• 제목/요약/키워드: composition factor

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소결조제 첨가에 따른 PMW-PMN-PZT 세라믹의 저온소결 특성 (Low temperature sintering properties of the $Pb(Mg_{1/2}W_{1/2})O_3-Pb(Mn_{1/3}Nb_{2/3})O_3-Pb(Zi,Ti)O_3$ ceramics with the addition of sintering aids)

  • 이현석;류주현;이창배;정영호;백동수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.350-351
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    • 2005
  • In this study, in order to develop the low temperature sintering multilayer piezoelectric transformer, PMW-PMN-PZT system ceramics were manufactured with the addition of sintering aids, and their dielectric and piezoelectric characteristics were investigated. At the composition ceramics sintered at $900^{\circ}C$, dielectric constant(${\varepsilon}r$), electromechanical coupling factor(kp) and mechanical quality factor(Qm) showed the optimal value of 1043, 0.44 and 793, respectively, for multilayer piezoelectric transformer application.

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30대 여성 유방형태 분류에 관한 연구 (A Study on Classification of Breast Shapes for Women in Their 30s)

  • 김효숙;김지민
    • 복식
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    • 제64권4호
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    • pp.106-117
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    • 2014
  • The purpose of this study is to provide basic information for the development of well-fitting and comfortable brassieres for women in their 30s, based on the classification of breast shapes by utilizing 3D body measurement data of women in the age group. The result of processing the measurements from the 3D body scan data through RapidForm 2006 shows that while the vertical body measurements decrease, the horizontal measurements, which indicates the degree of obesity, increase proportionally with age. Also, the relevant measurements for upper breasts increase proportionally with age, while the measurements for lower part of the breasts decrease as the degree of sagging increases. Four composition factors of the breasts were identified through the factor analysis: Factor 1 is the level of volume in the breasts and the surrounding area; Factor 2 is the position of nipples and the shape of upper part of breasts; Factor 3 is the position and vertical length of the breasts; Factor 4 is the shape of lower part of breasts; and Factor 5 is the shape of inner part of breasts and degree of width between both breasts. The breasts have been categorized into three distinctive shapes: Breast Shape 1, Breast Shape 2 and Breast Shape 3. According to the results of the cluster analysis, the largest percentage (36.68%) of women in their 30s falls into the category of Breast Shape 2 with small volume and flat upper breasts, followed by Breast Shape 1 (32.66%) with large volume in the upper and lower parts of breasts, and large side to side area, and Breast Shape 3 (30.65%) with average volume and width between breasts.

이용계수를 적용한 공공도서관 소설장서 평가 (Evaluation of the Fiction Collection of Public Libraries Based on Use Factor)

  • 윤희윤;김일영
    • 정보관리연구
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    • 제42권4호
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    • pp.175-194
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    • 2011
  • 본 연구는 이용계수를 적용하여 국내 공공도서관의 소설장서를 평가하고 장서개발기능을 제고시키기 위한 다양한 방안을 제시하였다. 그 결과, 한국문학은 언어별 문학에서의 장서구성 및 이용대출 비중이 각각 62.6%와 54.3%로 가장 높았음에도 불구하고 이용계수(0.87)는 기준값(1.00)보다 낮았다. 또한 한국현대소설은 한국소설의 세목별 장서구성 및 이용대출에서의 비중이 각각 65.60%와 51.36%로 가장 높음에도 이용계수(0.78)는 기준값보다 낮았고 연도별 이용계수도 최근 연도에 근접할수록 감소하고 있다. 그 이유는 장서개발이 부실하기 때문이다. 그러므로 공공도서관은 장서개발정책 및 소설장서개발지침의 수립, 소설자료선정위원회의 구성, 소설자료개발 전담사서제 도입, 소설자료 선정도구의 개발과 활용, 소설장서의 주기적 평가와 같은 방안의 도입을 적극적으로 검토할 필요가 있다.

