• Title/Summary/Keyword: optimum length

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The Optimum Design for Low Noise Intake System using Robust Design (강건설계를 이용한 흡기계의 저소음화 최적설계)

  • Oh, Jae-Eung;Cha, Kyung-Joon;Chin, Chung-Un;Choe, Ick-Sung;Lee, Jung-Yoon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1654-1660
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    • 2000
  • Recently, the regulations from the government and the concerns of people give rise to the interest in exhaust and intake noise of passenger car as much as other vehicles. In these demands, performance prediction software was developed in the previous study. In this study, Robust design was used for improving the noise reduction capacity of intake system with the performance prediction software. On the basis of the existing design, length and radius of each component that was thought to effect to capacity of intake system was selected. At first factors are arranged by using $L_{18}$ table of orthogonal array and then optimum value can be obtained by $L_{16}$ table of orthogonal array.

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Properities of Freshly Mixed Concrete Using Recycled Coarse Aggregates and Steel Fiber (강섬유를 혼입한 굳지 않은 재생 콘크리트의 특성에 관한 연구)

  • 구봉근;김창운;김태봉;박재성
    • Journal of the Korea Concrete Institute
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    • v.12 no.5
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    • pp.93-99
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    • 2000
  • The physical properties of freshly mixed steel fiber reinforced recycled concrete(SFRRC) were_investigated. Physical state and quality of fresh concrete were monitored batch by batch. the properties of freshly mixed SFRRC were determined in terms of slump, air content, superplasticizer, and bleeding ratio. Concrete mixtures were produced for three kinds of aggregate proportions. So, the experimental variables are various aggregate proportions, steel fiber contents(0, 0.5, 1.0, 1.5%) and steel length(30, 50, 60mm). From experimental results, optimum s/a by various experimental variables, variations of the slump by the air contents, and optimum superplasticizer to decrease unit water were presented.

A Study of the Convective Heat Transfer in a Vertical Channel of an Array of Heated Protrusions (수직 채널내의 가열 돌출 배열에서의 대류 열전달)

  • B. J, Baek
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.6
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    • pp.844-853
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    • 1998
  • Natural and forced convection experiments were carried out in order to investigate the effects of channel spacing gap between protrusions and number of rows of protrusion, In natural convection the optimum channel spacing was found to be approximately 20mm regardless of the protrusion gaps. For optimum channel spacing the heat transfer coefficients were converged to an asymptotic value after the fourth row. The heat transfer coefficient for each row approaches to constant values for protrusion gaps larger than 10 mm. An experimental correlation has been suggested by using a modified Rayleigh number based on the dimensionless characteristic length(G/L). In forced convec-tion the heat transfer coefficients were not merged to an asymptote until the fifty row and increases as the channel spacing at the constant Reynolds number decreases.

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Tetra Primer ARMS PCR Optimization to Detect Single Nucleotide Polymorphisms of the CYP2E1 Gene

  • Suhda, Saihas;Paramita, Dewi Kartikawati;Fachiroh, Jajah
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.7
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    • pp.3065-3069
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    • 2016
  • Single nucleotide polymorphism (SNP) detection has been used extensively for genetic association studies of diseases including cancer. For mass, yet accurate and more economic SNP detection we have optimized tetra primer amplification refractory mutation system polymerase chain reaction (ARMS PCR) to detect three SNPs in the cytochrome P450 2E1 (CYP2E1) gene locus; i.e. rs3813865, rs2070672 and rs3813867. The optimization system strategies used were (1) designing inner and outer primers; (2) determining of their optimum primer concentration ratios; and (3) determining of the optimum PCR annealing temperature. The tetra primer ARMS PCR result could be directly observed using agarose gel electrophoresis. The method succesfully determined three SNPs in CYP2E1 locus, the results being consistent with validation using DNA sequencing and restriction fragment length polymorphisms (RFLP).

Optimization of edger model to increase rolling yields in the plate mill (Edger 압연모델 최적화를 통한 후판압연 실수율 개선)

  • 천명식;이준정;문영훈
    • Transactions of Materials Processing
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    • v.8 no.2
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    • pp.208-215
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    • 1999
  • To increase rolling yields by minimizing trimming losses of hot-rolled plate, optimization logic for the edger model has been developed. The logic to determine optimum edging amount model has been formulated on the basis of actual production rolling data. In case of broadside rolling, the fish tail shape at the sides of plate was better for reducing the crop loss and this could be achieved when the edging amount of broadside rolling was increased. At a given broadside rolling ratio, methodology to determine optimum edging amount for the finish rolling which could minimize the width deviation of plate were systematically derived. Therefore, for a given broadside rolling condition and the permissible tolerance in width deviation of plate, it was possible to optimize the edging amount in finish rolling to maximize rolling yields. The application of optimization logic in this study increased rolling yields from approximately 10% to 30% at various longitudinal eding raitos.

