• Title/Summary/Keyword: Key Barrier

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Analysis of Alternative Formats Development Policy for the Disabled Persons in the Major Countries (주요 국가의 장애인용 대체자료 개발정책 분석)

  • Yoon, Hee-Yoon
    • Journal of Korean Library and Information Science Society
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    • v.41 no.1
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    • pp.29-49
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    • 2010
  • In an increasingly digital world, knowledge and information accessibility is becoming a key factor to personal, professional and national development. But only 5% of the world's publishing output is made accessible in alternative formats for people who cannot use print. People with disabilities say that the biggest barrier to access to the material they want or need to read is a lack of accessible information. This study aims to analyze the development policies(governance and role, funding and support, production and distribution system, etc.) of alternative formats for people with disabilities in major countries(Australia, Canada, Japan, Korea, Sweden, UK, and USA). And result of this preliminary study will be used as background information for development of the national plan and role model for production and distribution of the alternative formats in Korea.

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Improvement of Permeability to Organic Solvent in Escherichia coli for a Toxicity Biosensor

  • Bae, Hee-Kyung;Shin, Pyong-Kyun;Song, Bang-Ho
    • Proceedings of the Korean Society for Applied Microbiology Conference
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    • 2001.06b
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    • pp.14-16
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    • 2001
  • The outer membrane (OM) of gram-negative bacteria acts as an effective permeability barrier against noxious agents including several antibiotics and organic solvents, and lipopolysaccharide (LPS) is the key molecule for this function. Outer membrane modified mutants (Ml-166, M2-42, M3-21) of E. coli DH5$\alpha$/pBSl were selected through a mutation using EMS (ethyl-methane-sulfonate). Among the selected mutants, M3-21 was twice as sensitive as LumisTo $x^{ }$ to benzene and M2-41 was 8 times as sensitive as LumisTo $x^{ }$ to toluene. To identify the structural change in the membrane by mutation, the relative cell surface hydrophobicities and the absorption of the crystal violet to the organisms were measured. All the mutants absorbed more crystal violet than their parent and the absorption of crystal violet increased in cell walls as carbohydrate of lipopolysaccharide decreased. When the cell surface hydrophobicities of DH5/pBSl and its mutants were measured by the BATH, the hydrophobicities of mutants increased compared to their parent in several organic solvents. The difference of lipopolysaccharide between DH5/pBSl and its mutants was identified by various ways such as the SDS-PAGE gel, the screening of LPS molecular weights, the mass spectrometry, and MALDI-TOF.F.

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Functional Roles of the Aromatic Residues in the Stabilization of the [$Fe_4S_4$] Cluster in the Iro Protein from Acidithiobacillus ferrooxidans

  • Zeng, Jia;Liu, Qing;Zhang, Xiaojian;Mo, Hongyu;Wang, Yiping;Chen, Qian;Liu, Yuandong
    • Journal of Microbiology and Biotechnology
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    • v.20 no.2
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    • pp.294-300
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    • 2010
  • The Iro protein is a member of the HiPIP family with the [$Fe_4S_4$] cluster for electron transfer. Many reports proposed that the conserved aromatic residues might be responsible for the stability of the iron-sulfur cluster in HiPIP. In this study, Tyr10 was found to be a critical residue for the stability of the [$Fe_4S_4$] cluster, according to site-directed mutagenesis results. Tyr10, Phe26, and Phe48 were essential for the stability of the [$Fe_4S_4$] cluster under acidic condition. Trp44 was not involved in the stability of the [$Fe_4S_4$] cluster. Molecular structure modeling for the mutant Tyr10 proteins revealed that the aromatic group of Tyr10 may form a hydrophobic barrier to protect the [$Fe_4S_4$] cluster from solvent.

