• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.71-74
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• 2002

It is necessary to increase VUV radiation for improve luminous efficiency of PDP . It is important to know wave-forms of VUV radiation and density of exited Xe atoms or 1S4 and 1S5 of the cells. We survey on their measurement methods.

• Journal of Magnetics
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• v.12 no.3
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• pp.93-96
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• 2007

We investigated the electronic structure and magnetic properties of zinc-blende CrP/SrBi interface by using the all-electron full-potential linearized augmented plane wave method within the generalized gradient approximation. It is found that the half-metallicity is destroyed when the two half-metals are in contact. Magnetic moments of the atoms forming the supercell differ considerably from the respective values obtained for the bulk structures of the two materials. Cr atoms being and not being in contact with Bi atoms have magnetic moment 3.43 and $2.69{\mu}_B$, respectively. Bi atoms lose their majority electrons which results in their negative polarization. Alkaline Sr atoms are very weakly negatively polarized. The spin distribution within the supercell is such that well separated regions of positive and negative polarization are seen, especially around the layer of P atoms being in contact with the layer of Sr atoms.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.185.2-185.2
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• 2014

We have studied the atomic and electronic structure of graphene nanoribbons (GNRs) on a hexagonal boron nitride (h-BN) sheet with intercalated atoms using first-principles calculations. The h-BN sheet is an insulator with the band gap about 6 eV and then it may a good candidate as a supporting dielectric substrate for graphene-based nanodevices. Especially, the h-BN sheet has the similar bond structure as graphene with a slightly longer lattice constant. For the computation, we use the Vienna ab initio simulation package (VASP). The generalized gradient approximation (GGA) in the form of the PBE-type parameterization is employed. The ions are described via the projector augmented wave potentials, and the cutoff energy for the plane-wave basis is set to 400 eV. To include weak van der Waals (vdW) interactions, we adopt the Grimme's DFT-D2 vdW correction based on a semi-empirical GGA-type theory. Our calculations reveal that the localized states appear at the zigzag edge of the GNR on the h-BN sheet due to the flat band of the zigzag edge at the Fermi level and the localized states rapidly decay into the bulk. The open-edged graphene with a large corrugation allows some space between graphene and h-BN sheet. Therefore, atoms or molecules can be intercalated between them. We have considered various types of atoms for intercalation. The atoms are initially placed at the edge of the GNR or inserted in between GNR and h-BN sheet to find the effect of intercalated atoms on the atomic and electronic structure of graphene. We find that the impurity atoms at the edge of GNR are more stable than in between GNR and h-BN sheet for all cases considered. The nickel atom has the lowest energy difference of ~0.2 eV, which means that it is relatively easy to intercalate the Ni atom in this structure. Finally, the magnetic properties of intercalated atoms between GNR and h-BN sheet are investigated.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1996.10b
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• pp.3-12
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• 1996

Cold fusion technologies now are being developed very successfully. The $\pi$-far infrared rays are generated from three dimensional crystallizing $\pi$-bondings of oxygen atoms in water molecules. The growing cavity in water molecules make near resonance state and a vortex of infrared rays and attracts $\pi$-far infrared rays in the water. The cavity surrounded by a lot of $\pi$-far infrared rays has a very strong gravitational field. The $\pi$-far infrared rays are contracted into $\pi$-far infrared rays of half wave length and of one wave length. The $\pi$-far infrared rays of half wave length generate heat while $\pi$-far infrared rays of one wave length are contracted into $\pi$-gamma rays of one wave length. The contracted $\pi$-gamma rays of one wave length make nucleons and mesons, which is the creation and transmutation of matter by covalent bondings and three-dimensional crystallizing $\pi$-bondings into implosion bonding. Patterson power cell generates a very strong gravitational cavity because the electrolysized oxygen atoms make $\pi$-far infrared rays than in plain water.