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A Study on Optimum Lighting Conditions for Effective Coordnate Measuring Machine (효율적인 CMM을 위한 조명 조건 개선에 관한 연구)

  • Bae, Jun-Young;Ban, Kap-Soo
    • Journal of the Korean Society of Industry Convergence
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    • v.17 no.3
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    • pp.184-193
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    • 2014
  • Machine vision systems is applied for various industries such as optimize your spending, automate your production and maximize your efficiency. This research is effective for most optimal light condition of machine vision that technology was applied bald outside human visual acuity. Image processing converts a target image captured by a CCD camera into a digital signal and then performs various arithmetic operations on the signal to extract the characteristics of the target, such as points, lines, circles, area and length. The mathematical concepts of convolution and the kernel matrix are used to apply filters to signals, to perform functions such as extracting edges and reducing unwanted noise. This research analyze and compares matching ratio with reference image and search for optimal lighting condition in accuracy that user wants coming input image according to brightness change of lighting.

계면활성제를 이용한 우지지방산을 포화지방산과 불포화 지방산의 분리

  • 이옥섭;김점식
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.10 no.1
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    • pp.24-41
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    • 1984
  • Tallow fatty acid consists of mixtures of fatty acids differing in chain length and saturation. In separation of tallow fatty acid, the effects of the type and concentration of detergents and electrolytes were studied. And the changes of acid composition of particular fractions were determined by gas-chromatography. Sodium lauryl sulfate (SLS), sodium lauryl ether sulfate (SLES) and sodium lauryl benzene sulfonate (SLBS) were used as detergents and NaCl, Na2SO4 and MgSO4 were used as electrolytes. At low concentration of detergent, the tallow fatty acid was not fully wetted, and at high concentration, the emulsion was so stable that the tallow fatty acid was not well separated. The addition of proper amount of electrolyte increased the separation efficiency by the decrease of interfacial tension and by the increase of the amount of adsorbed detergent on the surface of solid fatty acid crystals. The optimum range of detergent was 0.4-0.6% (wt.) in SLS, 0.2-0.4% in SLES and 2.0-) .0% in SLBS. And the optimum range of electrolyte was 2.0-2.5% in NaCl, 3.0-4.0% In Na2SO4 and 0.5-1.0% in MgSO4 respectively.

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Studies on the Optimum Light Intensity for Growth of Panu ginseng (II) Study on the difference of the optimum light intensity for the growth of ginseng Plant accordingto the root age (인삼생육의 최적광량에 관한 연구 (제2보) 인삼생육에 대한 최적광량의 년생간 차이에 관하여)

  • 이종철;천성기
    • Journal of Ginseng Research
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    • v.6 no.2
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    • pp.149-153
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    • 1982
  • To investigate the effect of light intensity on the growth of shoots and roots, water and chlorophyll contents in the ginseng leaf were determined at 5%, l0%, 20%, 30% light transmittance rate (LTR) with 1,2 and 4 year-old ginseng plants in the field. Stem length, size of the leaf, water and chlorophyll contents were decreased as the increase of the light intensity in all ages of ginseng plants. The degree of decrease was severe in the one year-old ginseng compared to that of 2, or 4 year-old ginseng, while there was no difference between the 2 and 4 year-old plants. Root weight per plant was highest at 5% LTR in the one year-old plants, while it was at 20% LTR in the 2 and 4 year-old plants. Generally, demand of light for the growth of one year-old ginseng was lower than those of 2 or 4 year-old plants there was no difference of it among the ginseng plants older than 2 years.

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A Theoretical Study on a Folding Shading Device (접이식 차양장치에 관한 이론적 연구)

  • Baek, Sang-Hun;Choi, Won-Ki;Suh, Seung-Jik
    • Journal of the Korean Solar Energy Society
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    • v.29 no.3
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    • pp.28-36
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    • 2009
  • The majority of fixed shading devices are installed in the exterior of a building in order to dissipate the heat absorbing from the sun and to prevent the direct sunlight. In designing external shading devices for windows, many requirements must be considered simultaneously; solar geometry, optimum energy performance, multi-purpose usage and design factors etc.. In order Lo satisfy these requirements, we suggests the folding shading device and its optimum design methodology. Also we analyzed the thermal performance using the IES_VE program according to various operating modes and compared with existing shading devices. The results show that proposed device reduce about $1.90{\sim}22.40%$ in cooling load and about $1.09{\sim}24.22%$ in heating load in comparison with existing ones.

Design and Simulation of Heating Rubber Roller for Laminating Process

  • Hur, Shin;Woo, Chang Su
    • Elastomers and Composites
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    • v.51 no.4
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    • pp.280-285
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    • 2016
  • The purpose of this study is to get optimum design and operation conditions of the heating rubber roller for laminating process. The cause of performance degradation of heating rubber roller is delamination of rubber on metal tube, rubber aging due to high temperature. We measured the material properties of thermal expansion, thermal conductivity, specific heat and density and analyzed thermal distributions of rubber layer using finite element method. As a result of heat/flow analysis, the density distribution of heating coil must shorten the stabilization time by reducing the temperature deviation on the length direction at the temperature rising section after increasing the density of the area contacting with the laminate film at the center part which is an opposite of the current composition while enabling to maintain the temperature of heater to be consistent while maintaining the temperature deviation to be low when heat loss is created. Finally, we determined optimum heating method of heating rubber roller.