• 제어로봇시스템학회논문지
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• 제16권5호
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• pp.469-475
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• 2010

This paper presents a method of classifying discolored defects of metal pads using geometric texture for AFVI (Automated Final Vision Inspection) systems. In PCB manufacturing process, the metal pads on PCB can be oxidized and discolored partly due to various environmental factors. Nowadays the discolored defects are manually detected and rejected from the process. This paper proposes an efficient geometric texture feature, SUTF (Symmetry and Uniformity Texture Feature) based on the symmetric and uniform textural characteristics of the surface of circular metal pads for automating AFVI systems. In practical experiments with real samples acquired from a production line, 30 discolored images and 1232 roughness images are tested. The experimental results demonstrate that the proposed method using SUTFs provides better performance compared to Gabor feature with 0% FNR (False Negative Rate) and 1.46% FPR (False Positive Rate). The performance of the proposed method shows its applicability in the real manufacturing systems.

• 상하수도학회지
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• 제37권4호
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• pp.187-202
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• 2023

This study focuses on the application of a new measurement method that quantifies the residual color of filtered water using a spectrocolorimeter after filtering the discolored substances. It was confirmed through the color and turbidity cross-test that the discolored substances cannot be measured effectively with the current legal color and turbidity test method. Therefore, the National Institute of Environmental Research's filter testing method, which involves filtering the sample through 0.45 ㎛ filter and visually inspecting the color, was improved. A membrane filter colorimetry (MFC) method was established by measuring the color difference (ΔE*ab(65)) of the filtered filter using a spectrophotometer and expressing it as filter color unit (FCU). Using the MFC method, the FCU for reference materials such as iron and manganese, as well as field samples, was measured. The results showed a high correlation with turbidity, and the color difference patterns varied depending on the type of reference materials and field samples. This indicates that the MFC method is an effective new measurement method of discolored tap water.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2001년도 추계학술대회(제116회) 및 13회 Workshop 제3회 한ㆍ일 치과보존학회 공동학술대회 초록집
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• pp.591.1-591
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• 2001

This study was performed to evaluate internal bleaching effect of various bleaching agent on discolored nonvital teeth. 40 Human teeth were intentionally discolored with erythrocytes of human blood and randomly divided into 4 groups: 10% carbamide peroxide gel (Opalescence, Ultradent, U.S.A.); 15% carbamide peroxide gel; sodium perborate (Duksan pure chemical Co., Korea) with distilled water; sodium perborate with 30% hydrogen peroxide (Duksan pure chemical Co., Korea).(omitted)

• 대한소아치과학회지
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• 제21권2호
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• pp.593-598
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• 1994

There were two cases of esthetic improvement of discolored teeth. First case was 12-year-old girl whose upper right central incisor was discolored after traumatic injury. She was treated by walking bleaching technique. Endodontic retreatment was done, and then the mixture of Superoxol and sodium perborate was applied and changed every week. After 3 weeks, esthetic result was obtained and fracture site was rcovered with light-curing composite resin. Second cases was 11-year-old girl whose teeth were discolored by fluorosis. She was treated by vital bleaching technique. A resin splint was made and then 30% and 15% carbamide peroxide was applied using this splint. After 4 weeks, a noticeable improvement in the color and the brightness of the teeth was achieved.

• 대한장애인치과학회지
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• 제10권2호
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• pp.84-88
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• 2014

1. 순측접근법은 치수치료를 순측으로 시행한 후 변색된 순측의 치질을 확대하여 삭제하고 레진으로 순면전체를 수복함으로써 치수치료와 동시에 심미성을 회복할 수 있다. 2. 순측으로 치수치료를 시행하므로 시야가 확보에 유리하고 기구조작이 용이해 행동조절이 잘 되지 않는 어린이에게 추천된다.

• Journal of the Korean Wood Science and Technology
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• 제14권4호
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• pp.40-46
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• 1986

국내산(國內産) 16수종재의 철오염(鐵汚染), 알칼리오염(汚染) 산오염(酸汚染), 태양광(太陽光)에 의한 변색을 측정한 결과를 요약하면 다음과 같다. 1. 철오염(鐵汚染)이 심(甚)한 수종(樹種)은 일본잎갈나무, 신갈나무, 느티나무, 왕버섯나무등 이었고, 적은 수종(樹種)은 참오동나무, 리기다소나무등 이었다. 2. 국내산수종(國內産樹種)은 알칼리오염(汚染)이 적은 평이었고, 알칼리오염(汚染)이 낮은 수종은 젓나무, 음나무, 현사시, 고로쇠나무, 리기다소나무, 신갈나무, 자작나무, 왕벗나무, 느티나무, 이태리포플러, 잣나무, 참오동나무 등이었다. 3. 산오염(酸汚染)이 심(甚)한 수종(樹種)은 본(本) 실험(實驗)에서 사용재중(使用材中)에는 나타나지 않았고, 낮은 수종은 리기다소나무, 오동나무, 잣나무, 신갈나무, 음나무, 고로쇠나무 등 이었다. 4. 태양광(太陽光)에 의한 변색은 본(本) 실험(實驗)에서 사용(使用)한 공시재중(供試材中)에는 변색의 정도가 높은편으로서 변색이 심(甚)한 수종은 일본잎갈나무, 고로쇠나무, 참오도나무, 이태리포플러, 소나무, 아까시나무, 젓나무, 현사시, 느티나무, 왕벗나무, 리기다소나무 등이었으며, 태양광에 의한 변색이 낮은 수종(樹種)은 오리나무로서 국내산재 16수종이 태양광에 의한 변색의 정도가 높은 것이 특징이었다. 일반적(一般的)으로, 한국산(韓國産) 수종(樹種)은 태양광(太陽光)과 철오염(鐵汚染)에 의한 정도가 높은 편이었고, 알칼리오염(汚染)과 산오염(酸汚染)에 의한 변색은 낮은 편에 속하였다.

