• Journal of the Korean Vacuum Society
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• v.15 no.3
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• pp.266-272
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• 2006

Application of power higher than the optimum operation value to an external electrode fluorescent lamps(EEFL) leads to the formation of small holes, called pinholes, which subsequently leads to lamp failure. The pinholes come from the insulating breakdown of the capacitor which is the dielectric layer between an external electrode and glass tube. The power of insulation breakdown is proportional to the electric power applied to the lamp. When a lamp current is low in the glass tube of dielectric constant K, the dielectric field strength of pinholes is about 3K kV/mm. The field strength of insulation breakdown decreases as the lamp current increases.

• Restorative Dentistry and Endodontics
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• v.11 no.1
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• pp.33-41
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• 1985

The purpose of this study was to determine the extent of tooth structure crazing when pinhole were drilled in dentin at various distances from the dentionenamel junction, and when pins were inserted by hand wrench and Auto-klutch handpiece. Sixty freshly extracted teeth were embedded in blocks of cold-curing acrylic resin to a level 1mm apical to the cementoenamel junction, the crown of the teeth were removed to a level 1.5mm coronal to the cementoenamel junction. After being sectioned, the cut surface of the teeth were smoothed, and they were divided into 4 groups. Group I : 4 pinholes were drilled with self-threading Minim spiral drill and pins were inserted with hand wrench in fifteen teeth. Group II : 4 pinholes were drilled with self-threading Minim spiral drill and pins were inserted with Auto-klutch handpiece in fifteen teeth. Group III : 4 pinholes were drilled with self-threading Regular spiral drill and pins were inserted with hand wrench in fifteen teeth. Group IV : 4 pinholes were drilled with self-threading Regular spiral drill and pins were inserted with Auto-klutch handpiece in fifteen teeth. The cut surface were then examined microscopically for the presence or absence of craze line. The results were as follows: 1. The self-threading Minim pin groups (Group I & II) produced less craze lines than did the self-threading Regular pin groups (Group III & IV). 2. In the self-threading Minim pin groups, there was more craze lines with hand wrench (Group I) than with Auto-klutch handpiece (Group 11). 3. In the self-threading Regular pin groups, there was more craze lines with hand wrench (Group III) than with Auto-klutch handpiece (Group IV). 4. Placement of the pinhole at 0.0mm from the dentionenamel junction produced more craze lines than placed at 0.5mm, 1.0mm (p<0.05), however there was no statistically significant between the 0.5mm and 1.0mm distance.

• Journal of Korea Foundry Society
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• v.9 no.6
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• pp.446-453
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• 1989

무철심 유도로를 이용한 주철 및 주강의 용해보온에 요구되는 야금학적인 조건에 관하여 광범한 연구 조사가 있었다. 가장 중요한 법칙을 요약 설명하고자 한다. 이들 법칙은 주물공장에서 활용할 수 있으며 주물의 모서리 근처, 가혹한 조건하에서 발생 할 수 있는 여러 가지 결함을 방지하는데 도움이 될 것이다. 이러한 점에서 작업공정 절차를 관찰하는 것이 중요하며 현장에서 사용하도록 판정도표를 작성하였다.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.3
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• pp.273-278
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• 2014

On poly and single crystalline Cu substrates, the graphene was synthesized by chemical vapor deposition(CVD). Optical microscopic images which were not possible to show the detailed characterization of graphene growth were adjusted and analyzed using image analyzing software. As a result it was possible to show the detailed growth mechanism of graphene by utilizing the image analysis. Nucleation of graphene on Cu grain boundary and its growth behavior into Cu grain are shown. In addition, the movement of graphene grain boundary interacting with Cu grain boundary and pinholes during growth was illustrated in detail, and the cause and result are discussed as a result of those interactions.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.84.1-84.1
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• 2011

Typical solid oxide fuel cells (SOFCs) have limited applications because they operate at high temperature due to low ionic conductivity of electrolyte. Thin film solid oxide fuel cell with yttria stabilized zirconia (YSZ) electrolyte is developed to decrease operating temperature. Pt/YSZ/Pt thin film SOFC was fabricated on anodic aluminum oxide (AAO). The crystalline structure of YSZ electrolyte by sputter is heavily depends on the roughness of porous Pt layer, which results in pinholes. To deposit YSZ electrolyte without pinholes and electrical shortage, it is necessary to deposit smoother and denser layer between Pt anode layer and YSZ layer by sputter. Atomic Layer Deposition (ALD) technique is used to deposit pre-YSZ layer, and it improved electrolyte quality. 300nm thick Bi-layered YSZ electrolyte was successfully deposited without electrical shortage.

