• Journal of Korean Society of Forest Science
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• v.106 no.2
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• pp.150-168
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• 2017

This study was carried out to compare stand structure in Bihwajin basin Samcheok-si, Gangwon-do, Korea for ten years between 2003 and 2014, in which occurred the east coastal forest fire in 2000. Data were collected from 32 quadrates that followed by the analysis of vegetation classification according to plant sociology, importance value by Mclntosh and Curtise, species diversity and similarity index. In the result of vegetation classification, the vegetation unit decreased from 7 units to 4 units, and the number of species groups changed from 11 to 7. As a result of importance value (IV) changes, IV of Quercus mongolica, Q. serrata and Q. variabilis was increased by 6.8%, 5.2% and 2.9% in the order, respectively. However, that of Pinus densiflora was decreased by 2.8%. That of major planted species such as Castanea crenata, Chionanthus retusa, Prunus armeniaca var. ansu, Acer triflorum and Koelreuteria paniculata was reduced. As a result of species diversity, it was increased from 0.252 to 0.287 in tree layer, from 0.252 to 0.434 in subtree layer, and from 1.293 to 1.333 in shrub layer. But that in herb layer was decreased from 1.745 to 1.646. As a result of similarity index, it was 0.78, 0.65, 0.72 and 0.55 by layers that showed most difference in herb stratum. Considering the results, this study would be applied to the ecosystem diagnose and management of forest fire damaged area similar to the investigated area.

• Korean Journal of Environment and Ecology
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• v.29 no.3
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• pp.309-332
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• 2015

To investigate the distribution of vascular plants growing in Mt. Taebaeksan, a survey was conducted from April, 2014 to October, 2014. The flora of Mt. Taebaeksan was classified as a total of 406 taxa comprising of 79 families, 238 genus, 352 species, 4 subspecies, 43 varieties and 7 forma. Among them, 8 taxa were identified as endemic plants in Korea including Salix koriyanagi Kimura, Aconitum pseudolaeve Nakai, Anemone koraiensis Nakai, etc. 16 taxa of Korean rare plants species were identified including 4 taxa in the degree of VU (Asplenium spinulosum (Maxim.) Milde, etc.) and 12 taxa in the degree of LC (Clematis koreana Kom., Eranthis stellata Maxim., Aristolochia manshuriensis Kom., etc.) The floristic special plants were a total of 107 taxa which consist of 3 taxa in degree V(Polypodium virginianum L., etc.), 14 taxa in degree IV(Asplenium otophorum (Miq.) Koidz., etc.), 31 taxa in degree III (Abies nephrolepis (Trautv.) Maxim., etc.), 32 taxa in degree II(Lycopodium chinense H.Christ, etc.) and 27 taxa in degree I(Dryopteris crassirhizoma Nakai, etc.). For the naturalized plants, 16 taxa were identified (Fallopia dumetorum (L.) Holub, Rumex crispus L., Cerastium glomeratum Thuill). Also, the percentage of urbanization index was 5 %, and the naturalized plant index was 3.9 % respectively.

• Korean Journal of Plant Resources
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• v.33 no.2
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• pp.138-152
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• 2020

We investigated the Riparian floras in Hwangjicheon stream from April 2017 to October 2019. 223 taxa (i.e. 203 species, 2 subspecies,18 varieties from 158 genera of 65 families) of the vasclur plants were found in Hwangjicheon stream. Among 223 taxa, we found 4 endemic species, and However, rare and endangered plants were not found in Hwangjicheon stream. The number of floristic regional indicator plants was 22 (i.e. 3 species of IV degree, 4 taxa of III degree, 7 taxa of II degree, and 8 taxa of I degree). In addition, 28 naturalized plants were identified, and the percentage of Naturalized Index (NI) and Urbanization Index (UI) were 12.5%, and 8.7%, respectively. Vascular plant usability and reclassification result is Edible 166 species (74.4%), Medicinal 187 species (83.8%), Flavor 9 species (4.0%), Industrial 99 species (44.3%), Ornamental 106 species (47.5%), Restoration 84 species (37.6%), Compost 112 species (50.2%), Unknown 5 species (2.2%). We hope that our results provide reference data to set up strategy of conservation of biodiversity in the Hwangjicheon stream and Taebaek-si areas.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.426-431
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• 2013

