• Research in Plant Disease
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• v.19 no.1
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• pp.7-11
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• 2013

Forty eight isolates of Botrytis elliptica and 23 isolates of B. cinerea from several locations in Korea were tested for resistance to fungicides used in the farmer's fields. Isolation frequency of B. elliptica having $EC_{50}$ (effective concentration of 50%) value $500-1000{\mu}g/ml$ to benomyl and mancozeb appeared highly, suggesting that the two fungicides are not effective in controlling leaf blight of lily in the field. The isolates were tested for resistance to fungicides procymidone and iprodione which were most commonly used in the farmer's fields. The rates of $EC_{50}$ value $5-50{\mu}g/ml$ to procymidome and iprodione were 93.7% and 100%, respectively, and those of $0-0.1{\mu}g/ml$ to diethofencarb+carbendazim and fludioxonil were 98.0% and 93.8%, respectively. In the rain-protected cultivation, control of leaf blight of lily was the most effective when iprodine, diethofencarb+carbendazim, and fludioxonil were sprayed alternately four times during the growing season.

• Korean journal of applied entomology
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• v.22 no.1 s.54
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• pp.1-6
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• 1983

The survey on the occurrence and distribution of barley stripe disease was conducted in the farmer's field of 19 gun (county) throughout Yeongmm area in May of 1982, in order to obtain a basic information on the breeding of resistant varieties, and for control of the disease. The percent of infected culms of barley stripe disease in Gyeongnam province (Southern Yeongnam) was higher $(13.7\%)$ them in Gyeong-bug $(6.9\%)$, northern Yeongnam, and especially, Ham-an, Milyang, Eui-chang and Weol-seong were severly occurred. The cultivar of Millyang 6 was slightly infected while the cultivars Olbori and Oweolbori were severely infected by the disease. Among soil conditions, the barley plant grown in the loam, clay and clay loam texture which have more availble moisture, and that of the plant cultivated in the poorly drained soils were shown to have severe infection. The barley plant grown in the soils in local valley $(18.8\%)$ where is frequently over saturated with water showed the more infection the barley plant grown in plains $(9.5\%)$. Generally, the poorer the soil drainage the more severeinfection occurred. Among cultivation conditions, the earlier the sowing dates of the barley, the less the percent of infected culms was observed. The heavier or lighter application of N fertilizer than the optimum to barley plant seemed to cause more infection.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.72-72
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• 2017

국내 농업에서 토양의 반전, 쇄토, 배토, 가능한 복합작업기인 무동력 디스크해로우 방식의 경운과 배토 고효율 복합작업기의 수요가 증가 하고 있다. 경운작업에서 일련의 과정은 작물의 생육과 관리차원에서 큰 의미를 지니며 작물재배의 첫 단계로 중요시 다루어져야할 과정이다. 이러한 작업기의 성능 시험에서 포장시험을 통해 복합기의 신뢰도와 실제 필드에서 발생하는 문제들을 포괄적으로 해결 할 수 있는 방안이 필요하다. 토양 경작을 위한 농업기기의 작업 저항은 식물 생산에서 유용성을 평가하는 가장 중요한 지표중 하나이다. 작업 저항(수평, 수직 방향의 힘)은 트랙터의 힘에 의해 생성된 동작을 방해하므로 토양 경운 시 에너지 소비를 결정하고 설계 매개 변수 측면에서 최적의 작업 조건을 결정하는 데 중요한 영향을 미친다. 따라서 본 연구에서는 경상대학교 내 위치한 실험동에서 Soil-bin에 이송장치를 설치한 후, 이송장치에 디스크 해로우 (Multidisc Vario, Tulip Agri., Netherlands)를 부착하여 실험을 진행하였다. 디스크 해로우의 원주 평면과 수직 평면 사이의 각 a(토양 표면에 수직)와 디스크의 해로우의 원주 평면과 작업 방향 사이의 각 b의 값을 독립 변수로 두고 a, b를 변화 시키면서 발생하는 이송장치의 견인력을 측정하여 농가 및 효율적인 경운작업 시 기초자료로 활용하고자 한다.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.298-311
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• 2015

Grape is one of the important fruit crops around the world, and exposed to disease and pests, and internal or environmental stresses in the vineyards. Breeding and cultivation of new varieties of high quality-grapes resistant to diseases and pests and tolerant to stresses are the most important steps in the grape production. However, conventional breeding has laborious and time-consuming procedures in maintaining and selecting seedlings in the fields. Development of molecular breeding technology through understanding of molecular mechanism of useful traits can be used as an alternative strategy to improve the efficiency of grape breeding program by cross hybridization in grape development programs. The completion of the grape genome sequencing project provided the way to discover the novel genes and to analyze their functions. Comparative genomics, transcriptomic analysis, and the genome-wide identification and analysis of useful genes as well as development of molecular marker for valuable traits could provide novel insights into fruit quality and the responses to diseases and stresses, and can be used as important information in molecular breeding programs for grape development.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.685-688
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• 2008

