• Title/Summary/Keyword: Decomposition mechanism

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Cointegrated Relations between Foreign Ownership and Business Conditions in the Level of Korean Capital Market

  • Kim, Ju-Wan
    • The Korean Journal of Financial Management
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    • v.26 no.1
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    • pp.127-163
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    • 2009
  • This paper examines the results of survey that the foreign ownership is cointegrated with capital market conditions in Korea using Vector Error Correction Model (VECM) and how the mechanism of innovations and dynamics among the foreign ownership and capital market proxies in the VECM was described. Specifically, we find that the foreign ownership and capital market proxies follow I (1) process and there are cointegrated relations between the foreign ownership and capital market proxies. Adopting the impulse response function and variance decomposition in the VECM, we suggest, in turn, the default risk premia, liquidity of market and the rate of interest in long term business cycle take on a special function on the KSE and KOSDAQ. Finally, we also offer evidences of which there are differences of the mechanism of dynamics and innovations between on the KSE and on the KOSDAQ.

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Structural parameter estimation combining domain decomposition techniques with immune algorithm

  • Rao, A. Rama Mohan;Lakshmi, K.
    • Smart Structures and Systems
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    • v.8 no.4
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    • pp.343-365
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    • 2011
  • Structural system identification (SSI) is an inverse problem of difficult solution. Currently, difficulties lie in the development of algorithms which can cater to large size problems. In this paper, a parameter estimation technique based on evolutionary strategy is presented to overcome some of the difficulties encountered in using the traditional system identification methods in terms of convergence. In this paper, a non-traditional form of system identification technique employing evolutionary algorithms is proposed. In order to improve the convergence characteristics, it is proposed to employ immune algorithms which are proved to be built with superior diversification mechanism than the conventional evolutionary algorithms and are being used for several practical complex optimisation problems. In order to reduce the number of design variables, domain decomposition methods are used, where the identification process of the entire structure is carried out in multiple stages rather than in single step. The domain decomposition based methods also help in limiting the number of sensors to be employed during dynamic testing of the structure to be identified, as the process of system identification is carried out in multiple stages. A fifteen storey framed structure, truss bridge and 40 m tall microwave tower are considered as a numerical examples to demonstrate the effectiveness of the domain decomposition based structural system identification technique using immune algorithm.

Photocatalytic Degradation Mechanism of Methyl Mercaptan using $TiO_2$ (TiO$_2$를 이용한 메틸메르캅탄의 광촉매 분해메커니즘)

  • Lee, Byung-Dae;Lee, Jin-Shik;Kim, Yeoung-Chan
    • Journal of the Korean Applied Science and Technology
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    • v.24 no.3
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    • pp.296-300
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    • 2007
  • This paper presents applicability of photocatalytic decomposition of methyl mercaptan using $TiO_2$. A quartz reactor was used in order to elucidate reaction pathway in photocatalytic decomposition of methyl mercaptan. Experimental results showed that more than 99.9% of methyl mercaptan was decomposed within 30 minutes. It was found that the photocatalytic decomposition of methyl mercaptan followed pseudo first order and its reaction coefficient was $0.05min^{-1}$ During 30 minutes in the photocatalytic reaction, the concentration of methyl mercaptan, dimethyl disulfide, $SO_2$, $H_2SO_4$, COS, $H_2S$ were determined. These results showed that 64% of methyl mercaptan were compensated for the increase in sulfur after 30 minutes through the mineralization. The proposed main photocatalytic decomposition pathway of methyl mercaptan was methyl $mercaptan{\rightarrow}dimethyl$ $disulfide{\rightarrow}SO_2{\rightarrow}H_2SO_4$.

Characteristics of TPH Decomposition in a Close-typed Simulated Biopile System Amended with a Sintered Porous Media (소결다공체를 적용한 Closed Type 모사바이오파일시스템의 TPH 분해 특성)

  • Jung, Hyun-Gyu;Choi, Sang-Il;Kim, Hye-Jin;Kim, Sang-Kook;Kim, Yu-Beom
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.3
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    • pp.415-424
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    • 2011
  • This research was conducted to verified the effectiveness of a sintered porous media coated with organic matter as nutrient source and microorganisms as decomposer effective in TPH decomposition for a closed-typed biopole system. The organic matter content in the sintered porous media which was developed with bentonite increased with increasing dilution ratio of pig slurry and the sintered porous media as well as decrease in the particle size of sintered porous media. The decomposition rate of TPH was significantly increased with increasing aeration than that under atmospheric condition. Also the sintered porous media containing organic matter and microorganisms proved that the decomposition was enhanced with addition of nutrients sources in addition to aeration periodically.

Kinetics and Mechanism of Reaction of Hydrogen Peroxide with Copper(Ⅱ)-Schiff Base Complexes (구리(Ⅱ)-시프염기 착물과 과산화수소의 반응속도 및 메카니즘)

  • Kim, Sun-Deuk;Joung, Mu-Su;Jin, Gyoung-Rok;Kim, Chang-Su
    • Journal of the Korean Chemical Society
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    • v.39 no.12
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    • pp.932-939
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    • 1995
  • Rates of the decomposition of hydrogen peroxide by copper(Ⅱ)-Schiff base complexes were measured at various concentrations of hydrogen peroxide. Decomposition rates of hydrogen peroxide increased with increasing pH for CuⅡBSDT and CuⅡBSTP but then decreased with the same variation of the pH for CuⅡBSTT. A possible mechanism in accord with experimental results was proposed. The mechanism involves the deprotonation of copper(Ⅱ)-Schiff base complexes of hydrogen peroxide, followed by the formation of peroxo complexes at the rate-determining step.

