• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.187-188
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• 2000

The conventional firing process method for the transparent dielectric layer in PDP Technology has disadvantages of low through put, high power consumption and large process area. We propose the rapid thermal scinterring (RTS) method as new process method to overcome these disadvantage characteristics. As the experimental result of this method, the optic transmittance(wavelength : 600nm) rate of transparent dielectric layer was more improved than conventional furnaces under the optimized gas supplying. Further, it was certified this method had the best conditions on the firing process of the PDP transparent dielectric layer.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.10
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• pp.441-446
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• 2003

The chemical mechanical polishing (CMP) process is now widely employed in the ultra large scale integrated (ULSI) semiconductor fabrication. Especially, shallow trench isolation (STI) has become a key isolation scheme for sub-0.13/0.10${\mu}{\textrm}{m}$ CMOS technology. The most important issues of STI-CMP is to decrease the various defects such as nitride residue, dishing, and tom oxide. To solve these problems, in this paper, we studied the planarization characteristics using slurry additive with the high selectivity between $SiO_2$ and $Si_3$$N_4$ films for the purpose of process simplification and in-situ end point detection. As our experimental results, it was possible to achieve a global planarization and STI-CMP process could be dramatically simplified. Also, we estimated the reliability through the repeated tests with the optimized process conditions in order to identify the reproducibility of STI-CMP process.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2003.10a
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• pp.196-200
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• 2003

A novel prepurification method was developed aiming at increasing yield and purity, also reducing solvent usage for purification of paclitaxel. The use of a micelle and precipitation in the prepurification process allows for rapid separation of paclitaxel from interfering compounds and dramatically reduces solvent usage compared to alternative methodologies. The prepurification process serves to minimize the size and complexity of the HPLC operations for paclitaxel purification. The process is readily scalable to a pilot plant and eventually to a production environment where multikilogram quantities of material are expected to be produced. As much as possible, the process has been optimized to minimize solvent usage, complexity, and operating costs.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.501-504
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• 1999

In the shallow trench isolation(STI) chemical mechanical polishing(CMP) process, the key issues are the optimized thickness control within- wafer-non-uniformity, and the possible defects such as nitride residue and pad oxide damage. These defects after STI CMP process were discussed to accomplish its optimum process condition. To understand its optimum process condition, overall STI related processes including reverse moat etch, trench etch, STI filling and STI CMP were discussed. It is represented that the nitride residue can be occurred in the condition of high post CMP thickness and low trench depth. In addition there are remaining oxide on the moat surface after reverse moat etch. It means that reverse moat etching process can be the main source of nitride residue. Pad oxide damage can be caused by over-polishing and high trench depth.

• Transactions of Materials Processing
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• v.21 no.1
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• pp.42-48
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• 2012

Hydroforming has attracted the attention of manufacturing industries for vehicles and transportation systems. A wide range of products such as subframes, camshafts, radiator frames, axles and crankshafts are made by the hydroforming process. Hydroformed parts often need to be structurally joined to other components during assembly. Therefore it is useful if the hydroformed automotive parts can be attached with a localized flange. In this study, a hydroforming process to produce a rectangular shape flange is proposed. FE analysis to form the flanged rectangular shape was performed by Dynaform 5.5. The hydroforming characteristics at various die aspect ratios and feeding conditions were analyzed and optimal process conditions which can avoid defects are suggested. For validation purposes, hydroforming experiments to form the flange were conducted with the optimized conditions. The results show that the flanged parts can be successfully formed with a hydroforming process without additional processing steps.

