• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.3
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• pp.175-194
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• 2014

This study attempts to identify the spatial distributions of Achnanthes convergens, and elucidate the environmental factors that affect the Periphyton diatom habitat. Data in 250 points of Nakdong river basin are collected between April(primary) and September(secondary) 2012, with the National Institute of Environmental Research's support. We define "clean area" over 10% of Achnanthes convergens appearance, and the others as "non-clean areas". Spatial statistics of Kriging, Hotspot, LISA are used in this study. Results show that 1) 56 points are identified as clean areas in the primary survey, while 41 points are discovered in the following survey; 2) using water quality variables, density of turbidity(clean $101.83{\mu}s/cm$; non-clean $598.48{\mu}s/cm$) and conductivity(clean 1.95 NTU; nonclear 5.58 NTU) are five-fold lower in clean-areas; 3) Habitat and Riparian Factors in Nakdong basin illustrate that natural sand bar, diversity of velocity, sediment condition, levee material, riverside land affect Achnanthes convergens; 4) Hotspots of Achnanthes convergens are located in watersheds, including upper Andong Dam, upper Imha dam, Wi-cheon, Miryang river, Nam river and Hwang river whereas mainstream/downstream of Nakdong river and Keumho river watershed are shown as coldspots.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.920-926
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• 2010

Marine alga, Chlorella vulgaris, was extracted by chloroform-methanol (2:1, v/v) solvents for lipid extraction at $35^{\circ}C$ for five hours (HCM-35) and its process was compared with conventional lipid extraction condition such as chloroform-methanol (2:1, v/v) at $65^{\circ}C$ for one hour (CM-65). This low temperature extraction process showed that 80% of total lipid was extracted and its residues contained relatively unchanged amounts of intact proteins and other minerals as well as amino acid profiles. Interestingly enough, the weight fraction of carbohydrate in the residues slightly increased due to less denaturation at low process temperature. The biological activities of the residues such as cytotoxicity and immune cell growth activation were not much changed after being extracted. The sensory evaluation were found to be very favorable for being used as a food additive and/or food supplement. This result could also help to maintain the economic feasibility of utilizing marine resources in food and other relevant industries.

• Journal of Mushroom
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• v.13 no.2
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• pp.119-124
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• 2015

This study was carried out to characterize the chemical components of Flammulina velutipes during storage by different packaging film application for developing export winter mushroom to south east asia area. Changes of weight and growth rate from Flammulina velutipes were the lowest in testing packaging film at $15^{\circ}C$ among the films. The pH changes of Flammulina velutipesg was the highest in imported packaging film at $25^{\circ}C$. The changes of colors was measured by Hunter's color value, L value and yellowness (+b) were slightly decreased during storage. But the L value and yellowness (+b) were not affected by packaging films. Six organic acids were detected such as oxalic acid, lactic acid, malic acid, citric acid, acetic acid and succinic acid. The content of total organic acids were increased by storage period.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.8
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• pp.420-427
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• 2016

This study was conducted on the sediment remediation using micro-bubble to remove fine particles. For this study, characteristics of contamination and release in sediment were analyzed. And then, the characteristics of bubbles on removal efficiency was investigated at various operation conditions. In particle size distribution of the sediment used for the study, the proportion of clay and silt (<0.075 mm) was about 7.7%, sand (0.075~4.75 mm) was about 67.8%, and gravel (${\geq}4.75$) was 24.5%. Total nitrogen (TN) and total phosphorus (TP) of the sediment were 2,790~3,260, 261~311 mg/kg respectively. Ignition loss and water content were 4.1~9.6, 32.9~53.2% respectively. In analysis of removal efficiency according to operation conditions of micro-bubble, it was the highest when operation condition is pressure 6 atm, pressurized water ratio 30%, and coagulant dosage 15 ppm. At the time, the sediment's removal efficiency was 19.9%. Accordingly removal efficiency of TN and TP were 21.4, 22.6% respectively. Finally a research was found that fine particles in sediment were almost removed by micro-bubble, which led to decrease nutrients' release at about 20.1~64.3% in comparison to sediment including lots of fine particles.

