• 대한수학회논문집
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• 제18권3호
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• pp.521-532
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• 2003

In this paper, we introduce the notions of ($T_{i},\;T_{j}$)-fuzzy (r, s)-preopen sets and fuzzy pairwise (r, s)-precontinuous mappings in smooth bitopological spaces and then we investigate some of their characteristic properties.

• 대한수학회보
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• 제53권2호
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• pp.365-371
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• 2016

Let f be a transcendental meromorphic function in the complex plane $\mathbb{C}$, and a be a nonzero constant. We give a quantitative estimate of the characteristic function T(r, f) in terms of $N(r,1/(f^2(f^{\prime})^n-a))$, which states as following inequality, for positive integers $n{\geq}2$, $$T(r,f){\leq}\(3+{\frac{6}{n-1}}\)N\(r,{\frac{1}{af^2(f^{\prime})^n-1}}\)+S(r,f)$$.

• 대한수학회보
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• 제57권3호
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• pp.709-737
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• 2020

Let R be a prime ring of characteristic different from 2. Suppose that F, G, H and T are generalized derivations of R. Let U be the Utumi quotient ring of R and C be the center of U, called the extended centroid of R and let f(x₁, …, x_n) be a non central multilinear polynomial over C. If F(f(r₁, …, r_n))G(f(r₁, …, r_n)) - f(r₁, …, r_n)T(f(r₁, …, r_n)) = H(f(r₁, …, r_n)²) for all r₁, …, r_n ∈ R, then we describe all possible forms of F, G, H and T.

• 한국전자파학회논문지
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• 제19권8호
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• pp.940-945
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• 2008

본 논문에서는 능동 위상 배열 레이다 시스템에 적용 가능한 브릭형 구조의 능동 송수신 모듈을 설계 및 제작하였다. 제안한 브릭형 구조의 능동 송수신 모듈은 MCM(Multi-Chip Module) 형태이며, 타일형 능동 송수신 모듈에 적용할 수 있도록 하기 위하여 캐비티 구조와 주요 특성을 만족하도록 설계하였다. 제작한 브릭형 능동 송수신 모듈의 시험을 통하여 목표로 한 전기적 특성을 만족함을 확인하였으며, 능동 위상 배열 레이다에 운용 가능성을 확인하였다.

• 호남수학학술지
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• 제27권3호
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• pp.399-404
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• 2005

Let M be a finite commutative nilpotent algebra over a perfect field k of prime characteristic p and let $M^p$ be the sub-algebra of M generated by $x^p$, $x{\in}M$. Eggert[3] conjectures that $dim_kM{\geq}pdim_kM^p$. In this paper, we show that the conjecture holds for $M=R^+/I$, where $R=k[X_1,\;X_2,\;{\cdots},\;X_t]$ is a polynomial ring with indeterminates $X_1,\;X_2,\;{\cdots},\;X_t$ over k and $R^+$ is the maximal ideal of R generated by $X_1,\;X_2,{\cdots},\;X_t$ and I is a monomial ideal of R containing $X_1^{n_1+1},\;X_2^{n_2+1},\;{\cdots},\;X_t^{n_t+1}$ ($n_i{\geq}0$ for all i).

• 성인간호학회지
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• 제14권1호
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• pp.102-113
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• 2002

Purpose: This study was designed to identify the relationship between self reported climacteric symptoms, self concept and depression in middle aged women. Method: Data were collected through self-reported questionaires which were constructed to include a climacteric symptoms, self-concept and depression of middle-aged women scale. The subjects for this study were 102 women between 40-59 years of age living in P city. The data were analyzed by descriptive statistics, t-test, ANOVA, Pearson Correlation Coefficient. Results: The results obtained from this study were as follows : 1) The relationship between self reported climacteric symptoms and self concept was statistically significant with a negative correlation (r=-0.4862, P0.001). The relationship between self reported climacteric symptoms and depression had a statistically significant positive correlation (r=0.5393, P<0.001). The Relationship between self-concept and depression had a statistically significant negative correlation (r=-0.3769, P<0.001). 2) General characteristic variables significantly related to self reported climacteric symptoms were age (F=3.13, P<0.05) and frequency of pregnancy (F=3.24, P<0.05). General characteristic variables significantly related to frequency of self-concept were age (F=3.13, P<0.05), education level (F=2.97, P<0.05) and occupation (t=1.84, P<0.05). General characteristic variables significantly related to depression were age (F=3.12, P<0.05) and number of children (t=3.59, P<0.05). 3) The obstetrical characteristic variable significantly related to self-reported climacteric symptoms was the frequency of pregnancy (t=3.24, P<0.05). Conclusion: This study shows possible implications for nursing intervention for middle-aged women's health to prevent and relieve climacteric symptoms.