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Decomposition of Toxic Chemicals in Microemulsion by Electrolytic Oxidation Method (마이크로 에멀젼 상태에서 전기분해법을 이용한 독성물질 분해 연구)

  • Shim, Sung-Hyun;Chun, Byoung-Chul;Chung, Yong-Chan
    • Clean Technology
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    • v.14 no.3
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    • pp.218-223
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    • 2008
  • Decomposition of reactive organic compound dispersed in microemulsion media by hydroxide ions and proton ions generated during electrolysis was tried and the half-lifes for decomposition were compared. Absorbance of p-nitrophenoxide produced from the decomposition of p-nitrophenylacetate (PNPA) was followed to find the rate of decomposition. The applied voltage, temperature, and the amount of substrate were changed to see the effects on the decomposition rate. The advantages of electrolysis in microemulsion system were the high solubilizing capacity of substrate, easy control of decomposition rate, low operation cost, no need for any addition of chemicals, and no byproducts. The mechanism of decomposition and the application to water purification were discussed.

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Quantum Chemical Calculation of NO Decomposition over Cu-Y Zeolite (Cu-Y 제올라이트상의 NO분해반응에 대한 양자화학적 해석)

  • Kim, Myung-Chul
    • Applied Chemistry for Engineering
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    • v.7 no.2
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    • pp.321-325
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    • 1996
  • Quantum chemical calculations are used to characterize the decomposition of nitrogenmonoxide over $Cu^{n+}$-Y zeolite. The method of theoretical calculations, such as CNDO/2, have been applied to cluster models representing cation sites in zeolite to obtain total energies, LUMO energies, and Wiberg bond orders. The calculated total energies and bond orders of cluster models showed the reaction mechanism of NO decomposition over $Cu^{n+}$ site in zeolite framework. The suggested cluster models of varying Si/Al ratios studied with exchange cations in the $Cu^+$ and in the $Cu^{2+}$ states. And the calculated LUMO energies can predict L acidifies of cluster models. The results from these experiments showed the possibility of the mechanism of NO decomposition, progressing adsorption of NO, conversion to $N_2$ and $O_2$, desorption of $N_2$ and $O_2$ in sequence. The L acidity of $Cu^{2+}$ ion in cation site is more strong than $Cu^+$.

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A Deep Investigation of the Thermal Decomposition Process of Supported Silver Catalysts

  • Jiang, Jun;Xu, Tianhao;Li, Yaping;Lei, Xiaodong;Zhang, Hui;Evans, D.G.;Sun, Xiaoming;Duan, Xue
    • Bulletin of the Korean Chemical Society
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    • v.35 no.6
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    • pp.1832-1836
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    • 2014
  • A deep understanding of the metallic silver catalysts formation process on oxide support and the formation mechanism is of great scientific and practical meaning for exploring better catalyst preparing procedures. Herein the thermal decomposition process of supported silver catalyst with silver oxalate as the silver precursor in the presence of ethylenediamine and ethanolamine is carefully investigated by employing a variety of characterization techniques including thermal analysis, in situ diffuse reflectance infrared Fourier transform spectroscopy, scanning electron microscopy, and X-ray diffraction. The formation mechanism of supported silver particles was revealed. Results showed that formation of metallic silver begins at about $100^{\circ}C$ and activation process is essentially complete below $145^{\circ}C$. Formation of silver was accompanied by decomposition of oxalate group and removal of organic amines. Catalytic performance tests using the epoxidation of ethylene as a probe reaction showed that rapid activation (for 5 minutes) at a relatively low temperature ($170^{\circ}C$) afforded materials with optimum catalytic performance, since higher activation temperatures and/or longer activation times resulted in sintering of the silver particles.

Relationship between Concentration of Phosphorus, Turbidity, and pH in Water and Soil under Aerobic and Anaerobic Conditions (혐기와 호기 상태의 물과 토양에서 pH, PO4-P, 탁도, T-P 농도 관계)

  • Min, Young-Hong;Kang, Sam-Woo;Lee, Hoi-Seon;Chung, Nam-Hyun
    • Journal of Applied Biological Chemistry
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    • v.54 no.3
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    • pp.225-229
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    • 2011
  • This research was carried out to elucidate the impacts of dissolved oxygen (DO) concentration to phosphorus release mechanism from soil into water in lakes. $PO_4-P$ contributed to the growth of the total phosphorus (T-P). $PO_4-P$ was steadily increasing because water was accumulating $PO_4-P$. T-P was closely related to turbidity, pH, and DO. We found that DO had decreased because DO was consumed in organic matter decomposition, and that the resulting anaerobic decomposition occurred whenever water had run out of DO. We also found that pH had decreased sharply by production of organic acid by the anaerobic decomposition and that T-P decreased because a decrease in pH removed turbidity by precipitation. T-P was dissolved without microbial decomposition. This mechanism was of great importance in lakes because phosphorus is released from soil into water.