• Science of Emotion and Sensibility
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• v.7 no.4
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• pp.25-33
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• 2004

This study surveys the fabric surface properties such as mean value of the friction coefficient(MIU), mean deviation of the friction coefficient(MMD) and mean deviation of surface roughness(SMD) due to warp and weft tension differences using KES-FB system. For this purpose, fabric is designed as 5 harness Satin weave using 75d/36f warp and 100d/192f weft polyester filaments, and is woven by OmegaR rapier loom by Textec Co.Ltd and Picanol-GTXR rapier loom by Picanol Co.Ltd respectively. These grey fabrics are processed on the same dyeing and finishing processes. The fabric surface properties according to the weaving looms are analysed with warp and weft weaving tensions. And also surveyed the difference of fabric surface properties according to the fabric positions such as center and each edge of fabrics for the sensitive garment.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.5
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• pp.407-419
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• 2008

In this study, the transition Reynolds number of compressible axi-symmetric sharp cone boundary layer is predicted by using a linear stability theory and the -method. The compressible linear stability equation for sharp cone boundary layer was derived from the governing equations on the body-intrinsic axi-symmetric coordinate system. The numerical analysis code for the stability equation was developed based on a second-order accurate finite-difference method. Stability characteristics and amplification rate of two-dimensional second mode disturbance for the sharp cone boundary layer were calculated from the analysis code and the numerical code was validated by comparing the results with experimental data. Transition prediction was performed by application of the -method with N=10. From comparison with wind tunnel experiments and flight tests data, capability of the transition prediction of this study is confirmed for the sharp cone boundary layers which have an edge Mach number between 4 and 8. In addition, effect of wall cooling on the stability of disturbance in the boundary layer and transition position is investigated.

• Journal of Broadcast Engineering
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• v.16 no.6
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• pp.902-915
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• 2011

Recently in the area-based stereo matching field, Adaptive Support-Weight (ASW) method that weights matching cost adaptively according to the luminance intensity and the geometric difference shows promising matching performance. However, ASW requires more computational cost than other matching algorithms do and its real-time implementation becomes impractical. By applying Integral Histogram technique after approximating to the Bilateral filter equation, the computational time of ASW can be restricted in constant time regardless of the support window size. However, Integral Histogram technique causes loss of the matching accuracy during approximation process of the original ASW equation. In this paper, we propose a novel algorithm that maintains the ASW algorithm's matching accuracy while reducing the computational costs. In the proposed algorithm, we propose Sub-Block method that groups the pixels within the support area. We also propose the method adjusting the disparity search range depending on edge information. The proposed technique reduces the calculation time efficiently while improving the matching accuracy.

• Korean Journal of Remote Sensing
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• v.33 no.5_1
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• pp.607-615
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• 2017

The aerosol optical thickness data retrieved by Moderate Resolution Imaging Spectrometer (MODIS) of Terra & Aqua and Meteorological Imager (MI) of Communication Ocean and Meteorological Satellite (COMS) are analyzed and compared with the measurement data of Aerosol Robotic Network (AERONET) in Northeast Asia. As the result, the aerosol optical thickness retrieved by MODIS and MI were well agreed at ocean region but quite different at cloud edge and barren surface. The reason was that MODIS aerosol optical thickness was retrieved using the visible and infrared channels but MI was retrieved with the visible channel only. Consequentially, the thin cloud be misinterpreted as aerosol by MI and the difference between MODIS and MI aerosol optical thicknesses could be occurred with Normal Distribution Vegetation Index (NDVI) and land surface property. Therefore, the accuracies of clear/cloud region and surface reflectivity are required in order to improve the aerosol optical thickness algorithm by MI.

• Journal of Korean Society of Steel Construction
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• v.27 no.4
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• pp.377-386
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• 2015

In this study, inelastic buckling strength of HSA800 steel columns were tested to investigate the applicability of current column curve (KBC2009, 2010 AISC-LRFD) to HSA800 steel. Key test variables included width-thickness ratio, plate-edge restraints, and column slenderness ratio. Specimens made of ordinary steel (SM490) were also tested for comparison purposes. All the concentrically loaded HSA800 specimens exhibited sufficient buckling strength compared to the current column curve, but some of SM490 specimens showed understrength. This difference can be explained by the lower residual stress present in HSA800 specimens.

