• 대한수학회지
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• 제54권3호
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• pp.987-997
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• 2017

A deterministic model for the spread of pine wilt disease with asymptomatic carrier trees in the host pine population is designed and rigorously analyzed. We have taken four different classes for the trees, namely susceptible, exposed, asymptomatic carrier and infected, and two different classes for the vector population, namely susceptible and infected. A complete global analysis of the model is given, which reveals that the global dynamics of the disease is completely determined by the associated basic reproduction number, denoted by $\mathcal{R}_0$. If $\mathcal{R}_0$ is less than one, the disease-free equilibrium is globally asymptotically stable, and in such a case, the endemic equilibrium does not exist. If $\mathcal{R}_0$ is greater than one, the disease persists and the unique endemic equilibrium is globally asymptotically stable.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.70.1-70
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• 2003

It was investigated whether culture filtrates produced by X. fastiduosa could be used to determine varietal susceptibility in grape cultivars to anthracnose as a substitute for pathogen inoculation or field screening. Bioassay of grape leaves with culture filtrates showed that their phytotoxicities were active and host-selective. Ethyl acetate extracts from those also showed the toxicities and host selectivity among grape cultivars. The sensitive range of plants to culture filtrates and their ethyl acetate extracts was consistent with the host range to the pathogen. Susceptible cultivars were sensitive to even highly diluted culture filtrates but resistant cultivars were not affected even at original culture filtrates. Susceptible cultivars were sensitive to the undiluted culture filtrates than highly diluted culture filtrates and the younger leaves were the more sensitive to the culture filtrates and their ethyl acetate extracts in grapes.

• 미생물학회지
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• 제6권1호
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• pp.1-5
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• 1968

This experiment was undertaken the purpose of investigating the difference of the content of free amino acids in the diseased and healthy leaves of the resistance and susceptible rice varieties, to blast by means of paper chromatography. The results obtained are summarized as follows. (1) In the healthy and diseased leaves, the former was founded nine to tell sorts of free amino acids and later was observed eleven. In the both of leaves, alanine and valine were contained in larger amount, and aspartic acid, glycine and arginine were found relatively less in general. (2) In the diseased leaves, the amino acids were increased in quantity, especially glutamine and aspartic acid were remarkable, and cystine were found only in the diseased ones. (3) It seems to that the health leaves in all varieties were observed the amino acid contents, in notably increase and decrease, but in the diseased ones were not changed in amount. Tatacho, susceptible variety was more contained the amount of glutamine and aspartic acid than Zenith, resistance one.

• 식물병연구
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• 제10권3호
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• pp.203-208
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• 2004

붉은 고추 탄저병균의 우점종인 Colletotrichum gloeosporioides는 C. acutatum에 비해 병원성이 강하였다. C. gloeosporioides는 G와 R계통이 존재하였으며, G계통이 R계통보다 더욱 강한 병원성을 보였다. 붉은 고추 품종간의 병원성 검정 결과, 금세기 품종이 가장 감수성이었고, 파페트 품종이 가장 약한 감수성이었다. 참깨, 홍화, 마, 그리고 딸기와 같은 다른 기주에서 분리되어진 C. gloeosporioides는 붉은 고추에 감염을 일으켰다.

• International Journal of Industrial Entomology and Biomaterials
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• 제6권2호
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• pp.145-149
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• 2003

Seeing inadequate disinfection and unhygenic condition in rearing area, use of disease resistant silkworm variety is the best option. In order to this, an attempt has been made to develop the resistance to Bombyx mori densonucleosis virus (BmDNV-2) into a susceptible silkworm breed Zhenon1 by cross breeding with a resistant silkworm breed SU12 and exposing the subsequent generations to BmDNV-2 followed by the selection of individuals from the surviving batches. After seven generation the evolved DNV-2 resistant strain showed the significantly higher resistance to BmDNV-2 than control Zhenon1. The economic characters of both of the breeds were almost on par.

• Asian-Australasian Journal of Animal Sciences
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• 제8권1호
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• pp.13-16
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• 1995

In this study out of 3036 Black Bengal goats examined, 1755(57.80%) were infected with different types of metacestodes. The metacestodes were Cysticercus tenuicollis(54.54%), Coenurus cerebralis(6.32%) and hydatid cysts(11.13%). Animals > 18 months old were relatively more susceptible to Cysticercus tenuicollis and Coenurus cerebralis infection. On the contrary, animals > 8 months to 18 months old were more susceptible to hydatid infection, Both male and female goats were found to be equally infected with the metacestodes. A fully grown Coenurus cerebralis was also recovered from the abdominal muscles of a goat. In Cysticercus tenuicollis infection, pathological effects were not so marked. However, in few cases of Coenurus cerebralis infection the bones of the skull were found to become thin and soft. The hydatid cysts were found to develop in the vital organs by replacing the tissues, thus impairing normal functions.

• 한국응용곤충학회지
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• 제19권1호
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• pp.1-4
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• 1980

벼도열병균의 한 균주를 벼에 접종했을때 형성된 이병성병반 및 중도형병반에서 얻어진 단포자분리균주간의 병원성의 양적차이를 온실에서 조사하였다. 단일이병성병반에서 분리된 대부분의 단포자분리균은 단일중도형병반에서 분리한 균주보다 이병성병반형성율이 현저히 높았고 중도형병반 형성은 비슷하였다. 특히 중도형병반에서 분리한 균주가 저항성병반을 더 많이 형성하였다. 이들 두 단포자분리균주내에서도 형성된 병반수에 다소의 변이를 보였다.

• 한국응용곤충학회지
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• 제19권1호
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• pp.11-20
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• 1980

특정수도품종에 대한 도열병균의 침입률은 접종전처리온도와 균주의 조합보다는 공시균주나 온도의 단독요인에 의한 영향이컸다. 이병성품종은 그 품종이 어떤 온도조건하에서 자랐던지 또는 병원성이 다른 어떤 균주로 접종이 되었던지 이병성으로 남아 있었으며 접종전에 기주가 다른 온도조건하에서 자랐을 경우, 도열병균의 특정균주 또는 Race의 병원성발현은 다르게 나타나는 것이 관찰되었다.

• Corrosion Science and Technology
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• 제14권6호
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• pp.253-260
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• 2015

The pitting behaviours of 304L and 316L stainless steels were investigated at $3^{\circ}C$ to $90^{\circ}C$ in 1 M solutions of NaCl, NaBr and NaI by potentiodynamic polarization. The temperature dependences of the pitting potential varied according to the anion, being near linear in bromide but exponential in chloride. As a result, at low temperatures grades 304L and 316L steel are most susceptible to pitting by bromide ions, while at high temperatures both stainless steels were more susceptible to pitting by small chloride anions than the larger bromide and iodide. Thus, increasing temperature appears to favour attack by smaller anions. This paper will attempt to rationalise both of the above findings in terms of the point defect model. Initial findings are that qualitatively this approach can be reasonably successful, but not at the quantitative level, possibly due to insufficient data on the mechanical properties of thin passive films.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.475-482
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• 2005

Many public facilities including roadway, railway, and embedded pipe lines in this country have been damaged by the repeated freezing and thawing of the soil during winter and spring every year. However, there are only few research results in field of frozen ground in this country. Also, there are no the formulation of the reasonable equation for frost penetration depths and of the criterion for identifing potentially frost-susceptible soil in design manual of pavement yet. Through this study it is anticipated to asses the frost action problem in roadway, railway, and water suppply lines and to establish the design criterion about pavement in seasonal cold region.