• The Transactions of the Korea Information Processing Society
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• v.4 no.9
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• pp.2403-2411
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• 1997

Direct3D is a recently developed 3D graphic accelerator such that we could make a Windows graphic programs with Direct3D easily. This paper presents the fractal terrain model viewer developed in terms of Direct3D. The object classes and the input dialog box used the model viewer, program initializing process, and the flow of the model viewer are discussed. Finally, the output of terrain formulation in wire-frame, solid, and point type form are presented. To show the results, the data of a terrain model were made by a fractal technique, the midpoint displacement methods with square lattices of points.

• Bulletin of the Korean Chemical Society
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• v.23 no.1
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• pp.35-40
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• 2002

Photoreaction of guest organic anions in layered organic-inorganic hybrid materials was investigated. The layered hybrids were synthesized by an anion-exchange reaction of $[LiAl_2(OH)_6]Cl{\cdot}yH_2O$ layered double hydroxide with aqueous (Z,Z)- and (E,E)-muconates under inert atmospheric condition, to give new organicinorganic hybrids of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$ and $[LiAl_2(OH)_6]_2[(E,E)-C_6H_4O_4]{\cdot}H_2O$, respectively. The basal spacings calculated by XRPD of intercalates indicate that muconate anions have almost vertical arrangements against the host $[LiAl_2(OH)_6]^+$ lattices in the interlayer of organic-inorganic hybrid materials. When UV light was irradiated on the suspension of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$, the (Z,Z)-muconate anions of the gallery space of hybrids were polymerized in the aqueous media while it was isomerized into more stable (E,E)-muconate in the methanollic suspension in the presence of catalytic amount of molecular iodine. All the products were characterized using elemental analysis, TGA, XRPD, FT-IR, $^1H$ NMR and $^{13}C$ CP-MAS NMR.

• Journal of the Korean Ceramic Society
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• v.53 no.4
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• pp.463-467
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• 2016

$Si^{4+}-N^{3-}$ was incorporated into $Ce^{3+}-doped$ lutetium aluminum garnet ($Lu_{2.965}Ce_{0.035}Al_5O_{12}$, $LuAG:Ce^{3+}$) lattices, resulting in the formation of $Lu_{2.965}Ce_{0.035}Al_{5-x}Si_xO_{12-x}N_x$ [(Lu,Ce)AG:xSN]. For x = 0-0.25, the synthesized powders consisted of the LuAG single phase, and the lattice constant decreased owing to the smaller $Si^{4+}$ ions. However, for x > 0.25, a small amount of unknown impurity phases was observed, and the lattice constant increased. Under 450 nm excitation, the PL spectrum of $LuAG:Ce^{3+}$ exhibited the green band, peaking at 505 nm. The incorporation of $Si^{4+}-N^{3-}$ into the $Al^{3+}-O^{2-}$ sites of $LuAG:Ce^{3+}$ led to a red-shift of the emission peak wavelength from 505 to 570 nm with increasing x. Corresponding CIE chromaticity coordinates varied from the green to yellow regions. These behaviors were discussed based on the modification of the $5d^1$ split levels and crystal field surroundings of $Ce^{3+}$, which arose from the Ce-(O,N)8 bonds.

• Carbon letters
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• v.26
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• pp.11-17
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• 2018

Milled carbon fiber (mCF) was prepared by a ball milling process, and X-ray diffraction (XRD) diffractograms were obtained by a $2{\theta}$ continuous scanning analysis to study mCF crystallinity as a function of milling time. The raw material for the mCF was polyacrylonitrile-based carbon fiber (T700). As the milling time increased, the mean particle size of the mCF consistently decreased, reaching $1.826{\mu}m$ at a milling time of 18 h. The XRD analysis showed that, as the milling time increased, the fraction of the crystalline carbon decreased, while the fraction of the amorphous carbon increased. The (002) peak became asymmetric before and after milling as the left side of the peak showed an increasingly gentle slope. For analysis, the asymmetric (002) peak was deconvoluted into two peaks, less-developed crystalline carbon (LDCC) and more-developed crystalline carbon. In both peaks, Lc decreased and $d_{002}$ increased, but no significant change was observed after 6 h of milling time. In addition, the fraction of LDCC increased. As the milling continued, the mCF became more amorphous, possibly due to damage to the crystal lattices by the milling.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.469-473
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• 2006

In general, a classification process between ground data and non-ground data, which include building objects, is required prior to producing a DEM for a certain surface reconstruction from LiDAR data in which the DEM can be produced from the ground data, and certain objects like buildings can be reconstructed using non-ground data. Thus, an exact classification between ground and non-ground data from LiDAR data is the most important factor in the ground reconstruction process using LiDAR data. In particular, building objects can be largely used as digital maps, orthophotos, and urban planning regarding the object in the ground and become an essential to providing three dimensional information for certain urban areas. In this study, an entropy theory, which has been used as a standard of disorder or uncertainty for data used in the information theory, is used to apply a more objective and generalized method in the recognition and segmentation of buildings from raw LiDAR data. In particular, a method that directly uses the raw LiDAR data, which is a type of point shape vector data, without any changes, to a type of normal lattices was proposed, and the existing algorithm that segments LiDAR data into ground and non-ground data as a binarization manner was improved. In addition, this study proposes a generalized building extraction method that excludes precedent information for buildings and topographies and subsidiary materials, which have different data sources.