• 대한치과의사협회지
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• 제12권10호
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• pp.763-766
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• 1974

The electron microscopic observation on the browny discolored enamel spot on smooth surface of permanent teeth was performed by mean of the Filmy Replica method and obtained the following: 1) The browny discolored enamel spot on smooth surface of permanenet teeth was identified as a dental caries.

• 대한치과기공학회지
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• 제32권4호
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• pp.327-335
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• 2010

Purpose: The purpose of this study was to investigate the correlation between zirconia core thickness and color tone blocking of discolored tooth and metal post. Methods: For this study, we made 20-porcelain sample and 4-metal sample( liechtenstein IPS e.max) bonded to zirconia core of different thickness with cement(Relyx ARC-3M USA)for produce discolored. We measured the color-spectral characteristics, using Shadepilot equipment(Degudent USA).We measured it with Shadepilot equipment set by automated average mode in 3 times And applied the average value obtained from 2 times of measurement in the middle of each sample. Results: As a result of analysing color-spectral characteristics on zirconia core sample, Depending on the thickness of zirconia core, the value of brightness(${\Delta}L*$:color-spectral characteristic) was increased within limited range, value of ${\Delta}a*$, ${\Delta}b*$ was decrease. Conclusion: Consequently, we obtained the following results: Changes of sample color were observed depending on the thickness of zirconia, but the range of change did not exceed the scope range of shade guide. The case of metal posts, shade guide color D2 were observed in 0.5mm of zirconia core thickness. As a result, in case of porcelain, increasing the zirconia thickness of 0.3mm or more is unnecessary for color blocking effect, in case of metal post, considering the discolored tooth, thickness of zirconia with at least 0.5mm or more is recommended.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.187-187
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• 2022

Purple-discoloration of the uppermost leaves has been observed in some soybean cultivars in recent years. The purpose of this study was to characterize the novel phenotypic changes between the uppermost and middle leaves via multiple approaches. First, quantitative trait loci mapping was conducted to detect loci associated with the novel phenotype using 85 recombinant inbred lines (RILs) of the 'Daepung' × PI 96983 population. 180K SNP data, a major quantitative trait locus (QTL) was identified at around 60 cM of chromosome 6, which accounts for 56% of total phenotypic variance. The genomic interval is about ~700kb, and a list of annotated genes includes the T-gene which is known to control pubescence and seed coat color and is presumed to encode flavonoid 35-hydroxylase (F3'H). Based on Hyperspectral imaging, the reflectance at 528-554 nm wavelength band was extremely reduced in the uppermost leaves compared to the middle (green leaves), which is presumed die to the accumulation of anthocyanins. In addition, purple-discolored leaf tissues were observed and compared to normal leaves using a transmission electronic microscope (TEM). Base on observations of the cell organelles, the purple-discolored uppermost leaves had many pigments formed in the epidermal cells unlike the normal middle leaves, and the cell wall thickness was twice as thick in the discolored leaves. The thickness of the thylakoid layer in the chloroplast the number of starch grains, the size of starch all decreased in the discolored leaves, while the number of plastoglobule and mitochondria increased.

• 펄프종이기술
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• 제35권1호
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• pp.48-53
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• 2003

The objective of this study was to find in what color Korean handmade paper(Hanji) is dyed when it is dyed with a pigment extracted from waste onion peelings using different kinds of mordant, and how the paper is discolored and variety of strength under the condition of accelerated aging test. The results of this experiment are as follows. 1. Korean handmade paper was dyed in different colors according to the kinds of mordant. Mainly it was dyed in orange-brown, and sometimes in gold or khaki. 2. Korean handmade paper dyed was not discolored much, which suggests that the pigment is strong under the condition of aging. 3. As for durability, Korean handmade paper dyed in gold was strongest. Korean handmade paper, to which aluminum sulfate, iron sulfate or sodium dichromate was applied as mordant, had poor durability. Thus, these were not suitable as mordant.