• Journal of Biomedical Engineering Research
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• v.8 no.1
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• pp.81-86
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• 1987

An image feature extraction method for the low contrast fluoresceln angiogram in dlabetes was studied. To obtain effective image segmentation, an adaptive local difference image is generated and relaxation process are applied to this difference Image. By the use of distance transformed data with segmented image, shape and location of feature regions were obtained. It was shown that the location and shape descriptions of Impaired blood vessel networks and retinal regions are can he utilized for the diagnosis of diabetes and other disease.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.11a
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• pp.115-116
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• 2009

In this study, near-infrared absorbing dyes, namely, new rigidified heptamethine cyanine dyes were synthesized and investigated their properties. The cyanine dyes have been synthesized by a condensation reaction between a quanternary salt containing as activated methyl group and an unsaturated bisaldehyde or its equivalent. We were investigated the synthesis of new rigidified heptamethine cyanine and related the compounds with near infrared absorption. The full spectroscopic characterization of all cyanine were described. Absorption properties in the near-infrared region may cause these dyes to the potential used in bio-probe, optical recording media materials.

• 한국연소학회:학술대회논문집
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• 1998.10a
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• pp.91-101
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• 1998

The effect of secondary flow on both methane/air and propane/air premixed flame was investigated experimentally. By changing the radius of curvature, various flame behavior was observed. In the V-bend nozzles, flame surface is deformed from axisymmetry. As the exit velocity increased, flame lifted off partially. When the radius of curvature of the V-bend increased, the region where premixed flame is entirely on the rim increased. Since the axial velocity field is changed due to the secondary flow effect, comparison of V-bend and straight tube with the same diameter shows larger V-bend nozzle exit velocity for both flash back and flame blowout. The flame characteristics are mapped with a equivalence ratio, a velocity, and a nozzle radius of curvature. To identify physical reasoning on the flame surface deformation, numerical calculations are conducted. OH radical distributions in flames are visualized by PLIF technique.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.405-406
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• 2008

The amorphous indium zinc oxide (IZO) thin films were deposited on polyethersulfone (PES) and glass substrates by facing targets sputtering. IZO thin films deposited as functions of gas flow ratio on PES and glass substrates, respectively. The electrical, optical and structural properties of IZO thin films were evaluated by a Hall Effect Measurement, an X-Ray Diffractormeter, UV/VIS spectrometer in visible range and a scanning electron microscopy, respectively. As-deposited IZO thin films exhibited resistivity of $5.4\times10^{-4}$ and $4.5\times10^{-4}$ [$\Omega$-cm] on PES and glass substrates, respectively. The optical transmittance showed over 85% in the visible region on PES and glass substrates.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.6
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• pp.678-682
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• 2004

Generally Bi-2223/Ag tapes have a broad S/N transition region and their sheath is a good electric conductor. In this study, the current distribution between superconductor and metal sheath in HTS tapes were investigated. AC with its peak value above 10 times $I_{c}$ was applied to HTS tapes for around 6 cycles and V-I characteristics were measured. Using the resistance of the sheath and V-I curves, the current distribution between superconductor and metal sheath was calculated. When 150 $A_{p}$ was applied, more than 2/3 of the current flows through superconductor. However, in the case of 304 $A_{p}$, most of the applied current came to flow through the metal sheath at the 6th cycle.e.e.e.

• Journal of Veterinary Clinics
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• v.19 no.3
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• pp.371-374
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• 2002

A female 8-year-old Pug weighing 7.3 kg and a female 10-year-old Maltese dog weighing 3.5 kg showing anorexia and vomiting for a few weeks were referred to Veterinary Medical leaching Hospital, Seoul National University. Radiographic findings were an enlarged right kidney in a pug dog and a radiopaque material on the right ureteral region lateral to the third lumbar vertebrae with indefinite right kidney contour in a Maltese dog, repectively. Excretory urography performed in a Pug dog revealed a poor opacified enlarged right kidney with absent of pelvic recesses and pelvic dilation with proximal ureteral dilation on contralateral kidney. Ultrasonographic findings were enlarged kidney with dilated pelvis and echogenic sediment within the medulla in both dogs and especially an engorged proximal ureter and a thin rim of functional renal tissue remains in a Maltese dog. Those diagnostic findings indicated high possibility of pyelonephritis and these were confirmed by pathologic examination. Radiography and ultrasonography, although not giving final diagnosis for pyelonephritis, are useful for assessment and diagnosis of pyelonephritis.

• Journal of Auto-vehicle Safety Association
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• v.14 no.3
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• pp.30-34
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• 2022

The CFT(Cornering Fatigue test) and RFT(Radial Fatigue Test) are tests for evaluating the endurance of the disc and rim region of the wheel. In recent, automobile wheel safety standards have been revised and the applied load and target life criteria are different from existing conditions. The verification evaluation of all wheels requires a lot of time and cost. In this study, the endurance severity of each test was compared through strain-life approach by selecting 4 steel and 8 aluminum wheels.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.2
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• pp.130-136
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• 2005

Bone grafts are widely used in the reconstruction of osseous defects in the oral and maxillofacial region. Autogenous bone grafts are considered the gold standard in grafting of the oral and maxillofacial region, because of its osteoconductive and osteoinductive properties. Mandibular symphysis & ascending ramus bone graft have been used more frequently because of easy surgical access, reduced operative time, and following minimal morbidity. However, even though the frequent use of the anterior part of ascending ramus and the different regions of mandible, rare of the reports provide information about the quantity of bone available in this donor site. So this study was taken to evaluate & quantify the amount of bone graft material in the anterior ascending ramus regions. This study was made on 36 samples of CT image. In 3D volume image, imaginary osteotomy & segmentation were done and the dimensions and volume of the bone grafts were measured and evaluated. the average volume of the graft materials obtained from the ascending ramus was $3656.83{\pm}108.19mm^3$, and the average dimensions of graft materials were $(33.68{\pm}0.48){\times}(34.92{\pm}0.51){\times}(15.96{\pm}0.27){\times}(9.05{\pm}0.27)mm$.

• Journal of Broadcast Engineering
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• v.10 no.4 s.29
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• pp.632-642
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• 2005

This paper presents a new vertex selection scheme for the polygon-based contour approximation. In the proposed method, the entire contour is partitioned into partial segments and they are approximated adaptively with variable accuracy. The approximation accuracy of each segment is controlled based on its relative significance. By computing the relative significance with the texture degradation in the approximation error region, the visual quality enhancement in the reconstructed frames can be achieved under the same amount of the contour data. For this purpose, a decision rule for $d_{max}$ is derived based on inter-region contrasts. In addition, an adaptive vertex selection method using the derived rule is proposed. Experimental results are presented to show the superiority of the proposed method over conventional methods.

• Journal of Korea Multimedia Society
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• v.16 no.12
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• pp.1376-1384
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• 2013

In this paper, we propose an automaticdetection method of foreign bodies through template matching in industrial CT volume data. Our method is composed of three main steps. First,Indown-sampling data, the product region is separated from background after noise reduction and initial foreign-body candidates are extracted using mean and standard deviation of the product region. Then foreign-body candidates are extracted using K-means clustering. Second, the foreign body with different intensity of product region is detected using template matching. At this time, the template matching is performed by evaluating SSD orjoint entropy according to the size of detected foreign-body candidates. Third, to improve thedetection rate of foreign body in original volume data, final foreign bodiesare detected using percolation method. For the performance evaluation of our method, industrial CT volume data and simulation data are used. Then visual inspection and accuracy assessment are performed and processing time is measured. For accuracy assessment, density-based detection method is used as comparative method and Dice's coefficient is measured.