• 제목/요약/키워드: Mean testing

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A NEW UDB-MRL TEST WITH UNKNOWN CHANCE POINT

  • Na, Myung-Hwan
    • 품질경영학회지
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    • 제30권3호
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    • pp.195-202
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    • 2002
  • The problem of trend change in the mean residual life is great Interest in the reliability and survival analysis. In this paper, a new test statistic for testing whether or not the mean residual life changes its trend Is developed. It is assumed that neither the change point nor the proportion at which the trend change occurs is known. The asymptotic null distribution of test statistic is established and asymptotic critical values of the asymptotic null distribution is obtained. Monte Carlo simulation is used to compare the proposed test with previously known tests.

A Family of Tests for Trend Change in Mean Residual Life using Censored Data

  • Na, Myung-Hwan;Kim, Jae-Joo
    • International Journal of Reliability and Applications
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    • 제1권1호
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    • pp.39-47
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    • 2000
  • In a resent paper, Na and Kim(2000) develop a family of test statistics for testing whether or not the mean residual life changes its trend based on complete data and show that the new tests perform better than previously known tests. In this paper, we extend their tests to the randomly censored data. The asymptotic normality of the test statistics is established. Monte Carlo simulations are conducted to compare our tests with a previously known test by the power of tests.

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A NEW UDB-MRL TEST FOR WITH UNKNOWN

  • Na, Myung-Hwan
    • 품질경영학회지
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    • 제30권4호
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    • pp.78-85
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    • 2002
  • The problem of trend change in the mean residual life is great interest in the reliability and survival analysis. In this paper, a new test statistic for testing whether or not the mean residual life changes its trend is developed. It is assumed that neither the change point nor the proportion at which the trend change occurs is known. The asymptotic null distribution of test statistic is established and asymptotic critical values of the asymptotic null distribution is obtained. Monte Carlo simulation is used to compare the proposed test with previously known tests.

SPECT 회전중심 측정에 있어서 콜리메타의 영향 (The Influence of Collimators on SPECT COR Measurements)

  • 이만구
    • 대한방사선기술학회지:방사선기술과학
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    • 제19권1호
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    • pp.89-94
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    • 1996
  • Misalignment between the electronic and mechanical axes of rotation will result in artifact generation and image degradation during single photon emission computed tomography(SPECT) reconstruction. Acceptance and quality control testing procedures have not emphasized the variability in center of rotation(COR) measurements caused by collimators and the need to verify uniformity across the full collimator field of view (FOV). Variation from the mean COR across the FOV was tested in four different collimators using multiple point source acquisitions. The mean COR was different for each collimator and one of the four had a > 0.5 pixel difference from the mean COR on some area of the FOV, This variation makes this collimator unacceptable for SPECT acquisition. Thus, initial acceptance testing of SPECT collimators should verify a uniform COR across the full FOV and collimators with a variability from the mean COR > 0.5 pixels should be rejected.

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호스피스 환자의 영적 안녕 상태에 관한 조사 연구 (A Study on the Spiritual Wellbeing of the Hospice Patients)

  • 김정남;송미옥
    • 한국보건간호학회지
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    • 제17권2호
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    • pp.255-265
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    • 2003
  • This study was conducted to provide a baseline data for hospice nurses to improve their practices for the spiritual wellbeing of their clients. Analysis of the spiritual wellbeing status of hospice patients was conducted from April 20 to June 20, 2002. A total of 59 cancer patients who admitted to hospice care units of one university medical center, and who have alert mental status were recruited for the study. Paloutzian and Ellison (982) spiritual wellbeing scale and Jungho Kang (996) scale, which was modified for the cancer patients, were used as the study instruments, ANOVA and T-test were applied using SPSS win 10.0 for statistical analysis. The results are as follows : 1. The mean spiritual wellbeing score of the hospice patients was $49.76(SD\pm7.95)$. When it was converted into 4 point scale, the mean score for the spiritual wellbeing was 2.49. The mean religious wellbeing score was $24.17 (SD\pm5.56)$ and that of the existential wellbeing was $25.59 (SD\pm3.10)$. 2 The mean score for the total spiritual wellbeing was $52.54 (SD\pm8.12)$ for female, and $47.86 (SD\pm6.95)$ for male and the difference was statistically significant (t=-2.305, p=.025), 3. In testing the spiritual wellbeing, there was significant difference according to the religion (F=28.931, p=.000). 4. In testing the religious wellbeing, the mean score was $22.77 (SD\pm5.35)$ for male, and $26.20 (SD\pm5.32)$ for female and the difference was statistically significant (t=-2.430, p=.019). 5. In testing the religious wellbeing, there was significant difference according to the religion (F=37.522, p=.000). However, the religious wellbeing was not different according to the age, occupation, marital status and education level. 6. In testing the existential wellbeing. there was significant difference according to the religion (F=8.147, p=.000). However, mean score for the existential wellbeing was not significantly different according to sex, age, occupation, marital status and education level. 7. In testing the existential wellbeing, there was significant difference according to the level of vigor (F=3.662, p=.032), while no difference was observed in the existential wellbeing according to the general health status, degree of pain, and diagnosis. From the results described above it can be concluded that : To improve the spiritual wellbeing status of hospice patients, hospice nurses should identify spiritual needs of the patients according to the religion. gender and the level of vigor.

