• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.684-688
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• 2001

The structural, piezoelectric and dynamic range characteristics of modified PbTi $O_3$ceramics were investigated as a function of Mn $O_2$addition. With the increase of Mn $O_2$addition, Curie temperature was decreased. As the increase of Mn $O_2$addition, mechanical quality factor ( $Q_{mt3}$) in the third over tone thickness mode was increased. Dynamic range in the third over tone thickness mode was also increased with the increase of Mn $O_2$addition. The composition ceramics added to 0.075wt% Mn $O_2$showed the best properties for SMD type resonator using third over tone thickness vibration in terms of high Curie temperature more than 31$0^{\circ}C$ and dynamic range of 49.38dB.B.

• Korean Journal of Poultry Science
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• v.39 no.4
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• pp.311-315
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• 2012

The increasing demand for Korean native chicken meat indicates that the discovery of haplotypes is very important from both economic and conservation points of view. In this study, mtDNA D-loop sequences from two crossbred Korean native chicken populations of 138 individuals were investigated. Twenty six nucleotide substitutions were identified from sequence analysis and were classified into 12 haplotypes. The haplotype H_8 represents 73.47% of Woorimatdag (chicken population) sequences, which were identified in all five Woorimatdag chicken populations investigated. The H_7 haplotype (Dhap1) for D population covers 45% sequences, which indicate maternal inheritance from black Korean native chicken. On the other hand, Chap3 and Chap4 for C population are specific haplotypes, as H_5 and H_2, respectively. Based on the network profiles, six SNPs (C199T, A239G, G242A, A291G, T330C and C391A) of the D-loop region are effective markers for discrimination between Woorimatdag and Hanhyup chicken populations. Also, the phylogenetic analyses of Woorimatdag and Hanhyup chicken populations were used to identify the genetic relationships among the haplotypes. The results presented here can be used for developing molecular markers to discriminate between two commercial Korean native chickens.

• Journal of Korean Society of Forest Science
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• v.82 no.2
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• pp.188-194
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• 1993

A natural Quercus variabilis forest and a Populus alba${\times}$P. glandulosa plantation in Mt. Mohu area were studied to investigate aboveground biomass and net production. A $20m{\times}30m$ quadrat was set up in each stand, and 10 sample trees each of Quercus variabilis and Populus alba ${\times}$ P. glandulosa were cut for dimension analysis. There was little difference in accuracy among three biomass regression models of logWt=A+BlogD, $logWt=A+BlogD^2H$, and logWt=A+BlogD+ClogH, where Wt. D, and H were dry weight, DBH, and height, respectively. Aboveground total biomass of Quercus variabilis stand was 31,275kg/ha, and that of Populus alba ${\times}$ P. glandulosa was 55,581kg/ha. In both of Quercus variabilis stand and Populus alba ${\times}$ P. glandulosa stand, the proportion of each tree component to abovegound total biomass was high in order of stem wood, branches, stem bark, and leaves. Quercus variabilis stand was higher in the proportion of stem bark, branches and leaves than Populus alba ${\times}$ P. glandulosa stand, while the former was lower in that of stem wood than the latter. Aboveground total net production of Quercus variabilis stand was 4,267kg/ha/yr., and that of Populus alba ${\times}$ P. glandulosa stand was 3,903kg/ha/yr. The proportion of each tree component to aboveground total net production of Quercus variabilis stand was high in order of leaves, stem wood, branches, and stem bark. That of Populus alba ${\times}$ P. glandulosa stand was high in order of stem wood, leaves, branches, and stem bark. Net assimilation rate and efficiency of leaf to produce stem of Quercus variabilis stand were 2.121 and 0.840, respectively. Those of Populus alba ${\times}$ P. glandulosa stand were 3.376 and 2.085, respectively. Though Populus alba${\times}$P. glandulosa stand was lower in aboveground total net production than Quercus variabilis stand, the former was higher in aboveground total biomass than the latter. The reason was that Populus alba${\times}$P. glandulosa stand was higher in net production of stem wood of accumulation organs than Quercus variablis stand.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.3
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• pp.168-182
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• 2014

