• 제목/요약/키워드: Reduction against segregation

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유동화제와 증점제의 조성비가 자기수평 칼라 모르타르의 재료분리저감에 미치는 영향에 관한 실험적 연구 (A Study on the Segregation Reduction of Self-Leveling Color Mortar by Using Variable Composition Set of Plasticizer and Thickener)

  • 채우병;선윤숙;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
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    • pp.101-106
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    • 2009
  • We study on the segregation reduction effect of Self-Leveling Color Mortar by using variable composition set of plasticizer and thickener, Naphthalene, melamine and polycarbonate-based dispersants were employed as plasticizers for examining on fluidity of mortar mixtures. For enhancement of mortar stability without loss of it's fluidity, two types of thickener were used such as polysaccharide(PS) and hydroxyethylcellulose(HEC). As a result, the most effective mortar was composed by feeding 0.519% of polycarbonate-based dispersant with 0.002587% of PS and 0.155844% of HEC on amount of basic mortar.

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Analysis of Gender Pay Gap in Different Sectors of the Economy in Kazakhstan

  • KIREYEVA, Anel A.;SATYBALDIN, Azimkhan A.
    • The Journal of Asian Finance, Economics and Business
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    • 제6권2호
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    • pp.231-238
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    • 2019
  • This study aims is to analyze of existing concepts of gender stereotypes and gender differences in wages, defining of gender pay gap determinants, and to evaluate the level of discrimination against women in Kazakhstan. This paper begins by reviewing trends in gender stereotypes and gender segregation during the past several decades. In this research, authors propose the methodological tools for presenting a standard form of evaluation of gender pay gap. The developed methodological tools will allow providing authentic and formal analysis on gender pay gap and identifying the main determinants of gender pay differences. Further, the obtained results showed the distribution of wage gap in Kazakhstan's regions and the Duncan's dissimilation index allows us to trace the dynamics of changes in the professional structure between men and women. According to the results, gender pay gap is narrowing with the reduction of the job level and discrimination is related to differences in human capital and education. Wages in the industrial sector are higher for men than for women, because men's professions are characterized by severe and unhealthy working conditions. In addition, employers prefer male managers, but if they take woman managers, they give them salary 3 times less.

Structural Stability and the Electronic Structure of InP/GaP Superlattices

  • Park, Cheol-Hong;Chang, Kee-Joo
    • ETRI Journal
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    • 제13권4호
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    • pp.25-34
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    • 1991
  • The stability and the electronic structure of $In_0.5$.$Ga_0.5$P-based superlattices are examined through self-consistent ab initio pseudopotential calculations. A chalcopyrite-like structure is found to be the lowest energy state over (001) and (111) monolayer superlattices (MLS). Our calculations indicate that all the ordered structures in bulk form are unstable against phase segregation into binary constituents at T = 0 while for epitaxial growth, the chalcopyrite phase is stabilized. The fundamental band gaps of the ordered structures are found to be direct and smaller than that of disordered alloys. The lowering of the band gap is explainable by band folding and pushing effects. We find the reduction of the band gap to be largest for the (111) MLS.

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고유동콘크리트의 특성에 관한 실험적 연구 (A Study of the Characteristics of the High-Flowable Concrete)

  • 전현규;김대회;이종찬;지석원;유택동;서치호
    • 한국건축시공학회지
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    • 제3권2호
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    • pp.129-134
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    • 2003
  • In this research, we used fly-ash and blast-furnace slag as substitute material of cement and fine aggregate, and we, through experiments, researched and analyzed the features of high-flowable concrete added high efficiency AE water reduction agent. The results are below. 1. Liquefaction generally presented high-slump flow value; on the other hand, partial segregation was observed in case of mixing proportion with 65 cm slump flow and above. This segregation was partially improved in accordance with mixing admixture. 2. Compressive strength according to mixing admixture and increasing mixing ratio of fly-ash were subject to be declined when it was initially cast-in, but its gap was improved when time was fully passed. 3. After mixing blast-furnace slag and fly-ash as substitute material, the result showed that the modulus of elasticity against freezing & melting was improved according to mixing blast-furnace slag and also increased in accordance with increasing pulverulent-body volume. 4. According to increasing the mixing volume of fly-ash, the durability factor was deteriorated because compressive strength became lower as well as air content was decreased when it was initially case-in. 5. The minimum air content to secure durability was 3.7%, for that reason, we had better secure admixture such as air entraining agent when cast-in high-flowable concrete.

Pd 나노입자의 자가 회복이 가능한 지능형 페로브스카이트 산화물 음극의 직접 탄화수소계 SOFC 성능 평가 (Self-Regeneration of Intelligent Perovskite Oxide Anode for Direct Hydrocarbon-Type SOFC by Nano Metal Particles of Pd Segregated)

  • 오미영;;신태호
    • 한국전기전자재료학회논문지
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    • 제31권5호
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    • pp.345-350
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    • 2018
  • Nanomaterials have considerable potential to solve several key challenges in various electrochemical devices, such as fuel cells. However, the use of nanoparticles in high-temperature devices like solid-oxide fuel cells (SOFCs) is considered problematic because the nanostructured surface typically prepared by deposition techniques may easily coarsen and thus deactivate, especially when used in high-temperature redox conditions. Herein we report the synthesis of a self-regenerated Pd metal nanoparticle on the perovskite oxide anode surface for SOFCs that exhibit self-recovery from their degradation in redox cycle and $CH_4$ fuel running. Using Pd-doped perovskite, $La(Sr)Fe(Mn,Pd)O_3$, as an anode, fairly high maximum power densities of 0.5 and $0.2cm^{-2}$ were achieved at 1,073 K in $H_2$ and $CH_4$ respectively, despite using thick electrolyte support-type cell. Long-term stability was also examined in $CH_4$ and the redox cycle, when the anode is exposed to air. The cell with Pd-doped perovskite anode had high tolerance against re-oxidation and recovered the behavior of anodic performance from catalytic degradation. This recovery of power density can be explained by the surface segregation of Pd nanoparticles, which are self-recovered via re-oxidation and reduction. In addition, self-recovery of the anode by oxidation treatment was confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM).