• Elastomers and Composites
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• v.37 no.4
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• pp.224-233
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• 2002

This study has investigated the flame retardant properties of EPDM rubber with the addition of various flame retardants. Carbon black, stearic acid, zinc oxide cross-linking agent were mixed with EPDM rubber to produce the base rubber E0 without the addition of flame retardants. Phosphorus flame retardant Tricrecyl phosphate(TCP) was added to E0 in 0.5, 1, 1.5, 2 phr to make E1~E4 samples and red phosphorus was added in 3, 6, 9, 12 phr to make E5~E8 samples. A flame retardant of the bromine family Decabromodiphenyloxide(DBDPO), and a chlorinated paraffin retardant of the chlorine family was added to E0 in 3, 6, 9, 12 phr to make E9~E12 and E13~E16 samples, repectively. Basic physical properties such as tensile strength, tear strength and hardness were measured for all the rubber samples with various flame retardant additions. There was no substantial differences. On the other hand, Oxygen index and UL94 were measured to study flame retardant properties. From oxygen index measurements E0 sample showed a value of 23.5%, indicating the improvement of flame retardant properties. Also from UL94 measurements, it was found that addition of red phosphorus resulted in maximum flame retardant effect. It was found that increasing the amount of addition resulted in decreasing combustion rate and improving flame retardant effect regardless of the kind of flame retardant.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.5B
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• pp.459-469
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• 2010

This study is to develop a grid-based daily runoff model considering seasonal vegetation canopy condition. The model simulates the temporal and spatial variation of runoff components (surface, interflow, and baseflow), evapotranspiration (ET) and soil moisture contents of each grid element. The model is composed of three main modules of runoff, ET, and soil moisture. The total runoff was simulated by using soil water storage capacity of the day, and was allocated by introducing recession curves of each runoff component. The ET was calculated by Penman-Monteith method considering MODIS leaf area index (LAI). The daily soil moisture was routed by soil water balance equation. The model was evaluated for 930 $km^2$ Yongdam watershed. The model uses 1 km spatial data on landuse, soil, boundary, MODIS LAI. The daily weather data was built using IDW method (2000-2008). Model calibration was carried out to compare with the observed streamflow at the watershed outlet. The Nash-Sutcliffe model efficiency was 0.78~0.93. The watershed soil moisture was sensitive to precipitation and soil texture, consequently affected the streamflow, and the evapotranspiration responded to landuse type.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5B
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• pp.495-504
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• 2008

Evapotranspiration (ET) is an important state variable while simulating daily streamflow in hydrological models. In the estimation of ET, for example, when using FAO Penman Monteith equation, the LAI (Leaf Area Index) value reflecting the conditions of vegetation generally affects considerably. Recently in evaluating the vegetation condition as a fixed quantity, the remotely sensed LAI from MODIS satellite data is available, and the time series values of spatial LAI coupled with land use classes are utilized for ET evaluation. Four years (2001-2004) of MODIS LAI was prepared for the evaluation of Penman Monteith ET in the continuous hydrological model, SLURP (Semi-distributed Land Use-based Runoff Processes). The model was applied for simulating the dam inflow of Chungju watershed ($6661.3km^2$) located in the upstream of Han river basin. For four years (2001-2004) dam inflow data and meteorological data, the model was calibrated and verified using MODIS LAI data. The average Nash-Sutcliffe model efficiency was 0.66. The 4 years watershed average Penman Monteith ETs of deciduous, coniferous, and mixed forest were 639.1, 422.4, and 631.6 mm for average MODIS LAI values of 3.64, 3.50, and 3.63 respectively.

• Korean Journal of Environmental Biology
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• v.42 no.1
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• pp.28-45
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• 2024

This study was conducted to investigate the flora of Sonjukdo Island(Yeosu-si), Korea. From results of four field surveys from April 2023 to October 2023, we identified 483 total taxa, representing 440 species, seven subspecies, 35 varieties, and one hybrid. They were placed in 322 genera and 109 families, including 249 taxa newly recorded in this study. Among them, four taxa were endemic to Korea, four taxa were IUCN red list plants, and 22 taxa were climate sensitive indicator plants. Floristic target plants amounted to 99 taxa, including two taxa of grade IV, 41 taxa of grade III, 10 taxa of grade II, and 46 taxa of grade I. A total of 54 taxa of alien plants were identified, with a Naturalized Index of 11.2% and an Urbanization Index of 13.8%. Three plants disturbed the ecosystem. The flora of this surveyed area belongs to the south-coast province among floral provinces of the Korean Peninsula. Our results provide basic data on vascular plants flora, plant species diversity, and distributional changes.

