• Journal of Forest and Environmental Science
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• v.34 no.5
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• pp.395-404
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• 2018

Since the mass mortality of Quercus mongolica has been first reported in Gyeonggi province at 2004, the disease spread rapidly over Korean peninsula annually. Ambrosia beetle (Platypus koryoensis) was known as the insect vector of oak wilt fungus, Raffaelea quercus-mongolicae, and control methods of the disease had mainly been focused on eradication of insect vector. However, for the efficient management of the disease, combined control methods for both of the pathogenic fungus and insect vector are strongly required. As one of the efforts to suppress the pathogenic fungus, antifungal activities of Streptomyces isolated from oak forest soil were assayed in this study. Optimum culture condition for the selected isolates was also studied, As a result, Streptomyces blastmyceticus cultured in PDB (Potato Dextrose Broth) at $25^{\circ}C$ for 1 week showed the strongest antifungal activity against oak wilt fungus. Mycelial growth inhibition rates (MGIRs) of Streptomyces isolates were compared on culture media supplemented with heated and unheated culture filtrates of S. blastmyceticus. MGIRs on culture media with unheated culture filtrates were generally higher than those on culture media with heated culture filtrates. Antagonistic mechanism to get involved in the inhibition of hyphal growth and spore formation of the pathogen is due to the antifungal metabolites produced by Streptomyces. This study will provide the fundamental information in developing biocontrol agents for the environment-friendly management of oak wilt disease.

• International journal of advanced smart convergence
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• v.6 no.3
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• pp.22-28
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• 2017

With the recent development of technologies to manage vast amounts of data, data mining technology has had a major impact on all industries.. Data mining is the process of discovering useful correlations hidden in data, extracting executable information for the future, and using it for decision making. In other words, it is a core process of Knowledge Discovery in data base(KDD) that transforms input data and derives useful information. It extracts information that we did not know until now from a large data base. In the decision tree, c4.5 algorithm was used. In addition, the C4.5 algorithm was used in the decision tree to analyze the difference between frequency and mortality in the region. In this paper, the frequency and mortality of percutaneous coronary intervention for patients with heart disease were divided into regions.

• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.217-223
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• 1995

Nature of graft transmissibility of pear abnormal leaf spot disease was examined by various grafting methods in the greenhouse and field. When the diseased and symptomless twigs were collected in winter and grafted in the next spring to the seed-originated healthy root stock, the abnormal leaf spot was developed only in the case of the diseased twigs. Double grafting on a seed-originated healthy root stock, where the diseased and the symptomless twigs were used as 1st and 2nd scions, respectively, developed abnormal leaf spot lesions without exception on the 2nd scions. Tongue-graft with the diseased and the symptomless trees also incited abnormal leaf spots on the both trees. Abnormal leaf spots of were also developed on HN-39, an indicator pear tree, used as a 2nd scion in a double graft test, where the diseased twig and a seed-originated healthy tree were used as the 1st scion and the root stock, respectively. When the diseased twig was top-grafted to the healthy root stock, lesion development of abnormal spot was limited to the grafted twig itself in the 1st year, but expanded to the main branches in the 2nd year, and spread over the whole tree in the 3rd year. This result indicates that the causal agent of abnormal leaf spot disease is transmitted by graft.

• Korean Journal of Organic Agriculture
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• v.18 no.1
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• pp.55-62
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• 2010

The study was conducted to investigate effects of different organic fertilizers on 'Niitaka' pear tree performances in a controlled greenhouse. The four 'Niitaka' pear seedling trees per treatment were grown in a greenhouse for 6 months. Each pot was filled with control, rice bran (RB), coffee bran compost (CBC), and the mixture (RCC) of RB + CBC + chitin incubated compost (CIC). Each pot was filled with 1:1:1 (v/v/v) of soil : sand : fertilizer, and control, RB, CBC, CIC, and RCC were applied as treatments. Root fresh weights and root activities were increased by all the organic fertilizers, especially by RCC. RCC treated trees had the highest tree height and thickest tree trunk, and all organic fertilized trees showed increased tree growth compared to the control. The more diseased and damaged degrees on the leaf by spider mites increased leaf falling rates on all the treatments. The reduced diseased and healthy leaves were found on RCC treated trees that had better tree performance. Also, all the organic fertilized trees seemed to prevent the occurrence of disease in the leaf. Therefore, the organic fertilizer applications could be a good strategy to obtain better tree performance and maintain healthy seedlings in the nursery market or young organic pear orchard.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.545-547
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• 1998

Scab disease of Aralia elata (Miq.) Seemann occurred severely in Kangwon province, Korea. First, brown spots were formed on leaves and enlarged along vein. The infected leaves including petiole and midrib were twisted forming scab and died eventually. Also the disease infected twigs and trunks of the tree forming scab. Conidia, ascospores and asci developed in locule were observed in the infected tissue. The causal organism of the scab disease of Araliae elata was isolated and identified as Elsinoe araliae Yamamoto (imperfect stage: Sphaceloma araliae Jenkins) based on the morphological and cultural characteristics, and pathogenic test.

