• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.145-145
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• 2011

Recently, multi-hole electrode RF capacitively coupled plasma discharge is being used in the deposition of microcrystalline silicon for thin film solar cell to increase the speed of deposition. To make efficient multi-hole electrode RF capacitively coupled plasma discharge, the hole diameter is to be designed concerning the plasma parameters. In past studies, the relationship between plasma parameters such as pressures and gas species, and hole diameter for efficient plasma density enhancement is experimentally shown. In the presentation, the relationship between plasma deriving frequency and hole diameter for efficient multi-hole electrode RF capacitively coupled plasma discharge is shown. In usual capacitively coupled plasma discharge, plasma parameter, such as plasma density, plasma impedence and plasma temperature, change as frequency increases. Because of the change, the optimum hole diameter of the multi-hole electrode RF capacitively coupled plasma for high density plasma is thought to be modified when the plasma deriving frequency changes. To see the frequency effect on the multi-hole RF capacitively coupled plasma is discharged and one of its electrode is changed from a plane electrode to a variety of multi-hole electrodes with different hole diameters. The discharge is derived by RF power source with various frequency and the plasma parameter is measured with RF compensated single Langmuir probe. The shrinkage of the hole diameter for efficient discharge is observed as the plasma deriving frequency increases.

• Journal of Korean Society of Water and Wastewater
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• v.32 no.4
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• pp.349-355
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• 2018

This study interrogated multi-layer heterojunction anodes were interrogated for potential applications to water treatment. The multi-layer anodes with outer layers of $SnO_2/Bi_2O_3$ and/or $TiO_2/Bi_2O_3$ onto $IrO_2/Ta_2O_5$ electrodes were prepared by thermal decomposition and characterized in terms of reactive chlorine species (RCS) generation in 50 mM NaCl solutions. The $IrO_2/Ta_2O_5$ layer on Ti substrate (Anode 1) primarily served as an electron shuttle. The current efficiency (CE) and energy efficiency (EE) for RCS generation were significantly enhanced by the further coating of $SnO_2/Bi_2O_3$ (Anode 2) and $TiO_2/Bi_2O_3$ (Anode 3) layers onto the Anode 1, despite moderate losses in electrical conductivity and active surface area. The CE of the Anode 3 was found to show the highest RCS generation rate, whereas the multi-junction architecture (Anode 4, sequential coating of $IrO_2/Ta_2O_5$, $SnO_2/Bi_2O_3$, and $TiO_2/Bi_2O_3$) showed marginal improvement. The microscopic observations indicated that the outer $TiO_2/Bi_2O_3$ could form a crack-free layer by an incorporation of anatase $TiO_2$ particles, potentially increasing the service life of the anode. The results of this study are expected to broaden the usage of dimensionally stable anodes in water treatment with an enhanced RCS generation and lifetime.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.35C no.2
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• pp.48-55
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• 1998

Structural learning methods of MLP classifiers for a given application using genetic algorithms have been studied. In the methods, however, the search space for an optimal structure is increased exponentially for the physical application of high diemension-multi calss. In this paperwe propose a method of MLP classifiers using species genetic algorithm(SGA), a modified GA. In SGA, total search space is divided into several subspaces according to the number of hidden units. Each of the subdivided spaces is called "species". We eliminate low promising species from the evoluationary process in order to reduce the search space. experimental results show that the proposed method is more efficient than the conventional genetic algorithm methods in the aspect of the misclassification ratio, the learning rate, and the structure.structure.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.531-537
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• 2008

We report an unrecorded species of Corydalis sect. Corydalis (Fumariaceae), C. caudata (Lam.) Pers., that have been found in the central part of Korea. This species is easily recognized by its bearded calyx, upwardly curved spur, and multi-branched characteristics. We named it 'Soo-yeom-hyeon-ho-saek' as korean common name.

• Mycobiology
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• v.50 no.1
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• pp.30-45
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• 2022

During a survey of plant-inhabiting fungi and water niches from Korea, noteworthy fungi were collected; among them, two new species, Paracamarosporium noviaquum sp. nov. and Phyllosticta gwangjuensis sp. nov., are described based on morphology and multi-gene phylogenies. Paracamarosporium noviaquum was characterized by its production of 1-celled and 2-celled conidia, forming conidiomata on only potato dextrose agar medium. Phyllosticta gwangjuensis was characterized by conidia hyaline, ovoid to ellipsoid shape, rounded at both ends, containing numerous guttulae or with a single large central guttule. Additional species were identified as Cosmospora lavitskiae, Monochaetia cameliae, and Roussoella doimaesalongensis, which are reported as new record species from Korea. Detailed descriptions and illustrations of these taxa are provided herein.

• Mycobiology
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• v.51 no.5
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• pp.320-332
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• 2023

Talaromyces is a genus within the phylum Ascomycota (class Eurotiomycetes, order Eurotiales, family Trichocomaceae). Many species in this genus are known to produce diverse secondary metabolites with great potential for agricultural, medical, and pharmaceutical applications. During a survey on fungal diversity in the genus Talaromyces in Korea, six strains were isolated from soil, indoor air, and freshwater environments. Based on morphological, physiological, and multi-locus (ITS, BenA, CaM, and RPB2) phylogenetic analyses, we identified five previously unrecorded species in Korea (T. brevis, T. fusiformis, T. muroii, T. ruber, and T. soli) and a new species (T. echinulatus sp. nov.) belonging to section Talaromyces. Herein, detailed descriptions, illustrations, and phylogenetic tree are provided.

