flights. All of these observations to date have been snapshots, with no time resolution to observe changes in the chromospheric structure as a result of the evolving magnetic field, and its effect on the Lyman-o intensity. The $Lyman-{\alpha}$ Imaging Solar Telescope(LIST) can provide a unique opportunity for the study of the sun in the $Lyman-{\alpha}$ region with the high time and spatial resolution for the first time. Up to the 2nd year development, the preliminary design of the optics, mechanical structure and electronics system has been completed. Also the mechanical structure analysis, thermal analysis were performed and the material for the structure was chosen as a result of these analyses. And the test plan and the verification matrix were decided. The operation systems, technical and scientific operation, were studied and finally decided. Those are the technical operation, mechanical working modes for the observation and safety, the scientific operation and the process of the acquired data. The basic techniques acquired through the development of satellite based solar telescope are essential for the construction of space environment forecast system in the future. The techniques which we developed through this study, like mechanical, optical and data processing techniques, could be applied extensively not only to the process of the future production of flight models of this kind, but also to the related industries. Also, we can utilize the scientific achievements which are obtained throughout the project And these can be utilized to build a high resolution photometric detectors for military and commercial purposes. It is also believed that we will be able to apply several acquired techniques for the development of the Korean satellite projects in the future.

• Korean Journal of Weed Science
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• v.30 no.4
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• pp.330-339
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• 2010

In order to suggest correct direction of researches on Miscanthus spp. which are promising bioenergy crop, authors had reviewed and summarized various literature about botanical taxonomy, morphology and present condition of breeding, cultivation and utilization of miscanthus. Among the genus of Miscanthus which are known 17 species, the most important species are M. sinensis and M. sacchariflorus which origin are East Asia including Korea, and M. x giganteus which is inter-specific hybrid of tetraploid M. sacchariflorus and diploid M. sinensis. Miscanthus is superior to other energy crops in resistance to poor environments including cold, saline and damp soil, nitrogen utilization efficiency, budget of input energy and carbon which are required for producing biomass and output which are stored in biomass. The major species for production of energy and industrial products including construction material in Europe, USA and Canada is M. x giganteus which was introduced from Japan in 1930s. In present, many breeding programs are conducted to supplement demerits of present varieties and to develop "Miscanes" which is hybrid of miscanthus and sugar cane. In Korea, the researches on breeding and cultivation of miscanthus were initiated in 2007 by collecting germplasms, and developed "Goedae-Uksae 1" which is high biomass yield and "mass propagation method of miscanthus" which can improve propagation efficiency in 2009. In order to develop "Korean miscanthus industry" in future, the superior varieties available not only domestic but also foreign market should be developed by new breeding method including molecular markers. Researches on production process of cellulosic bio-ethanol including pre-treatment and saccharification of miscanthus biomass also should be strengthen.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.101-108
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• 2012

This study was conducted to confirm the mass production of male pupae and sex-limited larval marking variety as a host for synnemata production of Isaria tenupes in RDA(Rural Development Administration). Silkworm pupation, infection rate and synnemate formation of I.tenuipes were examined. Among the silkworm varieties tested, male Hansaengjam showed the highest pupation rate at 98.7%. I. tenuipes infection rate of larvae of newly-exuviated 5th instar silkworm was 83.7 ~ 90.4% in the spring rearing season and 91.7 ~ 96.6% in the autumn rearing season. Synnemata production of I. tenuipes was execellent in female Yangwonjam with an incidence rate of 99.5% followed by male Yangwonjam(99.5%) and Baegokjam(99.4%) in the spring and autumn rearing season. Synnemata living weight ranged from 0.93 ~ 1.25 g in the spring rearing season. The female Hansaengjam had the heaviest synnemata weight(1.25 g). Synnemata dry weight ranged from 0.27 ~ 0.35 g in the spring rearing season. The female Yangwonjam had the heaviest synnemata weight(0.35 g).