도펀트 첨가에 따른 0.57Pb(Sc1/2Nb1/2)O3-0.43PbTiO3 세라믹스의 유전 및 압전특성 (Dielectric and Piezoelectric Properties of 0.57Pb(Sc1/2Nb1/2)O3-0.43PbTiO3 Ceramics with Dopant Additions)

  • 지승한;권상직
    • 한국전기전자재료학회논문지
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    • 제20권2호
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    • pp.124-129
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    • 2007
  • Dielectric and piezoelectric properties of $0.57Pb(Sc_{1/2}Nb_{1/2})O_{3}-0.43PbTiO_{3}$, which is the morphotropic phase boundary composition for the PSN-PT system, were investigated as a function of $Fe_{2}O_{3},\;Nb_{2}O_{5}\;and\;MnO_{2}$ addition 0 wt% to 0.9 wt%. The maximum dielectric constant of ${\varepsilon}_{33}/{\varepsilon}_{o}=2054$ and the minimum dielectric loss of $tan{\delta}=0.37\;%$ at room temperature were obtained at 0.1 wt% of $Fe_{2}O_{3}$ and 0.5 wt% of $MnO_{2}$ addition, respectively. With addition of 0.5 wt% $Nb_{2}O_{5}$ and $0.5\;wt%\;MnO_{2}$, the electromechanical coupling factor $k_{p}$ and mecanical quality factor $Q_{m}$ were significantly increased, respectively. The maximum electromechanical coupling factor $k_{p}=61.5\;%$ was obtained by addition of $Nb_{2}O_{5}$ and high mechanical quality factor $Q_{m}=919$ was obtained by addition of $MnO_{2}$. The $Q_{m}(=919)$ value is 3.3 times larger than that of non-doped 0.57PSN-0.43PT ceramics.

Improving sugarcane bagasse quality as ruminant feed with Lactobacillus, cellulase, and molasses

  • So, Sarong;Cherdthong, Anusorn;Wanapat, Metha
    • Journal of Animal Science and Technology
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    • 제62권5호
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    • pp.648-658
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    • 2020
  • The objective of the study was to evaluate the effects of Lactobacillus, cellulase, and molasses on chemical composition, fermentation qualities, and microorganism count of sugarcane bagasse silage after 30-days fermentation. The treatments were arranged according to a factorial arrangement (2 × 2 × 2) + 1, in a complete randomized design. The first factor consisted of two levels of Lactobacillus casei TH14 (TH14, 0 and 0.05 g/kg fresh matter; the second factor consisted of two levels of cellulase enzyme (C, 0 and 104 U/kg fresh matter); and the third factor consisted of two levels of molasses (M, 0 and 5 g/ 100 mL distilled water). A treatment (+1) referred to the use of rice straw without any treatments. The result showed that dry matter increased by 4% and neutral detergent fiber decreased by 2% of sugarcane bagasse when ensiled as a combination of additives as compared to untreated sugarcane bagasse. The pH and ammonia nitrogen were significantly dropped to 3.5 and 2.3 g/kg dry matter. Furthermore, lactic acid was increased by 64% when compared to untreated sugarcane bagasse, respectively. Lactic acid bacteria count was increased by 28% as compared to untreated sugarcane bagasse. Based on this experiment, fermenting with L. casei TH14, cellulase, and molasses in combination resulted in the promotion of the best qualities of sugarcane bagasse silage.

CuO첨가에 따른 $(K_{0.5}Na_{0.5})_{0.97}(Nb_{0.96}Sb_{0.04})O_3$세라믹스의 유전 및 압전 특성 (Dielectric and piezoelectric properties of CuO added $(K_{0.5}Na_{0.5})_{0.97}(Nb_{0.96}Sb_{0.04})O_3$ ceramics)

  • 이유형;박민호;노정래;류주현;김인성;송재성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 하계학술대회 논문집
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    • pp.160-161
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    • 2009
  • In this study, in order to develop the lead free piezoelectric ceramics with excellent piezoelectric properties, (Na,K)$NbO_3$ ceramics according to the amount CuO addition were fabricated using a conventional mixed oxide process and their piezoelectric and dielectric characteristics were investigated. At the 0.8mol% CuO added composition, density, electromechanical coupling factor(kp), echanical quality factor(Qm), dielectric constant$(\varepsilon_r$) and piezoelectric constant($d_{33}$) showed the optimum value of $4.459g/cm^3$, 0.469, 540, 410, 69.57pC/N, respectively.

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보수율을 고려한 조명시스템의 경제성 평가 (The Economics Evaluation of Lighting System Considering Maintenance Factor)

  • 심상만;김기훈;황남극;김훈
    • 조명전기설비학회논문지
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    • 제15권5호
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    • pp.1-7
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    • 2001
  • 조명시스템의 경제성에 크게 영향을 주는 요소들을 보면 초기 설비비, 보수비, 전기요금 등이 있다. 이 중에서 보수비는 램프 교환비, 램프교환 인건비, 청소비로 구성되어 있으므로 부소계획에 따라서 조명시스템의 경제성이 다르게 나타난다. 따라서 설계초기에 어떠한 조명시스템이 경제적으로 유리한가를 예측하는 것은 중요하다. 그러므로 본 연구에서는 평균조도를 계산하는데 사용되는 ZCM에서의 보수율 구성 요소들을 변화시켜 보수율을 산정한 다음 조명시스템의 경제성을 평가하여 보수율의 중요성을 보였다.

