• Journal of the Korean Ceramic Society
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• v.38 no.11
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• pp.1046-1054
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• 2001

Effects of B$_2$O$_3$and CuO addition on the microwave dielectric properties of the PbWO$_4$-TiO$_2$ceramics were investigated in order to use this material as an LTCC material for fabrication of a multilayered RF passive components module. We found that PbWO$_4$could be used as an LTCC material because of its low sintering temperature (8$50^{\circ}C$) and fairy good microwave dielectric properties($\varepsilon$$_{r}$=21.5, Q$\times$f$_{0}$=37200 GHz and $\tau$$_{f}$ =-31 ppm/$^{\circ}C$). In order to stabilize $\tau$$_{f}$ of PbWO$_4$, TiO$_2$was added to the PbWO$_4$and the mixture was sintered at 8$50^{\circ}C$. A near zero $\tau$$_{f}$ value (+0.2 ppm/$^{\circ}C$) was obtained with 8.7 mol% TiO$_2$addition. $\varepsilon$r and Q$\times$f$_{0}$ values were 22.3 and 21400 GHz, respectively. It was believed that the decrement of Q$\times$f$_{0}$ value with TiO$_2$addition was resulted from increasing grain boundary. In order to improve Q$\times$f$_{0}$, various amounts of B$_2$O$_3$and CuO were added to the 0.913PbWO$_4$-0.087TiO$_2$mixture. The optimum amount of CuO was 0.05 wt%. At this addition, the 0.913PbWO$_4$-0.087TiO$_2$ceramic showed $\varepsilon$$_{r}$=23.5, $\tau$$_{f}$ =-2.2ppm/$^{\circ}C$, and Q$\times$f$_{0}$=32900 GHz after sintered at 8$50^{\circ}C$. In case of B$_2$O$_3$addition, the optimum amount range was 1.0~2.5 wt% at which we could obtain following results; $\varepsilon$$_{r}$=20.3~22.1, Q$\times$f$_{0}$=48700~54700 GHz, and $\tau$$_{f}$ =+2.4~+8.2ppm/$^{\circ}C$.

• Korean Journal of Materials Research
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• v.7 no.11
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• pp.934-941
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• 1997

C $r_{3}$ $C_{2}$-20wt% NiCr 이 크래드된 분말을 이용하여 HVOF 용사층의 특성(미세조직, 결정상, 경도 그리고 erosion rate)에 미치는 연료/산소 비(=3.2,3.0,2.8,2.6)의 영향을 조사했다. 실험범위 내에서 F/O=3.0의 경우가 C $r_{3}$ $C_{2}$-20wt%(NiCr)크래드 분말의 최적용사조건 이었다. XRD분석결과 F/O비에 관계없이 카바이드분해는 일어 났다. C $r_{3}$ $C_{2}$에서C $r_{7}$ $C_{3}$로의 상변화는 F/O비가 감소함에 따라 증가했다. 열처리 온도가 높아짐에 따라 C $r_{7}$ $C_{3}$분율은 증가 하였으며, 100$0^{\circ}C$에서 50시간 열처리후 용사층의 주된상은 C $r_{7}$ $C_{3}$이였다. 용사상태에서 경도값은 F/O=3.0조건으로 용사된 코팅층이 $H_{v300}$-1040으로 가장 높았으며, 공기중에서 $600^{\circ}C$, 50시간 열처리한 후, 경도값은 1340으로 증가하였다. 그리고 80$0^{\circ}C$열처리 후 경도값은 약간 감소하였다. 그러나 100$0^{\circ}C$ 열처리 후에도 1060정도로 용사상태의 경우 보다는 높은 경도값을 유지하였다. 이와같이 경도값이 증가하는 이유는 열처리에 따라 용사층이 치밀하게 되고 또한 C $r_{2}$ $O_{3}$의 산화물이 C $r_{3}$ $C_{2}$/C $r_{7}$ $C_{3}$ 내에 생성되어 탄화물/산화물 복합체를 이루기 때문으로 생각된다. 용사상태에서 drosion rate는 F/O비에 따라 2.6-3.05x$10^{-4}$mg/g까지 변화하였다. 또한 $600^{\circ}C$열처리 후에는 2.15-2.3 x $10^{-4}$mg/g이였으며, 80$0^{\circ}C$에서 열처리한 후에는 2.3-2.4x$10^{-4}$mg/g으로 $600^{\circ}C$열처리후 보다 약간 높은 결과를 보였다.결과를 보였다.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.2
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• pp.67-72
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• 2004

