• Asian Journal of Turfgrass Science
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• v.22 no.2
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• pp.179-184
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• 2008

Host plants of Ectinohoplia rufipes (Mitschulsky) were investigated in golf courses in Gapyeong, Gyeonggi. Ten plant species in 7 families were observed to be fed on from golf courses. Thus, total number of host plants of Ectinohoplia rufipes were 94 species in 30 families. Rhododendron indicum and Rhododendron japonicum for. flavum in Ericaceae, Euonymus alata for. ciliato-dentatus in Celastraceae, Ulmus davidiana for. suberosa in Ulmaceae, Malus pumila var. dulcissima and Malus baccata in Rosaceae, Weigela florida for. subricdor in Caprifoliaceae, Betula platyphylla var. japonica in Betulaceae, Salix purpurea var. japonica in Salicaceae, and Quercus palustris in Fagaceae were newly listed host plants of Ectinohoplia rufipes in golf courses. Betula platyphylla var. japonica, Malus pumila var. dulcissima and Quercus palustris were heavily damaged host plants of Ectinohoplia rufipes.

• Nuclear Engineering and Technology
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• v.43 no.3
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• pp.271-278
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• 2011

When performing fire PSA in a nuclear power plant, an event mapping method, using an internal event PSA model, is widely used to reduce the resources used by fire PSA model development. Feasible initiating events and component failure events due to fire are identified to transform the fault tree (FT) for an internal event PSA into one for a fire PSA using the event mapping method. A surrogate event or damage term method is used to condition the FT of the internal PSA. The surrogate event or the damage term plays the role of flagging whether the system/component in a fire compartment is damaged or not, depending on the fire being initiated from a specified compartment. These methods usually require explicit states of all compartments to be modeled in a fire area. Fire event scenarios, when using explicit identification, such as surrogate or damage terms, have two problems: (1) there is no consideration of multiple fire propagation beyond a single propagation to an adjacent compartment, and (2) there is no consideration of simultaneous fire propagations in which an initiating fire event is propagated to multiple paths simultaneously. The present paper suggests a fire propagation equation to identify all possible fire event scenarios for an explicitly treated fire event scenario in the fire PSA. Also, a method for separating fire events was developed to make all fire events a set of mutually exclusive events, which can facilitate arithmetic summation in fire risk quantification. A simple example is given to confirm the applicability of the present method for a $2{\times}3$ rectangular fire area. Also, a feasible asymptotic approach is discussed to reduce the computational burden for fire risk quantification.

• Journal of Korean Society of Forest Science
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• v.78 no.3
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• pp.302-313
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• 1989

To investigate the effects of forest fire on the change of vegetation and soil conditions by the lapse of time, the 5th soil survey and vegetation analysis were carried out in July of 1988 at the rocky areas of Mt. Kwanak, where ground fire broke out 5 years ago. Three-year increasing trends of organic matter content, the value of pH, and total nitrogen content stabilized after the restoration of the vegetation. By the comparison of the occurrences of the species for 5 years after the forest fire, woody and herbaceous plants were categorized into 4 groups, i,e., invasive, sensitive, tolerant, and neutral species to the forest fire. Although such diversity indices as the species diversity and similarity index indicate that the restoration of damaged vegetation to the original species composition was proceeded for the period, the restoration of vegetation to the original crown closure and tree growth was not proceeded yet.

• Korean journal of applied entomology
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• v.41 no.1
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• pp.33-41
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• 2002

The mirid bug damages on grapevine were observed not only on young shoot and leaves (decoloration, deforming, and perforation) but also on fruits (black spot, corky scar, and young fruit shattering). Among 159 fields surveyed throughout the country, 113 fields (71%) were damaged, and the damages were relatively severer in the chief producing districts of grape vine, such as Gimpo, Anseong, Naju, Gimcheon, Buyeo, Daejeon, Yesan than other districts where grapevine yards were not concentrated. The severest shoot damages were observed in two grape vine yards of Naju (85%) and Gimpo (65%) in 1999. Three species of virid bugs were recognized on grape vine tree, Apoygus spinolae (Meyer-Dur), Apolygus lucorum (Meyer-Dur), and Orthotylus (Melanotrichus) flavosparsus(Sahlberg). Among them, A. spinolae was dominant species in the number of specimens collected. A. spinolae were collected on 10 host plants including Vitis vinifera L., Prunus armeniaca var. ansu Max., and prunus serrulata var. spontanea(Max.) Wils. and etc., and A. lucorum were collected on 10 species of plants, including Artemisia iwayomogi Kitamura, Artemisia princeps var. orientalis(Pampan) Hara and etc. Both A. spinolae and A. lucorum distributed widely in Korean grapevine yards.

