• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.497-500
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• 2005

Research and development of remote sensing technique is necessary so that more accurate and extensive information may be obtained. To achieve this goal, the synthesized technique which integrates the high resolution optic and SAR image, and topographical information was examined to investigate the quantitative/qualitative characteristics of the Earth's surface environment. For this purpose, high-precision DEMs of Jeju-Island was generated and data fusion algorithm was developed in order to integrate the multi-spectral optic and polarimetric SAR image. Three dimensional land-cover and two dimensional soil moisture maps were generated conclusively so as to investigate the Earth's surface environments and extract the geophysical parameters.

• ALGAE
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• v.20 no.4
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• pp.369-377
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• 2005

Seashore joining with land and sea, which is typical habitat for marine macroalgae, is classified two types of shore as soft- and hard-bottom shore according to topographical (geological) and ecological features. We compared two of Ulva pertusa Kjellman from two contrasting habitats, sandy (soft-bottom, Haenam) and rocky shore (hard-bottom, Hadong) in terms of chlorophyll-a fluorescence and its parameters, and various photosynthetic pigment and nutrient content in the tissue of those. Both of habitats were different in the light environment such as light attenuation coefficient and even in nutrient concentration of ambient seawater. Electron transport rate (ETR) of Ulva from sandy shore was higher than from rocky shore. The range of photosynthetic pigment content in the tissue of U. pertusa was significantly much more in from sandy shore, and also nitrogen and phosphorus content were significantly higher except for carbon content. However, there were no significant differences in the ratio of among photosynthetic pigments, and N:P ratio was similar between each other, even though significantly different. Our result implied on the reason of why most of green tides in the worldwide concentrated and frequently occurred at sites with sandy, muddy and silty bottoms, being classified as soft-bottom shore.

• Journal of the Korean Society of Safety
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• v.31 no.1
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• pp.105-110
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• 2016

Mountainous disasters such as landslides and debris flow are difficult to forecast. Debris flow in particular often flows along the valley until it reaches the road or residential area, causing casualties and huge damages. In this study, the researchers selected Seoraksan National Park area located at Inje County (Inje-gun), Gangwon Province-where many mountainous disasters occur due to localized torrential downpours-for the damage reduction and cause analysis of the area experiencing frequent mountainous disasters every year. Then, the researchers conducted the field study and constructed geospatial information data by GIS method to analyze the characteristics of the disaster-occurring area. Also, to extract more precise geographic parameters, the researchers scanned debris flow triggering area through terrestrial LiDAR and constructed 3D geographical data. LiDAR geographical data was then compared with the existing numerical map to evaluate its precision and made the comparative analysis with the geographic data before and after the disaster occurrence. In the future, it will be utilized as basic data for risk analysis of mountainous disaster or disaster reduction measures through a fine-grid topographical map.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.269-275
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• 1997

Car Navigation System with Global Positioning System (GPS) can display position direction and the shortest cut of one's destination. The position datum for GPS in World Geodetic System 1984 (WGS-84) coordinates system need to transform Bessel coordinates system and process Map projection. Since 1987, GPS has used the WGS-84. WGS-84 is a geocentric equipotential ellipsoid of revolution which is defined four parameters. In this study, by comparing the digitized topographical map with the digital map of GPS datum we can consider the technique of WGS84 digital map.

• Korean Journal of Metals and Materials
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• v.50 no.10
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• pp.763-768
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• 2012

The uniform and highly smooth nanofibers of biocompatible poly(${\varepsilon}$-caprolactone) (PCL) composited with different contents of multiwalled carbon nanotubes (MWCNTs) were successfully prepared by electrospinning. Experimental parameters were MWCNTs addition to a PCL solution and applied voltages. The topographical features of the composite nanofibers were characterized by scanning electron microscopy and its electrical properties were measured by a four-point probe method. The surface resistance gradually decreased with an increasing content of MWCNTs in PCL fibers because of the excellent electrical conductivity of MWCNTs. The nanofiber diameter could be regulated by varying the solution viscosity and voltages. Our results establish that this kind of electrospinning PCL/MWCNTs nanofibers with the control of fiber diameter and electrical conductivity may be a promising candidate for the application of scaffolds in tissue engineering.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.157-164
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• 1997

This study deals with GPS-photogrammetry practicability by C/A-code reception. It allows data to be acquired and analyzed fast. Combined block adjustment method was applied at the topographical map production of coast-land. And we compared it that of conventional block adjustment. As a result, it was found that accuracy was very sensitive to the arrangement and number of control points. The accuracy in the horizontal and vertical was $\pm{2cm}$ if all of the control points was available. however accuracy was not affected at additional parameters for systematic errors' elimination and it leads to bad results when the number of control points was few and arrangement of control points was not stabilized. GPS observations were added in block adjustment, but the accuracy of block was not upgraded due to the low accuracy of C/A-code reception. So relative positioning method with carrier phases was required for high accuracy and it is expected that CPS photogrammetry with C/A-code will be used widely according to the improvement of observation methods and the development of receiver.

