• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.30-34
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• 1997

This paper Describe a modelling method for SCR(selective Catalytic reduction) system in refuse incineration plant. We consider the SCR system as a single input single output system. For modelling the SCR system, an auto regressive exogeneous(ARX) modelling method is used. In this case, we should design the white noise input for modelling and put it on the system as an input (.NH/sap2/.), and taken an outlet NOx as an output. From these two relations, we design the ARX model with 45 second delay time and transform to discrete system with 0.5 sampling time. Using the obtained SCR model, we simulate the SCR system to reduce the outlet NOx content by a conventional PID control method.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2001.05a
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• pp.187-191
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• 2001

In the paper, an approach to the development of the selective catalytic reduction process of NOx is presented. The reduction process can be efficiently controlled using a conventional combination of feed-forward and feed-back control structures. The aim of this paper is to test and verify an approach to the SCR process which is based on an industrial pilot plant of combustion and nitric oxide formation. The systems are based on measurements of a NOx removal ratio and the fuel flow rate, and NH$_3$slip which are usually available as a part of de-NOx control system.

• Journal of the Semiconductor & Display Technology
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• v.17 no.4
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• pp.16-20
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• 2018

Graphene is attracting attention due to its outstanding properties as line material for next-generation semiconductor. Graphene pattern technology is essential to apply graphene line. Selective graphene oxide reduction as one of graphene pattern method does not require a substrate thereby a high flexibility device can be applied. Particularly, the method using photon energy has advantages of short process time and environment friendly. In this review, we introduce the photocatalytic method and the photo-thermal energy conversion method using photon energy in the selective reduction process of graphene oxides.

• Applied Chemistry for Engineering
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• v.23 no.6
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• pp.588-593
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• 2012

In this study, selective catalytic reduction (SCR) reaction was performed using liqufied petroleum gas (LPG) as a reductant for removing NOx. The catalysts were manufactured with different amounts of Cu and Fe supported on HZSM-5 in order to remove NOx. The NOx conversion ratio was studied with changing the temperature and the catalyst amount. The catalysts were manufactured by calcination with flowing the ambient air at $500^{\circ}C$ for three hours. Cupper of 1~4 wt% and iron of 0.5~2 wt% were supported on HZSM-5 of which Si/Al ratio were 80. According to the reaction results, the catalyst which Cu of 3 wt% supported on HZSM-5 showed the highest conversion rate. XRD, XPS, and TPR analysis were also performed for the characterization of catalysts.

• Journal of Integrative Natural Science
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• v.1 no.3
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• pp.192-194
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• 2008

A series of non-free hydride reducing systems containing boron or aluminum atom, which possess no metal-hydride bond but an available hydrogen at a branched ${\beta}$-position, has been applied to the selective reduction (chemo--, regio-, and stereoselective reduction) of organic compounds. The systems, comprised of diisopinocampheylborane and diisobutylalane derivatives, exhibited almost perfect selectivities in the reduction of aldehydes and ketones. The characteristics features of this systems leading to a perfect transformation have been depicted in this report, especially in the 1) Reduction of ${\alpha}$,${\beta}$-Unsaturated Carbonyl Compounds to Allylic Alcohols via 1,2-Reduction, 2) Chemoselective Reduction between Structurally Different Carbonyl Compounds, and 3) Stereoselective Reduction of Cyclic Ketones.

• Bulletin of the Korean Chemical Society
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• v.25 no.5
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• pp.603-604
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• 2004

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2002.05a
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• pp.187-191
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• 2002

The exhaust gas from electric power stations, incinerators and industrial boilers contains considerable amount of harmful nitric oxide which causes air pollution. Selective catalytic reduction system with ammonia as a reductant(NH$_{3}$ SCR) have been applied to remove NOx since 1970. it is widely accepted that the NH$_{3}$ SCR process is the best method for the removal of NOx. In this paper the design of SCR reactor based on the NOx displacement is considered and the design program of SCR reactor is developed. The newly developed design program for de-NOx system maybe used in practice.

• Bulletin of the Korean Chemical Society
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• v.17 no.1
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• pp.50-55
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• 1996

Reaction of carbonyl compounds with diisopinocampheylhaloboranes (Ipc2BX,X=Cl, Br, I) was investigated in detail in order to establish their usefulness as selective reducing agents. The reagents reduced aldehydes and ketones to the corresponding alcohols. The reactivities are in the order of Ipc2BCl Ipc2BBr>Ipc2BI.The reagents also reduced ${\alpha}{\beta}-unsaturated$, aldehydes and ketones to the corresponding allylic alcohols without any detectable 1,4-reduction. Especially, the chloro derivative nicely achieved the selective reduction of aldehyde or ketone groups in the presence of many other functional groups. The most remarkable result of this investigation is that aldehydes and ketones can be selectively reduced in the presence of acid chlorides.

• Bulletin of the Korean Chemical Society
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• v.22 no.5
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• pp.488-492
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• 2001

As gas chromatography/infrared spectrometry (GC/IR) becomes routinely avaliable, methods must be developed to deal with the large amount of data produced. We demonstrate computer methods that quickly search through a large data file, locating thos e spectra that display a spectral feature of interest. Based on a modified library search routine, these selective data reduction methods retrieve all or nearly all of the compounds of interest, while rejecting the vast majority of unrelated compounds. To overcome the shifting problem of IR spectra, a search method of moving the average pattern was designed. In this moving pattern search, the average pattern of a particular functional group was not held stationary, but was allowed to be moved a little bit right and left.

• Perinatology
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• v.29 no.4
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• pp.180-184
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• 2018

In assisted reproductive techniques, monozygotic twinning is not influenced by the trial of reducing the number of embryos transferred. We present extremely rare case of monochorionic triamniotic triplet pregnancy following in vitro fertilization and two-embryo transfer. During the first trimester, the crucial ultrasound findings of monochorionic triamniotic triplet pregnancy are three distinct amniotic sacs forming a triangle or ipsilon zone within a single chorionic cavity. After prudential counseling about the potential risk of a monochorionic triamniotic triplet pregnancy with the patient, selective reduction of two fetuses via radiofrequency ablation was performed. We report a case of selective reduction for monochorionic triamniotic triplet pregnancy using radiofrequency ablation at 12 weeks' gestation and obstetric progression after radiofrequency ablation was uneventful until 20 weeks' gestation.