• The Korean Journal of Zoology
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• v.13 no.1
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• pp.3-8
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• 1970

1. Paju area of Kyonggydo has received serious damages by Dryocosmus kuriphilus Yasumatsu in the bushes of Castanea crenata S. et Z. since 1965. I have also found the middle parts of whole country of Korea has damaged by this wasp. 2. Bobwonri was the worst case in its damage by Dryocosmus kuriphilus Yasumatsu with most prosperous parasite, Aletia flavostigma singularis Butler and Dictyoploca japonica Moore. I conclude that this is the result of the lack of beneficial insects and isolated bush formation. 3. The chestnut bush at Bunsuri was recovering from the damage of gall wasp nevertheless it was illustrated big damage at last year's hranches. I conclude that this recovering phenomena is closely related with the insect fauna of this area and this characteristic insect fauna was derived from the bush formation which reveals specific bush arrangement that can be illustrated as surrounded by another bush of Quercus acutissima Carruthers. 4. As a final conclusion, I recommend mixed bush formation of chestnut tree with Quercus species to control insect population dynamics in healthy status.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.1080-1083
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• 2005

Can speak that DTD is meta data that define meaning of expressed data on XML document. Therefore, in case DTD information is damaged this information to base security of XML document dangerous. Not that attach digital signature on XML document at send-receive process of XML document in this research, proposed method to attach digital signature to DTD. As reading DTD file to end first, do parsing, and store abstracted element or attribute entitys in hash table. Read hash table and achieve message digest if parsing is ended. Compose and create digital signature with individual key after achievement. When sign digital, problem that create entirely other digest cost because do not examine about order that change at message digest process is happened. This solved by method to create DTD's digital signature using DOM that can embody tree structure for standard structure and document.

• Research in Plant Disease
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• v.24 no.4
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• pp.249-256
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• 2018

Disease occurrence in apple cultivars on 13-30 apple orchards from April to October 1992-2010 was investigated at 30 days intervals in Gyeongbuk, Gyeongnam and Jeonbuk provinces of Korea. Apple cultivar 'Fuji' was found most susceptible and is being damaged by cedar apple rust, scab, gray mold, Alternaria blotch and Marssonia blotch as major leaf diseases that were observed. The percentage of occurrence of these leaf diseases varies from every year. This variation is based on different rainfall and temperature conditions, cultivation, root stock and changed system of fungicide spray during the particular year and season.

• Journal of Korean Society of Forest Science
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• v.109 no.3
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• pp.259-270
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• 2020

Extreme weather events, such as heat and drought, have occurred frequently over the past two decades. This has led to continuous reports of cases of forest damage due to physiological stress, not pest damage. In 2014, pine trees were collectively damaged in the forest genetic resources reserve of Sogwang-ri, Uljin, South Korea. An investigation was launched to determine the causes of the dieback, so that a forest management plan could be prepared to deal with the current dieback, and to prevent future damage. This study aimedto 1) understand the topographic and structural characteristics of the area which experienced pine tree dieback, 2) identify the main causes of the dieback, and 3) predict future risk areas through the use of machine-learning techniques. A model for identifying risk areas was developed using 14 explanatory variables, including location, elevation, slope, and age class. When three machine-learning techniques-Decision Tree, Random Forest (RF), and Support Vector Machine (SVM) were applied to the model, RF and SVM showed higher predictability scores, with accuracies over 93%. Our analysis of the variable set showed that the topographical areas most vulnerable to pine dieback were those with high altitudes, high daily solar radiation, and limited water availability. We also found that, when it came to forest stand characteristics, pine trees with high vertical stand densities (5-15 m high) and higher age classes experienced a higher risk of dieback. The RF and SVM models predicted that 9.5% or 115 ha of the Geumgang Pine Forest are at high risk for pine dieback. Our study suggests the need for further investigation into the vulnerable areas of the Geumgang Pine Forest, and also for climate change adaptive forest management steps to protect those areas which remain undamaged.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.190-211
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• 2010

