• 제목/요약/키워드: test scale

검색결과 9,598건 처리시간 0.035초

FRP복합체로 보강된 실물모형 RC보의 보강재 강성에 따른 휨 보강성능 (Flexural Performance of Full-scale RC Beams Strengthened with Different Amount of FRP Composite)

  • 최기선;유영찬;김긍환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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    • pp.125-128
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    • 2006
  • Many research have been carried out concerned with the flexural performance of FRP composite in a various ways. Most of them, however, have used a small-scale specimen, so haven't been fully verified by full-scale model test. In this study, a full-scale RC beam model test for flexural strengthening with CFRP composites has been performed in order to verify test results obtained through a series of small-scale model test with respect to FRP stiffness affecting strengthening performance in the previous studies. A total of 4 specimens have been manufactured including control beam. The specimens strengthened with CFRP composites consist of 3 different CFRP stiffness with 2 types of CFRP composite. Consequently, the purpose of this study is to estimate influence of the size effect of specimens and FRP stiffness on the flexural performance. As a result, the effective strain of FRP composite is inversely proportional to FRP stiffness and ensures the same performance with small-scale model test.

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The Limit Distribution of a Modified W-Test Statistic for Exponentiality

  • Kim, Namhyun
    • Communications for Statistical Applications and Methods
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    • 제8권2호
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    • pp.473-481
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    • 2001
  • Shapiro and Wilk (1972) developed a test for exponentiality with origin and scale unknown. The procedure consists of comparing the generalized least squares estimate of scale with the estimate of scale given by the sample variance. However the test statistic is inconsistent. Kim(2001) proposed a modified Shapiro-Wilk's test statistic based on the ratio of tow asymptotically efficient estimates of scale. In this paper, we study the asymptotic behavior of the statistic using the approximation of the quantile process by a sequence of Brownian bridges and represent the limit null distribution as an integral of a Brownian bridge.

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나노 인장시험을 위한 압축 시험기용 인장시편 제작에 관한 연구 (Fabrication of Nano-Size Specimens for Tensile Test Employing Nano-Indentation Device)

  • 임태우;양동열
    • 한국정밀공학회지
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    • 제32권10호
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    • pp.911-916
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    • 2015
  • In the nano/micro scale, material properties are dependent on the size-scale of a structure. However, conventional micro-scale tensile tests have limitations to obtain reliable values of nano-scale material properties owing to residual stress and elastic slippage in the gripping/aligning process. The indenter-driven nano-scale tensile test provides prominent advantages simple testing device, high-quality nano-scale metallic specimen with negligible residual stress. In this paper, two-types of specimens (a specimen with multi-testing parts and a specimen with a single-testing part) are discussed. Focused ion beam (FIB) is employed to fabricate a nano-scale specimen from a thin nickel film. Using the specimen with a single-testing part, we obtained a nano-scale stress-strain curve of electroplated nickel film.

The Detection and Testing of Multiple Outliers in Linear Regression

  • Park, Jin-Pyo;Zamar, Ruben H.
    • Journal of the Korean Data and Information Science Society
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    • 제15권4호
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    • pp.921-934
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    • 2004
  • We consider the problem of identifying and testing outliers in linear regression. First, we consider the scale-ratio tests for testing the null hypothesis of no outliers. A test based on the ratio of two residual scale estimates is proposed. We show the asymptotic distribution of test statistics and investigate the properties of the test. Next we consider the problem of identifying the outliers. A forward procedure based on the suggested test is proposed and shown to perform fairly well. The forward procedure is unaffected by masking and swamping effects because the test statistics used a robust scale estimate.

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자기 검색척도(Self-Monitoring Scale)의 타당성 검정에 관한 연구 (The Study of the Validity Test on the Self-monitoring Scale)

  • 이선아
    • 대한간호학회지
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    • 제28권3호
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    • pp.751-759
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    • 1998
  • The study of the validity test on the self-monitoring scale for nurses In this study, both the literary survey as well as empirical research has been executed to test the validity of the scales that measure the construct of the self-monitoring scale. The self-monitoring scale could not be classified into five factors as Snyder suggested. Many other scholars (Briggs, Cheek and Buss, 1980) suggested 3 different classifications which was accepted by Snyder and Gangestad (1986). John, Cheek and Klohnen(1996) claimed a two-factor classification. As has been discussed, factor analysis is used to prove convergent validity within the factor and discriminant validity between the factors. However, depending on the researchers, many variations in classification of the factors were found and a lack of content and discriminant validity were found in the previous research findings. It is also important to note that Snyder's self-monitoring scale did not factor-load at over. 30 for all 25 items, regardless of how many factors could be classified. According to findings of this study, the self-monitoring scale neither classified as five, three or two factors nor factor loaded as hypothesized. It is also clear that Snyder's self-monitoring scale lacks convergent validity as the sub-factors of the scale failed to prove its uni-dimensionality. The A self-monit oring scale not only fail to overcome the problems of Snyder's self-monitori ng scale but even lost the attractiveness of the self-monitoring scale. In this study it was also found that the A self-monitoring scale was not classified in either in a two or three-factor classification as hypothesized. It is, of course, not desirable to use any scale that lacks convergent and discriminant validity even though it has been widely used and has held a great deal of influence on the field of social psychology. To overcome the shortcomings of Snyder's self-monitoring scale, Lennox and Wolfe(1984) suggested 13 items. This study was dedicated to test the validity and reliability of the scale, in which we found that the data presented in validity as the two factors were class ified and loaded as expected. Reliability was also proven by checking Cronbach's α for each factor and for the total items. In addition, a confirmatory factor analysis was executed for the 13 items using LISREL 8.12 program to confirm convergent validity in a two-factor classification. The model was fitting and sound : however, the self-monitoring scale was unfitted and not validated. Thus, it is recommended to use not the original nor the abbreviated self-monitoring scale but the 13 items in future studies. It should also be noted that items 7 and 13 should be removed to obtain better uni-dimensionality for the 13 items. These items loaded at over. 30, too high for the two factors in the test results of Factor analysis. In addition, it is necessary to double-check the cause of two-hold loading at over .30 for the two factors. It could be a problem caused by data or by the scale itself. Therefore, additional studies should follow to better clarify this matter.

