• Title/Summary/Keyword: Permeability Factors

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The Effect of Paper Permeability on Cigarette Properties (종이의 투기도가 담배 물성에 미치는 영향)

  • 김영호;한영림;이문용;이영택;김정열
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.33 no.1
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    • pp.64-72
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    • 2001
  • The cigarette ventilation affects not only the amount of tar and nicotine delivery by a cigarette, but also the composition of the smoke. Therefore, it is important to stabilize of variability in cigarette ventilation that would be affected by changes in cigarette components. This work was conducted to determine the major factors that influence the cigarette ventilation and also to provide fundamental informations for improving the uniformity of cigarette performances. To evaluate the effect of cigarette ventilation as a dependant variable, the three independent factors were the air permeability of plugwrap, tipping paper and the filter pressure drop. We determined the effect of paper permeability on ventilation variability and the optimum condition in combinations of independent factors. The mean of cigarette ventilation was increased as plugwrap permeability increases, particularly at 26,000 CU. However, it was exhibited that standard deviation and coefficient of variation of the cigarette ventilation were decreased with increasing plugwrap permeability. At the 600 CU and 1,200 CU of tipping paper permeability, process capability index (Cp) of the cigarette ventilation increased as plugwrap permeability increases. Following the optimum condition of cigarette ventilation induced by fitted regression equation, one was to optimize 50% ventilation level is by combination with plugwrap permeability of 16,000 CU, tipping paper permeability of 810 CU, filter pressure drop of 319 mm$H_2O$, respectively.

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Estimation model of coefficient of permeability of soil layer using linear regression analysis (단순회귀분석에 의한 토층지반의 투수계수 산정모델)

  • Lee, Moon-Se;Kim, Kyeong-Su
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.1043-1052
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    • 2009
  • To derive easily the coefficient of permeability from several other soil properties, the estimation model of coefficient of permeability was proposed using linear regression analysis. The coefficient of permeability is one of the major factors to evaluate the soil characteristics. The study area is located in Kangwon-do Pyeongchang-gun Jinbu-Myeon. Soil samples of 45 spots were taken from the study area and various soil tests were carried out in laboratory. After selecting the soil factor influenced by the coefficient of permeability through the correlation analysis, the estimation model of coefficient of permeability was developed using the linear regression analysis between the selected soil factor and the coefficient of permeability from permeability test. Also, the estimation model of coefficient of permeability was compared with the results from permeability test and empirical equation, and the suitability of proposed model was proved. As the result of correlation analysis between various soil factors and the coefficient of permeability using SPSS(statistical package for the social sciences), the largest influence factor of coefficient of permeability were the effective grain size, porosity and dry unit weight. The coefficient of permeability calculated from the proposed model was similar to that resulted from permeability test. Therefore, the proposed model can be used in case of estimating the coefficient of permeability at the same soil condition like study area.

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Permeability Characteristics of Sedimented Clayey Soils (점토퇴적지반의 투수특성 연구)

  • Kim Dae-Kyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.6 no.1
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    • pp.72-77
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    • 2005
  • The oedometer test and the constant rate of consolidtion test were performed using the sedimented clayey soil sample. The characteristics of permeability of the clayey soil such as anisotropy, permeability change index, relation with void ratio, and influencing factors, were investigated from the lab. test results. Analyzing the permeability characteristics, the representative permeability coefficient was proposed.

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Circulating Permeability Factors in Idiopathic Nephrotic Syndrome

  • Ha, Tae-Sun
    • Childhood Kidney Diseases
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    • v.23 no.1
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    • pp.7-21
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    • 2019
  • Nephrotic syndrome (NS) is a common chronic glomerular disease in children characterized by significant proteinuria with resulting hypoalbuminemia, edema, and hyperlipidemia. Renal biopsy findings of diffuse foot processes effacement on electron microscopy and minimal change disease, focal segmental glomerulosclerosis (FSGS), or diffuse mesangial proliferation on light microscopy. It has been speculated that circulating permeability factors would be implicated in the pathogenesis of NS because they have been reportedly detected in the sera of patients and in experimental models of induced proteinuria. Moreover, a substantial portion of the patients with primary FSGS recurrence shortly after transplantation. This report reviews the current knowledge regarding the role of circulating permeability factors in the pathogenesis of proteinuria in NS and suggests future targeted therapeutic approaches for NS.