Several Sungsi Gardens were built up in Old West Village during the period of the Joseon Dynasty. Most of them were painted as True-View landscape painting. This study aims at examining original locations of representative gardens of the Old West Village by empirical investigation of related True-View landscape paintings. It seeks to demonstrate the garden landscape in True-View landscape painting by utilizing ArcGIS, 3D topographic modeling to observe geographical locations and landscape more realistically. After forming 3D topographic modeling of estimated locations of the gardens, location of objects at composition of 3D modeling similar to True-View landscape painting was found by shifting viewpoints. And by overlapping the cadastral map on the modeling, we could verify the current lot number of the garden sites. The interpretation of processes and results are as follows. In the early stage, Chungpunggye garden was built at the very end of Mt. InWang valley. The site is hidden from the outside, and appeared as 'Enclosed Landscape'. In the middle stage, Chunghuigak garden was built between Okryu-dong valley and the surrounding ridge. It appeared as 'Semi-Opened Landscape'. In the late stage, Seowon garden was built at the highest level of the ridge among the research areas. It appeared as 'Prospective Landscape'. In the last period, Songsukwon garden, was built at a point of contact of the ridge end and surrounding residential area. So it appeared as 'Opened Landscape' to the town. In other words, the location, landscape and social function of the gardens in Old West Village had been gradually opened in Joseon Dynasty.

• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.13-23
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• 2008

The triaxial compression tests and consolidation tests using NaCl solution and leachates as substitute pore (or saturated) water in samples were carried out to find out the behavior characteristics of strength, deformation and permeability coefficient of contaminated clay. Also, the chemical property analysis on the clay samples using scanning electron microscope and energy dispersive x-ray spectrometer were involved. The magnitudes of composition ratio were shown in the order of O, C, Si, Al, and Fe as a result of chemical composition analysis for clay samples. Besides, as the results of triaxial compression tests and consolidation tests, the shear strength, compression and permeability properties were increased with increasing in the concentration of contaminant (NaCl). It may be considered that these circumstances be caused by the changes of soil structure to flocculent structure due to the decrease in the thickness of diffuse double layer with increasing in the concentration of electrolyte. MT3D model was also using to grasp the procedures that the groundwater may be contaminated by the leachates permeated through the clay liner. The results of contaminant transport analysis showed a tendency that the predicted concentration of groundwater was higher with increasing in the initial concentration of $Cl^-$ ion and increased as a nonlinear curves with time. The transportation distance calculated by the use of regression equation between the distance from contaminant source and the concentration of $Cl^-$ ion was increased with increasing the initial concentration.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.48-62
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• 2016

This study was conducted to classify forest vegetation structure and stand feature of Mt. Deogyusan National Park from Hyangjeukbong to Jungbong, 48 plots were surveyed. The type classification of the vegetation structure was performed with Z-M phytosociological method. As a result, Quercus mongolica community group was classified into the Picea jezoensis community, Carpinus cordata community and Tilia amurensis community in community unit. P. jezoensis community was subdivided into Deutzia glabrata group and Viburnum opulus var. calvescens group in group unit. D. glabrata group was subdivided into Acer mandshuricum subgroup and Ribes mandshuricum subgroup and V. opulus var. calvescens group was subdivided into Hemerocallis dumortieri subgroup and Prunus padus subgroup in subgroup unit. In the result of estimating the importance value, it constituted Q. mongolica (23.9%), Abies koreana (14.7%), Taxus cuspidata (10.2%), P. jezoensis (8.2%) and Betula ermanii (7.4%) in tree layer. It constituted Acer komarovii (18.6%), Acer pseudosieboldianum (18.4%) and Q. mongolica (8.9%) in subtree layer. It constituted Rhododendron schlippenbachii (20.7%), A. pseudosieboldianum (17.4%) and Symplocos chinensis (8.5%) in shrub layer. Indicator species analysis of vegetation unit 1 was consisted of Hydrangea serrata, Fraxinus mandshurica and D. glabrata that species prefer moist valley in subalpine or rocks. In the results of analyzing the species diversity, vegetation unit 1, 4 and 5 represented that there were different and complex local distributions. As in the similarity between the vegetation units, the vegetation units 1, 2, 3 and 4 represented high with 0.5 or above. It represented that there wasn't no differences on composition species in vegetation units.

• The Korean Journal of Zoology
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• v.21 no.1
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• pp.29-39
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• 1978

The authors observed the ultrastructure of the mucous glandular epithelial cells in the amphibian skin by mean of electron microscope. The specimens from the experimental animals were fixed in 2.5% glutaraldehyde-oaraformaldehyde fixative in phosphate buffer at pH 7.2 prior to fixation in 1% osmium tetroxide, dehydrated in graded ethanol and acetone, embedded in Epon 812 mixture, and sectioned with Sorvall MT-2 ultramicrotome. The ultrasections were contrasted with uranyl acetate and lead citrate and observed with a JEOL-100B electron microscope. The results were as follows: 1. The cutaneous mucous glands in amphibia consisted of the glandular epithelial and the myoepithelial cells. 2. Several different cells in ultrastructure were observed in the mucous glandular epithelium of the adult amphibian skin. a. The dark and the light cells were observed in Hynobius leechi. b. The mitochondria-rich and the round secretory granule-containing cells were observed in Bombina orientalis. c. The round secretory granule-containing and the foam-like granule mass-containing cells were observed in Kaloula tornieri. d. The cutaneous mucous gland of Rana nigromaculata were divided into two types: A and B-type glands. In the A-type mucous gland, the mitochondria-rich and the round secretory granule-containing cells and in the B-type mucous gland, the mitochondria-rich, the secretory granule-containing and the ER-rich cells were observed. 3. Based upon the above findings, the authors infer that the mucous granular epithelium of the amphibian skin consists of the mitochondria-rich undifferentiated, the secetory granule-containing and mature, and the ER-rich evacuated cells.

• Journal of the Korean Society of Safety
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• v.32 no.3
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• pp.112-116
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• 2017

This study applied risk indexes to the disaster flow event occurred at Mt. Umyeon region in 2011. A 2D hydrodynamic model was employed to calculate flow characteristics, and the model was validated against two dam break flow problems conducted by Bellos and EU CADAM project. The model performance was shown to be satisfactory. In order to determine which index is more appropriate to assess the vulnerability of debris flow, 3 risk indexes (FII, FHR and VDI) were considered. It was found that VDI, which determines the risk level only by the velocity factor, consistently predicted the risk level corresponding to 6 because the velocity range was widely organized. However, in the case of FII and FHR, the risk was reasonably quantified due to combined consideration of significant factors of flow velocity and debris thickness. Therefore, FII and FHR are expected to be more accurate than VDI. However, two indexes still need to be improved to include major factors such as debris density or material properties.

• Journal of Soil and Groundwater Environment
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• v.24 no.3
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• pp.13-23
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• 2019

The purpose of this study is to suggest conceptual models based on finite numerical method that can be used to assess contaminant transport through subsurface and estimate exposed concentration at contaminated site. This study tested various assumptions of the numerical models for contaminant transport in unsaturated and saturated zones to simulate the pathways to the human exposal point. For this purpose, models for seven possible scenarios of contaminant transport were simulated using the numerical code MODFLOW and MT3D. The simulation results that showed different peak concentrations and travel times were compared. In conclusion, the potential utility of the numerical models in the site specific risk analysis suggested as well as future research ramifications.

• Journal of Forest and Environmental Science
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• v.19 no.1
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• pp.69-84
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• 2003

The study was carried out to investigate the flora and community classfication of forest vegetation in Mt. Yumyeong from March. 2002 to October. 2003. As a result of that. the vascular plants were 98 families, 331 genera, 570 species, 1 subspecies, 81 varieties, 4 formae, 2 hybrid, 658 taxa in all. Korean endemic plants were 10 families, 14 genera, 13 species, 2 variaties, 1 hybrid, 16 taxa in all; rare and endangered plants were 9 families, 10 genera, 11 species, 11 taxa in all: naturalized plants were 12 families, 22 genera, 28 species, 28 taxa in all. The forest vegetation was classified into 1 order, 1 alliance, 6 communities; Rhododendro - Quercetalia mongolicae (Kim, 1990) Lindero - Quercion mongolicae (Kim, 1990) A. Carex humiljs var. nana - Pinus densiflora Community B. Oplismenus undulatifoljus - Pinus koraiensis Community C. Fraxinius rhynchophylla - Quercus mongolica Community D. Cornus controversa - Quercus mongolica Community E. Quercus variabilis - Quercus mongolica Commnuty F. Lespedeza bicolor - Quercus mongolica Community.