• Title/Summary/Keyword: $Ho^{3+}$

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Identification of Triterpenoids and Flavonoids from the Seeds of Tartary Buckwheat

  • Lee, Jeong Min;Lee, Ki Ho;Yoon, Young-Ho;Cho, Eun Ju;Lee, Sanghyun
    • Natural Product Sciences
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    • v.19 no.2
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    • pp.137-144
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    • 2013
  • Phytochemical constituents were isolated from the seeds of tartary buckwheat (Fagopyrum tataricum) by open column chromatography. Their structures were elucidated as ${\beta}$-sitosterol (1), ${\beta}$-sitosterol-3-O-glucoside (2), oleanolic acid (3), kaempferol (4), quercetin (5), kaempferol-3-O-rutinoside (6), and quercetin-3-O-rutinoside (7) on the basis of spectroscopic analysis including $^1H$-, $^{13}C$-NMR, and MS. To our knowledge, oleanolic acid (3) has been isolated for the first time from the seeds of Fagopyrum species. The total contents of compounds 4 - 7 were 0.500 mg/g in Daesan maemil, 0.312 mg/g in Yangjul maemil, and 2.185 mg/g in tartary buckwheat.

Three-Dimensional Shape Reconstruction from Images by Shape-from-Silhouette Technique and Iterative Triangulation

  • Cho, Jung-Ho;Samuel Moon-Ho Song
    • Journal of Mechanical Science and Technology
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    • v.17 no.11
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    • pp.1665-1673
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    • 2003
  • We propose an image-based three-dimensional shape determination system. The shape, and thus the three-dimensional coordinate information of the 3-D object, is determined solely from captured images of the 3-D object from a prescribed set of viewpoints. The approach is based on the shape-from-silhouette (SFS) technique, and the efficacy of the SFS method is tested using a sample data set. The extracted three-dimensional shape is modeled with polygons generated by a new iterative triangulation algorithm, and the polygon model can be exported to commercial software. The proposed system may be used to visualize the 3-D object efficiently, or to quickly generate initial CAD data for reverse engineering purposes, including three dimensional design applications such as 3-D animation and 3-D games.

Synthesis of New Morindaparvin A Derivatives (Ⅱ) (새로운 Morindaparvin A 유도체들의 합성 (Ⅱ))

  • Park, Si Ho;Rho, Young S.;Kwon, Yoon Ja;Kang, Heun Soo;Cho, In Ho
    • Journal of the Korean Chemical Society
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    • v.39 no.3
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    • pp.218-223
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    • 1995
  • A simple and efficient synthesis of new kind of Morindaparvin A derivatives (2~8) containing $-N(CH_3)_2,\;-OMe,\;-NH_2,\;-COOH,\;-CHClC(O)NH_2,\;-CHClCH_2OH\;and\;-CHClC(O)CH_3$ was completed with the reported 1,2-dihydroxyanthraquinone derivatives (9, 10).

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A study on Electrical Characteristic and Thermal Shock Property of TSV for 3-Dimensional Packaging (3차원 패키징용 TSV의 열응력에 대한 열적 전기적 특성)

  • Jeong, Il Ho;Kee, Se Ho;Jung, Jae Pil
    • Journal of the Microelectronics and Packaging Society
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    • v.21 no.2
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    • pp.23-29
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    • 2014
  • Less power consumption, lower cost, smaller size and more functionality are the increasing demands for consumer electronic devices. The three dimensional(3-D) TSV packaging technology is the potential solution to meet this requirement because it can supply short vertical interconnects and high input/output(I/O) counts. Cu(Copper) has usually been chosen to fill the TSV because of its high conductivity, low cost and good compatibility with the multilayer interconnects process. However, the CTE mismatch and Cu ion drift under thermal stress can raise reliability issues. This study discribe the thermal stress reliability trend for successful implementation of 3-D packaging.

