• Corrosion Science and Technology
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• v.3 no.5
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• pp.198-208
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• 2004

Although there has been no general agreement on the mechanism of primary water stress corrosion cracking (PWSCC) as one of major degradation modes of Ni-base alloys in pressurized water reactors (PWR's), common postulation derived from previous studies is that the damage to the alloy substrate can be related to mass transport characteristics and/or repair properties of overlaid oxide film. Recently, it was shown that the oxide film structure and PWSCC initiation time as well as crack growth rate were systematically varied as a function of dissolved hydrogen concentration in high temperature water, supporting the postulation. In order to understand how the oxide film composition can vary with water chemistry, this study was conducted to characterize oxide films on Alloy 600 by an in-situ Raman spectroscopy. Based on both experimental and thermodynamic prediction results, Ni/NiO thermodynamic equilibrium condition was defined as a function of electrochemical potential and temperature. The results agree well with Attanasio et al.'s data by contact electrical resistance measurements. The anomalously high PWSCC growth rate consistently observed in the vicinity of Ni/NiO equilibrium is then attributed to weak thermodynamic stability of NiO. Redox-induced phase transition between Ni metal and NiO may undermine the integrity of NiO and enhance presumably the percolation of oxidizing environment through the oxide film, especially along grain boundaries. The redox-induced grain boundary oxide degradation mechanism has been postulated and will be tested by using the in-situ Raman facility.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.2
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• pp.87-93
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• 2014

Cadastral parcel objects as polygons are fundamental dataset which represent land administration and management of the real world. Thus it is necessary to assure topological seamlessness of cadastral datasets which means no overlaps or gaps between adjacent parcels. However, the problem of overlaps or gaps are frequently found due to non-coinciding edges between adjacent parcels. These erroneous edges are called uncertain edges, and polygons containing at least one uncertain edge are called uncertain polygons. In this paper, we proposed a new algorithm to efficiently search parcels of uncertain polygons between two adjacent cadastral datasets. The algorithm first selects points and polylines around adjacent datasets. Then the Constrained Delaunay Triangulation (CDT) is applied to extract triangles. These triangles are tagged by the number of the original cadastral datasets which intersected with the triangles. If the tagging value is zero, the area of triangles mean gaps, meanwhile, the value is two, the area means overlaps. Merging these triangles with the same tagging values according to adjacency analysis, uncertain edges and uncertain polygons could be found. We have performed experimental application of this automated derivation of partitioned boundary from a real land-cadastral dataset.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.10 s.89
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• pp.977-982
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• 2004

In this paper, a dispersive anisotropic perfectly matched layer(APML) is proposed using piecewise linear recursive convolution(PLRC) for finite difference time domain(FDTD) methods. This proposed APML can be utilized for the analysis of a nonlinear dispersive medium as absorbing boundary condition(ABC). The formulation is simple modification to the original AMPL and can be easily implemented. Also it has some advantages of the PLRC approach-fast speed, low memory cost, and easy formulation of multiple pole susceptibility. We applied this APML to 2-D propagation problems in dispersive media such as Debye and Lorentz media The results showed good absorption at boundaries.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.531-534
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• 2011

It can be said that film and game industries take core parts of the comtemporary cultural industry. For consumers in modern industry, cultural industry is immensely significant as much as other industries. Because consumers are spending proportionally more money on experiential and emotional needs and less on basics such as food, housing, and clothes. Cultural industry is the one that can give us 'cultural satisfaction'. Some may say the film industry is different from the game industry in genre. However, we have no difficulty in finding many common characteristics between them since we are living in the world where any content or genre cannot stand alone and contents' boundaries diversify themselves to meet consumers' demand in daily basis. The purpose of this study is to look into the impact of the film industry on the game industry and to show how these different industries can coexist successfully by creating a synergy effect.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.1
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• pp.72-84
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• 2008

Since enactment of the Baekdu-Mountain Range protection law in Dec. 31st 2003, great interest arose in recovery of the natural environment in the Baekdu-Mountain Range. Since the Baekdu-Mountain Range has formed boundaries between different regions and it is the mountain that crosses our country from East to West, there are so many roads that penetrate this area. Slopes made by the construction of roads have poor foundation for the growth of vegetation and it takes a long period to restore only with natural restoration force. For this reason, various methods of revegetation to restore the damages are implemented but until now, revegetation of domestic soil cutting slopes are mainly covered by foreign import grasses to stabilize and cover grounds early. As we depended upon foreign import grasses for slopes revegetation, the landscape did not match in harmony with surrounding vegetation and therefore, we could see that these foreign grasses are withered in 2~3 years after the revegetation works and slopes become barren again. However, currently, there are no applicable standards for designs of green hill, desirable revegetation methods for the hill areas, roads and recovery models. Therefore, in this study, we investigated the status of revegetation plants and revegetation methods for the hill areas of the Baekdu-Mountain Range (azimuth, degree of tilt, and tilted places). Based on this, we attempted to find the desirable recovery models for the hill areas of the Baekdu-Mountain Range.

