• Korean Journal of Ecology and Environment
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• v.41 no.3
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• pp.338-347
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• 2008

Grazing rate (GR) and feces production (FP) of freshwater snail Cipangopaludina chinensis malleata on two hibernal diatom communities were examined in a laboratory. Snail with the similar size (4.2$\sim$5.8 cm) were collected from the Gunsan and Okgu district (Jeonbuk), transferred to the artificial management system in laboratory, and starved for 3 day before the experiment. The feeding experiments were conducted at various conditions such as passage of time (0, 1, 4 and 7 hr), snail density (0.0, 0.5, 1.0, 2.0 and 4.0 ind. $L^{-1}$) and kinds of prey (cold lake and stream water). One prey used in this study is the water of Lake Ilgam, the other is that of Han river. Lake Ilgam water was dominated by Synedra ulna (69.1%) and Scenedesmus sp. (6.6%), while Han river was by Asterionella formosa (69.4%) and Diatoma vulgare (27.7%). With the increment of snail density and time, the Chl-a concentration of two experimental waters were clearly decreased. Chl-a of Han river rapidly was decreased after 1 hour of snail treatment, while that of Ilgam lake was decreased after 4 hour. On the passage of time, a highest GR (1.94 L $g^{-1}\;h^{-1}$) showed at 1 hr, and then, decreased gradually to 0.04 L $g^{-1}\;h^{-1}$ by 7 hr. The highest FP (0.11 mg $L^{-1}$) showed at 7 hr. These results indicate that native snail Cipangopaludina chinensis malleata may be applied as a potential bio-filter to control diatom blooms in the cold lake and stream.

• Research in Plant Disease
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• v.15 no.1
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• pp.54-56
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• 2009

Stem rot of perennial statice (Limonium sinuatum) was observed in Un bong, Jeonbuk from 2006 to 2007. Affected plants were randomly distributed in the greenhouses and infection rate was more than 10%. Stem and leaf of statice at soil line were dried and turned brown, initially. As the disease became severe, other stem parts and crowns were turned dark brown and then sunken. The fungal isolates were showed initially white aerial mycelium and turned brown with age. They produced few sclerotia which small, irregularly shaped with pinpoint sized. Mycelia were branched at $90^{\circ}$ angles and multinucleate in one cell. The pathogenicity of causal organism was proved according to Koch's postulates. The causal fungus of stem rot was identified as Rhizoctonia solani based on the cultural and morphological characteristics. This is the first report on stem rot of statice by R. solani in Korea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.3
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• pp.139-146
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• 2011

In order to detect the early impacts of the Hebei Spirit oil spill on the subtidal macrozoobenthos, we conducted a benthic survey at 72 stations in the subtidal area of Tae-an, the eastern Yellow Sea from Dec. 18th 2007 to Dec. 22th after 10 days from the Hebei Spirit oil spill. A total of228 species from 72 stations was sampled with mean density of 561 ind $m^{-2}$ and mean biomass of 39.7 gww $m^{-2}$. In this study, Ampelisca occurred as a major dominant fauna in this survey, but did not appear around oil spill areas. Meanwhile some opportunistic polychaete worms like Prionospio bocki, Prionospio cirrifera appeared in the oil spill area, especially near coastal beaches. The overall abundance and biomass of macrozoobenthos decreased after oil spill. However some stations previously disturbed with sand extraction showed a similar macrozoobenthic community structure.

• Journal of the Korean Wood Science and Technology
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• v.33 no.4 s.132
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• pp.53-59
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• 2005

