• Journal of the Korean Mathematical Society
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• v.32 no.1
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• pp.77-84
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• 1995

Many authors have utilized an exponential distribution because of its wide applicability in reliability engineering and statistical inferences (see Bain & Engelhart(1987) and Saunders & Mann(1985)). Here we are considering the parametric estimation in an exponential distribution when its scale and location parametes are linear functions of a known exposure level t, which often occurs in the engineering and physical phenomena.

• Journal of Korean Society for Quality Management
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• v.14 no.1
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• pp.39-46
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• 1986

This paper considers two sided tests for exponential null distribution against NBUE or NWUE alternative in life testing. The main results concern the strong consistency of two proposed statistics, one being similar to Kolmogorov - Smirnov statistic, the other similar to Cramer-Von Mises statistic. Also obtained are the asymtotic null distribution and the exact Bahadur slope of the statistic similar to Kolmogorov-Smirnov.

• Journal of the Korean Statistical Society
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• v.26 no.1
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• pp.47-56
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• 1997

The asymptotic distribution of the extended Yule-Walker estimates of a mixed ARMA process is derived. Also, a recursive algorithm is derived to calculate the extended Yule-Walker estimates recursively, which is a generalization of the Levinson-Durbin algorithm.

• International Journal of Reliability and Applications
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• v.9 no.2
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• pp.153-165
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• 2008

This paper discusses the reliability equivalences of a series-parallel system. The system components are assumed to be independent and identical. The failure rates of the system components are functions of time and follow Weibull distribution. Three different methods are used to improve the given system reliability. The reliability equivalence factor is obtained using the reliability function. The fractiles of the original and improved systems are also obtained. Numerical example is presented to interpret how to utilize the obtained results.

• Journal of the Korean Mathematical Society
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• v.42 no.1
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• pp.171-189
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• 2005

In this paper, we first establish some characterization of tightness for a sequence of random elements taking values in the space of normal and upper-semicontinuous fuzzy sets with compact support in $R^P$. As a result, we give some sufficient conditions for a sequence of fuzzy random sets to converge in distribution.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.1
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• pp.33-39
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• 1986

Particulate matter was collected by Andersen Air Sampler in the Seoul area during February-October, 1985, in order to investigate size distribution of sulfate and nitrate in aerosol, and conversion of sulfur dioxide to sulfate and that of nitrogen dioxide to nitrate. The size distribution of sulfate and nitrate had fine mode. The ratio of fine sulfate to total sulfate in aerosol and that of fine nitrate to total nitrate showed between 54.6% and 86%, and 55.7% and 95%, respectively, which presumably originated from gaseous reaction of sulfur dioxide and nitrogen dioxide in the atmosphere.

• Journal of Korean Society for Quality Management
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• v.22 no.1
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• pp.162-168
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• 1994

In this paper we develop an unconditional method for inferences on the shape parameter of a gamma distribution. A simple numerical implementation of this unconditional method is developed; this is a computer program that takes the observed data as input and produces the confidence distribution function for the shape parameter, which in turn provides approximate observe significance levels and confidence intervals for that parameter, as output. These approximations are extremely accurate even for very small sample size and numerically simple and easy to obtain.

• The Korean Journal of Applied Statistics
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• v.22 no.5
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• pp.1097-1102
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• 2009

Classification of subjects with unknown distribution in small sample size setup may involve order-restricted constraints in multivariate parameter setups. Those problems makes optimality of conventional likelihood ratio based statistical inferences not feasible. Fortunately, Roy (1953) introduced union-intersection principle(UIP) which provides an alternative avenue. Redescending M-estimator along with that principle yields a considerably appropriate robust testing procedure. Furthermore, conditionally distribution-free test based upon exact permutation theory is used to generate p-values, even in small sample. Applications of this method are illustrated in simulated data and read data example (Lobenhofer et al., 2002)

• Journal of applied mathematics & informatics
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• v.26 no.3_4
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• pp.733-738
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• 2008

Using an information of dimensions of divergence points, we give full information of dimensions of the completely decomposed class of the lower(upper) distribution sets of a self-similar Cantor set. Further using a relationship between the distribution sets and the subsets generated by the lower(upper) local dimensions of a self-similar measure, we give full information of dimensions of the subsets by the local dimensions.

• Journal of applied mathematics & informatics
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• v.35 no.5_6
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• pp.651-657
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• 2017

A sequence {$X_n,\;n{\geq}1$} of independent and identically distributed random variables with absolutely continuous (with respect to Lebesque measure) cumulative distribution function F(x) is considered. We obtain two characterizations of a family of continuous probability distribution by independence property of record values.