• Title/Summary/Keyword: Mixing Pattern

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Hydrogen Evolution by Mixed Culture of Clostridia with Rhodopseudornonas sphaeroides (Rhodopseudomonas sphaeroides와 Clostridia의 혼합)

  • Yi, Hye-Joo;Bae, Moo
    • Microbiology and Biotechnology Letters
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    • v.20 no.4
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    • pp.430-436
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    • 1992
  • Hydrogen evolution by mixed fermentation of Clostn"dium butyn"cum and photosynthetic bacteria which were capable of consuming clostridial metabolites and evolving hydrogen was investigated. Acetate and butyrate formed from anaerobic clostridial fermentation were efficiently utilized by Rhodopseudomonas sPhaeroides K-7. For complete bioconversion of clostridial metabolites such as acetate and butyrate into hydrogen, mixed culture of both anaerobic organisms forming molecular hydrogen was performed. By the mixed culture, the yield of hydrogen production increased by 20 to 75% and the levels of clostridial metabolites such as acetate, butyrate decreased in the fermentation broth. Influence of cell mixing ratio. mixing time and inoculum level on hydrogen evolution by mixed culture were examined. And then cometabolic pattern compared with in pure culture was observed as time course.

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Effect of Heat Flux on the Melting Efficiency and Penetration Shape in TIG Welding (TIG 용접에서 열유속이 용융효율과 용입형상에 미치는 영향)

  • Oh, Dong-Soo;Cho, Sang-Myung
    • Journal of Welding and Joining
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    • v.27 no.2
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    • pp.44-50
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    • 2009
  • The characteristics of arc pressure, current density and heat flux distribution are important factors in understanding physical arc phenomena, which will have a marked effect on the penetration, size and shape of a weld in TIG welding. The purpose of this study is to find out the effect of the heat flux on the melting efficiency and penetration shape in TIG welding using the results of the previous investigators. The conclusions obtained permit to draw a proper method which derived the heat flux distributions by arc pressure distribution measurements, but previous researchers calculated heat flux and current distribution with the heat intensity measurements by the calorimetry. Heat flux of Ar gas arc was concentrated at the central part and distributed low from the arc axis to the radial direction, that of He mixing arc was lower than that of Ar gas, and it was wide distributed to radial direction. That showed a similar characteristic with the Nestor's by calorimetry calculated values. Throughout heat flux drawn in this study was discussed melting efficiency and penetration shape on Ar gas and He mixing gas arc.

Study for Design and Performance Characteristics of Small Bipropellant Thruster using $H_2O_2$/Kerosene (과산화수소/케로신 소형 이원추진제 추력기의 설계 및 성능특성에 관한 연구)

  • Kim, Jung-Hoon;Lee, Jae-Won;Jeon, Young-Jin;Chae, Byoung-Chan;Jeon, Jun-Su;Kim, Yoo;Kim, Sun-Jin
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2009.05a
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    • pp.41-45
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    • 2009
  • The small-sized bi-propellant thruster using a high concentrated hydrogen peroxide and kerosene as the oxidizer and fuel was designed and fabricated in this study. The water cold-flow test was performed to verify the performance characteristics of the injector. The mixing head assembly used in this model thruster was designed as a structure to combine igniter, injectors and film cooling, which are capable of regulating each mass flowrate. This maximize the experimental verification and efficiency of the design optimization. Finally, the mass flowrate and spray pattern of injector were evaluated by the hydraulic test. Therefore, the design validity of the mixing head was verified.

