• Title/Summary/Keyword: O-D analysis

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Extractives from Pollen (화분의 추출성분)

  • 이상극;김진규;함연호;박재군;배영수
    • Journal of Korea Foresty Energy
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    • v.22 no.1
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    • pp.30-36
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    • 2003
  • 2kg of pollen extracted with EtOH(98%), concentrated, and fractionated with a series of hexane, CH$_2$Cl$_2$ EtOAc and $H_2O$ on a separately funnel. Each fraction was freeze dried to give dark-brown powder and EtOAc soluble portion of the powder was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol as eluents. Spectrometric analysis such as NMR and FAB-MS including TLC were performed to characterize the structures of isolated compounds. Pollen contained a small amount of flavonol derivatives such as quercetin-3-O-$\beta$-D-glucopyranoside and kaempferol-3-O-$\beta$-D-rutinoside in addition to a small amount of flavanonol compound such as aromadendrin-5-methyl ether and acid compound such as.

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Structural and Optical Properties of TiO$_2$ Films Deposited by MOCVD (MOCVD 법에 의해 증착된 TiO$_2$ 박막의 결정구조 및 광학적 특성)

  • 장동훈;강성준;윤영섭
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.6
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    • pp.50-57
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    • 1997
  • TiO$_{2}$ tin films have been grown by MOCVD and their cahracteristics of crystallization and microstructures ahve been invetigated. Envelope mehtods are applied to the analysis of the transmission spectra to obtain the optical constants such as refractive indices and extinction coefficients for the TiO$_{2}$ thin films. The envelope methods are proved to be accurate by simulatin gthe transmission spectra. TiO$_{2}$ thin films start to crystallize at 350.deg.C and then crystallize fully into anatase phase at 400.deg.C or higher temperatures. Activation energies are obtained by plotting the deposition rate with varying the substrate temperature. It is 17.8 kcal/mol for the reaction limited regions. The refractive index and the extinction coefficient of the TiO$_{2}$ thin film at .gamma.=632.8 nm increases from 2.19 to 2.32 and decreases from 0.021 to 0.007, respectively, as the substrate temperature increases from 400 to 600.deg. C.

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A Study on Ways to Improve Benefits of Travel-time in Analyzing the Economic Efficiency (경제성분석시 통행시간절감편익 개선방안에 관한 연구)

  • Lee, Sooil;Lee, Seungjae
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.3D
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    • pp.263-270
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    • 2010
  • This research has reviewed the ways to improve the benefits of shortening of transit hours among the benefit items in analysis of economic efficiency. The existing way of calculating the benefits of shortening the transit hours in analysis of economic efficiency has been using O/D in peak to multiply by 365. This method has a problem of not considering the change of traffic according to the month and the day of the week. To improve such problem, the volume of traffics at 361 regular research branches of the chronological statistics of traffic volume was used to analyze the pattern change of traffic volume per day of the week and per month by t-test and cluster analysis. The results show a difference in traffic volume according to the day of the week and the month. In the research example, a supposed O/D and network were used to apply weight per day of the week and per month to see a slight difference with the existing method of calculating benefits of shortening the transit hours. This signifies the necessity to study about the weight to consider the change pattern of traffic volume.

Synthesis of $Eu^{3+}$ activated $LnAlO_{3}$(Ln=Y and Gd) Phosphors by combusition method (연소법에 의한 $LnAlO_{3}$(Ln=Y and Gd):$Eu^{(3+)}$ 형광체의 합성)

  • Khatkar, S.P.;Taxak, V.B.;Han, Sang-Do;Kim, Byeong-Kwon;Jung, Young-Ho;Park, Jo-Yong;Liang, Y.;Myung, Kwang-Shik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.116-119
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    • 2002
  • A different route to the synthesis of $Eu^{3+}$ - activated matrices such as $YAlO_{3}$ and $GdAlO_{3}$ and luminiscent properties of these compounds, were studied. The new route (Combustion method) consist of the redox reactions between the respective metal nitrates and urea in a preheated furnace at ${500^{\circ}C}$. The Phosphor thus obtained were then heated at ${1000^{\circ}C}$ for 2-3 hours to get better luminiscent properties. The incorporation of $Eu^{3+}$ activator in these phosphors were checked by luminiscence investigations. Scanning electron microscopy (SEM) studies were carried out to understand surface morphological features and the particle size. X-ray energy dispersive analysis (EDAX) was also performed for the qualitative analysis of the phosphors.

