• Title/Summary/Keyword: Active sites

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A Study of Health & Disaster Monitoring Measurement using Ubiquitous Active Communication Digital Datalogger System for Railway Structures (유비쿼터스 기반 통신의 철도구조물에 대한 재난감지용 능동형 데이터로거 시스템 연구)

  • Lee, Seong-Won
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.470-475
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    • 2011
  • The objective of this study is the developement health & disaster monitoring measurement using ubiquitous active communication digital datalogger system for monitoring measurement of railway construction sites. For the replacement of current passive data communication, ubiquitous active communication digital datalogger system is studied for the first time with in a country. Therefore data communication method and analyzing program of automatic measurement data is developed for the global positioning automatic digital datalogger system. The results of this study will be using both real time automatic monitoring measurement and health & disaster monitoring measurement of railway structures.

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The Study on the Security Model for ActiveX Control Management through Security Authentication (보안 인증을 통한 ActiveX Control 보안 관리 모델에 관한 연구)

  • Park, Sung-Yong;Moon, Jong-Sub
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.19 no.6
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    • pp.113-119
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    • 2009
  • In recent years, to provide visitors with the various and dynamic services, many ActiveX Controls are developed and distributed in most of the web sites such as e-Government Internet banking Portal in Korea. However, unsecure ActiveX Controls may be critical security threats on Internet User. Although hacking incidents increase sharply for these vulnerable ActiveX Controls, there are not enough national security actions or policies. Thus, in this paper we propose the technical method to design 'Security model for ActiveX Control Managemnet through Security Authentication' to be able safe and useful security management in three aspects of development distribution using.

An analysis of consumers자 reliability and satisfaction for anti-site and willingness to revisit it (안티 사이트에서의 소비자 신뢰, 소비자만족 및 재방문의사에 대한 분석)

  • 허경옥
    • Journal of Family Resource Management and Policy Review
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    • v.7 no.1
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    • pp.77-89
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    • 2003
  • This study examines factors to influence consumers’reliability, and satisfactions for consumer anti-site, and willingness to visit that site again among consumers utilizing anti-sites. According to the results of this study, first, male, consumers utilizing electronic commerce were more likely to visit anti-site. Consumers were more likely to write their own message and reply other consumers’message in anti-site when they have purpose to complain about their dissatisfaction regarding the process of purchase behavior. Second, consumer's satisfaction is higher in cases of consumers having higher recognition of necessity of anti-site, visiting not required to affiliate the members of anti-site, and being reliable sites. Third, consumers were more likely to use anti-site again when they had higher recognition in the necessity of anti-site and were more satisfied. Finally, in order to facilitate the utilization of anti-sites, those solutions include systematic classification and management of writings listed in the site, active management of the site managers, solutions for criticisms on the writings listed and lack of objectivity of information provided, and active searches for solutions rather than listing of writings on discontents and resistance.

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Poly-3,4-dihydroxybenzaldehyde Modified with 3,4-dihydroxybenzoic acid for Improvement of Electrochemical Activities

  • Cha Seong-Keuck
    • Journal of the Korean Electrochemical Society
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    • v.7 no.4
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    • pp.167-172
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    • 2004
  • 3,4-dihydroxybenzaldehyde(3,4-DHB) was oxidatively el electropolymerized on glassy carbon (GC) electrodes to prepare CC/p-3,4-DHB type electrodes, which were subsequently modified with 3,4-dihydroxybenzoic acid(3,4-DHBA) using 0.05M HCI as a catalyst. The esterification reactions were performed between -OH sites on the polymeric film surface of the p-3,4-DHB and the -COOH sites within the 3,4-DHBA molecules in solution. These reactions had a rate constant value of $1.1\times10^{-1}\;s^{-1}$ for the esterification step as obtained from the first-order rate constant in the solution. The electrochemical responses of the GC/p-3,4-DHB-3,4-DHBA electrodes exert an influence upon the buffer solution, its pH and applied potential ranges. The redox process of the electrode was more easily controlled by charge transfer kinetics than that of the CC/p-3,4-DHB. The modified electrodes had redox active sites that were 10 times more active than those present before modification. The electrical admittance of the modified electrodes was also three times higher than that of the unmodified electrodes. After being annealed in ethanol for 20 hrs the electrodes brought about a 3.3 times greater change of water molecules in the redox reaction. The modified electrodes are stable in the potential range of 0.4 to 0.55V.

