• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.657-660
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• 2009

Optically compensated bend (OCB) mode has intrinsic characteristics such as wide viewing angle and fast response time. However, in order to operate the OCB mode in bend state, this device needs quick transitions from the initial splay state to bend state. In this paper, we proposed OCB mode with initially bend state using reactive mesogen (RM) monomer for surface polymer stabilization. The device shows continuous reorientation of the LC with applied field and a very fast response time.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.39-40
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• 2009

The patterned vertical alignment (PVA) display showed good electro-optic properties such as wide viewing angle, fast response time, high Contrast Ratio. However, the device has patterned electrode on both top and bottom electrodes which requires high accuracy of assembling of top and bottom substrates in order to exhibit a high performance. So, they have disadvantage about low yield. In order to resolve these problem, in this paper, we studied about top substrate pattern free vertical alignment device associated with surface polymer stabilization using the UV curable monomer. This method shows simple progress, low cost and good electro-optic properties such as high transmittance and fast response time.

• Geomechanics and Engineering
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• v.23 no.2
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• pp.103-113
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• 2020

Gypsiferous soils classified as problematic soils due to the dissolution of gypsum. Presence of gypsum in the soils texture subjected to steady flow can cause serious damages for the buildings, roads and water transmission canals. Therefore, researchers have conducted a series of physical, mechanical and microstructural laboratory tests to study the effect of gypsum leaching on the geotechnical properties of a lean clay containing 0%, 3%, 6%, 9%, 12%, and 15% raw gypsum. In addition, a combination of two nano-chemical stabilizers named Terrasil and Zycobond was used in equal proportions to stabilize the gypsiferous clayey samples. The results indicated that gypsum leaching considerably changed the physical and mechanical properties of gypsiferous soils. Further, adding the combination of Terrasil and Zycobond nano-polymeric stabilizers to the gypsiferous soil led to a remarkable reduction in the settlement drop, compressibility, and electrical conductivity (EC) of the water passing through the specimens, resulting in improving the engineering properties of the soil samples. The X-ray diffraction patterns indicate that stabilization by terrasil and zycobond causes formation of new peaks such as CSH and alteration of pure soil structure by adding raw gypsum. Scanning electron microscope (SEM) images show the denser texture of the soil samples due to chemical stabilization and decrease of Si/Al ratio which indicates by Energy dispersive X-ray (EDS) interpretation, proved the enhance of shear strength in stabilized samples.

• Bulletin of the Korean Chemical Society
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• v.31 no.1
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• pp.234-237
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• 2010

• Advances in nano research
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• v.17 no.2
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• pp.125-136
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• 2024

In the present research the durability and geotechnical properties of an expensive clayey soil stabilized by two different compositions of additives were investigated and compared. The first composition consisted of environmentally and ecofriendly materials: BOF steel slag ranging from 0-20% as well as rice husk ash (RHA) ranged 0-16%wt of dry soil. The other composition consisted of relatively new generation of materials including nanomaterials: nano-CaCO3 as well as nano-SiO2. Atterberg limits test, free swell percent test, swelling pressure test and unconfined compressive test were used to assess the stabilizers influences upon expansive soil geotechnical characteristics. Also, the recurrent wet-dry cycles test was exerted on experimental and non-experimental samples for estimating stabilizers effects on durability. According to the results, each of the BOF slag and RHA enhances the expansive soil properties individually, while combination of slag-RHA led to better improvement of the soil properties. Also, the composition of nano-CaCO3 and SiO2 dramatically improved the clay soil operation. The optimum values of slag+RHA were suggested as 20% slag+12% RHA to enhance percent of swelling, pressure of swelling in addition to UCS as much as 95%, 96%, and 370%, respectively. The optimum value for the second stabilizer in this study was found to be 2%nano-SiO2+2% nano-CaCO3 which led to 318% increase in UCS and 86% decrease in swelling pressure.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2913-2917
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• 2009

