Ministry of Knowledge economics

Seoul, South Korea

Ministry of Knowledge economics

Seoul, South Korea
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Chung T.,Sejong University | Bae W.,Sejong University | Lee J.,Chonnam National University | Lee W.,Anyang Institute of Technology | Jung B.,Ministry of Knowledge economics
Energy Sources, Part A: Recovery, Utilization and Environmental Effects | Year: 2011

With the fluctuation of international oil prices due to limited conventional petroleum resources, unconventional energy, including bitumen and extra heavy oil, are of primary interest these days. However, in-situ recovery processes of these resources are somewhat complicated, and there are many technical challenges accompanying it. For the recovery process, it is widely known that thermal techniques using steam are essential in reservoir heating. Especially, the steam-assisted gravity drainage process is a leading technology in the development of oil sands. This article presents the steam-assisted gravity drainage process for the production of oil sands by reviewing and analyzing several authors and companies. © 2012 Copyright Taylor and Francis Group, LLC.

Park Y.Y.,Ministry of Knowledge economics | Tran T.,Chonnam National University | Lee Y.H.,Chonnam National University | Nam Y.I.,Chonnam National University | And 2 more authors.
Hydrometallurgy | Year: 2010

Precipitation of Mg3(AsO4)2 for the removal of arsenic (As) from a molybdenum oxide processing plant liquor containing 70.9 g/L Mo(VI) and 469 mg/L As(V) was performed. The Stabcal software was used to model the speciation and solubility equilibria, and to identify the pH conditions at which optimum precipitation can be carried out. The optimum pH range for As(V) removal is between pH 7.5 and 10.2. This avoids the need to adjust the liquor pH to affect the precipitation. By adding magnesium chloride or sulphate at a Mg:As molar ratio of at least 2:1, As(V) could be removed to less than 5 mg/L at pH 10.2 resulting in a pure Mo(VI) liquor from which a high purity product of 99.9% MoO3 could be produced by acidification. © 2010 Elsevier B.V. All rights reserved.

Oh S.,University of Texas at San Antonio | Han M.-H.,Kyungil University | Im W.-B.,Ministry of Knowledge economics | Kim S.Y.,Yeungnam University | And 3 more authors.
Journal of Sol-Gel Science and Technology | Year: 2010

Coatings of biomedical implant surfaces by a bioactive calcium phosphate film render bioactivity to the implant surface and shorten the healing time. In this present study, calcium metaphosphate (CMP) sol was synthesized by sol-gel method and coated onto the titanium alloys (Ti-6Al-4V). CMP sol was first synthesized by reacting Ca(NO3)24H2O (Sigma-Aldrich 99%, USA) with (OC2H5)3P (Fluka 97%, Japan) in methyl alcohol. A stoichiometric Ca/P ratio of 0.5 was obtained by varying the amounts of the reactants. Sol was then coated on Ti-6Al-4V substrates by spin coating. The coated-specimens were then dried at 70 °C for 24 h, followed by a heat treatment at 650 °C for 1 h. Structural and chemical properties of the coatings were evaluated using XRD, SEM, and EPMA. The dissolution property of the coated-CMP layer was investigated by immersing the samples in the simulated body fluid (SBF) for 1, 3, 7 and 21 days. The concentration of Ca2+ released was measured using ICP. After heat treatment, SEM indicated a smooth and uniform CMP layer, with CMP grains of approximately 100 nm. The CMP phase was identified with δ-CMP (JCPDS #9-363). After immersion in SBF, coatings were observed to be roughened and porous. The concentration of Ca2+ in SBF was observed to increase over time, indicating continuous dissolution. The presence of titanium oxide phosphate compounds were also observed on CMP surfaces after immersion. It was thus concluded that the ability to control coating properties as well as the need for low heat treatment temperature offers advance for the use of CMP coating by sol-gel process on Ti-6Al-4V implant surfaces. © 2010 Springer Science+Business Media, LLC.