The microwave dielectric properties and microstructure of the (1-x)$Mg_4Ta_2O_{9-x}TiO_2$(X=0, 0.3, 0.4) ceramic were, investigated. The specimens were prepared by the conventional mixed oxide method with sintering temperature of $1350^{\circ}C$∼$1425^{\circ}C$. According to the XRD patterns, the (1-x)$Mg_4Ta_2O_{9-x}TiO_2$(X=0, 0.3, 0.4) ceramics have the $Mg_4Ta_2O_{9}$ phase(hexagonal). The dielectric constant($\varepsilon$$_{\gamma}$) and density increased with sintering temperature and mole fraction of x. To improve the quality factor and the temperature coefficient of resonant frequency, TiO$_2$($\varepsilon_{r}$=100, $Q{\times}f_{r}$=40,000GHz, $\tau$$_{f}$=＋450 ppm/$^{\circ}C$) was added in $Mg_4Ta_2O_{9}$ ceramics. In the case of the $0.7Mg_4Ta_2O_{9}$-$0.3TiO_2$ and the $0.6Mg_4Ta_2O_{9}$-$0.4TiO_2$ceramics sintered at $1400^{\circ}C$ for 5hr., the microwave dielectric properties were $\varepsilon$$_{\gamma}$=11.72, $Q{\times}f_{r}$=126,419GHz, $\tau_{f}$=-31.82 ppm/$^{\circ}C$ and $\varepsilon_{r}$=12.19, $Q{\times}f_{r}$=109,411GHZ, $\tau$$_{f}$= -17.21 ppm/$^{\circ}C$, respectively.

• The Korean Journal of Nuclear Medicine
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• v.19 no.1
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• pp.103-111
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• 1985

Recently changes in thyroid physiology during acute and chronic medical illness were demonstrated. The serum $fT_3,\;rT_3,\;T_4,\;T_3,\;fT_4$, and TSH concentration were measured by radioimmunoassay method in 49 patients with critical illness and 10 normal subjects to assess the change of thyroid function in critical illness. The results were as follows; 1) The mean serum $fT_3$ concentration was $6.68{\pm}1.05pmol/ml$ in normal subjects while in patients with critical illness the serum $fT_3$ concentration was significantly lowered to $1.55{\pm}1.15pmol/ml$(p<0.001). 2) The mean serum $rT_3$ concentration was $0.22{\pm}0.44ng/ml$ in normal subjects and $0.42{\pm}0.37ng/ml$ in patient with critical illness. There was increment in critically ill patients as compared to normal subjects but no statistically significant difference(p>0.05). 3) The mean serum $T_3$ concentration was $1.24{\pm}0.25ng/ml$ in normal subjects and $0.56{\pm}0.56ng/ml$ in patients with criticial illness and there was significant difference in each other(p<0.005). 4) The mean serum $T_4,\;fT_4$, and TSH concentrations were $7.80{\pm}1.02{\mu}g/dl,\;1.26{\pm}0.39ng/dl,\;1.87{\pm}0.45{\mu}U/ml$ in normal subjects respectively and $6.02{\pm}3.06{\mu}g/dl,\;1.46{\pm}0.80ng/dl,\;1.74{\pm}0.79{\mu}U/ml$ in patients with critical illness and there was no significant difference between critically ill patients and normal subjects. 5) The ratio of mean serum concentration of $fT_3$ and $rT_3(fT_3/rT_3)$, $30.42{\pm}5.58$ in normal subjects was significantly higher(p<0.005) than the coresponding patients with critical illness. 6) The mean serum $fT_3$ concentration in expired cases(n=12) during admission was significant difference between expired and survived cases(p<0.005). The mean serum $rT_3$ centration was $0.67{\pm}0.58ng/ml$ in expired cases and $0.34{\pm}0.22ng/ml$ in survived cases with significant difference(p<0.005). Half of the cases who showed less than $3{\mu}g/dl$ of serum $T_4$ level were expired.

