• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.73-76
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• 1995

In this study, the slab waveguide was fabricated using potassium-nitride(KNO$_3$) or silver-nitride (AgNO$_3$) molten sources by ion-exchange process. The effective refractive indices of waveguide were measured by Prism-Coupling method. and The characteristics of waveguide(mode dispersion, effective diffusion depth. surface refractive index, diffusion coefficient, and refractive index profile etc,) were investigated by WKB method, In the case of potassium ion-exchange, the computer calculation showed that the refractive index profile of waveguide followed Gaussian function, the surface refractive index increased with ion-exchange time and the effective diffusion depth increased a little as ion-exchange time increased, while the surface refractive index of silver ion-exchanged waveguide decreased with ion-exchange time because of the ion depletion on the surface of waveguide, and the effective diffusion depth seriously with ion-exchange tim. Double ion-exchanged waveguide was fabricated by performing silver ion-exchange after potassium ion-exchange. Double ion-exchanged waveguide had a tight mode binding force since the surface refractive index was larger than single step ion-exchanged waveguide.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.53-61
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• 2013

Objectives: It is certain that Radioactive iodine thyroid uptake(RAIU) rate should be measured with the standard counts considering the thyroid gland depth in enlarged thyroid patients for the variation from geometric factors. The purpose of this paper is to consider the effects of geometric factors according to detector to source distance and the effective thyroid depth on RAIU rate with experiment test. Materials and Methods: I-131 370 kBq ($10{\mu}Ci$) point source was measured by Captus-3000 thyroid uptake system (Capintec, NJ, USA) with a change Detector-Source Distance from 20 cm to 30 cm at an interval of 1 cm. And we changed the Neck phantom surface-Source Depth in the phantom with 1 cm, 2 cm, 5 cm using the neck phantom in order to reproduce the effective thyroid depth. Results: Every experimental group follows power curve as inverse square curve ($$R2{\geq_-}0.915$$). The average count rates in the case not using a phantom and the every case applied the effective thyroid depth using a phantom was not identical each other. There was significant fluctuations upon the effective thyroid depths applied the effective thyroid depth above 1 cm in $364.4 keV{\pm}10%$ energy ROI (p<0.01). There was not significant difference between the count rates of 1 cm and 2 cm in $364.4keV{\pm}20%$ and $637.1keV{\pm}6.2%$ (p=0.354, p=0.397). In assumed RAIU rate from regression equation, $364.4keV{\pm}20%$ was lower difference than $364.4keV{\pm}10%$ as 6.42% and 5.09% per 1 cm. Every change of count rate upon depth appears decreased line on Linear Regression, but the case of $284.3keV{\pm}10%$ increased only. And also, The graphs of coefficient of variation upon depth increased as straight line on every experimental group. Conclusion: The result appears that application of $364.4keV{\pm}20%$ energy ROI is more suitable for reducing error from the effective thyroid depth. And also, we can estimate the error of 20 cm should be highly reduced than 30 cm for Inverse Square Law. Therefore, If there is not information of the thyroid depth, it is considered that the error from thyroid depth can reduce through set up energy ROIs for $364.4keV{\pm}20%$, and increase Detector-Source Distances.

• Journal of the Korean institute of surface engineering
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• v.44 no.5
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• pp.207-212
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• 2011

In this study, the change in diffusion coefficient and wear characteristic with depth in the carbonitriding layer of SCM415 steel was discussed. To determine the diffusion coefficient, depth profile of carbon was measured from the surface using the Glow Discharge Spectrometer. In otherwise, measurements of carbide fraction, micro vickers hardness of surface and observation of microstructure have been implemented through the SEM image. $Fe_3$(C,N) layer and effective depth were increased as the time for carbonitriding takes longer. According to wear experiment, the results showed that wear resistance was improved by $Fe_3$(C,N) layer and effective depth.

• Journal of The Korean Astronomical Society
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• v.39 no.4
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• pp.125-128
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• 2006

In order to determine the precise effective temperature and surface gravity of warm stars, all synthetic spectral lines in the wavelength range of $4000-5700{\AA}$ with T=6000-7750 K, and log g=3.5, 4.0, and 4.5 for [M/H]=0.0, $V_{rot}$=10 km $s^{-1}$, and $V_{tubl}$=2 km $s^{-1}$ were calculated using the SYNSPEC package(Hubeny, et al., 1995) and the Kurucz(1995) model. Then, the depth-ratios for all line pairs were investigated and we selected two and six depth-ratios appropriate for the surface gravity and temperature indicators, respectively. We plotted six grids with X- and Y-axes for the depth-ratios of surface gravity and temperature, respectively, for the simultaneous estimation of these two atmospheric parameters. This method was applied to the spectum of $\delta$ Scu for the determination of its temperature and surface gravity simultaneously.

