• Title/Summary/Keyword: yield conditions

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A critical review on blood flow in large arteries; relevance to blood rheology, viscosity models, and physiologic conditions

  • Yilmaz, Fuat;Gundogdu, Mehmet Yasar
    • Korea-Australia Rheology Journal
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    • v.20 no.4
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    • pp.197-211
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    • 2008
  • The purpose of this study is mainly directed towards present of viewpoints on critical and commentary analysis on blood rheology, blood viscosity models, and physiological flow conditions. Understanding these basics is fundamental to meet the need for a sufficient and reliable CFD model of blood. Most of the used viscosity models on this manner have determined from parameter fitting on experimental viscosity data. Availability of experimental data from literature to define viscosity models of CFD analysis should be accurately chosen and treated in order to avoid any errors. Several basic gaps that limit the CFD model results are identified and given opportunities for future research.

Study of Rice Husk Pulping for utilization of Rice Husk Fiber (왕겨섬유 활용을 위한 왕겨 펄프화 연구)

  • Oh, Min-Taek;Sun, Yong-Joo
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.44 no.3
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    • pp.63-69
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    • 2012
  • The rice husk is one of the major agricultural residue in KOREA. In this paper, the effects of various pulping conditions on the properties of rice husk pulp and handsheets made of rice husk fiber were evaluated in order to utilize the rice husk as an alternative source for wood pulp. Two typical alkali pulping, such as soda pulping and Kraft pulping were applied with various conditions of the pulping processes. The higher effective alkali and higher pulping temperature resulted in the higher efficiency in removal of lignin and ash, which leaded to the higher strength properties of handsheets made of rice husk fiber, but the lower yield of rice husk pulp. The better efficiency in production of rice husk pulp and the stronger handsheets were obtained by the Kraft pulping.

Structural Analysis of Booms and Basket in the Multi-aerial Platform (복합 굴절차의 붐과 바스켓에 대한 구조 해석)

  • So, Soo-Hyun;Kang, Sung-Soo
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.6
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    • pp.885-891
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    • 2012
  • In this study, some structural analysis using 3D CAD data, material properties, load conditions and boundary conditions are carried out to evaluate structural stability of the multi-aerial platform for high-rise fire fighting and rescue. We conduct structural analysis for the upper structures such as turn table, booms and basket, by using a universal structural analysis program NASTRAN. As the results, there is local stress exceeding the yield strength, but it is able to relax stress concentration in a way such as changing thickness of the structure or making larger inertia moment in cross section of booms.

Theoretical Considerations on an Electrolytic Reduction Process for Reducing Spent Oxide Fuel

  • Park B. H.;Seo C. S.;Jung K.-J.;Park S. W.
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2005.11b
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    • pp.86-91
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    • 2005
  • A metal product obtained from an electrolytic reduction process, possesses less volume and radioactivity than those of the unprocessed spent oxide fuels. The chemical composition of the metal product varies according to the process condition. In this work, a basic study was performed to evaluate the chemical forms of the spent oxide fuel components in an electrolytic reduction process with the operation conditions. One of the most important operation conditions is the cell potential applied for the reduction cell. It is expected that $PU_{2}O_3$ is difficult to reduce even though the cell potential is negative enough to reduce the lithium oxide when the activity of $Li_{2}O$ exceeds 0.003. The reduction of actinide oxides via the reduction of $Li_{2}O$ is assumed to have a greater reduction yield than a direct reduction of the actinide oxides.

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Effect of Boundary Conditions of Failure Pressure Models on Reliability Estimation of Buried Pipelines

  • Lee, Ouk-Sub;Pyun, Jang-Sik;Kim, Dong-Hyeok
    • International Journal of Precision Engineering and Manufacturing
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    • v.4 no.6
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    • pp.12-19
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    • 2003
  • This paper presents the effect of boundary conditions in various failure pressure models published for the estimation of failure pressure. Furthermore, this approach is extended to the failure prediction with the aid of a failure probability model. The first order Taylor series expansion of the limit state function is used in order to estimate the probability of failure associated with each corrosion defect in buried pipelines for long exposure period with unit of years. A failure probability model based on the von-Mises failure criterion is adapted. The log-normal and standard normal probability functions for varying random variables are adapted. The effects of random variables such as defect depth, pipe diameter, defect length, fluid pressure, corrosion rate, material yield stress, material ultimate tensile strength and pipe thickness on the failure probability of the buried pipelines are systematically investigated for the corrosion pipeline by using an adapted failure probability model and varying failure pressure model.

