• Journal of Ecology and Environment
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• v.43 no.3
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• pp.289-296
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• 2019

We investigated the mortality and the oxidative damages of Deschampsia antarctica in response to waterlogging stress. In field, we compared the changes in the density of D. antarctica tuft at the two different sites over 3 years. The soil water content at site 2 was 6-fold higher than that of site 1, and the density of D. antarctica tuft decreased significantly by 55.4% at site 2 for 3 years, but there was no significant change at site 1. Experimental results in growth chamber showed that the $H_2O_2$ and malondialdehyde content increased under root-flooding treatment (hypoxic conditions-deficiency of $O_2$), but any significant change was not perceptible under the shoot-flooding treatment (anoxic condition-absence of $O_2$). However, total chlorophyll, soluble sugar, protein content, and phenolic compound decreased under the shoot-flooding treatment. In addition, the catalase activity increased significantly on the 1st day of flooding. These results indicate that hypoxic conditions may lead to the overproduction of reactive oxygen species, and anoxic conditions can deplete primary metabolites such as sugars and protein in the leaf tissues of D. antarctica. Under present warming trend in Antarctic Peninsula, D. antarctica tuft growing near the shoreline might more frequently experience flooding due to glacier melting and inundation of seawater, which can enhance the risk of this plant mortality.

• Journal of Soil and Groundwater Environment
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• v.26 no.1
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• pp.24-33
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• 2021

Analysis of long term affecting factors on water quality items of gas emission form (BOD, COD) and leachate emission form (T-N, non-bio-degradable COD (NBDCOD)) was performed for the SUDOKWON 1st Landfill Site (LS1) and 2nd Landfill Site (LS2). As landfill gas was generated, BOD and COD decreased from 6,887 and 20,025 mg/L in 1993 to 49.5 and 670.2 mg/L in 2019, respectively. TN and NBDCOD increased with waste decomposition but gradually decreased after landfill closure because of the precipitation infiltration effect. Due to the drastic decline of carbon in the leachate, the BOD/TN ratios of LS1 and LS2 declined from 13.0 and 17.0 during early stage of the landfill to 0.07 and 0.16 in 2019, respectively; LS2 and NBDCOD/COD increased from 0.25 to 0.65 during the same period. These conditions caused carbon deficiency in denitrification treatment and a chemical post-treatment request for NBDCOD. The different behaviors of gas emission and leachate emission items suggest the necessity of different strategic approaches in the long term perspective.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.75-80
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• 2000

Evaluation method of seismic performance has mainly used elastic spectrum analysis. This method has simplicity of analysis but deficiency of accuracy. And evaluation method of seismic performance using inelastic dynamic analysis reflects accurately inelasticity of material but hardly reflects site effects. This study suggested evaluation scheme of seismic performance for bridge structure using capacity spectrum method applied inelastic static analysis and standard design response spectrum of Korea Standard Specification for Highway Bridge. Two results, capacity spectrum method and inelastic dynamic analysis method, are very similar. As a result, this study appropriately supply both simplicity of analysis and accuracy of result.

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.777-778
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• 2009

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.1
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• pp.76-81
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• 2014

The aim of this study was to build the diagnosis criteria of Qi deficiency using distribution of sum of 11 items for Qi deficiency in stroke patients. Between September 2006 and December 2010, 2,994 patients from 11 Korean medical hospitals were asked to complete the Korean Standard Pattern Identification for Stroke (K-SPI-Stroke) questionnaire as a part of project 'Fundamental study for the standardization and objectification of pattern identification in traditional Korean medicine for stroke (SOPI-Stroke). Each patient was independently diagnosed by two experts (traditional Korean medicine physicians) from the same site according to one of five patterns. 2,994 patients were divided modeling and testing in 70:30 ratio by stratification of pattern identification. We calculated the sensitivity, specificity, accuracy and odds ratio (OR) using distribution of sum of 11 items (signs and symptoms) for Qi deficiency. More than four from 11 items of Qi deficiency in modeling dataset, sensitivity, specificity, accuracy and OR was 70.07%, 74.94%, 73.92% and 7.00, respectively. In testing dataset, 78.31%, 73.45%, 74.47% and 9.98, respectively. Although this values are not high, after values of sensitivity, specificity, accuracy and OR should be more than current value, and then we should be able to suggest as objective diagnosing criteria.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.1
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• pp.141-158
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• 2022

