• Journal of the Korean Statistical Society
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• v.24 no.2
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• pp.375-387
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• 1995

Main purpose of this article is to consider the asymptotic distribution of the rank transformed F statistic for interaction in a two-way layout. Some theorems and sufficient conditions are derived to have the rank transformed F statistic converged in distribution to a chi-squared random variable with (I-1)(J-1) degrees of freedom divided by (I-1)(J-1). These results will be useful for the other theoretical studies of the rank transform procedure in experimental designs.

• Communications for Statistical Applications and Methods
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• v.19 no.3
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• pp.451-457
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• 2012

Baumgartner et al. (1998) proposed a novel statistical test for the null hypothesis that two independently drawn samples of data originate from the same population, and Murakami (2006) generalized the test statistic for more than two samples. Whereas the expressions of the exact density and distribution functions of the generalized Baumgartner statistic are not yet found, the characteristic function of its limiting distribution has been obtained. Due to the development of computational power, the Fourier series approximation can be readily utilized to accurately and efficiently approximate its density function based on its Laplace transform. Numerical examples show that the Fourier series method provides an accurate approximation for statistical quantities of the generalized Baumgartner statistic.

• Proceedings of the KIEE Conference
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• 2007.11b
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• pp.207-209
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• 2007

For proper application of the superconducting fault current limiter(SFCL), the prior investigation of fundamental characteristics and its effects to the distribution systems are needed. The Current limiting behavior of SFCL is dominated by quenching and recovery characteristics. So, we have developed an EMTP/ATPDraw model of resistive type SCFL using MODELS language. The operating characteristics and current limiting behaviors of SFCL in distribution systems have been simulated and investigated.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2000.10a
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• pp.168-173
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• 2000

The limiting drawing ratio (LDR) under uniform heating of blanks was measured at the various temperature ranges between 25 and $250^{\circ}C$ by using two different blank shapes, square and circular blanks, and six different blank sizes with the drawing ratios(DR) of 2.4 to 2.9. The galvannealed steel sheet (SCP3CM 60/60) of 0.7mm thickness was used. The LDR at warm forming condition reached 1.2 times of that at room temperature, and the maximum drawing depth reached 1.9 times. The higher temperature was adopted, the more stable and uniform thickness strain distribution was observed.

• Journal of Mechanical Science and Technology
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• v.15 no.7
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• pp.839-846
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• 2001

Some deep drawing characteristics at elevated temperatures were investigated for the SCPI steel sheets by using a Cr-coated die. For this investigation, six different temperatures between room temperature and 250$\^{C}$, and six different drawing ratios ranging from 2.4 to 2.9 were considered. As a result, the limiting drawing ratio, the maximum drawing force and the maximum drawing depth were found to be affected sensitively by temperature, and more stable through-thickness strain distribution was observed at elevated temperatures. Some experimental results compared favorably with theoretical results obtained by using the finite element method.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.03b
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• pp.63-70
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• 1999

Some deep drawing characteristics to the elevated temperatures were investigated for the SCP1 steel sheets by using the Cr-coated die. For this investigations six steps of temperature ranges from room temperature to 25$0^{\circ}C$ and six kinds of drawing ratio from 2.4 to 2.9 were adopted. As a result the limiting drawing ration maximum drawing force and the maximum drawing depth were sensitively affected by the elevated temperatures and the more stable thickness strain distribution was observed to the elevated temperatures, Some experimental results were compared with analytical results using the DYNA-3D code.

• Journal of the Korean Statistical Society
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• v.26 no.3
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• pp.397-405
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• 1997

Recently maximum likelihood estimators using unconditional likelihood function are used for testing unit roots. When one wants to use this method the determinant term of initial values in the multivariate unconditional likelihood function produces a complicated function of the elements in the coefficient matrix and variance matrix. In this paper an approximation of the determinant term is calculated and based on this aproximation an approximated unconditional likelihood function is calculated. The approximated unconditional maximum likelihood estimators can be used to test for unit roots. When multivariate process has one unit root the limiting distribution obtained by this method and the limiting distribution using exact unconditional likelihood function are the same.

• Transactions of Materials Processing
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• v.11 no.5
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• pp.423-429
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• 2002

The limiting drawing ratio (LDR) under uniform heating of blanks was measured at the various temperature ranges between 25 and 25$0^{\circ}C$ by using two different blank shapes, square and circular blanks, and six different blank sizes with the drawing ratios(DR) of 2.4 to 2.9. The galvannealed steel sheet (SCP3CM 60/60) of 0.7mm thickness were used. The LDR at warm forming condition reached 1.2 times of that at room temperature, and the maximum drawing depth reached 1.9 times. The higher temperature was adopted, the more stable and uniform thickness strain distribution was observed. Some cases of the experimental results were compared with the analitical results using the commercial finite element method (FEM) code.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.10a
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• pp.143-150
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• 1999

The LRFD Specification defines two sets of limiting width-to-thickness ratios. On the basis of these limiting values, steel sections we subdivided into three categories: compact, noncompact, and slender sections. A compact section is capable of developing a fully plastic stress distribution (plastic moment), and can sustain rotations approximately three times beyond the yield before the possibility of local buckling arises. Noncompact sections can develop the yield stress before local buckling occurs. They may not, however, resist local buckling at the strain levels required to develop the fully plastic stress distribution. In this paper, 1-Type girders of a 2 span continuous steel bridge are divided into compact and non-compact sections and analyzed. In the design process, an optimization skill was adopted and ADS, a Fortran program for Automated Design Synthesis, was used.

• Transactions of Materials Processing
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• v.9 no.2
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• pp.186-192
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• 2000

Some deep drawing characteristics to the elevated temperatures were investigated for the SCPI steel sheets by using the Cr-coated die. For this investigations, six steps of temperature ranges, from room temperature to 25$0^{\circ}C$, and six kinds of drawing ratio, from 2.4 to 2.9 were adopted. As a result, the limiting drawing ratio, maximum drawing force, and the maximum drawing depth were sensitively affected by the elevated temperatures, and the more stable thickness strain distribution was observed to the elevated temperatures. Some experimental results were compared with analytical results using the DYNA-3D code.