• Archives of Pharmacal Research
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• v.16 no.2
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• pp.118-122
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• 1993

The effects of n-alkanols on the rotational relaxation time of 1, 6-dipheny-1, 3, 5-hexatriene (DPH) in synaptosomal plasma membrane vesicles isolate from fresh bovine cerbral contex were investigated. n-Alknols decreased the rotational relaxation time of 1, 6-diphenyl-1, 3, 5-hexatriene in the native membranes and the potencies of n-alkanols up to 1-nonanol increased by 1 order of magnitude as the carbon chain length increases by two carbon atoms, The cut-off phenomenon was reached at 1-decanol, where further increase in hydocabon length resulted in an increase in the rotational relaxation time of DPH in the native membranes.

• Korean Journal of Metals and Materials
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• v.47 no.11
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• pp.773-785
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• 2009

Studies of a number of Cu-Zr amorphous alloys have demonstrated that those exhibiting greater plastic strain during homogeneous deformation at room temperature show lower global plasticity associated with inhomogeneous deformation in a typical compression test. Using a combination of experiments and molecular dynamics simulations, we clarify this seeming paradox between the homogeneous and inhomogeneous deformation by exploring the microstructural aspects in view of the structural disordering, disorder-induced softening, and shear localization and relate these findings to the global plasticity of bulk amorphous alloys. Additional analyses were conducted to derive a simple structural parameter that allows the prediction of the global plasticity of bulk amorphous alloys.

• Korean Journal of Metals and Materials
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• v.46 no.11
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• pp.701-707
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• 2008

This study examined the creation mechanism of free volume during homogeneous deformation induced by the elastostatic compression at room temperature. Experiments demonstrated that amorphous alloys subjected to the elastostatic compression underwent structural disordering, during which densely packed polyhedra breakdown to form new, loosely packed ones, resulting in the creation of excess free volume. A combination of experiments and molecular dynamics simulations are used to explore fundamental issues on how free volume is created during elastostatic compression.

• Annual Conference of KIPS
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• 2009.04a
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• pp.1206-1209
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• 2009

모바일 단말의 이동성을 지원하는 호스트 기반의 MIPv6, HMIPv6 및 FMIPv6 프로토콜이 개발되었지만, 이동성 기능을 단말기에 구현해야 하는 부담이 있다. 이러한 문제점을 해결하기 위해 최근에 네트워크 기반으로 동작하는 PMIPv6 프로토콜이 등장하였다. 그러나 라우팅 최적화나 핸드오버 지연시간을 단축해야 하는 과제가 아직 남아 있다. 따라서, 본 논문에서는 사용자의 인증절차를 간소화하여 지연시간을 줄이고, 핸드오버 시간 동안 패킷들을 LMA 의 별도 광 버퍼링 공간에 저장하였다가 재전송함으로써 패킷 disordering 문제점을 해결하는 기법을 제안한다. 성능평가는 분석 모델을 통해 평가하며, 제안기법의 핸드오버 지연시간은 표준 PMIPv6 대비 33% 개선된 성능을 보인다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.20 no.1
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• pp.18-25
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• 2017

Damage of both life and property has been increased by natural disaster under the influence of climate change, thus many natural disaster vulnerability researches have been carried out to make adaptation policy and impact assessment of climate change recently. Their method for assessing vulnerability usually have used proxy variables for making vulnerability indices. However, because their results were too qualitative and relative it tends to be hard to make absolute comparison and establish standard of prevention or adaptation ability. Accordingly, this study aimed at quantifying natural disaster vulnerability using emergy through recognizing disaster as the relations between order and disorder by system approach. As a result, ordering energy (4.66E+22 sej/yr) and ordered structure (1.98E+22 sej) of Busan in 2003 and disordering energy (7.80E+18 sej), disordered parts (4.55E+20 sej) and rebuilding energy (3.87E+20 sej) by typhoon Maemi were analysed. And then, this was compared with Hurricane Andrew in Dade County. Through this comparison, if the prevention ability of Busan increases, disordered parts can be reduced against the more powerful disordering energy. Also, prevention for additional damages by disaster is needed to practical rebuilding action. In conclusion, it was able to figure out the impact of disaster quantitatively by natural systems and urban systems showing as common measure. Based on this study and further research to make effective prevention for how much prevention ability should be increased will contribute to producing the scientific data for disaster management policy in future.