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Quantitative Analysis of Flavonoid Glycosides in Sophora japonica and Sophora flavescens by HPLC-DAD

  • Kim, Soo Sung;Park, SeonJu;Kim, Nanyoung;Kim, Seung Hyun
    • Natural Product Sciences
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    • v.27 no.4
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    • pp.284-292
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    • 2021
  • Recently, a phytoestrogenic functional food has been developed using the fruits of Sophora japonica. Phytochemical investigation of fruits of S. japonica led to the isolation of eight flavonoid glycosides using various chromatographic techniques. The isolated compounds were identified as genistin (1), sophoricoside (2), genistein 7,4'-di-O-β-D-glucopyransoide (3), sophorabioside (4), genistein-7-O-β-D-glucopyranoside-4'-O-[(α-L-rhamnopyranosyl)-(1→2)-β-D-glucopyranoside] (5), sophoraflavonoloside (6), nicotiflorin (7) and kaempferol-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranosyl-(1→3)-β-D-glucopyranoside (8), respectively, by comparison of their spectroscopic data with those reported in the literature. In addition, a new HPLC-DAD method for simultaneous determination of the isolated compounds was developed to quantitate the contents of flavonoids in S. japonica and S. flavescens. The method was validated in terms of limit of detection, limit of quantitation, specificity, linearity, precision and accuracy. The validated method was successfully applied to determine eight flavonoids in two Sophora species. The contents of eight flavonoids varied according to the parts and species. Particularly, it was found that only the fruits of S. japonica contained sophoricoside, a phytoestrogenic isoflavone.

Component Analysis of Suaeda asparagoides Extracts (나문재 추출물의 성분 분석)

  • Yang, Hee-Jung;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.34 no.3
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    • pp.157-165
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    • 2008
  • In the previous study, the anti-oxidant activity of oxtract/fraction of Sueada aspparagoides(SA) and the stability test for the cream containing SA extract were investigated respectively[1,2]. In this study, the components of SA extract were analyzed by TLC, HPLC, and LC/ESI-MS/MS, $^1H$-NMR. TLC chromatogram of ethyl acetate fraction of SA extract revealed 5 bands $(SA1{\sim}SA5)$. HPLC chromatogram of aglycone fractions obtained from deglycoylation reaction of ethyl acetate fraction showed 2 bands (SAA 2 and SAA 1), which were identified as quercetin (composition ratio, 16.88%) and kaempferol (83.12%) in the order of elution time. Among 5 bands of TLC chromatogram, 4 bands $(SA2{\sim}SA5)$ also were Identified as kaempferol-3-O-glucoside (SA 2), quercetin-3-O-glucoside (SA3), kaempferol-3-O-rutinoside (SA 4), quercetin-3-O-rutinoside (SA 5) by LC/ESI-MS/MSMS/MS. respectively. The spectrum generated for SAA 1 by LC/ESI-MS/MS in the negative ion mode also gave the ion corresponding to the deprotonated aglycone $[M-H]^-$ (285m/z), the $^1H$-NMR spectrum contained signals [${\delta}$ 6.19 (1H, d, J=1.8Hz, H-6), ${\delta}$ 6.44 (1H, d, J=1.8Hz, H-8), ${\delta}$ 6.92 (2H, d, J=9.0Hz, H-3', 5'), ${\delta}$ 8.04 (2H, d, J=9.0Hz, H-2', 6', thus SAA 1 was identified as kaempferol. SAA 2 yielded the deprotonated agycone ion $[M-H]^-$ (301m/z), $^1H$-NMR spectrum showed signals [${\delta}$ 6.20 (1H, d, J=2.0Hz, H-6), ${\delta}$ 6.42 (1H, d, J=2.0Hz, H-8), ${\delta}$ 6.90 (1H, d, J=8.6Hz, H-5'), ${\delta}$ 7.55 (1H, dd, J=8.6, 2.2Hz, H-6'), ${\delta}$ 7.69 (1H, d, J=2.2Hz, H-2', thus SAA 2 was Identified as quercetin. In conclusion, with the anti-oxidant activity and the stability test reported previously, component analysis of SA extracts could be applicable to new cosmeceuticals.

Microstructural analysis and characterization of 1-D ZnO nanorods grown on various substrates (다양한 기판위에 성장한 1차원 ZnO 나노막대의 특성평가 및 미세구조 분석)

  • Kong, Bo-Hyun;Kim, Dong-Chan;Cho, Hyung-Koun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.116-117
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    • 2006
  • I-D ZnO nanostructures were fabricated by thermal evaporation method on Si(100), GaN and $Al_2O_3$ substrates without a catalyst at the reaction temperature of $700^{\circ}C$. Only pure Zn powder was used as a source material and Ar was used as a carrier gas. The shape and growth direction of synthesized ZnO nanostructures is determined by the crystal structure and the lattice mismatch between ZnO and substrates. The ZnO nanostructure on Si substrate were inclined regardless of their substrate orientation. The origin of ZnO/Si interface is highly lattice-mismatched and the surface of the Si substrate inevitably has the $SiO_2$ layer. The ZnO nanostructure on the $Al_2O_3$ substrate was synthesized into the rod shape and grown into particular direction. For the GaN substrate, however, ZnO nanostructure with the honeycomb-like shape was vertically grown, owing to the similar lattice parameter with GaN substrate.

