• Communications for Statistical Applications and Methods
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• v.3 no.2
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• pp.187-195
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• 1996

This paper deals with the stochastic comparisons of order statistics from independent but nonidentically distributed (i.n.i.d) variates. And we consider order statistics under positive dependence, negative dependence, and exchangeability.

• Journal of the Korean Society for Heat Treatment
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• v.24 no.6
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• pp.311-317
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• 2011

The effect of strain rate on the yield stress of an Al-Li alloy has been investigated at temperatures between 77 and 523 K and over the strain rate range from $1.77{\times}10^{-4}s^{-1}$ to $1.77{\times}10^{-2}s^{-1}$. At testing temperatures below 373 K, the yield stress is almost independent of strain rate at any aging stage. At testing temperatures above 373 K, the yield stress increases linearly with the logarithm of strain rate, and the strain rate dependence increases with increasing testing temperature. The yield stresses of under-aged alloy at temperatures between 373 and 473 K at high strain rates are greater than the yield stress at 77 K. For the alloy under-aged or aged nearly to its peak strength, the temperature range within which the positive temperature dependence of yield stress appears expands to the higher temperature side with increasing strain rate. The strain rate dependence of the yield stress is slightly negative at this aging stage. The yield stress of the over-aged alloy decreases monotonically with decreasing strain rate and with increasing testing temperature above 373 K. The modulus normalized yield stress is nearly constant at testing temperatures below 373 K at any strain rate investigated. And, strength depends largely both on the aging conditions and on the testing temperature. The peak positions in strength vs. aging time curves shift to the side of shorter aging time with increasing testing temperature. For the specimens aged nearly to the peak strength, the positive temperature dependence of yield stress is observed in the temperature range. The shift of peak positions in the aging curves are explained in terms of the positive temperature dependence of cutting stress and the negative temperature dependence of by-passing stress.

• Honam Mathematical Journal
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• v.36 no.3
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• pp.679-688
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• 2014

The notion of asymptotically negative dependence for collection of random variables is generalized to a Hilbert space and the almost sure convergence for these H-valued random variables is obtained. The result is also applied to a linear process generated by H-valued asymptotically negatively dependent random variables.

• Journal of applied mathematics & informatics
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• v.27 no.3_4
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• pp.885-893
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• 2009

In this paper we study the strong law of large numbers for weighted average of pairwise negatively quadrant dependent random variables. This result extends that of Jamison et al.(Convergence of weight averages of independent random variables Z. Wahrsch. Verw Gebiete(1965) 4 40-44) to the negative quadrant dependence.

• Asia-Pacific Journal of Business
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• v.15 no.1
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• pp.335-352
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• 2024

Purpose - Low fertility rate is a serious problem, and this study analyzes factors affecting total fertility rate using panel data from 16 metropolitan cities and provinces in Korea from 2000 to 2022. Design/methodology/approach - Estimating the SAR model considering the weak cross-sectional dependence that exists in variables related to the regional total fertility rate, and using the DKSE estimation method considering the strong cross-sectional dependence. Findings - Estimation results considering weak and strong cross-sectional dependence were similar, confirming the robustness of the results. Female labor force participation rate has a positive effect on total fertility rate, and employment rate has no effect. However, the interaction term is a negative (-) sign. Crude marriage rate has a positive effect on total fertility rate, and apartment price has a slightly positive effect. Environmental factor has no effect, and policy factor has a negative effect. Research implications or Originality - In order for an increase in the female labor force participation rate to lead to an increase in the total fertility rate, qualitative improvements in female employment must be made. Financial investment policies for childbirth must increase their effectiveness. The problem of low fertility rate requires not only population policy but also social, economic, cultural, environmental, and policy conditions to be considered.

