• Title/Summary/Keyword: Volume stability

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A Study on the Permanent Design of Rods Each Number (Rod 호수에 따른 Permanent Design 연구)

  • Lee, Su-Hee;Cho, Koh-Mi
    • Journal of Fashion Business
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    • v.12 no.2
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    • pp.1-11
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    • 2008
  • The purpose of this study is to explore to determine the maximum volume with doing permanent waving in flat crown of the head. The method was like this. First of all, the diameter, the ratio of the circumference of a circle to its diameter and the number of rotations were analyzed same hair using permanent waving rods each number of 1$\sim$10. Secondly, the increasing rate of volume of curls number of 1$\sim$10 was analyzed. According to the result of the experiment, as the number of permanent waving rods were bigger, the ratio of the circumference of a circle to its diameter constant was increasing but the number of rotations was decreased. When the permanent waving rods of each number 1-3(Big diameter) were used, the volume was decreased. That's because there was fewer rotation compared to the diameter and was no ample combed dried hair. Due to this kind of reason, there was no perfect curling. Once number 10 permanent waving rods (most small size) was used, the shape of curling was strong and the stability was made after combed dried hair. But volume was decreased by 9% because of the cohesive power. In case of number of 4$\sim$9 rods used, volume was increased. Volume was highest when permanent waving rods was number 5 which was used combing on base both morphology and numerical value.

Effect of Diluents and Oxygen-Enrichness on the Stability of Nonpremixed Flame (산소부화와 희석제에 따른 비예혼합 화염의 안정성)

  • 배정락;이병준
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.10
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    • pp.1458-1464
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    • 2002
  • $CO_2$ is well known greenhouse gas which is the major source of global warming. Reducing $CO_2$ emission in combustion process can be achieved by increasing combustion efficiency, oxygen enriched combustion and recirculation of the emitted $CO_2$ gas. Stability of non-premixed flame in oxygen enriched environment will be affected by the amount of oxygen, kind of diluents and fuel exit velocity. The effects of these parameters on flame liftoff and blowout are studied experimentally oxidizer coflowing burner. Experiments were divided into three cases according as where $CO_2$gas was supplied. - 1) to coflowing air, 2) to fuel with 0$_2$-$N_2$ coflow, 3) to coflowing oxygen. Flame in air coflowing case was lifted in turbulent region. Flame lift and blowout in laminar region with the increase in $CO_2$ volume fraction in $CO_2$-Air mixture makes flame lift and blowout in laminar region. Increase in oxygen volume fraction makes flame stable-i.e. flame liftoff and blowout occur at higher fuel flowrates. Liftoff height was non-linear function of nozzle exit velocity and affected by the $O_2$ volume fraction. It was found that the flame in $O_2$-$N_2$ coflow case was more stable than $O_2$-$CO_2$ case, Liftoff heights vs (nozzle exit velocity/laminar burning velocity)$^{3.8}$ has a good correlation in $O_2$-$CO_2$ oxidizer case.

Stabilization of Enzyme in "Solvophobically" Controlled Polymer Microcapsules ("솔보포빅"한 고분자 마이크로 캡슐을 이용한 효소 안정화에 관한 연구)

  • Kim, Yong-Jin;Kim, Jin-Woong;Kim, Jin-Oh;Kim, Jin-Woo;Chang, Ih-Seop
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.32 no.1 s.55
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    • pp.29-33
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    • 2006
  • This article describes an enzyme stabilization method that allows the use of enzymes irrespective of environmental factors, especially heat, while maintaining their activity for a long time. We have designed enzyme microcapsules that consist of papain enzyme cores, poly(propylene glycol) interlayers, and poly(${\epsilon}-caprolactone$) walls. By confocal laser scanning microscopy measurements and the thermal stability of papain-loaded microcapsules, it is demonstrated that the papain is surrounded by a hydrophobic polyol layer and stabilized by the exclusive volume effect. In our study, improved thermal stability can be obtained by using more hydrophobic long-chained polyols, which is understood to be attributed to the effective formation of a hydrophobic polyol layer between the papain and the polymer wall by means of conformational anchoring in the interface.

