• Journal of the Korean Chemical Society
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• v.54 no.4
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• pp.414-418
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• 2010

Ethyl 1-aminotetrazole-5-carboxylate (1) reacted with hydrazine hydrate to give the corresponding aminohydrazide 2. Cyclization of 2 by carbon disulfide yielded 1,3,4-oxadiazole-5-thiol structure 3. Reaction of 3 with either chloroacetone or ethyl chloroacetate furnished S-acyl 1,3,4-oxadiazole derivatives 4 and 5, respectively. Also compound 3 reacted with hydrazine hydrate afforded 4-amino-1,2,4-triazole-5-thiol derivative 6. 6-Methyl-1,3,4-triazolo[3,4-b]-1,3,4-thiadiazole structure 7 was synthesized by reaction of aminothiol 6 with glacial acetic acid. Diazotization of 1 with sodium nitrite in presence of hydrochloric acid yielding the diazonium salt which on treating with hippuric acid, oxazolone derivative 8 was obtained. Furthermore, tetrazolo[5,1-f]-1,2,4-triazine 9 was constructed via cyclization of aminoester 1 with formamide. Compound 9 reacted with carbon disulfide to furnish 8-thione derivative 10 which reacting with chloroacetone, ethyl chloroacetate, and hydrazine hydrate, the corresponding chemical structures 11, 12, and 13 were synthesized. 1,2,4-Triazolo[4,3-d]tetrazolo[5,1-f]-1,2,4-triazines 14 and 15 were resulted by treating of compound 13 with triethyl orthoformate, and glacial acetic acid, respectively. The structures of the newly synthesized products were elucidated according to elemental analyses and spectroscopic evidences. Some of the representative members of the prepared compounds were screened for antimicrobial activity.

• Journal of Hydrogen and New Energy
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• v.15 no.4
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• pp.283-290
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• 2004

The single-step process for conversion of syngas to DME give higher conversion than the syngas-to-methanol process. This arises because of a synergy among the three simultaneous reaction, methanol synthesis, methanol dehydration and water gas shift reaction, in the process. we would find the optimal condition of the process which these advantages. The optimal condition of DME synthesis reaction over a commercial $Cu/Zn/Al_2O_3$ catalyst and Hybrid catalyst in a fixed bed reactor. The syngas-to-dimethyl ether conversion was examined on various reaction condition (Temperature 473~553K, $H_2/CO$ ratio 1~3, Pressure 30'50atm, GHSV 1000~4000).

• YAKHAK HOEJI
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• v.28 no.3
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• pp.191-195
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• 1984

A ten-step synthesis of 1, 3-di-O-acetyl-5-O-benzoyl-2-deoxy-2-fluoro-D-arabino-furanose, a versatile intermediate in the synthesis of chemotherapeutically important nucleosides, was achieved from D-glucose. This procedure affords good overall yields of products and is suitable for large scale preparations.

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.510-515
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• 1989

New nickel(II) and coppr(II) complexes of a saturated pentaaza macrobicyclic ligand $[Ni(D)]^{2+},\;[Cu(D)]^{2+},\;and\;[Cu(D)Cl]^+$, where D is 1,3,6,9,12-pentaazabicyclo[10,2,l]pentadecane, have been prepared by the template condensation reaction of tetraethylenepentamine and formaldehyde in the presence of the metal ion. The complexes contain one imidazolidine ring in the macrobicyclic ligand, D. The complexes $[Ni(D)]^{2+}\;and\;[Cu(D)]^{2+}$ have square planar geometry with 5-5-5-6 chelate ring sequence. The electronic spectra of $[Cu(D)Cl]^+$indicate that the complex has square pyramidal geometry. Synthesis, charactrization, and the spectroscopic and chemical properties of the macrobicyclic nickel(II) and copper(II) complexes are described.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.2
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• pp.63-71
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• 2012

Recently, web portals have been offering georeferenced SLI(Street-Level Imagery) services, such as Google Streetview. The SLI has a distinctive strength over aerial images or vector maps because it gives us the same view as we see the real world on the street. Based on the characteristic, applicability of the SLI can be increased substantially through conflation with other spatial datasets. However, spatial inconsistency between different datasets is the main reason to decrease the quality of conflation when conflating them. Therefore, this research aims to remove the spatial inconsistency to conflate an SLI with a widely used 2D vector map. The removal of the spatial inconsistency is conducted through three sub-processes of (1) road intersection matching between the SLI trace and the road layer of the vector map for detecting CPPs(Control Point Pairs), (2) inaccurate CPPs filtering by analyzing the trend of the CPPs, and (3) local alignment using accurate CPPs. In addition, we propose an evaluation method suitable for conflation result including an SLI, and verify the effect of the removal of the spatial inconsistency.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04c
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• pp.190-192
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• 2003