Concrete is strong on the compressive property, but weak on the tensile and flexural properties. To improve these problems, the reinforcing bar is used in concrete. But porous concrete with steel fiber has a weak point when exposed to air, because porous concrete has the vast continuous void on its inside and steel fiber is easily rusted by air. For these reasons, this study investigated the void ratio, compressive strength, bending strength and bending toughness as steel fiber mixing ratio and target void ratio. From test results, actual void ratio and strength properties increased as the mixing ratio of steel fiber increase. In case the mixing ratio of steel fiber over the fixed ratio, strength is decreased. And from the toughness evaluation, compared to the porous concrete which isn't mixed with steel fiber, the deflection variation efficiency is remarkably improved. Consequently we can confirm the possibility of porous concrete with steel fiber for the secondary product and pavement material to improve strength and bending resistance efficiency.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.485-489
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• 2018

A mungbean cultivar "Munpyeong" (Vigna radiata (L.) Wilczek) was derived as a cross between "Keumseong" and "IT163157" at the Jeollanamdo Agricultural Research and Extension Services (JARES) in 2013. "Munpyeong" has an erect growth habit, heart leaflet, green hypocotyls, black and straight pods when matured, and a dull green seed surface. The stem length of "Munpyeong" was 60 cm, which was 6 cm shorter than that of the control cultivar "Owool." The pod number per plant was 25, which was 3 more than that of the control cultivar. The 1000 seed weight of "Munpyeong" was 45 g, which was 4 g lighter than that of the control cultivar "Owool." Its field resistance to mungbean mottle virus, cercospora leaf spot, and powdery mildew are similar to the control cultivar, whereas its field resistance to lodging was slightly stronger. The hard seed rate of "Munpyeong" was 3.2%, which was similar to that of the control cultivar. The sprout yield ratio was 7.54 times, which was 9% more than that of the control cultivar. The average yield of "Munpyeong" was 1.93 ton/㏊, which was 21% more than that of the control cultivar "Owool" (Cultivar registration number: 5878).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2D
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• pp.243-248
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• 2008

Moisture damage of asphalt pavements can usually occur because of the loss of adhesion and cohesion between the asphalt binder and aggregate in the asphalt mixture due to presence of water. And this is one of the causes that is effect on the main distress of asphalt pavement. The objective of this study is to find out moisture damage characteristics of asphalt pavement. Effects of this study changes of the material properties and resistance characteristics of moisture damage on the asphalt mixtures under various temperatures and repeated immersion using indirect tensile test and modify Lottman test were evaluated during this study. The asphalt mixtures were produced using straight asphalt binder, SBS modified asphalt binder and aggregates. The material properties (resilient modulus, indirect tensile strength, failure energy and $DCSE_f$) of the asphalt mixtures were generally decreased with increasing to moisture damage caused by the number of repeated immersion. The decrease ratios of material properties by repeated immersion on SBS modified asphalt mixtures were lower than those of straight asphalt mixtures at all three test temperatures. As a conclusion, current criterion for evaluation moisture damage of asphalt mixtures is difficult for using distinction standard because of the limited evaluation criterion with one time immersion and single material property. Based on this research, to evaluate long term moisture damage on asphalt mixtures, material property tests of various kinds with repeated immersion test are considered.

• Korean Journal of Environmental Agriculture
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• v.32 no.2
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• pp.117-122
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• 2013

BACKGROUND: The scab, which is caused by Venturia nashicola, gives serious damages to pear trees. 'Niitaka' accounts for 82% of areas in pear cultivation. However 'Niitaka' is a scab susceptible cultivar. So, most of Korean farmers who growing pear trees have suffered by economic losses with the scab. In this research, we evaluated the scab resistance among elite pear seedlings to clarify genetics about the scab resistance. And we analyzed photosynthetic features with these seedlings to develop suitable cultivar which is advantageous for producing quality fruits during the growth and development of plants. METHODS AND RESULTS: We measured the rates of scab incidence among seedlings in a field experiment condition and an in-vitro test. An in-vitro test has been done with field experiment-based results. We made plant materials by grafting branches of each seedlings with 'Kongbae' rootstocks. And they had been grown for one month. Then, scab conidia suspension is sprayed to seedlings and sustained for 40 days under the controlled environment. As the results, 6 seedlings displayed lower incidence rates than other seedlings and 'Niitaka'. We also measured instant photosynthetic rates of each seedlings to determine the correlation between photosynthetic rates and fruit characteristics. However, it seemed that there is no correlation between them. CONCLUSION(S): Among the seedlings, 6 seedlings displayed the higher resistance to scab than other seedlings and 'Niitaka'. This characteristics is considered to be come from the gene expression of European pear. And we found that photosynthetic rate in trees rarely does not influence the fruit characteristics. It is considered to be affected by cultivar's own characteristics.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.291-299
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• 2010

