• Journal of the Korean Data and Information Science Society
• /
• v.28 no.1
• /
• pp.143-152
• /
• 2017

Restriction of completely randomization within a block can be handled by a split plot factorial design splitted by several plots. $3{\times}3$ split plot factorial design with two fixed main factors and one fixed block shows that powers of the rank transformed statistic for testing whole plot factorial effect and split plot factorial effect are superior to those of the parametric statistic when existing effect size is small or the remaining effect size is relatively smaller than the testing factorial effect size. Powers of the rank transformed statistic show relatively high level for exponential and double exponential distributions, whereas powers of the parametric and rank transformed statistic maintain similar level for normal and uniform distributions. Powers of the parametric and rank transformed statistic with two fixed main factors and one random block are respectively lower than those with all fixed factors. Powers of the parametric andrank transformed statistic for testing split plot factorial effect with two fixed main factors and one random block are slightly lower than those for testing whole plot factorial effect, but powers of the rank transformed statistic show comparative advantage over those of the parametric statistic.

• Journal of the Korean Mathematical Society
• /
• v.38 no.6
• /
• pp.1117-1123
• /
• 2001

A ring is a DICC ring if every chain of right ideals in-dexed by the integers stabilizes to the left or to the right or to both sides. A counterexample is given to an assertion of karamzadeh and Motamedi that a transfinite power of the Jacobson radical of a right DICC ring is zero. we determine the behavior of the transfinite powers of the Jacobson radical relative to a torsion theory and consequently can obtain their correct behavior in the classical setting.

• Proceedings of the KIEE Conference
• /
• 1997.07f
• /
• pp.1930-1932
• /
• 1997

Instantaneous active/reactive powers are defined in three phase four wire systems. The definition can be generally applicable to any source conditions and load conditions including nonlinear circuits. The zero-sequence power resulted from the zero-sequence voltage and zero-sequence current between two sub-systems affects both to the instantaneous active and reactive powers. The zero-sequence current can be controlled by compensation of the reactive power without power storage elements.

• Proceedings of the KIPE Conference
• /
• 1997.07a
• /
• pp.228-232
• /
• 1997

The relation between instantaneous active/reactive powers and currents is defined by voltage mapping matrix in three-phase four-wire systems. Control strategies for an active filter without energy storage components are proposed on the basis of mapping matrices. It can compensate for the zero-sequence current, irrespectively of whether or not a zero-sequence voltage exists in a three-phase four-wire system.

• Communications for Statistical Applications and Methods
• /
• v.9 no.3
• /
• pp.639-647
• /
• 2002

Efforts to obtain more power for unit root tests have continued. Pantula at el.(1994) compared empirical powers of several unit root test statistics and addressed that the weighted symmetric estimator(WSE) and the unconditional maximum likelihood estimator(UMLE) are the best among them. One can easily see that the powers of these two statistics are almost the same. In this paper we explain a connection between WSE and UMLE and suggest a unit root test statistic which may explain the connection between them.

• Journal of the Korean Statistical Society
• /
• v.32 no.2
• /
• pp.93-101
• /
• 2003

This paper deals with testing the equality of the coefficients of variation in two inverse Gaussian populations. The likelihood ratio, Lagrange-multiplier and Wald tests are presented. Monte-Carlo simulations are performed to compare the powers of these tests. In a simulation study, the likelihood ratio test appears to be consistently more powerful than the Lagrange-multiplier and Wald tests when sample size is small. The powers of all the tests tend to be similar when sample size increases.

• Journal of applied mathematics & informatics
• /
• v.8 no.2
• /
• pp.669-682
• /
• 2001

In this paper a nonparametric test for the parallelism of k regression lines against ordered alternatives, when the independent variables are positive and all regression lines have a common intercept is proposed. The proposed test is based on a Jonckheere-type statistic applied to residuals. Under some conditions the proposed test statistic is asymptotically distribution-free. The small-sample powers of our test are compared with other tests by a Monte Carlo study. The simulation results show that the proposed test has significantly higher empirical powers than the other tests considered in this paper.

• Bulletin of the Korean Mathematical Society
• /
• v.57 no.5
• /
• pp.1231-1240
• /
• 2020

The asymptotic behavior of graded Betti numbers of powers of homogeneous ideals in a polynomial ring over a field has recently been reviewed. We extend quasi-polynomial behavior of graded Betti numbers of powers of homogenous ideals to ℤ-graded algebra over Noetherian local ring. Furthermore our main result treats the Betti table of filtrations which is finite or integral over the Rees algebra.

• Communications for Statistical Applications and Methods
• /
• v.4 no.2
• /
• pp.565-579
• /
• 1997

A robust test is proposed for the problem of testing the parallelism of several regression lines against ordered alternatives. The proposed test statistic is based on a linear combination of one-step pairwise GM-estimators. We compare the performance of the proposed test with that of the other tests through a Monte Carlo simulation. The results of the simulation study show that the proposed test has stable levels, good empirical powers in various circumstances, and particularly higher empirical powers under the presence of extreme outliers or leverage points.

• Journal of the Korean Mathematical Society
• /
• v.39 no.3
• /
• pp.351-361
• /
• 2002

We extend the Holder-McCarthy inequality for a positive and an arbitrary operator, respectively. The powers of each inequality are given and the improved Reid's inequality by Halmos is generalized. We also give the bound of the Holder-McCarthy inequality by recursion.