This study was performed to understand the changes in wood extractives, mainly acetone extracts, in pine woods (Pinus densiflora and Pinus rigida) treated by three blue stain fungi (BSF) such as native BSF in Korea, Leptographium sp., screened Albino strain (BSFcs-1) and commercial Cartapip. BSF treatment has significantly reduced acetone extracts, 25.1~30.4% decreasing in red pine and 22.9~28.1% in pitch pine. The decreasing rates of fatty acids and sterols in woods were 10.6~11.2% by 3 week aging and 36~41.1% by BSF treatments, respectively. Triglycerides were also decreased to 5.68~9.4% by 3 week aging and 38.5~40.0% by BSF treatments, respectively. Resin acids were 6.1~11.3% by 3 week aging and 36~41.5% by BSF treatments, respectively. There were not so significant differences in extracts among native BSF and Albino-type strains (Albino strain, BSFcs-1, and commercial Cartapip). It was known that the Albino strain (BSFcs-1) screened for the biocontrol of wood discoloration has effectively decreased acetone extractives in pine woods.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.2 s.302
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• pp.19-26
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• 2005

After various video coding standards such as H.263, MPEG-4, and H.264 have been introduced, there has bun strong need to support the multiple standards with limited resources efficiently. In terms of deblocking Inter which plays an important role in improving visual quality, K264 deblocking filter implementation has different aspects as compared with traditional $8\times8$ block-based post-filter implementation. Analyzing the differences, this paper proposes a H.264 deblocking filter implementation method that supports $8\times8$ block-based post-filtering for the traditional video coding systems. In the proposed implementation method the block boundaries to he filtered are adaptively chosen for $8\times8$ and $4\times4$ block boundary filtering. Since the filtered result is selectively used for motion compensation or not, both loop-filtering and post-filtering can be achieved. A quantization parameter conversion unit that converts H.263 quantization parameters to H.264 quantization parameters is utilized by examining the $8\times8$ block boundary errors based on human visual system. Since the original nature of the H.264 deblocking filter is well expanded to the $8\times8$ block-based post-filter with minor modifications, the proposed implementation method is suitable to implement the deblocking function of the multiple video standards such as H.263, MPEG-4, and K264, efficiently.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1507-1514
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• 2008

Cholesterol oxidase catalyses the conversion of cholesterol to 4-cholesten-3-one. This enzyme has been used for clinical assay of human serum cholesterol and for reduction of cholesterol level in foods and feeds. In order to search the microorganism which has a high extracellular and stable activity of cholesterol oxidase, soil microorganisms were screened. As a result, the one with the highest extracellular cholesterol oxidase activity was obtained and named as the BEN 115. The BEN 115 strain was identified as one of the Nocardia species based on our taxonomic studies. The cholesterol oxidase from this strain was shown to have two bands of extracellular proteins on SDS-PAGE and Western blot. Their molecular masses were estimated to be about 55 and 57 kDa, respectively. In addition, this cholesterol oxidase was considerably stable at the broad range of pH $3.5{\sim}9.5$ and at the temperature of $25{\sim}55^{\circ}C$. The optimum pH and temperature of this cholesterol oxidase were pH 5.5 and $35^{\circ}C$, respectively. The activity of extracellular cholesterol oxidase could be enhanced 1.6 to 2.0 folds by the addition of nonionic detergent such as Triton X-114, Triton X-100, or Tween-80 into the culturing broth. The substrate specificities against campesterol, sitosterol and stigmasterol were measured to be 50%, 50%, and 27%, respectively, compared to the cholesterol. These results suggest that Nocardia sp. BEN 115 may be useful as a microbial source of cholesterol oxidase production.

• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.198-205
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• 1999

Cucurbitaceous vegetable crops grown in greenhouses in Korea were surveyed from 1995 to 1997. Incidence of Sclerotinia rot was as high as $30{\sim}70%$ at its maximum on Cucumis melo var. reticulatus (netted melon), Cucumis sativus (cucumber), Cucurbita moschata (pumpkin) and Cucurbita pepo (summer squash) but relatively low on Citrullus lanatus (watermelon) and Cucumis melo var. makuwa (oriental melon). Symptoms of Sclerotinia rot developed on stems of all the cucurbits, fruits of five cucurbits except C. lanatus, petioles of two Cucurbita spp. and leaves of C. moschata. A total of 126 isolates of Sclerotinia sp. were obtained from the lesions and identified as Sclerotinia sclerotiorum based on the morphological and cultural characteristics. The fungus was very frequently isolated from stems and fruits of the cucurbits but rarely from petioles and leaves. Six isolates of the fungus were pathogenic to six cucurbits tested although there was some difference in virulence among the isolates to some of the hosts. C. lanatus was the most susceptible to the isolates, whereas C. melo var. makuwa was the most resistant. C. melo var. reticulatus and C. sativus were relatively susceptible to the isolates, and C. moschata and C. pepo relatively resistant.

