• 제목/요약/키워드: relative growth

검색결과 2,241건 처리시간 0.023초

비선형 PSE를 이용한 압축성 경계층의 안정성 해석 (STABILITY ANALYSIS OF COMPRESSIBLE BOUNDARY LAYER IN CURVILINEAR COORDINATE SYSTEM USING NONLINEAR PSE)

  • ;박승오
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2007년도 추계 학술대회논문집
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    • pp.134-140
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    • 2007
  • Nonlinear parabolized stability equations for compressible flow in general curvilinear coordinate system are derived to deal with a broad range of transition prediction problems on complex geometry. A highly accurate finite difference PSE code has been developed using an implicit marching procedure. Blasius flow is tested. The results of the present computation show good agreement with DNS data. Nonlinear interaction can make the T-S fundamental wave more unstable and the onset of its amplitude decay is shifted downstream relative to linear case. For nonlinear calculations, rather small difference in initial amplitude can produce large change during nonlinear region. Compressible secondary instability at Mach number 1.6 is also simulated and showed that 1.1% initial amplitude for primary mode is enough to trigger the secondary growth.

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Note Biological Control of Fusarium Wilt in Tomato by Plant Growth-Promoting Yeasts and Rhizobacteria

  • Abo-Elyousr, Kamal A.M.;Mohamed, Hashem M.
    • The Plant Pathology Journal
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    • 제25권2호
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    • pp.199-204
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    • 2009
  • Three plant growth-promoting yeasts and two rhizobacteria were tested for controlling tomato wilt caused by Fusarium oxysporum f. sp. lycopersici under green-house and field conditions. Under greenhouse and field conditions, all treatments were significantly reduced disease severity of tomato wilt relative to the infected control. The highest disease reductions in pots (75.0, 67.4%) and field (52.5, 42.4%) were achieved by Azospirillum brasilense and Bacillus subtilis compared to infected control. Under field condition all treatments produced the highest tomato yield compared to the control plants inoculated with the pathogen.

모잘록병의 생물학적 방제를 위한 유효 미생물 선발방법 및 효과 (Screening and effect of antagonists for biological control of plant pathogen)

  • 이백석;최성원;최기현;이재호;김은기
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2002년도 생물공학의 동향 (X)
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    • pp.386-389
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    • 2002
  • 식물의 토양전염병을 유발하는 P. aphanidermatum 및 R. solani에 대한 길항력, 생장속도 및 표면장력 감소를 고려한 RPI (relative performance indices) 기법을 이용하여 90 여개 후보균 중 #16 길항균을 선정하였다. 선정된 Bacillus sp. #16은 16S rRNA 서열을 분석한 후 GenBank에서 비교한 결과 B. subtilis DSM10과 99% 유사성을 보였다. 또한 pot test 결과 오이 모잘록병에 대해 우수한 방제가를 보였다.

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Country Analysis: Algeria

  • Mehyaoul, Quafaa
    • Asian Journal of Business Environment
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    • 제5권3호
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    • pp.29-31
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    • 2015
  • Purpose - The purpose of this country analysis is to examine its current state: economically, politically, legally, and ethically, and look at small and medium Algerian businesses to identify any issues that could hinder economic and business performance and growth. Research Design, and Methodology - This is a case study, an analytical approach, which focuses on exploring and analyzing different aspects of Algeria. Results - Since 2008, the Algerian economy has experienced a relative slowdown due to falling oil and gas prices and the economic recessions of its main trading partners, in particular, European countries. Algeria has still not managed to diversify its economy or establish competitive industrialization at the international level; it has had difficulty shifting from its economic dependence on hydrocarbons. Algerian businesses continue to face obstacles and constraints, penalized in their performance and prevented from success in a dense and competitive global marketplace. Conclusion - The Algerian economy and Algerian businesses have shown positive performance and growth over the last few decades. However, issues exist that may hinder both business and economic progress in the future.

