• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.3
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• pp.152-163
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• 2020

The present study introduces a procedure to prepare and manage a high-resolution rainfall and soil moisture (SM) database in the LAMP prediction system, especially for landslide researchers. The procedure also includes converting the data into spatial resolution suitable for their interest regions following proper map projection methods. The LAMP model precipitation and SM data are quantitatively and qualitatively evaluated to identify the model prediction characteristics using the ERA5 reanalysis precipitation and observed 10m depth SM data. A detailed process of converting LAMP Weather Research and Forecasting (WRF) output data for 10m horizontal resolution is described in a step-wise manner, providing technical convenience for users to easily convert NetCDF data from the WRF model into TIF data in ArcGIS. The converted data can be viewed and downloaded via the LAMP website (http://df.ncam.kr/lamp/index.do) of the National Center for AgroMeteorology. The constructed database will contribute to monitoring and prediction of landslide risk prior to landslide response steps and should be data quality controlled by more observation data.

• The Journal of Engineering Geology
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• v.4 no.2
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• pp.187-206
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• 1994

Through a computer model study, optimum system configuration and field parameters were determined for high-resolution marine reflection surveys. Characteristics of far-field signatures were analysed in both time and frequency domains for the six individual R/V Onnuri. The analysis shows that the cluster fired at the depth of 2m below the sea surface generates the most ideal far-field signatures among the above seismic sources. Compared with the 96-channel streamer on the R/V Onnuri, the 12-channel streamer is suitable for shallow reflection profiling due to its high resolution both in the vertical and horizontal directions despite its lower signal-to-noise ratio. Considering factors including target depth, frequency range, airgun volume, number of recording channels, and capacity of compressors, optimum values for record length, sample period, and shot interval are believed to be is, 1ms, and 3.125m or 6.25m, respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6D
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• pp.1019-1023
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• 2006

The slope information based on DEM is very useful for urban planning, landscape, road design and water resource areas such as rainfall-runoff and soil erosion estimation. The resolution of slope, which is from DEM, can be variously decided by an application fields and the kinds of modeling method. In particular, the more decreased resolution makes the more decreased slope value because of the increased horizontal distance. This study presents slope evaluation method by aggregation method based on discharge and Manning's velocity equation to advance the loss of slope information in according to the resolution, and then applied it to calculate topographic factors of soil erosion model. As a result, conventional method shows 34.8% errors but aggregation method shows 12.6% errors. This study selected up-, middle-, and downstream region in watershed and analyzed the capability of aggregation method in order to estimate the influence of topographic characteristics. As a result of estimation, aggregation method shows more advanced results than conventional method. Therefore, the slope evaluation method by aggregation method can improve efficiently the loss of slope information in according to the variation of resolution in water resource area such as rainfall-runoff model.

• Journal of applied mathematics & informatics
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• v.7 no.2
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• pp.629-640
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• 2000

this paper present an efficient line-drawing algorithm that reduces the amount of space required, Because of its efficiency , this line-drawing algorithm is faster than the Bresenham algorithm or the recursive bisection method. this efficiency was achieved through a new data structure; namely , the modified segment tree (MST). Using the modified segment tree and the distribution rule suggested in this paper, we dra lines without generating the recursive calls used in [3] and without creating the binary operation used in [4]. we also show that line accuracy improves in proportion to the display resolution . In practice, we can significantly improve the algorithm's performance with respect to time and space, This improvement offer an increase in speed, specially with lines at or near horizontal, diagonal. or vertical ; that is, this algorithm requires the time complexity of (n) and the space complexity O(2k+1), where n is the number of pixels and k is a level of the modified segment tree.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.3
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• pp.621-627
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• 2010

This paper proposes an efficient architecture of Inter layer up-sampling in decoder for SVC(scalable video coding). A register bank for horizontal and vertical up-sampling and interpolation units are designed, by introducing the proposed architecture, 41% memory bandwidth is reduced compared to JSVM. For real-time operation for HD 6 layer decoder having CIF, SD, HD resolution for CGS layer, the hardware is designed to operate at 127MHz. The gate count is about 3000.

