• Title/Summary/Keyword: Pure sciences

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Electrophoretic variations of enzyme, GDH (NADP-dependent glutamate dehydrogenase)(EC. 1.4.1.4) in characterizing clones and isolates of Malaysian Plasmodium falciparum

  • Ang, Hooi-Hoon;Chan, Kit-Lam;Mak, Joon-Wah
    • Parasites, Hosts and Diseases
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    • v.34 no.3
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    • pp.211-213
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    • 1996
  • Malaysian, Ajricn and Thai PZQsmodiumJnkipamm isolates were cultured in uiko by the Tracer and Jensen method (1976, 1977) and were later cloned by the limiting dilution method (Rosario, 1981), Forty-eight clones were obtained and were characterized by electrophoretic variations of GDH (NADP-dependent glutamate dehydrogenase)(EC. 1.4.1.4). It was found that they were pure clones because they possessed either GDH-1 or GDH-2 unlike their parent isolates which exhibited both GDH-1 and GDH-2.

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Solvothermal synthesis and characterization of silver nanoparticles

  • Guptha, K. Venkateswara;Nesaraj, A. Samson
    • Advances in nano research
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    • v.2 no.3
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    • pp.147-155
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    • 2014
  • Among the various nanoparticles reported for commercial applications, considerable interest has been generated by the use of silver nanoparticles. Owning to extremely small size, silver nanoparticles exhibit enhanced properties when compared with the bulk material. In this research work, silver nanoparticles were prepared by the reduction of silver salt with a reducing agent by a solvothermal method using different solvent mediums such as ethanol, hexane, toluene and acetone with water. The prepared silver nanoparticles were characterized systematically by X-ray diffraction (XRD), particle size analysis and scanning electron microscope (SEM). The results revealed the formation of pure silver phase and nano-sized particles. Among the different solvent mediums used, the silver nanoparticles prepared by hexane and water as solvent mixture resulted in very low particle size.

Production of Lactic Acid from Cheese Whey by Batch Culture of Lactobacillus sp. RKY2

  • Kim, Hyang-Ok;Wee, Young-Jung;Yun, Jong-Sun;Ryu, Hwa-Won
    • 한국생물공학회:학술대회논문집
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    • 2005.04a
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    • pp.181-185
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    • 2005
  • We investigated the fermentative production of lactic acid from cheese whey and corn steep liquor as cheap raw materials using Lactobacillus sp. RKY2 to reduce the manufacturing cost of lactic acid. Lactic acid yields were obtained at more than 0.98 g/g from medium containing whey lactose. Lactic aid productivities and yields obtained from whey lactose were slightly higher than those obtained from pure lactose. The final concentration of lactic acid increased with increase, in whey lactose concentration, whereas the lactic acid productivity decreased probably due to substrate inhibition. The fermentation efficiencies were improved by addition of more corn steep liquor to the medium.

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Lateral Penetration of Water in Ray Parenchyma Cells of Castanea crenata

  • Ahmed, Sheikh Ali;Chong, Song-Ho;Chun, Su-Kyoung
    • Journal of the Korea Furniture Society
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    • v.19 no.2
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    • pp.137-140
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    • 2008
  • This experiment states the ultra pure distilled water penetration depth through ray parenchyma cell in radial direction of Castanea crenata. Heartwood penetration depth was 1.16 times lower than the depth in softwood and that difference was found statistically significant at 75.2 second of penetration. Following go-stop-go cycle, water penetrated in the ray parenchyma cell. At the beginning this speed was high and then it was decreased slowly. Water penetration depth result was compared with alcohol penetration depth. It was found that water penetration in ray parenchyma was found lower than alcohol due to the low surface tension of water.

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Longitudinal Penetration of Water through the Vessel and Wood Fiber in Castanea crenata

  • Ahmed, Sheikh Ali;Chun, Su-Kyoung
    • Journal of the Korea Furniture Society
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    • v.19 no.2
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    • pp.111-115
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    • 2008
  • An experiment was conducted to know ultra-pure distilled water penetration depth through large vessel, small vessel, latewood fiber and earlywood fiber in longitudinal direction of Castanea crenata. In heartwood, latewood fiber transported water more than large and small vessel. While in sapwood, small vessel conduction depth was found the highest. Penetration depth of water after 15.0 seconds, no significant difference was observed among earlywood fiber, latewood fiber and earlywood vessel. Whilst in heartwood, no statistical difference was observed among earlywood fiber, latewood fiber and earlywood vessel. At the beginning, the speed of water penetration was high and then gradually decreased.