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비파괴충격파 시험법을 이용한 동탄성계수 평가 (Evaluation of the Dynamic Modulus by using the Impact Resonance Testing Method)

  • 김도완;장병관;문성호
    • 한국도로학회논문집
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    • 제16권3호
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    • pp.35-41
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    • 2014
  • PURPOSES : The dynamic modulus for a specimen can be determined by using either the non-destructed or destructed testing method. The Impact Resonance Testing (IRT) is the one of the non-destructed testing methods. The MTS has proved the source credibility and has the disadvantages which indicate the expensive equipment to operate and need a lot of manpower to manufacture the specimens because of the low repeatability with an experiment. To overcome these shortcomings from MTS, the objective of this paper is to compare the dynamic modulus obtained from IRT with MTS result and prove the source credibility. METHODS : The dynamic modulus obtained from IRT could be determined by using the Resonance Frequency (RF) from the Frequency Response Function (FRF) that derived from the Fourier Transform based on the Frequency Analysis of the Digital Signal Processing (DSP)(S. O. Oyadigi; 1985). The RF values are verified from the Coherence Function (CF). To estimate the error, the Root Mean Squared Error (RMSE) method could be used. RESULTS : The dynamic modulus data obtained from IRT have the maximum error of 8%, and RMSE of 2,000MPa compared to the dynamic modulus measured by the Dynamic Modulus Testing (DMT) of MTS testing machine. CONCLUSIONS : The IRT testing method needs the prediction model of the dynamic modulus for a Linear Visco-Elastic (LVE) specimen to improve the suitability.

로지스틱 테스트 노력함수를 이용한 소프트웨어의 최적인도시기 결정에 관한 연구 (A Study on the Optimal Release Time Decision of a Developed Software by using Logistic Testing Effort Function)

  • 최규식;김용경
    • Journal of Information Technology Applications and Management
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    • 제12권2호
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    • pp.1-13
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    • 2005
  • This paper proposes a software-reliability growth model incoporating the amount of testing effort expended during the software testing phase after developing it. The time-dependent behavior of testing effort expenditures is described by a Logistic curve. Assuming that the error detection rate to the amount of testing effort spent during the testing phase is proportional to the current error content, a software-reliability growth model is formulated by a nonhomogeneous Poisson process. Using this model the method of data analysis for software reliability measurement is developed. After defining a software reliability, This paper discusses the relations between testing time and reliability and between duration following failure fixing and reliability are studied. SRGM in several literatures has used the exponential curve, Railleigh curve or Weibull curve as an amount of testing effort during software testing phase. However, it might not be appropriate to represent the consumption curve for testing effort by one of already proposed curves in some software development environments. Therefore, this paper shows that a logistic testing-effort function can be adequately expressed as a software development/testing effort curve and that it gives a good predictive capability based on real failure data.

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EMPIRICAL BAYES TESTING FOR MEAN LIFE TIME OF RAYLEIGH DISTRIBUTION

  • Liang, TaChen
    • Journal of applied mathematics & informatics
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    • 제25권1_2호
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    • pp.1-15
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    • 2007
  • Consider a Rayleigh distribution with $$pdf\;p(x/{\theta})\;=\;2x{\theta}^{-1}\;{\exp}\;({-x^2}/{\theta})$$ and mean lifetime ${\mu}\;=\;\sqrt{\pi\theta}/2$. We study the two-action problem of testing the hypotheses $H_{0}\;:\;{\mu}{\leq}{\mu}_{0}$ against $H_{1}\;:\;{\mu}\;>\;{\mu}_{0}$ using a linear error loss of ${\mid}{\mu}\;-\;{\mu}_{0}{\mid}$ via the empirical Bayes approach. We construct a monotone empirical Bayes test ${\delta}^{*}_{n}$ and study its associated asymptotic optimality. It is shown that the regret of ${\delta}^{*}_{n}$ converges to zero at a rate $\frac{{\ln}^{2}n}{n}$, where n is the number of past data available when the present testing problem is considered.

A Two Sample Test for Functional Data

  • Lee, Jong Soo;Cox, Dennis D.;Follen, Michele
    • Communications for Statistical Applications and Methods
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    • 제22권2호
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    • pp.121-135
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    • 2015
  • We consider testing equality of mean functions from two samples of functional data. A novel test based on the adaptive Neyman methodology applied to the Hotelling's T-squared statistic is proposed. Under the enlarged null hypothesis that the distributions of the two populations are the same, randomization methods are proposed to find a null distribution which gives accurate significance levels. An extensive simulation study is presented which shows that the proposed test works very well in comparison with several other methods under a variety of alternatives and is one of the best methods for all alternatives, whereas the other methods all show weak power at some alternatives. An application to a real-world data set demonstrates the applicability of the method.

Microsatellite DNA형 분석을 이용한 더러브렛 말의 친자감정 (Parentage Testing for Thoroughbred Horse by Microsatellite DNA Typing)

  • 조길재
    • Journal of Animal Science and Technology
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    • 제46권2호
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    • pp.129-136
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    • 2004
  • The objective of present study was to ascertain parentage of Thoroughbred(TB) horses in Korea. A total of 2,029 TB horse samples including 993 foal samples for parentage testing were genotyped for nine international minimum standard markers(AHT4, 5, ASB2, HMS3, 6, 7, HTG4, 10, and VHL20). This method consisted of multiplexing PCR procedure, and showed reasonable amplification of all PCR products. Genotyping was performed with an ABI 310 genetic analyzer. The number of alleles per locus varied from 5 to 11 with a mean value of 7.33 in TB. Expected heterozygosity was ranged from 0.544 to 0.837(mean 0.709) and the total exclusion probability of 9 microsatellites loci was 0.9978. Of the 9 markers, ASB2, HMS7 and HTG10 loci have relatively high PIC value(>0.7). All of the 993 foals were qualified by compatibility according to Mendelian fashion in the present DNA typing for parentage testing. These results suggest that the present DNA typing has high potential for parentage verification of TB horses.