• Journal of the Korean Statistical Society
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• v.23 no.1
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• pp.13-32
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• 1994

Let A(n) and B(n) be sequences of $m \times m$ random matrices with a joint asymptotic distribution as $n \to \infty$. The asymptotic distribution of the ordered roots of $$\mid$A(n) - f B(n)$\mid$ = 0$ depends on the multiplicity of the roots of a determinatal equation involving parameter roots. This paper treats the asymptotic distribution of the roots of the above determinantal equation in the case where some of parameter roots are zero. Furthermore, we apply our results to deriving the asymptotic distributions of the eigenvalues of the MANOVA matrix in the noncentral case when the underlying distribution is not multivariate normal and some parameter roots are zero.

• Journal of Applied Reliability
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• v.11 no.3
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• pp.225-234
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• 2011

In the fields of reliability application, the most commonly used test methods for reliability qualification are zero-failure acceptance tests since they require fewer test samples and less test time compared to other test methods that guarantee the same reliability with a given confidence level. Usually values of shape parameters are assumed to be known in designing reliability qualification tests for Weibull lifetime distribution. It is important to select correct values of shape parameters to guarantee the specified reliability with given confidence level exactly. The effect of using wrong values of shape parameters in designing reliability qualification test for products with Weibull lifetime distribution is examined and selecting proper values of shape parameters for conservative reliability qualification is discussed.

• Journal of Magnetics
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• v.22 no.1
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• pp.1-6
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• 2017

Magnetic properties of CoPt nanoparticles (average size = 2.1 nm) encapsulated in synthesized protein shell have been investigated with SQUID (Superconducting Quantum Interference Device) magnetometer and analyzed by the recently developed non-equilibrium magnetization calculation by our group [T. H. Lee et al., Phys. Rev. B 90, 184411 (2014)]. Field dependence of magnetization measured at 2 K was successfully analyzed with modified Langevin function. In addition, small hysteresis loops having the coercive field of 890 Oe were observed at 2 K. Temperature dependence of magnetization has been measured with zero field cooled (ZFC) and field cooled (FC) protocol with slightly modified sequence in accordance with non-equilibrium magnetization calculation. The analysis on the M vs. T data revealed that the anisotropy energy barrier distribution is found to be very different from the log-normal distribution found in a size distribution. Zero temperature coercive field and Bloch coefficient have also been extracted from the analysis and the validity of those values is checked.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.120-123
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• 1993

This paper presents the developing a new algorithm for detecting the Back fed Earth Fault in three wire-unigrounded distribution system by zero sequence admittance. So called "Backfed Earth Fault" of the electric power distribution line refers to a class of earth faults that the load-side line only is grounded, following after the distribution line broken into two parts, the source-side and the load-side. Because its mechanism differs from that of other earth faults, it is therefore, required to examine. This paper deals with the detailed software of the digital protective relay for Backfed earth fault. In order to prove that the proposed schemes is good, we performed off-line simulation using data from EMTP and ETSA(Electrcity Trust Of South Austrilia). It is shown that the suggested algorithm is never mal operated.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 1991.11a
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• pp.85-94
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• 1991

Fiat, Shamir의 ZKIP(zero knowledge interactive proofs) 방식을 이용한 새로운 키분배방식을 제안한다. 본 방식은 평방잉여를 이용한 Fiat, Shamir의 ZKIP 방식을 이용하여 상호인증을 행하고 그 과정에서 교환되는 데이타를 사용하여 비밀통신용 공통키를 생성한다. 공통키 생성 과정에 사용된 데이타가 인증 과정에서 사용된 데이타이고, 인증 과정은 ZKIP 방식을 이용했으므로 제안한 키분배방식 역시 zero knowledge일 것으로 생각되며 ZKIP 방식은 인증 과정의 반복으로 인한 통신량이 많은 반면 제안한 방식은 인증과정에서의 반복횟수가 1이기 때문에 상대적으로 통신량이 적은 이점이 있다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.2
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• pp.117-132
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• 2018

