• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.29-32
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• 2008

In this paper, we propose one unsupervised classification technique using the degree of polarization (DoP) and the co-polarized phase-difference (CPD) statistics, instead of the entropy and alpha. It is shown that the DoP is closely related to the entropy, and the CPD to the alpha. The DoP explains the feature how much the effect of multiple reflections is contained. Hence, the DoP could be used as an important factor for classifying classes. The CPD can also be computed from the measured Mueller matrix elements. For the smooth surface scattering, the CPD is about $0^{\circ}$, and for dihedral-type scattering, the CPD is about $180^{\circ}$. A DoP-CPD diagram with appropriate boundaries between six different classes is developed based on the SAR image. The classification results are compared with the existing Entropy-alpha diagram as well as the IPL-AirSAR polarimetric data. The technique may have capability to classify an SAR image into six major classes; a bare surface, a village, a crown-layer short vegetation canopy, a trunk-layer short vegetation canopy, a crown-layer forest, and a trunk-dominated forest. Based on the DoP and CPD analysis, a simple three-component decomposition technique was also proposed.

• Korean Journal of Optics and Photonics
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• v.18 no.6
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• pp.421-425
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• 2007

A new 3D rear projection display system using double-layer polarization-selective screen systems, one stacked in front of the other, has been developed. The front and rear screens are made of scattering polarizer films, and they either diffuse-scatter or transmit the incident light depending on the polarization state of the light. The near and for images are projected onto the front and rear screens, respectively, using light waves with mutually orthogonal polarization states. The new display system produces clear high-resolution images, which are visible over a wide range of viewing angle. It was found that the impression of depth is pronounced and eyestrain is only comparable to that by 2D display systems.

• The Journal of the Acoustical Society of Korea
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• v.25 no.7
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• pp.339-345
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• 2006

We suggest new 2D two-way Parabolic equation algorithm for multiple scattering. Our method is based on the successive performance of the single scattering approach. First. as the single scattering algorithm, the reflected and transmitted fields are calculated at the vertical interface of a range independent sector. Then. the reflected field is saved and the transmitted field Propagated to the next vertical interface with the split-step Pade method. After one step ends, the same Process is repeatedly performed with the change of the Propagation direction until the reflected field at the vertical interface is close to zero. Final incoming and outgoing fields are obtained as the sum of the wave fields obtained for each step. Our algorithm is relatively simple for the numerical implementation and requires less computational resources than the existing algorithm for multiple scattering

• Journal of Environmental Science International
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• v.12 no.5
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• pp.521-527
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• 2003

To study the intruded phenomena of North Pacific Ocean around Boso peninsular, water property distribution in the adjacent seas to Japan is studied using the hydrographic data obtained by Japan Maritime Agency and Japan Fisheries Agency from 1973 to 1996, The scattering of water type in T-5 diagram is relatively small in the Kuroshio Region. Both the envelopes of saline side and of fresh side of the scattered data points shifts gradually from saline side to fresh side as the observation Line moves from southwest to northeast. In mixed water region, the scattering of water type increases rapidly as the observation line moves north; the envelope of fresh cold side moves towards fresh cold side much faster than that of saline side. This suggests that the water does not advect along the salinity minimum layer, but the salinity minimum layer can be understood as a boundary of two different waters aligned vertically, We defined the typical water masses as the Oyashio Water and the Kuroshio Water. The water mass below the salinity minimum layer may be created by isopycnal mixing of these two water masses with a fixed mixing rate. While the water mass above the salinity minimum cannot be created simply by isopycnal mixing. The salinity minimum layer may be eroded from upper side due to active minxing processes in the surface layer, while the water of the salinity minimum layer moves gradually southward. This appears to give an explanation why the thermosteric anomaly value at salinity minimun decereases towards south.