Preparation and Characterization of Vapor-Grown Carbon Nanofibers-Reinforced Polyimide Composites by in-situ Polymerization (In-situ 중합법에 의한 기상성장 탄소나노섬유/폴리이미드 복합재료의 제조 및 물성)

  • Park, Soo-Jin;Lee, Eun-Jung;Lee, Jae-Rock;Won, Ho-Youn;Moon, Doo-Kyung
    • Polymer(Korea)
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    • v.31 no.2
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    • pp.117-122
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    • 2007
  • In this work, the mechanical and electrical properties, and thermal stability of vapor-grown carbon nanofibers/polyimide (VGCNFs/PI) composite film synthesized by in-situ polymerization were investigated in terms of tensile properties, volume resistivity and thermogravimetric analysis (TGA), respectively. From the results, the addition of VGCNFs with a certain amount into polyimide led to obvious improvement in tensile strength. The volume resistivity of the films was decreased with increasing the VGCNFs content and the electrical percolation threshold appeared between 1 and 3 wt% of VGCNFs content, which was probably caused by the formation of interconnective structures among the VGCNFs in a composite system. The thermal stability of the film was higher than that of pure PI one. This result indicated that the crosslinking of VGCNFs/PI Composites was enhanced by well-distribution of YGCNFs in PI resin, resulting in the increase of the thermal stability of the resulting composites.

Production of Water/n-decane Emulsion Fuel and Evaluation of Rheological Stability (물/n-데칸 에멀젼 연료의 제조 및 유변학적 안정성 평가)

  • Kim, Hye Min
    • Journal of Aerospace System Engineering
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    • v.11 no.4
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    • pp.8-14
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    • 2017
  • In this study, the production of proper emulsion fuel and the evaluation of its rheological stability in various experimental conditions were carried out. The W/O (water-in-oil) emulsion fuel was made using n-decane, pure water, and Span 80 was used as a surfactant. Increments of water volume ratio and fuel temperature were the factors, which boosted the phase separation of the emulsion fuel. Rheological characteristics for different water/oil volume ratio, temperature, and elapsed time after the fuel production were examined. As the water volume ratio in the fuel increased, the behavior of non-Newtonian fluid was observed. Viscosity declined as the fuel temperature increased due to the cohesion of water droplets in the fuel. The effect of elapsed time on viscosity was not severe for lower water ratio. However, gradual decrease of viscosity 3 hours after fuel production, in the case of ratio of 3:7, was clearly observed.

An Experimental Study on the Fluidity Properties of High Flowing Concrete Affected by Size and Volume Ratio of Coarse Aggregate (조골재 크기 및 용적비에 의한 고유동콘크리트의 각종 유동특성에 관한 실험적 연구)

  • 최세진;김완영;김진만;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.10a
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    • pp.258-261
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    • 1998
  • Aggregate is cheaper than cement and confers considerable technical advantages on concrete, which has a higher volume stability and better durability than hydrated cement paste alone. and coarse aggregate is the largest particle size out of concrete and is much affect on the fruidity, compaction and non-segregation ability of high flowing concrete. As the compaction, fillingability and shrinkage of high flowing concrete, the volume ratio of coarse aggregate is prescribed by Japanese Architectural Standard Specificateon (JASS 5) : from 0.500 to 0.500㎥/㎥. It is the aim of this study to compare and analysis the fruidity, fillingability and non-segregation of high flosing concrete according to the volume ratio of coarse aggregate of concrete(G/Glim).

