• Journal of Power System Engineering
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• v.6 no.1
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• pp.82-87
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• 2002

Not only ferrous but also non-ferrous materials such as aluminum, brass, plastic and woods need cutting operation in recent manufacturing industry. Over the past few years a considerable number of studies have been made on non-ferrous metal cutting. But more study is required to meet various engineering needs. The purpose of this paper is to preform an experiment on the influence of feed-rate adjustment and side rake angle in turning operations from non-ferrous metals. As a result, the surface roughness was reduced when a side-rake angle increases and feed-rate decreases in the case of the plastic, brass, aluminum, and paulownia. Therefore, this papers develop a new type bite that be used to adjust side-rake angle.

• Journal of the Korean Wood Science and Technology
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• v.31 no.6
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• pp.15-21
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• 2003

Image processing technique was adapted for exploring the more convenient ways to investigate the drying characteristics of wood. The acquisition of information about drying characteristics is indispensable for the development or improvement of dry-kiln schedules. A small internal fan type wood dry kiln was combined with image-processing and data-acquisition systems to monitor continuously the formation of checks and moisture reduction during drying. All the images and data were analyzed to improve or estimate the dry-kiln schedules and predict the drying time which would be required to dry green wood to 10% moisture content in internal fan type kiln. Samples of 20 mm- and 50 mm-thick Metasequoia glyptostrobodies, Paulownia coreana Uyeki, Pinus densiflora Sieb. Et Zucc., Platanus occidentalis L., Quercus acutissima and Robinia pseudo-acacia were used to verify the potentiality of this technique.

• Journal of Korean Society of Forest Science
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• v.58 no.1
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• pp.8-16
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• 1982

To study the comparison of aboveground biomass of paulownia coreana Uyeki of 6-year-old, located in Seongju of non-attacked forest and Ulsan of damaged forest by the air pollution were selected. Ten sample trees in Seongju district and seven trees in Ulsan selected taking account of DBH were measured for 16 trees in total within a $10{\times}10m$ experimental plot. The diagram of oven-dry weight distribution of stem, branch and needle for each 1m segment was constructed. The logarithmic regression equations between dry weight of each component and the two-variables, DBH and tree height, combined term were presented. IF the estimations are extended to a hectare area stand, it contains 47.49 tons of aboveground biomass in Seongju district and 19.05 tons of it in Ulsan. The annual net productions were 11.64 tons of above 2.29 kg/kg/yr in Ulsan and the efficiency of leaf to produce stem was 2.99kg/kg/yr in Seongju and 0.83kg/kg/yr in Ulsan.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.269-277
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• 2003

Some species of true bugs have become serious problems in rice, upland crops, and tree fruits. It would be meaningful to understand research status by reviewing articles on those true bugs in Korea. Articles on those bugs published in several scientific Korean journals were reviewed, except articles on true bugs on rice plants; CD Part 1 included classification and morphological studies on eggs and larvae of Piesma spp., on external genitalia of Gonopsis affinis, and on spermathecae of some Podopinae and Asopinae species. $\circled2$ Development and growth analysis of Piesma sp., P. maculata, and 2 species of Coreidae were reviewed in part 2. $\circled3$ In part 3 we reviewed with major pest bug species on soybean, sweet persimmon, yuzu, citrus, chrysanthemum, and Cynanchum wilfordii, and insect fauna in mountain areas. $\circled4$ In part 4, damage levels in soybean, sweet persimmon, yuzu, grapes were reviewed. $\circled5$ ID In part 5 we reviewed seasonal occurrence patterns of Halyomorpha halys, Plautia stali, Riptortus clavatus in sweet persimmon orchards, of some species in soybean fields, of Nysius plebejus on chrysanthemum, and of Tropidothorax cruciger on Cynanchum wilfordii. $\circled6$ Chemical control methods in a sweet persimmon orchard, in grapevine yards, in a soybean field, and in a chrythansemum field were introduced in part 6. Some laboratory bioassay on insecticides against R. clavatus were mentioned, too. $\circled7$ Finally in part 7, researches on transmission by Halyomorpha halys and Cyrtopeltis tenuis of micoplasma-like organism which is a pathogen of paulownia withces' -broom to Catharanthus roseus were reviewed.

