• The Korean Journal of Ecology
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• v.22 no.1
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• pp.1-6
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• 1999

The author studied the soil microarthropoda's fauna, vertical distribution, seasonal fluctuation, and the relationship between the number of soil microarthropoda and environmental factor(pH) in survey area. 3949 soil microarthropoda were collected in survey area. They included Arachnida(48.6%), Collembola(23.5%), Hymenoptera(l9.9%), and Isoptera, etc. Fresh length was the longest(1l3.6 mm) in broad-leaf forest on Mt. Chilgap which is non-industrial complex area, and the shortest(46.8 mm) in pine forest at Yochon industrial complex. The population density of soil microarthropoda was the highest in summer and the lowest in winter. The number of soil microarthropoda was higher in Mt. Keryong and Chilgap, non-industrial complex area, than Yochon and Daesan, industrial complex area. The number of soil microarthropoda increased from spring to summer and decreased from autumn to winter. Vertically, soil microarthropoda were more abundant in the second layer subsoil(0∼5 cm) in spring, in the first layer(5∼10 cm) in summer and autumn, and in the third layer(0∼15 cm) in winter. Diversity index was higher in non-industrial area(1.02) than industrial complex area(0.73). Biodiversity index was the highest in the second soil layer, in pine forest on Mt. Keryong(l.60) and the lowest in the third soil layer, in broad leaf-forest, at Daesan industrial complex(0.24).

• Journal of Korea Water Resources Association
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• v.39 no.12 s.173
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• pp.997-1012
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• 2006

We have presented a nonparametric stochastic approach for the SOI(Southern Oscillation Index) series that used nonlinear methodology called Nonlinear AutoRegressive(NAR) based on conditional kernel density function and CAFPE(Corrected Asymptotic Final Prediction Error) lag selection. The fitted linear AR model represents heteroscedasticity, and besides, a BDS(Brock - Dechert - Sheinkman) statistics is rejected. Hence, we applied NAR model to the SOI series. We can identify the lags 1, 2 and 4 are appropriate one, and estimated conditional mean function. There is no autocorrelation of residuals in the Portmanteau Test. However, the null hypothesis of normality and no heteroscedasticity is rejected in the Jarque-Bera Test and ARCH-LM Test, respectively. Moreover, the lag selection for conditional standard deviation function with CAFPE provides lags 3, 8 and 9. As the results of conditional standard deviation analysis, all I.I.D assumptions of the residuals are accepted. Particularly, the BDS statistics is accepted at the 95% and 99% significance level. Finally, we split the SOI set into a sample for estimating themodel and a sample for out-of-sample prediction, that is, we conduct the one-step ahead forecasts for the last 97 values (15%). The NAR model shows a MSEP of 0.5464 that is 7% lower than those of the linear model. Hence, the relevance of the NAR model may be proved in these results, and the nonparametric NAR model is encouraging rather than a linear one to reflect the nonlinearity of SOI series.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1327-1335
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• 2017

This study was carried out to determine the effect of cacao bean addition on the physicochemical properties of extruded rice flour. Rice-based cacao beans (0, 20, 40, 60%) were extruded at a die temperature of $130^{\circ}C$, screw speed of 200 rpm, and moisture content of 25%. As the content of cacao beans increased from 20% to 60%, expansion index decreased, while piece density and specific length increased. The water soluble index and water absorption index of the extrudate increased through extrusion cooking. Lightness decreased as cacao bean content increased while redness increased. As the content of cacao beans increased, paste viscosity decreased. Cold peak viscosity was observed in all extrudates of raw roasted cacao beans. ${\alpha},{\alpha}$-Diphenyl-${\beta}$-picrylhydrazyl (DPPH) radical-scavenging activity increased upon extrusion and cacao bean addition. As content of cacao beans increased, non-roasted cacao beans had higher total phenolic contents than roasted cacao beans. This study showed that addition of cacao beans to extruded rice snack improved antioxidant activity.