Second-order rate constants (k$_{Nu–}$) have been measured for nucleophilic substitution reactions of Y-substituted phenyl benzoates (1a-i) with butane-2,3-dione monoximate ($Ox^-\;an\;\alpha$-nucleophile) and Z-substituted phenoxides in 80 mol% H$_2$O/20 mol% DMSO at 25.0${\pm}$0.1$^{\circ}C$. Hammett plots correlated with ${\sigma}^o$ and ${\sigma}^-$ constants for reactions of 1a-h with Ox$^–$ exhibit many scattered points. In contrast, the Yukawa-Tsuno plot results in a good linear correlation with ${\rho}_Y$ = 2.20 and r = 0.45, indicating that expulsion of the leaving group occurs in the rate-determining step (RDS). A stepwise mechanism with expulsion of the leaving-group being the RDS has been excluded, since Y-substituted phenoxides are less basic and better nucleofuges than Ox$^–$. Thus, the reactions have been concluded to proceed through a concerted mechanism. Ox$^–$ is over 10$^2$ times more reactive than its reference nucleophile, 4-chlorophenoxide (4-ClPhO$^–$). One might suggest that stabilization of the transition-state (TS) through intramolecular general acid/base catalysis is responsible for the ${\alpha}$-effect since such general acid/base catalysis is not possible for the corresponding reactions with 4-ClPhO$^–$. However, destabilization of the ground-state (GS) of Ox$^–$ has been concluded to be mainly responsible for the ${\alpha}$-effect found in this study on the basis of the fact that the magnitude of the ${\alpha}$-effect is independent of the nature of the substituent Y.

• Journal of Environmental Impact Assessment
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• v.29 no.5
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• pp.350-362
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• 2020

In this study, nano Fe°-impregnated biochar (INPBC) was prepared using pruning residues and one-pot synthetic method and evaluated its performance as an amendment agent for the stabilization of arsenic-contaminated soil. For the preparation of INPBC, the mixture of pruning residue and Fe (III) solution was heated to 220℃ for 3hr in a teflon-sealed autoclave followed by calcination at 600℃ under N₂ atmosphere for 1hr. As-prepared INPBC was characterized using FT-IR, XRD, BET, SEM. For the stabilization test of as-prepared INPBC, As-contaminated soils (Soil-E and Soil-S) sampled from agricultural sites located respectively near E-abandoned mine and S-abandoned mine in South Korea were mixed with different of dosage of INPBC and cultivated for 4 weeks. After treatment, TCLP and SPLP tests were conducted to determine the stabilization efficiency of As in soil and showed that the stabilization efficiency was increased with increasing the INPBC dosage and the concentration of As in SPLP extractant of Soil-E was lower than the drinking water standard level of Ministry of Environment of South Korea. The sequential fractionation of As in the stabilized soils indicated that the fractions of As in the 1st and 2nd stages that correspond liable and known as bioavailable fraction were decreased and the fractions of As in 3rd and 4th stages that correspond relatively non-liable fraction were increased. Such a stabilization of As shows that the abundant nano Fe° on the surface of INPBC mixed with As-contaminated soils played the co-precipitation of As leaching from soil by surface complexation with iron. The results of this study may imply that INPBC as a promising amendments for the stabilization of As-contaminated soil play an important role.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2002.04b
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• pp.51-51
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• 2002

• Korean Journal of Metals and Materials
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• v.48 no.9
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• pp.831-841
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• 2010

Indium tin oxide (ITO) nanopowders were synthesized by coprecipitation and the sol-gel method to prepare a stable dispersion of ITO nano-colloid for antistatic coating of a display panel. The colloidal dispersions were prepared by attrition process with a vibratory milling apparatus using a suitable dispersant in organic solvent. The ITO coating solution was spin-coated on a glass panel followed by the deposition of partially hydrolyzed alkyl silicate as an over-coat layer. The double-layered coating films were characterized by measuring the sheet resistance and reflectance spectrum for antistatic and antireflective properties.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.3
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• pp.288-293
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• 2016

Electronic Image Stabilization(EIS) is widely used as a technique for correcting a shake of an image. The case requiring the EIS function has been increased in high magnification thermal image observation on portable military equipment. Projection Algorithm(PA) for EIS is easy to implement but its performance is sensitive to the projection area. Especially, projection profiles of thermal image have very modest change and are difficult to extract image shifts between frames. In this paper, we proposed algorithm to extract a feature image for the thermal image and compared Block Matching Algorithm(BMA) with PA using our proposed feature image. When using our proposed feature image, BMA was simply implemented using FPGA's internal small memory. And we were able to obtain 30 % PSNR improved results compared to PA.