• Title/Summary/Keyword: Alternative materials

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Small Molecular Solar Cells toward Improved Efficiency and Stability

  • Kim, Ji-Hwan;Kim, Hyo-Jeong;Jeong, Won-Ik;Kim, Tae-Min;Lee, Yeong-Eun;Kim, Se-Yong;Kim, Jang-Ju
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.73-73
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    • 2011
  • We will report a few methods to improve the efficiency and stability in small molecule based organic solar cells, including the formation of bulk heterojunctions (BHJs) through alternative thermal deposition (ATD), the use of a micro-cavity structure and interface modifications. By ATD which is a simple modification of conventional thermal evaporation, the thicknesses of alternative donor and acceptor layers were precisely controlled down to 0.1 nm, which is critical to form BHJs. The formation of a BHJ in copper(II) phthalocyanine (CuPc) and fullerene (C60) systems was confirmed by AFM, GISAXS and absorption measurements. From analysis of the data, we found that the CuPc|C60 films fabricated by ATD were composed of the nanometer sized disk shaped CuPc nano grains and aggregated C60, which explains the phase separation of CuPc and C60. On the other hand, the co-deposited CuPc:C60 films did not show the existence of separated CuPc nano grains in the CuPc:C60 matrix. The OPV cells fabricated using the ATD method showed significantly enhanced power conversion efficiency compared to the co-deposited OPV cells under a same composition [1]. We will also present by numerical simulation that adoption of microcavity structure in the planar heterojunction can improve the short circuit current in single and tandem OSCs [2]. Interface modifications also allowed us to achieve high efficiency and high stability OSCs.

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Developing the Total Quality Management System of Teaching and Learning Materials (교수·학습자료 질 관리 시스템의 개발)

  • Kang, Shin-Cheon
    • The Journal of Korean Association of Computer Education
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    • v.7 no.4
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    • pp.121-129
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    • 2004
  • If we followed to be based on the result of survey for researching on the actual condition about e-Learning of the MOE(2004), the critical problem has been suggested managing the quality of teaching and learning materials(37.68%(1775/4717)). If we also reviewed the research of the KICE(2002), the superior material's rate of 70,000 teaching and learning materials of the web site, the educational organization, and teachers was 8.7%. There was some suggestions about the quality problem of the teaching and learning material, but there wasn't the alternative policy: there wasn't the systemic program for managing the message quality of teaching and learning materials. The purpose of this study was to develop the alternative system for managing the message quality of teaching and learning materials. The alternative system of this study's result will be the basic to build the system for managing the message quality of teaching and learning materials. I expect that my system will be the useful tool for managing the message quality of teaching and learning materials.

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A Study on the Support System of Alternative Materials for College Students with Visual Impairment (시각장애대학생을 위한 대체자료 지원체계에 관한 연구)

  • Suh, Hye-Ran;Kang, Eun-Yeong
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.26 no.4
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    • pp.5-30
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    • 2015
  • The attention to higher education of individuals with disabilities has been increased. But, there is no concern for successful university life of students with visual impairment. The purpose of this study is to propose systematic learning-support systems for enhancing the rights of college students with visual impairment in accessing and using library materials. To accomplish the purpose of this study, the current states of alternative material system for those with visual impairment and use behavior of college students with visual impairment in Korea were analyzed. This study concluded with the following strategies for constructing the systematic support system for the alternative materials for college students with visual impairment: 1) improvement of The National Library for Individuals with Disabilities' function; 2) empowerment of service center for student with disabilities in University through strengthening network; 3) technical and systematic improvement for copyright protection.

Flyash를 이용한 일일복토재의 포설 사례 연구

  • 박상현;한완수;이재영
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2002.09a
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    • pp.386-389
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    • 2002
  • It may be necessary to apply a daily fever to operate the municipal solid waste landfill. The daily cover helps to control nuisance factors such as the escape of odors, dusts and airborne emissions, and can control the population of disease vectors. Also it may be reduce the infiltration of rain, decreasing the generation of leachate and the potential for surface water and groundwater contamination. Because of its usual availability and traditional usage as the municipal solid waste landfill, soil remains as the most common daily cover material. However, soil tends to reduce the volume of dumping waste c;3pacity in the landfill, it also reduces a period of using in the landfill. Therefore, it is necessary to research about Alternative Daily Cover Materials (ADCMs) because of the limitation of landfill sites. Recently, The types of ADCMs are classified into geosynthetics, forms, spray-ons, indigenous materials. In this study, the authors have tested the spray type of Alternative Daily Cover(ADC) using by flyash, alum with cement. The development. of ADCMs will be highly effective in terms of prolongation using landfill.

