• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1505_1506
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• 2009

In this paper, micro cantilevers which are made of two different materials - fused quartz and single crystalline silicon - and have similar dimensions were fabricated and their mechanical Q-factors were evaluated to compare intrinsic damping properties of those two materials. Resonant frequencies and Q-factors were measured for the cantilevers having fixed widths and thicknesses, and different lengths. The measured Q-values are in a range of 64,000 - 108,000 for fused quartz cantilevers, and 31,000 - 35,000 for silicon cantilevers, respectively. Experimental results support high Q-factors of fused quartz compared to single crystalline silicon due to its good intrinsic damping properties.

• 대한심미치과학회지
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• 제11권2호
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• pp.33-36
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• 2002

As patients have concerned the esthetics of dental restorations, the porcelain fused to metal restorations have gain their popularity due to their strength and esthetic appearance for many years. However, metal collar in subgingival level of porcelain fused to metal restoration often causes black shadows. Inadequately positioned metal collar causes plaque depositions, gingival inflammations, black shadows, and discolorations of margin area. Those problems can be avoided by a clear finishing line, well-fabricated provisional restorations with precise margin and fine polishing, collarless porcelain fused to metal restoration, and all ceramic restoration. In this case report, collarless porcelain fused to metal restoration was used to treat cervical discoloration from old restorations.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2002년도 추계학술발표대회 논문집
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• pp.179-182
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• 2002

Rapid Prototyping (RP) technologies provide the ability to fabricate initial prototypes from various model materials. Stratasys' Fused Deposition Modeling (FDM) is a typical RP process that can fabricate prototypes out of plastic materials, and the parts made from FDM were often used as load-carrying elements. Because FDM deposits materials in about $300\mutextrm{m}$ thin filament with designated orientation, parts made from FDM show anisotropic material properties. This paper proposes an analytic model to predict the tensile strength of FDM parts. Applying the Classical Lamination Theory, which was developed for laminated composite materials, a computer code was implemented. Tsai-Wu failure criterion was added to the code to predict the failure of the FDM parts. The tensile strengths predicted by the analytic model were compared with experimental data. The data and prediction agreed reasonably well to prove the validity of the model. In addition, a web-based advisory service was developed to provide to strength prediction and design rules for FDM parts.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1344-1348
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• 2003

It is generally known to be difficult to etch a surface of a transparent material such as fused silica by conventional laser ablation in which the surface is simply irradiated with a laser beam. A lot of studies have been done to provide a method capable of efficiently etching transparent materials without defects such as cracks. One of the promising methods or the micro-machining of optically transparent materials is laser induced etching. In this study, micro-drilling of fused silica by laser induced wet etching was conducted. KrF excimer and YAG laser were used as light sources. Acetone solution pyrene and ethanol solution of rhodamine were used as etchant.

• 약학회지
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• 제35권4호
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• pp.283-287
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• 1991

Seven derivatives of 2,3-alkyl substituted N-cyanoaziridine were stereoselectively prepared from alkyl substituted alkenes and cyanamide. NMR spectral property and conformation of N-cyanoaziridine were analysed. Protons(3.34 ppm) at 2,3 position of N-cyanoaziridines are significantly deshielded in case of cyclopentyl fused N-cyanoaziridine. These protons are getting more anisotropically shielded with increasing the fused carbocycle size of N-cyanoaziridine. Therefore chemical shift for these protons are upfield shifted to 2.80 ppm in case of cyclooctyl fused N-cyanoaziridine. Their ED$_{50}$ values aganist L$_{1210}$, cell in vitro were evaluated as 0.5~8.0 $\mu$g/ml. Conformation of carbocycle of fused N-cyanoaziridine is more important to their cytotoxicity than the increment of the strain energy of 3-membered ring.

• Communications for Statistical Applications and Methods
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• 제25권5호
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• pp.513-521
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• 2018

The goal of sufficient dimension reduction (SDR) is to replace original p-dimensional predictors with a lower-dimensional linearly transformed predictor. The sliced inverse regression (SIR) (Li, Journal of the American Statistical Association, 86, 316-342, 1991) is one of the most popular SDR methods because of its applicability and simple implementation in practice. However, SIR may yield different dimension reduction results for different numbers of slices and despite its popularity, is a clear deficit for SIR. To overcome this, a fused sliced inverse regression was recently proposed. The study shows that the dimension-reduced predictors is robust to the numbers of the slices, but it does not investigate how robust its dimension determination is. This paper suggests a permutation dimension determination for the fused sliced inverse regression that is compared with SIR to investigate the robustness to the numbers of slices in the dimension determination. Numerical studies confirm this and a real data example is presented.

• 한국유기농업학회지
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• 제8권2호
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• pp.89-96
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• 2000

To reduce loss of nitrogen and generation of ammonia gas during composting, poultry manure and sawdust were mixed at the equivalent ratio and calcium chloride, fused superphosphate and vermiculite were added. Ammonia and sulfurous gas during composting, and NH4-N and NO3-N contents of composts were periodically measured. With the treatments of 0.5∼3% calcium chloride and 3% fused superphosphate, ammonia and sulfurous gas during composting significantly decreased, and especially generation of gases sharply reduced and a increase of calcium chlorde. Extractable NH4-N content in composts treasted with calcium chloride and fused superphosphate were high but extractable NO3-N markedly decreased. In conclusion, the results suggest that it is necessary the additon of 1∼3% calcium chloride or 3% fused superphosphate to reduce loss of nirogen and generation of offensive odor during composting of poultry manure mixed with sawdust.

• Current Optics and Photonics
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• 제4권6호
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• pp.524-529
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• 2020

We propose a depth-fused-type three-dimensional (3D) near-eye display implemented using a birefringent lens set that is made of calcite. By using a birefringent lens and image source (28.70 mm × 21.52 mm), which has different focal lengths according to the polarization state of the incident light, the proposed system can present depth-fused three-dimensional images at 4.6 degrees of field of view (FOV) within 1.6 Diopter (D) to 0.4 D, depending on the polarization distributed depth map. The proposed method can be applied to near-eye displays like head-mounted display systems, for a more natural 3D image without vergence-accommodation conflict.

• Communications for Statistical Applications and Methods
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• 제28권2호
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• pp.205-215
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• 2021

Sufficient dimension reduction is useful dimension reduction tool in regression, and sliced inverse regression (Li, 1991) is one of the most popular sufficient dimension reduction methodologies. In spite of its popularity, it is known to be sensitive to the number of slices. To overcome this shortcoming, the so-called fused sliced inverse regression is proposed by Cook and Zhang (2014). Unfortunately, the two existing methods do not have the direction application to large p-small n regression, in which the dimension reduction is desperately needed. In this paper, we newly propose seeded sliced inverse regression and seeded fused sliced inverse regression to overcome this deficit by adopting iterative projection approach (Cook et al., 2007). Numerical studies are presented to study their asymptotic estimation behaviors, and real data analysis confirms their practical usefulness in high-dimensional data analysis.

• Bulletin of the Korean Chemical Society
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• 제23권5호
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• pp.779-782
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• 2002