Din I.,Incheon National University | Kim J.,Ministry of Knowledge economics | Kim H.,Incheon National University
Journal of Applied Research and Technology | Year: 2013

This paper considers an energy-efficient utilization in lighting control systems (LCS). A joint power and beam angle control in LCS is proposed that reduces energy consumption while satisfying the user's lighting requirements. A problem to find the optimal pair of power and the beam angle of luminaries is formulated and an algorithm to find the optimal solution is suggested. The simulation results show that the proposed scheme achieves considerable improvement in energy savings compared to conventional lighting energy saving scheme which does not consider the beam angle control.

Chung T.,Sejong University | Bae W.,Sejong University | Nguyen N.T.B.,Sejong University | Dang C.T.Q.,University of Calgary | And 2 more authors.
Energy Sources, Part A: Recovery, Utilization and Environmental Effects | Year: 2011

Waterflooding has been practiced for several decades as a means of secondary recovery. This process is successful if there is uniform resistance to the injected water. However, due to its nature of heterogeneity, the injected water flows to the less resistant path, resulting in poor sweep efficiency. As one of many candidates to overcome this problem, polymer systems mixing with several types of chemical agents have been researched and applied for several years. In this article, the authors reviewed and summarized the Relative Permeability Modification/Disproportionate Permeability Reduction and water shutoff treatments. © 2012 Copyright Taylor and Francis Group, LLC.

Kim D.-S.,Korea Electronics Technology Institute | Kim B.-S.,Inha University | Won K.-H.,Korea Electronics Technology Institute | Kang M.-S.,Ministry of Knowledge economics
IEEE Transactions on Consumer Electronics | Year: 2010

Network enabled digital technology increases the connectivity of consumer devices within the home for the purpose of remote control and monitoring of network enabled devices. Such dynamic control scheme for multiple legacy IR controllable digital consumer electronics appliances increases power consumption and system complexity. In this paper, we present a wireless sensor node SoC with a profiled power management unit for reducing active power consumption of a battery operated interactive home remote controller. The profiled power management unit decides the behavior of the power management service and the classes of operating hardware blocks which is used to control power state and hardware reset management for a wireless sensor node SoC. A profile includes the consumer devices classes, activity property values, and methods for changing a pending power state and an immediate power state. Proposed wireless sensor node SoC consists of an 8- bit embedded microcontroller with 64 Kbytes in-system programmable flash memory, hardwired media access control (MAC), RF transceiver and digital baseband. We fabricate a wireless sensor node SoC using 0.18 um CMOS technology and organize a wireless sensor network for home automation. These results show that it reduces active power consumption about 18% and it can be successfully applied in wireless sensor networks for further interactive home automation system. © 2006 IEEE.

Kim M.J.,Ministry of Knowledge economics | Hergeth H.H.,North Carolina State University
Journal of the Textile Institute | Year: 2012

The paper describes the creation of an industry technology roadmap (ITR) for flushable, premoistened nonwoven wipes. It shows how technology roadmaps can be a tool for knowledge creation at the firm and at the industry level, and what adaptations have to be made for this particular industry. The ITR shows a market-driven strategic plan for the industry that includes market, infrastructure, technology, and regulation aspects that need to be addressed to assure growth and sustainability in the flushable, premoistened nonwoven wipes industry. © 2012 Copyright The Textile Institute.

Yang S.B.,Korea Advanced Institute of Science and Technology | Kong B.-S.,KCC Central Research Institute | Jung D.-H.,Ministry of Knowledge economics | Baek Y.-K.,Korea Advanced Institute of Science and Technology | And 3 more authors.
Nanoscale | Year: 2011

The use of carbon nanotubes (CNTs) as transparent conducting films is one of the most promising aspects of CNT-based applications due to their high electrical conductivity, transparency, and flexibility. However, despite many efforts in this field, the conductivity of carbon nanotube network films at high transmittance is still not sufficient to replace the present electrodes, indium tin oxide (ITO), due to the contact resistances and semi-conducting nanotubes of the nanotube network films. Many studies have attempted to overcome such problems by the chemical doping and hybridization of conducting guest components by various methods, including acid treatment, deposition of metal nanoparticles, and the creation of a composite of conducting polymers. This review focuses on recent advances in surface-modified carbon nanotube networks for transparent conducting film applications. Fabrication methods will be described, and the stability of carbon nanotube network films prepared by various methods will be demonstrated. © 2011 The Royal Society of Chemistry.

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