The effect of PCN substitution on dielectric and piezoelectric properties of PMN-PZT Ceramics (PCN 치환이 PMN-PZT 세라믹스에 유전 및 압전특성에 미치는 영향)

  • Nam, Seung-Hyon;Yoo, Ju-Hyun;Lee, Su-Ho;Jeong, Yeong-Ho;Park, Chang-Yub
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.04b
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    • pp.161-164
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    • 2004
  • In this study, to develop the composition ceramics for the Ultrasonic vibrator, $Pb(Mn_{1/3}Nb_{2/3})O_3Pb(Zr.Ti)O_3$ system ceramics were manufactured as a function of PCN substitution. Its dielectric and piezoelectric characteristics were investigated. With increasing the amount of PCN substitution, electromechanical coupling factor(kp) were increased until 3mol% PCN and that after decreased. mechanical quality factor(Qm) showed the maxinum value at 2mol% PCN. Eletromechanical coupling factor, mechanical quality factor and dielectric constant were showed optimum value at PCN 2mol% as 0.58, 1630 and 1407, respectively for ultrasonic vibrator applications.

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Atmospheric chemistry and characteristics of HCHO, $CH_3CHO$ during intensive measurement for Development of Ozone Forecasting System for Seoul (서울시에 맞는 오존 예보 시스템 개발을 위한 집중 측정 시기의 알데하이드 화합물의 특성 및 대기화학)

  • 홍상범;정용국;이종민;이재훈
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.11a
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    • pp.37-39
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    • 2000
  • 오존에 대한 예보 모델을 연구하는 데는 오존의 생성과 소멸에 관한 광 화학 반응에 대한 이해가 중요한 데 대류권에서 일어나는 알짜 오존 생성(net ozone production)반응은 다음과 같다. (R1) $HO_2$.+NO$\longrightarrow$$NO_2$+OH. (R2) $RO_2$.+NO$\longrightarrow$$NO_2$+RO. (R3) $NO_2$+hu(424< nm) $\longrightarrow$NO+O($^{3}P$) (R4) O($^{3}P$)+$O_2$+M$\longrightarrow$$O_3$+M이때 (R1)과 (R2) 반응에 참여하는 $HO_2$.라디칼 / $RO_2$.라디칼은 주로 대기 중에 존재하는 탄화수소(RH)와 OH.의 반응에 의하여 직접 생성되기도 하고, 이때 생성된 알데하이드(RCHO) 화합물이 OH.과의 반응과 광분해 반응을 통해서 형성된다. 한편, 대도시 지역의 경우 자동차의 배기가스가 알데하이드 화합물의 주요 인위적인 배출원으로 알려져 있다(Viskari et al., 2000, Granby et al., 1997). (중략)

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Cloning and Expression of a cDNA AAPT3 Encoding Aminoalcoholphosphotransferase Isoform from Chinese Cabbage

  • Kim, Kwang-Soo;Park, Jong-Ho;Cho, Sung-Ho
    • Animal cells and systems
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    • v.8 no.2
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    • pp.105-109
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    • 2004
  • Aminoalcoholphosphotransferase catalyzes the synthesis of phosphatidylcholine and phosphatidylethanolamine from diacylglycerol plus a CDP-aminoalcohol such as CDP-choline or CDP-ethanolamine. Previously we suggested the presence of possible isoforms of this enzyme from Chinese cabbage roots and now report the cDNA cloning and expression analysis of AAPT3 encoding a third isoform of aminoalcoholphosphotransferase (AAPT3). AAPT3 contains an open reading frame of 1,176 bp coding for a protein of 392 amino acids. It shares 96 and 95% identity with Chinese cabbage AAPT1 and AAPT2, respectively, at the deduced amino acid level. The results from reverse transcriptase-polymerase chain reaction analysis indicate that expression of AAPT3 is up-regulated by low temperature as well as AAPT1 and AAPT2.

