• KOREAN JOURNAL OF CROP SCIENCE
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• v.11
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• pp.105-117
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• 1972

This experiment has been made to study the relationship between several characters affecting the field lodging and to establish some useful standards for selection of lodging resistant varieties and to classify the degree of lodging resistance in wheat and barley varieties of different sources. The experiment was carried at the Crop Experiment Station, Suwon in 1968. The results obtained are summarized as followings. a. The lodging index modified with bending moment of culm at breaking seemed to be the most useful character in checking the lodging resistance. Highly significant positive correlation (Barley; r=0.40-0.67, Wheat; r=0.46-0.68) was obtained between the lodging index and actual field lodging. b. Between two essential components expressing bending stiffness of the culm, the bending moment at breaking and secondary moment of inertia, a highly significant positive correlation (Barley; r=0.59, wheat; r=0.46-0.53) was observed. c. The bending stiffness of culm got stronger as the dry weight per unit culm, which express the quantity of accumulated dry matters in culm, increased. The correlation coefficient between those two factors was 0.35 to 0.40 in barley and 0.33 to 0.76 in wheat respectively. d. In both wheat and barley, highly significant negative correlation between lodging index and the other factors such as dry weight per unit culm (Barley; r=-0. 51 to -0.70, Wheat; r=-0.65 to -0.83) and bending moment of culm at breaking (Barley; r=-0.29 to -0.69, Wheat: r=-0.54 to -0.89) were observed. Particulary, weight of culm at breaking, secondary moment of inertia and section modulus showed significant negative correlation with lodging index in wheat. e. Outside diameter of culm expressed more intimate relationship with physical characteristics of culm than inside diameter and also showed highly significant correlation with weight of culm at breaking (Barley; r=0.42-0.56, Wheat; r=0.39-0.44) and with bending moment of culm at breaking (Barley; r=0.40-0.41, Wheat; r=0.38-0.49) and with secondary moment of inertia (Barley; r=0.56-0.57, Wheat; r=0.28-0.98) and with section modulus (Wheat; r=0.22-0.96). Between the thickness of culm and physical characteristics of culm also showed the positive correlation. f. There was positive correlation between the culm length and actual field lodging in several groups of variety among the varieties tested. But the culm length seemed to undesirable as a selection measure for the selection of the lodging resistant variety considering the stiffness of culm. g. In classification of lodging resistance for the varieties tested, many Korean barley varieties expressed excellent lodging resistant than wheat, but most of the wheat and barley varieties from Japan considered quite resistant to lodging. h. In selection of lodging resistant varieties, lodging index lower than 1.67 in barley and 1. 76 in wheat considered highly resistant to actual field lodging.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.429-436
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• 2005

As Sclerotinia sclerotiorum causing cucumber sclerotinia rot was the fastest in the mycelial growth at $25^{\circ}C$, its pathogenicity was strong at the same temperature among several temperatures. All the isolates of Sclerotinia sclerotiorum showed a strong pathogenicity against cucumber fruits, which was confirmed by a disk assay and a wound assay. A wound assay was superior to a disk assay to develop the assay system for assessing the fungicidal activity of several fungicides against Sclerotinia sclerotiorum. In a disk assay, it was very difficult to assess the fungicidal activity, because the pathogenicity of isolates used in the experiment was very strong. At 500 and $3.0{\mu}g/mL$, the activity of dichloflouanid and the mixture of carbendazim and diethofencarb against cucumber sclerotinia rot was 14.3 and 42.3%, respectively, by using a disk assay. However, at same concentration two fungicides showed the high controlling activity as 100 and 92.5%, through a wound assay in a laboratory. Also, the activity of two fungicides was good against cucumber sclerotinia rot in the greenhouse where cucumber plants were cultivated in the field, showing the control value as 91.1 and 82.9% at 100 and $825{\mu}g/mL$, respectively. All the isolates of Sclerotinia sclerotiorum from cucumber fruits sampled in the polyvinyl house were subjected to monitoring for the resistance to 7 fungicides. The $EC_{50}$ value of 7 fungicides was as follows: fenhexamid; $0.13{\mu}g/mL$, procymidon and iprodione; 0.18 and $0.24{\mu}g/mL$, carbendazim and the mixture of carbendazim and diethofencarb; 0.13과 $0.05{\mu}g/mL$, iminoctadine and dichlofluanid; 1.94 and $8.95{\mu}g/mL$. Ultimately it was not found that resistant isolates of Sclerotinia sclerotiorum were appeared in the field.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.6
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• pp.405-410
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• 2000

This experiment was conducted to investigate to the degree of damage by stink bugs at the soybean fields of Kyong-buk Agricultural Research and Extension Services from 1997 to 1998. Thirty different soybean varieties including Hwangkeumkong were used. Stink bugs collected in the soybean fields were Riptortus clavatus, Nazara antennata, Piezodorus hybneri, Dolycoris baccarum, and Halyomorpha halys, etc. The damage rates by stink bug were 5.0-12.5% in determinate types and 36.1-50.0% in indeterminate ones, which indicated that stink bugs preferred indeterminate types to determinate ones. The control values to sting bugs by fenitrothion, triaazophos, and carbaryl, were 83.4%, 69.5%, and 87.0%, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.732-737
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• 2016