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.39-40
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• 2006

Digital image-projection and several modifications are the classical applications of Digital Micromirror Devices (DMD), however further applications in the field of optical metrology are also available. Operated with certain patterns, a DMD can function, for instance, as an array of pinholes that may substitute the Galvanic mirror or the stage scanning system presently used for 2 dimensional scanning in confocal microscopes. The various process parameters that influence the result of measurement (e.g. pinhole size, lateral scanning pitch and the number of pinholes used simultaneously, etc.) should be configured precisely for individual measurements by appropriately operating the DMD. This paper presents suitable conditions for the diffraction limited analysis between DMD-optics-CCD to achieve the best performance. Also sampling theorem that is necessary for the image acquisition by scanning system is simulated with OPTISCAN which is the simulator based on the diffraction theory.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.1
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• pp.99-102
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• 2002

Pinholes on the thermally grown oxide, which is called gate oxide, on silicon substrate under polysilicon layer are found and its mechanism is analyzed in this paper. The oxide under a polysilicon layer is broken during the plasma etching process of other polysilicon layer. Both polysilicon layers are separated with 0.8${\mu}{\textrm}{m}$ thick oxide deposited by CVD (Chemical Vapor Deposition). Since broken oxide points are found scattered around an arc occurrence point, it is assumed that an extremely high electric field generated near the arc occurrence point makes the gate oxide broken. 1'he arc occurrence point has been observed on the alignment key and is the mark of low yield. It is found that any arc occurrence can cause chips to fail by breaking the gate oxide, even if are occurrence points are found on scribeline.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.05a
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• pp.99-104
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• 2003

TiN coated films show a good mechanical properties, high thermal properties and wear, erosion and corrosion resistance and are widely used as a coating materials in tools, ornaments, parts and semiconductors. In spite of these good properties, the fracture of TiN coated films occur during use. The fracture of TiN thin films is related to their microstructure. Especially, the life of TiN coated layer is related to the texture of the TiN films. One researcher suggested that the corrosion and erosion resistance of the TiN thin films is related to a uniform and dense structure of films. In this study, we studied the relationships between textures and friction coefficient, erosion and corrosion in TiN coated films. The flatness of (115) texture surface of TiN thin films is flatter than that of (111) texture surface. The friction coefficient of (115) texture surface of TiN thin films is similar with that of (111) texture surface. The wear resistance of (115) texture surface of TiN thin films is better than that of (111) texture surface. The erosion and corrosion resistance of (115) texture surface of TiN thin films is better than that of (111) torture surface. As well as texture, the wear, erosion and corrosion of TiN thin films has to consider defects such as pinholes, cracks, surface roughness and open columnar structure. The life of TiN coated products is influenced by the properties of wear, erosion, and corrosion resistance of TiN thin films and is related to texture of TiN coated films, density of pinholes and cracks, density of structure, and surface flatness.

• Animal Systematics, Evolution and Diversity
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• v.13 no.3
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• pp.221-231
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• 1997

Marine harpacticoid copepods of the genus parathalestris, which are suspected as a chief cause of pinholes or galls of cultivated seaweeds like Undaria pinnatifida, are studied taxonomically. As a result of examining the specimens from 23 localities in Korea since 1989, the authors confirmed sic species of the genus Parathalestris including a new species, P. parviseta n. sp., and four species new to korean fauna: P. bulbiseta Lang, 1965; P. verrucosa Ito, 1970; P. pacificus Tschislenko, 1971 and P. arelata Ito, 1972. A key to these six species of parathalestris was made out, with the illustrations for them.

• Journal of Internet Computing and Services
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• v.13 no.3
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• pp.17-22
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• 2012

In this paper, a photoelectric image detection system is proposed using an APD(Avalanche Photodiode) sensor, a LED illuminator, and fiberoptic waveguides. This proposed pinhole detection system can detect the pinholes of 100 micron with the speed rate of 1,000mpm(meter per minute). And detecting performance of image system is improved by the SQL based DB analysis of classifying pinhole's detected location and size using image detection algorithms.