• Title/Summary/Keyword: Growth of Solid

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A theoretical analysis on the inviscid stagnation-flow solidification problem (비점성 정체 유동 응고 문제에 대한 이론적 해석)

  • 유주식
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.1
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    • pp.1-11
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    • 2000
  • This study investigates the problem of phase change from liquid to solid in the inviscid stagnation flow. The solution of dimensionless governing equations is determined by the three dimensionless parameters of (temperature ratio/conductivity ratio), Stefan number, and diffusi-vity ratio. The solution at the initial stage of freezing is obtained by expanding it in powers of time, and the final equilibrium state is determined from the steady-state governing equations. The equilibrium state is dependent on (temperature ratio/conductivity ratio), but is independent of Stefan number and diffusivity ratio. The effect of fluid flow on the pure conduction problem can be clearly seen from the solution of the initial stage and the final equilibrium state, and the characteristics of the solidification process for all the dimensionless parameters are elucidated.

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Topical delivery of smad3 antisense using cationic solid lipid nanoparticle(SLN): therapeutic potential use and prevention of keloids

  • Jin, Su-Eon;Park, Jeong-Sook;Kim, Chong-Kook
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.248.1-248.1
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    • 2003
  • Keloids are characterized by abnormal proliferation of fibroblasts and overproduction of collagen. Recently, it is reported that transforming growth factor beta (TGFb) and its signaling molecule, SMAD3 are related to the mitogenic effect of fibroblasts and a stimulatory factor for collagen synthesis. Cationic SLN was developed to improve the complex formation of DNA/SLN and enhance the uptake efficiency to cells. SLN was formulated by DC-Chol, DOPE, trimyristin as a solid core and other surfactant. The physical properties of the SLN and the ATS-SLN complex were characterized. (omitted)

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Combination Algorithm of a Material for Marble Solid Effects

  • Park, Tae-Jin;Park, Man-Gon
    • Journal of Korea Multimedia Society
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    • v.7 no.12
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    • pp.1700-1707
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    • 2004
  • Nowaday, market size of digital image in world around is looks to rapidly growth. For this, Texture mapping has traditionally been used to add realism to computer graphics images. Therefore to make our image realistic, we need to give the various kind of objects material parameter and environment lighting. To present the completed marble we use passing back algorithm and combination with channel of a material. In experimental result of this paper that application by passing back algorithm and varying the parameter such as scale, period, distortion, octaves of noise make showing the superiority of optimized rendering of spheres and perfect another marble effects.

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Low temperature solid phase crystallization of amorphous silicon thin film by crystalline activation

  • Kim, Hyung-Taek;Kim, Young-Kwan
    • Journal of Korean Vacuum Science & Technology
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    • v.2 no.2
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    • pp.97-100
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    • 1998
  • We have investigated the effects of crystalline activation on solid phase crystallization (SPC) of amorphous silicon (a-Si) thin films. Wet blasting and self ion implantation were employed as the activation treatments to induce macro or micro crystalline damages on deposited a-Si films. Low temperature and larger grain crystallization were obtained by the applied two-step activation. High degree of crystallinity was also observed on both furnace and rapid SPC. crystalline activations showed the promotion of nucleation on the activated regions and the retardation of growth in an amorphous matrix in SPC. The observed behavior of two-step SPC was strongly dependent on the applied activation and annealing processes. It was also found that the diversified effects by macro and micro activations on the SPC were virtually diminished as the annealing temperature increased.

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Reliability Evaluation of Hydrostatic Bearing Ball Joint (정압 베어링 볼 조인트의 신뢰성 향상)

  • Jung, Dong-Soo;Park, Jong-Won
    • Journal of Applied Reliability
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    • v.12 no.3
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    • pp.165-176
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    • 2012
  • Hydrostatic bearing improves performance and life time of a product by avoiding solid friction and reducing viscosity friction with the help of creating pressure equilibrium between two faces doing relative motion. This study suggests failure analysis and test evaluation for a ball joint that adopts the hydrostatic bearing and introduces the entire process to improve reliability of the product by design improvement. A typical failure is growth of friction torque by solid friction, and its failure cause is determined and the improvement is proposed. Finally, reliability improvement is established by analysis of the results of before and after acceleration test.