• The Transactions of the Korea Information Processing Society
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• v.6 no.12
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• pp.3530-3538
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• 1999

In this paper, we propose a novel method for feature extraction of off-line handwritten characters recognition based on human optical neural field model. The proposed feature extraction system divide into three parts ; 1) smoothing process, 2) removing boundaries(boundary lines), 3) extracting feature information. The proposed system first removes rough pixels which are easy to occur in handwritten characters. The system then extracts and removes the boundary information which have no influence on characters recognition. Finally, the feature information for off-line handwritten characters recognition is extracted. With PE2 Hangul database, we perform feature extraction experiments for off-line handwritten characters recognition. In the experiment results, the proposed system based on optical neural field shows that can extract the feature information of off-line handwritten characters including curve lines, circles, quadrangles and so on.

• Journal of the Korean Geographical Society
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• v.38 no.6
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• pp.906-921
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• 2003

This paper discusses the price effects of local growth controls on the housing markets of California jurisdictions in the late 1980s empirically. Particularly, based on spatial econometric modeling, the study focuses on the homebuilding constrained by growth controls which is one of the price effects. The modeling produces the California-wide generalizable results, differentiates among the individual effects of various growth controls on homebuilding, and covers spatial effects. Thereby, this study intends to supplement the existing work on the price effects of growth controls. The modeling results find that restrictive residential zoning had the effect of significantly restricting housing construction in the late 1980s. On the other hand, urban growth boundaries had the effect of accommodating homebuilding. Population growth or housing permit caps and adequate public facility ordinances had no significant effects on housing construction.

• Journal of Soil and Groundwater Environment
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• v.19 no.2
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• pp.25-37
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• 2014

The volcanic type of geothermal water is linked intimately to active or potentially active volcanoes and takes place near the plate boundaries. In contrast to the volcanic type, the geothermal water in Korea has a non-volcanic origin. Korea's geothermal water is classified into the residual magma (RM) type and deep groundwater (DG) type according to the criterion of $35^{\circ}C$. This study reviewed the relationship between the physical and chemical features of the 281 geothermal water sources in South Korea in terms of the specific capacity, water temperature, and chemical compositions of two different basements (igneous rock and metamorphic rock) as well as the geological structures. According to the spatial relationship between the geothermal holes and geological faults, the length of the major fault is considered a key parameter determining the movement to a deeper place and the temperature of geothermal water. A negligible relationship between the specific capacity (Q/s) and temperature was found for both the RM type and DG type with the greater specific capacities of the RM- and DG-igneous types than the RM- and DG-metamorphic types. No relationship was observed between Q/s and the chemical constituents ($K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$, $Zn^{2+}$, $Cl^-$, $SO_4{^{2-}}$, $HCO_3{^-}$, and $SiO_2$) in the DG-igneous and DG-metamorphic types. Furthermore, weak relationship between temperature and chemical constituents was found for both the RM type and DG type.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.146.2-146.2
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• 2013

Copper is considered to be the most promising substrate for the growth of high-quality and large area graphene by chemical vapor deposition (CVD), in particular, on the (111) facet. Because the interactions between graphene and Cu substrates influence the orientation, quality, and properties of the synthesized graphene, we studied the interactions using angle-resolved photoemission spectroscopy. The evolution of both the Shockley surface state of the Cu(111) and the ${\pi}$ band of the graphene was measured from the initial stage of CVD growth to the formation of a monolayer. Graphene growth was initiated along the Cu(111) lattice, where the Dirac band crossed the Fermi energy (EF) at the K point without hybridization with the d-band of Cu. Then two rotated domains were additionally grown as the area covered with graphene became wider. The Dirac energy was about -0.4 eV and the energy of the Shockley surface state of Cu(111) shifted toward the EF by ~0.15 eV upon graphene formation. These results indicate weak interactions between graphene and Cu, and the electron transfer is limited to that between the Shockley surface state of Cu(111) and the ${\pi}$ band of graphene. This weak interaction and slight lattice mismatch between graphene and Cu resulted in the growth of rotated graphene domains ($9.6^{\circ}$ and $8.4^{\circ}$), which showed no significant differences in the Dirac band with respect to different orientations. These rotated graphene domains resulted in grain boundaries which would hinder a large-sized single monolayer growth on Cu substrates.

• Korean Journal of Materials Research
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• v.19 no.1
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• pp.37-43
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• 2009

Silicon dioxide as gate dielectrics was grown at $400^{\circ}C$ on a polycrystalline Si substrate by inductively coupled plasma oxidation using a mixture of $O_2$ and $N_2O$ to improve the performance of polycrystalline Si thin film transistors. In conventional high-temperature $N_2O$ annealing, nitrogen can be supplied to the $Si/SiO_2$ interface because a NO molecule can diffuse through the oxide. However, it was found that nitrogen cannot be supplied to the Si/$SiO_2$ interface by plasma oxidation as the $N_2O$ molecule is broken in the plasma and because a dense Si-N bond is formed at the $SiO_2$ surface, preventing further diffusion of nitrogen into the oxide. Nitrogen was added to the $Si/SiO_2$ interface by the plasma oxidation of mixtures of $O_2/N_2O$ gas, leading to an enhancement of the field effect mobility of polycrystalline Si TFTs due to the reduction in the number of trap densities at the interface and at the Si grain boundaries due to nitrogen passivation.