• Korean Journal of Organic Agriculture
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• v.25 no.3
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• pp.587-602
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• 2017

Correlations of soil and leaf nutrients and growth of young 'Enterprise' apple (Malus ${\times}$ domestica Borkh.) trees were analyzed with tree damage, such as Japanese beetle (JB; Popillia japonica Newman)-damaged leaves, vole damage to trunk, tree mortality, and weed density in a certified organic orchard in warm and humid environment of Southern USA. Interaction treatments of four mulch and three fertilizers were applied around trees as follows: mow-and-blow (MB), shredded paper (SP), wood chips (WC), and green compost (GC) as a mulch, with no fertilizer (NF), poultry litter (PL), and commercial organic fertilizer (CF) as a fertilizer applied in April. Vole damage to trunk and weed density were little correlated with mineral nutrients and tree growth. JB-damaged leaves were highly stimulated to 26.5% in GC-treated plots while tree mortality were increased by MB treatments. Biomass production per tree was approximately 3,700 g on the WC- and GC-treated plots, which was two times higher than those values observed on the other two mulch plots. JB-damaged leaves tended to get worse when nutrients in soil and leaf increased through the correlation analysis, with a strong positive relationship ($r^2=0.585$) observed between JB-damaged leaves and trunk cross sectional area, a vegetative indicator. Tree mortality was more negatively associated with nutrient contents and growth of trees than those of soil nutrients. Wood chips was considered for a local organic mulch materials to increase organic matter contents and to produce healthy young trees in Southern USA, with control insect, such as beetle, and vole density in an orchard habitat.

• International Journal of Industrial Entomology and Biomaterials
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• v.40 no.2
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• pp.41-50
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• 2020

Vermicompost, manure, compost and organic fertilization are ecofriendly. Nowadays, many products resulted from sericulture consumed by humans such as mulberry leaves, fruits, mulberry tea, silk and natural silk cosmetics. Soil applications of three treatments with vermicompost (0.5, 1 and 2 tons per 0.42 hectare) and recommended rate of mineral fertilizers of nitrogen phosphorus potassium were used for investigation. Impact of fertilization on mulberry plant traits of moisture, number of shoots/tree, total shoots length/tree, number of leaves/shoot, number of leaves/ (100g), leaf yield/tree and leaf yield of fadden/season were recorded. In addition the effect of fertilization on larval and cocoon characters of young instar duration, fifth instar duration, total larval duration, larval mortality percentage, weight of third instar larvae, weight of fourth instar larvae, weight of fifth instar larvae, fresh cocoon weight, fresh shell weight, pupae weight, cocoon shell ratio, silk productivity, cocooning percentage, pupation ratio, number of cocoons/ liter, crop cocoons by number, crop cocoons by weight, fecundity and fertility. Using vermicompost treatment was enhancing plant characters. Treatments of V₃, V₂ and V₁ were shortage young, fifth and larvae durations. Mostly feeding silkworm during the whole larval duration on treated mulberry leaves with vermicompost improving the traits average. Using vermicompost for fertilization by rate of V₃ and V₂ is better than others for cocoon characters for females and males.V₃ and V₂ of vermicompost per 0.42 hectare is recommended for rearing mulberry silkworm instead of mineral fertilization.

• Proceedings of the Costume Culture Conference
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• 2005.10a
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• pp.127-131
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• 2005

• Journal of the Korean Wood Science and Technology
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• v.49 no.5
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• pp.482-490
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• 2021

This research was conducted to analyze the sound absorption effect of air-dried leaves from two evergreen tree species found in Korea's warm-temperate and subtropical regions. As eco-friendly sound absorption materials, Dendropanax morbiferusa, and Fatsia japonica leaves were prepared in three specimen units sizes 0.5 × 0.5 cm², 1.0 × 1.0 cm², and 2.0 × 2.0 cm², and each of them was formed at a thickness of 1.00 cm, 1.75 cm, and 2.50 cm. The measured sound absorption coefficients (SAC) for 18 conditions were comparatively analyzed in this study. The SAC of both tree species was significantly improved by increasing the dried leaf layer thickness. These results showed a more consistent and distinct trend for both tree species under the condition of 0.5 cm² in dried leaf size compared to other leaf specimen sizes. However, as the thickness increased, the difference in sound absorption effect according to the leaf size tends to decrease overall. In the case of D. morbiferus, there was no significant difference in SAC based on leaf size under the condition of 2.5 cm thickness (p < 0.05). The highest mean SAC was found in a 2.5 cm thick condition with a leaf size of 0.5 × 0.5 cm², 0.549 for D. morbiferusa, and 0.594 for F. japonica, respectively.

• Plant Disease and Agriculture
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• v.1 no.2
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• pp.26-28
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• 1995

Anthracnose of tea tree, Camellia sinensis, occurred severely at tea plantation of Boseung, Chonnam. Irregular, dark brown spots appeared on tips and margins of mature leaves in early stage. As the disease progresses, the lesions were covered with numerous, small, black, slightly raised pustules (acervuli). The causal fungus of anthracnose was identified as Colletotrichum theae-sinensis (Miyake) Yamamoto. Symptoms by C. theae-sinensis appeared around 20 days after artificial inoculation.

