• 제목/요약/키워드: Energy dependency

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Foreign Direct Investments of Economic Infrastructure-Related Public Companies in Korea(2): Typologies, Characteristics of FDI and Interpretation of Nationality Issues (경제 하부구조 관련 공기업의 해외투자에 대한 연구(2) - 해외 하부구조투자의 유형과 성격, 국적성의 문제 -)

  • Kim, Yong-Chang
    • Journal of the Economic Geographical Society of Korea
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    • v.15 no.2
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    • pp.166-191
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    • 2012
  • This paper investigates how the agent specificity of economic infrastructure-related public company proceeds in overseas investments. At first this paper examines general features focused on investment region, project type, starting year, and then analyzes overseas investments based on specific cases with three classifications which are composed of special consulting type that do not accompany capital investment, FDI type, and type of overseas energy resources development that go with capital investment and business risk. Finally nationality issues that is generated by agent characteristics of infrastructure public company are interpreted in perspective of duality which is financial pressure and dependency of host county's position, and relationship with private capital of home country.

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Thermal Kinetics of Color Changes of Purple Sweet Potato Anthocyanin Pigment (자색고구마 Anthocyanin 색소의 가열에 대한 속도론적 연구)

  • Lee, Lan-Sook;Rhim, Jong-Whan
    • Korean Journal of Food Science and Technology
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    • v.29 no.3
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    • pp.497-501
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    • 1997
  • Kinetic parameters on heat-induced color changes of anthocyanin pigment from purple sweet potato were determined in the temperature range of $121{\sim}141^{\circ}C$. Color change determined by a browning index $(A_{532}\;nm/A_{420}\;nm)$ followed second order reaction kinetics. Activation energy values of purple sweet potato pigment solutions of pH 2.0, 3.0, 4.0 and 5.0 were 69.57, 76.68, 81.07 and 92.98 kJ/mol, respectively, indicating that temperature dependency of the reaction increased with pH. Apparent kinetic compensation effect between preex-ponential factor and activation energy value was observed.

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Study on Electrical Properties and Structures of ZTO Thin Films Depending on the Annealing Temperature (ZTO 박막의 열처리온도에 따른 결정성과 전기적인 특성 연구)

  • Jo, Yun Jung;Chae, Hong Ju;Oh, Teresa
    • Industry Promotion Research
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    • v.1 no.2
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    • pp.13-17
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    • 2016
  • ZTO films were annealed in a vaccum atmosphere conditions to research the temperature dependency of current-voltage characteristics. The ZTO film annealed in a vacuum became an amorphous structure but films annealed in an atmosphere condition had a crystal structure. The defects or depletion layer were formed by the electron-hole combination after annealing processes, and the electrical properties were changed depending on the crystal structure, binding energy and the variation of carriers. ZTO became more crystal-structural with increasing the annealing temperature, and the current increased at ZTO film annealed at $150^{\circ}C$ with Schottky contact.

Characteristics of Nylon6/Ionomer Semi IPN for Molded-In-Color Compound (나일론6/이오노머 Semi IPN의 몰드-인-칼라 수지 특성 연구)

  • Lee, Ja-Hun;Hwang, Jin-Taek;Kang, Ho-Jong
    • Polymer(Korea)
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    • v.36 no.4
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    • pp.407-412
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    • 2012
  • The characteristics of nylon6/ionomer semi interpenetrating networks (IPN) as a molded-in-color (MIC) compound had been studied, and comparison was made with nylon6/ionomer blends. Nylon6/ionomer semi IPN shows better homogeneity in phase morphology than nylon6/ionomer blend, and it caused better anti-scratching performance than the blend. This semi IPN structure resulted in lowered crystallization rate, increased melt viscosity and less temperature dependency of viscosity. As a result, we may expect the enhancement of melt processing characteristics in an injection molding process using nylon6/ionomer semi IPN as a MIC compound.

Up-conversion Luminescence Characterization of CeO2:Ho3+/Yb3+ Particles Prepared by Spray Pyrolysis

  • Jung, Kyeong Youl;Min, Byeong Ho;Kim, Dae Sung;Choi, Byung-Ki
    • Current Optics and Photonics
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    • v.3 no.3
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    • pp.248-255
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    • 2019
  • Spherical $CeO_2:Ho^{3+}/Yb^{3+}$ particles were synthesized using spray pyrolysis, and the upconversion (UC) properties were investigated with changing the preparation conditions and the infrared pumping power. The resulting particles had a size of about $1{\mu}m$ and hollow structure. The prepared $CeO_2:Ho^{3+}/Yb^{3+}$ particles exhibited intense green emission due to the $^5F_4/^5S_2{\rightarrow}^5I_8$ transition of $Ho^{3+}$ and showed weak red or near-IR peaks. In terms of achieving the highest UC emission, the optimal concentrations of $Ho^{3+}$ and $Yb^{3+}$ were 0.3% and 2.0%, respectively. The UC emission intensity of prepared $CeO_2:Ho^{3+}/Yb^{3+}$ particles had a linear relationship with crystallite size and concentration quenching was caused by dipole-dipole interaction between the same ions. Based on the dependency of UC emission on the pumping power, the observed green upconversion was achieved through a typical two-photon process and concluded that the main energy transfer from $Yb^{3+}$ to $Ho^{3+}$ was involved in the ground-state adsorption (GSA) process.