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한국어판 다낭성 난소 증후군 삶의 질 측정도구의 타당도와 신뢰도 (Validity and Reliability of a Korean version of Polycystic Ovary Syndrome Questionnaire)

  • 오주혜;김주희
    • 여성건강간호학회지
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    • 제20권4호
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    • pp.255-265
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    • 2014
  • Purpose: Polycystic Ovary Syndrome Questionnaire (PCOSQ) was developed to measure health-related quality of life of women who had polycystic ovary syndrome. The purpose of this study was to exam reliability and validity of the Korean version of PCOSQ. Methods: A sample of 101 women who had polycystic ovarian syndrome was recruited from outpatient gynecology clinics. Factor analysis was carried out to verify the composition of dimensions of the Korean version of PCOSQ. Concurrent validity was examined by assessing the correlation between the PCOSQ and health related quality of life, and convergent validity was evaluated by testing correlation between PCOSQ and depression. Reliability was assessed using Cronbach's ${\alpha}$. Results: The content validitywas satisfactory (CVI=0.85). Factor analysis identified 5 factors, and factor loadings of the PCOSQ ranged from .48 to .90. Correlation was found between the PCOSQ and health related quality of life (Physical component score: r=.33, p=.001; Mental component score: r=.44, p<.001) and between the PCOSQand depression (r=-.36, p<.001). The Cronbach's ${\alpha}$ of the PCOSQ was .93, indicating reliable reliability. Conclusion: These results demonstrate that the Korean version of PCOSQ is a reliable and valid instrument for evaluating Korean-speaking women with polycystic ovarian syndrome.

적층 압전변압기용 저온소결 PMN-PZT 압전세라믹의 소성시간에 따른 미세구조 및 압전특성 (Microstructural and piezoelectric properties of low temperature sintering PMN-PZT ceramics for multilayer piezoelectric transformer with the variations of sintering times)

  • 이창배;류주현;이상호;백동수;정영호;윤현상;임인호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.425-430
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    • 2004
  • In this paper, in order to develop the low temperature sintering ceramics for multilayer piezoelectric transformer, PMN-PZT ceramics were manufactured with the variations of sintering times, and their microstructural, piezoelectric and dielectric properties were investigated. To manufacture multilayer piezoelectric transformer, the low temperature sintering composition is need, hence, $Li_2CO_3$ and $Bi_2O_3$ were used as sintering aids and the specimens were sintered during 30, 60, 90, 120, 150 and 180 minutes, respectively. At the specimen sintered during 90 minute, mechanical quality factor(Qm), electromechanical coupling factor(kp) and dielectric constant were showed the optimum values of 2356, 0.504 and 1266, respectively. All the specimens showed tetragonality phase, and pyrochlore phase was not shown.

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Theoretical Calculation and Experimental Verification of the Hf/Al Concentration Ratio in Nano-mixed $Hf_xAl_yO_z$ Films Prepared by Atomic Layer Deposition

  • Kil, Deok-Sin;Yeom, Seung-Jin;Hong, Kwon;Roh, Jae-Sung;Sohn, Hyun-Cheol;Kim, Jin-Woong;Park, Sung-Wook
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제5권2호
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    • pp.120-126
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    • 2005
  • We have proposed a characteristic method to estimate real composition when multi component oxide films are deposited by ALD. Final atomic concentration ratio was theoretically calculated from the film densities and growth rates for $HfO_2$ and $Al_2O_3$ using ALD processed HfxAhOz mms.W e have transformed initial source feeding ratio during deposition to fins] atomic ratio in $Hf_xAl_yO_z$ films through thickness factors ($R_{HFO_2}$ ami $R_{Al_2O_3}$) ami concentration factor(C) defined in our experiments. Initial source feeding ratio could be transformed into the thickness ratio by each thickness factor. Final atomic ratio was calculated from thickness ratio by concentration factor. It has been successfully confirmed that the predicted atomic ratio was in good agreement with the actual measured value by ICP-MS analysis.