• Journal of Animal Science and Technology
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• v.50 no.1
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• pp.89-98
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• 2008

This experiment was carried out to investigate the combination feeding of β-glucan and multi-species probiotics on growth performance, various lipid concentrations of serum, antibody production and cecal microbial profiles in broiler chicks. A total of six hundred 1-d-old male broiler chicks were divided into five groups, placed into four pens per group(30 birds per pen) and fed one of five non-medicated experimental diets(T1, 0.15% multi-species probiotics; T2, 0.1% β-glucan+0.15% multi-species probiotics; T3, 0.3% multi-species probiotics; T4, 0.1% β-glucan+0.3% probiotics or devoid them as control) for 5 wk. There was no significant difference in feed intake among the groups. The average weight gains and FCR in groups fed diet containing 0.3% probiotics were significantly improved(p<0.05) than control in finisher period(22-35d). The concentration of serum cholesterol ester in groups fed 0.3% probiotics were significantly lowered(p<0.05) as compared to that of the control. Relative weights of liver, spleen, bursa of Fabricius, breast and leg were not influenced by the dietary treatments. The average ND or IB antibody titers in groups fed diets containing β-glucan and probiotics were tended to be increased, but not significantly. The number of cecal lactic acid bacteria was significantly increased(p<0.05) by the dietary β- glucan and probiotics. These results indicated that dietary β-glucan and probiotics exerted a growth- promoting and immune-enhancing effects on broiler chicks. In addition, yeast derived β-glucan, and multi-species probiotics modulated the profiles of cecal microflora, reflecting potential alternative substances to replace antibiotics for feeding broiler.

• The Korean Journal of Ecology
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• v.18 no.4
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• pp.451-462
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• 1995

A comparative study on the minimal areas and the community structures in pine IPinus densiflora) and oak (Quercus mongolica) frests was carried out. Basic tools used in the present study were species diversity and classical ayntaxonomy (Z.-M. School) of the phytocoenosis. Total 120 nest-quadrats in 40 stands situated at the syngeographical region of the Lindero-Quercion mongolicae were investigated. Each stand was classified on the basis of species combination, and species abundance was computed with net contribution degree (NCD). Composition ratio of plant-from and rate of actual species diversity (ASD) to syntaxa were computed for better interpretation of the minimal areas. Four syntaxa were structured: Saso-Quercetum mongolicae, Viola albida-Quercus mongolica community, Carex hummilis-Pinus densiflora community and Juniperus rigida-Pinus densiflora community. Their minimal areas were determined as 305, 196, 169, and 81 ㎡, respectively. Aconsistent regularity between species composition ratio and community structure in the multi-layered plant community was hardly found. The minimal areas increased linearly with increasing rate of ASD, and a phytocoenosis developed by diverse arboreta in the understory and shrub-layer should be investigated with larger sampling sizes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.541-548
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• 2003

Species identification in hydroacoustic survey is one of the key requirements to estimate biomass of organism and to understand the structure of zooplankton community. Feasibility of species identification using two frequencies (38 and 120 kHz) was investigated on the basis of mean volume backscattering strength difference (MVBS). Virtual echogram technique was applied to two frequencies data sets that obtained from surveys in the Antarctic Ocean and Yellow Sea. Virtual echogram method using MVBS revealed the possibility of species identification, which species identification relying on visual scrutiny of single frequency acoustic data resulted in significant errors in biomass estimation. Through noise cancellation using MVBS, much of the acoustic noise caused by acoustic instruments could be removed in new virtual echogram, and the biomass estimation and data quality was improved.

• ALGAE
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• v.35 no.1
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• pp.17-32
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• 2020

Asterochloris is one of the most common genera of lichen phycobionts in Trebouxiophyceae. Asterochloris phycobionts associated with the lichenized fungi Cladonia and Stereocaulon in King George Island (Antarctica) and Morro Chico (Chile), were isolated and then used to establish clonal cultures. To understand the phylogenetic relationships and species diversity of Antarctic Asterochloris species, molecular and morphological data were analyzed by using three microscopy techniques (light, confocal laser and transmission electron) and a multi-locus phylogeny with data from the nuclear-encoded internal transcribed spacer (ITS) rDNA and the actin and plastid-encoded ribulose bisphosphate carboxylase large chain (rbcL) coding genes. Morphological data of three Antarctic strains showed significant species-specific features in chloroplast while molecular data segregated the taxa into distinct three clades as well. Each species had unique molecular signatures that could be found in secondary structures of the ITS1 and ITS2. The species diversity of Antarctic Asterochloris was represented by six taxa, namely, A. glomerata, A. italiana, A. sejongensis, and three new species (A. antarctica, A. pseudoirregularis, A. stereocaulonicola).