• 한국데이터정보과학회:학술대회논문집
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• 2001.10a
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• pp.76-78
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• 2001

Variable selection in oriental medical research is considered. Decision tree analysis algorithms such as CHAID, CART, C4.5 and QUEST have been successfully applied to a medical research. Paralysis disease is a highly dangerous and murderous disease which accompanied with a great deal of severe physical handicap. In this paper, we explore the use of CHAID algorithm for selecting variables for evidence-diagnosis of paralysis, disease. Empirical results comparing our proposed method to the method using Wilks $\lambda$ given.

• Environmental Engineering Research
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• v.23 no.4
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• pp.430-441
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• 2018

The adverse health impact of air pollution is becoming more serious. The purpose of this study is twofold: One is to analyze the effect of air pollution and temperatures on human health by analyzing the number of deaths from cardiovascular disease in Seoul, Korea; the other is to determine what impact the location of a monitoring site has on the results of a health study. For this latter purpose, air pollution and temperature monitors are sited at three locations termed green, public, and residential. Then, a decision tree model is used to analyze factors linked with deaths occurring at each monitoring site. The results show that the environmental temperatures before death and the $PM_{2.5}$ concentrations on the day of death are highly linked with the number of deaths regardless of the monitoring location. However, results are most accurate with residential data. The results of this study can be used as base data for a similar analysis and ultimately, as a guide to minimize the health impact of air pollution.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.80-83
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• 2008

Anthracnose symptoms were frequently observed on fruits of peach trees grown in Yeongi in Korea during disease survey in August from 2000 to 2005. The disease incidence was as high as 40% at its maximum in the orchards investigated. A total of 24 isolates of Colletotrichum species were obtained from the anthracnose symptoms, out of which 20 were identified as Colletotrichum gloeosporioides and the four remaining ones as C. acutatum based on their morphological and cultural characteristics. Two isolates of each C. gloeosporioides and C. acutatum caused anthracnose symptoms on the fruits by both wound and unwound inoculation, which were similar to those observed in the orchard. The symptoms appeared more rapidly by the wound inoculation than by the unwound inoculation. There was no difference in pathogenicity between the C. gloeosporioides and C. acutatum isolates tested. In Korea, only C. gloeosporioides has been recorded as the causal fungus of anthracnose of peach tree. This is the first report that C. acutatum also causes anthracnose of peach tree in Korea.

• KIEAE Journal
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• v.14 no.5
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• pp.49-57
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• 2014

This research is about analysis and evaluation of biodiversity of Suwon's street tree, then understanding the problem of it and finally finding a solution. Because the increasing damage of the street trees by disease and insects, insecticide is applied to prevent further damage. However, this insecticide is found to be cancer genic and causing hygienic threat to civilians. Therefore, by gathering Suwon's internal statistics about Suwon's street tree, the trees are divided into three categories, tall evergreen trees, deciduous trees, shrubs following Frank's 30-20-10 theory(1990). Also, according to species diversity index, the problem of disease and insect is researched in terms of biodiversity, and here we suggests solutions to counter such problems. According to the results, the trees planted in Suwon was found to be 31 families, 43 genus and 58 species. The most used kinds, almost 85% of the whole species, are found to be Rhododendron indicum (L.) Sweet, Buxus koreana Nakai ex Chung & al, Euonymus japonicus Thunb, Ligustrum obtusifolium Siebold & Zucc. Besides these, the rest of 15% of street trees had little variety. Therefore, it is necessary to plant tree variously and equally in terms of biodiversity. If this Frank's 10-20-30 solution is not enough to completely solve coulure problem, then further research will be done on soil properties, and local features for improvement of Suwon street tress.

• Journal of Sericultural and Entomological Science
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• v.13 no.1
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• pp.17-22
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• 1971

A series of experiments were conducted from 1968 to 1970 to find the transmission effects of the dwarf disease of mulberry tree in connection with inlay grafting and insect vector with the following conclusions: 1. The inlay-grafting of sound scions on diseased roots showed a 30 per cent transmission rate among the successful grafts. The inlay-grafting of diseased scions on sound roots showed a 14 per cent transmission rate among the successful grafts ir the case of scions cut and stored before wintering but no transmission effect in the case of scions prepared after wintering, There were some stocks, among the unsuccesful grasfts of diseased scions upon sound roots, that sprouted out new buds, no transmission effects were found in them, 2. Leafhoppers (Hishimonus disciguttus Walker) collected from areas with no dwarf disease infection were grouped into three plots and let to feed on mulberry tree severely infected by dwarf disease for 7 days, 14 days and 21 days respectively. After these preliminary treatment, the leafhoppers were recollected to be fed on the sound seedling divided into three plots for 10 days, 15 days and 20 days respectively to find the transmission effects. The results are that the 7 day plot showed no transmission effect whereas the 14 day plot showed a 22 per cent disease rate and the 21 day plot 61 per cent rate indicating that the longer the feeding period is the higher the transmission rate.