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Plasma Aided Process As Alternative to Hard Chromium Electroplating

  • Kwon, Sik-Chol;Lee, K.H.;Kim, J.K.;Kim, M.;Lee, G.H.;Nam, K.S.;Kim, D.;Chang, D.Y.
    • Journal of the Korean institute of surface engineering
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    • v.36 no.1
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    • pp.48-58
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    • 2003
  • This paper will present an overview of toxicity of hexavalent chromium as well as effort for its replacement by a wide spectrum of alternative materials and technologies. Cr-based materials such as trivalent electrodeposit will be one of strong candidates for hard chromium by surface modification of its surface hardness. Ni-base alloy deposits has proved its application in specific mold for glass. HVOF has been studied in aircraft and military sector. There are still under way of development for commercially available alternatives. To date, no single coating has been identified as universal process as comparable to conventional hard chromium electroplating.

CIGS Thin Film Solar Cells by Electrodeposition

  • Saji, Viswanathan S.;Lee, Sang-Min;Lee, Chi-Woo
    • Journal of the Korean Electrochemical Society
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    • v.14 no.2
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    • pp.61-70
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    • 2011
  • Thin film solar cells with chalcopyrite $CuInSe_2/Cu(In,Ga)Se_2$ absorber materials, commonly known as "CIS/CIGS solar cells" have recently attracted significant research interest as a potential alternative energy-harvesting system for the next generation. Among the different deposition techniques available for the CIGS absorber layer, electrodeposition is an effective and low cost alternative to vacuum based deposition methods. This article reviews progress in the area of CIGS solar cells with an emphasis on electrodeposited absorber layer. Existing challenges in fabrication of stoichiometric absorber layer are highlighted.

Identification of B52-dependent Gene Expression Signature and Alternative Splicing Using a D. melanogaster B52-null Mutant

  • Hong, Sun-Woo;Jung, Mi-Sun;Kim, Eun-Kyung;Lee, Dong-Ki;Kim, So-Youn
    • Bulletin of the Korean Chemical Society
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    • v.30 no.2
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    • pp.323-326
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    • 2009
  • SR proteins are essential splicing regulators and also modulate alternative splicing events, which function both as redundant and substrate-specific manner. The Drosophila B52/SRp55, a member of the SR protein family, is essential for the fly development in vivo, as deletion of B52 gene results in lethality of animals at the second instar larval stage. Identification of the splicing target genes of B52 thus should be crucial for the understanding of the specific developmental role of B52 in vivo. In this study, we performed whole-genome DNA microarray experiments with a B52- knock-out animal. Analysis of the microarray data not only provided the B52-dependent gene expression signature, but also revealed a larval-stage specific, alternative splicing target gene of B52. Our result thus provides a starting point to understand the essential function of B52 at the organismal level.

Advancements in Sustainable Plant-Based Alternatives: Exploring Proteins, Fats, and Manufacturing Challenges in Alternative Meat Production

  • Minju Jung;YouKyeong Lee;Sung Ok Han;Jeong Eun Hyeon
    • Journal of Microbiology and Biotechnology
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    • v.34 no.5
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    • pp.994-1002
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    • 2024
  • The rise in plant-based food consumption is propelled by concerns for sustainability, personal beliefs, and a focus on healthy dietary habits. This trend, particularly in alternative meat, has attracted attention from specialized brands and eco-friendly food companies, leading to increased interest in plant-based alternatives. The dominant plant-based proteins, derived mainly from legumes, include soy protein isolates, which significantly impact sensory factors. In the realm of plant-based fats, substitutes are categorized into fat substitutes based on fats and fat mimetics based on proteins and carbohydrates. The production of these fats, utilizing gums, emulsions, gels, and additives, explores characteristics influencing the appearance, texture, flavor, and storage stability of final plant-based products. Analysis of plant-based proteins and fats in hamburger patties provides insights into manufacturing methods and raw materials used by leading alternative meat companies. However, challenges persist, such as replicating meat's marbling characteristic and addressing safety considerations in terms of potential allergy induction and nutritional supplementation. To enhance functionality and develop customized plant-based foods, it is essential to explore optimal combinations of various raw materials and develop new plant-based proteins and fat separation.