Nanosized $TiO_2$ particles were prepared from titanium (IV) sulfate solution using base solutions at low reaction temperature ($95^{\circ}C$) and atmospheric pressure by hydrothermal precipitation method without calcination. The effects of preparation conditions, such as kind of base solutions (NaOH, $NH_4OH$, Monoethanolamine, Diethanolamine, Triethanolamine) and surfactants (CTAB, Span 20, SDBS), concentration of surfactants, temperature and pH, on the physical properties of $TiO_2$ particles have been investigated by XRD, SEM and Zeta-potential meter. Absorption area was also investigated by DRS in order to confirm the photocatalytic activity of the nanosized $TiO_2$ particles. It was turned out that, among base solutions, NaOH provides the smallest $TiO_2$ particles with excellent crystallinity. And cationic surfactant (CTAB) prepared smaller $TiO_2$ particles than any other surfactants. When CTAB is added in the concentration ratio of $Ti(SO_4)_2$:CTAB=10:1, $TiO_2$ particles with particle diameter of 5.8 nm were prepared. This is approximately 1/10 of that prepared without CTAB.

• Korean Journal of Plant Resources
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• v.35 no.1
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• pp.44-70
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• 2022

This study was carried out to investigate the distribution and characteristics of vascular plants resources in Palbongsan Mt., to compare with previous study and to provide basic information for management and preservation of vegetation. We surveyed eleven times by dividing routes from April of 2018 to May of 2021. The result of this survey revealed a total of 450 taxa, consisting of 101 families, 298 genera, 405 species, 11 subspecies, 28 varieties and 6 forms. Among them, the Korean endemic plants were 8 taxa and the rare plants were 4 taxa. The floristic target species were 30 taxa including 2 taxa of grade IV, 6 taxa of grade III, 7 taxa of grade II, and 15 taxa of grade I. The naturalized plants were 39 taxa, the percent of naturalized plant species was calculated to be 8.67% and urbanization index was 12.15%. Ecosystem disturbance wild plants were 5 taxa. It is considered continuous monitoring and periodic vegetation management of the distribution status of naturalized plants and ecosystem disturbance wild plants found at the edges of forests, fields and forests would be carried out.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.42-50
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• 2021

The purpose of this study was to identify and analyze the communication behavior styles of hemodialysis nurses based on the structured Q-methodology. The Q-population was formulated based on literature reviews and in-depth interviews with 10 hemodialysis nurses who were working in hospitals in Seoul and Anyang-si, Gyeonggi Province. A total of 50 Q-samples, which were believed to best represent the communication behavior styles of hemodialysis nurses, were selected from the Q-population by the author and a professor majoring in nursing. 30 P-samples were selected from hemodialysis nurses who were working in primary, secondary, and tertiary hospitals in Seoul. Q-sorting was performed by P-samples and data was analyzed through the pc-QUANL program. The results suggested that there are four types of communication behavior styles of hemodialysis nurses, namely: "type I: listening and speaking courteously with an active mind", "type II: listening and speaking courteously with a receptive mind", "type III: advising with an explanation" and "type IV: super-reasonable with a defensive mind". It is expected that the analytical results described here may provide basic information that can be used to develop educational material for hemodialysis nurses.

• Korean Journal of Plant Resources
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• v.27 no.5
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• pp.501-517
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• 2014

This study was carried out to elucidate the distribution of vascular plants and their usefulness of Mt. Myeonsan (1,245 m) and Myobong (1,168 m) in Gangwon-do and Gyeongsangbuk-do. The vascular plants that were collected 15 times from April 2012 to October 2013 consisted a total of 551 taxa; 96 families, 314 genera, 489 species, 3 subspecies, 54 varieties and 6 forms. The plants that are specially noteworthy are 17 taxa of Korean endemic plants, 2 taxa of Critical Endangered Species (CR), 3 taxa of Endangered Species (EN) and 12 taxa of Vulnerable Species (VU) in rare plants as categorized by the Korean Forest Service. Furthermore, V, IV, III degrees of floristic regional indicator plants as categorized by the Korean Ministry of Environment included 2 taxa, 22 taxa and 26 taxa, respectively. Among them, edible, pasture, medicinal, ornamental, timber, dye, fiber, industrial and unknown usefulness plants included 215 taxa, 184 taxa, 163 taxa, 59 taxa, 17 taxa, 6 taxa, 5 taxa, 5 taxa and 138 taxa, respectively. In addition, 25 taxa of naturalized plants were observed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.4
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• pp.23-40
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• 2012