• Journal of Korea Water Resources Association
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• v.37 no.8
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• pp.631-641
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• 2004

The objective of this study is to test the applicability of SLURP (Semi-distributed Land Use-based Runoff Process) on Soyanggang-dam watershed. SLURP model is a conceptual semi-distributed form model that can be used to examine irrigation plan and the effects of proposed changes in water management within a basin or to see what effects external factors such as climate change or changing land cover might have on various water users. Topographical parameters were derived from DEM using TOPAZ and SLURPAZ. Monthly NDVIs were calculated from multi-temporal NOAA/AVHRR images during four years (1998 ∼ 2001). Weather elements (dew-point temperature, solar radiation, maximum/minimum temperature and relative humidify) were obtained from five meteorological stations within and near the study area. To simulate daily hydrograph during 1998 ∼ 2001, the model parameters of each land cover class were optimized by sensitivity analysis and SCE-UA method. Test result of SLURP was summarized by various statistics method (WMO volume error, Nash-Sutcliffe efficiency, mean error and coefficient of variation).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6D
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• pp.771-779
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• 2009

Digital topographical maps used for GIS DB are mainly produced by the traditional way of analogue aerial photogrammetry. Therefore, analogue photos are only available for digital mapping after preprocessing such as film developing, printing and scanning. However, digital aerial camera is able to get digital image directly without preprocessing and thus the performance and efficiency of photogrammetry are extremely increased. This study aims to investigate geometric stability of digital aerial frame camera DMC (Digital Modular Camera). In order to verify the geometric stability of digital aerial camera DMC, some different block conditions with and without cross strips, GPS/INS data and variation of GCPs are introduced in the block adjustment. The accuracy results of every block condition were compared each other by computation of residuals of exterior orientation (EO) parameters. Results of study shows that the geometric stability of the block adjustment with cross strips is increased about 30% against without cross strips. The accuracy of EO parameters of block adjustment with cross strips is also increased about 2cm for X-coordinate, 3cm for Y-coordinate, 3cm for Z-coordinate, and 6" for omega, 4" for phi and 3" for kappa.

• Journal of the Korean Association of Geographic Information Studies
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• v.5 no.4
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• pp.9-23
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• 2002

The purpose of this research was to develop a model that minimizes time and money for deriving topographical property factors and hydro-meteorological property factors, which are used in interpreting flood flow, and that makes it possible to forecast rainfall-runoff using a least number of factors. That is, the research aimed at suggesting a runoff interpretation method that considers the river branching characteristics but not the topographical and geological properties and the land cover conditions, which had been referred in general. The subject basin of the research was the basin of Yeongcheon Dam located in the upper reaches of the Kumho River. The parameters of the model were derived from the results of abstracting topological properties out of rainfall-runoff observation data about heavy rains and Digital Elevation Modeling(DEM). According to the result of examining calculated peak runoff, the Clark Model and the GIUH Model showed relative errors of 1.9~23.9% and 0.8~11.3%, respectively and as a whole, the peak values of hydrograph appeared high. In addition, according to the result of examining the time when peak runoff took place, the relative errors of the Clark Model and the GIUH Model were 0.5~1 and 0~1 hour respectively, and as a whole, peak flood time calculated by the GIUH Model appeared later than that calculated by the traditional Clark Model.

• Journal of Korean Society of Forest Science
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• v.94 no.1 s.158
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• pp.26-33
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• 2005

The study was carried out to provide information about growth and ecological characteristics by site types of natural deciduous forest in Pyeongchang, Gangwon Province. The data were collected from four aspects(the East, the West, the South, and the North) with three elevation(higher than 1.000 m, 700~1,000 m, lower than 700 m) and three topographical conditions(ridge, hill, and valley). Growth parameters by site types were evaluated based on the growth performances of dbh for the last 5 to 10 years; which were also estimated based on both Pressler and Schneider formulae. In addition, ecological characteristics such as Shannon-Wiener's diversity index, evenness index and richness index were analyzed by site types. The management methods by site types were suggested by considering stand density, growth patterns, and ecological characteristics. It was found that the stands on the South and the East are necessary the tending practices to improve growth and ecological characteristics. On the other hand, the West and the North needed the tending practices focusing on stand density management to increase growth rate rather than ecological management. It was also found that the area lower than 700 m in elevation showed Higher growth rate than other areas. As a management standard considered in terms of growth rate, it was suggested that tending practices should be applied to the stands of which growth rate for the last 5 to 10 years were lower than 2%. Considering topographical conditions, valley area showed better ecological characteristics than both ridge and hilly areas. Consequently, it was revealed that the valley areas were suitable for the ecological management.