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Traffic Extraction and Verification for Attack Detection Experimentation (공격탐지 실험을 위한 네트워크 트래픽 추출 및 검증)

  • Park, In-Sung;Lee, Eun-Young;Oh, Hyung-Geun;Lee, Do-Hoon
    • Convergence Security Journal
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    • v.6 no.4
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    • pp.49-57
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    • 2006
  • Firewall to block a network access of unauthorized IP system and IDS (Intrusion Detection System) to detect malicious code pattern to be known consisted the main current of the information security system at the past. But, with rapid growth the diffusion speed and damage of malicious code like the worm, study of the unknown attack traffic is processed actively. One of such method is detection technique using traffic statistics information on the network viewpoint not to be an individual system. But, it is very difficult but to reserve traffic raw data or statistics information. Therefore, we present extraction technique of a network traffic Raw data and a statistics information like the time series. Also, We confirm the validity of a mixing traffic and show the evidence which is suitable to the experiment.

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Experimental studies on mass transport in groundwater through fracture network using artificial fracture model

  • Tsuchihara Takeo;Yoshimura Masahito;Ishida Satoshi;Imaizumi Masayuki;Ohonishi Ryouichi
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.676-683
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    • 2003
  • A laboratory experiment using artificial fracture rocks was used to understand the 3-dimensional dispersion of a tracer and the mixing process in a fractured network. In this experiment, 12cm polystyrene foam cubes with two electrodes for monitoring electric conductivity (EC) were used as artificial fractured rocks. Distilled water with 0.5mS/m was used as a tracer in water with 35mS/m and the difference of EC between the tracer and the water was monitored by a multipoint simultaneous measurement system of electrical resistance. The results showed that even if the fracture arrangement pattern was not straight in the direction of the flow, the tracer did not diffuse along individual fractures and an oval tracer plume, which was the distribution of tracer concentrations, tended to be form in the direction of the flow. The vertical cross section of the tracer distribution showed small diffusivity in the vertical direction. The calculated total tracer volume passing through each measurement point in the horizontal cross section showed while that the solute passed through measurement points near the direction of hydraulic gradient and in other directions, the passed tracer volumes were small. Using Peclet number as a criterion, it was found that the mass distribution at the fracture intersection was controlled in the stage of transition between the complete mixing model and the streamline routing model.

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The Patterning of Polyimide Thin Films for the Additive $CF_4$ gas ($CF_4$ 첨가에 따른 polyimide 박막의 패터닝 연구)

  • Kang, Pil-Seung;Kim, Chang-Il;Kim, Sang-Gi
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.209-212
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    • 2001
  • Polyimide(PI) films have been considered as the interlayer dielectric materials due to low dielectric constant, low water absorption, high gap-fill and planarization capability. The PI mm Was etched with using inductively coupled plasma (ICP). The etching characteristics such as etch rate and selectivity were evaluated to gas mixing ratio. High etch rate was $8300{\AA}/min$ and vertical profile was approximately acquired $90^{\circ}$ at $CF_{4}/(CF_{4}+O_{2})$ of 0.2. The selectivies of polyimide to PR and $SiO_{2}$ were 1.2, 5.9, respectively. The etching profiles of PI films with an aluminum pattern were measured by a scanning electron microscope (SEM). The chemical states on the PI film surface were investigated by x-ray photoelectron spectroscopy (XPS). Radical densities of oxygen and fluorine in different gas mixing ratio of $O_{2}/CF_{4}$ were investigated by optical emission spectrometer (OES).

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A Study of The Stripe Patterns on The Fabric Design Since 2000 (년대 2000 이후 섬유디자인에 나타난 스트라이프 패턴 연구)

  • Han, Jung-Im
    • Journal of Fashion Business
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    • v.15 no.2
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    • pp.160-173
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    • 2011
  • Stripe has been one of the all-time favorite fabric patterns so far and the usages have been widely applied of nearly everything ranging from everyday dress to interior fabrics. As the times change, patterns of this simple geometrical design have gradually become varied. Many effects of stripe patterns have allowed the patterns to be used in fabrics for fashion design and the patterns are considered fit for expressing individual characteristics. By studying theoretical background on categories of stripe patterns and the characteristics as a design and by researching the trends and properties exhibited in the modern fabric design, this paper will seek the potential of stripe patterns for design of a modern sense and the directions to express the patterns as a value-added design. This research was conducted through literature, books published at home and abroad, research papers and photographs on stripe patterns. Domestic magazines, web research, and photographs published since 2000 were studied for an analysis of the trends and characteristics of stripe patterns displayed in the modern fabric design. As the results, this research will explain the tendencies of stripe patterns on the modern fabric designs divided into several ways: simple and restrained modernity, active and sporty property, mannishness putting practicality forward-emerging as the status of women rises, and femininity emphasizing elegant women. The characteristics of the Plastic are categorized simplicity, rhythmicality, and Mixing of patterns.