Cyhalofop-butyl and penoxsulam, known for respective acetyl CoA carboxylase (ACCase) and acetolactate synthase (ALS) inhibitor, have been widely using as a post-emergence foliar application for many years in wet-seeded rice field in Korea. Since 2009, control of Echinochloa oryzoides with cyhalofop-butyl and penoxsulam was no longer satisfactory. Greenhouse and experiment in rice field were conducted to confirm E. oryzoides resistance to ACCase and ALS inhibitors and to compare herbicide treatments for control of the resistant E. oryzoides to ACCase and ALS inhibitors. Three resistant E. oryzoides to ACCase and ALS inhibitors accessions were tested for levels of resistance to cyhalofop-butyl and penoxsulam, base on survival rate. Iksan and Kimje accessions were not any affected to the survival by treatment with recommended doses of two herbicides tested. Buan accession displayed an intermediate response of 62 and 72% survival at recommended doses of cyhalofop-butyl and penoxsulam, respectively. Survival rates to herbicides mixed with ACCase and ALS inhibitors at 3.5 leaf stage of E. oryzoides was over 80%. Benzobicyclon+fentrazamide+bensulfuron SC, benzobicyclon+mefenacet+bensulfuron SC, benzobicyclone +cafenstrole+pyrazosulfuron-ethyl GR controlled effectively by 2 leaf stage of resistant E. oryzoides to ACCase and ALS inhibitors. In the field experiment, single treatment of benzobicyclon+ fentrazamide+bensulfuron SC and benzobicyclon+mefenacet+bensulfuron SC failed to control E. oryzoides, but squential treatment of benzobicyclon+thiobencarb SE and benzobicyclon+ mefenacet+ bensulfuron SC controlled effectively it in rice infant seedling culture with machine. Our results suggest that resistant E. oryzoides to ACCase and ALS inhibitors had not developed multiple resistance to herbicides with different modes of action. In particular, cafenstrole, fentrazamide, mefenacet were effective control measures.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.58-58
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• 2011

CNT 나노기술을 응용한 IT산업용 적층간지용 ESD(정전방전, Electrostatic Dissipation)PU 발포필름의 제조 가공기술 및 상품화 개발은 전자제품 패키지에 요구되는 쿠션성과 정전방전 기능을 갖는 폴리우레탄 발포 필름의 제조기술을 확립함으로써 가능 할 수 있다. 특히 IT산업용 필름제품이 개발되면 ESD 성능을 발휘하게 됨으로서 정전기 쇼크에 의한 각종 전자제품의 오작동이나 파손 방지가 가능하게 되어 포장재, 자동차, 전자제품의 하우징 등으로 사용될 수 있게 된다. 현재까지 ESD 기능을 부여하기 위해서 사용되는 충전재로는 금속섬유, 금속플레이크, 탄소섬유, 카본블랙 등이 있으며, 최근 탄소나노튜브를 응용한 연구가 많이 진행되고 있는데 탄소나노튜브는 직경이 수십nm, 종횡비 1000이상의 나노섬유형태로 서 전기전도성이 구리수준으로 알려져 있고 소량을 충전할 시 기계적 특성도 오히려 증대하는 장점을 가지고 있으며 전기적 특성으로는 상대적으로 낮은 나노튜브 함량에서는 ESD를 들 수 있고 높은 함량에서는 전자파 차폐성까지 기대되고 있다. 본 연구에서는 우수한 인장강도, 기계적 강도, 열적 안정성, 내약품성을 가지면서 습식 또는 용융공정을 통해 용이하게 시트, 필름, 코팅제를 제조할 수 있는 방수, 투습방수성을 가지는 유연재료인 폴리우레탄(PU) 1액형 PU에 MWNT 함량이 3wt%인 IPA/MWNT 분산용액을 PU 함량 대비 20, 30, 40파트로 함유시켜 $120^{\circ}C$에서 2분 건조시켜 제조한 그라운드 필름에 2액형 PU와 IPA/MWNT 분산용액에 발포제를 첨가하여 발포온도 140, 150, $160^{\circ}C$에서 5분간 건조시켜 시료 필름을 제조하였다. 제조된 필름의 전기전도성 측정은 부피저항과, 표면저항을 각각 측정하여 확인하였으며, 필름의 마찰 대전압은 E.S.T-7 마찰 대전압 시험기를 이용하여 표면 마찰 대전압과 반감기를 측정하여 확인하고, 필름의 물리적 특성은 인장시험기를 이용하여 breaking stress, breaking strain을 구하였다. 필름의 표면 특성은 영상 현미경 시스템을 사용하여 ${\times}1000$ 배율로 측정하여 분산특성과의 연관성을 확인하였다.