Thickness dependency of MAHONOS ($Metal/Al_2O_3/HfO_2/SiO_2/Si_3N_4/SiO_2/Si$) charge trap flash memory

  • O, Se-Man;Yu, Hui-Uk;Kim, Min-Su;Lee, Yeong-Hui;Jeong, Hong-Bae;Jo, Won-Ju
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.34-34
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    • 2009
  • The electrical characteristics of tunnel barrier engineered charge trap flash (TBE-CTF) memory with $SiO_2/Si_3N_4/SiO_2/Si$ engineered tunnel barrier, $HfO_2$ charge trap layer and $Al_2O_3$ blocking oxide layer (MAHONOS) were investigated. The energy bad diagram was designed by using the quantum-mechanical tunnel model (QM) and then the CTF memory devices were fabricated. As a result, the best thickness combination of MAHONOS is confirmed. Moreover, not enhanced P/E speed (Program: about $10^6$ times) (Erase: about $10^4$ times) but also enhanced retention and endurance characteristics are represented.

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Fuel Cell as an Alternative Distributed Generation Source under Deregulated Power System (규제가 없는 전력계통에서 대체분산형전원으로서의 연료전지)

  • Lee, Kwang-Y.;Kim, Se-Ho;Kim, Eel-Whan;Kim, Ho-Chan
    • Proceedings of the KIEE Conference
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    • 2006.07a
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    • pp.331-332
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    • 2006
  • This paper proposes the fuel cell power plants as alternative energy sources for distributed generation in Jeju Island, Korea. This will help to increase the fuel efficiency, at least double the current thermal power plants, decrease environmental pollution, virtually to none, increase the reliability of power supply, reducing the dependency of the HVDC link, and provide quality power to the growing infrastructure in meeting the requirements for the free-trade international island.

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Rheological Properties of Biopolymer Produced by Pseudomonas delafieldii (Pseudomonas delafieldii가 생성하는 다당류의 레올로지 특성)

  • Yoo, Jin-Young;Chung, Dong-Hyo
    • Microbiology and Biotechnology Letters
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    • v.17 no.5
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    • pp.475-480
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    • 1989
  • The extracellular polysaccharide was isolated from the culture of Ps. delafieldii and its rheological property was evaluated. The aqueous solution was extremely viscous and shows pseudoplastic behaviour. The flow behaviour index and apparent viscosity of 1 %solution were 0.09 and 1169 mPa·s. The solution was stable over pH change but did not have thermal stability. The activation energy of flow of 1 % solution was 4.44 kcal/mole. The concentration dependency could be expressed double logarithmically.

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COMPARATIVE STUDIES ON MANUAL,ANIMAL DRAWN,TWO WHEEL TRACTOR AND FOUR WHEEL TRACTOR OPERATED TILLAGE OPERATION IN SWAZILAND

  • Nath, Surya
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.1013-1025
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    • 1993
  • Agriculture in Swaziland is the most important sector of the economy from the stand point of export earning, rural employment and dependency for family food. But, inspite of 65.5 percent of the household being busy in food production for family consumption in Swaziland, the import bill of food and live animals is rising from E119.7268 million in 1987/90 (An.St.Bul.1988) . A typical farm size, based on holding's growing crops, is only 1.93 ha which may prohibit owning a four wheel tractor for farm operations. The traditional hand tools are just not efficient and comfortable to operate in order to exploit full potential of the land. There are over 120.000 draught animals which have potential to be utilized in farming. The two wheel-tractor is another energy source which can be used for many farm-operations.

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Dislocation dynamics simulation on stability of high dense dislocation structure interacting with coarsening defects

  • Yamada, M.;Hasebe, T.;Tomita, Y.;Onizawa, T.
    • Interaction and multiscale mechanics
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    • v.1 no.4
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    • pp.437-448
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    • 2008
  • This paper examined the stability of high-dense dislocation substructures (HDDSs) associated with martensite laths in High Cr steels supposed to be used for FBR, based on a series of dislocation dynamics (DD) simulations. The DD simulations considered interactions of dislocations with impurity atoms and precipitates which substantially stabilize the structure. For simulating the dissociation processes, a point defect model is developed and implemented into a discrete DD code. Wall structure composed of high dense dislocations with and without small precipitates were artificially constructed in a simulation cell, and the stability/instability conditions of the walls were systematically investigated in the light of experimentally observed coarsening behavior of the precipitates, i.e., stress dependency of the coarsening rate and the effect of external stress. The effect of stress-dependent coarsening of the precipitates together with application of external stress on the subsequent behavior of initially stabilized dislocation structures was examined.