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1/10 축소 철근콘크리트보의 휨 거동에관한 실험적 연구 (An Experimental Study on the Flexural Behavior of 1/10-Scale Reinforced Concrete Beams)

  • 이한선;장신혁;김상규
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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    • pp.325-330
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    • 1995
  • Three types of model concrete with different mix ratios for 1/10 scale reinforced concrete model were made and tested to find the best solution for the simulation of mechanical characteristics of prototype concrete. Scaled reinforcing materials in diameter(D1.8) having similar con-figuration and mechanical properties with commercial deformed bars(D19) were prepared for 1/10 scale model tests of reinforced concrete structures. Two types of model test using D1.8 model reinforcing bars and model concrete, monotonic simple beam test and cyclic cantilever beam test, were performed to ensure and check the similitude of bond behavior between 1/10 scale model and prototype. The test results showed that the flexural behavior of 1/10 scale models can be simulated with accuracy enough for practical use in monotonic and cyclic loading test.

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Experimental and analytical behaviour of composite slabs

  • Lopes, Emanuel;Simoes, Rui
    • Steel and Composite Structures
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    • 제8권5호
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    • pp.361-388
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    • 2008
  • The Eurocode 4 presents some negative aspects in the design of composite slabs by the m-k Method or the Partial Connection Method. On one hand, the component chemical adherence is not accounted for in the connection between the profiled steel sheet and the concrete. On the other hand, the application of these methods requires some fitting parameters that must be determined by full scale tests. In this paper, the Eurocode 4 methods are compared with a method developed at the Federal Polytechnic School of Lausanne, based on pullout tests, which can be a valid alternative. Hence, in order to calculate the necessary parameters for the three methods, several tests have been performed such as the full scale test described in Eurocode 4 and pull-out tests. This last type of tests is of small dimensions and implicates lower costs. Finally, a full-scale test of a steel-concrete composite slab with a generic loading is presented, with the goal of verifying the analytical formulation.

Reliability and Validity of Korean-Version of Information Needs in Cardiac Rehabilitation Scale

  • Choi, Sang Young Heon;Kim, Joong Hwi
    • The Journal of Korean Physical Therapy
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    • 제34권5호
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    • pp.234-241
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    • 2022
  • Purpose: The Cardiac Rehabilitation scale (INCR scale) is a verified measure worldwide. The scale measures the extent to which cardiac rehabilitation meets the various needs of the participating patients and determines how education related to heart disease and rehabilitation satisfies their preferences. The current study applied the INCR scale to verify and develop it for use in Korea by conforming to Korean culture and language. Methods: The Korean version of the INCR scale was created after a six-step process in accordance with the international questionnaire translation law. The Korean version of the INCR scale was assessed in 45 cardiac rehabilitation patients (29 males, 16 females). Internal consistency was verified using Cronbach's alpha. Test-re-test reliability and interrater reliability were verified using the intraclass correlation coefficient (ICC). Content validity was selected to verify the validity. Results: The content validity index of the Korean version of the INCR scale was high, with an average of 0.93. Cronbach's Alpha for Internal consistency also revealed high reliability of 0.89 in all 10 categories. The interclass correlation coefficient of the test-re-test and interrater reliability scores were 0.95 and 0.81, respectively. Conclusion: Our results indicate that the Korean version of the INCR scale would be instrumental in the clinical setting to determine the knowledge, educational needs, and preferences of patients participating in cardiovascular disease and cardiac rehabilitation.

전기체 구조시험의 덤프밸브 조절절차 개발; (Setup Procedure of Dump Valve for Full-Scale Airframe Test)

  • 김성찬;김성준;황인희
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.1252-1257
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    • 2003
  • This paper present a procedure of meter-out flow control method for dump valve in full-scale airframe test. Emergency stop, which results in dump state, can be happened during full-scale airframe test by several causes. Because servo valve can't control hydraulics actuator in the dump state, pressure in cylinder chamber may rise abruptly and overload can be acted to the test article. In this paper, the procedure and technology of orifice setting are investigated to protect the test article from unexpected loads by dump. The test results show that the presented methods decrease peak loads and improve unloading characteristics of hydraulic actuators in the dump state.

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On the Study for the Simultaneous Test

  • Park, Hyo-Il
    • Communications for Statistical Applications and Methods
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    • 제20권4호
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    • pp.241-246
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    • 2013
  • In this study, we propose a nonparametric simultaneous test procedure for the location translation and scale parameters. We consider the Wilcoxon rank sum test for the location translation parameter and the Mood test for the scale parameter with the quadratic and maximal types of combining functions. Then we derive the limiting null distributions of the combining functions. We illustrate our procedure with an example and compare efficiency by obtaining the empirical powers through a simulation study. Finally, we discuss some interesting features related to the nonparametric simultaneous tests.