A Study for Stable End Point Detection in 90 nm WSix/poly-Si Stack-down Gate Etching Process (90 nm급 텅스텐 폴리사이드 게이트 식각공정에서 식각종말점의 안정화에 관한 연구)

  • Ko, Yong-Deuk;Chun, Hui-Gon;Lee, Jing-Hyuk
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.3
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    • pp.206-211
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    • 2005
  • The device makers want to make higher density chips on the wafer through scale-down. The change of WSix/poly-Si gate film thickness is one of the key issues under 100 nm device structure. As a new device etching process is applied, end point detection(EPD) time delay was occurred in DPS+ poly chamber of Applied Materials. This is a barrier of device shrink because EPD time delay made physical damage on the surface of gate oxide. To investigate the EPD time delay, the experimental test combined with OES(Optical Emission Spectroscopy) and SEM(Scanning Electron Microscopy) was performed using patterned wafers. As a result, a EPD delay time is reduced by a new chamber seasoning and a new wavelength line through plasma scan. Applying a new wavelength of 252 nm makes it successful to call corrected EPD in WSix/poly-Si stack-down gate etching in the DPS+ poly chamber for the current and next generation devices.

Viable Alternatives to in vivo Tests for Evaluating the Toxicity of Engineered Carbon Nanotubes

  • Kwon, Soon-Jo;Eo, Soo-Mi
    • Journal of Environmental Health Sciences
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    • v.38 no.1
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    • pp.1-7
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    • 2012
  • Carbon nanotubes (CNTs) stand at the frontier of nanotechnology and are destined to stimulate the next industrial revolution. Rapid increase in their production and use in the technology industry have led to concerns over the effects of CNT on human health and the environment. The prominent use of CNTs in biomedical applications also increases the possibility of human exposure, while properties such as their high aspect ratio (fiber-like shape) and large surface area raise safety concerns for human health if exposure does occur. It is crucial to develop viable alternatives to in vivo tests in order to evaluate the toxicity of engineered CNTs and develop validated experimental models capable of identifying CNTs' toxic effects and predicting their level of toxicity in the human respiratory system. Human lung epithelial cells serve as a barrier at the interface between the surrounding air and lung tissues in response to exogenous particles such as air-pollutants, including CNTs. Monolayer culture of the key individual cell types has provided abundant fundamental information on the response of these cells to external perturbations. However, such systems are limited by the absence of cell-cell interactions and their dynamic nature, which are both present in vivo. In this review, we suggested two viable alternatives to in vivo tests to evaluate the health risk of human exposure to CNTs.

The latest study tendency in mouse model of skin pruritus - Mainly on scratching behavior model (피부 소양 마우스 모델의 최근 연구 동향 -Scratching behavior model을 중심으로)

  • Kim, Keoo-Seok;Kim, Yoon-Bum
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.20 no.2 s.33
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    • pp.142-150
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    • 2007
  • Objectives : This study was carried out to investigate the latest study tendency in mouse model of skin pruritus published since 2005 and to arrange various experimental methods. Methods : We examined the journal(such as Experimental dermatology and British journal of dermatology) and in Pubmed since 2005, regarded pruritus and scratching behavior model as key words. Results and Conclusion : 1. BALB/c, hairless, NC/Nga and ICR mice were the most used in scratching behavior model. According to scratching-induced agents. we need to select experimental mice. 2. There are various methods inducing skin pruritus; by cohabitation with NC/Nga mice having severe skin lesions, by injection intradermally(or subcutaneously) with agent inducing inflammation, by inducing contact dermatitis with TNCB, TNFB, destruction of skin barrier and by transgenic mice. 3. Injection intradermally(or subcutaneously) with agent inducing inflammation is the most used out of methods inducing skin pruritus. Compound 48/80, histamine, substance P and others(chloroquine, serotonin, carrageenin, TPA etc.) were included in agents inducing inflammation and pruritus in skin pruritus model. 4. Video camera, SCLABA system, MicroAct and acoustic evaluation system were included in evaluation methods of scratching behavior mouse model.

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A Study on the Transfer of the Oscillator's Motion Information with 2 Degrees of Freedom;Thermal Boundary Resistance (2자유도 진동계의 운동정보 전달에 관한 연구;경계면열저항)

  • Choi, Soon-Ho;Choi, Hyun-Kye;Jin, Chang-Fu;Kim, Kyung-Kun;Yoon, Seok-Hun;Oh, Cheol
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2005.06a
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    • pp.1102-1107
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    • 2005
  • The analysis of the thermal boundary resistance is very important in the both cases of microscale and macroscale systems because it plays a role of thermal barrier against a heat flow. Especially, since fairly large heat energy is generated in microscale or nanoscale systems with electronic chips, the thermal boundary resistance is a key factor to guarantee the performance of those devices. In this study, the transfer of the oscillator's motion information with 2 degrees of freedom is investigated for clarifying the mechanism of a thermal boundary resistance. We found that the transfer of the oscillator's motion information is defined as a cross-correlation coefficient and the magnitude of it determines the temperature jump over a solid interface. That is, the temperature jump over an interface increases as the magnitude of a cross-correlation coefficient decreases and vice versa.