Currently, there are some aptitude test systems for older drivers in Korea. However, there are no methods and systems to evaluate the real driving ability for older drivers based on filed driving test. This study was conducted to investigate the availability to use the driving course test used for driving license for identifying difference in driving ability of older and non-older drivers. For the research purpose, filed experiments were conducted using the real driving course test site and evaluation times used in the field. In particular, driving behavior data that obtained from the experiments for two driver groups, older and non-older drivers, were analyzed and compared. From several statistical analyses of driving ability and vision and cognitive ability, it was found that the currently used driving course test site and evaluation times were not appropriated to identify driving ability deficiency of older drivers. To solve the problem, this study developed five evaluation items to identify driving ability deficiency of older drivers using the currently used driving course test site. It was also found that the developed five evaluation items have statistically significant correlation with vision and cognitive ability.

• Journal of Integrative Natural Science
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• v.8 no.4
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• pp.267-272
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• 2015

Galactosemia is a potentially lethal disorder caused by the deficiency of the enzyme galactose-1-phosphate uridyltransferase (GALT) within the Leloir pathway. Galactokinase (GALK) is the enzyme in Leloir pathway which converts ${\alpha}$-D galactose to galactose 1-phosphate. The elevated level of galactose-1-phosphate, the product of GALK plays a major role in Galactosemia. Therefore the inhibition of GALK is a novel therapy for this disorder. Hence in the present study, we performed molecular docking of twenty inhibitors with different activity against galactokinase into the active site of galactokinase enzyme. The binding mode of these inhibitors was obtained using Surflex dock program interfaced in Sybyl-X2.0. The residues such as SER141, TYR109, ARG105, ARG228, TYR106, GLY346, GLY136, ASP86, ASP186 and SER142 found to interact with inhibitors.

• Journal of Sensor Science and Technology
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• v.29 no.1
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• pp.7-13
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• 2020

Dielectric capacitors are integral components in electronic devices that protect the electric circuit by providing modulated steady voltage. Explosive growth of the electric automobile market has resulted in an increasing demand for dielectric capacitors that can operate at temperatures as high as 400 ℃. To surpass the operation temperature limit of currently available commercial capacitors that operate in temperatures up to 125 ℃, Bi_1/2Na_1/2TiO₃ (BNT), which has a large temperature-insensitive dielectric response with a maximum dielectric permittivity temperature of 300 ℃, was selected. By introducing an intentional A-site cation deficiency and post-heat treatment, we successfully manage to control the dielectric properties of BNT to use it for high-temperature applications. The key feature of this new BNT is remarkable reduction in dielectric loss (0.36 to 0.018) at high temperature (300 ℃). Structural, dielectric, and electrical properties of this newly developed BNT were systematically investigated to understand the underlying mechanism.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.2
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• pp.184-191
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• 2014

In the mandibular posterior molar area, ridge deficiency is an unfortunate obstacle in the field of implant dentistry. Many techniques are available to rebuild the deficient ridge. Selection and necessity of these techniques are associated with significant morbidity and often require a second surgical site. With the advent of guided bone regeneration (GBR), one may now graft the deficient ridge with decreased morbidity and without a second surgical site. In this case, guided bone regeneration procedures were performed with a combination of allograft, xenograft, and alloplast, excepting autogerous bone at severe defected mandibular alveolar ridge and then placed to the implant successfully. We report that implant placement were good in two cases.

• Agricultural and Biosystems Engineering
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• v.7 no.1
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• pp.18-26
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• 2006

In-field site-specific nitrogen (N) management increases crop yield, reduces N application to minimize the risk of nitrate contamination of ground water, and thus reduces farming cost. Real-time N sensing and fertilization is required for efficient N management. An 'on-the-go' site-specific N management system was developed and evaluated for the supplemental N application to com (Zea mays L.). This real-time N sensing and fertilization system monitored and assessed N fertilization needs using a vision-based spectral sensor and controlled the appropriate variable N rate according to N deficiency level estimated from spectral signature of crop canopies. Sensor inputs included ambient illumination, camera parameters, and image histogram of three spectral regions (red, green, and near-infrared). The real-time sensor-based supplemental N treatment improved crop N status and increased yield over most plots. The largest yield increase was achieved in plots with low initial N treatment combined with supplemental variable-rate application. Yield data for plots where N was applied the latest in the season resulted in a reduced impact on supplemental N. For plots with no supplemental N application, yield increased gradually with initial N treatment, but any N application more than 101 kg/ha had minimal impact on yield.