• Geotechnical Engineering
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• v.12 no.6
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• pp.79-86
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• 1996

This study develops a new method for interpreting the yield load from load tests on drilled shaft foundations ended on general soils, which is defined as a point where the maximum curvature on the hyperbolic-approximated load-settlement curve occurs. How ever, the point of maximum curvature is a variable depending on the units and scales of the load and settlement. Therefore, to obtain a unique maximum curvature point, both the load and settlement must be normalized by proper parameters, respectively, and be expressed on the same scaled arses(1:1). Normalization has been processed so that the yield load by the new interpretation is to be close to the average of yield loads interpreted by other methods investigated in this study. The quantitative comparison between the new criterion and other conventitonal methods is presented.

• Journal of the Korea Computer Industry Society
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• v.9 no.1
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• pp.21-28
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• 2008

In this paper, the edge parameters were drawn from speaking image around lip and effective automatic lip reading system to recognize the Korean 'a/e/i/o/u' 5 owels were constructed using the parameter. Speaking images around lip were divided into $5{\times}5$ pane. In each pane the number of digital edge element using Sobel operator were evaluated. The observational error between samples was corrected by using normalization method and the normalized value is used for parameter In the experiment to convince the strength of parameter, 50 normal persons were sampled. The images of 10 persons were analyzed and the images of another 40 persons were experimented for recognition. 500 data are gathered and analyzed. Based on this analysis, the neural net system is constructed and the recognition experiments are performed for 400 data. The neural net system gave the best recognition result of 91.1%.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.4
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• pp.235-243
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• 2016

Korea is part of a region of low to moderate seismicity located inside the Eurasian plate with bedrock located at depths less than 30 m. However, the spectral acceleration obtained from site response analyses based on the geologic conditions of inland areas of the Korean peninsula are significantly different from the current Korean seismic code. Therefore, suitable site classification scheme and design response spectra based on local site conditions in the Korean peninsula are required to produce reliable estimates of earthquake ground motion. In this study, site-specific response analyses were performed at more than 300 sites with at least 100 sites at each site categories of $S_C$, $S_D$, and $S_E$ as defined in the current seismic code in Korea. The process of creating a huge database of input parameters - such as shear wave velocity profiles, normalized shear modulus reduction curves, damping curves, and input earthquake motions - for site response analyses were described. The response spectra and site coefficients obtained from site response analyses were compared with those proposed for the site categories in the current code. Problems with the current seismic design code were subsequently discussed, and the development and verifications of new site classification system and corresponding design response spectra are detailed in companion papers (II-development of new site categories and design response spectra and III-Verifications)

• Journal of Ginseng Research
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• v.44 no.3
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• pp.483-489
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• 2020

Background: Korean Red Ginseng (KRG) has been known to possess many ginsenosides. These ginsenosides are used for curing cardiovascular problems. The present study show the protective potential of KRG against doxorubicin (DOX)-induced myocardial dysfunction, by assessing electrocardiographic, hemodynamic, and biochemical parameters and histopathological findings. Methods: Animals were fed a standard chow and adjusted to their environment for 3 days before the experiments. Next, the rats were equally divided into five groups (n = 9, each group). The animals were administered with KRG (250 and 500 mg/kg) for 10 days and injected with DOX (20 mg/kg, subcutaneously, twice at a 24-h interval) on the 8th and 9th day. Electrocardiography and echocardiography were performed to study hemodynamics. Plasma levels of superoxide dismutase, catalase, glutathione peroxidase, and malondialdehyde were measured. In addition, the dose of troponin I and activity of myeloperoxidase in serum and cardiac tissue were analyzed, and the histopathological findings were evaluated using light microscopy. Results: Administration of KRG at a dose of 250 and 500 mg/kg recovered electrocardiographic changes, ejection fraction, fractional shortening, left ventricular systolic pressure, the maximal rate of change in left ventricle contraction (-dP/dt_max), and left ventricle relaxation (-dP/dt_max). In addition, KRG treatment significantly normalized the oxidative stress markers in plasma, dose dependently. In addition, the values of troponin I and myeloperoxidase were ameliorated by KRG treatment, dose dependently. And, KRG treatment showed better histopathological findings when compared with the DOX control group. Conclusion: These mean that KRG mitigates myocardial damage by modulating the hemodynamics, histopathological abnormality, and oxidative stress related to DOX-induced cardiomyopathy in rats. The results of the present study show protective effects of KRG on cardiac toxicity.

