• Korean Journal of Remote Sensing
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• v.34 no.5
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• pp.787-799
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• 2018

Accurate and effective mapping is critical step to monitor the spatial distribution and change of flood inundated area in large scale flood event. In this study, we try to suggest methods to use low spatial resolution satellite optical imagery for flood mapping, which has high temporal resolution to cover wide geographical area several times per a day. We selected the Sebou watershed flood in Morocco that was occurred in early 2010, in which several hundred $km^2$ area of the Gharb lowland plain was inundated. MODIS daily surface reflectance product was used to detect the flooded area. The study area showed several distinct spectral patterns within the flooded area, which included pure turbid water and turbid water with vegetation. The flooded area was extracted by thresholding on selected band reflectance and water-related spectral indices. Accuracy of these flooding detection methods were assessed by the reference map obtained from Landsat-5 TM image and qualitative interpretation of the flood map derived. Over 90% of accuracies were obtained for three methods except for the NDWI threshold. Two spectral bands of SWIR and red were essential to detect the flooded area and the simple thresholding on these bands was effective to detect the flooded area. NIR band did not play important role to detect the flooded area while it was useful to separate the water-vegetation mixed flooded classes from the purely water surface.

• Journal of the Korean GEO-environmental Society
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• v.10 no.6
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• pp.5-18
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• 2009

In construction of buildings in Korea, the buildings are frequently founded on the weathered ground (weathered soil/rock, fractured rock). In this case, to make a full use of a bearing capacity of a weathered ground for economic design, the shallow mat foundation system could be used. In this study, we have researched three cases of mat foundations on the weathered ground in Korea, and analyzed and considered the design procedures and the reinforcing methods. That is, we have considered the detail design, analysis proceedings, the ground settlement evaluation proceedings, the rock face mapping evaluations after excavation and reinforcing methods of the mat foundation on the weathered ground. And large scale plate load tests on the weathered ground supporting the mat foundation were performed and also load bearing capacity and settlement of actual mat foundation, considering the scale effect, were evaluated.

• Tunnel and Underground Space
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• v.32 no.6
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• pp.549-557
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• 2022

Tunnel face mapping involves the determination of rock discontinuities or weak rock conditions where extra support might be required. In this study, we investigated the application of Lidar scanning and photogrammetry to quantitatively characterize discontinuities of the rock mass on the tunnel face during excavation. The 3D models of tunnel faces generated by using these methods enable accurate and automatic discontinuity measurement to overcome the limitations of manual mapping. The results of this study show that both photogrammetry and Lidar can be used to reconstruct the 3D model of the tunnel face, although the photogrammetric 3D model is less detailed than its counterpart produced by Lidar. Given acceptable accuracy and cost-effectiveness, photogrammetry can be a fast, reliable, and low-cost alternative to Lidar for acquiring 3D models and determining rock discontinuities on tunnel faces.

• Journal of the Korean Graphic Arts Communication Society
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• v.15 no.2
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• pp.91-106
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• 1997

The new algorithm for halftone generation for gravure engraving was developed. The basic concept of this algorithm is based on the mapping and equal density expansion methods that we are mapped out. The program was used by the Microsoft Visiul C++2.0 and could be loaded in IBM personal computer.

• Communications of the Korean Mathematical Society
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• v.25 no.2
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• pp.207-214
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• 2010

In this paper, a generalized variational inequality problem is considered. An iterative method is studied for approximating a solution of the generalized variational inequality problem. Strong convergence theorem are established in a real Hilbert space.

• The Korean Journal of Nuclear Medicine
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• v.32 no.3
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• pp.225-237
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• 1998

Purpose: We investigated the statistical methods to compose the functional brain map of human working memory and the principal factors that have an effect on the methods for localization. Materials and Methods: Repeated PET scans with successive four tasks, which consist of one control and three different activation tasks, were performed on six right-handed normal volunteers for 2 minutes after bolus injections of 925 MBq $H_2^{15}O$ at the intervals of 30 minutes. Image data were analyzed using SPM96 (Statistical Parametric Mapping) implemented with Matlab (Mathworks Inc., U.S.A.). Images from the same subject were spatially registered and were normalized using linear and nonlinear transformation methods. Significant difference between control and each activation state was estimated at every voxel based on the general linear model. Differences of global counts were removed using analysis of covariance (ANCOVA) with global activity as covariate. Using the mean and variance for each condition which was adjusted using ANCOVA, t-statistics was performed on every voxel To interpret the results more easily, t-values were transformed to the standard Gaussian distribution (Z-score). Results: All the subjects carried out the activation and control tests successfully. Average rate of correct answers was 95%. The numbers of activated blobs were 4 for verbal memory I, 9 for verbal memory II, 9 for visual memory, and 6 for conjunctive activation of these three tasks. The verbal working memory activates predominantly left-sided structures, and the visual memory activates the right hemisphere. Conclusion: We conclude that rCBF PET imaging and statistical parametric mapping method were useful in the localization of the brain regions for verbal and visual working memory.

• Journal of Information Technology Services
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• v.5 no.2
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• pp.137-153
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• 2006

SOA(Service Oriented Architecture) can be a technique to make compassable software from mapping business service to software component. To support effective SOA, it is important that services have to be defined or classified more independently for dynamic and reusable composition. Several methods have been issued but no ways to defined service granularities, service type or service unit. In this paper we introduce 3 level views, service level, service granularity to reuse effectively. And, we suggest service definition guidelines using them.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.523-528
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• 1990

This paper discusses the problem of designing an observation function as coarsest as possible in supervisory control of discrete event dynamic systems. Some algebraic properties of two sets consisting of observation functions for which the given desirable behavior is realizable are investigated:these sets with a partial ordering turn out not to possess largest elements. Two natural methods of obtaining an observation function, which is frequently coarser than the identity mapping, are also presented. An example illustrates the use of these methods.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.1899-1902
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• 2003

Recently several methods have been developed for the virtual space construction. Generally, most of the methods are geometric-based rendering technic, but they are difficult to construct real-time rendering because of large data. In this paper, we present a three dimension image-based rendering method that enable a constant speed of real-time rendering regardless of object complexity in virtual space. The Proposed method shows good performance for the virtual space construction with high complexity.

• The Pure and Applied Mathematics
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• v.16 no.1
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• pp.85-98
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• 2009

Strong convergence theorems on viscosity approximation methods for finite nonexpansive mappings are established in Banach spaces. The main theorem generalize the corresponding result of Kim and Xu [10] to the viscosity approximation method for finite nonexpansive mappings in a reflexive Banach space having a uniformly Gateaux differentiable norm. Our results also improve the corresponding results of [7, 8, 19, 20].