• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.169-170
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.791-792
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• 2010

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.7
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• pp.1280-1287
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• 2002

The old technique of sandblasting which has been used for decoration of glass surface has recently been developed into a powder blasting technique for brittle materials such as glass, silicon and ceramics, capable of producing micro structures larger than $100{\mu}$ m. This paper describes the performance of powder blasting technique in micro-line grooving of glass and the effect of the number of nozzle scanning on the depth and width of line groove. Experimental results showed that increasing the no. of nozzle scanning resulted in the increase of depth and width in grooves. Increase of width which may cause several problems in the precision machining results from wear of mask film. Therefore, well-controlled masking process is the most important factor for micro machining of glass with accuracy.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.294-299
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• 2001

The old technique of sandblasting which has been used for decoration of glass surface has recently been developed into a powder blasting technique for various materials, capable of producing micro structures larger than 100 m. This paper describes the performance of powder blasting technique in micro-line grooving of glass and the effect of the number of nozzle scanning on the depth and width of line groove. Experimental results showed that increasing the no. of nozzle scanning resulted in the increase of depth and width in grooves. Increase of width which may cause several problems in the precision machining results from wear of mask film.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1137-1138
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• 2011

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.4
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• pp.564-573
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• 2001

The mechanical properties of short carbon/glass fiber reinforced polypropylene are experimentally measured as functions of fiber content and nozzle diameter. Also, these properties are compared with the survival rate of reinforced fibers and fiber volume fraction using image analysis after pyrolytic decomposition. The survival rate of fiber aspect ratio as well as fiber volume fraction is influenced by injection processing condition, the used materials and mold conditions such as diameter of nozzle, etc. In this study, the survival rate of fiber aspect ratio is investigated by nozzle size variations in injection/mold sides. It is found that the survival rate of glass fiber is higher that the survival rate of glass fiber is higher than that of carbon fiber. Both tensile modulus and strength of short-fiber reinforced polypropylene are improved s the fiber volume fraction and nozzle diameter are increased.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.3
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• pp.183-190
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• 1994

Performance of domestic glass fabrics was tested in a Pulse- jet cleaned fabric filter under simulated coal combustion. Pulse Pressure were 2.5, 4.0kgf/$\textrm{cm}^2$ and pulse air nozzle diameter were 4.0, 6.0mm Pressure drop and penetration turned out to be low at small pulse air nozzle diameter and low pulse air pressure. Fractional penetration through the dust cake and fabric at face velocity of 1.7m/min was higher than that at face velocity of 1.0m/min. As a consequense, the performance of domestic glass fabrics was better with face velocity of less than 1.0m/min, pulse air pressure of 2.5 kgf/$\textrm{cm}^2$ and pusle air nozzle diameter of 4.0mm.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.3
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• pp.267-273
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• 2001

In this study, the survival rate of fiber is investigated by nozzle size difference in injection/mold sides. The survival rate of fiber is influenced about the nozzle size differ. Also, The mechanical properties of short carbon glass fiber reinforced polypropylene are experimentally measured as functions of fiber volume fraction and nozzle size difference. These mechanical properties are compared with the survival rate of fiber and fiber volume fraction using image analysis after pyrolytic decomposition. The survival rate of fiber as well as fiber volume fraction is influenced by injection processing condition, the used materials, mold conditions and nozzle sides difference, etc, In particular, the survival rate of fiber is great influenced when injection/mold nozzle sides are different more than that of the same. Consequently, the mechanical properties of short carbon/glass fiber reinforced polypropylene arc improved as the nozzle sides are the same in injection mold sides.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.8 no.4
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• pp.14-19
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• 2009

Micro fluid channels are machined on quartz glass using powder blasting, and the machining characteristics of the channels are experimentally evaluated. The powder blasting process parameters such as injection pressure, abrasive particle size and density, stand-off distance, number of nozzle scanning, and shape/size of the required patterns affect machining results. In this study, the influence of the number of nozzle scanning, abrasive particle size, and blasting pressure on the formation of micro channels is investigated. Machined shapes and surface roughness are measured, and the results are discussed. Through the experiments and analysis, LOC are ettectinely machined on quartz glass using powder blasting.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.5
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• pp.1-8
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• 2007

The present research is based upon the numerical analysis of a car windshield in order to represent the optimum design guide to improve the overall defrosting performance of the system. First, the control factors that highly affect the defrosting performance of a car windshield are chosen and afterwards, the optimum variables of each control factor are extracted out to analyze its performance. The main control factors for this research are respectively, the air injection angle of a defroster nozzle, the height of a nozzle outlet, and the ratio of the width to the height of a nozzle outlet. For such case when the air inlet angle is relatively small, the flow near the vicinity of the inner face of a windshield tends to expand. As a consequence, the heat transfer rate through the windshield decreases. Also, the height of a nozzle outlet is recommended to maintain its size to minimum. However, when the ratio mentioned before is designed less than unity, the defrosting performance decreases.