• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.26-31
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• 2001

Recently, miniaturization and mass production are the main trends in manufacturing fields. Therefore, ultraprecision machining and MEMS technology have been taken more and more important position in machining of microparts. Micro endmilling is one of the prominent technology that has wide spectrum of application field ranging from macro parts to micro products, such as PDP and IT components, in precision products manufacturing. However, the deburring is significant problem in making smooth and precise parts in micro endmilling. This paper shows removal characteristics of burr generated by micro endmilling process. Additionally, it is necessary to understand the formation mechanism of burr of micro barrier ribs to find proper deburring method.

• The Korean Journal of Nuclear Medicine
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• v.26 no.1
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• pp.155-159
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• 1992

Sternocostoclavicular hyperostosis (SCCH) is a chronic, nonsuppurative inflammatory disease involving sternum, clavicle, upper ribs and its adjacent soft tissue. It is a relatively newly described syndrome, characterized by ossification in the region between the clavicle and the first rib, and hyperostosis of the medial end of the clavicle with simultaneous involvement of the sternum and juxtasternal ribs. We experienced one case of sternocostoclavicular hyperostosis, diagnosed by pinhole bone scintigraphy. This paper describes characteristic pinhole scintigraphic findings of SCCH, with comparative study with radiographic and pathologic findings.

• Journal of the Korean Society of Safety
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• v.29 no.5
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• pp.74-81
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• 2014

This study proposes an advanced type of a micropile system. The proposed micropile system consists of perfobond ribs installed steel rod to improve shear capacity between the thread and the grout, and partially expanded drill holes to increase resistance capacity between the grout and the ground. This study contains experimental evaluations on the proposed micropile system to verify the shear capacity of perfobond rib installed on the steel rod and the load-carrying capacity of shear key created by the partially expanded drill hole. Push-out tests were conducted on a rolled screw thread and steel rods which perfobond ribs are installed instead of rolled screw, in order to compare their load-carrying capacity and behavioral characteristics. As a result, it was confirmed that the perfobond-rib steel rods show much superior structural behavior in terms of initial stiffness, ultimate load, and ductile behavior.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1364-1367
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• 2007

In this study, the effect of binder polymer on the photolithographic patterning of barrier ribs was studied from view point of polymer structure and barrier rib pattern.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.1
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• pp.33-42
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• 1999

The effects of wan thermal boundary condition were investigated for a uniform wall temperature, a uniform wall heat flux, and for coupled heat conduction In the channel wall with transverse rectangular ribs. Numerical investigations for steady laminar flow show behavior similar to that observed experimentally in the separated flow region for flow over a cylinder. Conjugate heat transfer with a low solid-fluid thermal conductivity ratio does not lead to the same results as for the uniform heat flux boundary condition, and heat transfer reversal is found on the back sides of the ribs.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.142-145
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• 2006

A method of plane expansion of reinforced concrete apartments using precast concrete was developed. The method increased the stiffness of the precast slab using two ribs and allowed to cast concrete for multi stories. The proposed precast system is capable to construct concrete slabs without props. Ten reinforced concrete slabs were tested in order to investigate the stiffness increase of the developed precast slab with two rids. Comparison between the proposed precast slab and the slab without ribs indicated that the deflection of the precast slab was decreased by using rids.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.989-992
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• 2008

X-ray lithography is one of the most powerful processes in the fabrication of nano/micro structures with a high aspect ratio. This process enables the fabrication of ultra-thin barrier ribs for PDP using X-ray sensitive paste. In this paper, organic material including photo-monomers, photo-oligomers, binder polymer and additives as well as inorganic powders with different size were optimized to fabricate high aspect ratio barrier rib pattern for PDP.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.935-937
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• 2006

Phosphate glass system is expected to be useful as a lead-free material in many devices in plasma display panels (PDP). The present study is mainly focused on the evaluation of interface reaction between ceramic fillers and phosphate glass matrix for barrier ribs in PDP. The results suggest that properties of barrier rib depend on the crystallization behavior and interface reaction between the fillers and glass matrix.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.938-941
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• 2006

It is suggested that the bismate glass system is one of alternatives to the lead glass for barrier-ribs in PDP. Moreover it is necessary to investigate the resultant change in properties with addition of ceramic fillers. Glass frit was selected to be a $Bi_2O_3-ZnO-B_2O_3-Al_2O_3$ and two fillers, ZnO and $Al_2O_3$ were added into a glass matrix with the different content. We investigated thermal, chemical properties of bismate glass system with two different fillers. We confirmed that addition of fillers effects properties of composites such as the thermal expansion coefficient, etching mechanism.

• 한국전산유체공학회:학술대회논문집
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• 2003.10a
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• pp.237-239
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• 2003

The present study investigates on design optimization of rib-roughened two-dimensional channel to enhance turbulent heat transfer. Response surface method with Reynolds-averaged Navier-Stokes analysis is used as an optimization technique. Standard $k-{\varepsilon}$model with wall functions is adopted as a turbulence closure. The objective function is defined as a linear combination of heat transfer and friction drag coefficients with weighting factor. Computational results for overall heat transfer rate show good agreements with experimental data. Four design variables are optimized for weighting factor of 0.02.