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Hydrogeochemical Characteristics of Groundwater on Well Depth Variation in the Heunghae Area, Korea (심도 변화에 따른 흥해지역 지하수의 수리 지화학적 특성)

  • Yun Uk;Cho Byong-Wook
    • The Journal of Engineering Geology
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    • v.15 no.4 s.42
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    • pp.391-405
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    • 2005
  • Chemical and isotopic analysis for stream water, shallow groundwater, intermediate groundwater and deep groundwater was carried out to grasp hydrogeochemical characteristics of groundwater in the Heunghae area, Pohang city. Water type of stream water and shallow groundwaters is typified as Ca-Cl type, intermediate groundwater is $Na-HCO_3$, and deep groundwater is prominent in Wa-Cl type. $HCO_3^-\;and\;SiO_2$ in shallow groundwater are originated from weathering of silicate minerals, whereas those of deep groundwaters are resulted from weathering of carbonate minerals. Ca and Mg ions in both shallow and deep groundwaters are resulted from weathering of calcite and dolomite. $SO_4^{2-}$ in shallow groundwater is originated mainly from pyrite oxidation. As well depth increases, pH and TDS increase, but Eh and DO decrease. Alkali metal contents(K, Na, Li) increases as well depth increases, but alkali earth metal(Mg, Ca) and hi concentrations increase as well depth decreases. Anions, halogen elements(F, Cl, Br), and $HCO_3$ contents increase as well depth increases. The average stable isotope value of the groundwater of each depth is as follows; deep groundwater: ${\delta}^{18}O=-10.1\%o,\;{\delta}D=-65.8\%_{\circ}$, intermediate groundwater: ${\delta}^{18}O=-8.9\%_{\circ},\;{\delta}D=-59.6\%_{\circ}$, shallow groungwater : ${\delta}^{18}O=-8.0\%_{\circ},\;{\delta}D=-53.6\%_{\circ}$, surface water : ${\delta}^{18}O=-7.9\%_{\circ},\;{\delta}D=-53.3\%_{\circ}$ respectively.

Feasibility Study on Introduction of Piggy-back System by Applying Transport Database

  • Lee, Yong-Jae;Lee, Chulung;Kim, Yong-Hoon;Han, Seong-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.1
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    • pp.157-166
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    • 2022
  • In this study, The goal is to analyze the feasibility of introducing a Piggyback system that can reduce the time and cost incurred by transshipment work and improve the transportation speed when transporting complex cargo by rail. To this end, the feasibility analysis methodology is reviewed through domestic and international literature review. In order to quantitatively derive the feasibility analysis values, a transportation database was applied to develop a freight transport simulation model and a freight demand prediction model for major freight transport O-D routes with a transportation distance of 200 km or more. As a result of analyzing economic feasibility by setting the analysis period to 15 years on the premise that the Piggyback System will be introduced on major cargo transport O-D routes in 2025, the NPV value was positive and the B/C value was 1.18, indicating that the Piggyback system was economical. The proposed research method can be meaningful data for establishing transportation policies that can improve the competitiveness of railroad transportation.

Eddy current loss calculation of flux shield in the large turbo generator using axi-periodic analysis (Axi-periodic Analysis를 이용한 대형 터보 발전기 단부 Flux Shield의 Eddy Current Loss 산정)

  • Kwon, Soon-O;Lee, Jung-Jong;Hong, Jung-Pyo;Nam, Hyuk
    • Proceedings of the KIEE Conference
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    • 2005.07b
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    • pp.987-989
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    • 2005
  • Axi-periodic analysis using magnetic vector potential is formulated in time harmonic field and applied to the field analysis for the end region of large turbo generator in this paper. By using axi-periodic analysis, the effect of flux shield, one of the structure placed in the end region of large turbo generator to prevent stator end from thermal damage, is studied, and eddy current loss in the flux shield is estimated for operation conditions. 3D FEA is used for the verification of presented analysis method. Because 3D flux distribution can be calculated with 2D modeling, magnetic field showing 3D distribution can be effectively calculated by axi-periodic analysis comparing with 3D FEA.

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