• Title/Summary/Keyword: Activation system

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Cure Kinetics of DGEBA/MDA/HQ-PGE System (DGEBA/MDA/HQ-PGE계의 경화 반응 속도론)

  • Song, Young-Wook;Shim, Mi-Ja;Kim, Sang-Wook
    • Applied Chemistry for Engineering
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    • v.7 no.2
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    • pp.356-361
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    • 1996
  • Cure kinetics of diglycidyl ether of bisphenol A(DGEBA)/4,4'-methylene dianiline(MDA) with hydroquinone-phenyl glycidyl ether(HQ-PGE) as a reactive additive, which was preliminarily synthesized, was investigated by DSC and FT-IR analyses. Kissinger equation and Arrhenius' equation were used to calculate activation energy and pre-exponential factor. When HQ-PGE was added to DGEBA/MDA system, it reduced activation energy of system. When the 5 phr of HQ-PGE was added to DGEBA/MDA system, activation energy was 7.8 kcal/mol by FT-IR analysis and 11.3 kcal/mol by DSC, in comparison with the system without HQ-PGE, activation energy decreased about 30% and 9%, respectively. According to these results, HQ-PGE, introducing agent of this system, acted as a catalyst.

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Activation Volumes of Wall-Motion and Nucleation Processes in Co/Pd Multilayers

  • Choe, Sug-Bong;Shin, Sung-Chul
    • Journal of Magnetics
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    • v.5 no.2
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    • pp.35-39
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    • 2000
  • The correlation between the activation volumes of wall-motion and nucleation processes in Co/Pd multilayers has been investigated. Each activation volume was estimated from the field dependence of the wall-motion speed and the nucleation rate, respectively, based on time-resolved domain patterns grabbed by a MOKE microscope system. Both the activation volumes are changed in the same manner around $0.2\sim1.1\times10^{-17}cm^3$ with changes in the multilayered structure. Interestingly, the correlation between the activation volumes is sensitive to the multilayered structure; the wall-motion activation volume is smaller than the nucleation activation volume for a sample having a smaller number of repeats and a thinner Co-layer thickness, and vice versa. The correlation is closely related with the contrasting reversal modes; the process having the smaller activation volume dominates.

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The Genotoxicity Study of Molinate, an Herbicide, in Bacterial Reversion, in vitro and in vivo Mammalian System

  • Kim, Youn-Jung;Ryu, Jae-Chun
    • Molecular & Cellular Toxicology
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    • v.2 no.3
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    • pp.176-184
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    • 2006
  • The controversy on genotoxicity of molinate, an herbicide, has been reported in bacterial system, and in vitro and in vivo mammalian systems. To clarify the genotoxicity of molinate, we performed bacterial gene mutation test, in vitro chromosome aberration and mouse lymphoma $tk^{+/-}$ gene assay, and in vivo micronucleus assay using bone marrow cells and peripheral reticulocytes of mice. In bacterial gene mutation assay, no mutagenicity of molinate ($12-185{\mu}g/plate$) was observed in Salmonella typhimurium TA 98, 100, 1535 and 1537 both in the absence and in the presence of S-9 metabolic activation system. The clastogenicity of molinate was observed in the presence ($102.1-408.2\;{\mu}g/mL$) of metabolic activation system in mammalian cell system using Chinese hamster lung fibroblast. However, no clastogenicity was observed in the absence ($13.6-54.3\;{\mu}g/mL$) of metabolic activation system. It is suggested that the genotoxicity of molinate was derived some metabolites by metabolic activation. Molinate was also subjected to mouse lymphoma L5178Y $tk^{+/-}$ cells using microtiter cloning technique. In the absence of S-9 mixture, mutation frequencies (MFs) were revealed $1.4-1.9{\times}10^{-4}$ with no statistical significance. However, MFs in the presence of metabolic activation system revealed $3.2-3.4{\times}10^{-4}$ with statistical significance (p<0.05). In vivo micronucleus (MN) assay using mouse bone marrow cells, molinate revealed genotoxic potential in the dose ranges of 100-398 mg/kg of molinate when administered orally. Molinate also subjected to acridine orange MN assay with mouse peripheral reticulocytes. The frequency of micronucleated reticulocytes (MNRETs) induced 48 hr after i.p. injection at a single dose of 91, 182 and 363 mg/kg of molinate was dose-dependently increased as $10.2{\pm}4.7,\;14.6{\pm}3.9\;and\;28.6{\pm}6.3\;(mean{\pm}SD\;of\;MNRETs/2,000\;reticulocytes)$ with statistical significance (p<0.05), respectively. Consequently, genotoxic potential of molinate was observed in in vitro mammalian mutagenicity systems only in the presence of metabolic activation system and in vivo MN assay using both bone marrow cells and peripheral reticulocytes in the dose ranges used in this experiment. These results suggest that metabolic activation plays a critical role to express the genotoxicity of molinate in in vitro and in vivo mammalian system.