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Bread Properties Utilizing Extracts of Mume (매실(Prumus mume Sieb. et. Zucc)추출물을 이용한 제빵 적성)

  • 이연화;신두호
    • The Korean Journal of Food And Nutrition
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    • v.14 no.4
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    • pp.305-310
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    • 2001
  • In order to study bread properties utilizing extracts of fume, mume bread was baked, adding 0, 0.5, 1.0. 1.5 and 2.0 brix of mume extract to wheat flour. The rheological properties, dough pH, dough volume, bread volume, bread color. bread texture and sensory evaluation were tested to examine bread properties baked adding extracts of mume. The results are as follows: The maximum viscosity measured by amylograph decreased gradually with increasing fume extract concentration, while the gelatinization temperature was going up. The development time measured by farinograph increased with use of mime extract, but stability time decreased. After the first fermentation, dough volume decreased greatly under pH 4.0, and there was same tendency in loaf volume. Lightness and redness of the crumb decreased but yellowness increased. Hardness and fracturability of mume bread were lower than control. In sensory evaluation, fume bread with 0.5 brix muse extract was evaluated as the best in taste, texture, flavor and overall acceptability.

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Effects of Resin Quantity on the Strength Properties of Polyester Resin Concrete (폴리에스터 레진콘크리트에서 수지 사용량에 따른 강도특성)

  • 황광률;소형석;소승영;박홍신;소양섭
    • Proceedings of the Korea Concrete Institute Conference
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    • 1994.10a
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    • pp.235-239
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    • 1994
  • Polymer mortars are mainly used as protective coatings in concrete, reinforced concrete, and more rarely, steel, while polymer concretes represent a new type of structural material capable of withstanding highly corrosive environments. The mechanical properties, chemical stability, and some other useful properties are the reasons research, design, and production organizations. However polymer mortars and polymer concretes have been introduced only recently, and many of their properties are still imperfectly known. And, the main technique in producing polymer concrete is to minimize void volume in the aggregate mass so as to reduce the quantity of the relatively impressive polymer necessary for binding the aggregate. In this study, compressive strength and flexural strength of unsaturated polyester resin concrete are related to quantity of resin and solid volume of aggregate. It was founded that the more solid volume of aggregate increase, the less using quantity of resin decrease with out reducing mechnical properties. When solid volume ratio of aggregate is 70.6%, using quantity of resin is minimized to 10wt.%.

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Study on the unidirectional compaction of terminal cables in the CICC joint

  • 남현일;이호진;박재학;홍계원
    • Progress in Superconductivity
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    • v.3 no.2
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    • pp.218-223
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    • 2002
  • The void volume fraction of cables is one of the effective parameters to characterize the joints of superconducting magnet. Because electrical resistance and cooling stability in the CICC (Cable-in-Conduit Conductors) joint are governed by the void volume fraction, it should be controlled constantly in the termination of cable. The change of cross-section shape in the cable was fecund during the unidirectional compaction of terminal sleeve. The non-uniform thickness of the sleeve after compaction is expected because the loading is not taxi-symmetric, and the plastic flow is also not axi-symmetric. The CICC was compacted from 45% void volume fraction to 15% by using two-piece compaction jig, which could be pressed mini-directionally. Commercial code, ABAQUS, was used to analyze the plastic flow in the sleeve during the unidirectional compaction. The increment of radius of curvature of compaction jig could minimize the change of the deformed shape of cables. The calculated results were agreed with the experimental observations.

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Spatially multiplexed volume hologram using an optical fiber (광섬유를 이용한 위치 다중화 구조의 체적 홀로그램)

  • 강용훈;김기현;이병호
    • Korean Journal of Optics and Photonics
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    • v.8 no.3
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    • pp.241-244
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    • 1997
  • A speckle pattern from an optical fiber is used for a reference beam in writing and reading a volume hologram. The photorefractive volume hologram with this scheme shows good spatial selectivity for spatial(shift) multiplexing because the speckle pattern in writing and reading a hologram looses correlation with a small spatial shift. This scheme has the insensitivity to axial movement. The data storage system with this scheme will have a high storage density and a good stability in operation. We theoretically analyze the diffracted beam from a volume hologram recorded with the speckle pattern from the optical fiber. Experimental results are presented and compared with numerical analysis.

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