• Journal of Nutrition and Health
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• v.3 no.2
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• pp.95-99
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• 1970

Korea is one of the typical rice eating countries where availability of animal protein is limited even for the growing generation. Nutritive food products for infants and children are not available commercially in large scale at the present time, although a limited amount of expensive milk products are produced. The present study deals with a pioneering attempt on a new food mixture to meet this demand. Several food mixtures, possibly produced in the country, consisting of rice, soybean, FPC, vitamin, minerals and other food additives are developed in this work Sixty female and male rats aged $30{\sim}40$ days were divided into five groups, twelve rats each. The rats had been maintained with the six different diets, as follow. Formulation of proposed infant food mixturesComposition F-R-1 F-S-2 F-F-3 F-P-4 S Rice 100% 40% 37% 46% 70% Sugar - 12 13 10 70 Casein - - - - 20 Bean - 40 37 24 - Yeast - 3 2 3 - Mineral Vitamain - 2 4 2 4.3 F.P.C - 3 4 7 - Fat - - 4 8 4 Cod liver Oil - - - - 3 The findings of this study presented in FER, PER, final organ weights, body weights growth, percentage of nitrogen retention in the body. F-P-4 group tended to remain the heaviest and F-R-1 the lightest in the body weight among three groups throughout the experimental period. In terms of FER (Feed Efficiency Ratio) and PER (Prortein E. R.) value, F-P-4 group kept the highest record throughout. F-P-4 group showed the highest value of nitrogen retention in the body. In comparision between F-P-4 groups and casein 20% group (standard) in all respects of this experiment, F-P-4 group which is the most superior among experimental group, revealed statisfically no significant inferior than that of standard group. This fact could be interpreted that most limiting a. a., methionine in the soy protein produced little inferiority of the experimental groups in the study.

• Journal of the Korean Wood Science and Technology
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• v.8 no.1
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• pp.22-27
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• 1980

Quantitative assessment of edge blunting of saw-teeth was carried out by TALYSURF. 1. Using the following equation, the real shape of a saw-tooth can be traced on the graph of TALYSURF. ${\frac{{\Delta}h}{h}}={\frac{V{\Delta}_x}{V_x}}$ {${\Delta}h$: vertical distance of stylus h: vertical distance in chart $V{\Delta}_x$: Velocity of stylus $V_x$: velocity of chart} 2. As shown on Fig 2, the error from stylus itself can be calculated by following equation. i) 13.8${\mu}{\leqq}$x<20.4${\mu}$ y=-0.2246x+4.59${\mu}$ ii) 0${\leqq}$x<13.8${\mu}$ y=${\sqrt{(-18{\mu})^2-x^2}}-1.42x+32.7{\mu}}$ 3. The relationship between profile of saw-tooth and error from stylus itself can be calculated by following equation. $E(%)=\frac{f(r){\times}{\frac{4}{18{\mu}}}}{f(R){\times}{\frac{R}{18.5{\mu}}}-f(r){\times}{\frac{r}{18{\mu}}}}{\times}100$ {E(%)${\frac{error\;of\;stylus}{dullness\;of\;saw\;tooth}}{\times}100$ r: radius of stylus tip R: radius of tip which is drawn in graph of talysurf f(r) : error of stylus f(R) : dullness of tip which is drawn in graph of talysurf} 4. The graph of maximum error and profile of saw-tooth was parabola.

