• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.380-390
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• 1994

This study was conducted to investigate the effects of the topographical factors (16 items), physico-chemical properties of soil (13 items) and meteorological factors(9 items) on the height growth of Pinus thunbergii stands along the coastal area in Korea. According to the coefficients by partial correlation analysis in total area, it was found that tree height growth was considerably affected by local topography, soil hardness, soil B-horizental depth, effective soil depth, soil moisture, parent rock, soil texture, and etc.. And the soil factors were available $P_2O_5$, total nitrogen, base saturation, exchangeable $Ca^{{+}+}$, and etc.. In partial correlation analysis, annual relative humidity, annual precipitation, index of aridity, and etc. were found to be the most important factors influencing on tree height growth of Pinus thunbergii stands. In conlusion, the topographical, soil and meteorological factors have multiplex influence on the tree height growth in the Pinus thunbergii stands. They promise to provide the basis of improving not only the selection of suitable sites and the management of soil fertilizer but also the estimation of growth and yield. Hence these results would be used successfully for the design in the scientific forest working plan.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3D
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• pp.445-450
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• 2008

Recently, environmental and ecological approaches is in progress in urban stream, especially the guarantee of instream flow becomes very important. In this paper, it is suggested that water volume estimation method utilizing the topographical shape data obtained by field investigation and satellite image to manage the urban stream efficiently. The data obtained at Gap River is the study area are analysed and those results are as belows. First, surveying to investigate topographic shape characteristics of urban stream is carried out. In details, the gradient characteristics from water surface to bottom in case of sand area and in case of grass area are 0.013 and 0.065 respectively. In conclusion, the gradient characteristic of grass area is five times bigger than that of sand area. Besides, IKONOS image is classified by spectrum analysis and Minimum Distance Method and the sand area extraction method by the generalization method as Median filter is suggested to calculate water volume. Finally, mapping process on the sand area extracted from the topographical shape field data in river and satellite images is carried out by the GIS spatial analysis. And on the assumption that the water level was 1m at that time when satellite image was taken, the water volume was $225,258m^3$. It is clarified that the effect of water volume improvement was about 10.5% in comparison with water volume that had no consideration on the gradient characteristics of sand-bar.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.4
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• pp.193-203
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• 2006

This study conducts mapping of the results of topographical dissected degree analysis using GIS and analyzes relation between dissected degree and land use of study area. Application of GIS typographical dissected degree analysis can greatly save time and efforts comparing with traditional manual work, and makes it possible to vary analysis variables widely, which gives possibility to carry out 2-dimensional research using these results. This study, taking start from such background, tries to find the way to carry out dissected degree analysis with the use of GIS, compares the results of the analysis with the land use map, and tries to find the ways of practical application of this analysis results. The results of analysis of the relation between basin dissected degree and agricultural land use of Gangneungnamdae river study area show that for agricultural land use topographical dissection is mostly distributed in quite developed area. Specifically, land used for paddy and dry fields appeared to have higher level of correlation with dissection degree. When comparing dissected degree and agricultural land use interrelation for each area, comparison of intensively formed urban districts with suburbs showed low correlation.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.2 s.20
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• pp.67-75
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• 2002

Recently, GIS tend to be studied in water resoruces field. In hydrology analysis, GIS propose way that can develop subjective element of designer objectively. The development project is conducting disaster effect estimation to breed disaster, and cope these disaster beforehand provoking soil erosion and food recently. In this study, receive value of LS factor through DEM data at volume of soil erosion computation by disaster effect estimation and whether it are some relation effect of gradient and change of soil erosion by grid size did comparative analysis. As a result, according as grid size great, gradient became slow and could know that error value of gradient great according as storing scale of digital topographical map grows.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.11
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• pp.1737-1742
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• 2001

The fractal-based method for describing rubbed surface texture has aroused great interest. The determination of rubbed surface topography is believed to be extremely important in the areas of contact mechanics, adhesion and friction. In order to describe topography of the rubbed surface, the wear test was carried out with annular surfaces of wear testing specimens in dry friction. furthermore, the relation between the fractal dimensions and the frictional conditions are also investigated and fractal descriptors was applied to rubbed surface with image processing. Fractal dimension can be determined by sum of intensity difference of image surface pixel. Fractal dimension increased according as the applied load and sliding distance increase. Topography of the rubbed surface can be effectively obtained by fractal dimensions.