DNAse 1 Hypersensitive Sites of Lung Specific Transcription Factor Gene (폐특이 전사조절 유전자의 DNAse 1 Hypersensitive Sites)

  • Lee, Yong-Chul
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.6
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    • pp.879-886
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    • 2000
  • Background : Thyroid Transcription Factor-1(TTF-1) acts as a tissue specific transcription factor in the regulation of lung specific gene expression and as morphogenic protein during lung organogenesis. Currently, there is very little information on the cis-acting sequences and transcription factors that direct the TTF-1 gene expression. DNAse 1 hypersensitive (DH) sites represent a marker for active or potentially active chromatin and are likely to be especially important in gene regulation, being associated with many DNA sequences that regulate gene expression. It is clear that DH regions correlate with genetic regulatory loci and binding for sequence-specific DNA-binding proteins. Methods : We have used DH site assays to identify putative distal regulatory elements in H441 lung adenocarcinoma cells, which express the TTF-1 gene and HeLa cells. Results : There are four DH sites 5' of the TTF-1 gene. These sites are located at base pair approximately +150, -450, -800, and -1500 from the start of transcription. Conclusion : These data suggest that there may be at least one intragenic site and regulatory region 5' prime to the promotor region.

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CNDO/2 MO Calculations for Catalytic Acidity of V-silicalite (실리카에 담지된 바나듐 촉매의 산성도에 대한 CNDO/2 분자궤도론적 계산)

  • Kim, Myung-Chul
    • Applied Chemistry for Engineering
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    • v.5 no.2
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    • pp.357-360
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    • 1994
  • The CNDO/2 calculations have been applied on cluster models for the representative active sites in V-silicalite to get Wiberg bond orders, LUMO energies and total energies. The B acidities of suggested models were investigated in terms of O-H bond orders. And the calculated LUMO energies showed the L acidities of the active sites. The structural stabilities of cluster models were also explained in terms of total energies.

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A Qualitative Study on the Evaluation on tm he Consumers' Voluntary Anti-sites on On-line from the People Concerned (소비자 자발적 안티 사이트 관련자들의 안티사이트 평가: 질적연구방법의 적용)

  • Choi, Young-Won;Lee, Eun-Hee
    • Korean Journal of Human Ecology
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    • v.16 no.4
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    • pp.783-800
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    • 2007
  • This study examined the evaluation on the consumers' voluntary anti-sites on on-line from the people concerned, such as the people of an enterprise, a consumer organization, and the consumer. We collected the data using in-depth interview of qualitative analysis. The in-depth interviews were carried out for about two hours in each respondent. Total 15 respondents, 5 in each part of three parts such as an enterprise, a consumer organization, and the consumer, were answered a interview. The data was analysed by content analysis method. As the result of this study, the people concerned to enterprises answered that anti-sites helped the enterprises through the objective and the constructive criticism. The consumers participating in the anti-sites also answered that the existence of anti-sites helped the companies to know the complaint and the dissatisfaction with their goods or services. We suggest the followings for the desirable consumers' voluntary anti-sites through this study. First, the companies need to recognize that the anti-sites help the companies because the anti-sites give the companies the information of improving the product and the corporate management. Second, people concerned to the consumer organizations need to take a neutral role so that the consumer members of anti-sites demand a proper compensation to the companies and receive the reasonable compensation. Third, the anti-sites' managers should give information to the consumer members of the anti-sites continuously, operate the anti-sites actively such as answering a question and managing their members. Fourth, the consumer members of anti-sites should have active attitude in participating in an anti-sites from exchanging various information to uploading their information.

