• Title/Summary/Keyword: Active sites

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Enriching Natural Monument with User-Generated Mobile Augmented Reality Mashup

  • Shin, Choonsung;Hong, Sung-Hee;Yoon, Hyoseok
    • Journal of Multimedia Information System
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    • v.7 no.1
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    • pp.25-32
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    • 2020
  • This paper proposes a mobile augmented reality mashup for cultural heritage sites such as natural monuments. Several benefits of mobile augmented reality solutions are ideal for preserving and protecting cultural heritage sites. By presenting mobile augmented reality mashup scenarios and mobile mashup framework, we introduce how user-generated multimedia contents can be added. We present two scenarios of Mashup Viewer and Mashup Maker. In Mashup Viewer mode, visitors can create new AR contents using mashup tools for memo, Twitter, images and statistical graphs. In Mashup Maker mode, other visitors also can view the user-generated multimedia AR contents using QR codes as access points. To show feasibility of our approach in mobile platforms, we compare several detection algorithms on PC and mobile platform and report on deployment of our approach in a natural monument museum. With our proposed mashup tools, visitors to the cultural heritage sites can enjoy default AR contents provided by the site administrators and also participate as active content producers and consumers.

STABILIZATION AND RECLAMATION OF OLD LANDFILL DISPOSAL SITES

  • Kemper P.E., Charles C.
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 1996.12a
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    • pp.87-95
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    • 1996
  • The stabilization and reclamation of old disposal sites is becoming more important as significant numbers of disposal sites are closed and abandoned. This technical paper covers an overview of the key issues and methodologies for stabilizing and constructing facilities on old landfills. The slide portion of this presentation also include photographs showing actual construction activities. The key issues that are prevalent in remediating and closing old landfills are : correcting the stormwater flow, leachate breakout, constructing cover caps, controlling landfill gas migration and odors, cleanup groundwater and stabilizing side slopes. Some key techniques for constructing facilities on old landfills include: use of piling, installation of active landfill gas systems, providing LFG barriers under buildings, using utilidors and flexible utility interfaces and designing for site settlement. This Paper provides proven conceptual methods for solving these problems.

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Synfuel Production Technology : Catalyst for Fischer-Tropsch Synthesis (합성액화연료 생산 기술: Fischer-Tropsch 합성용 촉매)

  • Park, Jo-Yong
    • Journal of the Korean Applied Science and Technology
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    • v.30 no.4
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    • pp.726-739
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    • 2013
  • Fischer-Tropsch synthesis (FTS) converts synthesis gas (CO and $H_2$) into longer chain hydrocarbons by a surface polymerization reaction. Cobalt- or iron-based catalysts normally show excellent activity for syngas conversion to petroleum products leading to super clean diesel fuels. The catalytic activities of the catalysts in FTS depend on the number of active sites on the surface. The number of active site was determined by the active metal particle size, loading amount, reduction degree and support-active metal interaction. The investigation adopts new methodology in preparing FT catalyst, which contains the controlled synthesis of active metal. The main focus of this paper is to give an overview of the types of catalysts, also including their preparation and reduction; the types of FT reactors; and also including the reaction conditions.

Chemical Modification of Intracellular Cytosine Deaminase from Chromobacterium violaceum YK 391

  • Kim, Jung;Kim, Tae-Hyun;Yu, Tae-Shick
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.3
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    • pp.180-185
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    • 2005
  • Cytosine deaminase (cytosine aminohydrolase, EC 3.5.4.1) stoichiometrically catalyzes the hydrolytic deamination of cytosine and 5-fluorocytosine to uracil and 5-fluorouracil, respectively. Amino acid residues located in or near the active sites of the intracellular cytosine deaminase from chromobacterium violaceum YK 391 were identified by chemical modification studies. The enzymic activity was completely inhibited by chemical modifiers, such as 1mM NBS, chloramine-T, $\rho-CMB,\;\rho-HMB$ and iodine, and was strongly inhibited by 1mM PMSF and pyridoxal 5'-phosphate. This chemical deactivation of the enzymic activity was reversed by a high concentration of cytosine. Furthermore, the deactivation of the enzymic activity by $\rho-CMB$ was also reversed by 1mM cysteine-HCI, DTT and 2-mercaptoethanol. These results suggested that cysteine, tryptophan and methionine residues might be located in or near the active sites of the enzyme, while serine and lysine were indirectly involved in the enzymic activity. The intracellular cytosine deaminase from C violaceum YK 391 was assumed to be a thiol enzyme.