Enzyme Activities and Substrate Degradation by Fungal Isolates on Cassava Waste During Solid State Fermentation

  • Pothiraj, C.;Eyini, M.
    • Mycobiology
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    • v.35 no.4
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    • pp.196-204
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    • 2007
  • The growth and bioconversion potential of selected strains growing on cassava waste substrate during solid state fermentation were assessed. Rhizopus stolonifer showed the highest and the fastest utilization of starch and cellulose in the cassava waste substrate. It showed 70% starch utilization and 81% cellulose utilization within eight days. The release of reducing sugars indicating the substrate saccharification or degradation potential of the organisms reached the highest value of 406.5 mg/g by R. stolonifer on cassava waste during the eighth day of fermentation. The protein content was gradually increased (89.4 mg/g) on the eighth day of fermentation in cassava waste by R. stolonifer. The cellulase and amylase activity is higher in R. stolonifer than A. niger and P. chrysosporium. The molecular mass of purified amylase and cellulase seemed to be 75 KDal, 85 KDal respectively.

Antitumor Activity of Lactobacillus casei against Sarcoma 180 and Lewis Lung Carcinoma in Mice (생쥐에서 Sarcoma 180 및 Lewis Lung Carcinoma에 대한 Lactobacillus casei의 항암 효과)

  • 배형석;백영진;윤영호
    • Microbiology and Biotechnology Letters
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    • v.21 no.3
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    • pp.247-255
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    • 1993
  • Antitumor activity of Lactobacillus casei YIP 9018(LC9018) was studied in mice by using sarcoma 180(S-180) and Lewis lung carcinoma (3LL). Following the eatablishment of in vivo tumor models such as ascites form S-180, solid form S-180 and 3LL for estimating antitumor activity of Lactobacilli, optimal dose and injection route of heat-killed LC9018 for supperssion of local tumor were examined. Administration of 100ng/mouse of LC9018 significantly inhibited the growth of ascites form S-180, solid form S-180 and 3LL.

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A theoretical analysis on the viscous plane stagnation-flow solidification problem (평면 점성 정체 유동 응고 문제에 대한 이론적 해석)

  • 유주식
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.10 no.3
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    • pp.260-270
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    • 1998
  • The viscous plane stagnation-flow solidification problem is theoretically investigated. An analytic solution at the beginning of solidification is obtained by expanding the temperature and thickness of solidified layer in powers of time. An exact expression for the steady-state thickness of solidified layer is also obtained. The .fluid flow toward the cold substrate inhibits the solidification process. As Stefan number becomes larger, or Prandtl number becomes smaller, the solidification is more strongly inhibited by the fluid flow. The transient heat flux at the liquid side of solid-liquid interface is increased, as Stefan number or Prandtl number is increased.

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A Study on the Tree Growth by Interface Type of XLPE (XLPE의 계면형태에 따른 트리성장에 관한 연구)

  • 김철운;김영민;김태성
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1997.04a
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    • pp.111-115
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    • 1997
  • There exists a interface among the different kinds of materials in the solid insulating ones, which effects on the insulating capability heavily. The insulating construction has been developed for each usages and take themselves into several sorts. The conjunction between CV cables have the electrical weakness of solidity and solid interface, so they were focused at the long distance-line. To this background, it is very important to get the information on the interface influencing on the insulating capability of cable and to observe its procedure. In this paper, the interface was made artificially to research the effect owing to the toughness of interface, which results in the aging and treeing proceeding was observed. The polyethylen, as is generally using for the cable, was taken in this research.

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The Effect of Elastic Anisotropy on the Shape of a Liquid Precipitate in a Wear-Resistant Fe-Base Alloy(Fe-5Cr- lMo-2Cu-0.5P-3C) (내마모 철계 소결합금(Fe-5Cr-lMo-2Cu-0.5P-3C)에서 정합변형이 액상석출물의 모양에 미치는 영향)

  • 신형상
    • Journal of Powder Materials
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    • v.1 no.1
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    • pp.60-65
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    • 1994
  • When a commercial prealloyed Fe-powder(Fe-5Cr-lMo-2Cu-0.5P-3C) is liquid phase sintered at 116$0^{\circ}C$, liquid precipitates with various shapes form within solid grains during the initial stage of sintering. The shape of a liquid precipitate changes pith the increment of their size from sphere(with radius<0.3$\mu\textrm{m}$), a transient polyhedron with more than 7 faces(1~2 $\mu\textrm{m}$), cuboid(3~5 $\mu\textrm{m}$), and finally to sphere(>5 $\mu\textrm{m}$). The shapes of liquid precipitates closely resemble the growth shapes predicted on the basis of solid-liquid interfacial energy and the coherency strain energy with anisotropic elastic constants in the diffusion zone around the precipitates.

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