• Title/Summary/Keyword: content factor

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Electrodeposition of Antimony Telluride Thin Films and Composition-Dependent Thermoelectric Characterization

  • Kim, Jiwon
    • Journal of the Korean Electrochemical Society
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    • v.23 no.1
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    • pp.18-23
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    • 2020
  • Antimony telluride (SbxTey) thin films were synthesized by an electrodeposition method with a control of applied potential at room temperature. Characterization of electrical and thermoelectric properties such as conductivity, Seebeck coefficient, and power factor (P.F.) were conducted as a function of the chemical composition of the electrodeposited films. Morphology of thin films were dense and uniform and the composition was tailored from 25 to 60 at.% of the Sb content by altering the applied potential from -0.13 to -0.27 V (vs. SCE). The conductivity of the films were ranged from 2 × 10-4 ~ 5 × 10-1 S/cm indicating their amorphous behavior. The meaured Seebeck coefficient of films were relatively high compared to that of bulk single cyrstal SbxTey due to their low carrier concentration. The variation of the Seebeck coefficient of the films was also related to the change of chemical composition, showing the power factor of ~10 ㎼/mK2.

Characterization of Ferrous Metal Artifacts by Microstructure Observation (미세구조 관찰에 의한 철제금속유물의 특성화)

  • Huh, Wooyoung;Lee, Chul
    • Analytical Science and Technology
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    • v.11 no.4
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    • pp.316-320
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    • 1998
  • An image analysis was used for the interpretation of microstructures of ferrous metal artifacts. For the purposes, various microstructural features such as average grain size, phase area, shape factor, and composition of the inclusions, were parameterized for the information about manufacturing techniques such as casting, heating and tempering. The carbon content was determined through the evaluation of the amount of pearlite phase. As the amount of pearlite phase increased the shape factor also increased. Grain size was relatively smaller in trans-section than in cross-section. The manufacturing direction was trans-sectional because the orientation of inclusions was elongated lengthwise. All inclusions was of silicate groups and the manufacturing temperature was estimated up to $1450^{\circ}C$.

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Specific and Sensitive Detection of the Pear Scab Fungus Venturia nashicola by SYBR Green Real-Time PCR

  • Yun, Yeo Hong;Yoon, Seong Kwon;Jung, Jae Sung;Kim, Seong Hwan
    • Journal of Microbiology and Biotechnology
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    • v.25 no.11
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    • pp.1782-1786
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    • 2015
  • A new improved PCR method has been developed for the rapid, reliable, and sensitive detection of Venturia nashicola, a destructive pathogen of scab disease in Japanese pear. The translation elongation factor-1 alpha gene-derived PCR primers specifically amplified a 257-bp-sized DNA band of the target gene from the genomic DNA of V. nashicola. No amplicon was produced from the genomic DNA of other Venturia spp. and reference fungal species tested. With the high detection limit of 10 fg DNA content, our real-time method could be used for the quarantine inspection and field monitoring of V. nashicola.

A Study on Boost Converter for Power Factor Correction (역률 개선을 위한 승압형 컨버터에 대한 연구)

  • Lee, C.H.;Kim, D.U.;Lee, S.G.;Sung, N.K.;Lee, S.H.;Oh, B.H.;Han, K.H.
    • Proceedings of the KIEE Conference
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    • 2001.07b
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    • pp.1052-1054
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    • 2001
  • This paper describes a boost converter to be operated at the boundary of continuous current mode(CCM) and discontinuous current mode(DCM) for power factor correction and low cost. A control method to be utilized in simulation is a average-current mode method in case of operating in CCM. The simulation results show that Better is the CCM converter then the DCM converter in harmonic content and input current waveform. And A Double-boost converter is superior to single-boost converter for input-current harmonic.

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Statistical Analysis of Main Factors With Affecting the Physical Properties of Rubber Compounds (고무조성물의 물리적 성질에 영향을 미치는 주요인자에 대한 통계학적 해석)

  • Lee, Seag;Park, Nam-Cook
    • Elastomers and Composites
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    • v.32 no.1
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    • pp.20-28
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    • 1997
  • This study have Investigated the effect of various factors related to the physical properties of vulcanizated rubber compounds. rubber type, carbon black type and carbon black loading were selected as main factors and evaluation were tested by tables of orthogonal arrays with 3 factors and 3 levels. rubber types have affected cure time, tensile strength, and $T_g$ as main factor and carbon black loading have affected viscosity, scorch time, maximum torque, hardness, 300% modulus, rebound, heat build-up, $0\;&\;60^{\circ}C$ tangent delta, PICO and CUT/CHIP loss as main factor but the effects of carbon black type have affected only bound rubber content.