• Journal of Global Scholars of Marketing Science
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• v.14
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• pp.193-212
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• 2004

This study attempted to provide preliminary information for retailers to identify viable entertainment elements and to select and develop the optimal mix of entertainment elements for target consumer groups. The study examined consumer responses to various retail entertainment elements and analyzed differences in responses by consumer characteristics. The index of retail entertainment elements was developed with 49 items including entertainment facilities, dining facilities, retail, service facilities, store atmosphere, and marketing mix. The results from respondents' perceived excitement and visit intention for each entertainment element generally showed higher responses to basic marketing mix and store atmosphere elements rather than to entertainment and dining facilities. There were significant differences in responses by gender and age. The results imply that selection and application of retail entertainment elements need to consider target consumer characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.5
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• pp.731-735
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• 1994

The aims of this study are conducted to investigate the effect of pretreatment with Achatina fucica extract (AFE) in streptozotocin (STZ)-induced diabetic rats. Serum glucose, total lipid and triglyceride levels of administration group of AE in diabetic rats induced by STZ were significant high levels than that of control group. However, glucose, triglyceride and lipid levels were significant lower level in group of pretreatment with AFE and Atheroslerotic index decreased in the group of treatment of AFE when those levels compared with that of STZ-treated group. Serum lipase activity was inhibited in the control group STZ induced diabetic rats, in contrast lipase activity increased in the group of AFE administration. These results suggested that AFE may use to prevent the diabetes mellitus induced by STZ.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.3
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• pp.87-96
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• 2018

Objectives The purpose of this study is to provide more whiplash injury-specific measurement tools for Korean patients by measuring the validity and reliability of Korean version of Whiplash Disability Questionnaire (WDQ). Methods Bilingual clinicians translated the original WDQ into Korean. After consensus conference between researchers, it was back-translated into English. The pre-final version was completed and administered to 71 hospitalized patients diagnosed with whiplash injury. Validity was evaluated by concurrent validity. Reliability was assessed using Cronbach's ${\alpha}$ and intraclass correlation coefficient. Results The Korean WDQ showed good reliability with high internal consistency and intra-class correlation coefficient (Cronbach's ${\alpha}=0.96$, intraclass correlation coefficient [ICC]=0.82). Concurrent validity demonstrated positive correlations between Neck Disability Index, 36-Item Short Form Health Survey and WDQ. Conclusions The Korean version of WDQ is a valid and reliable tool for use as a measurement of whiplash injury in Korean patients, and it will be a very useful evaluation tool for both clinicians and researchers.

• Journal of The Korean Association For Science Education
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• v.31 no.5
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• pp.709-719
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• 2011

The purpose of this study was to identify the differences in classification skills shown in classification activities between the gifted and regular students in elementary schools. The subjects for the research consisted of six gifted students in an institute for the gifted for science annexed to P school district in Gangwon-do and 6 students at B and M general elementary schools. Results were as follows: The time taken for classification activities of the gifted was shorter than regular regardless of subjects for classifying. The number of standards for classifying for the gifted was more than regular students. Coefficient for measuring classification skills of the gifted was higher than regulars regardless of age. Consequently, there was a difference in the time taken for classifying and generating the number of standards and in a numerical index of classification activities performed at science classes between the science gifted and the regular students.

• KSBB Journal
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• v.23 no.5
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• pp.381-386
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• 2008

Lipophilic ammonia is toxic gas and can easily diffuse across cell membranes. Excess ammonia is implicated in the pathogenesis of several metabolic disorders including hepatic encephalopathy and may result in the death. The purpose of this study was to clarify the inhibition effect of metronidazole on liver cell damage due to ammonia in human Hep G2 cell and rat hepatocytes. The effects of metronidazole were studied in ammonium chloride treated human Hep G2 cell (75 mM) and rat hepatocyte (100 mM) following $0.1{\mu}M$ metronidazole treatment. In MTZ+AC group, cell viabilities increased prominently and LDH activities decreased over 25% than AC group. Furthermore, ammonia level according to ammonium chloride treatment reduced over 30% and lipid peroxidation as an index of cell membrane damage decreased more than twice. By comparison with control, catalase activity showed more than 30% reduction in AC group while less than 10% reduction in MTZ+AC group, respectively. In addition, MTZ+AC group showed the similar cell structure as control in cell morphology study by using light microscope, and represented fluorescent intensity decrement compared with AC group in fluorescent microscopic study with avidin-TRITC fluorescent dye. And cleaved PARP expression due to ammonia reduced twofold or more in MTZ+AC group. As the results suggest, metronidazole may protect the liver cell by inhibiting cell damages due to ammonia and be used for an effective antagonist of ammonia in hyperammonemia.

• The Korean Journal of Community Living Science
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• v.19 no.1
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• pp.87-99
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• 2008

The purpose of this study was to examine the effects of child rearing behavior and child rearing involvement on elementary school children's stress. The subjects were 201 children selected from 2 elementary schools and their parents. Data was collected using the children's stress index, the child rearing behavior questionnaire, and the child rearing involvement questionnaire, and was statistically analyzed using t-test, one-way ANOVA (Duncan test), correlation analysis and multiple regression analysis. The study showed that there were some significant differences in children's stress according to the child's gender, grade, and scholastic achievement. Correlation analysis indicated that the child's stress and the mother's child rearing behavior had significant correlation, especially the warmth acceptance behavior of the mother indicated negative high correlation. Also, the child's stress and father's child rearing behavior had significant correlation, especially the rejection restriction behavior of the father indicated positive high correlation. Correlation analysis indicated that the child's stress and the mother's child rearing involvement had significant correlation, especially the family activities involvement of the mother indicated negative high correlation. As well, the child's stress and the father's child rearing involvement had significant correlation, especially the day to day guidance involvement of the father indicated negative high correlation. It was also found that rejection restriction behavior of the father, permissiveness non-intervention behavior of the father, day to day guidance involvement of the father, family activities involvement of the father, and warmth acceptance behavior of the mother were all significant predictors of the elementary school child's stress.