• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.385-393
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• 2016

In this study, we analyzed th Cheonggyecheon watershed for urban flood risk index. SWMM model configuration based on each watershed data. And it was set as the final index calculated indicators related to the humanities, social and environmental. Each indicator was standardized and weighted using the Delphi method. Finally, select the danger area through urban flood risk index. Determined 12 indices according to the hazard and vulnerability. Vulnerability is selected the index divided by three factors. 21 watersheds were analyzed through urban flood risk index. The top of three areas of index is Jeongneung 1, Majang, Pil-dong, each index is 0.533, 0.494, 0.381. The lowest index is soongin 0.216. Urban flood risk index developed in this study can be applied to other regions in Korea for establishing national water resources management plan.

• Journal of Korea Water Resources Association
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• v.41 no.1
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• pp.87-100
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• 2008

The alternative evaluation index (AEI) is developed and applied to determine the priorities of some options for integrated watershed management. Based on the results of continuous simulation model, AEIs of some feasible alternatives are calculated using multicriteria decision making techniques and sustainability evaluation model, DPSIR (Drivers-Pressure-State-Impact-Response).

• Journal of Environmental Science International
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• v.17 no.8
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• pp.879-889
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• 2008

Community structure of benthic macroinvertebrates was investigated from Gigye stream, Pohang, Korea from May to November, 2007. As results, total of 108 species of macroinvertebrates under 49 families, 15 orders, 5 classes in 3 phyla were identified. The number of species was the most abundantly revealed in aquatic insects (class Insecta) with 86 species (82.6%) under 7 orders. The phylum Mollusca (10 species, 9.2%) and the phylum Annelida (6 species, 5.6%) were followed in order. In the class Crustacea, 6 species (5.6%) were distributed. In aquatic insects, the order Odonata was the most abundant taxon (20 species, 23.3%). Seventeen species (19.8%) of the order Ephemeroptera and 16 species (18.6%) of the Coleoptera were followed. The primary dominant species in the stream was Cloeon dipterum of Ephemeroptera. For community analysis, the values of diversity index (H'), evenness index (J'), dominance index (DI) and richness index (RI) were studied and the average values of them were 5.65, 0.84, 0.13, and 13.18, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.5
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• pp.429-434
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• 2007

This study was conducted to estimate site productivity of Quercus acutissima and Quercus mongolica by four forest climatic zones. We used site environmental variables (28 geographical and pedological factors) and site index as a site productivity indicator from nation-wide 23,315 stands. Based on multiple regression analysis between site index and major environmental variables, the best-fit multivaliate models were made by each species and forest climatic zone. Most of site index prediction models by species were regressed with seven to eight factors, including altitude, relief, soil depth, and soil moisture etc. For those models, three evaluation statistics such as mean difference, standard deviation of difference, and standard error of difference were applied to the test data set for the validation of the results. According to the evaluation statistics, it was found that the models by climatic zones and species fitted well to the test data set with relatively low bias and variation. Also having above middle of site index range, total area of productive sites for the two Quercus spp. estimated by those models would be about 6% of total forest area. Northern temperate forest zone and central temperate forest zone had more productive area than southern temperate forest zone and warm temperate forest zone. As a result, it was concluded that the regressive prediction with site environmental variables by climatic zones and species had enough estimation capability of forest site productivity.

• Journal of Environmental Science International
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• v.30 no.8
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• pp.621-628
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• 2021

The characteristics of time changes in air temperature, DI (discomfort index) and WBGT (wet-bulb globe temperature) were investigated for inland city (daegu) and coastal city (pohang) of Gyeongbuk Province during the 2018 consecutive heat wave season. The time when the temperature dropped below 33℃ was around 19h in both regions. As such, the two regions were similar with respect to the time up to which the heatwave warning levels continued. However, the discomfort index (DI) was higher than 27 in Pohang. Most people feel unpleasant when an discomfort index of 27 or higher appears. The results indicated that Korea's night-time thermal environment during the summers is particularly poor in the southern coastal areas. WBGT began at 09:00 and lasted until 21:00, with a score of 31 or higher; this score, in principle, corresponded with the duration of outdoor activity in both regions. Therefore, it was found that outdoor work was at a level where all day long had to be stopped in both areas during the heat wave. Although time changes in temperature and WBGT were similar in both regions, Discomfort Index (DI) differed significantly. The difference refers to the fact that Pohang is strongly affected by the high heat capacity effect and the supply of water vapor from the sea.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.2
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• pp.7-12
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• 2009

