• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.895-899
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• 2009

실제 하천에서는 지형적 이산화에 따른 복잡성으로 인해 마름/젖음 현상이 발생하며 그로 인해 작은 수심에서 수치해석의 안정성에 영향을 주어 해석을 불가능하게 한다. 자연수로는 저수시 및 평수시에 물을 소통시키는 주수로부와 홍수시 수위 상승에 따라 주수로부에서부터 범람하게 되는 홍수터로 구성된다. 홍수터는 홍수류의 일시적인 저장이나 하류로 흐름을 전달하는 복합수로의 부분으로 사용된다. 자연수로에서 이와같은 흐름구조는 불규칙한 단면형상, 조도계수 등에 의해서 더욱 복잡하게 나타난다. 본 연구에서는 복잡한 지형과 자연 하천구조에 대한 동역학적인 흐름특성을 해석하고 오염물질의 이송-확산 해석 및 토사이송 해석과 연계하기 위해서 개발된 RAM-2 모형에 동수역학적 해석을 실시하였다. RAM-2 모형에는 대상하도에 대한 마름/젖음의 처리를 위해 흐름의 시간별 수위상승 및 하강 속도를 고려한 Deforming Grid 기법을 적용하였으며, 이에 대한 적용성을 검토하기 위해 마름/젖음 조건을 가지는 실험수로와 홍수터를 가진 사다리꼴 단면 그리고 실제 하도에 대해 적용하여 그 결과를 살펴보았다.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.7 no.6
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• pp.33-38
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• 1986

한 해의 농사를 마무리짓는 이 시점에서 ''86년도 병해발생상황을 살펴본다는 것은 내년도의 방제계획을 보완한다는 점에서 매우 뜻깊은 계기가 될 것이다. 금년은 매우 특이한 기상으로 초봄에는 충분한 강우로 이앙을 순조롭게 마칠 수 있었으며 이앙초기에는 평년에 비하여 약간 기온이 높았지만 병해초발은 예년과 같이 시작되었다. 그러나 6월 하순과 7월의 저온으로 본논의 초기 및 중기 병해발생은 아주 적은 편이었지만 생육후기에는 잦은 강우로 이삭도열병, 흰잎마름병 등의 발생량이 증가한 반면에 잎집무늬마름병 발생은 아주 적은 해였다. 중$\cdot$만생종 출수기에 특히 남부지방에서 문제시되었던 것은 태풍 Vera호의 건풍동반으로 백수현상이 지역적으로 심한 발생을 보여 수고성 및 흰잎마름병 발생에도 영향을 주었을 것으로 생각된다. 여기서는 금년도 주요병해의 발생특징을 분석해 보고 문제점을 잘 파악하여 내년도의 방제자료로 삼고자 한다.

• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.202-208
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• 1996

1986년부터 1992년까지 전라북도와 경상남도에서 수집된 벼 흰잎마름병균 66균주를 국내의 4 판별품종에 대한 병원성을 조사한 결과, K1 균형이 18(27.3%) 균주, K2 균형이 2(3.0%)균주, K3 균형이 18(27.3%) 균주가 분리되었다. 그러나 K4는 발견되지 않았으며 2균주는 균형을 분류할 수 없었다. 이들 2균형은 5종류의 일반계 품종에 대한 병원성에 따라 19종류의 group으로 세분되었다. 국내 벼 흰잎마름병 균주는 일본이나 IRRI 판별품종과 동일한 유전자를 갖는 NIL로 균형이 분류되지 않는 균주가 각각 63.6%, 57.6%나 되어, 국내 벼 흰잎마름병균은 일본 및 IRRI 균형과 비교하기가 곤란하였다.

• 농업기술회보
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• v.49 no.4
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• pp.21-22
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• 2012

벼 흰잎마름병은 벼에 발생하는 중요한 세균병 중 하나로 우리나라 벼 재배에서 가장 큰 피해를 주고 있다. 한 번 발생하면 치료가 힘든 병으로 알려져 있어 예방위주로 철저히 방제해야 수량감소와 쌀의 품질저하를 막을 수 있다.