River Embankment Integrity Evaluation using Numerical Analysis (수치해석을 이용한 하천제방의 건전도 평가)

  • Byun, Yo-Seph;Jung, Hyuk-Sang;Kim, Jin-Man;Choi, Bong-Hyuck;Kim, Kyung-Min;Chun, Byung-Sik
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.524-528
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    • 2009
  • An influence factors for soundness evaluation of river levee include resistibility and embankment for piping of ground consisting embankment in case piping, permeability coefficient of ground, height of embankment, the width of crest, material characteristics of embankment and foundation ground, shape of embankment slope, an influence for penetration of rainfall or river water in case slope stability. In this study, it was operated a feasibility investigation of existing design result, stability evaluation for permeability coefficient use and permeability coefficient change of foundation ground to investigate an influence in line with permeability coefficient change for result of river levee penetration analysis. The evaluation results of influence factors, the permeability coefficient used in design and it was evaluated influence in safety factor of piping. After the evaluation of influence factors, the permeability coefficient used in the design appears with the fact that differs in a design report about same soil, Accordingly, the stability investigation of embankment by application of literature data can affect stability evaluation results by change factors like a permeability coefficient, void ratio. It should be certainly used material properties by a test in soundness evaluation of river levee.

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The Effect of Paper Permeability on Cigarette Properties (종이의 투기도가 담배 물성에 미치는 영향)

  • Young-Hoh Kim;Young-Rim Han;Moon-Yang Lee;Young- Taek Lee;Chung-Ryul Kim
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.33 no.1
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    • pp.62-62
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    • 2001
  • The cigarette ventilation affects not only the amount of tar and nicotine delivery by a cigarette, but also the composition of the smoke. Therefore, it is important to stabilize of variability in cigarette ventilation that would be affected by changes in cigarette components. This work was conducted to determine the major factors that influence the cigarette ventilation and also to provide fundamental informations for improving the uniformity of cigarette performances. To evaluate the effect of cigarette ventilation as a dependant variable, the three independent factors were the air permeability of plugwrap, tipping paper and the filter pressure drop. We determined the effect of paper permeability on ventilation variability and the optimum condition in combinations of independent factors. The mean of cigarette ventilation was increased as plugwrap permeability increases, particularly at 26,000 CU. However, it was exhibited that standard deviation and coefficient of variation of the cigarette ventilation were decreased with increasing plugwrap permeability. At the 600 CU and 1,200 CU of tipping paper permeability, process capability index (Cp) of the cigarette ventilation increased as plugwrap permeability increases. Following the optimum condition of cigarette ventilation induced by fitted regression equation, one was to optimize 50% ventilation level is by combination with plugwrap permeability of 16,000 CU, tipping paper permeability of 810 CU, filter pressure drop of 319 mm$H_2O$, respectively.

A Study on measuring the Initial Permeability of Magnetic Powder considered Demagnetizing factors (반자장계수를 고려한 자성분말의 초투자율 측정에 관한 연구)

  • Jun, Hong-Bae;Heo, Jin;Kim, Chul-Han;SaGong, Geon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.05b
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    • pp.86-90
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    • 2000
  • In this study, A equipment for measuring the initial permeability of soft-ferrite powder was developed by using a differential transformer coil, and was investigated demagnetizing factors. To measure the initial permeability of magnetic ceramic powder is cumbersome since there are not any measuring equipment and method. Magnetic powder is currently used for a magnetic fluid and microwave absorber materials, and the initial permeability of the magnetic powder is very important to be evaluated a powder for some applications.