• Journal of The Geomorphological Association of Korea
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• v.15 no.2
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• pp.85-94
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• 2008

This study is to construe spatio-temporal characteristics of temperature in cities and changes of climatical regions in analyzing a change of Korea Peninsular climate. We used daily mean air temperature data which was collected in South and North Korea for the past 34 years from 1974 to 2007. We created temperature map of 500m resolution using Inverse Distance Weight in application with adiabatic lapse rate per month in linear relation with height and temperature. In the urbanization area, the data analyzed population in comparison with temperature changes by the year. An annual rising rate of temperature was calculated $0.0056^{\circ}C$, and the temperature was increased $2.14^{\circ}C$ from 1974 to 2107. The south climate region in Korea by the Warmth index was expanded to the middle climate region by the latitude after 1990s. A rise of urban area in mean temperature was $0.5-1.2^{\circ}C$, Seoul, metropolitan and cities which were high density of urbanization and industrialization with the population increase between 1980s and 1990s. In case of North Korea, Cities were Pyeongyang, Anju, Gaecheon, Hesan. A rise in cities areas in mean temperature has influence on vegetation, especially secondary growth such as winter buds of pine trees appears built-up area and outskirts in late Autumn. Finally, nowaday we confront diverse natural events over climatical changes, We need a long-term research to survey and analyze an index on the climatical changes to present a systematic approach and solution in the future.

• Korean Journal of Remote Sensing
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• v.36 no.6_2
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• pp.1605-1613
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• 2020

The tidal channel is a coastal sedimentary terrain that plays the most important role in the formation and development of tidal flats, and is considered a very important index for understanding and distribution of tidal flat sedimentation/erosion terrain. The purpose of this study is to understand the changes in tidal channels by a period after the opening of the floodgate of the seawall in the reclaimed land of Sihwa Lake using KOMPSAT high-resolution multispectral satellite image data and to evaluate the applicability and efficiency of high-resolution satellite images. KOMPSAT 2 and 3 images were used for extraction of the tidal channels' lineaments in 2009, 2014, and 2019 and were applied to supervised classification method based on Principal Component Analysis (PCA), Artificial Neural Net (ANN), Matched Filtering (MF), and Spectral Angle Mapper (SAM) and band ratio techniques using Normalized Difference Water Index (NDWI) and MF/SAM. For verification, a numerical map of the National Geographic Information Service and Landsat 7 ETM+ image data were utilized. As a result, KOMPSAT data showed great agreement with the verification data compared to the Landsat 7 images for detecting a direction and distribution pattern of the tidal channels. However, it has been confirmed that there will be limitations in identifying the distribution of tidal channels' density and providing meaningful information related to the development of the sedimentary process. This research is expected to present the possibility of utilizing KOMPSAT image-based high-resolution remote exploration as a way of responding to domestic intertidal environmental issues, and to be used as basic research for providing multi-platform-image-based convergent thematic maps and topics.

• Journal of the Korean Geosynthetics Society
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• v.21 no.4
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• pp.1-12
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• 2022

Generally, the plate load test and the field density test are conducted for compaction quality control in earthwork, and then additional analysis. Recently developed that the DCPT (Dynamic Cone Penetration Test) equipment for smart compaction quality control its the system are able to get location and real-time information about worker history management. The IoT-based the DCPT system improved the time-cost in the field compared traditional test, and the functions recording and storage of the DPI (Dynamic Cone Penetration Index) were automated. This paper describes using these DCPT equipment on in-situ and compared to the standards of the DCPT, and the compaction trend had be confirmed with DPI as the field test data. As a result, the DPI of the final compaction decreased by 1.4 times compared to the initial compaction, confirming the increase in the compaction strength of the subgrade compaction layer 10 to 14 cm deep from the surface. A trend of increasing compaction strength was observed. This showed a tendency to increase the compaction strength of the target DPI proposed by MnDOT and the results of the existing plate load test, but there was a difference in the increase rate. Therefore, additional studies are needed on domestic compaction materials and laboratory conditions for target DPI and correlation studies with the plate load tests. If this is reflected, it is suggested that DCPT will be widely used as smart construction equipment in earthworks.

• Journal of Korean Society of Forest Science
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• v.111 no.3
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• pp.374-384
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• 2022

There is an increasing demand for Tetradium daniellii seedlings due to their uses as alternative energy, for ecological restoration, and as a honey plant. This study was conducted to determine the optimum container for superior seedling production of T. daniellii. Experiments were performed using five plastic container types (500, 350, 320, 300, and 250 ml) for forestry facility cultivation. The height and root collar diameter growth of T. daniellii seedlings were significantly high in the 350-ml container. High growth appeared primarily in the container with a larger cavity volume and lower growing density. Root development was most active in full sunlight. The maximum dry matter production was observed in the 350-ml container, which was similar to the results of height and root collar diameter growth. QI, an index showing the quality of a seedling, was maximum at 0.97 in the 350-ml container. In conclusion, the 350-ml container is optimum for superior seedling production of T. daniellii.

