• 제목/요약/키워드: Al-segregation

검색결과 97건 처리시간 0.027초

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
    • /
    • 제6권2호
    • /
    • pp.231-238
    • /
    • 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.

급속응고된 Al-Pb-Cu-Mg 합금의 마모특성에 미치는 미세조직의 영향 (Effect of the Microstructrure of Rapidly Solidified Al-Pb-Cu-Mg on the Wear ProPerty)

  • 김홍물
    • 한국분말재료학회지
    • /
    • 제7권1호
    • /
    • pp.12-18
    • /
    • 2000
  • Effects of the microstrucrure of rapidy solidified Al-Pb-Cu-Mg alloys on the wear investigated. In order to overcome the miscility gap between Al and pb under equilibrium conditions, both in the solid and the liquid states, the alloy were rapidy solidifies to produce them in a segregation-free condition. Although the Pb particles showed relatively fine dispersion in the Al matrix in all the alloys by this process. the Al-16Pb alloy was found to have the most favorable microstructure with discretre with discrete Pb particles of abount 0.5 ${\mu}$m in size. With the addition of Cu and Cu-Mg to Al-16Pb, cellular structures were newly formed; not seen in the binary Al-Pb alloy. Wear properties of the Al-Pb binary alloys measured as a function of the sliding speen, sliding distance, and applied load showed that the Al-16Pb alloy has the best wear resistance, as expected from the fine microstructural features in this alloy. The were resistance of the alloy containing Cu-and Cu-Mg was higher than that of the Al-16Pvb alloy, due to matrix strengthening by precipitation hardeing. The wear mechanism was identified by examining the traces and wear debris.

  • PDF

Cu-In-Ga 금속 전구체의 셀렌화 공정시 발생하는 Ga-segregation 억제에 관한 연구

  • 문동권;안세진;윤재호;곽지혜;조아라;안승규;신기식;윤경훈;이희덕
    • 한국재료학회:학술대회논문집
    • /
    • 한국재료학회 2011년도 춘계학술발표대회
    • /
    • pp.46.2-46.2
    • /
    • 2011
  • CuInSe2 (CIS)계 화합물은 3족 원소(Ga, Al) 또는 6족 원소(S)를 첨가하여 밴드갭 조절이 가능하다는 장점을 가지고 있다. 실제로 동시 증발법으로 Ga을 첨가하여 만든 CuIn0.7Ga0.3Se2(CIGS) 태양전지는 약20%의 높은 효율 보이고 있다. 그러나 최고 효율을 달성한 동시 증발법은 대면적화가 어렵다는 점이 상용화의 걸림돌로 작용하고 있다. 따라서, 그 대안으로 대면적화가 용이한 스퍼터링 및 셀렌화 공정 연구가 진행되고 있다. 그러나 스퍼터링/셀렌화 공정은 Cu-In-Ga 금속 전구체의 셀렌화 시 Ga이 Mo쪽으로 이동하여 CIS/CGS 2개의 상으로 형성된다는 큰 단점을 갖고 있다. 이를 해결하기 위해 셀렌화 후 다시 H2S 기체 분위기에서 열처리하여 표면 밴드갭을 증가시키는 공정이 사용되고 있으나, 이는 열처리 과정이 2번 필요하다는 단점을 갖고 있다. 이러한 단점을 해결하고자 본 연구에서는 금속 전구체의 구조, 셀렌화 공정 조건 및 전구체 내의 상(phase) 조절을 통해 셀렌화 시 Ga segregation을 억제하고자 하였다. 특히 전구체의 상 조절을 통해서 Ga의 이동을 크게 완화시킬 수 있음을 확인하였다.