• Journal of Korean Academy of Nursing
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• v.30 no.3
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• pp.571-583
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• 2000

The purpose of this study was to identify the level of self-disclosure and clinical competency and the relationships between self-disclosure and clinical competency in nursing students. The subjects were consisted of 662 nursing students from six universities and five junior colleges. The data were collected conveniently by self reporting questionnaires given to the students from September 13 to October 23, 1999. The instruments for this study were JSDQ and clinical competency measurement tool. The data were analyzed by SAS/PC program using descriptive statistics, t-test, ANOVA, Pearson correlation coefficient. The results of this study are as follows : 1. The mean score for the level of self- disclosure was 3.29$\pm$0.98. 2. The mean score for the level of clinical competency was 3.93$\pm$1.00. The mean score for the dimension of skills, professional attitudes, teaching and coordinating, nursing process, interpersonal relationships were 4.09$\pm$0.77, 4.08$\pm$0.82, 3.97$\pm$ 0.90, 3.77$\pm$0.76 and 3.37$\pm$0.75 respectively. 3. The statistically significant difference in the score of the self-disclosure according to the educational background (F=9.42, p<.01), grade (F=5.59, p<.01), religion (F=2.68, p<.05), satisfaction of nursing major (F=14.20, p<.0001), and satisfaction of nursing practice (F=5.42, p<.01) was obtained. 4. The statistically significant difference in the score of the clinical competency according to the grade (F=32.44, p<.0001), achieved performance records (F=3.52, p<.05), satisfaction of nursing major (F=12.06, p<.0001), satisfaction of nursing practice (F=27.35, p<.0001) was obtained. 5. The data shows the positive correlations between self-disclosure and skill (r=.3231, p<.0001), between self- disclosure and teaching/coordinating (r=.1912, p<.0001), between self-disclosure and interpersonal relationship (r=.3064, p<.0001), between self-disclosure and professional attitude (r=.2789, p<.0001), between self-disclosure and nursing process (r=.2766, p<.0001).

• Journal of Korean Public Health Nursing
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• v.13 no.2
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• pp.143-160
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• 1999

The purpose of this descriptive survey study was to examine the following items. 1) Score distribution of life satisfaction. powerlessness. perceived health status and self-esteem 2) Demographic characteristics and the affection of socioeconomic characterictics to life satisfaction. powerlessness. perceived health status and self-esteem 3) Correlationship between life satisfaction. powerlessness. perceived health status and self-esteem 4) Determining the factors affecting life satisfaction The subjects were 167 urban elderly people. Data were collected from May to July in 1998 using the questionaires. The data were analyzed by mean. ANOVA. Pearson correlation coefficient and stepwise multiple regression with SPSS win 7.5 program. The results were as follows : 1) The degree of life satisfaction and powerlessness were relatively low with the mean score of 42.4 and 39.79 respectively. and perceived health status and self-esteem were relatively high with the mean score of 3.15 out of 5 and 27.3 respectively. 2) There were no significant differences between demographic characteristics and life satisfaction. Education(F=2.91. p=0.02), previous employment(F=2.23. p=0.03) and marital status(F=3.85. p=0.04) showed significant differences in the relationship between demographic characteristics and powerlessness. Sex(F=6.40. p=0.0l). education(F=3.30. p=0.0l). marital status(F=7.13. p=0.008) and kinds of living togather(F=3.69. p=0.003) showed significant differences in the relationship between demographic characteristics and perceived health status. There were no significant differences between demographic characeristics and self-esteem. 3) Monthly allowance(F=3.68. p=0.007). participation in social activity(F=5.90. p=0.000) and number of social activities(F=5.27. p=0.000) showed significant differences in the relationship between socioeconomic characteristics and life satisfaction. Monthly allowance(F=3.13. p=0.01) and number of social activities(F=2.7. p=0.02) showed significant differences in the relationship between socioeconomic characteristics and powerlessness. There were no significant differences between socioeconomic characteristics and perceived health status. Montly allowance(F=4.82. p=0.001). particpation in social activity(F=2.90. p=0.02) and number of social activities(F=3.79. p=0.003) showed significant differences m the relationship between socioeconomic characteristics and self-esteem. 4) Powerlessness showed negative correltionship with perceived health staus(r=-0.295. p<0.001). self-esteem(r=-0.463. p<0.001) and life satisfaction(r=-0.514. p<0.001). Perceived health status showed positive correltionship with self-esteem(r=0.312. p<0.001) and life satisfaction (r=0.377. p<0.001). Self-esteem showed positive correlationship with life satisfaction(r=0.652. p(<0.001). 5) The predicting variances for life satisfaction m elderly people were self-esteem. powerlessness. participation in social activity and perceived health status. The most influencing factor among the variances was the self-esteem$(42.5\%)$ and powerlessness was the second. Both of self-esteem and powerlessness accounted for $48.2\%$ in life satisfaction. The addition of participation of social activity and perceived health status accounted for $52.9\%$ in life satisfaction.