3-Phase High Precision Sinusodial Signal Generator for Performance Measure of Autosyncronizer (자동동기장치 성능평가를 위한 3상 정밀파형발생기 개발)

  • Chung, Tae-Jin;Cha, Young-Ho;Park, Ho-Chul;Chun, Young-Sik;Chung, Chan-Soo
    • Proceedings of the KIEE Conference
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    • 1998.11b
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    • pp.478-480
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    • 1998
  • We develops a simulator to evaluate the performance of the autosyncronizer. The autosyncronizer is used to automatically syncronize magnitude, frequency, and phase of 3 phase signals of generator with respect to those of the utility grid. This autosyncronizer needs to be evaluated its performance to prevent malfunctions. To do this, 3 phase signals of generator and the utility grid are simulated and signals of the generator should be changed by ouput of the autosyncronizer with high precision. In this paper, we uses TMS320C31 to generate high precision sinusoidal 3 phase signals using Table Lookup method. In this process, it is very desirable to control magnitude, frequency, and phase of the signal with high precision and this is achieved by appropriate interpolation method. The resulted signal is well controlled and has low THD and could be used to evaluate the performance of the autosyncronizer.

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A Study on the Morphology of Carbon Nanomaterials prepared by Thermal CVD on the Mechanochemical Treated Catalysts

  • Ryu, Ho-Jin;Yi, Hyung-Kyun;Saito, Fumio;Lee, Byuung-Il;Chang, Ho-Jung
    • Proceedings of the Korean Society Of Semiconductor Equipment Technology
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    • 2002.11a
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    • pp.75-78
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    • 2002
  • CNTs have been grown by the thermal CVD process in which $C_{2}H_{2}$ gas was deposited on the Fe - $Al(OH)_3$ mixture pretreated by mechanochemical treatment with a high energy mixer mill. As the duration time of grinding fer $Fe-(Al(OH)_3$ mixture by the mixer mill increased, amorphous $Al(OH)_3$ and more smaller Fe particles agglomerated into spheres. With unground and ground mixtures of $Fe-Al(OH)_3$, CNTs were grown at $700^{\circ}C$. As a result, CNTs grown on ground mixtures have more uniform diameter and morphology than those of unground mixture. The characterization of $Fe-Al(OH)_3$ mixture and as-grown CNTs were done by XRD, SEM and TEM.

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Development of Construction Method based Automated Estimation System Considering Characteristics of the Domestic Construction Industry (국내 건설 산업에서의 물량산출 특성을 고려한 공법기반 견적자동화 시스템 개발)

  • Jung, Jun-Ho;Lee, Chang-Hee;Kim, Seong-Ah;Chin, Sang-Yoon;Choi, Cheol-Ho
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2010.04a
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    • pp.93-96
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    • 2010
  • 현재 국내외에서 Building Information Modeling을 적용한 여러 분야의 연구가 활발하게 진행되고 있으며, 일부 국외에서는 3D 기반의 견적을 실제 프로젝트에 반영하고 있다. 반면, 국내 건설 프로젝트에서는 여전히 2D 설계도면과 물량산출 프로그램을 이용하여 견적이 이루어지고 있다. 작업의 신속성 및 정확성을 중요시하는 국내 견적 문화에서는 3D 기반의 물량산출 방식 도입을 부정적으로 바라보는 시각이 있으나, 향후 건설 산업의 경쟁력 확보를 위해서 3D 기반 견적작업이 필요하다. 이에 국외에서 상용화된 견적 시스템을 국내 건설 프로젝트에 적용한 결과, 몇 가지 한계점이 있는 것으로 드러나 국내 견적 방식에 적합한 3D기반의 물량산출 프로그램 개발이 절실한 상황이다. 따라서 본 연구에서는 국내 건설 산업에서의 물량 산출 특성을 반영한 공법기반 견적자동화 시스템 개발 및 검증을 통해 국내 3D 기반의 견적 도입을 앞당기고자 한다.

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