Evaluation of tTA-Mediated Gene Activation System on Human Cytomegalovirus and Herpes Simplex Virus Type-1 Infections

  • Choi, Kwang-Hoon;Kim, Ki-Ho;Kim, Hong-Jin
    • Archives of Pharmacal Research
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    • v.23 no.3
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    • pp.257-260
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    • 2000
  • The tetracycline-controlled transactivator (tTA)-mediated gene activation system was examined in virus infected cells to determine its role in the control of gene expression. In the presence of tTA, the gene expression from the tetO-modified minimal promoter was efficiently activated in the uninfected cells, whereas essentially no activation was observed from the only minimal promoter without the seven direct repeats of 42 bp tetO sequences. However, essentially no activation was observed when only the minimal promoter was used, without the seven direct repetitions of the 42 bp tetO sequences. On the other hand, in the infected cells, a substantial background of $\beta$-glucuronidase expression was detected in the absence of tTA, even though tTA stimulated the gene expression by ~7-fold. This background expression indicates that the sequences within or nearby tetO are involved in the background stimulation of the gene expression by HCMV and HSV-1 . These results suggest that the application of the tTA-mediated gene activation system may not be extremely useful for studying the biological roles of HCMV and HSV genes In the viral replicative cycles, because of the basal activity of the gene expression.

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Bike Transportation Activation Policy through Carbon Emission Trading (탄소배출권 거래를 고려한 자전거 활성화 정책)

  • Choi, Jae Soon
    • International Journal of Highway Engineering
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    • v.18 no.6
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    • pp.1-10
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    • 2016
  • OBJECTIVES : Currently, the market for carbon emissions trading has been increasing. In Korea, it is known that traffic mode rate in bike transportation is low. However, if bike transportation system is encouraged and the traffic mode rate is increased, it would be possible to reduce carbon emissions through the trading market. In this study, a practical policy to activate the bike transportation system in Korea will be proposed and verified. METHODS : Past studies regarding bike transportation system in international and domestic metropolitan cities were analyzed. Moreover, detailed reviews on recent carbon emissions trading market were performed. In particular, SWOT analysis on the bike transportation system in Korea and policy topology analysis were conducted. RESULTS : Based on the literature reviews and SWOT analysis, a new bike transportation policy was proposed. Several actual plans to adopt in Korea were proposed. In addition, a new bike transportation policy was analyzed using policy typology model, and a business model related to the cost of implementing the system and CERs were also proposed. CONCLUSIONS : It is concluded that the proposed bike transportation activation policy and several practical plans to connect CERs and a business model including bus, subway, T-money and bike riders to give some incentive were effective and reasonable. It is desired that this study will help Korea to get CERs through bike transportation activation in the future.

Monte carlo estimation of activation products induced in concrete shielding around electron linac used in an X-ray container inspection system (X-ray 컨테이너 화물검색시스템의 전자선형가속기 주변 콘크리트 차폐벽 내 방사화생성물에 대한 몬테카를로법 평가)

  • Cho, Young-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.3
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    • pp.1035-1039
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    • 2010
  • Activation products generated by photoneutrons in concrete shielding wall around electron linac were estimated for a high energy X-ray container cargo inspection system. Monte carlo code, MCNPX2.5.0 was used for reference system of 9MeV fixed type dual-direction container cargo inspection system installed at major harbors in Korea. Activation products inventory generated by photoneutron (n,$\gamma$) reaction are estimated, and then radiation dose rate is calculated from the results.

A Study on Activation of uTradeHub System (uTradeHub 시스템 활성화 방안에 관한 연구)

  • Lee, Sang-Ok;Lim, Cheon-Hyeok
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.51
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    • pp.441-464
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    • 2011
  • It is childhood yet in uTradeHub system practical use. According as company's necessity of cost-saving is increased according to trade terms aggravation such as uncertainty of international money market, commodities prices rise, necessity of e-trade practical use in company is increased. Use is inevitable by state that link with e-Nego and e-B/L service with related presentation e-L/C banks is not made. At the present users are doing specification only service this main point, and practical use activation through public information and marketing about service is needed situation because most of, companies which is not using service, do not know about existence availability of uTradeHub system, usage, availability. This study presented five such as early materialization of user center's link and integration, medium and small enterprises e-trade participation extension, utilization ratio raising through government's public information, e-trade cooperation business activation between the country, electronic documents standardization etc. by prompting competition about practical use of uTradeHub system.

