• Title/Summary/Keyword: growth steps

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Color Nanotube Field Emission Displays for HDTV

  • Dean, K.A.;Coll, B.F.;Dinsmore, A.;Howard, E.;Hupp, M.;Johnson, S.V.;Johnson, M.R.;Jordan, D.C.;Li, H.;Marshbanks, L.;McMurtry, T.;Tisinger, L.Hilt;Wieck, S.;Baker, J.;Dauksher, W. J.;Smith, S.M.;Wei, Y.;Weston, D.;Young, S.R.;Jaskie, J.E.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1003-1007
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    • 2005
  • We demonstrate color video displays driven by carbon nanotube electron field emitters. These nanotubes are incorporated into the device by selective growth using low temperature chemical vapor deposition. The device structure is simple and inexpensive to fabricate, and a 45 V switching voltage enables the use of low cost driver electronics. The prototype units are sealed 4.6” diagonal displays with 726 um pixels. They represent a piece of a 42” diagonal 1280x720 high definition television. The carbon nanotube growth process is performed as the last processing step and creates nanotubes ready for field emission. No activation post-processing steps are required, so chemical and particulate contamination is not introduced. Control of the nanotube dimension, orientation, and spatial distribution during growth enables uniform, highquality, color video performance.

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Culture of Rat Salivary Acinar Cells (백서 타액선 선포 세포의 배양)

  • Lee, Sung-Woo;Han, Song;Kho, Hong-Seop
    • Journal of Oral Medicine and Pain
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    • v.24 no.2
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    • pp.163-169
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    • 1999
  • We investigated the culture condition and effects of various growth factors on the culture of salivary gland acinar cells. Male, Sprague-Dawley rats (about 6 weeks old) were sacrificed and their submandibular, sublingual, and parotid glands were used as specimens. High oxygen level more than 90% and coating of Matrigel on culture dish were important factors to help increase the survival time of acinar cells, Proper concentration of enzymes such as collagenase and hyaluronidase during isolation steps was also important. Addition of various growth factors such as dexamethasone, insulin, transferrin, selenous acid, reduced glutathione, epidermal growth factor, isoproterenol, and putrescine in culture medium helped to increase lifetime of cultured salivary acinar cells.

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Numerical Analysis for the Soot Formation Processes in Acetylene-Air Nonpremixed Turbulent Jet Flame (아세틸렌/공기 비예혼합 난류 제트화염의 Soot 생성에 대한 수치해석)

  • 김후중;김용모;윤명원
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.6
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    • pp.80-89
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    • 2002
  • The flame structure and soot formation in Acetylene-Air nonpremixed jet flame are numerically analyzed. We employed two variable approach to investigate the soot formation and oxidation processes. The present soot reaction mechanism involves nucleation, surface growth, particle coagulation, and oxidation steps. The gas phase chemistry and the soot nucleation, surface growth reactions are coupled by assuming that the nucleation and soot mass growth has the certain relationship with the concentration of pyrene and acetylene. We also employed laminar flamelet model to calculate the thermo-chemical properties and the proper soot source terms from the information of detailed chemical kinetic model. The numerical and physical model used in this study successfully predict the essential features of the combustion processes and soot formation characteristics in the reaction flow field.

The Effect of technical competence according to commercialize the company's technology incubator support and management performance stage (창업보육기업의 기술사업화에 따른 기술역량이 지원과 경영성과단계에 미치는 영향)

  • Jeon, In-Oh
    • The Journal of the Korea Contents Association
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    • v.12 no.9
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    • pp.325-340
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    • 2012
  • The present study, the technology commercialization through support of government enterprise incubator, incubator companies examined, and the support of the government in accordance with the technical competence necessary steps management performance steps, support conditions required were investigated. Government support of technology commercialization support business performance necessary steps to support the needs of the incubator companies and step conditions. Therefore, need funding and funding support, and the time and duration of the condition of the steps in the support business performance, the conduct of the government's support is the most needed step, showed a new growth engine projects of the application and selection screening, sector was.