본 논문은 캘리브레이션 정보를 모르는 카메라로부터 얻은 시퀀스 영상에서 공간상에서 평면인 물체의영상 정보를 이용하여 카메라 내부 및 외부 파라미터를 추정하고, 이를 이용하여 가상의 3D 그래픽을 시퀀스 영상에 정합하는 방법을 제안한다. 제안된 방법은 기존의 방법에 비해 손쉽게 이미지에 가상의 3D 그래픽 오브젝트를 정합할 수 있으며, 눈에 보이는 정합오차를 최소화하며 DirectX와 같은 3D 그래픽 툴과 쉽게 연동이 되는 장정이 있다. 본 연구는 비디오와 같은 영상에 3D 영상을 합성하는 대화형 비디오 컨텐트 개발에 활용할 수 있을 것으로 기대된다.

• Journal of Broadcast Engineering
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• v.21 no.6
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• pp.878-888
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• 2016

This paper proposes an efficient method to remove the boundary artifacts of rendered views caused by damaged depth maps in the 3D video system. First, characteristics of boundary artifacts with the compression noise in depth maps are carefully studied. Then, the artifacts suppression method is proposed by the iterative projection onto convex sets (POCS) algorithm with setting the convex set in pixel and frequency domain. The proposed method is applied to both texture and depth maps separately during view rendering. The simulation results show the boundary artifacts are greatly reduced with improving the quality of synthesized views.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.4
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• pp.323-330
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• 2023

The skin's barrier structure is formed through the differentiation process of epidermal keratinocytes. It consists of corneocytes that are composed of keratin proteins and lipids that fill the spaces between them. During this process, the lipids such as phospholipid that made up the membrane of the basal layer cells of the epidermis are decomposed and replaced with newly synthesized components like ceramide. In this study, the effect of ginsenoside Rg3 components on the packing of the intercellular lipid structure of the skin barrier and the barrier function was confirmed. To confirm this, Rg3 components were treated during the differentiation process of 3D epidermal cells. The FT-IR and TEWL analysis on 3D epidermis showed an enhancement in the orthorhombic lipid packing and an improvement in barrier function. Additionally, in HaCaT cells, an increase in the expression of EVOL1 and EVOL4, which synthesize long-chain lipids, was detected, along with a decrease in CERS6, which synthesizes short-chain ceramide, and an increase in ACER6, which decomposes ceramide using phytosphingosine. This suggests the possibility that Rg3 affects lipid synthesis during the epidermal differentiation process, resulting in changes in barrier function.

• Journal of the Korean Chemical Society
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• v.23 no.1
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• pp.46-51
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• 1979

Condensation of 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-${\beta}$-D-glucopyranosyl bromide (2) with 1,2;3,4-di-O-isopropylidene-${\alpha}$-D-galactopyranose (3) in the presence of silver triflate and syn-collidine gave 1,2;3,4-di-O-isopropylidene-6-O-(3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-${\beta}$-D-glucopyranosyl)-${\alpha}$-D-galactopyranose (4) in $86{\%}$ yield. Cleavage of phthalimido group and de-O-acetylation with hydrazine, acetylation, and hydrolysis of isopropylidene and O-acetyl groups furnished 6-O-(2-acetamido-2-deoxy-${\beta}$-D-glucopyranosyl)-D-galactopyranose (1) with overall yield of $65.8{\%}$ starting from 3. Some other derivatives of 1 which have free hydroxyl groups at the specific position have also been prepared from 4. These compounds could be used as precursors for further glycosidation reactions.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2016.06a
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• pp.302-305
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• 2016

This paper proposes a boundary artifacts reduction method for synthesized views in 3D video system using Projection onto Convex Sets (POCS). In 3D video system, boundary artifacts are occurred in synthesized views by distorted depth map. In this paper, we analyze boundary artifacts, and show the experimental results by the proposed algorithm on various situations.