• Title/Summary/Keyword: formation processes

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A study on the variations of a grouping genetic algorithm for cell formation (셀 구성을 위한 그룹유전자 알고리듬의 변형들에 대한 연구)

  • 이종윤;박양병
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2003.11a
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    • pp.259-262
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    • 2003
  • Group technology(GT) is a manufacturing philosophy which identifies and exploits the similarity of parts and processes in design and manufacturing. A specific application of GT is cellular manufacturing. the first step in the preliminary stage of cellular manufacturing system design is cell formation, generally known as a machine-part cell formation(MPCF). This paper presents and tests a grouping gentic algorithm(GGA) for solving the MPCF problem and uses the measurements of e(ficacy. GGA's replacement heuristic used similarity coefficients is presented.

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Dual Nano-Electrospray and Mixing in the Taylor Cone

  • Radionova, Anna;Greenwood, David R.;Willmott, Geoff R.;Derrick, Peter J.
    • Mass Spectrometry Letters
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    • v.7 no.1
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    • pp.21-25
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    • 2016
  • Dual-channel nano-electrospray has recently become an ionization technique of great promise especially in biological mass spectrometry. This unique approach takes advantage of the mixing processes that occurs during electrospray. Understanding in more detail the fundamental principles influencing spray formation further study of the origins of the mixing processes: (1) in a Taylor cone region, (2) in charged droplets or (3) in both environments. The dual-channel emitters were made from borosilicate theta-shape glass tubes (O.D. 1.2 mm) and had a tip diameters of less than 4 μm. Electrical contact was achived by deposition of a thin film of an appropriate metal onto the surface of the emitter. The experimental investigation of the Taylor cone formation in a dual-channel electrospray emitter has been carried out by injection of polystyrene beads (diameter 3 μm) at very low concentrations into one of the channels of the non-tapered theta-glass tubes. High-speed camera experiments were set up to visualize the mixing processes in Taylor cone regions for dual-channel emitters. Mass spectra from dual nano-electrospray are presented.

Investigation on the Practical Use of Gas Hydrate in Gas Industry (가스하이드레이트 산업시스템 실용화 현황 및 동향 분석)

  • Kwon Ok-Bae;Sin Chang-Hun;Park Seung-Su;Han Jeong-Min;Lee Jeong-Hwan
    • New & Renewable Energy
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    • v.2 no.2 s.6
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    • pp.102-107
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    • 2006
  • In Japan, research and development were undertaken on gas hydrate-side industrial processes associated with power generation system connections that may particularly be necessary to develop gas hydrated technology-based industrial systems. In so doing, data and engineering technologies useful n formulating guidelines on design of practical process were accumulated. In addition, basic research into theoretical evidence were carried out to promote and support the development of technological elements for those processes. In basic research designed to promote and support the research and development of elemental technologies, microanalyses were conducted to understand the decomposition mechanism of mixed gas hydrate. Moreover, measurement technologies that can be applied in industrial processes, such as numerical analyses and concentration measurement, were examined. Japan has developed a highly efficient gas hydrate formation process using micro-bubbles with a tubular reactor. Higher formation rate over conventional systems has been obtained by the process. As mentioned above, the technical problems were clarified and the economics were studied from a view point of the NGH technology in this study. The results can be applied for utilization and must contribute to popularization of gas hydrate production.

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Fertilization Processes in Porcine Oocytes Following Intracytoplasmic Injection of Porcine and Mouse Spermatozoa

  • Lee, Youn-Jeung;Kim, Bong-Ki;Park, Chang-Sik;Kim, Nam-Hyung
    • Proceedings of the KSAR Conference
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    • 2001.03a
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    • pp.12-12
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    • 2001
  • To get insight into the nature of foreign mitochondria and syngamy during mammalian fertilization we compared fertilization processes in porcine oocytes following microinjection of porcine or mouse spermatozoa. Pronuclear movement, sperm mitochondria, and DNA synthesis were imaged with propidium iodide, mitotracker, and BrdU under confocal laser scanning microscope. Intracytoplasmic injection of either porcine or mouse spermatzoon activated porcine oocytes without additional parthengenetic stimulation. Foreign mitochondria in either mouse or porcine sperm midpiece were introduced into porcine oocytes following sperm injection, but rapidly disappeared from the actively developing porcine oocytes. BrdU experiment showed new DNA synthesis in porcine oocytes following injection of mouse spermatozoon or sperm head. At 24 h after injection of mouse isolated sperm head or a spermatozoon, mitoic metaphase was seen in oocyte, but they did not go to normal cell division (Table). These results suggest that pronuclear formation, foreign mitochondria disruption, DNA synthesis and syngamy formation during fertilization are not species specific processes.(Table Omitted).