The vascular plants of major sites in Changwon-si were listed 456 taxa (9.3% of all 4,881 taxa of vascular plants); 112 families, 293 genera, 371 species, 2 subspecies, 66 varieties and 17 forms. The vascular plants of Changwon-cheon were listed 133 taxa, Junam reservoir were listed 90 taxa, Seongju-sa were listed 293 taxa, and Yungji park were listed 164 taxa. Divided into 456 taxa; woody plants were 160 taxa (35.1%) and herbaceous plants were 296 taxa (64.9%). Furthermore, therophytes (Th) were 111 taxa (24.3%), hemicryptophytes (H) were 75 taxa (16.4%), megaphanerophytes (MM) were 63 taxa (13.8%) showed high proportional ratio in life form. Based on the list of rare plants by the Korea Forest Service and Korea National Arboretum, 10 taxa (1.8% of all 571 taxa of rare plants); Aristolochia contorta (LC), Euryale ferox (VU), Melothrua japonica (LC), Utricularia pilosa (CR), Hydrocharis dubia (LC), Carex idzuroei (DD), Acorus calamus var. angustatus (LC), etc. Based on the list of endemic plants by the Korea National Arboretum, 10 taxa (3.0% of all 328 taxa of endemic plants); Salix pseudolasiogyne, Philadelphus incanus, Indigofera koreana, Lespedeza ${\times}$ maritima, Stewartia pseudocamellia, Weigela subsessilis, Carex okamotoi, etc. Based on the list of specific plants by floral region were total 43 taxa (4.0% of all 1,071 taxa of specific plants); 4 taxa (Euryale ferox, Hydrocharis dubia, Carex idzuroei, etc.) in class IV, 9 taxa (Ilex crenata, Acer palmatum, Stewartia pseudocamellia, Melothria japonica, Fatsia japonica, etc.) in class III, 3 taxa (Caltha palustris var. membranacea, Nymphoides indica, etc.) in class II, 26 taxa (Cyrtomium fortunei, Chloranthus japonicus, Quercus variabilis, Ulmus parvifolia, Aphananthe aspera, etc.) in class I. Based on the list of naturalized plants, 48 taxa (Rumex crispus, Chenopodium album var. album, Amaranthus patulus, Phytolacca american, Brassica juncea var. integrifolia, Potentilla paradoxa, Robinia pseudoacacia, Euphorbia maculata, Oenothera odorata, Cuscuta pentagona, Veronica persica, Plantago lanceolata, Diodia teres, Helianthus tuberosus, Dactylis glomerata, etc.), naturalization rate was 10.5% of all 456 taxa of vascular plants and urbanization index was 15.0% of all 321 taxa of naturalized plants. Ecosystem disturbing wild plants were 3 taxa (Rumex acetocella, Solanum carolinense, Ambrosia artemisiifolia).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.521-526
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• 2017

In the GTA welding process of Al 7075 alloy using different types of filler metals, the tensile test and micro-hardness test were conducted to evaluate the mechanical characteristics. Also, the radiographic test result showed that the weld met the criterion of level 1 in accordance with KS D 0242 for verifying the welding integrity and there were no welding defects. The tensile test result obtained using Al 7075 as a filler metal showed that the material was fractured in the weld zone. The tensile strengths of the materials using Al 7075 and ER 4043 as the filler metal were about 240MPa and 253MPa, their yield strengths were about 132MPa and 120MPa and their elongation percentages were 6.6% and 13%, respectively. The micro-hardness value of the deposited metal zone when using Al 7075 as the filler metal was Hv 132. However, the micro-hardness of the material using ER4043 as the filler metal was about 24% lower than that using Al 7075. When the chemical composition of the filler metal is the same as that of the material itself, fracture can occur in the deposited metal zone. Therefore, it is not desirable to use the same material as the filler metal for the welding of Al 7075 alloy. Moreover, the use of Al-Si based ER 4043 as a filler metal is more desirable than using the same material as a filler metal for welding Al 7075.

• Korean Journal of Environment and Ecology
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• v.21 no.6
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• pp.468-486
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• 2007

It was found that vascular plants distributed at Yeondo islet were composed of 107 families, 312 genera, 408 species, 2 subspecies, 51 varieties and 5 forms, totaling 466 taxa. 39 species including Myrica rubra among the 466 taxa were evergreen broad-leaved tree, and as for flora region science-based specially designated plants by the Ministry of Environment, it was surveyed that 85 taxa(46 families, 70 genera, 80 species and 5 varieties) were distributed by identifying 53 taxa in grade one, 1 taxa in grade two, 26 taxa in grade three, 3 taxa in grade four, and Milletia japonica and Arisaema negishii in grade five. In the naturalized plants, a total of 42 taxa(13 families, 37 genera, 40 species and 2 varieties) were surveyed to be distributed and the ratio of their naturalization and Urbanization Index was analyzed to be 9.01% and 14.63%, respectively. Life form spectra bore a type of H-Dl-R5-e. Vegetation of Yeondo islet are classified as Pinus thunbergii community and Castanopsis sieboldii community, and Miscanthus sinesis var. purpurascens community spread on an gently slanted mountain side.