• Title/Summary/Keyword: Doming

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A Study on AK Shadow Mask with Fe-Ni Alloy Coating for Flat CPTs

  • Kim, Sang-Mun
    • Journal of Information Display
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    • v.5 no.4
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    • pp.27-30
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    • 2004
  • This paper investigates the effects of coating such as Invar (Fe-36% Ni), Fe-Ni Alloys and $WO_3$ on the doming property of aluminum killed (AK) shadow masks, which may be used for flat CPTs. Invar and Fe-Ni Alloys are deposited on AK shadow mask in plasma atmosphere and annealed. $WO_3$ is screen-printed on the deposited layer. The coating is observed to cause a decrease in the doming property of the shadow masks due to their lower thermal expansion coefficients and anti-doming properties.

The Effects of the Electron Reflecting Layer Screen-printed with the Lead Tungsten Oxides on the Shadow Mask in CRT

  • Kim, Sang-Mun
    • Journal of the Korean Ceramic Society
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    • v.40 no.2
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    • pp.113-117
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    • 2003
  • To reduce the doming of the shadow mask due to thermal expansion and to prevent the color discrepancy, the electron reflecting layer with lead tungsten oxides on the electron gun side of shadow mask was formed by screen printing method and doming property was evaluated in CRT. First, the lead tungsten oxides were prepared by calcining the mixture of lead oxide and tungsten oxide above 600$^{\circ}C$. Second, the paste which has the anti-doming composition including the lead tungsten oxides was coated by screen-printing method. As a result, the doming of the shadow mask was reduced about from 30 to 45%.

FE Analysis on Doming & Necking Process of Steel D&I Can (Steel D&I Can의 Doming 및 Necking 공정의 FEM 해석)

  • Jung, S.W.;Nam, J.B.;You, C.S.;Jin, Y.S.;Han, K.S.
    • Proceedings of the KSME Conference
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    • 2000.11a
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    • pp.452-457
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    • 2000
  • The object of this study is to develop a reliable FEM simulation technique for the analysis of can making process using PAM-STAMP software. The processes consist of doming and necking in addition to drawing, redrawing. After body making process, this study analyzed the stability for internal pressure by simulating buckling test. Through these technique, we estimated the dome reversal pressure of steel D&I Can for various can profile and process conditions. From this study, we found the cause and mechanism of wrinkling during necking process. This mechanism is largely affected by can wall thickness and the clearance between knock out punch and necking die. The dome reversal pressure improves with increasing dome depth. These results validate the usefulness of the developed simulation technique for the analysis of body making process and optimization of the dome profile.

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Numerical Study of the Butting Process for a AZ31B Magnesium Alloy Tube (마그네슘 합금(AZ31B) 버티드 튜브 성형 공정 해석)

  • Han, S.S.;Lee, M.Y.
    • Transactions of Materials Processing
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    • v.22 no.8
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    • pp.486-491
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    • 2013
  • A numerical investigation of the butting process for an AZ31B magnesium alloy tube at elevated temperatures was conducted to develop a double-butted magnesium alloy tube. As a result of the current study, it was found that the amount of doming of the tube end, prior ironing-extrusion to obtain high wall thickness reduction are important factors for the butting process of magnesium alloy tubes. There is also a limitation of the thickness profile of butted tube due to buckling of tube wall during the stripping stage.

Effects of the Nanometer-sized Bismuth Oxide Coating on Shadow Mask

  • Kim, Sang-Mun;Koh, Nam-Je
    • Journal of Information Display
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    • v.6 no.4
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    • pp.40-44
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    • 2005
  • Nanometer-sized bismuth oxide with a diameter of about 80 nm was used as a new electron reflection material in a 29" Real Flat CPT. This bismuth oxide was well dispersed over pH8 in slurry. Spray coating was performed clearly and uniformly and was ensured that there was no clogging of shadow mask hole. Coating thickness was expressed to the brightness of chromaticity for the sprayed layer and was also well controlled during the spraying process. Doming was improved by about 10% in spite of the similar coating weight in comparison with the average 3.5 ${\mu}m$ of the conventional bismuth oxide.

Electron Reflecting Layer with the WO3-ZnS:Cu.Al-PbO-SiO2 System Concerned in Doming Property of Shadow Mask in CRT

  • Kim, Sang-Mun;Cho, Yoon-Lae
    • Journal of the Korean Ceramic Society
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    • v.39 no.12
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    • pp.1124-1127
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    • 2002
  • In this paper, we studied the effects of the electron reflection on shadow mask on which the electron reflecting materials with $WO_3-ZnS:Cu.Al-PbO-SiO_2$ system were screen-printed and we evaluated the variation of the electron beam mislanding in CRT. As a result, the green emitted spectra on the electron reflecting layer are observed due to the transformation of the electron energy, when the electron impacted on shadow mask. The beam mislanding is reduced about 40% in comperision with that of CRT made by the conventional method.

Finite Element Analysis for the Body-making Process of Steel D&I Can (Steel D&I Can 몸체성형을 위한 FEM 해석)

  • Jung, S.W.;Jung, C.K.;Nam, J.B.;Jin, Y.S.;Han, K.S.
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.459-464
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    • 2001
  • The main object of this study is to develop a reliable FEM simulation technique for the analysis of Steel D&I Can bodymaking process using ABAQUS software. The body making process includes drawing, redrawing, 3 step ironing, doming. The newly developed FEM code in this research is based on the previous research achievement of POSCO for the drawing, redrawing and ironing process. The analysis is performed using two dimensional axisymmetric elements to analyze the punch force, the height of can, the distribution of residual stress and strain. The effect of blank thickness, gap of ironing die is also analyzed.

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A Study on the Application of Quality Certification System in Library Services (도서관 서비스의 품질인증제도 활용에 관한 연구)

  • Lee, Sang-Bok
    • Journal of the Korean Society for Library and Information Science
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    • v.36 no.1
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    • pp.211-231
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    • 2002
  • The purpose of this study is to apply the international quality certification system to service quality evaluation in library and information service centers. The study compared various aspects of their quality certification systems and considered application studies of foreign libraries. The results of this study illustrate that TQM based quality certification systems-Doming Quality Prize, Malcolm Baldrige National Quality Awards. European Quality Awards-reflects a broader, more dynamic and custome-oriented quality concepts. On the contrary, ISO 9000 Standards are based on a narrow, static and in house-oriented quality concepts emphasizing conformance to specifications.

The medical management of mitral stenosis in a Bull Terrier

  • Kun Ho Song;Aleksandra Domanjko Petric
    • Korean Journal of Veterinary Service
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    • v.46 no.1
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    • pp.75-79
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    • 2023
  • An eight-year-old, 28-kg male bull terrier who showed signs of lethargy and cough was referred for further evaluation of congestive heart failure. On presentation, physical examination revealed a systolic murmur at the left apex of the heart. Moreover, chest radiograph evaluation confirmed the mild alveolar and interstitial patterns in the caudal lung lobes and a grossly enlarged left atrium and left ventricle. Electrocardiography showed atrial fibrillation with a wide QRS complex, and transthoracic echocardiography revealed marked enlargement of the left atrium with abnormal morphology of the mitral valve. The thickened, hammer-like appearance and abnormal diastolic motion of the mitral valve leaflets were characterized by decreased leaflet separation and doming of the valve. The diagnosis was mitral stenosis with congestive heart failure and atrial fibrillation. The owner declined interventional valvuloplasty. Medical treatment included furosemide, pimobendan and diltiazem. Regular health check-ups have shown that vitality and clinical signs have improved considerably, and the dog have remained stable for 6 months after the presentation.