• Journal of the Semiconductor & Display Technology
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• v.10 no.3
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• pp.99-103
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• 2011

The stereoscopic vision system is the algorithm to obtain the depth of target object of stereo vision image. This paper presents an efficient disparity matching method using blue edge filter and graph cut algorithm. We do recommend the use of the simple sobel edge operator. The application of B band sobel edge operator over image demonstrates result with somewhat noisy (distinct border). The basic technique is to construct a specialized graph for the energy function to be minimized such that the minimum cut on the graph also minimizes the energy (either globally or locally). This method has the advantage of saving a lot of data. We propose a preprocessing effective stereo matching method based on sobel algorithm which uses blue edge information and the graph cut, we could obtain effective depth map.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.659-666
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• 2004

Dynamic compaction has evolved as an acceptable method of site improvement by treating poor soils in situ. The method is often an economical alternative for utilizing shallow foundations and preparing subgrades for construction when compared with conventional solutions. In general, the installation purpose of dynamic compaction are to increase bearing capacity and decrease differential settlement within a specified depth of improvement. This method involves the s systematically dropping large weights onto the ground surface to compact the underlying ground. The weights used on dynamic compaction projects have been typically constructed of steel plates, sand or concrete filled steel shells, and reinforced concrete. Typically, weights range from 5-20 ton and base configurations are, circular or octagonal. In this study, the effective depth of improvement is evaluated based on the numerical analysis code, the dynamic analysis of FLAC-3D program, in order to analyze the influence parameters ; ground conditions, maximum applied load and the area of compaction plate.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.2
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• pp.235-247
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• 2006

Aerosol indirect radiative forcing of climate change is considered the most uncertain forcing of climate change over the industrial period, despite numerous studies demonstrating such modification of cloud properties and several studies quantifying resulting changes in shortwave radiative fluxes. Detection of this effect is made difficult by the large inherent variability in cloud liquid water path (LWP): the dominant controlling influence of LWP on optical depth and albedo masks any aerosol influences. Here we have used ground-based remote sensing of cloud optical depth (${\tau}_c$) by narrowband radiometry and LWP by microwave radiometry to determine the dependence of optical depth on LWP, thereby permitting examination of aerosol influence. The method is limited to complete overcast conditions with liquid-phase single layer clouds, as determined mainly by millimeter wave cloud radar. The results demonstrate substantial (factor of 2) day-to-day variation in cloud drop effective radius at the ARM Southern Great Plains site that is weakly associated with variation in aerosol loading as characterized by light-scattering coefficient at the surface. The substantial scatter suggests the importance of meteorological influences on cloud drop size as well, which should be analyzed in the further intensive studies. Meanwhile, it is notable that the decrease in cloud drop effective radius results in marked increase in cloud albedo.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.6
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• pp.247-255
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• 2022

In this paper, a bending test was conducted on beams with two lap splice details when the effective depth of tensile high strength headed bars overlapped is the same and different. Through bending test, the lap splice performance of the high-strength headed bars was evaluated, and the applicability of the KDS-2021 design formula was evaluated. In the LS specimens with lap splice details where the high strength bars had the same effective depth, all specimens with 1.3 times or more of the development length of the KDS-2021 equation and 1 times or more of the ACI318-19 had the flexural failure mode after the ductile behavior to ensure sufficient lap splice performance. For specimens with details of lap joints between headed bars with different effective depth, when lap splice length is calculated by the KDS-2021 formula, the flexural stress may be transmitted so that the flexural strength at the cross section with the large effective depth and the cross section with the small effective depth becomes similar.

• Journal of the Korean Geosynthetics Society
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• v.22 no.2
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• pp.1-12
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• 2023

Research on the causes of landslides and prediction of vulnerable areas is being conducted globally. This study aims to predict the effective soil depth, a critical element in analyzing and forecasting landslide disasters, using topographic information. Topographic data from various institutions were collected and assigned as attribute information to a 100 m × 100 m grid, which was then reduced through data grading. The study predicted effective soil depth for two cases: three depths (shallow, normal, deep) and five depths (very shallow, shallow, normal, deep, very deep). Three classification models, including K-Nearest Neighbor, Random Forest, and Deep Artificial Neural Network, were used, and their performance was evaluated by calculating accuracy, precision, recall, and F1-score. Results showed that the performance was in the high 50% to early 70% range, with the accuracy of the three classification criteria being about 5% higher than the five criteria. Although the grading criteria and classification model's performance presented in this study are still insufficient, the application of the classification model is possible in predicting the effective soil depth. This study suggests the possibility of predicting more reliable values than the current effective soil depth, which assumes a large area uniformly.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.555-558
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• 2001

Carbonation of concrete decreases durability of RC structures due to failure of passive film of rebar. Therefore, expecting carbonation depth is a governing parameter of service life prediction for RC structures. This study attempt to estimate carbonation depth quantitatively by using equivalent effective diffusion coefficient of $CO_2$.