The purpose of this paper is to provide the preliminary data for maintenance of old trees of natural monuments and establishing protection projects. Accordingly, growth conditions, location circumstances, environment and protection management were analyzed for old trees at 34 sites in Gyeongsangbuk-do. Tree forms, crown, trunk and trees' health, leaves volume were analyzed in survey sites. As the results, the growth of Picrasma quassioides in Songsadong, Andong-si and Catalpa ovata in Hongwon-ri, Cheongsong-gun were not in good condition, along with other old trees of 6 cities (Quercus variabilis in Susan-ri, Uljin-gun, Juniperus chinensis in Hujeong-ri, Uljin-gun, Pyrus ussuriensis in Ssangjeon-ri, Uljin-gun, Salix glandulosa var. pilosa in Deokchon-ri, Cheongdo-gun, Pinus densiflora for. multicaulis in Hwasan-ri, Mungyeong-si, Pinus densiflora in Daeha-ri, Mungyeong-si). Accoding to these results, protection project and consistent monitoring are necessary. The analysis results of growth conditions per location circumstances showed that the old trees in the small spaces with large traffic of people were in bad condition. Therefore, it is necessary to secure sufficient space and soil improvement for such trees. The analysis results of growth conditions per species showed that Zelkova serrata, Quercus spp., Pinus densiflora are in good condition while Salix koreensis and others, i.e. a singular tree, are in poor condition. Thus, relatively smaller individuals and separately situated trees need careful management in their protection. The analysis results of trunk's growth ratio showed that Pinus densiflora, Ginkgo biloba, Zelkova serrata are in good condition whereas Juniperus chinensis, Quercus variabilis, Salix koreensis are not. It is a recent trend that tree surgeries are gradually decreasing; there are a number of damaged trees with no maintenance/management, and several sites requiring mend trunks management and cabling, bracing in protection and management projects. Hence, in the future, local government and management organizations should plan for systematic management and establish a protection plan for the natural monument trees. Also, 12 sites were found to be in need to purchase lands in order to secure the growth spaces, and since most of these areas are available for purchase, it is needed to promote a budget and purchase those areas through persuasion of the owner. These areas seems crucial in order to maximize the effect of conservation efforts and budgets for the preservation and restoration of the old trees.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.1
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• pp.118-128
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• 2016

The purpose of this study is to present efficient methods of preserving and managing the fish shelter forest in Mulgun-ri on the southern coast of Korea on the basis of its humanistic, sociological and ecological characteristics. The study object is Korean natural monument No. 150, which is presumed to have been forested by descendants of Jeonju Lee Family who settled there, and village rituals are held every October to pray for the peace of the village. The forest is managed by Namhae-gun as a historical and cultural resource as well as its disaster-preventing, economic, and environmental and ecological functions. The linear form of the area is $23,962.6m^2$ and farmland(48.5%) and urbanization area(38.2%) are extensively located in its periphery area. Actual vegetation was sub-classified into three types of land according to use pressure and whether or not damage was done: land where its stratification was formed; land where it was restored, and the land where it was damaged. Plant communities were sub-classified into Aphananthe aspera community(I) and Zelkova serrata community(II) which had a low use pressure; Z. serrata-Chionanthus retusa-A. aspera community(III) and A. aspera-Z. serrata community(IV) which had a high use pressure; and Celtis sinensis-A. aspera community(V) whose underlayer was damaged by use. Fragmentation of the forest is under way and its inside vegetation growth is hampered due to the installation of traffic and resting facilities such as the through roads costal roads, wooden-deck walkways, parking lots, washstands, etc. As a restoration management plan for this, the following were required: an establishment of preferred restoration area; a selection of restoration vegetation species; and an appropriate restoration method. The damaged area($7,868.2m^2$) will have to be set up as the preferred restoration area; seedlings of restored vegetation species should be raised with dominant species within the forest(i.e., Z. serrata, A. aspera, C. sinensis, and C. retusa) as their 'mother trees' for the benefit of for the next-generation forest; and sub-tree and shrub layer should be complementarily planted with 5 and 115 trees(unit $100m^2$) respectively to facilitate the formation of a multi-layered vegetation structure. In addition, resting facilities scattered inside the forest should be demolished; and indiscriminate use of them should be controlled; management and monitoring should be carried out so that the area can be preserved and restored as a deciduous broad-leaved forest.