Binder-Free Synthesis of NiCo2S4 Nanowires Grown on Ni Foam as an Efficient Electrocatalyst for Oxygen Evolution Reaction

  • Patil, Komal;Babar, Pravin;Kim, Jin Hyeok
    • Korean Journal of Materials Research
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    • v.30 no.5
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    • pp.217-222
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    • 2020
  • The design and fabrication of catalysts with low-cost and high electrocatalytic activity for the oxygen evolution reaction (OER) have remained challenging because of the sluggish kinetics of this reaction. The key to the pursuit of efficient electrocatalysts is to design them with high surface area and more active sites. In this work, we have successfully synthesized a highly stable and active NiCo2S4 nanowire array on a Ni-foam substrate (NiCo2S4 NW/NF) via a two-step hydrothermal synthesis approach. This NiCo2S4 NW/NF exhibits overpotential as low as 275 mV, delivering a current density of 20 mA cm-2 (versus reversible hydrogen electrode) with a low Tafel slope of 89 mV dec-1 and superior long-term stability for 20 h in 1 M KOH electrolyte. The outstanding performance is ascribed to the inherent activity of the binder-free deposited, vertically aligned nanowire structure, which provides a large number of electrochemically active surface sites, accelerating electron transfer, and simultaneously enhancing the diffusion of electrolyte.

Electronic structure and catalytic reactivity of model oxide catalysts

  • Kim, Yu-Gwon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.35-35
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    • 2010
  • Understanding the mechanistic details of heterogeneous catalytic reactions will provide a way to tune the selectivity between various competing reaction channels. In this regard, catalytic decomposition of alcohols over the rutile $TiO_2$(110) surface as a model oxide catalyst has been studied to understand the reaction mechanism employing the temperature-programmed desorption (TPD) technique. The $TiO_2$(110) model catalyst is found to be active toward alcohol dehydration. We find that the active sites are bridge-bonded oxygen vacancies where RO-H heterolytically dissociates and binds to the vacancy to produce alkoxy (RO-) and hydroxyl (HO-). Two protons adsorbed onto the bridge-bonded oxygen atoms (-OH) readily react with each other to form a water molecule at ~500 K and desorb from the surface. The alkoxy (RO-) undergoes decomposition at higher temperatures into the corresponding alkene. Here, the overall desorption kinetics is limited by a first-order decomposition of intermediate alkoxy (RO-) species bound to the vacancy. We show that detailed analysis on the yield and the desorption temperatures as a function of the alkyl substituents provides valuable insights into the reaction mechanism. After the catalytic role of the oxygen vacancies has been established, we employed x-ray photoelectron spectroscopy to further study the surface electronic structure related to the catalytically active defective sites. The defect-related state in valence band has been related to the chemically reduced $Ti^{3+}$ defects near the surface region and are found to be closely related to the catalytic activity of the $TiO_2$(110) surface.

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Immobile Artificial Metalloproteases

  • Kim, Myoung-Soon;Suh, Jung-Hun
    • Bulletin of the Korean Chemical Society
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    • v.26 no.12
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    • pp.1911-1920
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    • 2005
  • Effective artificial metalloproteases have been designed by using cross-linked polystyrene as the backbone. Artificial active sites comprising Cu(II) complexes as the catalytic site and other metal centers or organic functionalities as binding sites were synthesized. The activity of Cu(II) centers for peptide hydrolysis was greatly enhanced on attachment to polystyrene. By placing binding sites in proximity to the catalytic centers, the ability to hydrolyze a variety of protein substrates at selected cleavage sites was improved. Thus far, the most advanced immobile artificial proteases have been obtained by attaching the aldehyde group in proximity to the Cu(II) complex of cyclen.