• Proceedings of the KWS Conference
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• 2009.11a
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• pp.94-94
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• 2009

The purpose of this study is to identify the principal factor controlling transverse residual stress at the weldment for joining unit hull blocks. In order to do it, the comprehensive FE analyses were carried out to evaluate the effect of distance between fillet and butt weldments, in-plane and out-of-plane restraint degree on the amount and distribution of transverse residual stress in way of the weldments between unit hull blocks. In accordance with FEA results, principal factor controlling the amount of transverse residual stress at the weldments was identified as in-plane restraint degree of butt weldment for unit blocks. The effect of other variables on the transverse residual stress was very small relatively. Based on the results, it can be concluded that the proper distance between fillet weldment for stiffener and butt weldment for joining unit blocks should be determined in consideration of in-plane restraint intensity of butt weldments.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.04a
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• pp.59-62
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• 2000

In this study, the distribution of the effective modulus was investigated statistically Plain weave structures were modeled with random stacking phase shift angles and the effective modulus was calculated by the unit cell analysis. The analysis results indicated that the effect of random phase shift angles was significant on the modulus distribution. As the number of layers increased, the coefficient of variation decreased and higher degree of homogeneity was attained.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.758-763
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• 2006

Statistical concepts and methods are routinely utilized in a number of design and management problems in engineering hydrology. This is because most of hydrological processes have some degree of randomness and uncertainty. Thus, the concepts of risk and uncertainty are commonly utilized for designing and evaluating hydraulic structures such as spillways and dikes. Therefore, in this study, uncertainty analysis considering the variance of design floods is performed to evaluate the uncertainty of the hydrologic risk of flood related hydraulic structures using frequency analysis.

• Journal of the Korean Statistical Society
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• v.23 no.1
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• pp.103-114
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• 1994

For a $2 \times 2$ factorial design without the restriction of a linear model or without regard to error terms having homoscedasticity, under the null hypothesis of no interaction we can have the rank transformed F statistic for interaction converge in distribution to a chi-squared random variable with one degree of random if and only if there is only main effect.

• Bulletin of the Korean Mathematical Society
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• v.41 no.3
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• pp.451-456
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• 2004

Given a function on a scheme over a finite field, we can count the number of rational points of the scheme having the same values. We show that if the function, viewed as a morphism to the affine line, is proper and its higher direct image sheaves are tamely ramified at the infinity then the values are uniformly distributed up to some degree.

• Journal of Distribution Research
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• v.4 no.1
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• pp.31-49
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• 1999

The present paper discusses the current status of outsourcing of service encounter in department stores. We attempt to find if there is any significant relationship between outsourcing motive and business performance. The 30 department stores under analysis show that they vary in the degree to which they appreciate the necessity of outsourcing and also the which they employ outsourcing. It is also found that firm size influences the portion of outsourcing. The two main motives of outsourcing seem to be (i) cost saving and (ⅱ) better customer satisfaction. We find that the latter plays a more important role. However, there seems to be no significant connection between outsourcing and performance and between motives of outsourcing and performance.

• Journal of the Korean Society of Safety
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• v.22 no.3 s.81
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• pp.28-33
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• 2007

Often Regular Measurement Target 32 Spots which are distributed at Seo-gu in Incheon Metropolitan and Odour Emission Target 100 Factories based on the task instruction of Ministry of Environment in Korea were selected by considering to atmosphere phenomena and regional characteristics etc. This paper aims at building the Decreasing Prediction System of Odour which is capable of comparing and examining the concentration distribution by odour compounds, the distribution maps of odour diffusion and the contribution degree of sphere of influence, which is discharged from these above spots and factories.

• Communications for Statistical Applications and Methods
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• v.13 no.2
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• pp.219-231
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• 2006

When the correlation of two random variables is weak, the value of one variable can not be used effectively to predict the other. Even when most of the values are overlapped, it is difficult to find a linear relationship. In this paper, we propose two graphical methods of representing the measures of correlation and independence between two random variables. The first method is used to represent their degree of correlation, and the other is used to represent their independence. Both of these methods are based on the cumulative distribution functions defined in this work.

• Journal of Distribution Science
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• v.19 no.4
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• pp.53-60
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• 2021

Purpose: This study focuses on exploring ways to improve the distribution method of shrimp farming so that it is eco-friendly and increases the distribution of shrimp. Research design, data and methodology: The experimental device installed in a biofloc shrimp culture in one area tested 10 times. Complex odor, concentration of H2S, water quality improvement effected by decomposition of organic substances, and degree of microbial activation measured. The data of the experimental results verified using the T-test technique, and the p value was determined based on the significance probability of 0.05. Results: This experimental device was effective in reducing odor and hydrogen sulfide in shrimp farms. With the improvement of water quality, dissolved oxygen increased due to the microbubble and cavitation action of air ejector and ultrasonic waves. In addition, the cultured microorganisms in the cultured water treated by the experimental device were remarkably proliferated compared to the raw water. Conclusions: The biofloc distribution method has a significant effect on improving water quality and reducing odor substances and will become a new eco-friendly and efficient distribution method for shrimp farming in the future.

• Journal of Distribution Science
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• v.13 no.10
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• pp.135-142
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• 2015

Purpose - Following the speedy development of the smart phone industry, tourism companies started to increase their brand recognition and sales volume by adopting mobile applications. However, applications for tourism industries are still insignificant. This study tries to analyze empirical evidence from Korean and Chinese consumers who have used mobile tour applications. By using an expansion of the technology acceptance model (TAM), this study will find what factors have effects on user intention for mobile tour applications. The findings will be helpful for the development of mobile tour applications and the tourism industries. Research design, data, and methodology - This study uses the TAM, which was presented by Davis in 1989. This study uses consumer acceptance level, consumer choice attitude, and use intention as the basic variables to fit to the TAM, and adopts choice content quality, brand value, and usage motivation as additional variables to analyze. This study has developed several hypotheses and collected data from 620 users who used mobile applications for tourism during April 1 to April 30, 2015. A total of 612 valid questionnaires were collected and used in the data analysis. The data was analyzed with structural equation modeling using SPSS Win/pc and Amos 22.0. Results - The findings can be summarized as follows: First, the content quality affects the consumer acceptance degree and choice attitude. Second, the brand value has a directly positive effect on the consumer acceptance degree and choice attitude. It is clear that the content quality and brand value play important roles in raising consumer acceptance and choice attitude. Third, usage motivation has no effect on the consumer acceptance degree and choice attitude. Fourth, the acceptance degree does not have any effect on the consumer choice attitude. Fifth, the acceptance degree affects the use intention. Last, the consumer choice attitude affects the use intentions. This indicates that consumer acceptance and choice attitude must both be achieved to induce use intention among consumers. Finally, the effects of the mobile tour application content quality and brand value on consumer acceptance degree and choice attitude were confirmed. Additionally, the effects of the consumer acceptance degree and choice attitude on use intentions were analyzed. Conclusion - It is not meaningful for tourism marketing to launch tour applications in the mobile market without understanding tourism consumer characteristics. When developing mobile tour applications, companies should focus on the characters of consumer choice attitudes as high quality, high brand value, usefulness, and ease of mobile tour applications. This study has limitations in that it did not consider negative factors such as perceived risks or analyze whether there are differences between Korean and Chinese consumers. In the future, we will consider equipping the same mobile tour applications commonly used by both Korean and Chinese consumers, and then examine negative factors as well as the differences in mobile tour applications between Korean and Chinese consumers.