• Korean Journal of Environmental Agriculture
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• v.23 no.1
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• pp.7-14
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• 2004

This study was conducted to investigate the effect on agricultural environment and crop productivity by different amount of applied fertilizer in consideration of irrigation water quality. N, P and K contents of irrigation water used in this experiment were 6.16, 0.26 and 9.37 mg/L, respectively. N, P and K Concentrations of runoff water were lower than those of inflow water during rice cultivation. N, P and K Concentrations of ponded and percolated water were changed according to the amount and time of applied fertilization. During rice cultivation in paddy soil, nitrogen balance was closed to 0 in SFT 50% (50% level of soil testing fertilization), 0.14 kg/ha, but it was 95.3 kg/ha in CF (conventional fertilization) treatment In SW 50% and STF (soil testing fertilization) treatment yield of perfect rice was not greatly different as compared with CF treatment due to the superiority of ripening rate, 1,000 grains weight and milling characteristics. Mechanical paratability of rice was excellent in NF (non fertilization) treatment, STF 50% treatment showed higher in nutrient availability and fertilizers use efficiency than other treatments.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.244-249
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• 1988

Some experiments were conducted to utilize the raphanus test as a bioassay method for plant growth regulaters and hormonal herbicides. Among seven radish cultivars, the response of Jangbaegminong was the most sensitive and quantitative to ${\alpha}$-NAA and its coefficient of variation value was the lowest. The optimum application time of test compounds was estimated seven to nine days after seeding. After ${\alpha}$-NAA treatment the curvature angle of radish cotyledonary petiols was sharply increased to the maximum value at 24 hours after and was changed by light and temperature conditions. The curvature response was observed by application of ${\alpha}$-NAA, phenoxy and indole compounds but often plant growth regulators, $GA_3$ benzyladenine, ABA and homobrassinolide was not detected by this method. So this bioassay was useful to evaluate the activity of a compound as an auxin or a hormonal herbicide.

• Journal of Korean Elementary Science Education
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• v.41 no.2
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• pp.325-337
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• 2022

This study aims to determine the implications of the efficient and effective implementation of science core competency (ScC) education by examining the state of science core competencies derived from the 2015 revised elementary school science curriculum and analyzing teachers' and students' perceptions. To this end, this paper investigated the reality of reflecting the science core competencies of science textbooks in a group of third and fourth graders from seven elementary schools who passed the test. In addition, in-depth interviews were conducted with four elementary school teachers who participated in qualification textbook selection, and 156 elementary school students were surveyed to determine their perceptions of science core competencies. Findings showed that, first, 1,586 science core competencies were reflected throughout the textbooks, with an average of 227 per textbook and biology being the most salient area. Second, teachers did not understand the difference between previous inquiry activities in textbooks and ScC education. Third, no statistically significant differences were observed in the perceptions of male and female students on science core competencies, the highest average of perceptions being those of scientific thinking ability. From these results, this study concluded that for ScC education to be realized as a curriculum, textbooks must be organized according to the purpose of core competency education, implementing practical changes, and efforts must be directed toward changing the perceptions of individuals who deliver education.

• Journal of the Korean Data and Information Science Society
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• v.21 no.3
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• pp.471-480
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• 2010

Cluster analysis is one of the useful methods to find out number of groups and member’s belongings. With the rapid development of computer application in statistics, variety of new methods in clustering analysis were studied such as EM algorism and Self organization maps. The goals of cluster analysis is finding the number of groupings that are meaningful to me. If data are analyzed perfectly with cluster analysis, we can get the same results from discernment analysis.

• Korean Journal of Agricultural Science
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• v.6 no.1
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• pp.27-32
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• 1979

Seed samples of sesame (Sesamum indicum L.) from Chung-nam Provincial Office of Rural Development were infected by 12 fungi. Alternaria sesamicola, A. tenuis and Corynespora cassicola were the predominant fungi. Except C. cassicola, all fungi were almost completly reduced and wipid out the infections by pretreatment with chlorine. Plating of seed components also indicate that C. cassicola was well-established infections. In infection experiment C. cassicola produced severe leaf and stem spots and blights on sesame plants and showed severe seed and seedling rot.

• Proceedings of the Korean Society of Computer Information Conference
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• 2019.01a
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• pp.305-306
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• 2019

2019학년도 초등학교 5-6학년군에 2015 개정 교육과정이 전면 적용된다. 본 논문에서는 2015 개정 교육과정에 따른 실과 검정 교과서 6종 소프트웨어 교육 단원의 외적 체제를 비교 분석하였다. 단원 체제 분석 결과 모든 교과서에 공통적으로 대단원명, 대단원 차례, 중단원명, 본문텍스트, 본문삽화, 용어 설명, 단원 마무리 등이 제시되어 있었다. 단원 구성 분석 결과 소프트웨어 교육 단원은 전체 교과서 분량의 18.8~25%까지 교과서별로 다양한 비율을 차지하고 있었다. 후속 연구로는 본 논문에서 다룬 교과서의 외적 체제 뿐 아니라 내적 체제 까지를 포함하여 각 교과서의 소프트웨어 교육 단원을 전체적인 틀에서 비교 분석 할 것이다.

