• Journal of the Korean Statistical Society
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• v.30 no.1
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• pp.153-161
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• 2001

In this paper, a strong law of large numbers for sums of stationary and ergodic fuzzy random variables is obtained.

• Proceedings of the Korean Statistical Society Conference
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• 2003.10a
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• pp.183-188
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• 2003

In this paper, we establish some results on strong convergence for weighted sums of uniformly integrable fuzzy random variables taking values in the space of upper-semicontinuous fuzzy sets in R$^{p}$.

• Korean Journal of Mathematics
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• v.16 no.4
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• pp.573-581
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• 2008

We obtain an improvement of strong laws of large numbers for independent fuzzy random variables.

• Structural Engineering and Mechanics
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• v.60 no.3
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• pp.413-431
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• 2016

A sensitivity analysis estimates the effect of the change in the uncertain variable parameter on the probability of the structural failure. A novel fuzzy random reliability sensitivity measure of the failure probability is proposed to consider the effect of the epistemic and aleatory uncertainties. The uncertainties of the engineering variables are modeled as fuzzy random variables. Fuzzy quantities are treated using the ${\lambda}$-cut approach. In fact, the fuzzy variables are transformed into the interval variables using the ${\lambda}$-cut approach. Genetic approach considers different possible combinations within the search domain (${\lambda}$-cut) and calculates the parameter sensitivities for each of the combinations.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.7
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• pp.363-369
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• 2000

To flexibly evaluate performance and reliability of an electric power system in the aspect of the real-time system which is intrinsically characterized by stringent timing constraints fails catastrophically if its control input is not updated by its digital controller computer within a certain time limit called the hard deadline, we propose fuzzy-random variables and build a discrete event model embedded with fuzzy-random variables. Also, we adapt fuzzy-variables to a path-space approach, which derives the upper and lower bounds of reliability by using a semi-Markov model that explicitly contains the deadline information. Consequently, we propose certain formulas of state automata properly transformed by fuzzy-random variables, and present numerical examples applying the formulas as well.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.1
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• pp.98-103
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• 2005

In this paper, we consider interval number-valued random variables and fuzzy number-valued random variables and discuss Choquet integrals of them. Using these properties, we define the Choquet expected value of fuzzy number-valued random variables which is a natural generalization of the Lebesgue expected value of fuzzy random variables. Furthermore, we discuss some application of them.

• Korean Journal of Mathematics
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• v.14 no.2
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• pp.291-302
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• 2006

In this paper, we give sufficient conditions for a.s. convergence of weighted sums of integrable fuzzy random variables. As a result, we obtain strong laws of large numbers for weighted sums of independent fuzzy random variables.

• Communications for Statistical Applications and Methods
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• v.12 no.2
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• pp.275-283
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• 2005

In this paper, we give a sufficient condition for convergence in probability of weighted sums of convex-compactly uniformly integrable fuzzy random variables. As a result, we obtain weak law of large numbers for weighted sums of convexly tight fuzzy random variables.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.9 no.2
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• pp.147-153
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• 2009

In this paper, we introduce several concepts of tightness for a sequence of random variables taking values in the space of normal and upper-semicontinuous fuzzy sets with compact support in $R^p$ and give some characterizations of their concepts. Also, counter-examples for the relationships between the concepts of tightness are given.

• Journal of the Korean Statistical Society
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• v.32 no.1
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• pp.73-83
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• 2003

In this paper, we first obtain some characterizations of compact subsets of the space of level-wise continuous fuzzy numbers in R by the modulus of continuity. Using this, we establish the tightness for a sequence of level-wise continuous fuzzy random variables.