• Progress in Medical Physics
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• v.19 no.2
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• pp.131-138
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• 2008

We evaluated on the calculation accuracy of treatment planning system (TPS) with phantom having convex and concave surface. The TPS is Eclipse (Varian, USA) using both algorithms AAA and PBC for photon dose calculations. PBC algorithms have three corrections of Batho, modified Batho (M-Batho), and equivalent TAR (E-TAR). The field sizes were $10{\times}10\;cm^2$ and $20{\times}20\;cm^2$, and MLC-shaped fields for these fields. We measured doses at three depths 5, 10 and 15cm in phantom of SSD=90cm in the condition of inserted farmer chamber. For given conditions, we have calculated dose with these algorithms and compared them with measured doses. In AAA the calculated doses (dose/MU) were agreed to measured doses within ${\pm}1%$ in flat and convex surface and were under estimated with -1.9% maximum in concave surface. In PBC the calculated doses were over estimated with +1.7% and +4.1% respectively in flat and convex surface and the differences were from -3.1% to +2.1% in concave surface. In comparison of criteria from AAPM and IAEA reports, and statistical analysis for these results, it is found that the AAA's results are in good agreement with measured values and the M-Batho's results are generally good agreed with measured values among PBC algorithms.

• Korean Journal of Environment and Ecology
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• v.26 no.2
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• pp.210-218
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• 2012

This study was carried out to analyze the vegetation properties, soil characteristics and ordination of Bletilla striata population in South Korea. The $Bletilla$ $striata$ population was classified into $Juniperus$ $rigida$ dominant population, $Rhododendron$ $yedoense$ var. $poukhanense$ dominant population, $Rhus$ $javanica$ dominant population, $Bletilla$ $striata$ typical population. $Bletilla$ $striata$ were mainly distributed along the coast of south-western regions of the Korean penninsula and it's population was located at an elevation of 4m to 40m. In the study sites, soil organic matter, total nitrogen, available phosphate, exchangeable potassium, exchangeable calcium, exchangeable magnesium, cation exchange capacity and soil pH were 2.38-6.70%, 0.09-0.27%, 1.81-6.85mg/kg, 1.08-1.72$cmol^+/kg$, 3.56-7.71$cmol^+/kg$, 1.52-3.21$cmol^+/kg$, 5.28-16.95$cmol^+/kg$ and 4.60-6.01 respectively. $Rhododendron$ $yedoense$ var. $poukhanense$ dominant population was found in the steep sloped area that has high percentage of organic matter, total nitrogen, cation exchange capacity and pH than other populations. $Rhus$ $javanica$ dominant population was found in the gentle sloped area that has less percentage of organic matter, total nitrogen, cation exchange capacity and pH. $Juniperus$ $rigida$ dominant population and $Bletilla$ $striata$ typical population were found in the medium sloped area that has medium percentage of organic matter, total nitrogen, cation exchange capacity and pH. Current status of $Bletilla$ $striata$ habitats is very vulnerable with local development constantly threatening the species' survival. Thus, concrete conservation plans to protect natural habitats should be set up as soon as possible.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.211-218
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• 2013

This study was conducted to investigate the quality characteristics of eight Kimchi cabbage cultivars and the effect of cold storage on the quality of two kinds of cabbage cultivars, such as 'CR-Nongshim', and 'Ryouckgwang'. Early planted and harvested cultivars at July showed that fresh weight was lower than late harvested cultivars at September, because early harvesting time of July was heavy rainy season at highlands of Gangwon province. The firmness was more than 10 N for all cultivars and 'Cheongock', 'Sanjanggoon', and 'Ryouckgwang' cultivars had high value of firmness among them. No differences among the cultivars were found in appearance, freshness, and texture evaluations at harvest. Sweetness and bitterness had statistical differences and showed high value in 'Ryouckgwang' and in 'CR-Nongshim' and 'Sooho'. Two Kimchi cabbage cultivars such as 'CR-Nongshim' and 'Ryouckgwang' were stored at $0^{\circ}C$, $2^{\circ}C$, $5^{\circ}C$, and room temperature ($25^{\circ}C$) with more than 90% RH. Significant difference was found in weight loss during room and low temperature storage. In general, weight loss of the Kimchi cabbages at room temperature was significantly increased by 15% within 3 days, whereas it was delayed at low temperature until 3 weeks on all Kimchi cabbage cultivars. Firmness of 'CR-Nongshim' was higher than 'Ryouckgwang' but there was no difference within low storage temperatures. Appearance among the sensory factors was a critical indicator to estimate storage periods. On the point of appearance, storage period at $0^{\circ}C$ was 1 week and $2^{\circ}C$ and $5^{\circ}C$ was 3 weeks and 1 week in 'CR-Nongshim' cultivar, respectively. The storage period of 'Ryouckgwang' cultivar was 2 weeks, 4 weeks, and 2 weeks, respectively. Conclusively, storage at $2^{\circ}C$ with more than 90% RH was recommended as optimum temperature to maintain quality in both cultivars.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.3
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• pp.411-421
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• 2006