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.760-766
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• 2016

This study explored the effects of heating temperature and laminae thicknesses on the time required to heat the center of air-dried Paulownia tomentosa, Pinus sp., Abies sp., and Larix sp. laminae to $56^{\circ}C$, which is a minimum core temperature of wood packaging materials defined by ISPM 15 standard, and maintain for 30 minutes in dry heat treatment schedule. Heating times were different among wood species and were Pinus sp. ${\geq}$ Abies sp. > Paulownia tomentosa > Larix sp. in decreasing order. The differences in heating times of some species were significantly different statistically, but were not different enough in practical terms to warrant heating four species separately. Heating times decreased as heating temperature increased and followed approximately power-function relationship. Also, heating times increased linearly with increasing laminae thickness. These relationships make it possible to calculate intermediate heating times relative to experimentally observed heating times. The results of this study will serve as a guideline for heat sterilization of Chinese laminae species to meet heat treatment requirements for protection against invasive pests.

• Journal of the Korea Furniture Society
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• v.21 no.6
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• pp.486-498
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• 2010

The purpose of this study was to analyze the species of 82 furniture in the late Choseon Dynasty (mainly, 19th century), which are housed in the Seoul Museum of History. Total of 22 species were found. The species shared 43% as hard pine(Diploxylon), 9% as Zelkova serrata Makino, 7% as Paulownia spp., 7% as Tilia spp., 6% as soft pine(Haploxylon), 5% as Ginkgo biloba Linn., 4% as Cedrela sinensis A. Juss., 3% as Diospyros spp., 3% as Abies spp., 2% as Alnus spp., 2% as Picea spp., 1% as bamboo, 1% as Populus spp., 1% as Betula spp., 1% as Juglans spp. The other minor ones were Torreya nucifera Sieb. et Zucc., Pyrus spp., Castanea spp., Ulmus spp. and Kalopanax oictuse (Thunb.) Nakai. Thirty seven furniture (45% in total) was made of single species, 19 (23%) of two species, 16 (20%) of three species and 10(12%) of 4 to 6 species. For frames and panels, hard and strong woods, such as hard pines, Zelkova and Cedrela, were used. For drawer, however, light woods having low shrinkage, such as Paulownia and Tilia, were used. The origin of woods could be specified by the habitats of the species identified. Both Hwanghaedo- and Parkcheon- Chests used basswood (Tilia), which grow in the cold regions, indicating the origin of woods as North Korea.

• Journal of the Korean Wood Science and Technology
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• v.48 no.2
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• pp.217-230
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• 2020

Global warming has increased interest in reducing greenhouse gas emissions. And a policy has effort to reduce energy consumption as a greenhouse gas reduction plan. In Korea, 25% of total energy is consumed in the building sector. In order to reduce energy consumption of buildings, it is possible to expand the utilization of wood as a structural material or thermal insulation materials with low thermal conductivity. It is also reported that when used as an interior finishing material, the energy consumption of the building is reduced by up to 7% by insulation performance. In this study, the heat transfer characteristics and the heat capacity were compared according to the three type of finishing materials(cement, paulownia coreana, medium density fiberboard) normally used as indoor finish materials. Through this study, most of the heat transfer volumes are transferred in the form of radiant heat, and the result was derived from the highest amount of energy and heat transfer in the use of paulownia coreana. When indoor finishing materials are used as wood, it is deemed that energy efficiency inside the building will be improved.

• Korean Journal of Environmental Biology
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• v.30 no.2
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• pp.107-120
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• 2012

This study was carried out to illiminate the diversity of vascular plants by making list of rheophyte and hydorphyte plants at Yugu stream. This study was conducted from Aug., 2009 to Sept. 2010 at 7 points. Based on the voucher specimens, vascular plants from investigated areas were 88 families 229 genera 290 species 3 subspecies 30 varieties 5 forms, totally 328 taxa. Korean endemic plants were 3 species such as Forsythia koreana (Rehder) Nakai (planted) and Paulownia coreana Uyeki (planted), and Weigela subsessilis (Nakai) L.H. Bailey. The rare and endangered plants were designated by Korea Forest Service were 4 taxa, such as Penthorum chinense Pursh, Acorus calamus L., Lilium callosum Siebold & Zucc. and Iris ensata var. spontanea (Makino) Nakai. Floristic special plants were totally 26 taxa, which were grade V of 2 taxa, grade IV of 2 taxa and grade III of 9 taxa. Naturalized plants were 27 taxa, that was 8.3% of whole discovered vascular plants in this area. Even naturalized plants has not influence on the vegetation of Yugu stream. Since village was composed along the stream and the roads and banks were linked, naturalized plants were flowed continuously into this region. So, strategy of the conservation for this region should be designed. Based on flora, 3 types of group were discriminated such as main stream type (4 points), branch stream type (2 points) and reservior type (1 point). Each group has difference in composition of plants.