• Journal of the Korean Magnetics Society
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• v.22 no.5
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• pp.157-161
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• 2012

Magnetism at the interfaces of rocksalt structured half-metals, NaN and CaN were investigated by use of the first-principles band calculations. The electronic structures for the simple interface and mixed interface systems were calculated by the FLAPW (full-potential linearized augmented plane wave) method. From the calculated number of electrons in muffin-tin spheres of each atom, we found, for the simple interface system, that the magnetic moment of the N atom in the CaN (NaN) side is increased (decreased) compared to those of inner N atoms. For the mixed interface system, the magnetic moments of the interface N atoms are similar to the averaged value for the inner N atoms in CaN and NaN side. Among four interface N atoms, the N atom connected to Na atoms in the upper and down layers has the largest magnetic moment and that connected to Ca atoms has the smallest. The number of p electrons in each N atom and the calculated density of states explain well the above situation.

• Interaction and multiscale mechanics
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• v.1 no.4
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• pp.467-476
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• 2008

In this work, a nano-size rocksalt crystal (magnesium oxide) is considered as a continuous collection of unit cells, while each unit cell consists of discrete atoms; and modeled by a multiscale concurrent atomic/continuum field theory. The response of the crystal to an electromagnetic (EM) wave is studied. Finite element analysis is performed by solving the governing equations of the multiscale theory. Due to the applied EM field, the inhomogeneous motions of discrete atoms in the polarizable crystal give rise to the change of microstructure and the polarization wave. The relation between the natural frequency of this system and the driving frequency of the applied EM field is found and discussed.

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.65-66
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• 2008

• Journal of Magnetics
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• v.18 no.4
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• pp.375-379
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• 2013

The electronic and the magnetic properties of (001) surface of $KCaN_2$ half-metallic compound with full-Heusler structure are studied with the use of a full-potential linearized augmented plane wave method. Two possible terminations of the surface are considered and only the one with N atoms in the topmost layer is found to retain the half-metallic properties of the bulk. The magnetic properties of N-terminated surface are enhanced compared with the properties of the bulk. The calculated magnetic moments on the N atoms in the $KCaN_2$ are 1.26 ${\mu}_B$ in the bulk and 1.90 ${\mu}_B$ at the surface. The subsurface metal atoms are also slightly polarized. In the surface terminated with metal atoms, not only the half-metallicity is destroyed, but also the magnetic properties of the system are weakened.

• Journal of Information Processing Systems
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• v.16 no.1
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• pp.30-41
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• 2020

Lines and textures are natural properties of the surface of natural objects, and their images can be sparsely represented in suitable frames such as wavelets, curvelets and wave atoms. Based on characteristics that the curvelets framework is good at expressing the line feature and wavesat is good at representing texture features, we propose a model for the weighted sparsity constraints of the two frames. Furtherly, a multi-step iterative fast algorithm for solving the model is also proposed based on the split Bergman method. By introducing auxiliary variables and the Bergman distance, the original problem is transformed into an iterative solution of two simple sub-problems, which greatly reduces the computational complexity. Experiments using standard images show that the split-based Bergman iterative algorithm in hybrid domain defeats the traditional Wavelets framework or curvelets framework both in terms of timeliness and recovery accuracy, which demonstrates the validity of the model and algorithm in this paper.

• Bulletin of the Korean Chemical Society
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• v.11 no.2
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• pp.89-94
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• 1990

The redox properties of 2-amino-1-cyclopentene-1-dithiocarboxylate anion (acdc) and its oxovanadium complex, $VO(acdc)_2$ have been investigated in dimethylformamide (DMF) with polarography and cyclic voltammetry. Bis(2-amino-1-cyclopentene-1-dithiocarboxylate) oxovanadium(IV) exhibits two polarographic oxidation waves and two reduction waves in the potential range from +0.50V to - 2.4V vs. the Ag/AgCl (DMF) reference electrode. The second oxidation wave appeared at - 0.08V is found to be reversible and is attributed to the formation of $VO(acdc)_2\;^+$. The first reduction process (at - 0.60V) is also reversible and this reduction process is caused by the electrode process of formation of $VO(acdc)_2$-species. The half wave potential for the reduction, V(IV)$\to$V(III) is more positive for oxovanadium complexes containing sulfur donor atoms than other VO(IV) complexes having oxygen or nitrogen donor atoms.