• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.4
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• pp.136-145
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• 1998

This paper describes the FFT and coefficient analysis of vibration signals for preventive diagnosis of a mold transformer at normal and abnormal state. Varying applied voltage, loading current and temperature as control variables for he experiment, measurement variables such as magnitude of vibration signals, frequency spectrum and time series coefficient were analyzed. The vibration signals by variation of control variables were measured by acceleration sensor adhered on the surface of winding and core, and measurement variables were calculated using dat acquisition system. After analyzing the normal state, the structural distortion was also simulated. The vibration signals at abnormal state were measured by the same control variables variation as the normal state. As a result, vibration signals between normal and abnormal state could be distinguished by comparison of the perpendicular and horizontal vibration signal.

• The Journal of Korean Society for School & Community Health Education
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• v.24 no.3
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• pp.51-63
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• 2023

Objectives: This study aims to examine factors affecting depression of Older Adults by using the data of the elderly survey conducted by the Korea Institute of Health and Social Affairs in 2020. Methods: The total sample was 4,777 people aged over 65 years old. In this study, sociodemographic variables, information devices'use behavior and discomfort variables were input to examine the effect on depression. The data was analyzed with t²-test, ANOVA and hierarchical regression by SPSS statistic program. Results: First, use behavior and discomfort of information devices and depression were significantly different by sociodemographic variables(sex, age, level of education, marital status). Secondly, regression analysis showed that age and level of education affected an influence on depression in Model 1, which analyzed only sociodemographic variables. However, Model 2, which analyzed devices' use behavior and discomfort variables at the same time, showed that they affected depression. Conclusions: It was suggested to develop customized health education and mental health promotion were needed to reduce depression in the elderly.

• Journal of the Korean Society of Costume
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• v.38
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• pp.323-336
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• 1998

The purpose of this study was to classify the contents of self-image of college men and to investigate how clothing behavior was influenced by self-image, age, major, and the expenses of clothing. Samples were 342 male students of univer-sity in Seoul. Results of this study were following : 1. Four factors of self-image derived by factor analysis : F. 1‘mature-unmatured’;F. 2‘characteristic-ordinary’; F. 3‘conservative-open’; F. 4‘dominant-submissive’.2. 5 variables of clothing behavior were influenced by real self-image. Fashion was influenced by characteristic, open, dominant image, and the expenses of clothing. The ex-planatory power of the 4 variables was 29.3%. Aesthetics was influenced by characteristic, submissive, conservative image, the expenses of clothing, and age(R2=28.7%). Modesty was influenced by conservative and ordinary im-age(R2=6.5%). Coformity was influenced by ordinary image and the expenses of clothing (R2=5.7%). Comfort was influenced by dominant image and age(R2=5.3%). 3. 5 variables of clothing behavior were influenced by ideal self-image. Fashion was influenced by unmatured, characteristic, sub-missive image, and the expenses of clothing (R2=28.9%). Aesthetics was influenced by characteristic image, the expenses of clothing, and age(R2=23.5%). Modesty was influenced by conservative, mature, and ordinary image (R2=8.3%). Coformity was influenced by ordinary image(R2=1.9%). Comfort was influenced by mature image and age(R2=5.6%). The findings indicated that self-image had a significant effect on fashion and aesthetics, and characteristic image and conservative image were important variables that affected clothing behavior of college men.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.696-700
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• 1998

Fuzzy random variables with piecewise linear membership functions are introduced from a practical viewpoint. The estimation of the expected values of these fuzzy random variables is also discussed and statistical application is denonstratied by using a real data set.

• Journal of applied mathematics & informatics
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• v.34 no.3_4
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• pp.355-357
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• 2016

Recently, some results of Blackwell's Theorem in which interarrival times are characterized as fuzzy variables under t-norm-based fuzzy operations are discussed by Hong. However, these results are invalid. In this note, we give counter examples of these results.

• Korean Journal of Mathematics
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• v.16 no.4
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• pp.537-543
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• 2008

Guan and Li [2] obtained SLLN for weighted sums of level-wise independent fuzzy random variables. In this paper, a generalization of Guan and Li [2] is obtained by using the Skorokhod metric on F(R).

• Journal of the Chungcheong Mathematical Society
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• v.33 no.1
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• pp.133-146
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• 2020

In this paper, we established the complete moment convergence for sequences of m-pairwise negatively quadrant dependent random variables which are weakly upper bounded by a random variable X.

• Journal of Digital Convergence
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• v.6 no.4
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• pp.157-163
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• 2008

Despite the increase internet use rate, there still appears a big difference in web usage rates depending on demographic variables, web usage environment variables. This study aimed to improve our understanding of perceived usage, attitude, affected factors related Web usage for schoolwork and research. This result will facilitate further understanding of perceived usage, attitude, affected factors related Web usage, thereby enabling researchers, practitioners, and policy makers to better design appropriate strategies to promote the Web usage.

• Journal of applied mathematics & informatics
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• v.29 no.5_6
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• pp.1351-1361
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• 2011

We in this paper study the complete convergence and almost surely convergence for arrays of rowwise pairwise negatively dependent(ND) random variables (r.${\upsilon}$.'s) which are dominated randomly by some random variables and obtain a result dealing with complete convergence of linear processes.

• Communications of the Korean Mathematical Society
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• v.18 no.3
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• pp.551-558
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• 2003

In this paper we Obtain the Hajeck-Renyi type inequality for the asymptotically almost negatively associated(AANA) random variables and extend some results for negatively associated random variables to the AANA case by applying this inequality.