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Numerical Analysis for Integrity Evaluation of River Bank (하천제방의 건전도 평가를 위한 수치해석적 연구)

  • Jung, Hyuksang;Byun, Yoseph;Chun, Byungsik;Choi, Bonghyuck;Kim, Jinman
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.11
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    • pp.19-26
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    • 2010
  • An influence factors for soundness evaluation of river levee include consisting embankment in case piping, permeability coefficient of ground, height of embankment, the width of crest, material characteristics of embankment and foundation ground, shape of embankment slope, an influence for penetration of rainfall or river water in case slope stability. In this study, it was operated a feasibility investigation of existing design result, stability evaluation for permeability coefficient use and permeability coefficient change of foundation ground to investigate an influence in line with permeability coefficient change for result of river levee penetration analysis. The evaluation results of influence factors, the permeability coefficient was used in design and it was evaluated influence in safety factor of piping. After the evaluation of influence factors, the permeability coefficient used in the design appears with the fact that differs in a design report about same soil.

Effect of Fabric Structural Parameters and Surface Finishing Characteristics to Water Repellency/Proofing/Vapor Permeability of Breathable Fabrics for Sportswear Clothing (직물 구조인자와 표면 가공특성이 스포츠 의류용 투습직물의 발수/방수/투습특성에 미치는 영향)

  • Kim, Hyun Ah
    • Fashion & Textile Research Journal
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    • v.22 no.1
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    • pp.112-118
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    • 2020
  • This paper examined the water repellency, water proofing and water vapor permeability of twelve types of woven fabrics for sports wear clothing. Their physical properties were compared and discussed with the fabric structural parameters and surface finishing effect. A water repellent property of 100% was obtained in the coated or laminated water repellent finished fabrics; in addition, cotton/nylon breathable composite fabrics treated with a laminated finishing and with low fabric density showed a 90% water repellency. Water proofing fabric above 6,000 mm H2O hydraulic pressure was achieved by coated or laminated finishing; however, high density fabric or medium-level coated fabrics exhibited 100% water repellent and low water proofing characteristics. Superior water vapor permeability characteristics with good water repellency and proofing properties were achieved at the 2.5 layered low density and with 0.7 - 0.9 cover factor nylon fabrics treated with hydrophilic laminated finishing. The regression analysis for examining the effects of fabric structural parameters and surface finishing such as coating and laminating to the water vapor permeability exhibited a high determination coefficient of fabric structural parameters of 63.5%; in addition,, main factors among fabric structural parameters appeared to be cover factor and fabric thickness per weight. Coating and Laminating factors exhibited determination coefficient of water vapor permeability parameters of 36.5%.

Correlation Among Permeability, Apparent Density, And Porosity of Human Lumbar Vertebral Trabecular Bone (인체 요추해면골의 배류계수, 겉보기밀도, 공극비 사이의 상관관계에 관한 연구)

  • 홍정화;강신일
    • Journal of Biomedical Engineering Research
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    • v.18 no.4
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    • pp.333-338
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    • 1997
  • Abnormal intraosseous flow and pressure in trabecular bone could cause various pathological conditions such as osteonecrosis and osteoarthritis. Characteristics of intraosseous fluid flow and pressure generation in porous trabecular bone can be significantly affected by the permeability. Factors which determine the permeability could be the porosity and apparent density of trabecular bone. However, there is little data on the permeability and the relationship among the permeability. porosity, and apparent density of trabecular bone. In this study. the permeability. porosity, and apparent density of human lumbar vertebral trabecular bone were experimentally measured. Also, a power relationship among the permeability, porosity, and apparent density was investigated to understand effects of the porosity and apparent density variations on the permeability of trabecular bone based on Kozeny-Carman equation. A near linear relationship between intraosseous fluid flow and time indicated that the fluid phase flowed through the pores in trabecular bone is governed by the permeability. The permeability of trybecular bone was found to have a significant power relationship with the porosity and apparent density (r: 0.84 and $\textit{p}$< 0.0005). The power relationship could be useful to determine the permeability of trybecular bone after measuring the apparent density and porosity.

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