• Current Research on Agriculture and Life Sciences
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• v.18
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• pp.9-17
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• 2000

In an effort to breed lines resistant to both bacterial wilt and Phytophthora blight, F5 and BC1F4, and F6 and BC1F5 generations of the crosses between the lines previously bred for resistance to Phytophthora blight ((16-2-2-3-2 = Phytophthora-resistant 'Kalmi', 19-1-3-7-1-1, 19-2-4-5-3-2 = Phytophthora-resistant 'Subi', Kim et al., 1996) and sources of resistance to bacterial wilt (KC350 = MC-4 or KC353 = PBC631, Kim et al., 1998) were evaluated for resistance to both bacterial wilt and to Phytophthora blight in 1999 and in 2000, respectively. Plants which were highly resistant to both bacterial wilt and Phytophthora blight were selected for development of the next generations.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.7
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• pp.1221-1228
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• 2016

In this paper, we propose a modified rhombus slot UWB(Ultra Wide Band) antenna with fork-shaped feeding structure. The proposed antenna is modified rhombus slot structure and fork-shaped feeding structure to get ultra-wideband characteristics for UWB communication. Modified rhombus slot structure consists of slot shaped which eliminated upper and lower part of the basic rhombus slot. The antenna is designed on an FR-4 substrate of which the dielectric constant is 4.4, and its overall size is $34mm(W_1){\times}34mm(L_1){\times}1mm(t)$, and its slot antenna size is $30mm(W_2){\times}16.75mm(L_3+L_4)$. After carrying out the simulation of each parameters, optimized values are obtained. From the fabricated and measured results, return loss of the proposed antenna satisfied Return Loss -10dB in 3.1 ~ 10.6 GHz. And measured results of gain and radiation patterns characteristics displayed for operating bands.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.117-124
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• 2010

Turfgrass survival and ocurrence of brown patch disease during summer season were investigated the forty six cultivars of cool season grasses in 6 species, popularly used in golf courses in Korea. Ocurrence of brown patch disease was evaluated two times in July. The percentage of turfgrass survival was investigated on Aug. 20 and on Sep. 20 in 2010. There were significant difference for the percentage of turfgrass survival and brown patch disease occurrence among cultivars. Brown patch disease caused by Rhizoctonia spp. and Pythium aphanidermatum with rDNA ITS were showed most susceptible in creeping bentgrass (Agrostis palustris Huds) cultivars and chewings fescue (Festuca rubra var. commutata Gaud) cultivars. The percentage of turfgrass survival during August to September was showed lower creeping bentgrass cultivars and chewings fescue cultivars than another cultivars. Among of 20 cultivars in Kentucky bluegrass (Poa pratensis L.) species were showed highest survival in cultivars of "Nuglade", "Cabernet", "Midnight II" and "Beyond". 6 cultivars of Tall fescue (Festuca arundinacea Schreb) were showed highest survival in cultivars of "Double sentry", "Inferno", and cultivars of "Accent II" in Perennial ryegrass (Lolium parenne L.) species.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.93-98
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• 1991

This research was undertaken to clarify derivation of resistance of Japonica type of rice varieties to rice strip virus. 1. The source of resistance to the rice strip virus in rice cultivars of Nagdongbyeo, Hwaseongbyeo, Gwangmyeongbyeo, Yeongdeogbyeo, Dongjinbyeo, Gyehwabyeo, Hwacheongbyeo, Suweon 362, Iri 390, Milyang 64, Milyang 96 and Milyang 101 was derived from rice cultivar of Modan. 2. The resistance of rice cultivars Donghaebyeo, Sinseonchalbyeo, Palgongbyeo, Hwajinbyeo and Somjinbyeo to the rice strip virus was derived from cultivar Milyang 23 and/or Nangdongbyeo. 3. The resistance of cultivars Jinjubyeo, Tamjinbyeo and Yongsanbyeo to the rice strip virus was derived from cultivar HR 769 and/or Milyang 20. 4. The resistance of cultivar Daecheongbyeo to the rice strip virus was deriverl from cultivar Nagdongbyeo and/or HR 769.

• Journal of Korea Water Resources Association
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• v.42 no.11
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• pp.973-988
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• 2009

The objective of this study is to develop an accurate and robust two-dimensional finite element method to simulate drying and wetting in complex natural rivers. The Dry/Wet algorithm developed in this study is Grid Reconstruction Method which requires the definition of new meshes and renumbering of the nodes. Any drop of water level in the two-dimensional domain results in eliminating nodes and elements. Several numerical simulations were carried out to examine the performance of the Grid Reconstruction Method for the purpose of validation and verification of the model. The accuracy and application of the developed model are verified by comparing simulated results with observed values.

• Journal of Bio-Environment Control
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• v.18 no.2
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• pp.171-176
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• 2009

Hydroponic culture has been developed to control soilborn diseases, to increase yield and to enhance the quality of vegetable, The pathogen could be detected from infected plant materials, hydroponic tanks, culture solution and solid media of the severely infected greenhouse, The density of pathogen population was coincided with the severity of disease incidence, For example, 1,900cfu m$L^{-1}$ pf pathogens were counted from tomato plants sampled in a 20% diseased greenhouse. The pathogens may be introduced in the greenhouse through the contaminated soil surrounding the house and/or through the infected young seedlings grown on the nursery soil. Also, not detected to Ralstonia solanacearum from tomato seeds (House Momotaro, Bbaebbae, Ggoggo, and Minicarol cultivar) selling at a market.