• Journal of Ginseng Research
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• v.39 no.3
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• pp.206-212
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• 2015

Background: Ginseng total saponin (GTS) contains various ginsenosides. These ginsenosides are widely used for treating cardiovascular diseases in Asian communities. The aim of this study was to study the effects of GTS on cardiac injury after global ischemia and reperfusion (I/R) in isolated guinea pig hearts. Methods: Animals were subjected to normothermic ischemia for 60 minutes, followed by 120 minutes of reperfusion. GTS significantly increased aortic flow, coronary flow, and cardiac output. Moreover, GTS significantly increased left ventricular systolic pressure and the maximal rate of contraction ($+dP/dt_{max}$) and relaxation ($-dP/dt_{max}$). In addition, GTS has been shown to ameliorate electrocardiographic changes such as the QRS complex, QT interval, and RR interval. Results: GTS significantly suppressed the biochemical parameters (i.e., lactate dehydrogenase, creatine kinase-MB fraction, and cardiac troponin I levels) and normalized the oxidative stress markers (i.e., malondialdehyde, glutathione, and nitrite). In addition, GTS also markedly inhibits the expression of interleukin-$1{\beta}$ (IL-$1{\beta}$), IL-6, and nuclear factor-${\kappa}B$, and improves the expression of IL-10 in cardiac tissue. Conclusion: These data indicate that GTS mitigates myocardial damage by modulating the biochemical and oxidative stress related to cardiac I/R injury.

• Journal of Korean Society of Forest Science
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• v.96 no.5
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• pp.591-601
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• 2007

Spatial information on forest biomass is an important factor to evaluate the capability of forest as a carbon sequestrator and is a core independent variable required to drive models which describe ecological processes such as carbon budget, hydrological budget, and energy flow. The objective of this study is to understand the relationship between satellite image and field data, and to quantitatively estimate and map the spatial distribution of forest biomass. Landsat Enhanced Thematic Mapper (ETM+) derived vegetation indices and field survey data were applied to estimate the biomass distribution of mountainous forest located in Gwangneung Experimental Forest (230 ha). Field survey data collected from the ground plots were used as the dependent variable, forest biomass, while satellite image reflectance data (Band 1~5 and Band 7), Normalized Difference Vegetation Index (NDVI), Soil-Adjusted Vegetation Index (SAVI), and RVI (Ratio Vegetation Index) were used as the independent variables. The mean and total biomass of Gwangneung catchment area were estimated to be about 229.5 ton/ha and $52.8{\times}10^3$ tons respectively. Regression analysis revealed significant relationships between the measured biomass and Landsat derived variables in both of deciduous forest ($R^2=0.76$, P < 0.05) and coniferous forest ($R^2=0.75$, P < 0.05). However, there still exist many uncertainties in the estimation of forest ecosystem parameters based on vegetation remote sensing. Developing remote sensing techniques with adequate filed survey data over a long period are expected to increase the estimation accuracy of spatial information of the forest ecosystem.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.3
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• pp.66-73
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• 2004

As a rocket propellent of hydrocarbon fuels, the characteristics of liquefied natural gas was evaluated with the viewpoint of the constituents and content, the cooling performance as a coolant, and characteristic velocity and specific impulse as parameters of the engine performance. Content of methane was a principal factor to determine the characteristics as a rocket propellant and more than 90% of it was needed as a fuel and coolant in the regenerative cooled liquid rocket engine. Some constituents of the liquefied natural gas can be frozen by the pre-cooling of the pipe lines, therefore they can be a factor disturbing the normal working of engine. In case the content of methane is around 90% in the liquefied natural gas, a normalized stoichiometric O/F mixture ratio of 0.75 is suggested for a nominal operation condition to get the maximum specific impulse and characteristic velocity.

