• 제목/요약/키워드: addition tests

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폴리프로필렌 섬유보강 콘크리트의 건조수축특성 (Shrinkage Properties of Polypropylene Fiber Reinforced Concrete)

  • 이주형;윤경구;안태송;박제선
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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    • pp.115-118
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    • 1999
  • Tensile behavior of polypropylene fiber reinforced concrete due to restrained shrinkage has been investigated experimentally by ring and beam tests. Parameters include types of concrete, water-cement ratio, volume fraction of fiber and steel ratio. Results show that little influence of the addition of polypropylene(Vf=0.1%) has been observed as expected and results from other researches.

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폴리머재료의 파괴인성치에 관한 연구 (A study on the Dynamic Fracture Toughness for Polymeric Materials)

  • 최영식;박명균
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2001년도 춘계학술대회
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    • pp.311-317
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    • 2001
  • The notched Charpy and Izod impact tests are the most prevalent techniques used to characterize the effects of high impulse loads on ploymeric materials. An analysis method for rubber toughened PVC is suggested to evaluate critical strain energy release rates(Gc) from the Charpy impact energy measurements. An Instrumented Charpy Impact tester was used to extract ancillary information concerning fracture properties in addition to total fracture properties and maximum critical loads. The stress intensity factor Kd was computed for varying amounts of rubber contents from the obtained maximum critical loads and also toughening effects were investigated as well.

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강섬유 보강 RC 기둥의 전단능력 산정 (Shear Capacity Determination of Steel Fiber Reinforced RC Columns)

  • 이현호;장극관
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.891-896
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    • 2001
  • As composite materials, the addition of steel fiber in concrete significantly improves the engineering properties of structural members, notably shear strength and ductility, In this study, shear capacity evaluation method according to steel fiber contents was proposed from the literature surveys and member tests. For this, previously proposed five shear strength equation were examined and evaluated by maximum shear strength and shear capacity ratio. From the parametric study and regression analysis, following conclusion can be made; the maximum shear strength of steel fiber reinforced column will be estimated by relative shear capacity ratio.

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Sensitivity Analysis for Ordered Categorical Data

  • Cho, Il-Hyun;Park, Taesung
    • Communications for Statistical Applications and Methods
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    • 제6권2호
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    • pp.375-382
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    • 1999
  • Linear-by-linear association models are commonly used to analyze ordered categorical data. To fit these models appropriate scores need to be chosen. In this paper we perform sensitivity analyses in two-way contingency tables to investigate the effect of scores on goodness-of-fits and on tests of significance. In addition we show that the best score which yields the best fit of data can be selected based on the sensitivity analysis results.

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고성능 AE감수제를 사용한 콘크리트의 기초적 성질 (Properties of Concrete Using Slump Retentive Superplasticizer)

  • 최재진;김은겸;신치범
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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    • pp.638-644
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    • 1999
  • Workability time of superplasticized concrete is maintained generally for 30-60 minutes only. Therefore it is of great advantage for the concrete producer to use a high range water reducer which provides an extended slump life. Recently slump retentive srperplasticizer has been developed. Concrete mixing tests were done to know slump, setting, air content, bleeding and hardening characteristics of concrete using slump retentive superplasticizer. With slump retentive superplasticizer, high quality concrete was produced and slump loss of concrete was reduced in big way, making long transportation time possible as a practical alternative to on-site addition.

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Discharge characteristics of MgO layer prepared via aqueous solution process

  • Choi, Hak-Nyun;Kim, Yong-Seog
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.379-382
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    • 2006
  • In this study, an attempt was made to form magnesium oxide layer via aqueous solution route of salt precipitation process. A layer with flake morphology was formed from the process and various dopants were added during the forming process. The films formed were characterized using SEM, XRD, and cathodoluminescence measurement. In addition, the discharge characteristics were evaluated using panel tests. The results indicate that MgO film can be formed via the aqueous solution process successfully, of which characteristics are comparable to those of MgO film formed by e-beam evaporation process.

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Goodness-of-fit Test for Rayleigh Distribution

  • Sultan, K.S.
    • International Journal of Reliability and Applications
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    • 제8권1호
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    • pp.41-51
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    • 2007
  • In this paper, we use the moments of order statistics derived by Lieblein (1955) to develop the correlation goodness-of-fit test for the Rayleigh distribution. In such we simulate the percentage points of the test statistics for the one-parameter and two-parameter cases. In addition, we calculate the power of the proposed tests based on some alterative distributions. Finally, we apply the procedures developed in the paper to some real data.

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지오그리드로 보강된 철도노반 쇄석기층의 지지력에 관한 연구 (Bearing Capacity of Geogrid-Reinforced Railroad Ballast)

  • 신은철;김두환;이규진;이상조
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 1999년도 춘계학술대회 논문집
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    • pp.367-374
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    • 1999
  • The selection of geogrid types for the use of reinforced rail roadbed is important in the design of railways. Also, the problem of the construction damage on the geogrid during construction is raised by the field engineers. Therefore, laboratory model tests were peformed to investigate the efficiency of the bearing capacity and construction damage. As a result, it was found that the bearing capacity of the rigid geogrid reinforced railroad ballast shows 1.54 times higher than that of the flexible geogrid reinforced case. In addition, there were no noticeable damage during construction.

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더블앵글 접합부의 극한모멘트 산정을 위한 해석모델 (Analytical Model for the Calculations of Ultimate Moment Capacities of Double Angle Connections)

  • 양재근;이길영;조혜정;천지원
    • 한국공간구조학회:학술대회논문집
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    • 한국공간구조학회 2006년도 춘계 학술발표회 논문집 제3권1호(통권3호)
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    • pp.81-87
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    • 2006
  • This study has been conducted to predict the ultimate moment capacities of double angle connections with various angle thicknesses and bolt gage distances. Considering the results of experimental tests conducted previously, a simplified analytical model is suggested in this research. In addition, some basic data are also provided for structural engineers to design a double angle connection preliminary.

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Integrated diagnostic approach of pediatric neuromuscular disorders

  • Lee, Ha Neul;Lee, Young-Mock
    • Journal of Genetic Medicine
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    • 제15권2호
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    • pp.55-63
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    • 2018
  • Clinical and genetic heterogeneity in association with overlapping spectrum is characteristic in pediatric neuromuscular disorders, which makes confirmative diagnosis difficult and time consuming. Considering evolution of molecular genetic diagnosis and resultant upcoming genetically modifiable therapeutic options, rapid and cost-effective genetic testing should be applied in conjunction with existing diagnostic methods of clinical examinations, laboratory tests, electrophysiologic studies and pathologic studies. Earlier correct diagnosis would enable better clinical management for these patients in addition to new genetic drug options and genetic counseling.