• Korean Journal of Environment and Ecology
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• v.37 no.6
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• pp.450-463
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• 2023

The objective of this study is to derive the core habitat of the Kirengeshoma koreana Nakai utilizing Habitat Suitability Index (HSI) and Maximum Entropy (MaxEnt) models. Expert-based models have been criticized for their subjective criteria, while statistical models face difficulties in on-site validation and integration of expert opinions. To address these limitations, both models were employed, and their outcomes were overlaid to derive the core habitat. Five variables were identified through a comprehensive literature review and spatial analysis based on appearance coordinates. The environmental variables encompass vegetation zone, forest type, crown density, annual precipitation, and effective soil depth. Through surveys involving six experts, importance rankings and SI (Suitability Index) scores were established for each variable, subsequently facilitating the creation of an HSI map. Using the same variables, the MaxEnt model was also executed, resulting in a corresponding map, which was merged to construct the definitive core habitat map. Out of 16 observed locations of K. koreana, 15 were situated within the identified core habitat. Furthermore, an area historically known to host K. koreana but not verified in the present, Mt. Yeongchwi, was found to lack a core habitat. These findings suggest that the developed models exhibit a high degree of accuracy and effectively reflect the current ecological landscape.

• Journal of Nutrition and Health
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• v.57 no.1
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• pp.105-119
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• 2024

Purpose: The atherogenic index of plasma (AIP) is gaining recognition as a superior predictor of coronary artery disease. This study examined the relationship between the AIP and the intake of various food groups in Korean adults, using the baseline data from the Korean Genome and Epidemiology Study-The Health Examinees (KoGES-HEXA) study. Methods: This study included 133,381 adults (46,288 men, 87,093 women) who completed the nutrition survey and biochemical tests of the KoGES-HEXA study. The AIP was calculated as the log (triglycerides/high-density lipoprotein-cholesterol) and was divided into quintiles according to sex for further analysis. Data on food group intake were obtained using the semi-quantitative food frequency questionnaire, and daily food group intake (g/d) was evaluated for each individual. The association between the food group intake and the AIP was examined using the linear regression analysis after adjusting for the confounding variables. Results: In this study population, there was a positive correlation between energy intake and the AIP in men whereas an inverse assocation was shown in women (p < 0.001). In women, a rise in the AIP significantly correlated with an increased percentage of energy intake derived from carbohydrates but decreased percentages of energy from protein and fat (p < 0.001). In men and women, the consumption of grains and kimchi/pickles increased as the AIP rose, while the intake of legumes, nuts, meat and its products, eggs, fish, and milk and dairy products decreased. Among men, individuals in the highest AIP group showed higher intake of wheat products than those in the lowest group of the AIP. In women, the AIP was inversely correlated with potatoes and beverages consumption. Conclusion: This study highlights the importance of a balanced diet, including various protein sources, milk and dairy products, legumes, and nuts, for preventing cardiovascular diseases. Further research into sex-specific dietary patterns is essential for tailoring appropriate dietary recommendations.

• Korean journal of food and cookery science
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• v.20 no.5
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• pp.468-479
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• 2004

This study was conducted to investigate factors affecting the bone density of university students in the Seoul area. Data for food habits, and dietary and health-related behavior was obtained by self-administered questionnaires. BQI (bone quality index) of the subjects was measured by a Quantitative Ultrasound (QUS). The results are summarized as follows. The average height, weight, BMI and osteopenia percentage were 175.4cm, 69.3kg, 22.5 and 15.6% for male students, and 161.5cm, 55.9kg, 21.7 and 34.1%, for female students, respectively. The mean BQI of the subjects was 110.25 (range 60.7 ～ 176.8) in male students and 90.64 (range 52.9 ～ 137.5) in female students. Height and weight were significantly related with BQI in the female group but the relationship with BMI was not significantly related with bone density in either group. BQI was positively affected by nutrition supplement in the male student group. One-side eating, diet, and intake of milk and instant food were not significantly related with BQI in males or females. The results of this study revealed that desirable food habits, dietary behavior and health-related lifestyle may have a beneficial effect on bone density. There should be established a practically and systematically organized nutritional education on optimum body weight, good eating habits, weight bearing exercise and intakes of good quality nutrient for higher bone density level.