• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.3
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• pp.201-208
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• 2002

This study was carried out to select the promising barley cultivar for whole crop silage in paddy Held of Suwon, Iksan and Milyang from 1998 to 2001. The heading stage of barley were April 30∼May 4, April 24∼May 3 and April 17∼29 at Suwon, Iksan and Milyang, respectively. In yellow ripe stage, fresh of barley were 24.07∼29.88, 23.18∼32.07 and 17.16∼28.11 MT per ha at Suwon, Iksan and Milyang. and dry matter yield of barley were 5.78∼9.98, 6.66∼12.73 and 7.23∼11.57 MT per ha at Suwon, Iksan and Milyang, respectively. Also, total digestible nutrient(TDN) yield was 5.67∼6.57 MT per ha at Suwon and it was best before yellow ripe stage for harvest in cropping system. The promising barley cultivars for whole crop silage in paddy field were Albori at Suwon, and Milyang 92, Saessalbori, Keunalbori, Naehanssalbori at Iksan, and Keunalbori, Albori, Naehanssalbori, Saegangbori at Milyang, respectively.

• Journal of Korean Society of Transportation
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• v.30 no.6
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• pp.3-12
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• 2012

Additive willingness-to-pay (WTP) for leisure-travel time saving focused on the Iksan-Pohang Expressway and the Donghae Expressway was surveyed during the summer months to estimate the value of travel-time savings (VTTS) for non-business leisure trips. Travelers traveling between 2 and 3 hours on Iksan-Pohang Expressway had WTP of 723 won per 10 minutes of leisure-travel time savings and those traveling between 3 and 4 hours on Donghae Expressway had WTP of 854 won per the same. Based on this survey, we learned that WTP in leisure travel time savings increased with the total travel time. 300 effective samples for each expressway were collected, and estimation was separately conducted on the basis of Cox test.

• Journal for History of Mathematics
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• v.19 no.2
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• pp.1-24
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• 2006

We study the theory of finite series in Chosun Dynasty Mathematics. We divide it into two parts by the publication of Lee Sang Hyuk(李尙爀, 1810-?)'s Ik San(翼算, 1868) and then investigate their history. The first part is examined by Gyung Sun Jing(慶善徵, 1616-?)'s Muk Sa Jib San Bub(默思集算法), Choi Suk Jung(崔錫鼎)'s Gu Su Ryak(九數略), Hong Jung Ha(洪正夏)'s Gu Il Jib(九一集), Cho Tae Gu(趙泰耉)'s Ju Su Gwan Gyun(籌書管見), Hwang Yun Suk(黃胤錫)'s San Hak Ib Mun(算學入門), Bae Sang Sul(裵相設)'s Su Gye Soe Rok and Nam Byung Gil(南秉吉), 1820-1869)'s San Hak Jung Ei(算學正義, 1867), and then conclude that the theory of finite series in the period is rather stable. Lee Sang Hyuk obtained the most creative results on the theory in his Ik San if not in whole mathematics in Chosun Dynasty. He introduced a new problem of truncated series(截積). By a new method, called the partition method(分積法), he completely solved the problem and further obtained the complete structure of finite series.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.220-226
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• 1998

The effects of metalaxyl(granule), carbofuran(granule) and simazine(water soluble powder) on the soil microflora were conducted at field soil between Iksan and Chonju province. Pesticides were divided into 0.5, 1, 1.5 and 2.0 times of normal of field, respectively. The number of fluorescent Pseudomonas was ranged from $10^3$ to $10^6/g$ in both field soil treated with cabofuran. Pseudomonas concentration of Chonju field soil slowly increased and approached the maximum level at 56 day after treatment(DAT). It showed the higher at 14DAT than other DAT in Iksan field soil treated with metalaxyl or simazine, whereas it increased again at 112 DAT in metalaxyl treatment. Cabofuran treatment of both field soil showed maximum Pseudomonas number at 28 DAT compared to that of other treatments. In Chonju field soil, those Pseudomonads of metalaxyl and simazine treatment increased the highest level at 7 DAT. Simazine treatment decreased it's number from the beginning of experiment. In both soil, metalaxyl treatment decrease the general fungi number at 7 DAT, but increase at 14 and 56 DAT in Iksan field soil. However it increased at 56 DAT in Chonju field soil. Cabofuran treatment of Iksan field soil tended to decrease general fungi number at 28 DAT, but was ranged from 1.0 to $8.6{\times}104/g$ for the rest of experimental period. It started to increase at 56 DAT simazine treatment of Iksan. General bacterial concentration both soil treated with cabofuran was belong to $26.6{\sim}29.6{\times}106$. It was the highest at 56 DAT, but was not significantly different. General actinomyces number was highly increased at 7 and 112 DAT compared to that of other DAT. Pseudomonas putida or P. fluorescens from both field soil was separated and identified 10 to 30 of all 104 Pseudomonas, respectively. All isolated microorganisms showed chemical resistance of 100ppm metalaxyl, cabofuran and simazine treatment.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.62-67
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• 1999