• Journal of the Korean Ceramic Society
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• v.42 no.4
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• pp.292-297
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• 2005

$LiMO_{2}(M=Co,Ni)$ samples were synthesized with $Li_{2}CO_{3},\;Co_{3}O_{4}$, and NiO by the solid-state reaction method. In the case of $LiCoO_{2}$, at low temperature$(T=400^{\circ}C)$ spinel structure was synthesized and the obtained spinel phase was transformed to layered phase at high temperature$(T\ge600^{\circ}C)$. The phase transition behaviors of $LiCoO_{2}$ were investigated with various heating temperature and time. The rate of transition was directly proportional to the concentrations of reactant, and activation energy of reaction was around 6.76 kcal/mol. When CoO(rock salt structure) was used as a starting material instead of $Co_{3}O_{4}$(spinel structure), layered structure of $LiCoO_{2}$ was obtained at low temperature. In the case of $LiNiO_{2}$ the transition from layered structure to rock salt structure occurred easily by disordering/ordering reaction, but did not occur in $LiCoO_{2}$. The difference in metal ion radii in $LiCoO_{2}$ and $LiNiO_{2}$ results in different behaviors of phase transitions.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.222.2-222.2
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• 2015

A $Ge_2Sb_2Te_5$ nanowire (GST NW) phase change memory device is investigated with Joule heating electrodes. GST is the most promising phase change materials, thus has been studied for decades but atomic structure transition in the phase-change area of single crystalline phase-change material has not been clearly investigated. We fabricated a phase change memory (PCM) device consisting of GST NWs connected with WN electrodes. The GST NW has switching performance with the reset/set resistance ratio above $10^3$. We directly observed the changes in atomic structure between the ordered hexagonal close packed (HCP) structure and disordered amorphous phase of a reset-stop GST NW with cross-sectional STEM analysis. Amorphous areas are detected at the center of NW and side areas adjacent to heating electrodes. Direct imaging of phase change area verified the atomic structure transition from the migration and disordering of Ge and Sb atoms. Even with the repeated phase transitions, periodic arrangement of Te atoms is not significantly changed, thus acting as a template for recrystallization. This result provides a novel understanding on the phase-change mechanism in single crystalline phase-change materials.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.411-414
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• 2002

As high density of cities, construction project is getting to be high rise, large sized and multi purposed, whereas it has some difficulties due to disordering of classification and undeveloped management systems. In this study, it would be suggested that classification method for knowledge and constraint of temporary facility in order to efficient decision making of temporary facility planning with knowledge reorganization and establishment process.

• Progress in Superconductivity and Cryogenics
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• v.22 no.2
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• pp.21-25
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• 2020

We investigated the flux pinning property of GdBa₂Cu₃O_7-x (GdBCO) films on top of La_0.7Sr_0.3MnO₃ (LSMO) nanoparticles deposited by a surface decoration. Both GdBCO films and LSMO nano particles were deposited by pulsed laser deposition and the number of laser pulses were varied from 80 to 320 in order to control the density of the LSMO nanoparticles. The magnetization data at 77 K showed that the critical current density (J_c) was enhanced in all of the GdBCO films with LSMO nanoparticles and that the J_c enhancement was found to be inversely proportional to the LSMO nanoparticle density. Structural analyses revealed that LSMO nanoparticles induce a compressive strain in the GdBCO films resulting in a disordering in the CuO₂ plane. Therefore, the enhanced flux pinning property in the GdBCO with LSMO nanoparticles was attributed to the competing effect between the increase of pinning centers and the increase of compressive strain in the superconducting phase.

• Proceedings of the Korean Magnestics Society Conference
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• 2010.06a
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• pp.70-71
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• 2010

In this study, We fabricated FePt-based perpendicular patterned media using a selective combination of E-beam lithography and either Ar plasma etching (deposition-first process) or FePt lift-off (deposition-last process). We employed the deposition-last process to avoid chemical and structural disordering by impinging Ar ions (deposition-first process). For a patterned medium with 100 nm patterns made by this process, the out-of-plane coercivity was measured to be 5 fold larger than its in-plane value. The deposition-last process may be a promising way to achieve ultra-high density patterned media.