• Title/Summary/Keyword: Mixing methods

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Data Fusion Using Image Segmentation in High Spatial Resolution Satellite Imagery

  • Lee, Jong-Yeol
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.283-285
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    • 2003
  • This paper describes a data fusion method for high spatial resolution satellite imagery. The pixels located around an object edge have spectral mixing because of the geometric primitive of pixel. The larger a size of pixel is, the wider an area of spectral mixing is. The intensity of pixels adjacent edges were modified by the spectral characteristics of the pixels located inside of objects. The methods developed in this study were tested using IKONOS Multispectral and Pan data of a part of Jeju-shi in Korea. The test application shows that the spectral information of the pixels adjacent edges were improved well.

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Mixing Characteristics in Supersonic Combustor with a Cavity (Cavity를 이용한 초음속 연소기 내의 혼합특성)

  • Oh Juyoung;Bae Young-Woo;Kim Ki-Su;Jeon Young-Jin;Lee Jae-Woo;Byun Yung-Hwan
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • v.y2005m4
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    • pp.359-363
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    • 2005
  • In SCRamjet engine, combustion occurs in supersonic flow with airbreathing. SCRamjet is characterized by very short combustion time in combustor, so it is very important to be mixing the air and fuel in short duration. Several methods are suggested for mixing enhancement. Among these, cavity is selected to study for enhancement of mixing. The numerical simulation is performed in the case of freestream Mach number of 2.5 and cavity located in front of fuel jet injection. CFD-Fastran, commercial code with three-dimensional Navier-Stokes equation with the Menter SST turbulence model were used. The results are obtained validate experiment results for same condition. Therefore, the numerical results show the mixing enhancement characteristics with a cavity.

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Effects of Mixing Performance and Conditioned Medium on hCTLA4Ig Production in Transgenic Rice Cell Suspension Cultures (형질전환 벼 현탁세포 배양에서 혼합효율과 조정배지가 hCTLA4Ig 생산에 미치는 영향)

  • Choi, Hong-Yeol;Park, Jun-Yong;Nam, Hyung-Jin;Gong, Mi-Kyung;Yoo, Ye-Ri;Kim, Dong-Il
    • KSBB Journal
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    • v.30 no.6
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    • pp.307-312
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    • 2015
  • Transgenic rice cells using RAmy3D promoter can provide high productivity, and the production of recombinant protein is induced by sugar starvation. In this system, productivity was reduced during the scale-up processes. To ensure the influences of shear stress and oxygen transfer rate, working volume and mixing performances were investigated under various agitation speeds and working volumes. In addition, inoculation methods including suspended cells and filtered cells were compared. Working volumes and shaking speeds were 300, 450 mL and 80, 120 rpm, respectively. Hydrodynamic environment of each condition was measured numerically like mixing time and $k_La$. Good mixing performance and high shear stress were measured at high agitation speed and low volume. The highest level of hCTLA4Ig was 30.7 mg/L at 120 rpm, 300 mL. When conditioned medium was used for inoculation, increased cell growth was noticed during the day 0~4 and decreased slower than filtered cells. Compared with filtered cells, the maximum hCTLA4Ig level reached 37.8 mg/L at 120 rpm, 300 mL and lower protease activity level was observed. In conclusion mixing performance is critical factor for productivity and conditioned medium can have a positive effect on damaged cells caused by hydrodynamic shear stress.

The effect of powder A2/powder A3 mixing ratio on color and translucency parameters of dental porcelain