In children, during developing occlusion stage, many studies confirm a high prevalence of gingival inflammation. Prevention, early diagnosis and treatment of gingival and periodontal disease is important because by establishing excellent oral hygiene habits in children, the risk of periodontal disease can be on the decrease in adulthood. This study evaluated the gingival conditions of 50 children$(8.5{\pm}3.1years)$ and 20 $adults(26.1{\pm}3.3 years)$ receiving clinical examination and GCF test at the pediatric dentistry of Chonbuk national university hospital in Jeonju, Korea. I estimated children's and adult's gingival states by measuring gingival crevicular fluid(GCF) using Periopaper and $Periotron^{(R)}$ 8000, gingival index, plaque index, DMFT scale. The results were as follows : 1. There are no statistical differences of GCF volume among the groups of the primary dentition, tooth erupting stage, complete eruption stage(p>0.1). But mean value of GCF is highest at the tooth erupting stage. 2. Comparing with adults, children have higher mean value of GCF volume with statistical differences (p<0.001). 3. There is statistically positive relationship between volume of GCF and gingival index (GI), plaque index(PLI) in both adults and children(GI; r=0.394, PLI ; r= 0.642). 4. There is no relationship between GCF volume and dental caries, composite resin treatments (p>0.05). But There is statistically positive relationship between GCF and orthodontic treatments(p<0.001) 5. Primary dentition has higher mean value of DMFT than permanent dentition(p<0.001). But there is no statistical relationship between GCF and DMFT (p>0.1).

• The Korean Journal of Pesticide Science
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• v.16 no.4
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• pp.273-281
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• 2012

This study was conducted for the establishment of the analytical method of pesticide residues in rice straw for 9 pesticides; etofenprox, tricyclazole, diazinon, edifenphos, propiconazole, carbaryl, carbofuran, 3-hydroxy carbofuran and 3-keto carbofuran and for the monitoring of these pesticides in rice straw for livestock feed in Korea. These pesticides were classified into 4 groups according to analytical instrument condition. Group 1 (HPLC-UVD1) included tricyclazole and etofenprox while group 2 (HPLC-UVD2) included propiconazole and edifenphos. Group 3 (HPLC-FLD) included carbaryl, carbofuran, 3-hydroxy carbofuran and 3-keto carbofuran. Group 4 (GC-NPD) included Diazinon. The dried rice straw samples were extracted with acetone and purified by liquid-liquid partition and solid phase extraction (SPE): Combination of Florisil SPE and amino-propyl SPE was used for group 1 and group 2, amino-propyl SPE for group 3, and Florisil SPE was for group 4. Recovery was in the ranged 70~110% and the limits of quantitation (LOQ) were lower than the half of maximum residue limits. Therefore this method was proved to be efficient for monitoring of these pesticides residue in rice straw. A total of 18 rice straw samples from 6 provinces in Korea in 2010 were analyzed using established method and, only 3-keto carbofuran was detected in one sample at concentration of 0.04 mg/kg.

• Journal of Environmental Impact Assessment
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• v.24 no.2
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• pp.134-153
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• 2015

When making urban planning, it is important to understand climate effect caused by urban structural changes. Seoul city applies UPIS(Urban Plan Information System) which provides information on urban planning scenario. Technology for analyzing climate effect resulted from urban planning needs to developed by linking urban planning scenario provided by UPIS and climate analysis model, CAS(Climate Analysis Seoul). CAS develops for analyzing urban climate conditions to provide realistic information considering local air temperature and wind flows. Quantitative analyses conducted by CAS for the production, transportation, and stagnation of cold air, wind flow and thermal conditions by incorporating GIS analysis on land cover and elevation and meteorological analysis from MetPhoMod(Meteorology and atmospheric Photochemistry Meso-scale model). In order to reflect land cover and elevation of the latest information, CAS used to highly accurate raster data (1m) sourced from LiDAR survey and KOMPSAT-2(KOrea Multi-Purpose SATellite) satellite image(4m). For more realistic representation of land surface characteristic, DSM(Digital Surface Model) and DTM(Digital Terrain Model) data used as an input data for CFD(Computational Fluid Dynamics) model. Eight inflow directions considered to investigate the change of flow pattern, wind speed according to reconstruction and change of thermal environment by connecting green area formation. Also, MetPhoMod in CAS data used to consider realistic weather condition. The result show that wind corridors change due to reconstruction. As a whole surface temperature around target area decreases due to connecting green area formation. CFD model coupled with CAS is possible to evaluate the wind corridor and heat environment before/after reconstruction and connecting green area formation. In This study, analysis of climate impact before and after created the green area, which is part of 'Connecting green network across the north and south in Seoul' plan, one of the '2020 Seoul master plan'.