• Journal of the Korean Society for Heat Treatment
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• v.23 no.3
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• pp.150-155
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• 2010

Generally, plasma nitriding process has composed with a nitriding layer within glow discharge region occurred by energy exchange. The dissociations of nitrogen molecules are very difficult to make neutral atoms or ionic nitrogen species via glow discharge area. However, the captured electrons in which a double-folded screen with same potential cathode can stimulate and come out some single atoms or activated ionic species. It was showed an important thing that is called "hat is a dominant component in this nitriding process?" in plasma nitriding process and it can take an effective species for without compound layer. During a plasma nitriding process, it was able to estimate with analyzing and identification by optical emission spectroscopy (OES) study. And then we can make comparative studies on the nitrogen transfer with plasma nitriding and ATONA process using plasma diagnosis and metallurgical observation. From these observations, we can understand role of active species of nitrogen, like N, $N^+$, ${N_2}^+$, ${N_2}^*$ and $NH_x$-radical, in bulk plasma of each process. And the same time, during DC plasma nitriding and other processes, the species of FeN atom or any ionic nitride species were not detected by OES analyzing.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.5
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• pp.29-35
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• 1999

Inductively coupled plsama etching of platinum thin film was studied using $O_2$ addition to $Cl_2$/Ar gas plasma. In this study, Pt etching mechanism was investigated with Ar/$Cl_2$ /$O_2$ gas plasma by using XPS and QMS. Ion current density was measured with Ar/$Cl_2$ /$O_2$ gas plasma by using single Langmuir probe. It was confirmed by using QMS and single Langmuir probe that Cl and Ar species rapidly decreased and ion current density was also decreased with increasing $O_2$ gas ratios. These results implied that the decrease of Pt etch rate is due to the decrease of reactive species ans ion current density with increasing $O_2$ gas mixing ratios. A maximum etch rate of 150nm/min and the oxide selectivity of 2.5 were obtained at Ar/$Cl_2$ /$O_2$ flow rate of 50 seem, RF power of 600 W, dc bias voltage of 125 V, and the total pressure of 10 mTorr.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.4
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• pp.158-170
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• 2016

We investigated the occurrence of the dinoflagellate genus Alexandrium in the nineteen Korean coastal sites from July to October 2013. Alexandrium-like planktonic cells were microscopically observed only in four out of the 19 sampling sites. From the samples containing Alexandrium-like cells 22 clonal cultures of Alexandrium species were established by single cell or single chain isolation method. Taxonomic identity of the 4 different strains ascertained by the robust analyses of morphological and molecular genetic characteristics were confirmed to be A. catenella, A. affine, A. fraterculus and an unidentified Alexandrium sp. for which strain WEB-Alex-01 was assigned. It was ascertained that in spite of hot summer diverse Alexandrium species attaining up to four were distributed in the study area, in contrast with the long empirical recognition that the emergence of Alexandrium species is restricted to cooler seasons like spring or autumn in Korean coastal waters. Morphology and genetic characteristics of Alexandrium sp. strain WEB-Alex-01 are different from any other previously reported Alexandrium species from Korean seas, which implies that further studies on taxonomic, physiological, ecological and toxicological properties of the newly recorded Alexandrium species are needed.

• Journal of Wetlands Research
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• v.18 no.4
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• pp.386-393
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• 2016

Agricultural ecosystem is recognized as a space for providing a variety of services, in addition to the food production that it originally encompassed, such as water purification, biological habitat, air purification, soil conservation, and landscape development. The construction of greenhouses in agricultural landscapes can cause deterioration of ecosystem services because of the increase of impermeable area and loss of biological habitats. This study aimed to compare insect diversity between different types of constructed greenhouses and paddy ecosystems. The target study area was selected by considering the distribution status of horticultural complexes and was classified as Single Vinyl Greenhouse, Multi Vinyl Greenhouse or Glass Greenhouse and they were compared with four paddies. The study locations were in Gu-Mi, Bu-Yeo, Ginje and Jin-Ju. A total of 2,333 individual insects belonging to 9 orders, 38 families, 76 genus, and 80 species were collected. The composition of orders was Hemiptera (22.37%), Coleoptera (18.42%), Hymenoptera (14.47%), Orthoptera (11.84%), and Diptera (10.53%). The average number of collected species were in the order Paddy (39.38 species) > Single Vinyl Greenhouse (35.50 species) > Multi Vinyl Greenhouse (22.50 species) > Glass Greenhouse (24.00 species). The Diversity Index (H') was Paddy (4.76) > Single Vinyl Greenhouse (4.57) > Multi Vinyl Greenhouse (4.12), and Glass Greenhouse (4.12). The Richness Index (RI) was Paddy (7.72) and Single Vinyl Greenhouse (7.03) > Multi Vinyl Greenhouse (4.99) and Glass Greenhouse (5.32). From our results, it can be seen that the biological diversity features of insects decreased when greenhouses are constructed.However, Single Vinyl Greenhouse is noted to promote insect diversity more than that by Multi Vinyl Greenhouse and Glass Greenhouse. Hence, when constructing greenhouses, it is necessary to consider insect habitat to conserve insect diversity.

• Journal of Information Display
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• v.9 no.3
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• pp.33-38
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• 2008

A simple ray tracing model is developed to establish the relationship between the distributions of observed visible light and the excited Xe species in a PDP cell. The ray tracing model can obtain the density distribution of the excited Xe species. It shows the two independent discharge modes created during a single period of sustaining discharge. The maximum density of excited Xe species is located about $148{\mu}m$ away from the center of the gap between two sustaining electrodes. We also found the loss rate of VUV photons by comparing the luminance profile predicted in our theoretical model from experimental results. According to calculations based on our model, only about 22 percent of the photons can impinge the phosphor layer.

• Korean Journal of Ichthyology
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• v.32 no.1
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• pp.32-36
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• 2020

A single specimen of Glossogobius olivaceus was collected from Ulsan, Korea in May 2015, representing the first identification of the species in Korean waters. This species is characterized by several blackish dots on the nape, developed sensory pores and papillae on the head, 33 lateral line scales, and 27 vertebrae. The newly proposed Korean names of the genus and species are "Geom-eun-ban-jeom-mang-duk-sok" and "Geom-eun-ban-jeom-mang-duk", respectively.

• Journal of Microbiology and Biotechnology
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• v.10 no.5
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• pp.651-655
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• 2000

Polymerase chain reaction (PCR) was used to specifically detect Phytophthora infestans by analyzing the sequences of the ribosomal internal transcribed spacer regions (ITS) in the rDNA of the Phytophthora species. Based on the sequence data, PISP-1 together with the ITS3 primer were used to detect p. infestans. A single ca. 450 bp segment was observed in P. infestans, but not in the other fungal or bacterial isolates. Two factors, the annealing temperature and template DNA quantity, were investigated to determine the optimal conditions. Using these species-specific primers, a unique band was obtained within annealing temperatures of $55^{\circ}C$-$61^{\circ}C$ and template DNA levels of 10 pg-100 ng.

• Animal Systematics, Evolution and Diversity
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• v.28 no.3
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• pp.212-214
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• 2012

The Cymatium Roding, 1798 is a small- to large-sized marine gastropod genus. Three species has been reported thus far for Cymatium in the Korean waters. In general, Cymatium encausticum (Reeve, 1844) is known to occur in tropical seawaters including the Philippine Islands along with its congeners C. gutturnium, C. springsteeni, and C. exile. A single individual of the species was collected from Jejudo Island by SCUBA diving and morphological features were observed using a stereomicroscope. This is the first study to report the occurrence of Cymatium encausticum (Reeve, 1844) from the Korean waters, providing a detailed description of the species with the illustration for the shell morphology.

• Animal Systematics, Evolution and Diversity
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• v.26 no.3
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• pp.317-320
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• 2010

A single specimen (149.9 mm TL) of sagami grenadier, Ventrifossa garmani was collected from Korea waters. This species is similar to Coelorinchus spp. in body shape, but is distinguished by a short and rounded snout. It is characterized by having the serrated second dorsal spine in the first dorsal fin, a triangular spine on the scale, seven branchiostegal rays and six scales below middle of first dorsal fin. We describe this species as the first record to Korean fish fauna and propose the Korean name "Kkeo-kkeul-meo-ri-min-tae-sok" for this genus, and "Kkeo-kkeul-meo-ri-min-tae" for this species.

• The Korean Journal of Ecology
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• v.1 no.1
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• pp.11-16
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• 1977

The vertical distribution of the corticolous lichens in Mt. Sobaeg was detected by 10cm point quadrat. The dominant species of lichens was arranged in a single dimensional ordination along the elevational gradient with the frequency percentage of the species. Cetraria stracheyi, Parnaria leucosticta, Stieta platyphyll and Parmelia petusa were found in order of abundant from lower, Samgadong(400m) to higher, Birobong(1439m) in which they occurred mainly on the southwest slope. However, such species as Cetraria juniperina was more abundant than Parnaria leucosticta and Stieta platyphylla at the southeast slope. The distribution of Cetraria Stracheyi and Parnaria leucosticta was limited below 1200m height, while Parmelia petusa and Cetraria juniperina mostly above 900m height.