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Application of Supercritical Fluid in Energetic Materials Processes (화약제조 공정의 초임계 유체 응용)

  • Song, Eun-Seok;Kim, Hwa-Yong;Kim, Hyoun-Soo;Lee, Youn-Woo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.9 no.3
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    • pp.77-87
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    • 2006
  • Micro- or nano-size particles are required to improve the combustion efficiency and stability in the case of solid explosives and propellants. The micro-structural properties of an energetic material strongly influence the combustion and explosion behavior. However, the traditional size reduction techniques, including milling, are not suitable for production of ultra-fine size particles. As an alternative to the traditional techniques, various re-crystallization processes based on supercritical fluids have recently been proposed. Supercritical fluids are fluids at temperatures and pressures above their critical point. In principle, they do not give problems of solvent contamination as they are completely released from the solute when the decompression occurs. Rapid Expansion Supercritical Solutions(RESS) and Supercritical Anti-Solvent Process(GAS/SAS) are representatives of a nano-size particle formation process of energetic materials using supercritical fluids. In this work, various fine particle formation processes using supercritical fluids are discussed and the results are presented.

An Experimental Study on Diesel Spray Dynamics and Auto-Ignition Characteristics to use Rapid Comperssion Machine (RCM을 이용한 디젤 분무 거동 및 자발화 특성에 관한 실험적 연구)

  • Ahn, J.H.;Kim, H.M.;Shin, M.C.;Kim, S.W.
    • Journal of ILASS-Korea
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    • v.8 no.3
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    • pp.33-40
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    • 2003
  • The low-emission and high-performance diesel combustion is an important issue in the combustion research community, In order to understand the detailed diesel flame involving the complex physical processes, it is quite desirable to diesel spray dynamics, auto-ignition and spray flame propagation. Dynamics of fuel spray is a crucial element for air-fuel mixture formation, flame stabilization and pollutant formation, In the present study, the diesel RCM (Rapid Compression Machine) and the Electric Control injection system have been designed and developed to investigate the effects of injection pressure, injection timing, and intake air temperature on spray dynamics and diesel combustion processes, In terms of the macroscopic spray combustion characteristics, it is observed that the fuel jet atomization and the droplet breakup processes become much faster by increasing the injection pressure and the spray angle, With increasing the cylinder pressure, there is a tendency that the of spray pattern in the downstream region tends to be spherical due to the increase of air density and the corresponding drag force, Effects of intake temperature and injection pressure on auto-ignition is experimently analysed and discussed in detail.

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An Experimental Study on Diesel Spray Dynamics and Auto-Ignition Characteristics in the Rapid Compression Machine (RCM을 이용한 디젤 분무거동 및 자발화 특성에 관한 연구)

  • Kang, P.J.;Kim, H.M.;Kim, Y.M.;Kim, S.W.
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.447-452
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    • 2000
  • The low-emission and high-performance diesel combustion is an important issue in the combustion research community. In order to understand the detailed diesel flame field involving the complex Physical Processes, It Is quite desirable to study diesel spray dynamics, auto-ignition and spray flame propagation. Dynamics of fuel spray is a crucial element for air-fuel mixture formation flame stabilization and pollutant formation. In the present study, the diesel RCM (Rapid Compression Machine) and the Electric Control injection system have been designed and developed to investigate the effects of injection Pressure, injection timing, and intake air temperature on spray dynamics and diesel combustion processes. In terms of the macroscopic spray combustion characteristics it is observed that the fuel jet atomization and the droplet breakup processes become much faster by increasing the injection pressure and the spray angle. With increasing the cylinder pressure there is a tendency that the shape of spray pattern in the downstream region tends to be spherical due to the increase of air density and the corresponding drag force. Effects of intake temperature and injection pressure on auto-ignition is experimently analysed and discussed in detail.