  • Lee, Wan-Sun;Kim, So-Yeon;Kim, Ji-Hwan;Kim, Woong-Chul;Kim, Hae-Young
    • The Journal of Advanced Prosthodontics
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    • v.7 no.5
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    • pp.400-405
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    • 2015
  • PURPOSE. The purpose of this study is to mix dental ceramic powder in varying ratios and evaluate the effect of the mixing ratio on color and translucency. MATERIALS AND METHODS. The ceramic powder of shade A3 of the same product was mixed with the shade A2 of three products: IPS e.max Ceram (Ivoclar Vivadent, Schaan, Liechtenstein), Vintage Halo (SHOFU Inc., Kyoto, Japan), and Ceramco 3 (Ceramco-Dentsply, Burlington, NJ, USA) in the following fixed ratios (0 wt%, 25 wt%, 50 wt%, 75 wt%, and 100 wt%) and then fired. A total of 150 specimen of ceramic fired were manufactured in a regular size (W: 8.5 mm, L: 10.5 mm, and H: 1.5 mm). For color and translucency, $L^*$, $a^*$, and $b^*$ were measured and Two-way analysis of variance (ANOVA) and One-way analysis of variance (ANOVA) were used for data analysis (${\alpha}$=0.05). RESULTS. The higher the mixing ratio was, $L^*$, $a^*$, and $b^*$ of IPS e.max Ceram were all increased, and $L^*$ of Vintage Halo was reduced and $a^*$ and $b^*$ were increased. $L^*$ and $a^*$ of Ceramco3 were reduced and $b^*$ of Ceramco3 was increased. Color difference (${\Delta}E^*ab$) was increased in all three products as the mixing ratio got higher. Increased mixing ratios resulted in decreased translucency parameter (TP) values for IPS e.max Ceram but increased TP values for Vintage Halo and Ceramco3. CONCLUSION. In this limited study, CIE $L^*$, $a^*$, and $b^*$ were influenced by the mixing ratio of the A3 powders and porcelain powder mixtures represented a various color and translucency.

The Numerical Analysis Study about the Air-Fuel Mixing Characteristics by the Change on the 3D Cavity Size (3차원 Cavity 크기 변화에 의한 공기-연료 혼합특성의 수치적 해석 연구)

  • Seo, Hyung-Seok;Jeon, Young-Jin;Byun, Yung-Hwan;Lee, Jae-Woo
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2007.11a
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    • pp.93-98
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    • 2007
  • The air velocity flowing in inner combustion chamber of SCramjet is supersonic and the time of its stay is very short as a few milliseconds. Within this short time, fuel injection, air-fuel mixing, and combustion process should be accomplished. Several methods are suggested for mixing enhancement. Among these, cavity is selected to study for mixing characteristics. The numerical simulation is performed in the case of freestream Mach number of 2.5 and cavity located in front of fuel jet injection. 3 different sized cavities of the same length-height ratio were used in order to recognize the effect about cavity size. Also, the case without cavity was analyzed to find the effect of cavity. Used code compared with the result of experiment under identical conditions and it was verified. Through this comparison and verification, mixing enhancement by cavity size could be confirmed.

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The Study on Application of Aerated Concrete as a Filling Material for Special Use (특수용도 충전재로서 기포콘크리트의 활용성에 관한 연구)

  • 허재원;이종필;김효열;임남기
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2004.05a
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    • pp.45-50
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    • 2004
  • In this study, we processed two procedures of application test of filler for special-purpose utility that are new application methods of aerated concrete and properties test of aerated concrete according to mixing ratio because we investigated the better use of aerated concrete as filler for fireproof safety and we proposed basic data about standardization of mixing of aerated concrete. We measured flow and volume change of aerated concrete. And if its volume doesn't change, we added measuring unit weight and compressive strength. To test application of aerated concrete as filler for fireproof safety, we filled up aerated concrete to fireproof safety according to suitable mixing ratio. Then we measured maximum temperature of inner part of fireproof safety in accordance with the standard test of fireproof. According to the results, aerated concrete as filler for fireproof safety could be possibly used. So when we make aerated concrete, we should consider using an adding agent as well as a foaming agent.

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Characteristic of Fatigue Crack Behavior on the Mixed-Mode in Aluminum Alloy 5083-O

  • Kim, Gun-Ho;Cho, Kyu-Chun;Lee, Ho-Yeon;Won, Young-Jun
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.7
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    • pp.899-906
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    • 2011
  • Generally, load conditions of machine or structure in fatigue destruction is occurred not under single load conditions but under mixed load conditions. However, the experiment under mixing mode is insufficient because of no having test standard to the behavior of crack under mixing mode and variety of test methods, and many tests are required. In this paper measured crack direction path by created figure capture system when a experiment. Also, we studied by comparison the behavior of crack giving the change of stress ratio and inserting beach mark. Through the test under mixing mode, advancing path of crack is indicated that advancing inclined angle ${\Theta}$ (direction of specimen length) has increased depending on the increase of mixed mode impaction. It is indicated that according to the increase of mixed mode loading condition impaction under mixing mode, advancing speed of crack gets slow. Also, we found that inner crack(cross section of specimen) is progressed more rapidly than outer crack based on data through beach mark.