• Journal of Soil and Groundwater Environment
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• v.22 no.3
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• pp.42-49
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• 2017

TOUGH2 was used to simulate the migration of $CO_2$ injected into a sandy aquifer. A series of numerical simulations was performed to investigate the effects of a low-permeability layer (LPL) embedded in the aquifer on the injection rate and the pressure distribution of $CO_2$. The results show that the size and location of the LPL greatly affected the spread of $CO_2$. The pressure difference between two points in the aquifer, one each below and above the LPL, increased as the size of the LPL increased, showing a critical value at 200 m, above which the size effect was diminished. The location of the LPL with respect to the injection well also affected the migration of $CO_2$. When the injection well was at the center of the LPL, the injection rate of $CO_2$ decreased by 5.0% compared to the case with no LPL. However, when the injection well was at the edge of the LPL, the injection rate was decreased by only 1.6%. The vertical distance between the injection point and the LPL also affected the injection rate. The closer the LPL was to the injection point, the lower the injection rate was, by up to 8.3%. Conclusively, in planning geologic storage of $CO_2$, the optimal location of the injection well should be determined considering the distribution of the LPL in the aquifer.

• Journal of Educational Research in Mathematics
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• v.15 no.2
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• pp.131-145
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• 2005

This study intends to analyze didactically on triangle-determining conditions and triangle-congruence conditions. The result of this study revealed the followings: Firstly, many pre-service mathematics teachers and secondary school students have insufficient understanding or misunderstanding on triangle-determining conditions and triangle-congruence conditions. Secondly, the term segment instead of edge may show well the concern of triangle-determining conditions. Thirdly, when students learn the method of finding six elements of triangle using the law of sines and cosines in high school, they should be given the opportunity to reflect the relation and the difference between triangle-determining situation and the situation of finding six elements of triangle. Fourthly, accepting some conditions like SSA-obtuse as a triangle-determining condition or not is not just a logical problem. It depends on the specific contexts investigating triangle-determining conditions. Fifthly, textbooks and classroom teaching need to guide students to discover triangle-deter-mining conditions in the process of inquiry from SSS, SSA, SAS, SAA, ASS, ASA, AAS, AAA to SSS, SAS, ASA, SAA. Sixthly, it is necessary to have students know the significance of 'correspondence' in congruence conditions. Finally, there are some problems of using the term 'correspondent' in describing triangle-congruence conditions.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.4
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• pp.405-412
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• 2012

After the spatial discrepancy between SLI(Street-Level Imagery) and vector map is removed by their conflation, the corresponding building regions can be found based on SLI parameters. The building region correspondence, however, is not perfect even after the conflation. This paper aims to improve the correspondence of building regions by region splitting of an SLI. Regions are initialized by the seed lines, projection of building objects onto SLI scene. First, sky images are generated by filtering, segmentation, and sky region detection. Candidates for split lines are detected by edge detector, and then images are splitted into building regions by optimal split lines based on color difference and sky existence. The experiments demonstrated that the proposed region splitting method had improved the accuracy of building region correspondence from 83.3% to 89.7%. The result can be utilized effectively for enhancement of SLI services.

• Journal of the Korean Society for Heat Treatment
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• v.9 no.4
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• pp.289-299
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• 1996

This study has been performed to investigate into some effects of power density and traverse speed of laser beam on the microstructure, hardness and residual stress of AISI 4140 treated by laser surface hardening technique. Optical micrograph has shown that large martensite and a small amount of retained austenite in outermost surface layer and fine lath martensite in inner surface hardened layer are formed under the condition of a given power density and traverse speed. Hardness measurements have revealed that as the power density increases at a given 2.0m/min of the traverse speed, the maximum hardness values of outermost surface hardened layer is increased from Hv=635 to Hv=670. X-ray analysis for residual stress has exhibited that low compressive residual stress values are obtained in center point of the cress section of surface hardened layer with in mid point between the edge and the center point, about 1.5mm from the center point, due simply to a difference in self-quenching rate. It has been shown that the higher the power density at a given traverse speed and the olwer the traverse speed at a given power density, the more the compressive residual stress values are increased due to an increase in the input heat of laser beam.

• The Journal of the Korea Contents Association
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• v.10 no.10
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• pp.1-8
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• 2010

Recently, the character image processing technology using portable device camera image at home and abroad are actively conducted, but Practical use are lower rate because of accuracy and time-consuming process problems. In this paper, we propose the license plate recognition method based on geometric information from portable device camera image. In the extracted license plate region we recognize characters using the chain code and the Thickness information through the cumulative projected edge after performing the pre-processing work considering the angle difference, the contrast enhancement and the low resolution from portable device camera image. The proposed algorithm is effective and accurate recognition by light and reducing the processing time. And, the results from the character recognition success rate was 95%. In the future, we will research about license plate recognition algorithm using long distance image or added motion blur image.