  • PDF

Functional Requirements to Increase Acceptance of M-Learning Applications among University Students in the Kingdom of Saudi Arabia (KSA)

  • Badwelan, Alaa;Bahaddad, Adel A.
    • International Journal of Computer Science & Network Security
    • /
    • 제21권2호
    • /
    • pp.21-39
    • /
    • 2021
  • The acceptance of smartphone applications in the learning field is one of the most significant challenges for higher education institutions in Saudi Arabia. These institutions serve large and varied sectors of society and have a tremendous impact on the knowledge gained by student segments at various ages. M-learning is of great importance because it provides access to learning through a wide range of mobile networks and allows students to learn at any time and in any place. There is a lack of quality requirements for M-learning applications in Saudi societies partly because of mandates for high levels of privacy and gender segregation in education (Garg, 2013; Sarrab et al., 2014). According to the Saudi Arabian education ministry policy, gender segregation in education reflects the country's religious and traditional values (Ministry of Education, 2013, No. 155). The opportunity of many applications would help the Saudi target audience more easily accept M-learning applications and expand their knowledge while maintaining government policy related to religious values and gender segregation in the educational environment. In addition, students can share information through the online framework without breaking religious restrictions. This study uses a quantitative perspective to focus on defining the technical aspects and learning requirements for distributing knowledge among students within the digital environment. Additionally, the framework of the unified theory of acceptance and use of technology (UTAUT) is used to modify new constructs, called application quality requirements, that consist of quality requirements for systems, information, and interfaces.

분사주조공정에 의하여 제조된 Al-Pb 과편정합금의 조직특성 (Microstructural Characteristics of Al-Pb Hyper-Monotectic Alloys Produced by Spray Cast Deposition Process)

  • 배차헌;정해용;박흥일;김창업;이성렬
    • 한국주조공학회지
    • /
    • 제12권4호
    • /
    • pp.346-354
    • /
    • 1992
  • In Al-Pb monotectic alloys Pb particles are difficult to uniformly distribute over the Al matrix because of the gravity segregation of pb element. Therefore the effects of centrifugally spray casting process on microstructures and distributions of Pb particle were investigated. As the preform thickened the sine of Pb particle became larger, the amount of porosity became lower and microstructures showed the change from spray-deposition microstructures in the lower part of the preform to spray-casting microstructures in the upper part of it. The size of Pb particles, amount of porosity and splat layer boundaries in hot forged preform showed still less than of as-deposited preform.

  • PDF

과공정 Al-Si합금의 원심주조시 용탕온도와 금형회전수가 경사기능 조직에 미치는 영향에 대한 해석적 고찰 (A Numerical Study of the Effect of Casting Temperature and Rotational Frequency of Mold on the Functionally Graded Microstructure in Centrifugal Casting of Hyper-eutectic Al-Si Alloy)

  • 박정욱;김헌주
    • 한국주조공학회지
    • /
    • 제29권2호
    • /
    • pp.78-85
    • /
    • 2009
  • Functionally graded microstructure of centrifugal cast Al-Si alloy, especially distribution of primary Si particles according to the changes of melt pouring temperature and rotation frequency was investigated by numerical simulation. Moving velocity of Si particles increased as the melt pouring temperature and rotational frequency of mold increased. Therefore, segregation tendency of primary Si particles toward inner side of cylindrical sample increased as the melt pouring temperature and rotational frequency of mold increased. Rich distribution region of particles was located at 0.9, 0.7, 0.4 mm from inner surface of cylindrical sample under the centrifugal cast condition of $750^{\circ}C$ melt pouring temperature and 1500, 2000 and 2500 rpm mold rotational frequencies, respectively, by numerical simulation.

압출성 향상을 위한 고강도 7000계 알루미늄 합금의 제조 및 압출한계선도 (Manufacture of 7000 Al Alloy with Superior Extrudability and Its Extrusion Limit Diagram)

  • 함현욱;김병민;조훈;조형호
    • 소성∙가공
    • /
    • 제8권5호
    • /
    • pp.482-490
    • /
    • 1999
  • 7000 series Al alloy with good mechanical properties has been focused with tendency to reduce the components weight of aircraft and automobile. However, it is difficult to manufacture a sound extruded product because of segregation, grain growth, casting defect, surface defect, decreasing extrudability and so on. The objective of this study is to manufacture a new 7000 al alloy more than the extrudability of A7N01 and A7003 through controlling the weight (%) Mg, Zn, Si. Hot extrusion experiments on the axisymmetric rod are performed in 500℃ and also performed analysis of the same process using unmerical analysis method, a coupled rigid-thermoviscoplastic finite element method. Extrusion limit diagram was obtained for the developed alloy by FE-simulation in order to define the relationship of extrusion speed and initial billet temperature.