Geochemical Evolution of Mixing Zone with Freshwater and Seawater near the Coast Area during Underground Space Construction (지하공간건설 시 해안인근 담수-해수 혼합대의 지화학적 진화)

  • Kim, Jiyeon;Kim, Byung-Woo;Kwon, Jang-Soon;Koh, Yong-Kwon
    • Journal of Soil and Groundwater Environment
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    • v.20 no.7
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    • pp.90-102
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    • 2015
  • To understand the hyrogeochemical variation of bedrock aquifer during underground space construction, various graphical methods including multiple-component plots and chemical trends were used to estimate the mixing rate between seawater and freshwater and to investigate the evolution of water quality. The water chemistry and mixing rate between fresh and sea waters, which are generally localized in the construction area (MW-7, in land), shows typical characteristics of freshwater that doesn’t affect its validity as seawater intrusion. Especially, the water chemistry of a MW-4 (coastline) was classified as Na-Cl type, Na-HCO3 type, and Ca-Cl type due to the influence of the seawater intrusion. And hydrogeochemical and isotopic data show that local freshwater is subjected to geochemical processes, such as reverse ion-exchange. Throughout the Chadha’s diagrams, four different case histories with the temporal and spatial variation of groundwaters in the study area were proposed, which is recommended to interpret the hydrogeochemical reactions effectively.

Fundamental Characteristics the Concrete According to Mixing Methods and Unit Water Content of Ternary Blended Cement (3성분계 시멘트의 단위수량 및 혼합방식에 따른 콘크리트의 기초특성)

  • Lee, Il-Sun;Hong, Seak-Min;Baek, Dae-Hyun;Kim, ki-hoon;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2009.11a
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    • pp.133-136
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    • 2009
  • This study analyzes the mixing and basic characteristics of concrete according to the unit quantity and mixing method of ternary blended cement and the results of this study can be summarized as follows. In the case of the premixed cement (hereafter referred as POBF) of POBF135, it satisfies the target level of fluidity and air content in which it shows relatively small bleedings even though it represents the latest initial and final setting. Also, although the POBF135 represents small initial strength, it shows an increase in the strength according to the increase in aging. In addition, it shows the lowest temperature in the POBF135. As a result, it can be seen that the POBF135 indicates the most optimal mixing subject to considering the aspect of fluidity, compressive strength, and heat of hydration in general figures.

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Evaluation of Mixing Conditions for the Production of Optimized High Flowing Concrete

  • Kim, Sang-Chel
    • KCI Concrete Journal
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    • v.11 no.3
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    • pp.79-88
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    • 1999
  • Most difficulties of inducing high fluidity on the concrete mixing design with a strength range of 210 to 240kg/$\textrm{cm}^2$ result from the segregation of aggregates due to the shortage of cementitious binders. To solve the problem, this study concentrated on finding the optimized amount of binder material which does not affect the concrete strength and is also economical. Also there were studies on the use of intermediate sized aggregates to avoid the gap-grading between coarse and fine aggregates so that the material segregation in high flowing concrete was and minimalized the fluidity and penetration capacity of the reinforcing bars was enhanced. Throughout the parametric study with respect to water/binder ratio. superplasticizer. replaceable mineral admixture, the size of coarse aggregate and mixing methods, the effect of each constituent on the characteristics of high flowing concrete could be observed. As a result or partially using stone powder or an intermediate class of aggregate (max. diameter 13mm) . it was fund that the fluidity of concrete significantly increased without material segregation and any change of compressive strengths. It was also proved in this study that proper mixing time and speed are significant factors influence the performence of high flowing concrete.

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