Cultural characterization of probiotic Lactobacillus sakei BK19

  • Yang , Byung Gyoo;Song , Choon Bok;Yeo , In Kyu;Lee , Kyoung Jun;Park , Geun Tae;Lee, Sang Hyeon;Son, Hong Joo;Heo, Moon Soo
    • 한국어병학회지
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    • 제16권2호
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    • pp.119-123
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    • 2003
  • We have selected an valuable pmbiotic strain; Lactobacillus sakei BK19 which has wide antagonic spectrum against fish pathogens . Present study investigated cultural characterization of L. sakei BK19 including pH tolerance , susceptibility of antibacterial agents and growth pattern with different environment such as nutritions, temperature and salinity. L. sakei BK19 showed Significantly higher resistance at low pH(around pH 4) environment and relative high antibiotic tolerance . In the study of optimal culture condition, maltose and saccharose provided the optimal nutritional culture condition while lactose and mannitol were unable to supply its carbon source for the fermentation of L. sakei BK19. Moreover. L. sakei BK19 showed good growth at the temperature range of 15 to $45^{o}C$ und the NaCl concentration of 0 to 7%. Hence, this particular probiotic strain may be benificial both in seawater and fresh weter conditions.

암석의 변형 및 파괴거동의 해석을 위한 균열모형 개발에 관한 연구 (Development of a Mechanical Crack Model to Analyze Deformation and Failure Mechanism of Rock)

    • 터널과지하공간
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    • 제8권2호
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    • pp.96-106
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    • 1998
  • Rock contains discontinuities at all scales. These discontinuities make rock behave in a complex way. This paper discusses a new approach to underground design based on the theory of rock fracture mechanics. The mechanism of deformation and failure of coal was studied by observing the distributions of length, orientation and spacing of the pre-existing as well as stress-induced cracks. Different types of crack information. The crack information is dependent on the scale used. The cracks propagate along the intersections of the pre-existing cracks, and both extensile and shear crack growth occur depending on the direction of the load relative to the bedding planes. An analytical model that takes into account both shear and extensile crack growth was developed to predict the nonlinear stress-strain behavior of coal including strain-hardening and strain-softening.

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How Distinct are Technology-Based Start-Ups in India? Features, Policies and Evolving Ecosystems

  • Subrahmanya, MH Bala
    • Asian Journal of Innovation and Policy
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    • 제7권1호
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    • pp.30-54
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    • 2018
  • Tech start-ups and their ecosystems are gaining increasing prominence globally and so are in India, due to their potential to contribute to employment generation, innovations, productivity, national income and exports. Against this backdrop, this article analyzes the key characteristics of tech start-ups relative to traditional start-ups and modern start-ups in India. Further, the salient features of tech start-up promotion policies initiated by the government of India and government of Karnataka as well as the current regional and sectoral distribution of start-ups is elucidated. Subsequently, the structure and components of entrepreneurial ecosystems currently under evolution in the metro cities of India are examined. Finally, the key factors contributing to the growth of different ecosystem components and its implications for the future growth of tech start-ups are outlined.

(Nd, Dy)-Fe-B 분말의 소결특성 및 상변화 연구 (Sintering Behavior and Phase Analysis of (Nd, Dy)-Fe-B Powder)

  • 김세훈;김진우;김영도
    • 한국분말재료학회지
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    • 제17권2호
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    • pp.154-159
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    • 2010
  • In this study, the sintering behavior of (Nd, Dy)-Fe-B powder which fabricated by strip-casting was investigated with various sintering temperatures and holding times. The relative density over 99% could be obtained by both sintering at $1070^{\circ}C$ for 1h and sintering at $970^{\circ}C$ for 20h. The grain growth was observed in sintered specimen at $1050^{\circ}C$ compared to one at $970^{\circ}C$. The isothermal sintering process below $1000^{\circ}C$ led to suppress grain growth showing the improved magnetic properties. The phase transformation of Nd-rich was confirmed by X-ray diffraction pattern.

상호 확산 반응 중의 생성상 제어 (Product Phase Control During Interdiffusion Reactions)

  • 박준식;김지훈
    • 한국주조공학회지
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    • 제26권1호
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    • pp.27-33
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    • 2006
  • Phase evolutions involving nucleation stages together with diffusional growth have been examined in order to provide a guideline for determining rate limiting stages during phase evolutions. In multiphase materials systems in coatings, composites or multilayered structures, diffusion treatments often result in the development of metastable/intermediate phases at the reaction interfaces. The development of metastable phases during solid state interdiffusion demonstrates that the nucleation reaction can be one controlling factor. Also, the concentration gradient and the relative magnitudes of the component diffusivities provide a basis for a phase selection and the application of a kinetic bias strategy in the phase selection. For multicomponent alloy systems, the identification of the operative diffusion pathway is central to control phase formation. Experimental access to the nucleation and growth stage is discussed in thin film multi layers and bulk samples.