  • PDF

알루미늄 확산코팅재료의 주기산화 특성에 관한 연구 (A Study on the Cyclic Oxidation Properties of Aluminum Diffusion Coated Materials)

  • 강석철;민경만;김길무
    • 한국표면공학회지
    • /
    • 제32권1호
    • /
    • pp.49-60
    • /
    • 1999
  • The protective oxide scales and coatings formed on high temperature materials must be preserved in high temperature atmosphere. And the thermal stresses induced by thermal cycling and the growth stresses by the formation of oxide scales can cause the loss of adherence and spalling of the oxide scales and coated layers. Among the coating processes Al diffusion coating is favored due to thermochemical stability and superior adherence in an hostile atmosphere. In this study, protective oxide forming element, Al was coated on Ni, Inconel 600 and 690 by diffusion coating process varying coating temperature and time. And the surface stability and adherence of oxide scales formed on those Al diffusion coated materials were evaluated by thermal cycling test. Al diffusion coated specimens showed superior cyclic oxidation resistance compared to bare ones and specimens coated for longer period had better cyclic oxidation resistance, due to the abundant amount of Al in the coated layer. Meanwhile Al diffusion coated Inconel 600 and 690 showed improved cyclic oxidation resistance by the effect of Al in the coated layer and Cr in the substrate. Comparing both Al diffusion coated Inconel 600 and 690, Al diffusion coated Inconel 690 maintained better adhesion between coated layer and substrate by virtue of the bridging effect resulting from the segregation of Cr in the interdiffusion zone.

  • PDF

상계법에 의한 반융용 재료의 항복과 압축거동 (Yield and Compression Behavior of Semi-Solid Material by Upper Bound Method)

  • 최재찬;박형진;박준홍
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1995년도 추계학술대회 논문집
    • /
    • pp.195-198
    • /
    • 1995
  • In Semi-Solid Forging, it is necessary to control the forming variables accurately in order to make near-net-shape products. Generally, the defects of products may occur due to liquid segregation which can be caused by the degree of deformation and condition of friction in Semi-Solid Forging, where the segregation is to be predicted by flow analysis. This paper presents the feasibility of theoretical analysis model using the new yield function which is proposed by Doraivelu et al. to the flow analysis of the semi-solid dendritic Sn-15%Pb alloys instead of adopting the yield criterion of Shima & Oyane which is used by Charreyron and usefulness of the adopted yield function. The distribution of the liquid fraction at various strains in radial direction and the influence of friction are estimated by Upper Bound Method.

  • PDF

알루미나/니켈크롬강 접합체의 미세조직 및 접합강도에 미치는 Ag-Cu-Zr-X 브레이징 합금성분의 영향 (Effect of the Alloying Elements in Ag-Cu-Zr-X Brazing Alloy on the Microstructure and the Bond Strength of $Al_2O_3$/Ni-Cr Steel Brazed Joint)

  • 김종헌;유연철
    • 소성∙가공
    • /
    • 제7권5호
    • /
    • pp.465-473
    • /
    • 1998
  • The effect of alloying elements of Ag-Cu-Zr-X brazing alloy on the microstructure and the bond strength of $Al_2O_3/Ni-Cr$ brazed steel joint was investigated. The reaction layer, $ZrO_2$ (a=5.146 ${\AA}$ , b=5.213 ${\AA}$ , c=5.311 ${\AA}$ )was formed at the interface of $Al_2O_3/Ni-Cr$ steel joint by the redox reaction between alumina and Zr. The addition of An and Al to the Ag-Cu-Zr brazing alloy gave rise to changes in the thickness of the reaction product layer and the morphology of the brazement. Sn caused the segregation of Zr was decreased b Al the $ZrO_2$ layer formed at the Ag-Cu-Zr-Al alloy was thinner than that of $ZrO_2$ formed at the Ag-Cu-Zr-An alloy. The fracture shear strength was strongly dependent on the microstructure of the brazement. Brazing with Ag-Cu-Zr-Sn alloy resulted in a better bond strength than with Ag-Cu-Zr or Ag-Cu-Zr-Al alloy.

  • PDF