• Korean Journal of Microbiology
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• v.45 no.1
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• pp.63-68
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• 2009

The exo-polysaccharide producing microorganism, Aureobasidium pullulans IMS-822, was isolated and identified from soil. The viscosity-average molecular weight of exo-polysaccharide was calculated as $8.9{\times}10^5$ by Mark-Houwink equation. The sugar component of exo-polysaccharide was determined as glucose by HPLC analysis. The IR spectra indicated that the exo-polysaccharide has an absorption peak at 890 $cm^{-1}$ for the ${\beta}-configuration$ of D-glucan. The $^{13}C$ NMR signal at ${\delta}$ 86.62 ppm arose from the substituted C-3 of glucose. The signal at ${\delta}$ 72.11 ppm was assigned to C-6 of branched ${\beta}-(1{\to}3)-D-glucosyl$ residues. Viscosity and Congo red reaction indicated that {\beta}-(1{\to}3)(1{\to}6)-glucan$ produced by A. pullulans IMS-822 has a highly ordered hydrogen-bond dependent conformation in aqueous solution, which collapses in strong alkaline solution.

• The Journal of Engineering Geology
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• v.24 no.4
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• pp.525-534
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• 2014

Environmental problems typically occurring in abandoned mine lands (AML) include: contaminated and acidic surface water and groundwater; stockpiled waste rock and mill tailings; and ground subsidences due to mining operations. This study examines the effectiveness of various geophysical techniques for mapping potential hazard and contaminated zones. Four AML sites with sedimentation contamination problems, acid mine drainage (AMD) channels, ground subsidence, manmade liner leakage, and buried mine tailings, were selected to examine the applicability of various geophysical methods to the identification of the different types of mine hazards. Geophysical results were correlated to borehole data (core samples, well logs, tomographic profiles, etc.) and water sample data (pH, electrical conductivity (EC), and heavy metal contents). Zones of low electrical resistivity (ER) corresponded to areas contaminated by heavy metals, especially contamination by Cu, Pb, and Zn. The main pathways of AMD leachate were successfully mapped using ER methods (low anomaly peaks), self-potential (SP) curves (negative peaks), and ground penetrating radar (GPR) at shallow penetration depths. Mine cavities were well located based on composite interpretations of ER, seismic tomography, and well-log records; mine cavity locations were also observed in drill core data and using borehole image processing systems (BIPS). Damaged zones in buried manmade liners (used to block descending leachate) were precisely detected by ER mapping, and buried rock waste and tailings piles were characterized by low-velocity zones in seismic refraction data and high-resistivity zones in the ER data.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.430-437
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• 1993

This study was carried out for high quality mirin Production by fusant F-50. Cellularly fused between Aspergillus oryzae 9-12 and Aspergillus shirousamii 6082-60. The conventional and the improvement methods in Mirin-making by F-50 showed high level of total sugar, reducing sugar and amino-nitrogen of 42%, 38% and 0.18%, respectively. Free amino acids in Mirin were found to 387.2 mg% glutamic acid, 283.8 mg% arginine, 244.0 mg% leucine, 218.0 mg% aspartic acid, 231.1 mg% alanine, 168.3 mg% serine and 148 mg% phenylalanine. Organic acids in Mirin were contained: oxalic acid, citric acid, malic acid, succinic acid, lactic acid, acetic acid and propionic acid. Sugars such as glucose, maltose, isomaltose, maltotriose, ribose, isomaltotriose and isomatotertraose were also found in Mirin. The clouding formation of Mirin made by F-50 showed 0.03 alcohol clouding, 0.08 water clouding and negative heat clouding.