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An Experimental Study on Lift Force Generation Resulting from Spanwise Flow in Flapping Wings

  • Hong, Young-Sun
    • International Journal of Aeronautical and Space Sciences
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    • v.7 no.2
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    • pp.86-103
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    • 2006
  • Using a combination of force transducer measurement to quantify net lift force, high frame rate camera to quantify and subtract inertial contributions, and Digital Particle Image Velocimetry (DPIV) to calculate aerodynamic contributions in the spanwise plane, the contribution of spanwise flow to the generation of lift force in wings undergoing a pure flapping motion in hover is shown as a function of flapping angle throughout the flapping cycle. These experiments were repeated at various flapping frequencies and for various wing planform sizes for flat plate and span wise cambered wings. Despite the previous identification of the importance of span wise fluid structures in the generation of lift force in flapping wings throughout the existing body of literature, the direct contribution of spanwise flow to lift force generated has not previously been quantified. Therefore, in the same manner as commonly applied to investigate the chordwise lift distribution across an airfoil in flapping wings, spanwise flow due to bulk flow and rotational fluid dynamic mechanisms will be investigated to validate the existence of a direct component of the lift force originating from the flapping motion in the spanwise plane instead.

Prediction of Effective Material Properties for Triaxially Braided Textile Composite

  • Geleta, Tsinuel N.;Woo, Kyeongsik;Lee, Bongho
    • International Journal of Aeronautical and Space Sciences
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    • v.18 no.2
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    • pp.222-235
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    • 2017
  • In this study, finite element modeling was used to predict the material properties of tri-axially braided textile composite. The model was made based on an experimental test specimen which was also used to compare the final results. The full interlacing of tows was geometrically modelled, from which repeating parts that make up the whole braid called unit cells were identified based on the geometric and mechanical property periodicity. In order to simulate the repeating nature of the unit cell, periodic boundary conditions were applied. For validation of the method, a reference model was analyzed for which a very good agreement was obtained. Material property calculation was done by simulating uniaxial and pure shear tests on the unit cell. The comparison of these results with that of experimental test results showed an excellent agreement. Finally, parametric study on the effect of number of plies, stacking type (symmetric/anti-symmetric) and stacking phase shift was conducted.

Landscape Ecology Concept, Principles and Its Rlation to Monothematic (e.g. Vegetation) Survey (경관생태학의 개념, 원리 및 식생조사와의 관계)

  • Isaak, S. Zonneveld
    • The Korean Journal of Ecology
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    • v.21 no.4
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    • pp.357-372
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    • 1998
  • Land (scape) ecology is a trans-disciplinary science studying the related systems at the earth surface, in their visual, structural and functional aspects. it serves as an umbrella under which abiotic and biotic sciences, in an integrated way, study the for each relevant land attributes and their interrelations. The spatial aspects of these relations have a special interest. Landscape ecology my have a pure scientific purpose, but usually is executed in an applied context, related to land evaluation for land use and conservation. Depending on the aim and application of the study, one of the land attributes may get special attention. Vegetation mapping may contribute to landscape ecological study but also benefit from it especially in case of reconnaissance surveys. This is because in less detailed surveys of any land attribute, like land form, soil, vegetation, one must necessarily apply landscape ecological principles in the survey methodology, including remote sensing.

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Bilingual Voice Conversion Using Frequency Warping on Formant Space (포만트 공간에서의 주파수 변환을 이용한 이중 언어 음성 변환 연구)

  • Chae, Yi-Geun;Yun, Young-Sun;Jung, Jin Man;Eun, Seongbae
    • Phonetics and Speech Sciences
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    • v.6 no.4
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    • pp.133-139
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    • 2014
  • This paper describes several approaches to transform a speaker's individuality to another's individuality using frequency warping between bilingual formant frequencies on different language environments. The proposed methods are simple and intuitive voice conversion algorithms that do not use training data between different languages. The approaches find the warping function from source speaker's frequency to target speaker's frequency on formant space. The formant space comprises four representative monophthongs for each language. The warping functions can be represented by piecewise linear equations, inverse matrix. The used features are pure frequency components including magnitudes, phases, and line spectral frequencies (LSF). The experiments show that the LSF-based voice conversion methods give better performance than other methods.

Optimal Antenna Angles for Data Transmission Systems Using Multiple Linear Polarized Antennas (선형 편파 다중 안테나를 사용하는 데이터 전송 시스템을 위한 최적 안테나 각도)

  • Yang, Yusik;Jeong, Da Hun;Lim, Hyo-Sang;Park, Yoon Ok;Kim, Jaekwon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.11
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    • pp.976-978
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    • 2013
  • In this paper, we address data transmission systems using multiple linear polarized antennas over pure line-of-sight (LoS) wireless channels. We investigate the impact of antenna angles from the perspective of both channel capacity and error performance. We show that the optimal angles from the two perspectives are different, and evaluate the performance of the two optimal angles.