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Development and Validation of Korean Sleep Scale A (수면측정 도구의 개발을 위한 연구)

  • 오진주;송미순;김신미
    • Journal of Korean Academy of Nursing
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    • v.28 no.3
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    • pp.563-572
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    • 1998
  • The purpose of study was to develop and validate Korean Sleep Scale A which can be easily administrated by nurses for a wide range of adult subjects. Dimensions of sleep concept were derived by literature review. Previously developed sleep sclaes were also analyzed in order to develop scale items. The Korean sleep scale A was structured as a 15 item, 4 point likert type scale. The Scale was tested an 298 female and male adult subjects after pilottest and content validation. The results showed reliability by internal consistency of Cronbach's α=.75 Construct validity was tested by factor analysis and known group technique. Factor analysis showed 4 factors-sleep pattern, sleep evaluation, sleep result, and cause of sleep disturbance. These four factors explained 55.9% of total variance. Correlations between factors ranged from .15-.32. There was correlation among Korean Sleep ScaleA score, Verran and Snyder-Halpern(VSH) Sleep Scale score, and sleep satisfaction scale score, r=.71(p=.00), r=.51(p=.03), respectively, These study results partially support reliability, construct validity, and criterion related validity of Korean Sleep Scale A. Further validation study is required with other subjects and other settings.

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Blood Chemistry in Periodontal Disease (치주질환시의 혈생화학적연구)

  • Han, K.H.
    • The Journal of Korean Academy of Prosthodontics
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    • v.9 no.1
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    • pp.59-62
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    • 1969
  • The causes of periodontal disease have been descried as malocclusion, trauma from occlusion, local irritants and poor oral hygien. The systemic factor has also been considered as a etiologic factor of periodontal disease. On the other aspect systemic condition could be affected by periodontal disease. For the study of relationships between periodontal disease and systemic condition, twenty patients with periodontal disease and twenty persons with no periodontal involvement were evaluated for inorganic elements and organic materials in the blood. The results of the blood analysis of the two groups were as follows. : Phosphorus and alkline-phoshatase in the group with periodontal disease showed slightly increased phenomenon compared to the control group, and on the other hand calcium and calcium-phosphorus ratio decreased phenomenon. But there is no any significant alteration in the content of each element between the two groups.

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Establishment of Proper Toasting Condition on Burley Leaf Tobacco (버어리 잎담배의 적정 토스트 가동 조건 설정)

  • 정한주;김용옥
    • Journal of the Korean Society of Tobacco Science
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    • v.26 no.1
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    • pp.50-56
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    • 2004
  • The quality of burley leaf tobacco was affected by various toasting conditions. In this study, we determined main factor to influence the quality of burley tobacco on toasting and established proper toasting condition to improve the quality of toasted tobacco. Our results indicated that the main factor to influence the quality of burley tobacco was the amount of treatment and 3rd drying zone temperature. We also found that the proper toasting conditions to improve the quality of toasted tobacco and reduce the smoking irritation were moisture content (34 %), amount of treatment (1,520kg/hr), 1st drying zone temperature (135$^{\circ}C$), 2nd zone drying temperature(145$^{\circ}C$) and 3rd zone drying temperature (147$^{\circ}C$).

Estimation of Soil Volume Conversion Factors using Nondestructive Testing Methods (비파괴시험기법을 이용한 토량환산계수 산정 방법 제시)

  • Son, Thai An;Ryu, Hee-Hwan;Cho, Gye-Chun;Hong, Eun-Soo;Jin, Gyu-Nam
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.03a
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    • pp.717-721
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    • 2010
  • Soil volume conversion factors are used for estimation of an excavated the soil volume which will be removed or added in levelling the ground surface of a construction site. An accurate evaluation method will help us reduce a construction cost and time consuming. In this study, we performed the laboratory tests, including grain size measurement, water content, specific gravity, porosity, density and XRD tests, to suggest reliable soil volume conversion factors and weathering indices in field using nondestructive methods. The weathering index and soil volume conversion factor L are obtained for different types of soils. At results, the CIW index is the best method measuring the weathering index and the factor L is relative to natural porosity, void ratio, density and dry density.

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Influence of the Mixing Factor on the Properties of Concrete Used Artificial Lightweight Aggregates (인공경량골재를 사용한 콘크리트의 물성에 미치는 배합요인의 영향)

  • Shin, Jae-Kyung;Choi, Jin-Man;Jeong, Yong
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2008.11a
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    • pp.73-77
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    • 2008
  • Structural lightweight concrete will reduced total loads of supporting sections and foundations in archtectural and civil structures. So, the lightweight concrete can be used widely for various purpose in the archtectural and civil structures. This paper were examined the influence of the mixing factor on the fresh and hardened properties of lightweight concrete that are used 2types of the differences properties of lightweight aggregates. According to types of lightweight aggregates, the case of synthetic lightweight aggregate are have need higher s/a; 2~4% on mixing proportion. Lightweight concrete was somewhat exhibit lower compressive strength than ordinary concrete. However it was not showed a marked difference. According to types of lightweight aggregates, the case of synthetic the lightweight aggregate are highest performance in fresh and hardened concrete.

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