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.2012-2016
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• 2012

A convenient synthetic route has been developed to synthesize 5-(4-((2-phenylthiazol-4-yl) methoxy)phenyl)-3-(4-sustituted phenyl)pyrazolines (5a-f) and 5-(4-((2-phenylthiazol-4-yl)methoxy)phenyl)-3-(4-substituted phenyl)isoxazolines (6a-f) starting from 2-phenyl-4-chloromethylthiazole (1). The chloromethylthiazole (1) was first condensed with 4-hydroxy benzaldehyde (2) for obtaining 4-((2-phenylthiazol-4-yl)methoxy)benzaldehyde (3). Claisen-Smidth condensation of 4-((2-phenylthiazol-4-yl)methoxy)benzaldehyde (3) and acetophenones has been carried in alkaline alcohol and obtained 3-(4-((2-phenylthiazol-4-yl)methoxy)phenyl)-1-(4-substituted phenyl)prop-2-en-1-ones (4a-f). The cyclocondensation of 2-propen-1-ones has been first time carried separately with hydrazine hydrate and hydroxylamine hydrochloride in aqueous micellar tetradecyltrimethylammonium bromide (TTAB) medium for getting the titled heterocycles with good to excellent yields.

• Honam Mathematical Journal
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• v.8 no.1
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• pp.51-74
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• 1986

The thery of measure is significant in that we extend from it to the theory of integration. AS specific metric outer measures we can take Hausdorff outer measure and Lebesgue-Stieltjes outer measure connecting measure with monotone functions.([12]) The purpose of this paper is to find some properties of Lebesgue-Stieltjes measure by extending it from $R^1$ to $R^n(n{\geq}1)$ $({\S}3)$ and differentiation of the integral defined by Borel measure $({\S}4)$. If in detail, as follows. We proved that if $_n{\lambda}_{f}^{\ast}$ is Lebesgue-Stieltjes outer measure defined on a finite monotone increasing function $f:R{\rightarrow}R$ with the right continuity, then $$_n{\lambda}_{f}^{\ast}(I)=\prod_{j=1}^{n}(f(b_j)-f(a_j))$$, where $I={(x_1,...,x_n){\mid}a_j$<$x_j{\leq}b_j,\;j=1,...,n}$. (Theorem 3.6). We've reached the conclusion of an extension of Lebesgue Differentiation Theorem in the course of proving that the class of continuous function on $R^n$ with compact support is dense in $L^p(d{\mu})$ ($1{\leq$}p<$\infty$) (Proposition 2.4). That is, if f is locally $\mu$-integrable on $R^n$, then $\lim_{h\to\0}\left(\frac{1}{{\mu}(Q_x(h))}\right)\int_{Qx(h)}f\;d{\mu}=f(x)\;a.e.(\mu)$.