As a basic experiment to enhance the symbiotic utility of atmospheric nitrogen on soybean, host affinities and serological distribution of Bradyrhizobium japonicum indigenous to five Korean upland soils were measured. Based on nodulation, the symbiotic affinities between indigenous B, japonicum and eight soybean cultivars were remarkably different among soil inocula. On the whole, the averaged affinities of B. japonicum populations to soybeans were favorable in order of Goseong > Milyang > Suweon soils, but those in Iksan and Namjeju soils were not, especially for Danweonkong, Jangkyeongkong, and Eunhakong soybean cultivars. Regression analyses between nodules mass and shoot dry weight of soybean yielded model with $R^2=0.51$ for Goseong, $R^2=0.45$ for Milyang, $R^2=0.38$ for Iksan, $R^2=0.28$ for Namjeju, and $R^2=0.24$ for Suweon soils. B. japonicum from sampled soils were serologically fell into more than seven serogroups such as YCK 117(34.1%), YCK 141(6.5%), YCK 321(6.5%), YCK 445(4.7%), YCK 338(2.9%), YCK 150(1.2%), YCK 258(0.6%). The dominant serogroup YCK 117 was distributed 51.9 for Namjeju, 45.8 for Goseong, 41.7 for Iksan. 34.2 for Sueveon, and 11.1% for Milyang soils.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.34-39
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• 2006

The land use pattern, water quality and vegetation were investigated in the six tributaries, including Hanggeumcheon and Satancheon of the Namhan hydrosphere, Iksancheon, Jeonjucheon and Gosancheon of the Mankyung hydrosphere as well as Jongeupcheon of the Dongjin hydrosphere. Forest and farmland area were extensive in Hanggeumcheon, Satancheon and Gosancheon. Farmland and livestock area were wide in Iksancheon. Jeonjucheon were occupied with broad urban. Industrial and urban area were extensive in Jongeupcheon. The loading amounts of biochemical oxygen demand (BOD), total nitrogen (T-N), total phosphorus (T-P) of Iksancheon and chemical oxygen demand (COD) of Jeonjucheon were determined to be very high, respectively. The quality of water in Hanggeumcheon, Satancheon and Gosancheon were determined to be good quality. The species diversity was lower in the down stream than in the upper stream except for the Gosancheon. Life form of plane were mostly perennial plane in the upper stream and annual plants in the down stream of rivers. It was estimated that there is high level of disturbance in the down stream of rivers. The quality of water was significantly correlated with farmland and forest area. In conclusion, human impact, such as farmland and housing lot exerted an influence on the disturbance of down stream and the water quality of rivers.

• Journal of Life Science
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• v.14 no.5
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• pp.821-828
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• 2004

The increasing apparent photosynthetic rate per leaf area may improve seed yield in soybean. Leaf area, length and width are related to the photosynthetic capability of the plant. In this study, two populations derived from the cross of Keunolkong, Shinpaldalkong and Iksanl0 were evaluated with simple sequence repeat (SSR) markers to identify length, width and length/width ratio of leaf. Leaf length/width ratio were significantly negative correlation with leaf width in K/S and K/I populations. In the K/S population, two minor QTLs for leaf length (LL) were found on LG Dlb+W and 1. Two QTLs on LG J and L were related to LL in K/I population. Two and three minor QTLs were identified in leaf width with total phenotypic variation of 13% and 18.04 in K/S and K/I populations, respectively. The leaf length/width ratio, two QTLs on LG I and L, and three QTLs on LG Cl, E and L were related to K/S and K/I populations, respectively. Thus it is assumed that the leaf traits are very much dependent on the genotype used and different breeding approach should be considered for the selection of favorite leaf traits in soybean breeding programs.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.331-338
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• 2017

In the present study, we investigated the effects of two herbicide-resistant genetically modified rice (GM rice) varieties, Milyang 204 and Iksan 483, recently developed in Korea on non-target insects and a spider. No difference in host preferences of the English grain aphid Sitobion avenae and the brown planthopper Nilaparvata lugens were observed between GM rice and non-GM rice. Wolf spider Pirata subpiraticus, feeding on N. lugens reared on GM rice or non-GM rice, revealed no significant difference in body weight. P. subpiraticus, fed with N. lugens reared on Milyang 204, showed survival rates similar to that in P. subpiraticus fed with N. lugens reared on non-GM rice. However, P. subpiraticus feeding on N. lugens reared on Iksan 483 demonstrated significantly lower survival rates than that in P. subpiraticus feeding on N. lugens reared on Milyang 204 or non-GM rice. In addition, when larvae of the western honeybee Apis mellifera were supplied with Iksan 483 pollen, a significantly longer pupal period occurred, as compared with that of A. mellifera supplied with pollen of Milyang 204 or non-GM rice. As GM rice has negative effects on P. subpiraticus, which is an important predator in agricultural ecosystems, and on A. mellifera, which plays important roles in pollination and honey production, additional studies on risk assessment of GM rice should be conducted before releasing newly developed herbicide-resistant GM rice to the agricultural environment.

• 한국문화재보존과학회:학술대회논문집
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• 2003.09a
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• pp.28-37
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• 2003

• Geotechnical Engineering
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• v.23 no.4
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• pp.33-38
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• 2007