The effects of refining either SwBKP or HwBKP, and both of SwBKP and HwBKP on the physical properties of paper were investigated in order to elucidate if the non-conventional refining and blending method can be used for the optimizing the paper properties. The blending ratio of SwBKP and HwBKP was 15:85. The highest bulk was obtained with the refining of SwBKP only. Any differences of opacity were not observed in unfilled paper, while the highest opacity of PCC filled paper was obtained at same bulk when the only HwBKP was refined. However burst index and tensile index did not showed any differences in the relationship with bulk. Therefore this result can be applied to improve the opacity of paper without sacrificing of strength properties.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.1
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• pp.41-53
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• 2015

This study was performed to assess the level of ozone risk for wheat in the central region of the Korean Peninsula by using two ozone indices, the ozone-concentration based index (AOT40) and the ozone-flux based index ($AF_{st}Y$), and to analyze the relationship between the two indices. In the present study for $AF_{st}Y$ calculation, the Monin-Obukhov length was estimated using the Pasquill stability class which was determined from routine meteorological data such as wind speed, solar radiation and cloudiness. The AOT40 and $AF_{st}6$ indices were calculated for wheat at 3 sites in the central region of the Korean Peninsula during a period of 3 months from April 1 to June 30, 2006. It should be noted that the estimation of ozone index $AF_{st}6$ in this study was performed under several assumptions. The results for both indices, AOT40 and $AF_{st}6$, showed that agricultural crops could be seriously damaged by ozone in the local region of the Korean Peninsula.

• Journal of Korean Society on Water Environment
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• v.26 no.5
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• pp.796-801
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• 2010

Water quality index (WQI) can be a great tool that allows experts to translate large amount of complex water quality data into a format more easily understood by the public and policy makers. Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) can be calculated with the three factors (Scope: $F_1$, Frequency: $F_2$, Amplitude: $F_3$). After all, the WQI for a specific site is produced as a number between 0 to 100; the scale is also divided into five categories, i.e., Excellent, Good, Fair, Marginal and Poor. The WQI was found to be highly related to Chl-a, pH, temperature among the collected items. When the more input parameters were used, the range of variation generally became smaller. $F_3$ among the factors of WQI was influenced by algae. It showed a similar variation tendency between WQI and algal bloom in 2008.

• Journal of Environmental Impact Assessment
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• v.8 no.3
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• pp.77-90
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• 1999

The degree of green naturality (DGN) has played a key role for maintaining the environmental quality from inappropriate developments, although the quality and effectiveness of the mapping of DGN has been under debate. In this study, spatial distribution of degree of green naturality was initially estimated from forest stand maps that were produced from the aerial photo interpretation and extensive field survey. Once the boundary of initial classes of DGN were defined, it were overlaid with normalized difference vegetation index (NDVI) data that were derived from the recently obtained Landsat Thematic Mapper data. NDVI was calculated for each pixel from the radiometrically corrected satellite image. There were no significant differences in mean values of vegetation index among the initial DGN classes. However, the satellite derived vegetation index was very effective to delineate the developed and damaged forest lands and to adjust the initial value of DGN according to the distribution of NDVI within each class.

• Korean Journal of Environmental Biology
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• v.23 no.3 s.59
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• pp.215-220
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• 2005

Through multiple stage analysis, the biochores in Korea were classified and organized as a hierarchy system. In the 1st step, the isopleth lines of warmth index $100^{\circ}C,\;85^{\circ}C,\;55^{\circ}C\;\cdot$ month and the coldness index $-8^{\circ}C,\;or-10^{\circ}C\;\cdot$ month, which indicate the boundaries of plant formation zones (Yim and Kira 1975; Yim 1977), were applied in the determination of major biochores. In the 2nd step, these biochores were subdivided into the five classes based on Thornthwaite's moisture index (Im) and Yim and Kira (1976), as follows: $100{\le}Im,100 In the 3 rd step, the analysis of topographic features yielded three categories of flatlands, gentle slope, and steep slope areas. These were obtained by adopting the $100{\times}100-meter$ gridded DEM and by considering the physical features of the Korean Peninsula. The features of relief in mountainous areas, waters, islands, etc. were converted into climatic indices. This grouping of biochores serves as a useful tool for the interpretation of the distributional patterns of vegetation of vascular plants and similar phenomena.