• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.11
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• pp.84-90
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• 1992

The dependence of electrical characteristics of RuO$_2$-based thick film resistors on the RuO$_2$ contents, glass composition variation and the firing temperatures was measured. The sheet resistance of resistors decreased as the contents of RuO$_2$ increased and at firing temperatures higher than C, the sheet resistance increased as the firing temperature increased. In case of using lead borosilicate glass-containing $Bi_{2}O_{3}$, the sheet resistance decreased as the contents of $Bi_{2}O_{3}$ increased. TCR changes from negative to positive values as RuO$_2$ contents increased and from positive to negative values as the firing temperature increased. TCR increased to positive values as $Bi_{2}O_{3}$ increased in the glass.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.205-210
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• 2000

Lead titanate thin films were fabricated on Si(100) wafer and ITO-coated glass substrates by metal organic chemical vapor deposition using ultrasonic spraying. When the ratio (Ti/Pb) of starting materials was 1.2, the films deposited on Si wafer had a single perovskite phase. The films deposited on ITO-coated glass had higher growth rate than that on Si wafer. As deposition temperature was increased from $530^{\circ}C$ to $570^{\circ}C$, dielectric constant was increased due to the increase of crystallinity and grain size. At $570^{\circ}C$, dielectric constant and dielectric loss of the films were 205 and 0.016, respectively. When the deposition temperature is higher than $600^{\circ}C$, dielectric constant was decreased.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.5
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• pp.434-439
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• 2008

Silver pastes as the outer electrodes have been prepared using Pb-free glass frits with different content of $Bi_2O_3$ and the effects of glass composition on the degradation behaviors of the Ag electrodes were investigated using the change of adhesion between Ag electrode and alumina substrate with thermal cycle stress. Low adhesion and high surface resistance were observed in Ag electrode using glass frit with a $Bi_2O_3$ content of 60 wt%, owing to the open microstructure formed at the firing temperature of $600^{\circ}C$. When the $Bi_2O_3$ was increased to 80 wt% in the glass frit, the Ag electrodes had a dense microstructure with high adhesion and a low surface resistance. Delamination of the Ag electrodes was a major failure mode under thermal cycle stress and this was attributed to residual stress due to the thermal expansion mismatch between the Ag electrode and the alumina substrate.

• Progress in Medical Physics
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• v.22 no.1
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• pp.3-11
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• 2011

The purpose of this study was to evaluate feasibility of Vertical Multileaf Collimator for determination of irradiation size using Vertical Multileaf Collimator and lead block to determine 4 different irradiation shape in case of Co-60 gamma-ray and 6 MV X-ray. We chose ion chamber, glass dosimeter and EBT chromic film to compare with Vertical Multileaf Collimator results and lead block results. In case of Co-60 gamma-ray and 6 MV X-ray, the central axis point dose normalized at reference field of lead block with ion chamber results for Vertical Multileaf Collimator were estimated higher than lead block about 5.1%, 4.2%. In case of Co-60 gamma-ray, the central axis point dose normalized at reference field of lead block with glass dosimeter results for Vertical Multileaf Collimator were estimated higher than lead block about 2.2%, 7.8%, 7.2%, 4.0% for reference, circle, triangle, cross field, respectively. In case of 6 MV X-ray, the central axis point dose normalized at reference field of lead block with glass dosimeter results for Vertical Multileaf Collimator were estimated higher than lead block about 6.7%, 6.2%, 3.8%, 6.2% for reference, circle, triangle, cross field, respectively. The results of EBT chromic film, Vertical Multileaf Collimator of penumbra size for all irradiation shape was smaller than lead block of those size that 2.0~3.5 mm for Co-60 gamma-ray, 0.5~1.0 mm for 6 MV X-ray. The results from this study, radiation treatment volume that results in shielding block can be minimized. In addition, during radiation treatment for 2, 3-dimensional radiation therapy using a Vertical Multileaf Collimator of this survey can be used to determine variety of irradiation fields.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.31-36
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• 2018

Fuses are used to protect electric circuits or devices from excess current. Glass-tube fuses are typically used, but problems have arisen due to the mandated switch from conventional solder to lead-free solder. This study used CFD to simulate the phenomenon of molten solder being poured out of a fuse during the soldering process for a fuse cap and fuse element. In addition, a method is proposed to prevent solder from overflowing, and its effectiveness was verified based on the analysis results. The results show that a sufficient increase of the temperature inside the glass tube before soldering and gravity can help to prevent the solder from overflowing.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.1
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• pp.1-7
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• 1990

Theoretical evaluations of the vertical displacement at the epicenter on the circular glass plate have been carried out in the case of the unit point loading(1 dyne force strength) with the Heaviside step-function time dependency. Acoustic emission signals generated during pencil lead($\Phi$=0.5mm, HB) fracture on the soda-lime glass($\Phi$=22cm, thickness=2.8cm) were observed by the optical Michelson interferometer with the stabilized circuit, and then the source function of the observed acoustic emission signals was analyzed by the deconvolution method. The source function of acoustic emission during pencil lead fracture had a 'dip' of~0.7$\mu$sec duration time at the front portion and a step function of~0.5$\mu$sec rise time with a force strength of~4.5N.