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Study on Improving the System for the Revitalization and Efficient Management of the Local Commercial Area (지역상권 활성화 및 효율적 관리를 위한 제도 개선방안 연구)

  • Kim, Seung-Hee;Kim, Young-Ki
    • Journal of Distribution Science
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    • v.11 no.5
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    • pp.55-62
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    • 2013
  • Purpose - This study aims to determine the problems and limitations of the Commercial Area Activation System, which was created by a special law for promoting traditional markets and shopping districts to revitalize and efficiently manage the central commercial area in different regions. We also suggest different options for its improvement. Research design, data, and methodology - We also look into the problems of which is being promoted as a demonstration project, from the aspects of legal text and guidelines. Results - The current commercial area activation system has several problems. First, the establishment of a comprehensive basic plan on the commercial area activation is not a requirement. Second, the benefit principle should be established to prevent the moral laxity of merchants who serve important roles in the main components of the commercial area activation business when they conduct their business. Third, the current special law constrains the commercial management organization, as under the civil law yields a limitation on finding a profitable business model. Fourth, to efficiently, constructing a system that links the other central government businesses and is needed. into a regional development budget or a budget for funding small businesses that the central government can control, which is effective. Further, we offer some suggestions for medium- and long-term policies. First, an integrated coordination mechanism at the central office level should be installed while setting the basic policy to revitalize the Based on this policy, local governments need a system that exclusively based on the after establishing a comprehensive plan for urban regeneration and getting approval from the integration organization. Second, a system that enables an understanding of the problems with business promotion by monitoring the procedure of supporting projects and regularly assessing business achievements is needed. Third, a plan is needed for resolving conflicts between various interested parties that adopts the commercial area activation system for carrying out a total redevelopment of the commercial area where small shops are densely located. A market maintenance project has been conducted as a means to recover our traditional market, which was economically depressed, and to revive the local economy, but it is mostly conducted in the form of reconstruction or redevelopment and represents the interests of landowners and merchants. Thus, it is most likely to lead to a gradual disappearance of traditional markets. Conclusions - This study looks primarily into the problems that appeared in the legal text or the guidelines regarding the direction of improvement of the commercial area activation business that has been going on as a demonstration project since 2011 and suggests some solutions.

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Effects of Motivational Activation on Processing Positive and Negative Content in Internet Advertisements

  • Lee, Seungjo;Park, Byungho
    • Science of Emotion and Sensibility
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    • v.15 no.4
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    • pp.517-526
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    • 2012
  • This study investigated the impact of individual differences in motivational reactivity on cognitive effort, memory strength (sensitivity) and decision making (criterion bias) in response to Internet ads with positive and negative content. Individual variation in trait motivational activation was measured using the Motivational Activation Measurement developed by A. Lang and her colleagues (A. Lang, Bradley, Sparks, & Lee, 2007). MAM indexes an individual's tendency to approach pleasant stimuli (ASA, Appetitive System Activation) and avoid unpleasant stimuli (DSA, Defensive System Activation). Results showed that individuals higher in ASA exert more cognitive effort during positive ads than individuals lower in ASA. Individuals higher in DSA exert more cognitive effort during negative ads compared to individuals lower in DSA. ASA did not predict recognition memory. However, individuals higher in DSA recognized ads better than those lower in DSA. The criterion bias data revealed participants higher in ASA had more conservative decision criterion, compared to participants lower in ASA. Individuals higher in DSA also showed more conservative decision criterion compared to individuals lower in DSA. The theoretical and practical implications are discussed.

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Cerebral Activation Area Following Oxygen Administration using a 3 Tesla Functional MR Imaging (고 자장 기능적 MR 영상을 이용한 뇌 운동 영역에서 산소 주입에 따른 활성화 영역에 관한 연구)

  • Goo, Eun-Hoe;Kweon, Dae-Cheol
    • Journal of the Ergonomics Society of Korea
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    • v.24 no.4
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    • pp.47-53
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    • 2005
  • This study aim to investigate the effects of supply of oxygen enhances cerebral activation through increased activation in the brain and using a 3 Tesla fMRI system. Five volunteers (right handed, average age of 21.3) were selected as subjects for this study. Oxygen supply equipment that provides 30% oxygen at a constant rate of 15L/min was given using face mask. A 3 Tesla fMRI system using the EPI BOLD technique, and three-pulse sequence technique get of the true axial planes scanned brain images. The author can get the perfusion images of the brain by oxygen inhalation with susceptibility contrast EPI sequence at the volunteers. Complex movement consisted of a finger task in which subjects flexed and extended all fingers repeatedly in union, without the fingers touching each other. Both task consisted of 96 phases including 6 activations and rests contents. Post-processing was done on MRDx software program by using cross-correlation method. The result shows that there was an improvement in performance and also increased activation in several areas in the oxygen method. These finding demonstrates that while performing cognitive tasks, oxygen administration was due to increase of cerebral activation.