• International Journal of Highway Engineering
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• v.10 no.4
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• pp.1-8
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• 2008

Seoul metropolitan government has introduced Bus Rapid Transit (BRT) systems in some major urban corridors on July 1st, 2004, and has reported that it was successful on the ground that bus speed has been increased in the corridors with BRT system and that it has also resulted in the increase of bus patrons. However, there comes a negative claim that BRT has increased the number of fatalities in the same corridors. This study first aims at developing safety evaluation indicators of pedestrian crossings, then compares values of those indicators from pedestrian crossings with and without BRT systems. The safety evaluation indicators of pedestrian crossing are developed as: the number (or ratio) of conflicts between pedestrians and vehicles, the number (or ratio) of vehicles violating pedestrian signals, the number (or ratio) of pedestrians remaining crossings at red signals, and the number (ratio) of pedestrians walking beyond crossing areas. When we compare values of these indicators for both pedestrian crossings with and without BRT system, it has turned out that crossings with BRT systems has more number of conflicts than the crossings without BRT systems, but it cannot be said that the ratio of conflicts will be different between two crossing types. It means that the number of conflict will increase as the number of pedestrians and vehicles in the crossings. When we note that BRT system intrinsically attract more number of pedestrians who get-in or get-off bus stops, we cannot said that BRT system will be safer for pedestrians.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.3
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• pp.187-194
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• 2010

The soybean stay green mutant genotype (SSG) derived from the nuclear gene, d1d2, and cytoplasmic gene, cytG, inhibit the breakdown of chloroplast in the leaves, pod walls, seed coats, and embryos during maturity. Soybean seed with black seed coat and green cotyledon (SBG) are preferred than black seed coat with yellow cotyledon (SBY) especially for cooking with rice and as source of traditional food in Korea. The researchers evaluated the seed's chlorophyll content of SSG and introduced SSG to the SBG variety breeding program. The seed chlorophyll content of SSG with d1d2 was $39.93{\sim}60.80\;{\mu}g/g$ and SSG with cytG $38.08{\sim}39.89\;{\mu}g/g$. The Korean SBG variety which was derived from SSG with cytG, contains $16.35{\sim}37.73\;{\mu}g/g$. The composition of seed chlorophyll differs according to the genetic background of SSG genotype. Inheritance study showed that cotyledon color was segregated 15:1 (yellow:green) at $F_2$ seed indicating two recessive genes control green cotyledon as revealed by previous study. Only less than 3% soybean lines showed black seed coat with green cotyledon among crosses SBY and SSG (d1d2). Results showed that SSG with d1d2 can be used as a good source for SBG with high chlorophyll content in the seed cotyledon, but due to the complex genetic behavior, breeding resource of SBG with d1d2 should be prepared to improve the breeding efficiency for development SBG variety.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.345-350
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• 1991

Rough rice samples of Chucheongbyeo, Bongkwangbyeo and Hwaseongbyeo were collected by the National Agricultural Products Inspection Office. Drying methods of rough rice were sun drying and forced ventilation drying by an oven dryer and temperature of the oven dryer was set to 43, 60, 70, or 8$0^{\circ}C$. Moisture content of samples was reduced from ca. 20% to 15% at the end of drying, and additionally to 12.5 % for the drying at 8$0^{\circ}C$. Characteristics related to rice grain quality, milling recovery, ratio of broken and cracked rices, percentage of germination, and sensory scores of the cooked rices were evaluated. Yielding percentage of brown rice and polished rice remarkably decreased by drying at 8$0^{\circ}C$. Percentages of cracked rice and broken rice were within the criterion of the second grade government brown rice (20%) only in the sun dried and the rices dried at 43$^{\circ}C$, on the basis of damaged rice, opaque kernel rice and colored rice. Broken rice percentage of the polished rice was within the criterion for the standard of government rice (5%) in the sun dried and the rices dried at 43$^{\circ}C$. Germination percentage of rough rice was higher than 80% in sun drying and drying at 43$^{\circ}C$, but remarkably decreased by drying rice at 6$0^{\circ}C$ and over. Sensory palatability of the cooked rice decreased with increase in drying temperature. The present governmental method of judging rough rice on the basis of moisture content and appearance of the rough rice appears to be improved to include the ratio of broken and cracked rices.

• The Korean Journal of Food And Nutrition
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• v.17 no.2
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• pp.229-235
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• 2004

Chemical composition, total dietary fiber(TDF), oligosaccharide, isoflavone and phytic acid contents of seven domestic and three imported soybean cultivars were determined. TDF contents were ranged from 16.83 to 21.71％(w/w) without remarkable differences among soybean cultivars. Phytic acid contents of domestic cultivars such as Geomjongkong 1 (3.02％) and Dawonkong (2.92％) were higher than imported ones such as Canadian (2.07％) and American (2.22％) soybeans for soybean sprout and US No. 1 (2.16％). The phytic acid contents of cotyledon parts were 1.5 to 2 times higher than those of hypocotyl parts. Isoflavone contents in whole seed were wide ranged from 371 to 2,398 $\mu\textrm{g}$/g among cultivars and it were existed mainly as glucoside isomers. Profiles of isoflavone aglycones were composed of 52％ genistein, 36％ daidzein and 11％ glycitein. Hwanggumkong, Dawonkong, Geomjongkong 1 and American soybean for sprout contained lower isoflavone than others. Hypocotyl parts of soybeans contained from 6120.1 to 16921.1 $\mu\textrm{g}$/g isoflavone with ratio of 48％ glycitein, 35％ daidzein and 10％ genistein. Isoflavone contents of cotyledon parts were ranged 375-2393 $\mu\textrm{g}$/g, composition of which had no glycitein, 55％ genistein and 38％ daidzein. Oligosaccharide contents were similar among cultivars. Stachyose of 3.0-3.9％, raffinose of 0.8-1.2％, sucrose of 4.5-7.8％ and fructose of 0.3-0.8％ were determined.