Studies on Setting up of Radioimmunoassay System of Thyroid Stimulating Hormone (갑상선자극(甲狀腺刺戟)호르몬의 방사면역측정법(放射免疫測定法) 확립(確立)에 관한 연구(硏究))

  • Kim, Jae-Rok;Park, Kyung-Bae;Awh, Ok-Doo
    • The Korean Journal of Nuclear Medicine
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    • v.20 no.1
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    • pp.75-83
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    • 1986
  • Various TSH RIA kit components were prepared. Conditions for $^{125}I$ labelling of h-TSH were optimized by diminishing the amount of chloramine-T, ertending reaction time and lowering reaction temperature. Yield, specific activity, and immunological activity could be maintained moderately under such mild reaction conditions. The mixture of polyethyleneglycol(PEG) and second antibody worked effectively as a B/F separation agent. Even though the mixture was made with more diluted PEG and second antibody than those of using the sole component separately, the tine required for the B/F separation was shorter in case of using the mixture. The sequential saturation technique was efficient than those of applying ordinary equilibrium saturation technique in assay sensitivity and assay precision points of view.

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Study of Dyeing Properties by Swelling Agent on meta-aramid Fiber with Cationic Dyes (Swelling agent에 따른 메타계 아라미드 섬유의 Cationic dye 염색특성)

  • Kim, Eun-Mi;Park, Chung-Won;Choi, Jae-Hong
    • Textile Coloration and Finishing
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    • v.24 no.1
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    • pp.1-7
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    • 2012
  • Dyeing and fastness characteristics of 100% meta-aramid fiber were investigated with cationic dyes and swelling agents under various dyeing conditions such as dyeing temperature and pH of dye bath. Dye exhaustion started at around $80^{\circ}C$ and settled down at $130^{\circ}C$. Among swelling agents used, N-methyl formanilide showed comparatively higher K/S values comparing to 1-phenoxypropan-2-ol. Under weak acidic conditions in the range pH 5 to 7, the exhaustion of cationic dyes could be enhanced leading to higher adsorption and stability of colorimetric property. Wash and rubbing fastness were generally good but low light fastness found can be attributable to the poor photo-stability of the cationic dyes.

Studies on the Optical Resolution of DL-Amino Acids by Aminoacylase Immobilized on Chitosan: Immobilization of Aminoacylase (Chitosan 고정화 Aminoacylase를 이용한 DL-아미노산의 광학적 분할에 관한 연구 : Aminoacylase 의 고정화)

  • Lee, Sang-Hyun;Lee, Young-Chun
    • Korean Journal of Food Science and Technology
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    • v.20 no.4
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    • pp.541-546
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    • 1988
  • Optimum conditions for immobilization of aminoacylase on chitosan were investigated, and the results are summerized as follows: Optimum conditions for activation of chitosan were pH 6.0, 0.2% of glutaraldehyde, and 120 minutes of reaction time. Enzyme concentration and reaction time for immobilization of aminoacylase on the activated chitosan were 80mg/20ml, and 90 minutes, respectively, and the yield of activity of the immobilized enzyme was 42.6%.

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The characterization of AlN thin films grown on GaAs(100) substrate (GaAs(100) 기판위에 성장된 AIN 박막의 특성)

  • 정성훈;김영호;송복식;문동찬;김선태
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.11a
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    • pp.33-36
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    • 1996
  • AIN thin films were prepared using by Rf sputtering method on the GaAs(170) substrate and investigated by X-ray diffractometer, IR spectroscopy, n&k system. The parameters were the substrate temperature, RF power, sputtering duration and the $N_2$/Ar ratio. The AlN thin films of (101) orientation were obtained under the conditions of room temperature and the nitrogen of 60 vol.%. The crystallinity of the films, which were grown respectively under the different conditions, were determined by the comparison of the band width of an E$_1$[TO:680$cm^{-1}$ /] phonon mode. The thicknesses of AlN films were decreased dramatically in the region of the nitrogen of 40~60 vol.% according to the increment of the $N_2$/Ar ratio by which the sputter yield got lower.

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Stress-Path Dependent Behavior of Granular Soil (입상토의 응력경로 의존거동)

  • 정진섭;권원식
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.40 no.1
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    • pp.106-117
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    • 1998
  • The nature of stress-path dependency, the principle that governs deformations in granular soil, and the use of Lade's double work-hardening model for predicting soil response for a variety of stress-paths have been investigated, and are examined The test results and the analyses presented show that under some conditions granular soils exhibit stress-path dependent behavior. For stress-paths involving unloading or reloading, the stress-path with the higher average stress level produces the larger strains, whereas all stress-paths having the same intial states of stress, and involving only primary loading conditions, produce strains of similar magnitudes. Experimental evidence indicates that the stress- path dependent response obtained from the double work-hardening model is also observed for real soils. It is concluded that the influence of stress history on the friction angle is negligible and the strains increment direction is uniquely determined from the state of stress but is not perpendicular to the yield surface. The strains calculated from Lade's double work-hardening model are in reasonable agreement with those measured.

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