• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.5
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• pp.518-524
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• 2004

The feasibility of Y(z) curve method of scanning acoustic microscope using high frequency transducer was experimentally studied for assessment of the thermal degradation in Co-based superalloy. Thermal degradation was performed to simulate the microstructural changes in Co-based superalloy arising from long term exposure at high temperature. Longitudinal wave velocity measured by pulse echo method using 10MHz transducer and leaky surface acoustic wave (LSAW) velocity measured by V(z) curve method using 200MHE transducer were measured to investigate the effect on thermal degradation. Ultrasonic velocity decreased as the aging time increased in both ultrasonic waves. Moreover, the low frequency longitudinal wave velocity decreased a little. Otherwise, the high frequency LSAW velocity drastically decreased up to a maximum of 4.7% at the aging time of 4,000hours. A good correlation was found between LSAW and Vickers hardness. Consequently, V(z) curve method of SAM using high frequency transducer could be a potential tool for assessing thermal degradation.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.473-480
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• 2007

The dentigerous cyst originates through alteration of stellate reticulum after amelogenesis has completed, with accumulation of fluid between the layers of the reduced enamel epithelium or between this epithelium and the tooth crown. Its incidence is relatively high on 10s or 20s of age and it is always related to the unerupted crown. Generally, it has no symptom, however, if the cyst is large or accompanied with pus formation, swelling and pain may occur. In radiographic findings, it shows impacted crown surrounded by well defined unilocular radiolucent lesion and occasionally displacement of adjacent teeth or root resorption. The goal of treatment is complete elimination of abnormal tissue preserving the tooth involved in the cyst. Enucleation and marsupialization are commonly used for the treatment. Marsupialization is the procedure which removes the partial portion of the cystic wall and connects with the oral mucosa. As the pressure in the cyst decreases, bone regeneration takes place in the defect area and cystic wall converts into normal mucosa. This procedure, however, is the most conservative procedure which allows the protection of adjacent important structures. If the eruption space is sufficient, then inducing the eruption of the permanent tooth in the cyst is also possible. In following cases, dentigerous cyst was diaganosed after clinical and radiographic examination. Marsupialazation was done to remove the cyst and induce the tooth, which was in the cyst, to erupt into the oral cavity.

• Journal of Korean Orthopaedic Sports Medicine
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• v.9 no.2
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• pp.91-97
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• 2010

Purpose: The purpose of this study was to evaluate the results of treatment for longitudinal meniscal tear in ACL rupture patients by clinical evaluation and $2^{nd}$ look arthroscopy. Materials and Methods: Among the patients who underwent surgery due to ACL rupture and longitudinal meniscal tear between 2002~2009, 32 patients were selected for the study. The patients were devided into three groups; group 1 had repair, group 2 had partial menisectomy due to impossible to repair, group 3 had conservative treatment due to stable meniscus. Comparative retrospective analysis was applied with KT 1000 arthrometer, Lysolm' score, Tegner activity score, IKDC subjective score, and $2^{nd}$ look arthroscopy. Results: Lysolm' score, Tegner activity score, IKDC subjective score showed no statistical difference in all three groups. KT-1000 side to side difference improved from 6.2, 6.15, 6.38 before surgery to 2.56, 2.49, 2.58 after surgery in group 1, 2, and 3, respectively. In group 1, second-look arthroscopy revealed complete healing in 12 patients, incomplete healing without any clinical symptoms in 2, and healing failure in 1. In group 2, second-look arthroscopy showed partial regeneration on margin of meniscectomy. In group 3, second-look arthroscopy revealed complete healing in 2 patients, while 4 showed incomplete healing so that have repaired. Conclusion: In the study, the outcome was better when the stable longitudinal meniscal tear on posterior horn with ACL rupture had active treatment.

• Journal of Korea Multimedia Society
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• v.12 no.3
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• pp.335-344
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• 2009

Embedded systems and web browsers have started to provide two-dimensional vector graphics features, to finally support scalability of graphics outputs, while traditional graphics systems have focused on the raster and bitmap operations. Nowadays, SVG and Flash are actively used while OpenVG from Khronos group plays the role of a de facto low-level API standard to support them. In this paper, we represent the design and implementation process and the final results of an OpenVG implementation, AlexVG. From its design stage, our implementation aims at the cooperation with SVG-Tiny, another de facto standard for embedded systems. Currently, our overall system provides not only the OpenVG core features but also variety of OpenVG application programs and SVG-Tiny media file playing capabilities. For the conformance with the standard specifications, our system completely passed the whole OpenVG conformance test suites and the graphics output portions of the SVG-Tiny conformance test suites. From the performance point of view, we focused on the efficiency and effectiveness especially on the mobile phones and embedded devices with limited resources. As the result, it showed impressive benchmarks on the small-scale CPU's such as ARM's, even without neither any other libraries nor acceleration hardware.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.1
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• pp.166-173
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• 2014

A noncontact nondestructive testing (NDT) method is proposed to detect the damage of pipeline structures and to identify the location of the damage. To achieve this goal, a scanning laser source actuation technique is utilized to generate a guided wave and scans a specific area to find damage location more precisely. The ND: YAG pulsed laser is used to generate Lamb wave and a piezoelectric sensor is installed to measure the structural responses. The measured responses are analyzed using three dimensional Fourier transformation (3DFT). The damage-sensitive features are extracted by wavenumber filtering based on the 3D FT. Then, flaw imaging techniques of a pipeline structures is conducted using the damage-sensitive features. Finally, the pipes with notches are investigated to verify the effectiveness and the robustness of the proposed NDT approach.

• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.460-465
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• 2018

Deep sea water is deeper than 200 m in depth and maintains cool temperatures. It is clean seawater not contaminated by E. coli and other general bacteria. Because deep sea water is a recyclable resource with high industrial value, activities for commercial use are vigorously developing. We investigated safety, quality characteristics, and mineral contents of prototype products using deep sea water as a substitute for a curing agent and compared it with existing commercially processed products. This study examined the potential of deep sea water as an alternative to curing agent solution. As a result, safety and quality characteristics of processed meat products with deep sea water were not different from commercially processed meat products, but mineral contents were higher in processed meat products with deep sea water. Deep sea water could be widely used as purity salt and purity minerals that can replace chemical substances such as chemical salts. A new, active food market using deep sea water will emerge in the near future.

• Biomedical Science Letters
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• v.1 no.1
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• pp.81-88
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• 1995

RDW and MCV are thought to be the highly sensitive blood cell parameters in the differentiation of iron deficiency anemias. Through the medical records of 227 anemic patients and the physical checking results of 143 healthy persons in a General Hospital during the recent five years, the authors evaluated various blood cell parameters including RDW and MCV. Iron deficiency anemia, aplastic anemia and other anemias associated with chronic disease were shown as the three major causes of anemias in Korea. In the patients of iron deficiency anemia MCV was very low(62.9$\pm$13.7fl), while RDW was very high(19.3$\pm$4.8) showing much lower MCV and much higher RDW in severe IDA compared with in mild IDA. To differentiate iron deficiency anemias form other anemias, a discriminant function was developed from some blood cell parameters like MCV, MCH, MCHC, RDW and platelets(D.F.=0.26-0.012MCV -0.130MCH +0.073MCHC +0.052RDW+0.003PLT).

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.5
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• pp.132-140
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• 2016

In this paper, we propose boundary-preserving stereo matching method based on adaptive disparity adjustment using confidence region detection. To find the initial disparity map, we compute data cost using the color space (CIE Lab) combined with the gradient space and apply double cost aggregation. We perform left/right consistency checking to sort out the mismatched region. This consistency check typically fails for occluded and mismatched pixels. We mark a pixel in the left disparity map as "inconsistent", if the disparity value of its counterpart pixel differs by a value larger than one pixel. In order to distinguish errors caused by the disparity discontinuity, we first detect the confidence map using the Mean-shift segmentation in the initial disparity map. Using this confidence map, we then adjust the disparity map to reduce the errors in initial disparity map. Experimental results demonstrate that the proposed method produces higher quality disparity maps by successfully preserving disparity discontinuities compared to existing methods.

• Journal of Periodontal and Implant Science
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• v.35 no.1
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• pp.77-85
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• 2005

목적 : 이 연구의 목적은 치과 영역에서 골 재생을 촉진하기 위해, 현재 많이 사용하고 있는 BDX(bovinederived xenograft)와 비교하여 BCP(biphasic calcium phosphate)의 효과를 알아보기 위함이다. 실험 재료 및 방법: 본 연구는 태아골모세포주(hFOB 1.19)를 사용하였으며, 사용된 골 이식재에 따라 2개의 실험군으로 구분하였고, 각 실험에 적절한 농도의 BDX와 BCP를 첨가하였다. 그리고, 세포 증식도 검사, 교원질 합성량 분석, 염기성 인산분해효소 활성도 측정, Western blot 분석을 통한 OC과 BSP의 발현 정도등의 실험을 진행하였다. 결과 : BDX와 BCP는 대조군과 비교하여 세포 증식에서 유의한 차이가 없었지만, 교원질 합성량, 염기성 인산분해효소의 활성, 그리고 OC과 BSP의 발현에 있어 대조군과 비교하여 유의하게 증가를 보였다. 그러나, 두 이식재간의 유의한 차이는 보이지 않았다. 결론 : 본 실험실적 연구에서 BCP는 골모세포분화에 긍정적인 영향을 미침으로써 효과적인 이식재로 사용할 수 있음을 가늠할수 있었다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.130-136
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• 1997

Total parenteral nutritional effect was induced by surgical creation of Thiry-Vella fistula(TVFs) in rats. Glutamine, glycine or nucleosides/nucleotide mixture in solution was injected into the loops for 2, 4, 6, 8 days. Control animals received a 0.9％ saline solution. Results include weight gain, total protein, DNA, ［$^3$H］ thymidine incorporation into DNA, morphometry of the intestine in both TVFs and intestine in continuity. Perfusion of nucleosides/nucleotide mixture into the bypassed loops caused an increase in total protein, DNA content, villous height, villous surface area in loops. The injection of glycine into loops caused an increase in ［$^3$H］ thymidine incorporation but the mean values of the protein and DNA contents were not significantly different from those in group Cont and group Nuc. Overall values for group Gln were slightly higher than those of the control but the differences were not statistically significant. This study suggests that this animal model may be useful for studying the effect of dietary factors on intestinal growth and maturation, separating the direct effect of diet from systemic effect on the intestine.