• 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.

• 한국정보교육학회:학술대회논문집
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• 2021.08a
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• pp.269-274
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• 2021

With the development of artificial intelligence, society is moving to a different world. As a result, amid growing interest in artificial intelligence education, research on how to teach artificial intelligence is also being conducted more actively in Korea. However, a lot of research is being conducted around the upper grades of elementary school, and curriculum and programs for the lower grades are insufficient. Therefore, this study developed an artificial intelligence program for lower grades. Among them, it was developed focusing on artificial intelligence image recognition. It compares image recognition methods of people, animals, and computers, identifies the characteristics of fallen leaves, and helps them understand the image recognition process of artificial intelligence by classifying them according to the characteristics of fallen leaves. I hope this program will help elementary school students understand the image recognition principle of artificial intelligence in the future.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.17-22
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• 1988

Inhibitory effect of L. leptolepis fallen leaf extracts on the germination of Pinus densiflora, ${\times}$ Pinus rigitaeda, Pinus rigida, Pinus thunbergii and Larix leptolepis was investigated. Germination of those seeds in culture room and in pot at field showed the highly significant inhibitory effects by the aqueous extracts from L. leptolepis fallen leaves. Among them L. leptolepis was the most severely inhibited by the aqueous extracts used. To identify allelopathic substances, thin-layer chromatography was employed. Gallic, ferulic, t-cinnamic and vanillic acids were identified from fallen leaves of L. leptolepis. From the results, it is assumed that autotoxicity of L. leptolepis may act as inhibitory factors on germination of the species in natural stands.

• Journal of Sericultural and Entomological Science
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• v.48 no.2
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• pp.41-45
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• 2006

Mulberry leaves contain many natural components and are considerable resource for natural antiokidants. The antioxidant effect of 'Cheongilppong' collected from Chuncheon, Suwon and Wanju regions were investigated with minilum L-100 device and ARAW-KIT (anti-radical ability of water-soluble substance), in comparison to the ascorbic acid. The measurement parts were mulberry leaves collected from different areas and some kinds of mulberry branches. We obtained that even if samples were same variety, antioxidant capacity of those showed different results according to collected regions. Also, antioxidant effect of mulberry leaves were higher than that of branches. The order of antioxidant effect in Spring was Chuncheon > Suwon > Wanju. The antioxidant effect of mulberry leaves collected from Chuncheon, Suwon and Wanju regions of just before the coloration stage with anthocyanin in fruits were 3627.5 nmol, 2620.0 nmol 1360.7 nmol (ascorbic acid equivalents), respectively. In Autumn, the antioxidant effect and hardness quality of mulberry leaves were increased gradually until just before fallen leaves stage. Therefore, we concluded that being the most suitable period for collecting mulberry leaves as a antiokidant resource is from the latter part of May to the first ten days of June.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.71-77
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• 2015

Much attention has been focused on the activity of the natural antioxidants present in fruits and vegetables, because potentially these components may reduce the level of oxidative stress. Especially, mulberry leaves containing many natural components are considerable resource for natural antioxidants. The antioxidant capacity of mulberry leaves was investigated with minilum L-100 device and ARAW-KIT (anti-radical ability of water-soluble substance), in comparison to the ascorbic acid. The antioxidant capacity of 16 varieties was 3303.4 nmol at opening stage of five leaves in spring. The highest stage of antioxidant capacity (3708.0 nmol) and yield rate was just before the coloration stage with anthocyanin in fruits, whereas the lowest stage was middle of June (2231.6 nmol) and about two months growing stage after summer pruning (2064.6 nmol). But after summer pruning, the antioxidant capacity of mulberry leaves increased gradually until just before fallen leaves stage. Even if samples were same variety, antioxidant effect of those showed different results according to collected regions. Also, antioxidant effect of mulberry leaves were higher than that of branches. The antioxidant capacity of yield-type mulberry leaves and fruits (Morus alba L., M. bombycis Koidz, and M. Lhou (Ser.) Koidz) collected from In-je, Won-ju and Yang-yang regions, Kang-won province, Korea, was investigated. The results indicated that total antioxidant capacity of yield-type mulberry leaves was 2711.2 nmol. In the antioxidant capacity analysis of Jeollabuk-Do genetic resources, autumn's mulberry leaves showed higher antioxidant capacity than that of spring's it. To investigate the effect of tea on antioxidative capacity, five kinds of tea(coffee mix, green tea added brown rice, mulberry leaf tea, Polygonatum odoratum tea and black tea added lemon) were selected and analyzed. Their's anti-oxidative capacity were 2,531.01 nmol, 1,867.42 nmol, 1,053.72 nmol, 292.71 nmol and 188.91 nmol, respectively. The antioxidative capacity of drinking water soaked with mulberry leaf showed 891.96 nmol.

• The Korean Journal of Ecology
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• v.23 no.3
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• pp.267-271
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• 2000

Many myxomycetes were collected at Mt. Moak, Mt. Jiri, Mt. Manduck, Mt. Pangtae from June, 1996 to August, 1997. They were identified. According to the results Badhamia macrocrapa, Craterium leucocephalum, Cribraria splenden, Didymium melanospermum, D. minus, Perichaena chrysosperma, Physarum melleum, P. viride and Perichaena chrysosperma were unrecorded species in Korea. They were designed Korean common name by author. Also they will be added to list of Korean myxomycetes. Characterisctics of them were habitated on rotten wood and fallen leaves.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.110-110
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• 2010

Suspension insulator have made use of porcelain insulator mainly, but polymer insulator is using recently. Polymer suspension insulator have advantage that it is light than porcelain insulator. The ageing performance is excellent and it is possible for mass production. There is high possibility of mountain fire because a lot of potential inflammables such as fallen leaves are stacked on the ground Therefore surface aging of polymer insulator most of the overhead transmission lines in Korea are operated on the mountain need analysis of transmission line into forest fire. surface aging property is analyzed by SEM, EDX, XPS, FTIR, DSC in this paper.

• Korean Journal of Plant Resources
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• v.16 no.3
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• pp.245-250
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• 2003

Many myxomycetes were collected at Pyunsan penisula national park, Mt.Moak, Mt.Minjuji, Mt.Manrae, Wanju, Mt.Unjang from July, 1996 to August, 2000. They were identified. According to the results, Amaurochaete tubulina, Cribraria microcarpa, Cribraria splendens, Diachea leucopodia, Entreridium lycoperdon, Stemonitis flavogenita and Stemonitis fusca were unrecorded species in Korea. Characterisctics of them were habitated on rotten wood and fallen leaves. They were designed Korean common names by author.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.425-428
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• 2004

65% of the Korean peninsula is composed of mountainous area, 97% of which is composed of forest. Therefore, there is high possibility of mountain fire because a lot of potential inflammables such as fallen leaves are stacked on the ground. Moreover, most of the overhead transmission lines in Korea are operated on the mountain. However, there has been very little study for the effect of mountain fire on polymeric insulator for transmission line, though the study is significantly required Therefore, in this study the authors observed the deformation of the housing of the insulator under fire with respect to the ignition time, using artificial ignition testing equipment, and investigated electrical and mechanical characteristics of the insulator by dry withstand voltage test, impulse flashover test and tensile load test.

• The Korean Journal of Soil Zoology
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• v.4 no.2
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• pp.61-68
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• 1999

This study reports evolution of spiders which were introduced 400 million years ago in ecological and evolutional aspects. First ecological aspects: underwater life, life of fallen leaves, the crevice of soil, underground life, life in cavern, wandering life in the surface of the earth and threading life in the air. Second evolutional aspects : a kind of the arachnids and morphological change.