• Journal of the Korean Mathematical Society
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• v.33 no.1
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• pp.205-216
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• 1996

In [13], Ptak and Vrbova proved that if T is a bounded normal operator T on a complex Hilbert space H, then the ranges of the spectral projections can be represented in the form $$ \varepsilon(F)H = \bigcap_{\lambda\notinF} (T - \lambda I) H for all closed subsets F of C, $$ where $\varepsilon$ denotes the spectral measure associated with T.

• Journal of the Chungcheong Mathematical Society
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• v.3 no.1
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• pp.33-40
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• 1990

We prove that if a $weak^*$-measurable function f defined on a finite measure space into a dual Banach space is separable-like, then for every measurable set E, the $weak^*$ core of f over E is the $weak^*$ convex closed hull of the $weak^*$ essential range of f over E.

• Proceedings of the KIEE Conference
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• 1998.11a
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• pp.100-102
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• 1998

This paper presents technique to control blower at constant air volume rate using V/F Control. Especially, this control method have not pressure sensors to measure because of using torque-speed relation based on the fan laws. Therefore, this technique is very simple and practical.

• Bulletin of the Korean Mathematical Society
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• v.56 no.3
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• pp.801-813
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• 2019

In this paper, using the Baire category theorem we investigate the Hyers-Ulam stability problem of pexiderized Jensen functional equation $$2f(\frac{x+y}{2})-g(x)-h(y)=0$$ and pexiderized Jensen type functional equations $$f(x+y)+g(x-y)-2h(x)=0,\\f(x+y)-g(x-y)-2h(y)=0$$ on a set of Lebesgue measure zero. As a consequence, we obtain asymptotic behaviors of the functional equations.

• Communications for Statistical Applications and Methods
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• v.15 no.2
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• pp.147-159
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• 2008

We consider using ranked set sampling methods to draw inference about the three well-known measures of overlap, namely Matusita's measure $\rho$, Morisita's measure $\lambda$ and Weitzman's measure $\Delta$. Two exponential populations with different means are considered. Due to the difficulties of calculating the precision or the bias of the resulting estimators of overlap measures, because there are no closed-form exact formulas for their variances and their exact sampling distributions, Monte Carlo evaluations are used. Confidence intervals for those measures are also constructed via the bootstrap method and Taylor series approximation.

• Korean Journal of Mathematics
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• v.27 no.2
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• pp.437-444
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• 2019

For c > -1, let ${\nu}_c$ denote a weighted radial measure on ${\mathbb{C}}$ normalized so that ${\nu}_c(D)=1$. For $c_1,c_2>-1$ and $f{\in}L^1(D^2,\;{\nu}_{c_1}{\times}{\nu}_{c_2})$, we define the weighted Berezin transform $B_{c_1,c_2}f$ on $D^2$ by $$(B_{c_1,c_2})f(z,w)={\displaystyle{\smashmargin2{\int\nolimits_D}{\int\nolimits_D}}}f({\varphi}_z(x),\;{\varphi}_w(y))\;d{\nu}_{c_1}(x)d{\upsilon}_{c_2}(y)$$. This paper is about the space $M^p_{c_1,c_2}$ of function $f{\in}L^p(D^2,\;{\nu}_{c_1}{\times}{\nu}_{c_2})$ ) satisfying $B_{c_1,c_2}f=f$ for $1{\leq}p<{\infty}$. We find the identity operator on $M^p_{c_1,c_2}$ by using invariant Laplacians and we characterize some special type of functions in $M^p_{c_1,c_2}$.

• Research in Community and Public Health Nursing
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• v.13 no.1
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• pp.124-136
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• 2002