Using the pyrolyzed carbon black (PCB) from waste tires, the performance of 13 mm dense-graded hot mix asphalt was evaluated. The Marshall mix design was carried out and the measured optimal asphalt content was 5.8%. The impact resonant test was conducted to obtain the elastic modulus and damping ratio of the hot mix asphalt. The elastic modulus of HMA increased with increasing amount of PCB. On the other hand, there was no significant change in the damping ratio. The Marshall mix design, indirect tensile test, permanent deformation test, and program analysis were carried out. The strength ratio of the PCB modified asphalt mixtures was within 10%. More 10% of PCB was not good for the permanent deformation of hot mix asphalt. From the pavement design program, the use of 5% PCB in hot mix asphalt showed a decrease in the top-down crack, bottom-up crack, and permanent deformation. Judging from the limited test and analysis, the use of 5% PCB is good for enhancing the pavement performance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.86-91
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• 1989

Since most chemicals effect to the non-target organisms, present study was conducted to determine the effects of some herbicides to soybean nodule bacteria(Rhizobium japonicum) in vitro. Selective upland herbicides Alachlor, Linuron, Simazine and nonselective Paraquat were medicated to the YEMA media and survival rate of the bacteria in the medium was measured a week after incubation. Survival of soybean nodule bacteria in the media medicated with recommended concentration 400 ppm of Alachlor and Linuron were decreased significantly by 27.4 ％ and 57.8 ％, respectively. While little effect was observed in Simazine, a marked reduction of survival was observed in 200 ppm of Paraquat. Effects of Alachlor was different with isolates of the nodule bacteria. Isolate I -122 was relatively resistant and I -145 was more sensitive. than other isolates tested. Intermediate K-5 was the most resistant at the recommended dose and the survival dose was drastically reduced with increment of concentration. Nodule formation of the soybean plants was different with the varieties and isolates. The most nodulation was observed in the resistant isolates I -122 and K-S, for which the nodulation might be related with the resistance to the environmental stress factors.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.165-165
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• 2007

투명전도박막은 ITO, $SnO_2$, ZnO, 등이 있으나 $SnO_2$는 자외선 영역까지 투과시키는 우수한 광학적 특성을 나타내지만, 상당히 큰 전기저항으로 인해 현재는 현재 ITO가 널리 이용되고 있다. ITO(Indium Tin Oxide)박막은 자외선 영역에서 반사율이 높으며 가시광선영역에서는 80%이상의 뛰어난 투과율을 가지고 있다. 또한 낮은 전기저항과 넓은 광학적 밴드갭 때문에 가장 유용한 투과전도성 재료 중에 하나이다. 이러한 특성 때문에 여러 가지 문자 표시소자의 투명전극, 태양전지의 창재료, 정전차폐를 위한 반도체 포장재료, 열반사막, 면발열체, 광전변환 소자에 응용되고 있다. 일반적으로 박막의 제작에는 저항가열법과 전자선가열법, 스퍼터링법의 물리적 증착과 화학적 증착으로 나뉜다. 본 논문에서는 증착온도를 달리 하여 RF-sputtering에 의해 ITO박막을 증착한 후 온도증가에 따른 박막의 특성을 연구하였으며 또한 광역평탄화를 위한 CMP공정을 적용하여 증착온도가 연마에 미치는 영향을 연구하였다. 본 실험에서 사용된 ITO박막은 $2{\times}2Cm$의 Corning glass위에 증착되었으며 타겟은 $In_2O_3$와 $SnO_2$가 9:1로 혼합된 Purity 99.99%이상의 직경 2 inch인 ITO타겟을 사용하였다. 박막 증착시 기판온도는 상온에M $200^{\circ}C$까지 변화시켰으며 RF power는 100W로 일정하게 하였으며 증착압력은 $8{\times}10^{-2}$Torr이였다. CMP공정조건은 헤드속도 60rpm, 플레이튼 속도 60rpm, 슬러리 주입 유량 60mml/min, 압력 $300g/cm^2$이였다. 전기적 특성은 four point probe를 이용하여 측정하였으며 광학적 특성은 UV-Visible Spectrometer를 이용하여 200~900nm의 파장범위에서 광투과도를 측정하였다.

• International Journal of Highway Engineering
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• v.8 no.1 s.27
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• pp.1-13
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• 2006

This paper is one of the studies for developing new methodologies for improving performance of hot-mix recycled asphalt mixtures. The objective of this study is to evaluate rut-resistance characteristics of recycled asphalt mixture which was prepared by newly developed mixing method. The new mixing method provided more sufficient rejuvenation of old binder of reclaimed asphalt pavement (RAP), making homogeneous binder viscosity level in a recycled mixture. Two aggregates (gneiss and granite), two RAP contents (15% and 30%) and two contents (none and 6%) of polymer modifier (LDPE) were used. Recycled mixture was prepared with two methods; method A and method F. To examine difference of binder oxidation level by type of material within a recycled mixture, Gel-permeation chromatography(GPC) analysis was performed on the binders mixed with coarse aggregates and matrix separately. Laboratory tests were performed for evaluation of rut resistance characteristics of each recycled mixture and these includes wheel tracking (WT) test and Kim test. Rut depth and dynamic stability were obtained from WT test and deformation strength $(S_D)$ was obtained from Kim test. The results of regression analysis was shown that correlation $(R^2)$ of F mixing mixtures was higher than one of A mixing mixtures. Therefore, F mixing mixtures showed more consistent rut resistance than h mixing mixtures.