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Flexible Low Power Consumption Active-Matrix OLED Displays

  • Hack, Mike;Chwang, Anna;Hewitt, Richard;Brown, Julie;Lu, JengPing;Shih, ChinWen;Ho, JackSon;Street, R.A.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07a
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    • pp.609-613
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    • 2005
  • Advanced mobile communication devices require a bright, high information content display in a small, light-weight, low power consumption package. In this paper we will outline our progress towards developing such a low power consumption active-matrix flexible OLED ($FOLED^{TM}$) display. Our work in this area is focused on three critical enabling technologies. The first is the development of a high efficiency long-lived phosphorescent OLED ($PHOLED{TM}$) device technology, which has now proven itself to be capable of meeting the low power consumption performance requirements for mobile display applications. Secondly, is the development of flexible active matrix backplanes, and for this our team are employing poly-Si TFTs formed on metal foil substrates as this approach represents an attractive alternative to fabricating poly-Si TFTs on plastic for the realization of first generation flexible active matrix OLED displays. Unlike most plastics, metal foil substrates can withstand a large thermal load and do not require a moisture and oxygen permeation barrier. Thirdly, the key to reliable operation is to ensure that the organic materials are fully encapsulated in a package designed for repetitive flexing. We also present progress in operational lifetime of encapsulated T-PHOLED pixels on planarized metal foil and discuss PHOLED encapsulation strategy.

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Psychosocial Risks: Is Risk Management Strategic Enough in Business and Policy Making?

  • Langenhan, Melissa K.;Leka, Stavroula;Jain, Aditya
    • Safety and Health at Work
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    • v.4 no.2
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    • pp.87-94
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    • 2013
  • Background: In times of continuous change and volatile markets, organizations are increasingly characterized by downsizing, work intensification, and resource rationalization. This has resulted in diversification, and the emergence of newrisks within the field of occupational health and safety, with an important impact. This paper focuses on one such type of risk in the modern workplace-psychosocial risks. The current study aimed to explore stakeholder perspectives, regarding the extent to which psychosocial risks are incorporated into strategic risk management practices, at both the business and policy level. Methods: Semi-structured interviews were conducted with 14 professionals, representing employer, expert, policy maker, and trade union stakeholder perspectives. Results: It was found that the majority of organizations do not sufficiently, if at all, understand and incorporate psychosocial risks into strategic decision making, whereby the key barrier related to practical difficulties of not knowing how to manage psychosocial risks adequately. Conclusion: The study found that there is a need to close the gap between policy and practice on a number of levels. Future recommendations comprise a policy framework and infrastructure underpinned by educational initiatives, partnerships, and networks to drive a shift in attitudes toward recognizing the duality of the concept of risk (including both potential negative and positive outcomes) and moving beyond simple regulatory compliance.

Perfluorinated Sulfonic Acid Ionomer Membranes for Valued Chemical Production (과불소계 술폰화 이오노머막을 이용한 고부가가치 화학품 제조)

  • Shim, Jae Goo;Park, In Kee;Lee, Chang Hyun
    • Membrane Journal
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    • v.26 no.2
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    • pp.152-158
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    • 2016
  • The Chlor-alkali (CA) membrane cell is a major electrolysis system to produce valued chemicals such as chlorine gas and sodium hydroxide. The CA membrane process has been attracted in the industries, since it has relatively low energy consumption when compared with other CA processes. The key component in CA process is perfluorinated sulfonic acid ionomer membranes, which provide ion-selectivity and barrier properties to produced gases. Unfortunately, there is limited information to determine which factors should be satisfied for CA applications. In this study, the influences of PFSA membranes on CA performances are disclosed. They include ion transport behaviors, gas evolution capability, and chemical/electrochemical resistances under CA operation conditions.