• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.271-272
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• 2012

Bulk Metallic Glasses (BMGs or amorphous alloy) exhibit high strength and good corrosion resistance. Applications of thin films and micro parts of BMGs have been used a lot since its inception in the research of BMGs. However, Application and fabrication of BMGs are limited to make structural materials. Thin films of BMGs which is sputtered on the surface of structural materials by sputtering process is used to improve limits about application of BMGs. In order to investigate the difference of properties between designed alloys and thin films, we identified that thin films deposited on the surface that have the characteristic of the amorphous films and the composition of designed alloys. Zr-Cu (Cu=30, 35, 38, 40, 50 at.%) and Zr-Cu-Al (Al=10 at.% fixed, Cu=26, 30, 34, 38 at.%) alloys were fabricated with Zr (99.7% purity), Cu (99.997% purity), and Al (99.99% purity) as melting 5 times by arc melting method before rods 2mm in diameter was manufactured. In order to analyze GFA (Glass Forming Ability), rods were observed by Optical Microscopy and SEM and $T_g$, $T_x$, ($T_x$ is crystallization temperature and $T_g$ is the glass transition temperature) and Tm were measured by DTA and DSC. Powder was manufactured by Gas Atomizer and target was sintered using powder in large supercooled liquid region ($=T_x-T_g$) by SPS(Spark Plasma Sintering). Amorphous foil was prepared by RSP process with 5 gram alloy button. The composition of the foil and sputtered thin film was analyzed by EDS and EPMA. In the result of DSC curve, binary alloys ($Zr_{62}Cu_{38}$, $Zr_{60}Cu_{40}$, $Zr_{50}Cu_{50}$) and ternary alloys ($Zr_{64}Al_{10}Cu_{26}$, $Zr_{56}Al_{10}Cu_{34}$, $Zr_{52}Al_{10}Cu_{38}$) have $T_g$ except for $Zr_{70}Cu_{30}$ and $Zr_{60}Al_{10}Cu_{30}$. The compositions with $T_g$ made into powders. Figure shows XRD data of thin film showed similar hollow peak.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.77.3-77
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• 2002

In this paper, the algorithm for detecting the transient change of ST-segment and the device for measuring ECG from patient without restriction of activity are introduced. ST-segment elevation and depression is considered as the main characteristic in diagnosis of myocardial ischemia, but the change of pattern is also important. To consider all of the former and the latter, we used polynomial approximation for diagnosis of ECG. The feature points(R, S and T are detected through the signal processing processes including wavelet transform, and then R-S and S-T are approximated to polynomial. This method allows comparison of two signals that have different sampling time or different numbers of...

• 호남수학학술지
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• 제36권4호
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• pp.805-812
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• 2014

For unit tangent sphere bundles $T_1M$ with the standard contact metric structure (${\eta},\bar{g},{\phi},{\xi}$), we have two fundamental operators that is, $h=\frac{1}{2}{\pounds}_{\xi}{\phi}$ and ${\ell}=\bar{R}({\cdot},{\xi}){\xi}$, where ${\pounds}_{\xi}$ denotes Lie differentiation for the Reeb vector field ${\xi}$ and $\bar{R}$ denotes the Riemmannian curvature tensor of $T_1M$. In this paper, we study the Reeb ow invariancy of the corresponding (0, 2)-tensor fields H and L of h and ${\ell}$, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.537-538
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• 2006

BSCCO thin films have been fabricated by epitaxy growth at an ultra-low growth rate. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was varied between 650 and $720^{\circ}C$ and the highly condensed ozone gas pressure ($PO_3$) in vacuum chamber was varied between $2.0{\times}10^{-6}$ and $2.3{\times}10^{-5}\;Torr$.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.653-653
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• 2013

In this study, ITO extended gate reduced graphene oxide field effect transistor (rGO FET) was demonstrated as a transducer for a proton sensing application. In this structure, the sensing area is isolated from the active area of the device. Therefore, it is easy to deposit or modify the sensing area without affecting on the device performance. In this case, the ITO extended gate was used as a gate electrode as well as a proton sensing material. The proton sensing properties based on the rGO FET transducer were analyzed. The rGO FET device showed a high stability in the air ambient with a TTC encapsulation layer for months. The device showed an ambipolar characteristic with the Dirac point shift with varying the pH solutions. The sensing characteristics have offered the potential for the ion sensing application.

• Transactions on Electrical and Electronic Materials
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• 제1권1호
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• pp.26-31
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• 2000