• Journal of the Korean Wood Science and Technology
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• v.18 no.4
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• pp.65-78
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• 1990

For the purpose of Improving the sounding boards for the conventional GAYAKUM, I was making approximately 202 specimens of radial board, 371 specimens of tangential board by cutting along the grain and the part of stem and 31 specimens of the disjointed traditional GAYAKUM made in Paulownia coreana. And it was conducted to measure specific gravity, dynamic Young's modulus, internal friction, resonant frequency, velosity of sound and width of annual ring by the method of the frexural vibration in a free-free bar in the audio frequency range. And it confirmed the juvenile wood by measuring wood fiber length of specimens. It was also conducted to investigate dynamic properties and moisture absorption by various heat-treatment and to test dynamic Young's modulus and internal friction for the disjointed conventional GAYAKUM. The results obtained were summarized as follow: 1. The Juvenile wood is located within about 7 annual rings from the pith in Paulownia coreana. 2. As increased with the specific gravity, the dynamic Young's modulus had more and more increased, but the internal friction had slightly decreased. 3. I think that radial board would be good for sounding board wood. because radial board is higher than tangential board in dynamic Young's mudulus and internal friction is lower than tangential board. 4. The value of mean dynamic Young's modulus on the conventional GAYAKUM, radial board and tangential board of 604 samples is $0.4283\pm0.037(\times10^{11}dyne/cm^2)$, $0.4316\pm(\times10^{11}dyne/cm^2)$ and $0.4234\pm0.112(\times10^{11}dyne/cm^2)$ respectively. The value of the radial board showed little higher than that of conventional GAYAKUM, but It had a similar tendency between conventional GAYAKUM and tangential board. 5. The annual ring width by four aspect is more narrow in north and west than that of others. 6. The values of specific gravity and dynamic Young's modulus in the mature wood showed higher than those of juvenile wood. 7. As the grain angle in the butt wood more increased to bark from pith, the dynamic Young's modulus were low. Then it was not good for sounding board. 8. It appeared that the heat-treatment for sounding board wood had a more effect to do the treatment of hotiron on surface after heat-treatment during 24 hours in $60^{\circ}C$ temperature. 9. As increased with the temperature, the rate of moisture absorption of heat-treatment wood had decreased. In conclusion, I thought that the sounding board wood for GAYAKUM would had the most effect to do the treatment of hotiron on surface after heat-treatment during 24 hours in $60^{\circ}C$ temperature using the radial board of mature wood.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.447-458
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• 2006

The resource plants at the Manduksan and Mireukbong was listed 550 taxa: 107 families, 339 genera, 481 species, 1 subspecies, 65 varieties and 3 forms. Among 550 taxa listed was confirmed 323 taxa of edible plants (58.7%), 384 taxa of medicinal plants (69.8%), 267 taxa of ornamental plants (48.5%) and 268 taxa of the others (48.7%). Based on the list of the rare plants by the Forest Research Institute, 4 taxa were recorded in the studied areas; Lilium distichum (Preservation priority order: No. 159), Tricyrtis dilatata (No. 97), Aristolochia contorta (No. 151), Prunus yedoensis (No. 110) and based on the list of Korean endemic plants, 11 taxa were recorded; Cephalotaxus koreana, Carex okamotoi, Lilium amabile, Populus tomentiglandulosa, Salix purpurea var. japonica, Pseudostellaria multiflora, Prunus yedoensis, Forsythia koreana, Paulownia coreana, Weigela subsessilis, Aster koraiensis. Specific plant species by floral region were total 30 taxa; Prunus yedoensis in class V, Wistaria floribunda in class IV, 3 taxa (Spiraea salicifolia, Acer palmatum, Asperula lasiantha) in class III, 3 taxa (Potentilla dickinsii, Viola tokubuchiana var. takedana, Caryopteris incana) in class II, 22 taxa (Pinus koraiensis, Hosta capitata, Chloranthus japonicus, Salix glandulosa, Juglans mandshurica, etc.) in class I. This site needs urgent countermeasures, because there have increased many man-made damages like planting exotic plants, picking wild plants and soil compaction induced by human trampling.