Solution Plasma Synthesis of BNC Nanocarbon for Oxygen Reduction Reaction

  • Lee, Seung-Hyo
    • Journal of the Korean institute of surface engineering
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    • v.51 no.5
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    • pp.332-336
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    • 2018
  • Alkaline oxygen electrocatalysis, targeting anion exchange membrane alkaline-based metal-air batteries has become a subject of intensive investigation because of its advantages compared to its acidic counterparts in reaction kinetics and materials stability. However, significant breakthroughs in the design and synthesis of efficient oxygen reduction catalysts from earth-abundant elements instead of precious metals in alkaline media still remain in high demand. One of the most inexpensive alternatives is carbonaceous materials, which have attracted extensive attention either as catalyst supports or as metal-free cathode catalysts for oxygen reduction. Also, carbon composite materials have been recognized as the most promising because of their reasonable balance between catalytic activity, durability, and cost. In particular, heteroatom (e.g., N, B, S or P) doping on carbon materials can tune the electronic and geometric properties of carbon, providing more active sites and enhancing the interaction between carbon structure and active sites. Here, we focused on boron and nitrogen doped nanocarbon composit (BNC nanocarbon) catalysts synthesized by a solution plasma process using the simple precursor of pyridine and boric acid without further annealing process. Additionally, guidance for rational design and synthesis of alkaline ORR catalysts with improved activity is also presented.

Situational Causal Model Between LMX, Empowerment and Innovation Behavior (LMX, 임파워먼트 그리고 혁신행동 간의 상황적 인과모형: 내국인과 외국인 근로자의 비교분석을 중심으로)

  • Yu, Byung-Nam
    • Journal of the Korea Safety Management & Science
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    • v.23 no.4
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    • pp.121-133
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    • 2021
  • The composition of human resources in industrial sites is becoming global. In Korea, too, the proportion of foreign members in all industrial fields and production sites is increasing. This is the reason why an approach that reflects this reality is needed in the basic unit of competitive sources. Competitiveness starts with value creation, and this progresses through field innovation. Through empirical analysis of this study, it was analyzed that South Korea members showed active actions and attitudes in developing, promoting, and realizing ideas when they strongly recognized the real meaning of empowerment given by leaders. On the other hand, it was found that foreign members do not know the meaning of empowerment itself, so they are often unable to play an active role in the development, promotion, and realization of ideas. In fact, it was analyzed that foreign members generally did not experience positive interactions with LMX and were exposed to simple tasks and controls. In other words, they are being discriminated against in terms of communication problems, compensation system, and work environment. In particular, this phenomenon is exacerbated in the case of small and medium-sized enterprises (SMEs). Situational response to foreign workers through improvement of LMX and empowerment should be evaluated as a key management task in a situation where productivity improvement and job unit innovation are urgently needed.

Rational Design of Binder-Free Fe-Doped CuCo(OH)2 Nanosheets for High-Performance Water Oxidation

  • Patil, Komal;Jang, Su Young;Kim, Jin Hyeok
    • Korean Journal of Materials Research
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    • v.32 no.5
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    • pp.237-242
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    • 2022
  • Designing and producing a low-cost, high-current-density electrode with good electrocatalytic activity for the oxygen evolution reaction (OER) is still a major challenge for the industrial hydrogen energy economy. In this study, nanostructured Fe-doped CuCo(OH)2 was discovered to be a precedent electrocatalyst for OER with low overpotential, low Tafel slope, good durability, and high electrochemically active surface sites at reduced mass loadings. Fe-doped CuCo(OH)2 nanosheets are made using a hydrothermal synthesis process. These nanosheets are clumped together to form a highly open hierarchical structure. When used as an electrocatalyst, the Fe-doped CuCo(OH)2 nanosheets required an overpotential of 260 mV to reach a current density of 50 mA cm-2. Also, it showed a small Tafel slope of 72.9 mV dec-1, and superior stability while catalyzing the generation of O2 continuously for 20 hours. The Fe-doped CuCo(OH)2 was found to have a large number of active sites which provide hierarchical and stable transfer routes for both electrolyte ions and electrons, resulting in exceptional OER performance.