• Wind and Structures
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• v.10 no.4
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• pp.315-346
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• 2007

A preceding companion article introduced the slot jet approach for large-scale quasi-steady modelling of a downburst outflow. This article extends the approach to model the time-dependent features of the outflow. A two-dimensional slot jet with an actuated gate produces a gust with a dominant roll vortex. Two designs for the gate mechanism are investigated. Hot-wire anemometry velocity histories and profiles are presented. As well, a three-dimensional, subcloud numerical model is used to approximate the downdraft microphysics, and to compute stationary and translating outflows at high resolution. The evolution of the horizontal and vertical velocity components is examined. Comparison of the present experimental and numerical results with field observations is encouraging.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1446-1449
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• 2005

The purpose of this study is the real-time shape measurement of three-dimensional object by using color coded information. The paper relates to non-contact optical measurements of surface profiles or displacements, because of optical measurement systems are advantageous over using mechanical sensing, their relatively high speed and non-destructive capabilities. Therefore is particularly useful for three dimensional sensing which requires high horizontal and vertical resolution of measurements over a wide range thereof. Each a red, blue, green by using a inherence colors of hue value are good point.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.817-825
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• 1998

A three-dimensional ecosystem model is applied to the Suyoung Bay, located at the southeastern part of Korea, to study of the material distribution in the time scale of several tens days. The model has included of the DIN(Dissolved Inorganic Nitrogen), DIP(Dissolved Inorganic Phosphate), phytoplankton, zooplankton and detritus, and also was coupled with the physical processes. The spatial distribution of chlorophyll-a and primary productivity in the model is determined by the physical and chemical-biological parameters. The horizontal distributions of the DIN, DIP and chlorophyll-a are decreased from the coast to the off-shore, though the nutrients show some more complicated pattern than the chlorophyll-a. The nutrient contents in the off-shore are low, and thus a relatively low productivity(chlorophyll-a) are presented. On the whole, the distribution of the results of model are smoother than the observed ones and some small scale variation in the observed data cannot be reproduced by the model due to the resolution limits of model. However, the basic pattern and the quantitavities has been reproduced by the model well.

• Atmosphere
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• v.21 no.4
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• pp.471-480
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• 2011

This study investigates the characteristics of surface wind in North Korea using mesoscale model WRF. Hourly wind fields were simulated for one year representing mean characteristics of an 11-years period from 1998 to 2008. The simulations were performed on a nested grid from 27 km to 1 km horizontal resolution. The simulated wind map at 10 m above ground level is verified with 27 surface observations. Statistical verification skill score indicates that wind speed tends to overestimate in surface layer. The average RMSE value of the simulated wind speed is around $2.8ms^{-1}$. Wind map in North Korea showed that strong wind speed is distributed in the mountainous and western coastal region. The results of this wind mapping study contribute for the founding of wind energy potential location.

• The KSFM Journal of Fluid Machinery
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• v.10 no.4
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• pp.47-54
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• 2007

Simultaneous 3-D LDV measurements of the in-cylinder flows of three different engine setups were summarized for the quantification of the flow characteristics in each vertical or horizontal plane, and in entire cylinder volume. The ensemble averaged-velocity, tumble and swirl motions, and turbulent kinetic energy during the intake and compression strokes were examined from the measured velocity data (approximately 2,000 points for each engine setup). The better spatial resolution of the 3-D LDV allows measurements of the instantaneous flow structures, yielding more valuable information about the smaller flow structures and the cycle-to-cycle variation of these flow patterns. Tumble and swirl ratios, and turbulent kinetic energy were quantified as planar and volumetric quantities. The measurements and calculation results were animated for the visualization of the flow, and hence ease to analysis.