Comparison of Fermentation Characteristics of Korean Traditional Alcoholic Beverages Prepared by Different Brewing Methods and Their Quality Changes after Aging (전통주의 제조방법별 발효 특성 및 숙성후 품질변화 비교)

  • Kim, In-Ho;Park, Wan-Soo;Koo, Young-Jo
    • Journal of the Korean Society of Food Culture
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    • v.11 no.4
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    • pp.497-506
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    • 1996
  • Fermentation characteristics and quality changes of the typical Korean traditional alcoholic beverages (Kwahaju, Sokokju, Baikhaju, Samhaeju and Hosanchun) were investigated during fermentation and after aging, respectively. They were prepared by their own brewing methods with respect to the same contents of rice and Nuruk (Korean-style bran koji). The consumed total sugar content of the alcoholic beverages (Sokokju, Baikhaju, Samhaeju and Hosanchun) which were brewed with the multiple input steps of seed mash and raw material (ABMIS) was higher than that of the alcoholic beverage (Kwahaju) which was brewed with the single input step (ABSIS). The pH values of all the beverages were similar and were ranged from 3.2 to 3.6. The acidity of ABMIS were lower than that of ABSIS, but alcohol concentration of ABMIS were higher. The fermentation period of the alcoholic beverages with triple input steps was the longest among them. The inner temperature and microbial growth in all the beverages increased at each of input steps of the raw materials. Fusel oil content of ABMIS was lower than that of ABSIS. Major components of the fusel oil were iso-amyl alcohol, iso-butanol, n-propanol, ethyl acetate and acetaldehyde, and its minor components were methanol and n-butanol. The results on quality changes of the alcoholic beverages after aging showed increase of alcohol in ABMIS, but decrease of sugar and acidity. Fusel oil contents of Kwahaju and Samhaeju decreased to be ranged from 3.1% to 13.9% after aging, but those of Sokokju, Baikhaju and Hosanchun increased to be ranged from 10.9% to 23.0%. Sensory evaluation of ABMIS showed better scores than that of ABSIS. It was suggested that the brewing method with multiple input steps of seed mash and raw material was one of the methods to increase fermentation efficiency for brewing the Korean traditional alcoholic beverages.

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Bacterial determinants involved in the induction of systemic resistance ana plant growth promotion in tobacco by Pseudomonas chlororaphis O6.

  • Han, Song-Hee;Cho, Baik-Ho;Kim, Young-Cheol
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 2003.10a
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    • pp.101.2-102
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    • 2003
  • The ability of P. chlororaphis O6 to induce resistance to Erwinia carotovora subsp. carotovara SCCI and to promote growth in tobacco was demonstrated in microtiter assays on plants pre-inoculated at the root level with the bacteria before challenge with the leaf pathogen. To identify th bacterial determinants involved in induced systemic resistance and plant growth promotion, cell culture of O6 grown in King's medium B was fractionated with organic solvents and purified using various columns. in vivo and in vitro assays with samples from successive fractionation steps of the O6 supernatant led to the conclusion that antibacterial compounds were observed in aqueous layer, and to the isolation of fractions containing metabolites that retained most of the resistance-inducing activity (70:30, methanol:water) and the plant growth promotion (80:20 and 90:10, methanol:water) after ODS column chromatography. Although these molecules remain to be purified further and structurally characterized, its isolation is an addition to the range of determinants from plant growth-promoting rhizobacteria known to stimulate plant defence.

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Evolution of surface morphology and roughness in Si and $_{0.7}$Ge$_{0.3}$ thin fimls (Si 및Si$_{0.7}$Ge$_{0.3}$ 박막의 표현형태 및 조도의 전개)

  • 이내웅
    • Journal of the Korean institute of surface engineering
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    • v.31 no.6
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    • pp.345-358
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    • 1998
  • The evolution of surface roughness and morphology in epitaxial Si and $Si_{0.7}Ge{0.3}$ alloys grown by UHV opm-beam sputter deposition onto nominally-singular, [100]-, and [110]-mi-scut Si(001) was investigated by stomic force microscopy and trasmission electron microscopy. The evolution of surface roughness of epitaxial Si films grown at $300^{\circ}C$ is inconsistent with conventional scaling and hyperscaling laws for kineti roughening. Unstable growth leading to the formation of mounds separated by a well-defined length scale is observed on all substrates. Contraty to previous high-temperature growth results, the presence of steps during deposition at $300^{\circ}C$ increases the tendency toward unstable growth resulting in a much earlier development of mound structures and larger surface roughnesses on vicival substrates. Strain-induced surface roughening was found to dominate in $Si_{0.7}Ge{0.3}$ alloys grown on singular Si(001) substrates at $T_S\ge450^{\circ}C$ where the coherent islands are prererentially bounded along <100> directions and eshibt {105} facetting. Increasing the film thickness above critical values for strain relaxation leads to island coalescence and surface smoothening. At very low growth temperatures ($T_s\le 250^{\circ}C$), film surfaces roughen kinetically, due to limited adatom diffusiviry, but at far lower rates than in the higher-temperature strain-induced regime. There is an intermediate growth temperature range, however, over which alloy film surfaces remain extremely smooth even at thicknesses near critical values for strain relaxation.