• The Korean Journal of Ecology
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• v.19 no.6
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• pp.529-541
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• 1996

During the period of December 1992 (winter-spring) and from February 1995 (winter-spring), the leaf processing rates of oak (Quercus serrata) and tulip (Liriodendron tulipifera) tree was investigated in the headwater streams in southeastern part of Korea in conjunction with the distribution pattern of macroinvertebrate fauna. Using two types of bags ($10\times30cm$ with 5 g of dry leaves; open bag with holes, closed bag without holes), decomposition rates of oak and tulip tree by shredder and/or microbiota at a reatively undisturbed 2nd-order stream were compared, Regardless of leaf type, leaves in the open bage decomposed slightly faster than those in the closed bags. In the 1992 experiment, osk leaves decomposed much slower than tulip leaves (after 138 degree days, osk : closed, 0.006% loss/day ; open, 0.008 ; tulip: closed, 0.021 ; open, 0.023; n=2). The of the first experiment using oak leaves in 1995 were similar to those of the first experiment (after 151 degree days, oak: closed, 0.005% loss / day; open, 0.006; n=6). Over 50% of invertebrates from 122 leaf pack samples collected from 12 streams during the winter period of 1994 were identified as shredders (shredder, 56.2; collector, 32.7; scraper, 8.65; predator, 2.45%). Among shredders, Gammarus sp. and Tipula sp. were dominant species in terms of number and biomass (8.2 ind./g, 1.0 ind./g AFDW of leaves). Among many physico-chemical parameters, the width of stream channel was found to be the most influential factor in the distribution of Gammarus and Tipula (Gammarus: r=-0.34, P<0.001;Tipula:r=0.40, P<0.001). Considering the fact that oak is one the dominant riparian vegetation in the southeastern part of korea, the patterns of oak processing and shredder distribution shown in theis study may well represent some of the important characteristics of headwater steams in southeastern Korea.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.7 no.1
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• pp.18-24
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• 1982

The Tree phenomenon of the PMMA resin depends on an annex of the inorganic fillers and water. If the internal of an arganic insulating materials exist the fault of inorganic fillers, Void and Projecting part, the high voltage concentrates in this place. It leaves a trace about the partical breakdown and this phenomenon develops into the degration of insulating material. This paper researchses that have an effect on the tree phenomenon by the inorganic fillers and water. The results is as follow. (1) The growth of tree are less the influence of inorganic fillers. Because , the constant of water are more. (2) If the tree branches contact the inorganic filler, the advance are relaxation.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.4
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• pp.384-395
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• 2012

This study was performed to develop the source profiles for fine particles ($PM_{2.5}$) emitted from the biomass burning. The multi-method research strategy included a usage of combustion devices such as field burning, fireplace, and residential wood burning to burn rice straw, fallen leaves, pine tree, and oak tree. The data were collected from multiple sources and measured water-soluble ions, elements, elemental carbon (EC), and organic carbon (OC). From this study, it turned out that OC (34~67%) and EC (1.2~39%) are the major components emitted from biomass burning. In the case of burning rice straw at field burning, OC (66.6%) was the most abundant species, followed by EC (4.3%), $Cl^-$ (3.6%), Cl (2.1%), and $SO^{2-}_4$(1.9%). Burning rice straw, fallen leaves, pine tree, and oak tree at fireplace, the amount of OC was 58.5%, 52.7%, 52.5%, and 61.2%, and that of EC was 1.2%, 18.4%, 36.5%, and 2.7%, respectively. The ratio of OC for the burning of pine tree and oak tree from the residential wood burning device was 56.9% and 34.3%, and that of EC was 25% and 38.6%, respectively. Applying the measured data with respect to the proportion of components emitted from biomass burning to reference model, it turned out that self-diagnosed result was appropriate level, and the result based on the model is in highly corresponding to actual timing of biomass burning.

• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.611-616
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• 2010

To explore on the defense strategies against hervivory of broadleaved tree species growing in tropical rain forest, Solomon Islands, morphological characteristics of the leaf, leaf domatia structure and the number, herbivores insects and mites on the leaves of 26 tree species, collected from the trees growing in Guadalcanal, New Georgia, and Tetepare islands, were investigated from Feb. 25 to March 5, 2010. The results are summarized as follows. Six tree species including Terminalia catappa(23.08%) among total 26 species have domatia structure. Especially, domatia of T. catappa reveals two types; pouch type and pit+tuft type. Predatory mites are observed on the leaves of only three species including T. catappa. Predatory mites' number per leaf or leaflet proved a few, 0.33~0.40. Insect pests destroying the leaf of tree species are such as aphids, Diaspididae sp., larva of Lepidoptera, and Eriosoma sp.(Pemphlogidae). Ants are co-works with aphids and Diaspididae sp., and supports herbivores. These results indicate that protective mutualisms between tree and predatory mites may be less frequent in woody species of tropical rain forest in Solomon Islands.

• The Journal of the Korea Contents Association
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• v.7 no.8
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• pp.13-20
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• 2007

Decision tree is one of the most useful analysis methods for various data mining functions, including prediction, classification, etc, from massive data. Decision tree grows by splitting nodes, during which the purity increases. It is needed to stop splitting nodes when the purity does not increase effectively or new leaves does not contain meaningful number of records. Pruning is done if a branch does not show certain level of performance. By pruning, the structure of decision tree is changed and it is implied that the previous splitting of the parent node was not effective. It is also implied that the splitting of the ancestor nodes were not effective and the choices of attributes and criteria in splitting them were not successful. It should be noticed that new attributes or criteria might be selected to split such nodes for better tries. In this paper, we suggest a procedure to modify decision tree by Fuzzy theory and splitting as an integrated approach.