• Journal of Korean Society for Geospatial Information Science
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• v.11 no.3 s.26
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• pp.47-53
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• 2003

Recently, there is studying about slope analysis according to cell size and affect in conformity to determination of hydrologic topographical parameters the cell size a classified map scale about subwatershed. In this study, we wish to offer the base data to determination of hydrologic topographical parameters request of runoff model analysis in this basin on the basis of this results that we compute the CN(curve number) using GIS after classify the map of soil and landuse on the Su-Young River basin. Also, as determination a classified cell size of $100m{\times}100m$ in case of the most optimum size.

• Korean Journal of Ecology and Environment
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• v.41 no.4
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• pp.547-553
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• 2008

In recent years, attention on the inhabitation environments of animals and plants which coexist with humans is growing more and more, and relevant research is being activated. In habitats of rivers, a lot of factors are interacting, even among them, some elements especially such hydraulic factors as water velocity and water depth, and such geological shapes as gravels, sand and mud are being considered as primary elements. In this study, various field investigations are carried out to determine the relationship between the river habitats of fishes and hydraulic primary elements using high-tech equipments. Furthermore numerical experiments to classify such habitats according to topographical spaces are carried out. In detail, hydraulic field investigations performed in this study can be summarized as topographical survey, discharge measurement, water level fluctuation monitoring and so on. In numerical experiments, the RMA2 model of the commercial program, Surface-Water Modeling System (SMS), which is widely used in conducting a two-dimensional analysis of the flow behavior of a river is utilized. In conclusion, as a result of field investigation, the relationship between water velocity and water depth is obtained. And the relationship between water velocity and water temperature is identified, too. Finally, using above obtained results, the inhabitation environment was classified into Riffle, Glide, Run, Pool, and E.D.Z according to the relationship between water velocity and water depth.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.2
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• pp.1-10
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• 2009

Recently the large scale of forest disaster such as landslide and forest fire gives a very bad impact on not only forest ecosystem but also farm business so that it has became the main issue of environmental problems. In this study, the landslide hazard area forecast method was developed by considering not only the topographic thematic maps based on GIS and satellite images but also amount of rainfall data, which are very important factors of landslide. Uljin-gun was selected as the study area and the GIS weight score and overlay analysis were applied to topographical map and meteorological observation map. Finally the landslide area distribution map was constructed by considering the evaluation criteria. Also, the accuracy could be acquired by comparing the landslide hazard area forecast map and real damaged area extracted from satellite image.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.2
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• pp.121-127
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• 2000

Kinematic GPS surveying which can obtain much 3D topographical information through short-time measurement is being utilized mainly in the short baseline less than a few kilometers. Because the decision of position for the long baseline depends on the static GPS surveying which needs long time measurement, the method for measuring the position of long baseline is needed. In this study, the accuracy of the baseline according to the baseline distance, ephemeris, and observation time by GPS surveying is analysed to confirm the application of kinematic GPS surveying for the long baseline. As the result of this, the acquisition of 3D topographical information by GPS surveying in a few minutes will be possible when PDOP is less than 4, and the fast precise ephemeris is used within 60 km. Also, the accuracy is similar to that of final precise ephemeris of IGS. If a lot of studies about the long baseline kinematic GPS surveying are processed, the acquisition of topographical information for various industry including land development will be obtained more efficiently.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.2
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• pp.97-106
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• 2006

Site index is an essential tool to estimate forest productivity. Generally, a site index equation is developed and used from the relationship between stand age and dominant tree heights. However, there is a limit to the use of the site index equation in the application of variable ages, environmental influence, and estimation of site index for the unstocked forest. Therefore, it has been attempted to develop a new site index equation based on various environmental factors including site, climate, and topographical variables. This study was conducted to develop a site index equation based on the relationship between site index and environmental factors for the species of Pinus koraiensis in Yangpyung-Gun, Gyunggi Province. The influence of climatic factors (temperature and solar irradiation ratio), topographical factors (elevation, slope, ratio of slope to valley and aspect) and soil profiles (soil depth by layer and soil consistency) on site index were evaluated by multiple regression analysis. Five environmental factors were selected in the final site index equation for Pinus koraiensis. The site index equation developed in this study was also verified by three evaluation statistics: model's estimation bias, model's precision, and mean square error of measurement. Based on the site index equation, the number of productive areas for Pinus koraiensis were estimated by applying GIS technique to digitized forest maps. In addition, the distribution of productive areas was compared with the areas of current distribution of Pinus koraiensis. It is expected that the results obtained in this study could provide valuable information about the amount and distribution of productive areas for Pinus koraiensis reforestation.