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Effects of the Preheating Treatments of Raw Ginseng in the Model System on the Synthesis of the Maillard Type-Browning Reaction Products of Red Ginseng

  • Suzuki, Yukio;Choi, Kang-Ju;Uchida, Kei;Ko, Sung-Ryong
    • Journal of Ginseng Research
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    • v.28 no.3
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    • pp.136-142
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    • 2004
  • During our investigations on the relationship between the browning reaction of ginseng root and two compounds (arginyl-fructosyl-glucose and arginyl-fructose) in the model system of steaming and heat-drying processes for the preparation of red ginseng, the preheating treatment of main roots of raw ginseng at 60∼70$^{\circ}C$ prior to the steaming and heat-drying processes was found to bring about the gelatinization of starch granules. The enzymatic hydrolysis of gelatinized starch to maltose, a marked formation of maltose, and the increase of both free arginine and total amino acids, resulting the acceleration of the Maillard type-browning reaction of ginseng root during the steaming and heat-drying processes, and the rise of brown color intensity of red ginseng. These results show that the preheating treatment may be effective for the decrease of inside white of red ginseng.

Investigation on the Practical Use of Gas Hydrate in Gas Industry (가스하이드레이트 산업시스템 실용화 현황 및 동향 분석)

  • Gwon, Ok-Bae;Sin, Chang-Hun;Park, Seung-Su;Han, Jeong-Min;Lee, Jeong-Hwan
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.06a
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    • pp.415-418
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    • 2006
  • In Japan, research and development were undertaken on gas hydrate-side industrial processes associated with power generation system connections that may particularly be necessary to develop gas hydrated technology-based industrial systems. In so doing, data and engineering technologies useful n formulating guidelines on design of practical process were accumulated. In addition, basic research into theoretical evidence were carried out to promote and support the development of technological elements for those processes. In basic research designed to promote and support the research and development of elemental technologies microanalyses were conducted to understand the decomposition mechanism of mixed gas hydrate. Moreover, measurement technologies that can be applied in industrial processes, such as numerical analyses and concentration ion measurement, were examined. Japan has developed a highly efficient gas hydrate formation process using micro-bubbles with a tubular reactor. Higher formation rate over conventional systems has been obtained by the process. As mentioned above, the technical problems were clarified and the economics were studied from a view point of the NGH technology in this study. The results can be applied for utilization and must contribute to popularization of gas hydrate production.

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On the Possibility of Bulk Large Diamond Single Crystal Synthesis with Hydrothermal Process

  • Andrzej M. Szymanski
    • Journal of the Mineralogical Society of Korea
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    • v.10 no.1
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    • pp.18-32
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    • 1997
  • Analysis of geological data, relating to occurrence and formation of diamonds as well as host rocks, inclined author to have different outlook on the diamond genesis and to establish a proposition on their formation at pneumatolytic-hydrothermal conditions near superficial Earth zones. Based on that theoretical foundations and experimental works, the first low-pressure and low-temperature hydrothermal diamond synthesis from water solution in pressure autoclave was executed. As a result, the natural diamond seed crystal grew bigger ad coupling of the synthetic diamond single-crystalline grains were obtained. SEM documentation proofs that parallely paragenetic crystallization of quartz and diamond, and nucleation of new octahedral diamond crystals brush take place on the seed crystal surface. Forecast of none times growth of diamond industrial application at 2000 and seventeen times at 2010 with reference to 1995, needs technology of large and pure single-crystals diamond synthesis. Growth of the stable and destressed diamond single-crystals in the pseudo-metastable diamond plot, may be realized with processes going through the long time and with participation of free radicals catalysts admixtures only. Sol-gel colloidal processes are an example of environment which form stable crystals in thermodynamically unstable conditions through a long time. Paper critically discusses a whole way of studies on the diamond synthesis, from high-pressure and high-temperature processes through chemical vapour deposition up to hydrothermal experiments.

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