• Research in Plant Disease
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• v.24 no.4
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• pp.313-320
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• 2018

Fusarium infection rate of the paddy rice grain after harvest seemed to be influenced by the average temperature from late July (before heading) to the end of September (during ripening). In case of 2010 and 2013 in which average temperature of the same period was similar, Fusarium infection was related to cumulative precipitation, cumulative precipitation days, and precipitation durations over two days. The distribution ratio of Fusarium species complex isolated from paddy rice grains after harvest was 57% in 2010 and 45% in 2013 for Fusarium graminearum species complex (FGSC), 35% and 50% for Fusarium incarnatum-equiseti species complex, and 8% and 5% for Fusarium fujikuroi species complex (FFSC). The distribution ratios of FGSC and FFSC were higher in 2010 than 2013. Among the total 26 promoted rice varieties, the 'Mihyang' showed resistant response against the natural infection with Fusarium species belonging to FGSC and the varieties of 'Nampyeong', 'Hi-ami'and 'Younghojinmi' showed resistant response against the natural infection with overall Fusarium pathogens. Majority of the promoted rice varieties could not be classified for resistance or susceptibility. These results are valuable as basic data to determine the resistance and susceptibility of rice variety against Fusarium spp. infection in the field.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.53-61
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• 2024

The susceptibility of Aphis gossypii populations collected from three fields (WJ, CC, and GS) was evaluated to three insecticides (afidopyropen, chlorfenapyr and cyantraniliprole) and three binary mixtures. Three field populations showed resistance ratios of over 100 to all insecticides. The Combination Index (CI), %M_(synergism), Co-Toxicity Coefficient (CTC), Wadley Ratio (WR), Synergism Ratio (SR) and Abbott Ratio (AR) were used to evaluate combined effect of the insecticides. Afidopyropen + chlorfenapyr (CI ≤ 0.16; %M_(synergism) ≥ 94; CTC ≥ 764.5; WR ≥ 6.4; SR ≥ 6.9 and AR ≥ 1.1) showed a synergism in all filed populations. WJ and CC populations showed a synergism in all binary mixtures of insecticides, but GS population showed an antagonism for chlorfenapyr + cyantraniliprole (CI, 1.63; %M_(synergism), 30; CTC, 64.0; WR, 0.6 and AR, 0.54) and afidopyropen + cyantraniliprole (CI, 6.7; %M_(synergism), 1; CTC, 19.8; WR, 0.2 and AR ≤ 0.55). All mixtures (afidopyropen + chlorfenapyr, chlorfenapyr + cyantraniliprole and afidopyropen + cyantraniliprole) showed a control value of over 99% after 21 days of treatment in the field. This study highlights that binary mixtures of three insecticides serve as an effective control strategy for A. gossypii.

• Research in Plant Disease
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• v.17 no.3
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• pp.288-294
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• 2011

Rice bakanae disease, caused by the fungus Fusarium fujikuroi, is one of the most important rice diseases and distributed widely in Asia. Resistance screening system in rice field had been established. However, the evaluation results of the system vary according to the environmental conditions when the test is conducted. To develop precise and rapid evaluation method of disease resistance of rice to bakanae disease, in vitro screening system was attempted in this study. The six cultivars namely, 'Nampyeongbyeo', 'Junambyeo', 'Chucheongbyeo', 'Samcheonbyeo', 'Odaebyeo' and 'Hwasinbyeo' were tested. They were planted onto MS agar medium (10 ml) in test tube ($450\;mm{\times}{\phi}30\;mm$) and incubated at $25^{\circ}C$ and $28^{\circ}C$ in growth chamber under 12 hr light condition. Symptoms of over growth appeared a few days after seeding and then seedling were withered 2-3 weeks after over growth. The disease symptoms such as leaf dryness on top of rice were appeared in the 'Nampyeongbyeo' from 28 days at the concentration of $10^5$ spores/ml culturing at $28^{\circ}C$ and then withered completely 35 days after seeding. Whereas the other varieties withered entirely 19-23 days after seeding. Using the in vitro seedling screening method, 72 rice varieties were investigated to select resistant cultivar. Finally, two resistant cultivars ('Nampyeongbyeo' and 'Inwolbyeo') and seven moderately resistant cultivars ('Hwadongbyeo', 'Seokjeongbyeo', 'Samgwangbyeo', 'Sampyeongbyeo', 'Nonghobyeo', 'Heukjinjubyeo' and, 'Joanbyeo') were selected. If in vitro seedling screening method was used for evaluation of bakanae disease resistance, it would be completed within 35 days after sowing of rice seed.