• 동력기계공학회지
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• 제18권6호
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• pp.126-132
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• 2014

The P-T characteristics of mixed refrigerant in thermostatic expansion valve sensing bulb were studied using R-134a and R-410A refrigerant. The characteristics of mixed refrigerant were investigated according to pressure variation and the variation of composition ratio of R-134A and R-410A in the temperature range of $-15^{\circ}C{\sim}15^{\circ}C$. The Thermodynamic characteristic values of the mixed refrigerants were identified using the characteristic value analysis program of mixed refrigerant(Refrop v9.0, NIST). The P-T characteristics in the case of the mixing ratio of 90:10 for R-410A and R-134A were the same result as R-22. And the physical properties showed similar results with R-22. The Maximum operating pressure(MOP) of mixed refrigerant showed a tendency to decrease with decreasing the mixing ratio of additive gases($N_2$ or He) gases. The characteristics in the case of the mixing ratio of 80:1 for mixed refrigerant and additive gases were the similar result as Reference refrigerant.(R-22 MOP, Sporlan company) In addition $N_2$ and He, both showed the same results. It was able to confirm that a MOP on the thermostatic expansion valve sensing bulb can be maintained by adjusting the mixing ratio of mixed refrigerant gases and additive gases.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 12th Asian Congress of Fluid Mechanics
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• pp.39.5-40
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• 2008

• Transactions on Electrical and Electronic Materials
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• 제3권2호
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• pp.20-23
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• 2002

Temperature (T) dependence of the sheet resistance (R$\_$$\square$/) has been investigated an the c-axis oriented thin films of the (Bi2212/Bi2201) mixed crystal with different molar fractions. The R$\_$$\square$/-T superconducting characteristic deteriorated with reduction of the Bi2212 fraction, and almost disappears at 48 mol% where a superconductor-to-insulator transition too k place, with the resistance on the normal state, R$\_$N/, reaching 4.1 kΩka at 80 K. This R$\_$$\square$/ value is close to the universal quantum number, h/(2e)$_2$≡ 6.5 kΩ predicted by the Kosterlitz-Thouless (KT) transition theory. The R$\_$$\square$/-T characteristics of the 48 mol% thin film can be elucidated as a competitive process of KT transition brought about by charge or vortex in the two-dimensional layer structure.

• 한국전자파학회논문지
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• 제22권3호
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• pp.389-398
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• 2011

본 논문에서는 Ka 대역 위상 배열 레이더용 송수신(T/R: Transmit/Receive) 모듈의 설계 및 제작을 보였다. Ka 대역 송수신 모듈 구성 시 Ka 대역의 특수성을 고려하여 5비트(bit) 위상천이기와 5 비트 30 dB 디지털 가변감쇠기를 송수신 공통으로 사용하였으며, 서큘레이터는 T/R 모듈 외부에 부착되는 형태로 구성하였다. 단위 안테나 당 송신 출력은 1 W 이상 잡음 지수는 8 dB 미만으로 설정하였으며, 설계된 T/R 모듈의 RF부의 크기는 $5\;mm{\times}4\;mm{\times}57\;mm$로 소형화를 달성하였다. 설계된 T/R 모듈을 구현하기 위하여 T/R 모듈에 소요되는 개별 MMIC 검증 후 단위 T/R 모듈을 검증하는 방법을 사용하였다. 제작된 T/R 모듈은 설계 시 예측한 바와 같이 단위 T/R 모듈의 입력 5 dBm에서 출력 30 dBm 이상을 보였으며, 수신부는 잡음 지수 8 dB 미만, 이득 20 dB 이상을 얻었다.