• International Journal of Automotive Technology
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• v.7 no.7
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• pp.859-866
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• 2006

This study employed the perturbation method, the Edgeworth series, the reliability optimization, the reliability sensitivity technique and the robust design to present a practical and effective approach for the robust reliability design of vehicle components with arbitrary distribution parameters on the condition of known first four moments of original random variables. The theoretical formulae of the robust reliability design for vehicle components with arbitrary distribution parameters are obtained. The reliability sensitivity is added to the reliability optimization design model and the robust reliability design is described as a multi-objection optimization. On the condition of known first four moments of original random variables, the respective program can be used to obtain the robust reliability design parameters of vehicle components with arbitrary distribution parameters accurately and quickly.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.3 s.168
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• pp.187-193
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• 2005

The temperature distribution of the deposited droplet was predicted by using the finite element analysis and it was assumed that the droplet was axisymmetrical model. The analysis of residual stress was performed with the temperature data, which is obtained from the result. Axisymmetric droplet is deposited three times to consider the actual phenomenon of droplet deposition. The analysis of the temperature distribution is respectively performed whenever the axisymmetric droplet is laminated and the residual stresses of the laminated axisymmetric droplet are calculated with the value of the temperature distribution.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.3
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• pp.345-358
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• 2014

For introducing the groundwater quality assessment using background concentration of groundwater, several methods had been studied to estimate the background concentration of groundwater and to suggest the background concentration of study area. Some methods such as Box whisker plot, Percentile and Cumulative probability distribution had been adopted to estimate background concentration, and it was evaluated that the Cumulative probability distribution method presents more reasonable background concentration because it can consider the data distribution. So we estimated the background concentration of study area using cumulative probability distribution method. We suggested the background concentration for each hydrogeology respectively in case hydrogeological water quality similarity is very low.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.1
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• pp.53-61
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• 2001

This study was carried out to evaluate the effect of coating pigments on the printability by investigating the pore structure of casting layer such as the number, size and distribution of pores and the pore rate. The coating structure was mainly determined by the interaction between pigment and binder. It means that the structure of pores was chiefly affected by the shape and size distribution of pigments and their packing rate. The physical properties of pore have close relationships with ink set-off, the speed of ink penetration and printing gloss. The results suggested that the rate and number of pores were greatly affected by the particle size distribution and shape of pigments. The rate of pore increased with the reduction of particle size distribution of pigments. Calcite was effective to improve greatly the printability of coated paper.

• Journal of Ocean Engineering and Technology
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• v.10 no.3
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• pp.3-13
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• 1996

An extensive research programme has been aimed at the effct of ship weight distribution on the ship responses applying ship hydroelasticity theory. In the previous works, consistent tendencies of the still-water and the wave bending moments. respectively, were found as the weight distribution was varied systematically. The paper is therefore concerned mainly with any correlation between still-water and wave bending moments with the variations of weight distribution. Although these bending moments share different features with each other, such a comparison of tendencies was plausible and informative. These and other matters for the future are discussed.

• Journal of the Korean Ceramic Society
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• v.30 no.3
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• pp.199-205
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• 1993

Effects of grain size distribution on the breakdown voltage of ZnO varistors were investigated in the ZnO-Bi2O3-CoO-Sb2O3 and ZnO-Bi2O3-CoO-Sb2O3-Cr2O3 systems, respectively. The grain size was increased with increasing sintering temperature maintaining lognormal distribution in both systems. The width of grain size distribution of ZnO-Bi2O3-CoO-Sb2O3 system was narrower than that of ZnO-Bi2O3-CoO-Sb2O3 system. The breakdown voltage(Vb) was decreased by increasing sintering temperature(1000~135$0^{\circ}C$) and sintering time(0.5~5hr), due to the enhancement of ZnO grain growth. The current path of the ZnO varistor was dependent on the distribution of the largest grains (chains of long grains) between the electrodes.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.817-825
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• 1998

A three-dimensional ecosystem model is applied to the Suyoung Bay, located at the southeastern part of Korea, to study of the material distribution in the time scale of several tens days. The model has included of the DIN(Dissolved Inorganic Nitrogen), DIP(Dissolved Inorganic Phosphate), phytoplankton, zooplankton and detritus, and also was coupled with the physical processes. The spatial distribution of chlorophyll-a and primary productivity in the model is determined by the physical and chemical-biological parameters. The horizontal distributions of the DIN, DIP and chlorophyll-a are decreased from the coast to the off-shore, though the nutrients show some more complicated pattern than the chlorophyll-a. The nutrient contents in the off-shore are low, and thus a relatively low productivity(chlorophyll-a) are presented. On the whole, the distribution of the results of model are smoother than the observed ones and some small scale variation in the observed data cannot be reproduced by the model due to the resolution limits of model. However, the basic pattern and the quantitavities has been reproduced by the model well.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.9
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• pp.81-86
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• 2007

Electric utility companies have the responsibility of providing good electricity for their customers. They have introduced the DAS(Distribution Automation System) to automate the power distribution networks. DAS engineers require state-of-the-art applications, such as a way to actively manage the distribution system and gain economic benefits from a flexible DAS architectural design. The existing DAS is not capable of handling these needs. It requires operator intervention whenever feeder overloading is detected while operator error could cause the feeder overload area to be extended. It also utilizes a closed architecture and it is therefore difficult to meet the system migration and future enhancement requirements. This paper represents a web based, platform-independent, flexible DAS architectural design and active database application. Recent advanced Internet technologies are fully utilized in this new DAS architecture allowing it to meet the system migration and future enhancement requirements. By using an active database, the DAS can minimize the feeder overloading area in the distribution system without operator intervention, thereby minimizing mistakes due to operator error.

• Journal of the Korean Operations Research and Management Science Society
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• v.40 no.3
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• pp.39-48
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• 2015

Even though ruin probability is a fundamental value to determine the insurance premium and policy, the complexity involved in computing its exact value forced us resort to an approximate method. In this paper, we first present an exact method to compute ruin probability under the assumption that the claim size has a GPH distribution, Then, for the arbitrary claim size distribution, we provide a method computing ruin probability quite accurately by approximating the distribution as a GPH. The validity of the proposed method demonstrated by a numerical example. The GPH approach seems to be valid for heavy-tailed claims as well as usual light-tailed claims.

• Journal of the Korean Statistical Society
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• v.33 no.2
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• pp.245-254
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• 2004

This paper derives a distribution function of the terminal value and running maximum of two-dimensional Brownian motion {X($\tau$) = (X$_1$($\tau$), X$_2$ ($\tau$))', $\tau$ 〉0}. One random variable of the joint distribution is the terminal time value, X$_1$ (T). The other random variable is the maximum of the Brownian motion {X$_2$($\tau$), $\tau$〉} between time s and time t. With this distribution function, this paper also derives an explicit pricing formula for an outside barrier option whose monitoring period starts at an arbitrary date and ends at another arbitrary date before maturity.