Effect of Sulfurization on SILAR Synthesized Cobalt Phosphate Hydrate Nanosheets for Oxygen Evolution Reaction

  • Kamble, Girish;Malavekar, Dhanaji;Jang, Suyoung;Kim, Jin Hyeok
    • Korean Journal of Materials Research
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    • v.32 no.10
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    • pp.408-413
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    • 2022
  • The oxygen evolution reaction (OER) is very sluggish compared to the hydrogen evolution reaction (HER). Considering this difference is essential when designing and developing a cost-effective and facile synthesis method for a catalyst that can effectively perform OER activity. The material should possess a high surface area and more active sites. Considering these points, in this work we successfully synthesized sheets of cobalt phosphate hydrate (CP) and sulphurated cobalt phosphate hydrate (CPS) material, using simple successive ionic layered adsorption and reaction (SILAR) methods followed by sulfurization. The CP and CPS electrodes exhibited overpotentials of 279 mV with a Tafel slope of 212 mV dec-1 and 381 mV with a Tafel slope of 212 mV dec-1, respectively. The superior performance after sulfurization is attributed to the intrinsic activity of the deposited well-aligned nanosheet structures, which provided a substantial number of electrochemically active surface sites, speeded electron transfer, and at the same time improved the diffusion of the electrolyte.

Evaluation of Atopy Dermatitis Information on the Internet in Korea

  • Seo, Min-Jun;Park, Jin-Han
    • Journal of Evidence-Based Herbal Medicine
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    • v.1 no.2
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    • pp.1-6
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    • 2008
  • The internet is closely related to the lives of modern people in the 21st Century. Exchanging information with others over the internet in any place through is possible nowadays and such exchanging information has been developed at rapid speed also in the areas of medical care. The internet is an important and rapidly-evolving source of health-related information, and many patients with atopy dermatitis attempt to find information from the internet. This study was performed to investigate the current information available in atopy dermatitis on the internet in Korea. We chose three portal sites and two network communities to analyze the information in which the topic of 'atopy' could be found. Among the 2,024 web sites and 5,613 network communities, 98.2% of the web sites and 71.7% of the communities were related products or service advertisements, and some of them provided incorrect of exaggerated information. There were only 42 web sites and 75 available communities with genuine information, and most of these also presented unattested treatment methods, including alternative therapies. It is quite understandable that patients with atopy dermatitis want to seek information related to their disease and the internet has the potential to be a useful source of information. However, there are no regulations to control the accuracy and quality of information on the internet. We should take an active role in identifying the accuracy and evaluating the quality.

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Improved Bias Stress Stability of Solution Processed ITZO/IGZO Dual Active Layer Thin Film Transistor

  • Kim, Jongmin;Cho, Byoungdeog
    • Proceedings of the Korean Vacuum Society Conference
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    • 2015.08a
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    • pp.215.2-215.2
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    • 2015
  • We fabricated dual active layer (DAL) thin film transistors (TFTs) with indium tin zinc oxide (ITZO) and indium gallium zinc oxide (IGZO) thin film layers using solution process. The ITZO and IGZO layer were used as the front and back channel, respectively. In order to investigate the bias stress stability of ITZO SAL (single active layer) and ITZO/IGZO DAL TFT, a gate bias stress of 10 V was applied for 1500 s under the dark condition. The SAL TFT composed of ITZO layer shows a poor positive bias stability of ${\delta}VTH$ of 13.7 V, whereas ${\delta}VTH$ of ITZO/IGZO DAL TFT was very small as 2.6 V. In order to find out the evidence of improved bias stress stability, we calculated the total trap density NT near the channel/gate insulator interface. The calculated NT of DAL and SAL TFT were $4.59{\times}10^{11}$ and $2.03{\times}10^{11}cm^{-2}$, respectively. The reason for improved bias stress stability is due to the reduction of defect sites such as pin-hole and pores in the active layer.

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