• Current Optics and Photonics
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• v.2 no.3
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• pp.286-290
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• 2018

We investigated the dependence of the retardation dispersion on the polarization direction of ultraviolet (UV) light during the photopolymerization of self-organized smectic reactive mesogen (RM) molecules. RM retarder film that was photopolymerized with UV light linearly polarized parallel to the layer plane showed negative dispersion (ND) of retardation for a wide range of UV polymerization temperatures. On the other hand, film that was photopolymerized with unpolarized UV light showed negative dispersion in a narrow range of UV polymerization temperatures. With a certain UV polymerization temperature, the dispersion of retardation was converted from positive to negative, depending on the UV polarization.

• Korean Journal of Human Ecology
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• v.5 no.2
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• pp.131-143
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• 1996

The purpose of this study was to investigate clothing involvement and clothing behavior of women and to indentify the relationship between clothing behavior and clothing involvement. The data were analyzed using percentage, frequency, factor analysis, ANOVA, Scheffe test, t-test, and Multiple Regression. The results of the study were as follows: 1. Five dimensions of clothing involvement were derived by factor analysis such as fashion, interest pleasure, symbolism, and perceived buying risk. 2. There were significant relationships between clothing involvement dimensions and demographic characteristics such as age, educational background and family income level. Those who were younger and not married showed positive relationship among fashion, interest and pleasure of clothing involvement dimensions. Those who had higher educational background showed positive relationship with clothing involvement. Those who were empolyed showed higher clothing involvement with symbolism and perceived buying risk. 3. Age, marital status, and educational background showed important variables as factors that exert influence on clothing behavior: Those who were younger and not married attached importance to interest aesthetics, psychological dependence, and fashion. Those who were older and married attached importance to modesty and comfort. The more educated respondents were more concerned about interest aesthetics, symbolism, psychological dependence, and fashion. 4. The fashion of clothing involvement showed positive relationship in fashion, interest, symbolism, and psychological dependence of clothing behavior, and negative relationship in modesty and comfort. The interest of clothing involvement showed positive relationship in aesthetics and interest, and negative relationship in modesty and comfort of clothing behavior. The pleasure of clothing involvement showed positive relationship in psychological dependence, management, interest, and pleasure of clothing behavior. The symbolism of clothing involvement showed positive relationship in symbolism, modesty, conformity, psychological dependence, and fashion of clothing behavior. The perceived buying risk of clothing involvement showed positive relationship in management, conformity, and comfort and negative relationship in symbolism and fashion of clothing behavior.

• Journal of applied mathematics & informatics
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• v.6 no.3
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• pp.959-968
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• 1999

In this paper we are obtained new results for bivariate pro-cesses which help us to tell the dependent structure among hitting times of the processes. We are proposed both dependence properties and the-oretical results among the processes and certain kinds of dependence properties when we are imposed on processes are reflected as analo-gous properties of corresponding hitting times. Finlly we are given some examples to illustrate these concepts.

• Journal of applied mathematics & informatics
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• v.29 no.1_2
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• pp.201-210
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• 2011

In this paper, we obtain the H$\`{a}$jeck-R$\`{e}$nyi type inequality and the strong law of large numbers for asymptotically linear negative quadrant dependent random variables by using this inequality. We also give the strong law of large numbers for the linear process under asymptotically linear negative quadrant dependence assumption.

• The Journal of the Korea Contents Association
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• v.14 no.2
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• pp.355-363
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• 2014

The purpose of this study is to find out the effect of using cellular phone dependence of middle school student based on Agnew's GST. A total of 2,151 questionnaires were used to Korean Children and Youth Panel Survey(KCYPS)2010. Analytical methods of Structural Equation Model(SEM) was verified by AMOS 21.0 Ver. The results were the following. Firstly, The fit of definitive model was $X^2=1398.997$, df=144, GFI=.937, NNFI(TLI)=.902, CFI=.918, RMSEA=.061. Model was proper to verify the use of cellular phone dependence of adolescents. Secondly, The strain factors of middle school student presented statistically significant positive effect to make negative life satisfaction. Finally, The negative life satisfaction of middle school student presented statistically significant positive effect to the use of cellular phone dependence of middle school student. We need to provide as basic data for developing cellular phone dependence intervention programs.