• Journal of Welding and Joining
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• v.13 no.2
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• pp.42-52
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• 1995

In the evaluation of aging degradation on the structural materials based on the fracture mechanics, the detection and size prediction of defect are very important. Aiming at nondestructive detection and size prediction ol defect with high accuracy and resolution, therefore, an lnduced Current Focusing Potential Drop(ICFPD) technique has been developed. The principle of this technique is to induce a focusing current at an exploratory region by an induction wire flowing an alternating current(AC) that is a constant ampere and frequency. Defects are assessed with the potential drops that are measured the induced current on the surface of metallic material by the potential pick-up pins. In this study, the lCFPD technique was applied for evaluating the location and size of the surface crack and blind crack made in plate specimens, and also for detecting the defects existing in valve, a field component, that were developed by SCC etc. during the service. The results of this present study show that surface crack and blind crack are able to defect with potential drop. these cracks are distinguished with the distribution of potential drop, and the crack depths can be estimated with each normalized potential drop that are parameters estimating the depth of each type crack. In the field component, the defects estimated by experiment result correspond with those in the cutting face of the measuring point within a higher sensitivity.

• Journal of Gastric Cancer
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• v.18 no.3
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• pp.242-252
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• 2018

Purpose: Surgical resection for gastric adenocarcinoma is associated with significant post-operative morbidity and mortality. The aim of this study was to assess the prognostic significance of sarcopenia in patients undergoing resection for gastric adenocarcinoma with respect to post-operative morbidity and survival. Materials and Methods: A retrospective analysis was conducted on a cohort of consecutive patients who underwent surgical resection for gastric adenocarcinoma between 2008 and 2014. Patient demographics, radiological parameters, and pathological data were collected. OsiriX software (Pixmeo) was used to measure skeletal muscle area, which was normalized for height to calculate skeletal muscle index. Results: A total of 56 patients (41 male, 15 female; mean age, $68.4{\pm}11.9years$) met the inclusion criteria. Of these, 36% (20 of 56) of the patients were sarcopenic pre-operatively. Both sarcopenic and non-sarcopenic patient groups were equally matched with the exception of weight and body mass index (P=0.036 and 0.001, respectively). Sarcopenia was associated with a decreased overall survival (log-rank P=0.003) and was an adverse prognostic predictor of overall survival in multivariate analysis (hazard ratio, 10.915; P=0.001). Sarcopenia was a predictor of serious in-hospital complications in multivariate analysis (odds ratio, 3.508; P=0.042). Conclusions: In patients undergoing curative resection for gastric cancer, there was a statistically significant association between sarcopenia and both decreased overall survival and serious post-operative complications. The measurement and reporting of skeletal muscle index on pre-operative computed tomography should be considered.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.8
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• pp.791-797
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• 2013

This paper proposes a new way to verify the performance of an absorber lined shielded enclosure(ALSE) in accordance with CISPR25, EMC standards dedicated to testing automotive components. CISPR16 requires the use of NSA and VSWR methods to test the performance of a chamber. As for CISPR25, however, there hasn't been standardized ways to verify the performance of ALSE. This paper purports to present an improved method for the verification based on a long-wire antenna method under discussion at CISPR25 JFT. Existing discussions on a long-wire antenna method proposes that an antenna should reach 500 millimeters in length, while this paper adopts the antenna length of 1,700 millimeters. This paper also assesses the effects of matching conditions and studies problems related to methods which have been already proposed and key parameters in order to improve verification methods.