• Korean Journal of Materials Research
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• v.20 no.10
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• pp.524-534
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• 2010

Glass was fabricated using refused coal ore obtained from the Dogye coal mine in Samcheok. We additionally used soda ash and calcium carbonate to make a glass with the chemical composition of soda-lime glass, and we also used white, brown, and green glass cullet to make various kinds of colored glass. Transparent glass was fabricated by melting batch materials including refused coal ore at $1550^{\circ}C$ for 1 hr in an electrical furnace. The light transmittance and color chromaticity were measured by a UV/VIS/NIR spectrometer. Transparent glass with a light transmittance of over 80% was fabricated using normal refused coal ore and white glass cullet. Various kinds of colored glass with a light transmittance of 30-80% were fabricated using refused coal ore and brown or green glass cullet. The light transmittance of the mixed color glass samples, fabricated using normal refused coal ore and brown glass cullet and green glass cullet, indicated 30-47%, a relatively low value, in the condition of a cullet ratio of 20-50%. The characteristics of the color chromaticity of the glass samples were indicated in a chromaticity diagram by x-coordinates, y-coordinates, Y (lightness). The values of x-coordinates and y-coordinates were moved with a regular directional property according to the kind and amount of glass cullet. Therefore, we concluded that refused coal ore can be used for raw materials of color glass products like art glass and glass tile.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1920-1922
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• 2003

We have fabricated the pyrex glass microlens using thermal reflow process. Fabricated microlens is the plano convex refractive type and was fabricated with pyrex glass-Si anodic bonding wafer. The etched circle or cylindrical pyrex glass pattern was melted in a furnace $800^{\circ}C$ to $900^{\circ}C$ for about 15min. The surface roughness of the microlenses was measured by the AFM and average surface roughness of the microlenses was below 15min. The radius of curvature of the microlens was measured with phase shift interferometer.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.19-20
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• 2019

This study investigated the possibility of strength development by incorporating the slighly coarser soda-lime glass powder (GP) with 0-100 wt.% of Ground Granulated Blast Furnace Slag (GGBS) to synthesis GGBS based geopolymer. Compressive strength, water absorption & apparent porosity, were experimentally determined. To determine the homogeneity of mix, the microstructure & elemental composition of samples were studied using SEM-EDS. Study reveals the improvement in strength and reduction in porosity for the samples containing up to 30% GP. Furthermore, the microstructure analyses confirmed the development of denser and compact structure with the incorporation of glass powder up to 30%.

• Journal of computational fluids engineering
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• v.15 no.4
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• pp.92-98
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• 2010

In a modern high speed drawing process of optical fibers, it is necessary to use helium as a cooling gas in a glass fiber cooling unit in order to sufficiently cool down the fast moving glass fiber freshly drawn from the heated silica preform in the furnace. Since the air is entrained unavoidably when the glass fiber passes through the cooling unit, the helium is needed to be injected constantly into the cooling unit. The present numerical study investigates and analyzes the air entrainment using an axisymmetric geometry of glass fiber cooling unit. The effects of helium injection rate and direction on the air entrainment rate are discussed in terms of helium purity of cooling gas inside the cooling unit. For a given rate of helium injection, it is found that there exists a certain drawing speed that results in sudden increase in the air entrainment rate, which leads to the decreasing helium purity and therefore the cooling performance of the glass fiber cooling unit. Also, the helium injection in aiding direction is found to be more advantageous than the injection in opposing direction.

• Korean Journal of Materials Research
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• v.16 no.12
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• pp.743-746
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• 2006

ZTA tubes were prepared by centrifugal casting and sintered at $1600^{\circ}C$ for 2 hrs. The ZTA tubes were machined into specimens of $3{\times}4{\times}40$ mm. Molten Soda lime glass (SLG) was penetrated into the surface of ZTA at an optimized condition of $1500^{\circ}C$ for the holding time of 5 h and furnace cooled. The extra glass on the surface was removed using a resin bonded diamond wheel. The glass penetrated samples were tested for their flexural strength using four point bend test. Vickers Indentation cracks were made on the glass penetrated surface at different loads of 9.8 N, 49 N, 98 N and 196 N. The residual compression on the surface enhanced the flexural strength and crack arrest behaviour remarkably. This was attributed to the thermoelastic mismatch between the glass and ZTA matrix during cooling.

• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.175-180
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• 2004

Improving furnace efficiency is a high priority need for aluminum, glass, steel and other metal casting industries. Oxy-fuel combustion is considered to be one of the most effective method to improve thermal efficiency and reduce $NO_x$, SOx and $CO_2$ emissions for high temperature furnaces. The characteristics of an oxy-fuel flame, in particular its shape, radiation profile and exhaust gas composition are considerably different to those of an air-fuel burner. For this reason, a new approach is needed regarding factors such as burner design, power input levels, number and positioning strategies of burners and also control philosophies. In this paper will discuss the latest developments of high performance oxy-fuel combustion reheating furnace system. This high performance oxy-fuel combustion system will be shown to be technologically superior to other types of combustion systems in the areas of fuel efficiency, emissions and productivity.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.3
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• pp.27-33
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• 2000

The selective chemical vapor deposition techniques for Cu metallization were studied. For enhancing the selectivity, furnace annealing and N$_{2}$ plasma were treated on patterned TiN/BPSG prior to the copper deposition. As a result, Cu did not deposited lead to suppressing the nucleation on BPSG singificantly. With the increasement the plasma treatment temperature, copper nucleation on BPSG was suppressed mote effectively, From TOF-SIMS(Time-of-Flight Secondary ion Mass Spectrometry), it is considered that annealing and N$_{2}$ plasma treatment remove hydroxyl(0-H) group so that eliminating the nucleation site for copper precursor enhance the selectivity.

• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.230-230
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• 2003

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.2920-2922
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• 1999

본 논문에서는 유리 용해로의 온도 제어 문제에 있어서, 퍼지 이론의 응용 방식을 제시한다. 유리용해로의 동특성을 분석하고, 이에 적합하도륵 기존 고전적인 제어기와 퍼지 로직을 결합하는 알고리듬을 제시한다. 제시된 제어기는 실제 용해로의 생산공정에 효율적으로 적용되었다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.6
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• pp.526-533
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• 2006

The prediction of heat-up time of an LCD glass plate in LCD glass pre-treatment process has been implemented in the present study. Firstly, the analytical solution for one-dimensional radiation heat transfer from IR heaters to a LCD glass plate is obtained. When the surface temperature of the IR heaters is set at 473 K, the heat-up time of LCD glass to averaged temperature of 383K is 28 seconds. In addition, a three dimensional full CFD analysis using STAR-CD is implemented in an effort to consider the effect of 3-D heat loss through the furnace walls. From the results of the 3-D CFB analysis, the heat-up time increases up to 32.5 seconds under the same conditions. When the IR heater temperature in creases up to 573 K, the heat-up time decreases to 12 seconds for the one-dimensional analytical solution and to 13.5 seconds for the 3-D CFD analysis, respectively.