• Journal of Acupuncture Research
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• v.38 no.1
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• pp.41-46
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• 2021

Background: Pressure changes related to temperature variation during cupping may lead to dropout. This study aimed to investigate pressure changes related to temperature variations in the cup during the cupping procedure. Methods: Changes in temperature and pressure were measured for 15 minutes after the procedure was performed using the alcohol rub method with glass cups and with the addition of infrared irradiation. Changes in temperature and pressure were also measured for 15 minutes after pumping 3 times using the valve suction method, and with the addition of infrared irradiation. Results: In a comparison between the alcohol rub method with glass cups and with the addition of infrared irradiation, the negative pressure increased over time in the absence of infrared irradiation, whereas it decreased when performed with infrared irradiation p = 0.094. However, in a comparison between pumping 3 times using the valve suction method, and with the addition of infrared irradiation, the negative pressure decreased in both cases, but this was more significant with infrared irradiation p = 0.172. There was a significantly higher temperature in the glass cups (p = 0.004) and the valve cups (p = 0.001) exposed to infrared radiation, compared with no infrared irradiation. Conclusion: The reduction in negative pressure inside the cups exposed to infrared radiation was greater than without infrared irradiation. Temperature increases inside the cup can lead to the risk of dropout.

• Journal of Conservation Science
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• v.34 no.2
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• pp.119-128
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• 2018

This study revealed the material composition and characteristics of 19 glass fragments excavated from stone chamber No. 1 of Jeongchon Tomb in Naju through chemical composition analyses and observations. These characteristics were compared with the characteristics of the glass fragments excavated from No. 3 tomb of Bogam-ri in Naju. The purpose of this study was to identify the characteristics of the ancient glass of the Mahan-Baekje period. The glass fragments excavated from the Jeongchon Tombs can be classified into purplish blue, light-purplish blue, greenish blue, green, and mixture of purple blue and purple, based on their color. These beads were made using a drawn and casting technique. In addition, blue glass fragments were primarily excavated form No. 3 tomb of Bogam-ri. However, red glass fragments were not excavated from either of the tombs. According to chemical composition analyses, soda glass group and potash glass group were common in both the tombs. Additionally, alkali mixed glass group and lead barium glass group were excavated from Jeongchon Tombs and No. 3 tomb of Bogam-ri, respectively. The glass fragments excavated from No. 3 tomb of Bogam-ri have more color variations than those excavated from Jeongchon Tombs.

• Economic and Environmental Geology
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• v.46 no.6
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• pp.477-484
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• 2013

In order to recover gold from iron-hydroxide in acid mine drainage, a lead-fire assay has been used. Acid mine drainage is generated from mining waste rocks, and iron-hydroxide precipitates from acid mine drainage, which severely contaminates the area surrounding the mine. Iron-hydroxide samples contain on average 520.29 mg/kg of Fe, 4,414.62 mg/kg sulfur, and 16.19 mg/kg Au. In an XRD analysis, quartz and goethite were observed along with the iron-hydroxide. Using a lead-fire assay, the recovery of pure gold was on average 0.174 g/ton from the iron-hydroxide, whereas the gold not recovered in the process was on average 1.37 mg/kg. This unrecovered gold was lost to the glass slag due to the galena and lead formation. The galena and lead in the glass slag was identified through XRD.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.329-329
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• 2007

Photoconductive poly crystalline lead oxide coated on amorphous thin film transistor (TFT) arrays is the best candidate for direct digital x-ray detector for medical imaging. Thicker films with lessening density often show lower x-ray induced charge generation and collection becomes less efficient. In this work, we present a new methodology used for the high density deposition of PbO. We investigate the structural properties of the films using X-ray diffraction and electron microscopy experiments. The film coatings of approximately $200\;{\mu}m$ thickness were deposited on $2"{\times}2"$ conductive-coated glass substrates for measurements of dark current and x-ray sensitivity. The lead oxide (PbO) films of $200\;{\mu}m$ thickness were deposited on glass substrates using a wet coating process in room temperature. The influence of post-deposition annealing on the characteristics of the lead oxide films was investigated in detail. X-ray diffraction and scanning electron microscopy, and atomic force microscopy have been employed to obtain information on the morphology and crystallization of the films. Also we measured dark current, x-ray sensitivity and linearity for investigation of the electrical characteristics of films. It was found that the annealing conditions strongly affect the electrical properties of the films. The x-ray induced output charges of films annealed in oxygen gas increases dramatically with increasing annealing temperatures up to $500^{\circ}C$ but then drops for higher temperature anneals. Consequently, the more we increase the annealing temperatures, the better density and film quality of the lead oxide. Analysis of this data suggests that incorporation and decomposition reactions of oxygen can be controlled to change the detection properties of the lead oxide film significantly. Post-deposition thermal annealing is also used for densely film. The PbO films that are grown by new methodology exhibit good morphology of high density structure and provide less than $10\;pA/mm^2$ dark currents as they show saturation in gain (at approximate fields of $4\;V/{\mu}m$). The ability to operate at low voltage gives adequate dark currents for most applications and allows voltage electronics designs.