• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.252-252
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• 2007

$Al_2O_3-TiO_2$(AT)ceramics shows great promise as a dielectric material for millimeter-wave use. The sintering temperature of AT ceramics was approximately $1450^{\circ}C$ and decreased to $900^{\circ}C$ with the addition of BaCu(B2O5) (BCB) ceramic powder. The presence, of the liquid phase was responsible for the decrease of the sintering temperature. The liquid phase is considered to have a composition similar to the BaO-deficient BCB. The Q-value initially increased with the addition of BCB, but decreased considerably when a large amount of BCB was added, because of the presence of the liquid phase. Good microwave dielectric properties of $Q{\times}f\;=\;16,200\;GHz$, ${\varepsilon}_r\;=\;9$ and ${\tau}_f\;=\;-4\;ppm/^{\circ}C$ were obtained for the 20.0 mol% BCB-added AT ceramics sintered at $900^{\circ}C$ for 2 h.

• 대한수학회논문집
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• 제11권1호
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• pp.245-252
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• 1996

The relative Nielsen number N(f;X,A) was introduced in 1986. It gives us a better, and ideally sharp, lower bound for the minimum number MF[f;X,A] of fixed points in the homotopy class of the map $f;(X,A) \to (X,A)$. Similarly, we also can think about the Nielsen map $f:(X,A) \to (X,A)$. Similarly, we also can be think about the Nielsen root theory. In this paper, we introduce a relative root Nielsen number N(f;X,A,c) of $f:(X,A) \to (Y,B)$ and show some basic properties.

• Carbon letters
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• 제12권4호
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• pp.252-255
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• 2011

Carbon-based electric double-layer capacitors are being evaluated as potential energy-storage devices in an expanding number of applications. In this study, samples of carbon black (CB) treated at different temperatures ranging from $650^{\circ}C$ to $1100^{\circ}C$ were used as electrodes to improve the efficiency of a capacitor. The surface properties of the heat-treated CB samples were characterized by X-ray photoelectron spectroscopy and X-ray diffraction. The effect of the heat-treatment temperature on the electrochemical behaviors was investigated by cyclic voltammetry and in galvanostatic charge-discharge experiments. The experimental results showed that the crystallinity of the CBs increased as the heat-treatment temperature increased. In addition, the specific capacitance of the CBs was found to increase with the increase in the heat-treatment temperature. The maximum specific capacitance was 165 $F{\cdot}g-1$ for the CB sample treated at $1000^{\circ}C$.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2009년도 추계 학술발표
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• pp.170-171
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• 2009

• 대한수학회보
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• 제51권1호
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• pp.237-252
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• 2014

In this paper, we give a necessary and sufficient condition for the hyponormality of the block Toeplitz operators $T_{\Phi}$, where ${\Phi}$ = $F+G^*$, F(z), G(z) are some matrix valued polynomials on the vector valued Bergman space $L^2_a(\mathbb{D},\mathbb{C}^n)$. We also show some necessary conditions for the hyponormality of $T_{F+G^*}$ with $F+G^*{\in}h^{\infty}{\otimes}M_{n{\times}n}$ on $L^2_a(\mathbb{D},\mathbb{C}^n)$.

• 기본간호학회지
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• 제21권3호
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• pp.243-252
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• 2014

Purpose: The purpose of this study was to investigate diabetic knowledge, self-care behaviors, and HbA1c of patients with diabetic mellitus in public hospitals. Methods: Participants were 287 adult patients who had been diagnosed with diabetes in two public hospitals in Seoul. Collected data were analyzed using t-test, ANOVA, Pearson's correlation with the SPSS (PASW) 21.0 program. Results: For general characteristics of the participants, there were significant differences in the level of diabetic knowledge according to age (F=11.28, p<.001), educational level (F=11.07, p<.001), type of health insurance (F=9.38, p<.001), and monthly income (t=-4.58, p<.001) and in the self-care behaviors according to age (F=8.61, p<.001) and in HbA1c according to age (F=6.72, p=.001). As for disease related characteristics of the participants, significant differences were found for self-care behaviors according to education about diabetes (t=3.90, p<.001) and in HbA1c according to education about diabetes (t=3.26, p=.001) and current diabetic therapy methods (F=13.51, p<.001). The study results showed that there was no correlation between diabetic knowledge and self-care behavior, or between self-care behavior and HbA1c. Conclusion: Results indicate that when developing preliminary data on nursing intervention education programs on diabetes, increasing diabetic knowledge and self-care behaviors would help to improve blood glucose levels.

