• Journal of the Korean Mathematical Society
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• v.53 no.1
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• pp.1-17
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• 2016

Let $\mathcal{W}$ be an additive full subcategory of the category R-Mod of left R-modules. We provide a method to construct a proper ${\mathcal{W}}^H_C$-resolution (resp. coproper ${\mathcal{W}}^T_C$-coresolution) of one term in a short exact sequence in R-Mod from those of the other two terms. By using these constructions, we introduce and study the stability of the Gorenstein categories ${\mathcal{G}}_C({\mathcal{W}}{\mathcal{W}}^T_C)$ and ${\mathcal{G}}_C({\mathcal{W}}^H_C{\mathcal{W}})$ with respect to a semidualizing bimodule C, and investigate the 2-out-of-3 property of these categories of a short exact sequence by using these constructions. Also we prove how they are related to the Gorenstein categories ${\mathcal{G}}((R{\ltimes}C){\otimes}_R{\mathcal{W}})_C$ and ${\mathcal{G}}(Hom_R(R{\ltimes}C,{\mathcal{W}}))_C$ over $R{\ltimes}C$.

• Journal of the Semiconductor & Display Technology
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• v.2 no.3
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• pp.1-6
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• 2003

In the rapid changes of the semiconductor manufacturing technologies for early 21st century, it may be safely said that a kernel of terms is the size increase of Si wafer and the size decrease of semiconductor devices. As the size of Si wafers increases and semiconductor device is miniaturized, the units of cleaning processes increase. A present cleaning technology is based upon RCA cleaning which consumes vast chemicals and ultra pure water (UPW) and is the high temperature process. Therefore, this technology gives rise to environmental issue. To resolve this matter, candidates of advanced cleaning processes have been studied. One of them is to apply the electrolyzed water. In this work, electrolyzed water cleaning was compared with various chemical cleaning, using Si wafer surfaces by changing cleaning temperature and cleaning time, and especially, concentrating upon the contact angle. It was observed that contact angle on surface treated with Electrolyzed water cleaning was $4.4^{\circ}$ without RCA cleaning. Amine series additive of high pKa (negative logarithm of the acidity constant) was used to observe the property changes of cathode water.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.729-732
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• 2008

Naphthalenic admixture(PNS) has been widely used as main component of AE reducing agent among superplasticizers for concrete for a long time. However its noxiousness has been appointed because of formaldehyde compound applied during in synthetic process. In this study, AE reducing agent prepared using PNS and substituted-PNS agent(ECO-AEM) without formaldehyde compound added to concrete. For these agent, the basic performance of concrete and ecological affinity properties were evaluated and compared.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.814-817
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• 2003

As additive Pt of a little to $SnO_2$ that gas sensing property is superior oxide-semiconductor material to fabricate gas sensor that operation is possible at room temperature and fabricated ceramic gas sensing devices. And, the change amount and sintering temperature of addition material investigated gas sensitivity by change of operation temperature, humidity relativity, Long-term stability and hysteresis. And achieved SEM and XRD analysis for characteristics searching examination of devices.

• Carbon letters
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• v.11 no.2
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• pp.117-121
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• 2010

The composites of alginate, carbon nanotube, and iron(III) oxide were prepared for the removal of heavy metal in aqueous pollutant. Both alginate and carbon nanotube were used as an adsorbent material and iron oxide was introduced for the easy recovery after removal of heavy metal to eliminate the secondary pollution. The morphology of composites was investigated by FE-SEM showing the carbon nanotubes coated with alginate and the iron oxide dispersed in the alginate matrix. The ferromagnetic properties of composites were shown by including iron(III) oxide additive. The copper ion removal was investigated with ICP AES. The copper ion removal efficiency increased greatly over 60% by using alginate-carbon nanotube composites.

• ETRI Journal
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• v.38 no.2
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• pp.252-259
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• 2016

Di(1-aminopyrene)quinone (DAQ) as a quinone-containing conducting additive is synthesized from a solution reaction of 1-aminopyrene and hydroquinone. To utilize the conductive property of DAQ and its compatibility with activated carbon, a composite electrode for a supercapacitor is also prepared by blending activated carbon and DAQ (3:1 w/w), and its supercapacitive properties are characterized based on the cyclic voltammetry and galvanostatic charge/discharge. As a result, the composite electrode adopting DAQ exhibits superior electrochemical properties, such as a higher specific capacitance of up to $160F{\cdot}g^{-1}$ at $100mV{\cdot}s^{-1}$, an excellent high-rate capability of up to $1,000mV{\cdot}s^{-1}$, and a higher cycling stability with a capacitance retention ratio of 82% for the 1,000th cycle.

• Journal of applied mathematics & informatics
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• v.20 no.1_2
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• pp.445-454
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• 2006

We describe a solution to the Ornstein-Uhlenbeck equation $\frac{dI}{dt}-\frac{1}{\tau}$I(t)=cV(t) where V(t) is a constant multiple of a Gaussian white noise. Our solution is based on a discrete set of Gaussian white noise obtained by taking sample points from a sum of single frequency harmonics that have random amplitudes, random frequencies, and random phases. Hence, it is different from the solution by the standard random walk using random numbers generated by the Box-Mueller algorithm. We prove that the power of the signal has the additive property, from which we derive that the Lyapunov characteristic exponent for our solution is positive. This compares with the solution by other methods where the noise is kept to be in an error range so that its Lyapunov exponent is negative.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.173-176
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• 2006

The effect of enzymatically hydrolyzed vital wheat gluten (EHG) on dough mixing and the baking quality of wheat flour frozen dough was examined. Three different proteases, pepsin, trypsin, and chymotrypsin, were tested individually, sequentially paired, or in combination of all three enzymes. Addition of 1% EHG produced no observable effect on the mixing properties of wheat flour dough. However, addition of 2.5% pepsin-hydrolyzed gluten decreased the mixing tolerance of the wheat flour, and 1% trypsin-hydrolyzed gluten increased the loaf volume of both frozen and non-frozen dough. This finding suggests that trypsin-hydrolyzed vital wheat gluten may serve as a baking additive in replacement for $KBrO_3$ to improve frozen dough quality.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.389-391
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• 1995

Using as an alternate of insulating material for outdoor and cable, however, it has still many problems to be solved in the field of material such as resistances of environment and tracking. In this paper, Tracking property of PVC filled with aluminum hydroxide have been investigated by ASTM D 2303 method. It was found that time to track of PVC filled aluminum hydroxide was longer than that of unfilled PVC. Tensile strength and elongation of PVC were decreases increased with aluminum hydroxide contents. On the other hand, Thermegravimetry of PVC decreased. Therefore, the increase of time to tracking breakdown by antitracking additive can be explained by increased degradation temperature of polymer.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.5
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• pp.853-860
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• 2001

This paper presents the new two denoising methods using wavelet. One is new spatially selective noise filtration(NSSNF) using spatial correlation and the other is undecimated discrete wavelet transform (UDWT) threshold-based. NSSNF got the flexible gain special property of SNR adding new parameter at the existing SSNF and UDWT had superior denosing effect than orthogonal wavelet transform(OWT) applied soft-threshold by applied hard-threshold. We selected additive white gaussian noise(AWGN) in this test environment. Also we analyzed and compared ousting denoising method using SNR as standard of judgement of improvemental effect.