• Journal of Magnetics
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• v.12 no.3
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• pp.118-123
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• 2007

We have studied the effect of Au-Cu back layer system ${\sim}10{\AA}$ thick on the properties of a spin valve. The back layers were Cu, Au, co-sputtered $Cu_xAu_{1-x}$, laminated $[Au/Cu]_n$. and bi-layer [Au/Cu]. When Au was added to the Cu, the resistance of the spin valve abruptly increased most likely due to impurity scattering. The GMR values were not increased significantly for all the structures. In the case of co-sputtered $Cu_xAu_{1-x}$, the changes in the resistance, ${\Delta}R$, was increased at a composition of ${\sim}Au_{0.5}Cu_{0.5}$. This increase in ${\Delta}R$ is due to increase in the resistance and not from the enhanced spin-dependent scattering. The structural analyses showed that the orthorhombic $Au_{0.5}Cu_{0.5}$ was formed in the back layer instead of the face-centered tetragonal $Au_{0.5}Cu_{0.5}$ as we expected. Thermal annealing over $400^{\circ}C$ may be required to have face-centered tetragonal in the $10{\AA}$ thick ultra-thin film. In the case of a laminated or bi-layered back layer, the properties of the spin valve were improved, which may be attributed to the increase in the mean free path of conduction electrons.

• Journal of the Korean Magnetics Society
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• v.8 no.5
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• pp.288-294
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• 1998

Effect of degree of intermixing at the Ta/NiFe interface induced by varying applied substrate bias voltage during NiFe free layer deposition on change of magnetoresistance in Substrate/Ta/NiFe/Cu/NiFe/FeMn/Ta spin valve multilayers was investigated. It was found that the optimum NiFe free layer thickness showing a maximum MR increase with increasing the bias voltage. The increase of the optimum thickness was due to the increase of the intermixed layer thickness with a bias voltage. The weak ferromagnetic or non ferromagnetic intermixed layer plays as a spin-independent scattering region and does not contribute on spin-dependent scattering. The existence of the intermixed layer was proved by the means of electrical resistivity and magnetization changes. In the present study, the optimum "effective" free layer thickness which gives the highest MR ratio was a constant independent of the magnitude of the bias voltage we have used.have used.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.784-786
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• 2004

Overlap errors and side-lobes can be simultaneously solved by the rule-based correction using scattering bars with the rules extracted from test patterns. Process parameters affecting the attPSM lithography simulation have been determined by the fitting method to the process data. Overlap errors have been solved applying the correction rules to the metal patterns overlapped with contact/via. Moreover, the optimal insertion rule of the scattering bars has made it possible to suppress the side-lobes and to get additional pattern fidelity at the same time.

• Proceedings of the Korea Crystallographic Association Conference
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• 2002.11a
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• pp.17-17
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• 2002

Time-of-flight impact collision ion scattering spectroscopy (TOF-ICISS) was applied to study the geometrical structure of the epitaxially grown BaTiO₃ layers on the MgO(100) surface. Hetero-epitaxial BaTiO₃ layers can be deposited by the following steps: first thermal evaporation of titanium onto the MgO(100) surface in the atmosphere of oxygen at 400℃, secondly thermal evaporation of barium in the same manner, and finally annealing at 800℃. Well ordered perovskite BaTiO₃ was confirmed from the ICISS spectra and reflection high electron energy diffraction (RHEED) patterns. It was also revealed that BaTiO₃ had cubic structure with the same lattice parameter of bulk phase.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3575-3580
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• 2011

This paper reports a methodology for preparing close-packed two dimensional gold nanoprism films and hexagonal nanoplate films at a hexane/water interface. By controlling the concentration of linker molecules in the hexane layer and the temperature of the colloid solution, highly ordered close-packed nanoplate arrays can be fabricated. These films were investigated to compare their corresponding surface enhanced Raman scattering (SERS) efficiencies. It was demonstrated that the Au nanoprism films resulted in a stronger SERS enhancement than the Au hexagonal nanoplate films. The difference in the SERS enhancement is attributed to the film array difference, demonstrating that Au nanoprism films have a higher line contact density than their Au hexagonal analogues.

• Proceedings of the KSRS Conference
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• v.2
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• pp.680-683
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• 2006

A one-dimensional planar model is considered of the atmosphere with multi-layer clouds illuminated by a mono-directional parallel flux of solar radiation. A new approach is proposed to radiation transfer modeling and daylight background formation for the atmosphere with such clouds that is represented as a heterogeneous multi-layer system each layer of which is described by different optical characteristics. The influence functions of each layer are determined by solutions of the radiation transfer boundary problem with an external monodirectional wide flux while the contribution of multiple scattering and absorption in the layer is taking into account.