• International Journal of Advanced Culture Technology
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• v.9 no.4
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• pp.417-423
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• 2021

Recently, in the Game industries, they are increasing to use of game engines to reduce the development cost of 3D content and software. In particular, Unreal Engine provides a blueprint visual scripting function that enables software production without programming (coding). Although High-end video content can be produced, the problem is that content development is complicated and requires advanced manpower. To solve this problem, we propose an optimized VR game context process. This is because 1) a Blueprint visual script is used, 2) VR games with various interactions can be produced, 3) Non-majors in the software field (or groups) can develop advanced content. In various related industries such as defense, medical care, manufacturing, and construction, we may easily develop any game content without programming with our refined VR rhythm action game development process. We expect to reduce the development cost with the process advantages in the game industries.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.11
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• pp.82-91
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• 1996

In this study, we put our object to carry out adaptive modeling of cutting process in turning system, and to find out the optimal cutting conditions to maximize material removal rate under some constraints. We used a back-propagation neural network to model the cutting process adaptively and a genetic algorithm to find out optimal cutting conditions. The experimental results show that a back-propagation neural network could model the cutting process effciently, and optimized cutting conditions for maximizing the material removal rate were obtained through the adaptive process model and genetic algorithms. Therefore, the proposed approach can be applied to the real machining system.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.1
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• pp.27-33
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• 2005

In this study, the process parameters in ceramics powder compaction are optimized for getting high relative densities of ceramic products. To find optimized parameters, the analytic models of powder compaction are firstly prepared by 2-dimensional rod arrays with random green densities using a quasi-random multiparticle array. Then, using finite element method, the changes in relative densities are analyzed by varying the size of Al₂O₃ particle, the amplitude of cyclic compaction, and the coefficient of friction, which influence the relative density in cyclic compactions. After the analytic function of relative density associated process parameters are formulated by aid of the response surface method, the optimal conditions in powder compaction process are found by the grid search method. When the particle size of Al₂O₃ is 22.5 ㎛, the optimal parameters for the amplitude of cyclic compaction and the coefficient of friction are 75 MPa and 0.1103, respectively. The maximum relative density is 0.9390.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.567-572
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• 2013

In houses that use heating and cooling system, most of heat loss occurs through the windows, so that low-E glass, double-layered glass, and vacuum glazing are used to minimize the heat loss. In this paper, an encapsulating process that is a final process in manufacturing the vacuum glazing has been studied, and bonding in a vacuum chamber rather than atmospheric bonding was considered. For the efficiency of the encapsulating process, frit-melting temperature and bonding time were optimized with heater temperature, and the glass preheating temperature was optimized to prevent glass breakage due to thermal stress. Thus the vacuum glass was successfully manufactured based on these results and heat transmission coefficient measured was about $5.7W/m^2K$ which indicates that the internal pressure of the vacuum glazing is $10^{-2}$ torr.

• Progress in Superconductivity
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• v.13 no.2
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• pp.133-138
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• 2011

To reduce the processing cost of the single grain REBCO (RE: Rare-earth elements) bulk superconductors, a cost-effective process should be developed. One possible way of developing the cost-effective process is the use of low-cost precursor powders. In this study, the single grain YBCO superconductors were fabricated using a home made powder. $YBa_2Cu_3O_{7-y}$ (Y123) powders were synthesized at $850-900^{\circ}C$ in air by the powder calcination method with repeated crushing and heat treatment steps. The processing parameters for the fabrication of single grain Y123 bulk superconductors, $T_{max}$ (maximum temperature), $T_p$ (peritectic temperature) and a cooling rate through $T_p$ were optimized. To enhance the flux pinning capacity of the single grain Y123 samples, $Y_2BaCuO_5$ (Y211) particles were dispersed in the Y123 matrix by adding $Y_2O_3$ powder to the calcined Y123 powder. Applying the optimized processing condition, the single grain Y123 superconductors with $T_c=91\;K$ and $J_c=1.5{\times}10^4\;A/cm^2$ at 2 T were successfully fabricated using a home made powder. The levitation forces and trapped magnetic field at 77 K measured using a Nd-B-Fe permanent magnet of 5300 G were 47 N and 3000 G, respectively, which are comparable to those obtained for the samples fabricated using a commercial grade Y123 powders.