• 식물병연구
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• 제20권4호
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• pp.245-252
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• 2014

본 실험은 Fusarium oxysporum f. sp. cucumerinum에 의해 발생하는 오이 덩굴쪼김병의 효율적인 저항성 검정 방법을 확립하기 위하여 수행되었다. ITS와 TEF 유전자 염기서열 분석과 멜론, 참외, 오이 및 수박을 포함한 박과 작물에 대한 기주 특이성 분석을 통해 KR5 균주를 F. oxysporum f. sp. cucumerinum으로 동정하였다. 그리고 덩굴쪼김병균 KR5에 저항성 정도가 다른 오이 네 품종과 오이용 대목 두 품종을 선발하여 유묘의 생육 시기, 뿌리 상처, 접종원 농도 및 접종 후 재배 온도에 따라 이들 여섯 품종의 덩굴쪼김병 발생을 조사하였다. 저항성 품종의 덩굴쪼김병 발병도는 접종 후 재배 온도에 따라 차이를 나타냈으며, 저항성 품종들은 접종 후에 $20^{\circ}C$보다 $25^{\circ}C$나 $30^{\circ}C$에서 재배하였을 때 높은 저항성을 보였다. 그리고 유묘의 생육 시기 중 파종 후 7일된 유묘에 덩굴쪼김병균을 접종하였을 때 가장 큰 저항성과 감수성 차이를 나타내었다. 이상의 결과로부터 오이 덩굴쪼김병에 대한 저항성을 효과적으로 검정하는 방법으로 파종하고 7일 동안 재배한 유묘의 뿌리로부터 흙을 제거하고, 이들을 $1.0{\times}10^6-1.0{\times}10^7$ conidia/ml 농도의 F. oxysporum f. sp. cucumerinum 포자현탁액에 침지하여 접종한 후에 건전한 원예용 상토에 이식하고 $25^{\circ}C$ 생육상에서 3주간 재배하는 방법을 제안한다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.252-255
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• 1999

The effect of calcination temperature(1st and 2nd calcining at 110$0^{\circ}C$ , 120$0^{\circ}C$ and 130$0^{\circ}C$ respectively) on physical properties of BMNT Ceramics ware investigated. The optimum 1st and 2nd calcination temperature were 120$0^{\circ}C$ , and sintering temperature was 155$0^{\circ}C$. In this condition, the sintering density was 7.53 [g/㎤] and the dielectric constant, Q.f$_{0}$ and $\tau$$_{r}$ were 26, 80, 300[GHz] and +1.5[ppm/$^{\circ}C$] respectively in the microwave range.e.e.

• Journal of Animal Science and Technology
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• 제47권2호
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• pp.243-252
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• 2005

• 센서학회지
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• 제13권3호
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• pp.252-257
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• 2004

$Y_{2}O_{3}:Eu^{3+}$ thin films have been grown on $Al_{2}O_{3}$(0001) substrates by a pulsed laser deposition (PLD) method. The phosphor thin films were deposited at a substrate temperature of 500, 600, and $700^{\circ}C$ under the oxygen pressure of 100, 200, and 300 mTorr. The crystallinity, surface roughness and photoluminescence of the films are highly dependent on the substrate temperature and oxygen pressure. The films grown on $Al_{2}O_{3}$(0001) substrate even under the different substrate temperatures and oxygen pressures exhibited (222) preferred orientation. The luminescent spectra exhibited strong luminescence of ${^{5}D_{0}}-{^{7}F_{2}}$ transition within $Eu^{+3}$ peaking at 612 nm. The crystallinity and luminescence intensity of the films have been improved as the substrate temperature increasing. With increase of oxygen pressure from 50 to 300 mTorr, the crystallinity of the films has been uniformly decreased. The photoluminescence intensity and surface roughness have similar behaviors as a function of oxygen pressure. At 200 mTorr, both photoluminescence intensity and surface roughness show a maximum.