• Title/Summary/Keyword: Activation Process

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Evaluation of Structure Development of Xanthan and Carob Bean Gum Mixture Using Non-Isothermal Kinetic Model

  • Yoon, Won-Byong;Gunasekaran, Sundaram
    • Food Science and Biotechnology
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    • v.16 no.6
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    • pp.954-957
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    • 2007
  • Gelation mechanism of xanthan-carob mixture (X/C) was investigated based on thermorheological behavior. Three X/C ratios (1:3, 1:1, and 3:1) were studied. Small amplitude oscillatory shear tests were performed to measure linear viscoelastic behavior during gelation. Temperature sweep ($-1^{\circ}C/min$) experiments were conducted. Using a non-isothermal kinetic model, activation energy (Ea) during gelation was calculated. At 1% total concentration, the Ea for xanthan fraction (${\phi}_x$)=0.25, 0.5, and 0.75 were 178, 159, and 123 kJ/mol, respectively. However, a discontinuity was observed in the activation energy plots. Based on this, two gelation mechanisms were presumed-association of xanthan and carob molecules and aggregation of polymer strands. The association process is the primary mechanism to form 3-D networks in the initial stage of gelation and the aggregation of polymer strands played a major role in the later stage.

An Study of Information Security Observance Priority for Smartwork Activation using AHP(Analytic Hierarch Process) (계층적 분석기법(AHP)을 이용한 스마트워크 활성화를 위한 정보보호 준수사항 우선순위에 관한 연구)

  • Im, Jung-Kil;Kim, Sang-Chul;Lee, Hyeon-Uk
    • Journal of Information Technology Services
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    • v.12 no.2
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    • pp.291-300
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    • 2013
  • In this study, divide by a private enterprise and army, 2 organizations about observed priority item among administrator, service provider, user viewpoint about the information security item for smartwork activation and in 3 steps hierarchic according to AHP technique analyzed and decided priority for information security observance item. As a result, importance difference could confirm identified by administrator, service provider, user viewpoint period of about information security observance item recognizing in a private enterprise and army.

A Study on Activation Scheme of Library Advisory Committee in Korea (우리나라 도서관정책위원회의 활동 분석과 활성화 방안 고찰)

  • Lee, Yong-Nam
    • Journal of the Korean Society for Library and Information Science
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    • v.37 no.4
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    • pp.270-293
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    • 2003
  • The study is to analyze the transition process and various activities of library advisory committees in Korea. In addition the study compared activities of Korean library advisory committees to them of other countries such as USA and UK. It is found that the library advisory committees in Korea has not filled its mission and function since established in 1989. The study suggests several activation plans and scheme for the new library advisory committee.

Regulation of NFAT Activation: a Potential Therapeutic Target for Immunosuppression

  • Lee, Mina;Park, Jungchan
    • Molecules and Cells
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    • v.22 no.1
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    • pp.1-7
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    • 2006
  • The NFAT family of transcription factors plays pivotal roles in the development and function of the immune system. Their activation process is tightly regulated by calcium-dependent phosphatase calcineurin and has been a target of the immunosuppressive drugs cyclosporin A and FK-506. Although the clinical use of these drugs has dramatically increased the success of organ transplantation, their therapeutic use is limited by severe side effects. Recent studies for the calcineurin/NFAT signaling pathway have identified a number of cellular proteins that inhibit calcineurin function. Specific peptide sequences that interfere with the interaction between calcineurin and NFAT have also been characterized. Moreover, diverse approaches to identify small organic molecules that modulate NFAT function have been performed. This review focuses on the recent advances in our understanding of the inhibitory modulation of NFAT function, which may open up the additional avenues for immunosuppressive therapy.

The study on controling curie temperature for the temperature-sensitive Magnetic materical at colling method. (냉각방법에 의한 감온자성체의 큐리온도 조정에 관한 연구)

  • Bae, Jin-Ho;Sin, Yong-Cheol;Kim, Han-Geun
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.828-830
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    • 1988
  • This paper considered temperature-sensitive characteristics on the basis of curie tempeature and quenching method in the process of manufacturing Mn-Cu-Zn Fersite. The results are as follow. Curie tempeature drops according as the content of CuO and ZnO increases. It also decreases according as sintering temperature increases when the content of ZnO in fixed. Curie temperature drops more in quenching than in slow cooling and activation energy diminishes were too. On the basis of curie tempeature, activation energy is greater in paramagnetic region than in ferrimagnetic region. As its voltage-crrent characteristics is similar to that semiconductors, the temperature-sensitive ferrite is expeated to be appied in the area of power electronics.