• Macromolecular Research
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• v.12 no.2
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• pp.213-218
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• 2004

We have performed dispersion polymerization of acrylamide in tert-butyl alcohol/water mixture-using hydroxypropyl cellulose and ammonium persulfate as the stabilizer and the initiator, respectively - to study the effects that the concentration of monomer, initiator, and stabilizer, the tert-butyl alcohol/water ratios as polymerization media, and the reaction temperature have on, among other things, the polymerization kinetics, particle sizes, and molecular weights. The polymerization rate increased upon increasing the concentration of the monomer, initiator, and stabilizer, the water content in the tert-butyl alcohol/water media, and the polymerization temperature. The average particle size of the lattices increased upon increasing the concentration of initiator, the polymerization temperature, and the water content in the tert-butyl alcohol/water media, but it decreased upon increasing the concentration of monomer and stabilizer. The viscosity-average molecular weight increased upon increasing the concentration of monomer and stabilizer and the water content in the tert-butyl alcohol/water media, but it decreased upon increasing both the concentration of initiator and the polymerization temperature.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.33-38
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• 1997

Criticality experiments with fixed neutron poison plates for water moderated and reflected low enriched(2.35 and 4.31 wt%) UO$_2$fuel rod clusters were evaluated to validate calculation techniques employed in analyzing fuel shipping and storage systems having steel, boral, or cadmium shield. Measurements were obtained for both the 2.35 wt% and the 4.31 wt% enriched rods in square pitched, water flooded lattices. The critical experiments with the 2.35 wt% enriched rods consists of three 20$\chi$ 16 or 20$\chi$ 17 fuel cluster. Critical separation were used in the experiments with the 4.31 wt% enriched fuel rods. In the experiments, the poison plates were placed on both sides of the centrally located fuel cluster. Critical separation between the three sub-critical fuel clusters were then measured for varying plate thicknesses and distances of the plates to the center fuel cluster. Calculations were performed for thirty eight critical configuration using KENO-V. a and MCNP. All of the results were within 1.23% in $\Delta$k when individually compared with the critical value of 1.0. Discrepancies of the code results are probably due to uncertainties in experiments and/or analytical modeling experiments. In general, MCNP predictions were observed to be in best agreement with the experiments.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.1
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• pp.414-430
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• 2016

Verifier-local revocation (VLR) seems to be the most flexible revocation approaches for any group signature scheme, because it just only requires the verifiers to possess some up-to-date revocation information, but not the signers. Langlois et al. (PKC 2014) proposed the first VLR group signature based on lattice assumptions in the random oracle model. Their scheme has at least Õ(n²) ⋅ log N bit group public key and Õ(n) ⋅ log N bit signature, respectively. Here, n is the security parameter and N is the maximum number of group members. In this paper, we present a simpler lattice-based VLR group signature, which is more efficient by a O(log N) factor in both the group public key and the signature size. The security of our VLR group signature can be reduced to the hardness of learning with errors (LWE) and small integer solution (SIS) in the random oracle model.

• Journal of Adhesion and Interface
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• v.7 no.3
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• pp.10-15
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• 2006

After anchoring 3-(2-aminoethylamino)propyltriethoxysilane (APTES) onto the surfaces of the channels within ordered mesoporous silica, SBA-15, we dispersed $Cu^{2+}$-perfluorophthalocyanine into the modified SBA-15 channels. From small-angle X-ray scattering (SAXS) patterns and transmission electron microscopy (TEM) images, we confirmed that both the calcined and $Cu^{2+}$-perfluorophthalocyanine-incorporated SBA-15 samples possessed ordered periodic structures and hexagonal symmetry lattices (p6mm). The value of the $d_{100}$ spacing was decreased after the incorporation of $Cu^{2+}$-perfluorophthalocyanine into the modified SBA-15 channels. We used FTIR and UV-Vis spectroscopy and thermogravimetric analysis (TGA) to characterize both the modified SBA-15 and the $Cu^{2+}$-perfluorophthalocyanine-incorporated SBA-15 samples. From scanning electron microscopy (SEM) images and $N_2$ sorption measurements, we found that the $Cu^{2+}$-perfluorophthalocyanine units were incorporated within the modified SBA-15 channels, rather than on the external surfaces of the modified SBA-15 channels.

• Journal of the Korean Solar Energy Society
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• v.25 no.3
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• pp.19-25
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• 2005

Francis turbine of commercial small hydropower plants under 10kw which is investigate a flow characterist and an efficiency in the research which it sees, the problem and an improvement is investigate. In the research which it is simply model with casing, guide-vane, runner, draft tube for simulation numerical analysis of small-sized Francis turbine. Model uses the Gambit and it composes with approximately 800,000 non-uniform lattices. Solutions are investigate the hydraulic characteristics against an outward angle of guide vane, the number of guide vane, head(inlet velocity) by using FLUENT which is a commercial business code.