• Title/Summary/Keyword: surface acts

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Estimation of Water Storage in Small Agricultural Reservoir Using Sentinel-2 Satellite Imagery (Sentinel-2 위성영상을 활용한 농업용 저수지 가용수량 추정)

  • Lee, Hee-Jin;Nam, Won-Ho;Yoon, Dong-Hyun;Jang, Min-Won;Hong, Eun-Mi;Kim, Taegon;Kim, Dae-Eui
    • Journal of The Korean Society of Agricultural Engineers
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    • v.62 no.6
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    • pp.1-9
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    • 2020
  • Reservoir storage and water level information is essential for accurate drought monitoring and prediction. In particular, the agricultural drought has increased the risk of agricultural water shortages due to regional bias in reservoirs and water supply facilities, which are major water supply facilities for agricultural water. Therefore, it is important to evaluate the available water capacity of the reservoir, and it is necessary to determine the water surface area and water capacity. Remote sensing provides images of temporal water storage and level variations, and a combination of both measurement techniques can indicate a change in water volume. In areas of ungauged water volume, satellite remote sensing image acts as a powerful tool to measure changes in surface water level. The purpose of this study is to estimate of reservoir storage and level variations using satellite remote sensing image combined with hydrological statistical data and the Normalized Difference Water Index (NDWI). Water surface areas were estimated using the Sentinel-2 satellite images in Seosan, Chungcheongnam-do from 2016 to 2018. The remote sensing-based reservoir storage estimation algorithm from this study is general and transferable to applications for lakes and reservoirs. The data set can be used for improving the representation of water resources management for incorporating lakes into weather forecasting models and climate models, and hydrologic processes.

Partial Purification and Characterization of a Glycoprotein Factor from Fresh Ginseng

  • Kong, Yun-Cheung;Fong, Wing-Ping;Song, Myung-Eun;Ng, Kam-Hung;Ho, Dan-Dan;Ng, Ping-Chung
    • Proceedings of the Ginseng society Conference
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    • 1990.06a
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    • pp.79-85
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    • 1990
  • The aqueous extract of fresh ginseng (Panax ginseng C.A. Meyer) contains a macromolecular fraction that showed mitogenic and comitogenic activities in human peripheral blood Iymphocytes. Purification of the crude extract by size (ultrafiltration, Sephadex G-200) and charge (DEAE-cellulose. DEAE-Sepharose) yielded a semi-purified fraction (DS-3). This fraction contains at least three subgroups of anionic macromolecules with apparent molecular weight greater than 600 kilodaltons. It is a glycoprotein with a large amount of glucuronic acid. It acts as a mitogen in both T and B cells of human peripheral blood lymphocytes. It could also potentiate the mitogenic action of Concanavalin A in Iymphocyte T cells. Such potentiation is not due to increased binding of Concanavalin A to the cell surface. Its mitogenic and co-mitogenic effects do depend on the presence of extracellular Ca2+.

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Study on the Dissolution Behavior of Liquide $CO_2$ Hydrate Injected at the Intermediate Depth of the Ocean (중층심해에 분사된 액체 이산화탄소 하이드레이트 용해에 대한 연구)

  • Kim, Nam-Jin;Park, Sung-Seek;Seo, Hyan-Min
    • New & Renewable Energy
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    • v.4 no.2
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    • pp.12-20
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    • 2008
  • Calculations for the dissolution behavior of liquid CO2 droplets released in the East Sea and the Clipperton Clarion from a moving ship and a fixed pipeline have been carried out in order to estimate the CO2 dissolution characteristics in the ocean. The results show that the injection of liquid CO2 from a moving ship in a high temperature point is an effective method for dissolution. Also, it is noted that the ultimate plume generated from CO2 bubbles repeatsand shrinking due to the peeling from a fixed pipeline, and the presence of hydrate layer on a liquid CO2 droplet acts as a resistant layer in dissolving liquid CO2.

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Syntheses, Spectral, Surface Morphological and Gamma Ray Irradiation Studies of Some Oxomolybdenum(V) and Dioxomolybdenum(VI) Complexes of an Azo Dye Derived from 4-aminoantipyrine

  • Nair, M.L. Harikumaran;Appukuttan, Anju.S.
    • Journal of the Korean Chemical Society
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    • v.56 no.2
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    • pp.217-227
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    • 2012
  • Syntheses of some novel oxomolybdenum(V) and dioxomolybdenum(VI) complexes with an azo dye methoxyphenolazoantipyrine (HL) derived from 4-aminoantipyrine and 2-methoxyphenol are reported. The complexes have been characterized by elemental analyses, molar conductance, magnetic susceptibility data, IR, UV-Vis, $^1H$ NMR, EPR and FAB mass spectral studies. The physicochemical studies and spectral data indicate that HL acts as a bidentate chelating ligand. The complexes have the general formulae [$MoO(HL)XCl_2$] and [$MoO_2(HL)XCl$],where X=Cl, NCS or $NO_3$. All the complexes are found to have distorted octahedral geometry. Structural and morphological characterization of the complexes [$MoO(HL)Cl_3$](1) and [$MoO_2(HL)Cl_2$](4) before and after gamma ray irradiation,was performed by X-ray diffraction and scanning electron microscopy( SEM).The ligand and the complexes were screened for their possible antimicrobial activities.

The Effect of Lignin Compound on Dispersibility of Concrete (Lignin 화합물의 Concrete 분산성에 대한 연구)

  • 문정연;한기성
    • Journal of the Korean Ceramic Society
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    • v.13 no.3
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    • pp.37-42
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    • 1976
  • Although the water mixed into the concrete plays the role of hydration and acquiring the necessary workability, the more portion of water acts to obtain the substantial workability rather than to complete the hydration. However, the excess amount of water causes the poor quality of concrete, therefore it is useful to add the minimum amount of water as required as to acquire the proper workability. There have been the considerable numbers of investigations in which the dispersion phenomena of strong eletrolytic high polymer compounds such as lignosulfate and some of surface activation agents were studied to utilize as the dispersion agent of concrete. In the present study, Na-lignate, dispersion properties of which has not been studied yet, were investigated with the purpose of utilizing as a dispersion agent of concrete. The microscopic observations showed a great improvement in the dispersion of cement particles, also the fluidity and compressive strength of concrete were remarkably increased with the addition of Na-lignate: The addition of Na-lignate by 0.02% showed the increase of 1.76 times and 1.27 times of slump value and flow value respectively, and the compressive strength was increased by 1.07 times.

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Study on the Dissolution Behavior of Liquide $CO_2$ Hydrate Injected at the Intermediate Depth of the Ocean (중층심해에 분사된 액체 이산화탄소 하이드레이트 용해에 대한 연구)

  • Kim, Nam-Jin;Seo, Hyang-Min;Park, Sung-Seek
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.597-601
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    • 2008
  • Calculations for the dissolution behavior of liquid $CO_2$ droplets released in the East Sea and the Clipperton Clarion from a moving ship and a fixed pipeline have been carried out in order to estimate the $CO_2$ dissolution characteristics in the ocean. The results show that the injection of liquid $CO_2$ from a moving ship in a high temperature point is an effective method for dissolution. Also, it is noted that the ultimate plume generated from $CO_2$ bubbles repeatsand shrinking due to the peeling from a fixed pipeline, and the presence of hydrate layer on a liquid $CO_2$ droplet acts as a resistant layer in dissolving liquid $CO_2$.

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Prediction of Anode Temperatures of Free Burning Arcs Using a Simplified Unified Model

  • Jeon, Hong-Pil;Lee, Jong-Cheol
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.565-565
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    • 2013
  • Free burning arcs where the work piece acts as an anode are frequently used for a number of applications. Our investigation is exclusively concerned with a simplified unified model of arcs and anode under steady state conditions at atmospheric pressure. The model is used to make predictions of arc and anode temperatures and arc voltage for a 200 A arc in argon. The computed temperatures along the axis between the cathode tip and the anode surface compare well the measured data. This knowledge of free burning arcfeatures can play a role in developing the atmospheric plasma systems, however, further investigation should include the modelling of Cu evaporation from anode and non-LTE situation near electrodes for more realistic calculations.

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Study on Optimization of Dissimilar Friction Welding of Nuclear Power Plant Materials and Its Real Time AE Evaluation (원자력 발전소용 이종재 마찰용접의 최적화와 AE에 의한 실시간 평가에 관한 연구)

  • 권상우;오세규;유인종;황성필;공유식
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2000.10a
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    • pp.42-46
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    • 2000
  • In this paper, joints of Cu-1Cr-0.1Zr alloy to STS316L were performed by friction welding method. Cu-1Cr-0.1Zr alloy is attractive candidate as nuclear power plant material and exibit the best combination of high sts good electrical and thermal conductivity of any copper alloy examined. The stainless steel is a structural material who alloy acts as a heat sink material for the surface heat flux in the first wall. So, in this paper, not only the develop optimizing of friction welding with more reliability and more applicabililty but also the development of in-process rear quility(such as strength and toughness) evaluation technique by acoustic emission for friction welding of such nuclear component of Cu-1Cr-0.1Zr alloy to STS316L steel were performed.

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A Study on the Transfer of Molten Drop in MIG Welding (MIG 용접에서 용융 드롭의 이행에 관한 연구)

  • 박기영;이세헌;엄기원
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.538-541
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    • 1996
  • The flow of the molten drop in the GMAW was observed to explain the mechanism of its formation and break-up process. Fluid flew analysis was made with the assumption that the electrode wire acts like fluid, and it is shown how the convection of the drop inside affects its flow, from the formation to the break-up of the drop. In later part, the process of the spray mode development at high current is shown, as well as the one of the globular mode, by the fluid flow analysis.

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Plasmin Inhibitory Activity of Medicinal Plants (수종 식물의 Plasmin 저해 활성 검색)

  • Park, Mi-Hyoun;Jung, Hyun-Ju;Bae, Ki-Hwan;Kim, Young-Ho
    • Korean Journal of Pharmacognosy
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    • v.29 no.3
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    • pp.149-154
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    • 1998
  • Binding of urokinase-type plasminogen activator to its cellular receptor accelerate production of plasmin from plasminogen on the cell surface. Plasmin can digest extracellular matrix components and basement membranes through activating certain proMMPs, which is related to the invasiveness to the cells. Plasmin also acts the regulation of blood coagulation and relates closely to cardiovascular diseases such as stroke and coronary occlusion. Therefore, its inhibitors may be useful as antimetastatic agents and to the treatment of cardiovascular diseases. To search for plasmin inhibitors from plant resources, we screened plasmin inhibitory activities with 76 methanol extract of plant species. Among them, three plant samples showed strong inhibitory activities (>70%) and thirteen plant samples showed more than 50% inhibitory activities of plasmin. Their inhibitory activities were not directly related with uPA inhibitory activites and cell viability.

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