Optimization of Sweet Rice Muffin Processing Prepared with Oak Mushroom (Lentinus edodes) Powder (표고버섯 첨가 찹쌀머핀의 최적화 및 품질특성)

  • Kim, Bo-Ram;Joo, Na-Mi
    • Journal of the Korean Society of Food Culture
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    • v.27 no.2
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    • pp.202-210
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    • 2012
  • The purpose of this study was to bake sweet rice muffins with oak mushroom ($Lentinus$ $edodes$) powder. The process included substituting sweet rice flour for cake flour and adding oak mushroom powder. This study determined the optimal mixing conditions of oak mushroom muffins by adjusting the amounts of oak mushroom powder, whole eggs, and soybean oil. The mixing conditions for the oak mushroom muffins included 3 categories: oak mushroom powder (X1), whole eggs (X2), and soybean oil (X3) by Central Composite Design (CCD) which was optimized by Response Surface Methodology (RSM). Oak mushroom muffin formulation was optimized using rheology. Yellowness (p<0.001) and redness (p<0.05) displayed a linear model pattern, whereas lightness (p<0.05) was represented by a quadratic model. Among the sensory properties, variables that appeared to show significant values such as appearance (p<0.5), texture (p<0.5), and overall quality (p<0.5) were used to identify optimums. The result of mechanical properties showed significant values in gumminess (p<0.5) and chewiness (p<0.5). The numerical and graphical methods used in this study determined that the optimum formulation for oak mushroom powder sweet rice muffins was 8.75 g of oak mushroom powder, 235.95 g of whole eggs, and 19.93 g of soybean oil.

Variations of Physical Oceanographic Environment Caused by Opening and Closing the Floodgate in Nakdong Estuary (수문개폐에 따른 낙동강 하구둑 하류부의 해양물리환경변화)

  • Kim Ki-Cheol;Yang Han-Soeb;Kim Cha-Kyum;Moon Chang-Ho;Jang Sung-Tae
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.2 no.2
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    • pp.49-59
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    • 1999
  • Nakdong Estuary is complex water system, where sea water and fresh water meet each other. After construction of Nakdong River Barrier, the flow pattern and mixing processes have been changed. Variations of physical oceanographic environment in Nakdong Estuary due to opening and closing the floodgate of Nakdong River Barrier are analysed focusing the movement of outflows from the barrier. Surveys and analysis were made for the three cases. 1. Ordinary times (opening and closing the gate by the tidal period) 2. A period of flood time (opening the gate) 3. A period of water shortage (closing the gate).

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Design and Cold Flow test of a Multi-injector Engine using Hydrogen Peroxide/Kerosene (과산화수소 케로신을 추진제로하는 다중 인젝터 설계 및 수류실험)

  • Kim, Ki-Woo;Jeon, Jun-Su;Park, Jin-Ho;Ko, Young-Sung;Kim, Yoo;Kim, Sun-Jin
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.05a
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    • pp.95-98
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    • 2010
  • A multi-injector rocket engine using high concentrated hydrogen peroxide and kerosene as the oxidizer and fuel was designed and fabricated. Six coaxial swirl injectors were mounted on the mixing head and flow analysis in the manifold was performed to minimize stagnation and recirculation zones. Finally, uniformity of mass flow rate and spray pattern was evaluated by cold flow tests and the mixing head design process was successfully verified the results.

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