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Silica Glass Preparation by the Sol-Gel Process and the Temperature Dependence on Changes of Apparent Activation Evergies (졸-겔법에 의한 실리카 유리의 제조와 온도 의존성 및 활성화에너지 변화)

  • 이경희;이병하;오부근;안광훈;김종옥
    • Journal of the Korean Ceramic Society
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    • v.26 no.4
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    • pp.471-478
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    • 1989
  • In this study we investigated the gelation time of sol which containing mixtures of TEOS with H2O, ethanol, HCl in the preparation of monolithic silica glass through Sol-Gel method. In this case apparent activation energies were observed by Arrhenius equation. We investigated the conversion from gel to glass in drying and heat treatment stages using DT-TG, FT-IR, XRD analysis and dried gel conversed to glass by heat treatment up to 85$0^{\circ}C$. The results of this experiment showed that the gelation time of solutions were promoted when increasing the amount of addition of H2O and HCl catalyst for TEOS and high reaction temperature of solution.

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Characterization and Fabrication of Chemically Activated Carbon Fibers with Various Drying Temperatures using OXI-PAN Fibers

  • Moon, Sook-Young;Lee, Byung-Ha;Lim, Yun-Soo
    • Carbon letters
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    • v.8 no.1
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    • pp.30-36
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    • 2007
  • Oxidized PAN (OXI-PAN) fibers were used for the precursors of activated carbon fiber in study. How drying temperature affected the properties of carbon fibers on activating process of carbon fibers was investigated. The specific surface areas of activated carbon fibers have been determined on a series of chemically activated carbons with KOH and NaOH. The experimental data showed variations in specific surface area, iodine and silver adsorptions by the activated carbon fibers. The amount of iodine adsorption increases with increasing specific surface areas in both activation methods. This was because the ionic radius of iodine was smaller than the interior micropore size of activated carbon fibers. Silver adsorbed well in NaOH activated carbon fibers rather than KOH activated carbon fibers in this study.

Activation of Carbon Fiber in $\textrm{CO}_2$ Gas(l)-Activation process of carbon fiber- ($\textrm{CO}_2$ gas를 이용한 탄소섬유의 활성화(I)-탄소섬유의 활성화 과정)

  • No, Jae-Seung;Seo, Dong-Su
    • Korean Journal of Materials Research
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    • v.8 no.2
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    • pp.114-119
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    • 1998
  • 등방성 피치계 탄소섬유를 Co$_{2}$gas중에서 등온산화시켜 활성탄소섬유를 제조하였다. 산화된 섬유의 비표면적은 BET장치를 이용하여 측정하였다. Burn-off가 증가하여도 반응속도는 크게 감소하지 않았으며, 80$0^{\circ}C$와 90$0^{\circ}C$에서 산화된 섬유의 비표면적은 40%-60%의 burn-off에서 급격히 증가하다가 60%이상에서 감소하였다. 110$0^{\circ}C$에서 산화된 시편은 40%이상 burn-off되어도 비표면적은 크게 증가하지 않고 60%를 지나서도 계속해서 표면적이 증가하는 현상을 나타내었다. 100$0^{\circ}C$에서 60.4%의 burn-off가 일어난 산화섬유의 비표면적은 3,614$m^2$/g로 가장 큰 값이 얻어졌다. 등방성 탄소섬유는 미세한 흑연결정립들이 무질서한 배향을 하고 있으며, 미세기공벽으로 작용할 수 있는 결정립층이 많기 때문에 활성탄소섬유 제조를 위한 원료로 적합하다고 판단된다.

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Analysis of problems caused by Big Data's private information handling (빅데이터 개인정보 취급에 따른 문제점 분석)

  • Choi, Hee Sik;Cho, Yang Hyun
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.10 no.1
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    • pp.89-97
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    • 2014
  • Recently, spread of Smartphones caused activation of mobile services, because of that Big Data such as clouding service able to proceed with large amount of data which are hard to collect, save, search and analyze. Many companies collected variety of private and personal information without users' agreement for their business strategy and marketing. This situation raised social issues. As companies use Big Data, numbers of damage cases are growing. In this Thesis, when Big Data process, methods of analyze and research of data are very important. This thesis will suggest that choices of security levels and algorithms are important for security of private informations. To use Big Data, it has to encrypt the personal data to emphasize the importance of security level and selection of algorithm. Thesis will also suggest that research of utilization of Big Data and protection of private informations and making guidelines for users are require for security of private information and activation of Big Data industries.

Study of Export Platform's Activation Plan on Public Services (국내 수출기업 해외시장 진출을 위한 공공서비스 수출플랫폼 활성화 방안에 관한 연구)

  • Bae, Hong Kyun;Choi, Young Jun;Kang, Shin Won
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.61
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    • pp.249-272
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    • 2014
  • The purpose of this study is to seek the revitalization plans of export platform for supporting export enterprise of the domestic public services. To activate the export platform, alternatives to two aspects are required as follows. First of all, a governance plan of export platform should be established. At present, an operation entity of export platform, which is still developing stage, is not yet established. In this situation, even though export platform developed, it will faced with inefficient operation. Therefore, an operation entity and appropriate business model are important to the platform activation. second, to activate platform, it is necessary to support export process of life cycle. In particular, the service, which can support the business strategies setting and project implementation stage, is required. In addition, in order to activate the export platform is need to operate with he government's support program.

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