The ~1540 nm $^4$ $I_{13}$ 2/ longrightarro $w^4$ $I_{15}$ 2/ emissions of E $r^{3+}$ in Er-implanted GaN annealed at temperatures in the 400 to 100$0^{\circ}C$ range were investigated to gain a better understanding of the formation and dissociation processes of the various E $r^{3+}$ sites and the recovery of damage caused by the implantation with increasing annealing temperature ( $T_{A}$).The monotonic increase in the intensity of the broad defect photoluminescence(PL) bands with incresing $T_{A}$ proves that these are stable radiative recombination centers introduced by the implantation and annealing process. Theser centers cannot be attributed to implantation-induced damage that is removed by post-implantation annealing. Selective wavelength pumpling of PL spectra at 6K reveals the existence of at least nine different E $r^{3+}$ sites in this Er-implanted semiconductor. Most pf these E $r^{3+}$ PL centers are attributed to complexed of Er atoms with defects and impurities which are thermally activated at different $T_{A}$. Only one of the nine observed E $r^{3+}$ PL centers can be pumped by direct 4f absorption and this indicates that it is highest concentration E $r^{3+}$ center and it represents most of the optically active E $r^{3+}$ in the implanted sample. The fact that this E $r^{3+}$ center cannot be strongly pumped by above-gap light or broad band below-gap absorption indicates that it is an isolated center, i.e not complexed with defects or impurities, The 4f-pumped P: spectrum appears at annealing temperatures as low as 40$0^{\circ}C$, and although its intensity increase monotonically with increasing $T_{A}$ the wavelengths and linewidths of its characteristic peaks asre unaltered. The observation of this high quality E $r_{3+}$PL spectrum at low annealing temperatures illustrates that the crystalline structure of GaN is not rendered amorphous by the ion implantation. The increase of the PL intensities of the various E $R_{3+}$sites with increasing $T_{A}$is due to the removal of competing nonradiative channels with annealing. with annealing.annealing.

• 설비공학논문집
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• 제24권3호
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• pp.218-223
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• 2012

This study is focused on the evaluation of thermal output of TABS (Thermally Activated Building System). The aim of this study is to evaluate TABS in terms of the temperature difference between heating medium supply temperature ($T_s$) and return temperature ($T_r$), thermal output and the surface temperature distribution according to the design flow rate and the design flow temperature. Through the transient heat transfer simulation using temperature calculation using Crank-Nicolson FDM using Physibel Voltra 6.0 W, the temperature difference between $T_s$ and ��$T_r$, thermal output and the surface temperature distribution of specific TABS was calculated and evaluated. The results show that specific thermal output and temperature difference at $60^{\circ}C$ of supply water temperature were about 162 $W/m^2$, $13.6^{\circ}C$ respectively.

• Kyungpook Mathematical Journal
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• 제56권2호
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• pp.583-595
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• 2016

Archimedes showed that for a point P on a parabola X and a chord AB of X parallel to the tangent of X at P, the area S of the region bounded by the parabola X and chord AB is four thirds of the area T of triangle ${\Delta}ABP$. It is well known that the area U formed by three tangents to a parabola is half of the area T of the triangle formed by joining their points of contact. Recently, the first and third authors of the present paper and others proved that among strictly locally convex curves in the plane ${\mathbb{R}}^2$, these two properties are characteristic ones of parabolas. In this article, in order to generalize the above mentioned property $S={\frac{4}{3}}T$ for parabolas we study strictly locally convex curves in the plane ${\mathbb{R}}^2$ satisfying $S={\lambda}T+{\nu}U$, where ${\lambda}$ and ${\nu}$ are some functions on the curves. As a result, we present two conditions which are necessary and sufficient for a strictly locally convex curve in the plane to be an open arc of a parabola.

• Child Health Nursing Research
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• 제12권2호
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• pp.223-232
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• 2006

Purpose: The purpose of this study were to describe of resilience in children with chronic illness and family resilience, and to identify their correlations. Method: Data was collected from 108 children and their families, being treated by hospitals C and K in Seoul, who are diagnosed with nephrotic syndrome, IgA nephritis, diabetes, asthma at least six months ago. Descriptive, t-test, One-way ANOVA, and Pearson's Correlation were done. Result: The mean score of resilience in children was 101.31 and family resilience was 60.14. The variable which showed a statistically meaningful difference in the resilience in children according to a general characteristic was the gender of a child (t=6.209, p<.05), diagnosis (F= 6.315, p<.01), age of a mother (t=2.237, p<.05), and school grade (F=12.838, P<.01). In terms of the family resilience according to a general characteristic, the variable showing a statistically meaningful difference was the order of sibling (F=13.468, p<.01). There was significant positive resilience in children between family resilience (r=.356, p<.01). Conclusions: In this study we proposed the implement programs for the increase of the resilience in children with chronic illness. In order to give a positive effect on the resilience in children, implement for the increase of the family resilience is also proposed.

• 여성건강간호학회지
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• 제8권4호
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• pp.521-528
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• 2002

The purpose of this study was to identify the relationship between self reported climacteric symptoms, knowledge of menopause, menopausal management, in middle-aged women. The subjects of this study were 209 women from 40 to 64 years of age. The data was analyzed using SPSS program for t-test, ANOVA and Pearson's correlation coefficients. The results of the study were as follows : 1. The characteristic variables significantly related to self reported climacteric symptoms were education(F=6.371, p<0.001), income (F=4.481, p<0.05), mensturation state(t=-2.004, p<0.05), mensturation cycle(t=-2.039, p<0.05), hormone therapy(t=2.107, p<0.05), health condition(F=21.111, p<0.001). 2. The characteristic variables significantly related to knowledge of menopause were education(F=6.580, p<0.001), health condition (F=3.487, p<0.05). 3. The characteristic variable significantly related to menopausal management was income(F=3.080, p<0.05). 4. The relationship between self reported climacteric symptoms and menopausal management was statistically significant with a negative correlation(r=-0.323, p<0.05). In conclusion, climacteric symptoms - based complaints by middle-aged women was negatively correlated to menopausal management. Therefore, health promotions designed to increase climacteric women's health should be a planned program based on results of the study.