There always exist nonzero inspection errors whether inspectors are humans or automatic inspection machines. Inspection errors can be categorized by two types, type I error and type II error, and they can be regarded as either a constant or a random variable. Under the assumption that two types of random inspection errors are distributed with the "uniform" distribution on a half-open interval starting from zero, it was proved that inspectors overestimate any given fraction defective with the probability more than 50%, if and only if the given fraction defective is smaller than a critical value, which depends upon only the ratio of a type II error over a type I error. In addition, it was also proved that the probability of overestimation approaches one hundred percent as a given fraction defective approaches zero. If these critical phenomena hold true for any error distribution, then it might have great economic impact on commercial inspection plans due to the unfair overestimation and the recent trend of decreasing fraction defectives in industry. In this paper, we deal with the same overestimation problem, but assume a "symmetrical triangular" distribution expecting better results since our triangular distribution is closer to a normal distribution than the uniform distribution. It turns out that the overestimation phenomenon still holds true even for the triangular error distribution.

• Journal of the Korean Data and Information Science Society
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• v.20 no.2
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• pp.459-465
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• 2009

For an inverse double Weibull distribution which is symmetric about zero, we obtain distribution and moment of ratio of independent inverse double Weibull variables, and also obtain the cumulative distribution function and moment of a skew-symmetric inverse double Weibull distribution. And we introduce a skew-symmetric inverse double Weibull generated by a double Weibull distribution.

• The Korean Journal of Applied Statistics
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• v.27 no.2
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• pp.345-355
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• 2014

The number of nonconformities in a unit is commonly modeled by a Poisson distribution. As an extension of a Poisson distribution, a zero-inflated Poisson(ZIP) process can be used to fit count data with an excessive number of zeroes. In this paper, we propose a generalized likelihood ratio(GLR) chart to monitor shifts in the two parameters of the ZIP process. We also compare the proposed GLR chart with the combined cumulative sum(CUSUM) chart and the single CUSUM chart. It is shown that the overall performance of the GLR chart is comparable with CUSUM charts and is significantly better in some cases where the actual directions of the shifts are different from the pre-specified directions in CUSUM charts.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.3
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• pp.193-204
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• 2022

The 2018 Seoul Zero Pay is a policy actively promoted by the government as an economic stimulus package for small business owners and the self-employed who are experiencing economic depression due to COVID-19. However, the controversy over the effectiveness of Zero Pay continues even after two years have passed since the implementation of the policy. Zero Pay is a joint QR code mobile payment service introduced by the government, Seoul city, financial companies, and private simple payment providers to reduce the burden of card merchant fees for small business owners and self-employed people who are experiencing economic difficulties due to the economic downturn., it was attempted in the direction of economic revitalization for the return of alleyways[1]. Therefore, this study intends to draw implications for improvement measures so that the ongoing zero-pay can be further activated and the economy can be settled normally. The analysis results of this study are as follows. First, it shows the effect of increasing the income of small business owners by inducing consumption in alleyways through the economic revitalization policy of Zero Pay. Second, the issuance and distribution of Zero Pay helps to revitalize the local economy and contribute to the establishment of a virtuous cycle system. Third, stable operation is being realized by the introduction of blockchain technology to the Zero Pay platform. In terms of academic significance, the direction of Zero Pay's policies and systems was able to identify changes in the use of Zero Pay through big data analysis. The implementation of the zero-pay policy is in its infancy, and there are limitations in factors for examining the consumer image perception of zero-pay as there are insufficient prior studies. Therefore, continuous follow-up research on Zero Pay should be conducted.

• Journal of the Korean Mathematical Society
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• v.41 no.4
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• pp.755-772
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• 2004

We show that the Fourier-Laplace series of a distribution on the sphere is uniformly Cesaro-summable to zero on a neighborhood of a point if and only if this point does not belong to the support of the distribution. Similar results on the ball and on the real projective space are also proved.