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Analysis of Industry Growth and Employment Effect in the Korean Manufacturing Sector by Regions (제조업종의 지역별 산업성장 및 고용효과 분석)

  • Koo, Hoonyoung;Min, Daiki
    • Korean Management Science Review
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    • v.34 no.1
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    • pp.15-25
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    • 2017
  • We evaluated industry growth and employment effects of every possible pairs of 22 manufacturing sectors and 16 regions (i.e, 352 region-sectors). We used annual data of manufacturing sectors from 2008 to 2014 for the evaluation. The evaluation comprises of two steps; We first find several region-sectors that outperform others with respect to the effects of industry growth and employment, which are measured by location quotient analysis, shift share method, employment to GDP ratio and employment elasticity. In addition, cross-efficiency analysis follows to classify region-sector pairs into two sub-categories : efficient region-sectors that deserve to hold the current level of investments and inefficient region-sectors where we should consider efficiency improvements. To examine the efficiency, R&D investment, employment size, and capital investment were used as input factors and production volume, added value, changes in employment size, changes in annual salary per capita were used as output factors. For region-sector pairs that have outstanding growth and employment effects but are inefficient, we employed a CCR DEA model and analyzed how much to adjust the values of input and output factors to improve the efficiency scores. The analysis results showed that inefficiency is mainly due to several factors such as R&D investment, changes in employment size and changes in annual salary per capita.

Effect of $NH_3$ on the Synthesis of Carbon Nanotubes Using Thermal Chemical Vapor Deposition

  • Cho, Hyun-Jin;Jang, In-Goo;Yoon, So-Jung;Hong, Jin-Pyo;Lee, Nae-Sung
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.1219-1224
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    • 2006
  • This study investigates the effect of $NH_3$ gas upon the growth of carbon nanotubes (CNTs) using thermal chemical vapor deposition. It is considered that the CNT synthesis occurs mainly through two steps, clustering of catalyst particles and subsequent growth of CNTs. We thus introduced $NH_3$ during either an annealing or growth step. When $NH_3$ was fed only during annealing, CNTs grew longer and more highly crystalline with diameters unchanged. An addition of $NH_3$ during growth, however, resulted in shorter CNTs with lower crystallinity while increased their diameters. Vertically aligned, highly populated CNT samples showed poor field emission characteristics, leading us to apply post-treatments onto the CNT surface. The CNTs were treated by adhesive tapes or etched back by dc plasma of $N_2$ to reduce the population density and the radius of curvatures of CNTs. We discuss the morphological changes of CNTs and their field emission properties upon surface treatments.

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Mathematical Modeling with Cell Morphology and Its Application to Fed-batch Culture in Cephalosporium Fermentation (Cephalosporium 발효시 균체의 형태학적 측면을 고려한 수학적 모델링 및 유가식 배양에의 응용)

  • 김의용;유영제
    • Microbiology and Biotechnology Letters
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    • v.19 no.5
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    • pp.521-535
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    • 1991
  • A kinetic model incorporating cell morphology in cephalosporin C biosynthesis by Cephalosporium amemoniurn was developed. The double-substrate Double-substrate kinetic model was used to describe cell growth. Methionine controlled the rate of growth while glucose ultimately controlled the extent of growth. The changes in specific product formation rate were associated with morphologenesis, especially cell differentiation. To increase the productivity of cephalosporin C, the proposed model equations were applied to a fed-batch culture. The algorithm to optimize the fed-batch culture consists of two steps; cell growth was maximized in the growth phase and then cephalosporin C production was maximized in the production phase. The increase of about 33% in the cephalosporin C titre was obtained by the optimal feeding scheduling in comparison with that of batch culture.

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