In the present study we have attempted to explore the relationship between family support that young people receive and the level of Ego Identity that they develop. We started the present study with the purpose of providing parish nurses with some basic data for nursing intervention for family and school nursing, as well as for community health care. We conducted the present study during the period of October 15, 2001 through November 5, 2001. The objects of this study were Inmunge High School students chosen from a school in Daejon. The subject students were selected randomly from each grade in that school. The numbers of subjects selected were 120 boys and 113 girls (total: 233). The research tool that we used to measure perceived family support received by students was one that Ga Eon Lee revised for high school students on the basis of Cobb's theory. To measure the subject students' Ego Identity level we used Bong Yon Sho's 'Ego Identity Scale', that he revised from Dignan's 'Ego Identity Scale' for Korean high school students. Data were analyzed with SPSS Win 10.0 program using statistics of frequencies, percentage, t-test, ANOVA, and Pearson correlation coefficient. The findings of the present study indicate that: 1) The mean of family support that the subject students feel that they received was 39.99 on the family support scale, and the mean of the students on the Ego Identity scale was 186.16. 2) The support that the subjects received from their own family had a statistically significant correlation with their Ego Identity (r=.93, p=.00). 3) Various factors had a significant correlation with the level of family support perceived by the subjects: the subject's grade (F=3.35, p=.04), the subject's religion (t=6.39, p=.00), the family's economic situation (F=9.14, p=.00), the birth order (F=27.61. p=.00), the father's education (F=23.17, p=.00), the mother's education (F=28.70, p=.00), parental relationship (F=2657.03, p=.00), and the structure of the family (F=-9.65. p=.00). 4) Various factors had a significant correlation with the level of the subject's Ego Identity: the subjects religion (t=6.20, p=.00), the family's economic situation (F=12.56, p=.00), the birth order (F=22.85, p=.00), the father's education (F=10.37, p=.00), the mother's education (F=20.69, p=.00), parental relationship (F=938.73. p=.00), and the structure of the family (F=-8.74, p=.00). 5) Analyzing sources of support within the family, family members whom the subjects trust most (F=3.08, p=.03) and family members to whom they talk most (F=5.85, p=.00) showed the most significant differences. Analyzing sources of support within the family that affect the level of the subjects' Ego Identity, family members whom the subjects trust most (F=3.30. p=.02) and family members to whom they talk most also showed the most significant differences.

• The Korean Journal of Applied Statistics
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• v.32 no.2
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• pp.291-300
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• 2019

This study investigates the characteristics of evaluation measures for classification models on a binary response variable in order to evaluate their suitability for use. Six measures are considered: Accuracy, Sensitivity, Specificity, Precision, F-measure, and the Heidke's skill score (HSS). Evaluation measures are reformulated using x(ratio of actually 1), y(ratio predicted by 1), z(ratio of both actual and predicted by 1) from the confusion matrix. We suggest two necessary conditions to assess the suitability of the evaluation measures. The first condition is that the measure function is constant for x and y in the case of a random model. The second condition is that the measure function is increasing for z and decreasing for x and y. Since only HSS satisfies the two conditions, that is always appropriate as an evaluation measure for the classification model on the binary response variable, and the other measures should be used within a limited range.

• Transactions on Electrical and Electronic Materials
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• v.2 no.1
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• pp.16-21
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• 2001

A new technique to measure low level capacitance variations of a gyroscope is proposed. It is based on the improved CVC(capacitance to voltage converter) biased by a d.c. current source and the peak detector without any low pass filter. This setup of the measurement system makes it possible to provide higher speed of measurement and wide operation range. The d,c, drift of the conventional CVC and stray capacitances are automatically compensated. Key parameters that affect the performance of the measurement system are illustrated and computer simulation results are presented. The demonstrated measurement system for micromachined gyroscope applications shows a linearity of 0.99972 and a resolution of 0.67fF from 10 fF to 120 fF at 10 kHz.

• Journal of the Chungcheong Mathematical Society
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• v.8 no.1
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• pp.161-166
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• 1995

Let (${\Omega}$, ${\Sigma}$, ${\mu}$) be a finite perfect measure space, and let $f:{\Omega}{\rightarrow}X$ be strongly measurable. f is Pettis integrable if and only if there is a sequence ($f_n$) of Pettis integrable functions from ${\Omega}$ into X such that (a) there is a positive increasing function ${\phi}$ defined on [0, ${\infty}$) such that ${\lim}_{t{\rightarrow}{\infty}}\frac{{\phi}(t)}{t}={\infty}$ and sup $f_{\Omega}{\phi}({\mid}x^*f_n{\mid})d{\mu}$ < ${\infty}$ for each $x^*{\in}B_{X*}$,$n{\in}N$, and (b) for each $x^*{\in}X^*$, $lim_{n{\rightarrow}{\infty}}x^*f_n=x^*fa.e.$.