• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.3
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• pp.224-229
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• 2016

Recently, polymeric micro-fluidic biochips with numerous micro patterns on the surface were fabricated by injection molding for realizing low-cost mass production of devices. To evaluate the effects of process parameters on large-scale micro-structure replication, a $50{\times}50mm^2$ tool insert with surface structures having a patterns of trapezoidal shapes (height: $30{\mu}m$) was employed. During injection molding, PMMA was used; packing phase parameters and mold temperature were investigated. The replicated surface textures were quantitatively characterized by confocal laser microscopy with 10-nm resolution. The degree of replication at low mold temperatures was found to be higher than that at high mold temperature at the beginning of the packing stage. Thereafter, the degree of replication increased to a greater extent at higher mold temperatures; application of higher mold temperatures improved the degree of replication.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.45-50
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• 2014

A fully packed capillary electrochromatographic (CEC) microchip with an on-column micro-solid phase extraction (SPE) bed for the preconcentration and separation of organic analytes was prepared. A linear microchannel with monodisperse colloidal silica packing was formed on a cyclic olefinic copolymer microchip with two reservoirs on both ends. Silver-cemented silica packing frit structure was formed at the entrance of the microchannel by electroless plating treatment as a base layer. A gold coating was formed on it by reducing $Au^{3+}$ to gold with hydroxylamine. Finally micro-SPE bed was formed by self-assembly adsorption of 1-dodecanethiol on it. Micro-SPE beds were about 100-150 ${\mu}m$ long. Approximately $10^3$ fold sensitivity enhancements for Sulforhodamine B, and Fluorescein in nM concentration levels were possible with 80 s preconcentration. Basic extraction characteristics were studied.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.11
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• pp.139-147
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• 1999

Rapid Prototyping has made a drastic change in all industries which needs to reduce the time for the development of new products. Orientation and packing in rapid prototyping is considered as the most important factors to maximize the utilization of space in the build chamber and reduce build time. However, the decision of these parameter is mainly dependant on the operators's experience. This paper presents the methodology to find the optimal build layout considering an orientation and packing of multiple parts in SLS processing. Each part is represented as a voxel structure to deal with the inefficiency in a bounding box approach. Test results show that the adapted BL algorithm with a genetic algorithm(GA) can be applicable to a real industry.

• Journal of the Semiconductor & Display Technology
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• v.21 no.1
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• pp.62-66
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• 2022

Semiconductor is one of the most internationally competitive areas among domestic industries, the major concern of which is the stability of the wafer manufacturing processes. The packaging process is the final step in wafer manufacturing. Problems in the wafer packaging process cause large losses. The vibrations are supposed to be the most important factors for the packaging quality. In this study, the structure of a packaging box was analyzed through experiments and computer simulations, and further the effects of design alterations to suppress the vibrations have been investigated. The final result shows that the vibrations can be reduced substantially to improve the stability of the structure.

• Design & Manufacturing
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• v.16 no.3
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• pp.1-8
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• 2022

In this study, an artificial neural network(ANN) was constructed to establish the relationship between process condition prameters and the qualities of the injection-molded product in the injection molding process. Six process parmeters were set as input parameter for ANN: melt temperature, mold temperature, injection speed, packing pressure, packing time, and cooling time. As output parameters, the mass, nominal diameter, and height of the injection-molded product were set. Two learning structures were applied to the ANN. The single-task learning, in which all output parameters are learned in correlation with each other, and the multi-task learning structure in which each output parameters is individually learned according to the characteristics, were constructed. As a result of constructing an artificial neural network with two learning structures and evaluating the prediction performance, it was confirmed that the predicted value of the ANN to which the multi-task learning structure was applied had a low RMSE compared with the single-task learning structure. In addition, when comparing the quality specifications of injection molded products with the prediction values of the ANN, it was confirmed that the ANN of the multi-task learning structure satisfies the quality specifications for all of the mass, diameter, and height.

• Journal of the Korean Ceramic Society
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• v.32 no.1
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• pp.113-119
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• 1995

The green body was fabricated by a new forming method, pressureless powder packaing forming method, and the characteristics of sintered specimen were investigated. It was found that alumina ceramics prepared by the present method showed porous structure with narrow pore size distribution, and in case of abrasive powder sintered body, compared with dry-pressed specimen, had the nearly same density. Especially, the specimen prepared with spray-dried granules showed the characteristic that granules were not either deformed or fractured during forming and sintering process. Therefore, it was found that this new forming method was effective method in fabrication of porous ceramics on account of easy control of porosity and pore size and its high thermal stability.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.835-840
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• 2000

The purpose of this study is developing concrete Mixing & placing method that could be adjusted to vertical joint at top-down method. Basic test was consists of general, high fluidity, and high quality mixing concretes and Mock-up test had several placing ways, placing positions. They were examined several placing ways, placing positions with Mock-up model comparison with three mixing concrete to know fluidity characterics. Used with Mock-up model to know packing ability from placing ways and positions. The result of the study like this; High fluidity and High quality concretes show favorable packing ability, especially, in sheath placing way. It was expected to good result in next planned real structure test.

• Magazine of the Korean Society of Agricultural Engineers
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• v.43 no.5
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• pp.63-69
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• 2001

The main purpose of this study is to seek desalinization effect of subsurface drainage system with rice hull packing in Dae-Ho Reclaimed Land. After 4 years installed sub-surface drainage system, distribution of drained water electric conductivity (ECw) was 4.43~12.78 ds/m. The soil profile showed partial development of the soil structure and compaction of subsoils with increased bulk density. The bulk density of the subsoil was 1.42~1.66 g/cm$^3$, which might limit root growth. The soil color changed near the drainage pipe line. Distribution of soil extract solution ECe and SAR as subsurface drainage pipe position and drainage canal distance showed desalinization effect of subsurface drainage system with rice hull packing as widening effective zone of subsurface drainage pipe.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.1 s.343
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• pp.71-78
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• 2006

An NoC (Networks-on-Chip) is an emerging design paradigm intended to cope with a future SoC containing numerous built-in cores. In an NoC, the test strategy is very significant for its practicality and feasibility. Among existing test issues, TAM architecture and test scheduling will particularly dominate the overall test performance. In this paper, we address an efficient NoC test scheduling algorithm based on a rectangle packing approach used for an SoC test. In order to adopt the rectangle packing solution as an NoC test scheduling algorithm we design the configuration about test resources and test methods suitable for an NoC structure. Experimental results using some ITC'02 benchmark circuits show the proposed algorithm can reduce the overall test time by up to $55\%$ in comparison with previous works.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.4
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• pp.41-48
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• 2000

The main objective of this study was to investigate the packing state and optical properties of coated paper prepared with different coating colors by varying the blending ratio of such pigment as clay, $CaCO_3$, and plastic pigment. To evaluate the effect of packing state of pigment on the properties of coated paper, the coating thickness, which was theoretically calculated by specific gravity, and packing volume of pigment were used. It was found that there exists close relationship between the coating thickness and surface property of coated paper. For instance, the macro roughness(smoothness) of coated paper is closely related to bulkiness. Plastic pigments used in this research has a high finishing efficiency on the light weight coatings. Especially, hollow sphere pigment was very effective for improving the property of coated paper produced in this test. And when HSP was blended with $CaCO_3$the surface property such as smoothness and gloss improved significantly.