• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.6
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• pp.61-70
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• 2002

This study was performed to analyze the river fractal characteristics using GIS (Geographic Information System). In this study, topographical factors in river basin were grid-analyzed for each cell size and scale using GIS and regression formula was derived by analyzing correlation among topographical factors and cell size which were calculated here. And, a new rainfall-runoff model which is considering the calculated fractal dimension was developed to apply fur a river basin.

• Korean Journal of Ecology and Environment
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• v.49 no.3
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• pp.236-243
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• 2016

It was a case study to use as a basic data for efficient the preservation and management of subalpine coniferous forest in national parks. It is based on inhabitation condition of 210 individuals of Abies koreana Wilson that was found through local investigation in the sub-alpine zone of Jirisan National Park and Songnisan National Park. It analyzed the effect of the geographical location and topographical features, which are the basics of location environment, on the growth of A. koreana. The variables related to the growth of A. koreana are tree height and diameter at breast height. Topographical features include geographical longitude, altitude above sea level, slope of the mountains, aspect that describes the direction in which a slope faces and topographical wetness index. Topographical features were extracted through GIS spatial analysis. It used canonical correlation analysis to estimate whether the two variables groups have related to each other and how much they are related, if any, and estimated the effect of the geographical and topographical features on the growth structure of A. koreana using multiple regression analysis. The tree height and diameter at breast height that represent the growth structure of A. koreana show greater relation to geographical latitude distribution than topographical feature and the geographical and topographical factors show greater relation to diameter at breast height than tree height. The growth structure's variable and geographical and topographical variable of A. koreana have meaningful relation and the result shows that geographical and topographical variables explain 18.1% of the growth structure. The variables that affect the diameter at breast height of A. koreana are geographical latitude, topographical wetness index, aspect and altitude, which are put in order of statistical significance. The higher the latitude is, the smaller the diameter at breast height. Depending on the topographical feature, it becomes bigger. The variable that affects the tree height is topographical wetness index, which was the only meaningful variable. Overall, the tree height and diameter at breast height that are related to the growth structure of A. koreana are affected by geographical and topographical feature. It showed that the geographical feature affected it the most. Especially the effect of water among the topographical features is expected to be bigger than the other topographical factors. Based on the result, it is expected that geographical and topographical feature is an important factor for the growth structure of A. koreana. Even though it considered only the geographical and topographical features and used spatial analysis data produced by GIS, the research results will be useful for investigating and researching the growth environment of coniferous forest inhabiting in sub-alpine zone of national parks and are expected to be used as basic data for establishing measures to efficiently manage and preserve evergreen needleaf tree such as A. koreana.

• Journal of the Korean Association of Geographic Information Studies
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• v.4 no.4
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• pp.51-60
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• 2001

This study analyzed fractal characteristics of river basin by using GIS. In this study, topographical factors in river basin was grid-analyzed for each cell size by using GIS and regression formula was derived by analyzing correlation among topographical factors and cell size which were calculated here. And, analysis of fractal characteristics of river by using the result calculated from 1) showed that among topographical factors, river length only increases according as cell size increases. The result of calculating fractal dimension for each cell size shows that river length, basin area, and centroidal flow path are 1.028, 1.0026 and 1.0061 respectively.

• Journal of The Geomorphological Association of Korea
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• v.25 no.4
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• pp.103-116
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• 2018

The purposes of this research are as follows: First, to reconstruct the optimal locational environment of the Bronze Age settlement in Cheonan Baekseok-dong (hereinafter referred to as the study settlement). Second, to identify the priority ranking of the topographical factors that influenced the Bronze Age people when selecting their the settlement location. For these reasons, the topographical factors of the 200 Bronze Age dwellings (hereinafter referred to as dwellings) confirmed in the survey area were analyzed through the ridge's environmental perspective. The results are asfollows: First, the optimal ridge environment of the Bronze Age settlement is largely a sub-ridge in N-S direction (for example, NNW-SSE, N-S, NNESSW), especially at the top (Crest slope, Crest flat) of the south-facing aspect of the ridge. Second, when the Bronze Age dwellers selected a residential location, they carefully considered topographical factors in the following order: (1) the slope direction of the ridge surface, (2) the micro-landform of the ridge, (3) the ridge scale, (4) the ridge direction, and (5) the surface relief. The results of this study could be used as basic data in related fields such as archaeology, quaternary research, and traditional architecture and so on.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.5
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• pp.335-338
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• 2000

The technology of direct-seeding in rice cultivation is an innovation mainly induced by factors in market economy and is rapidly diffused among individual farmhouses. Because the effect of technology can be affected by many factors under various farming circumstances, the impact and stability of the direct-seeding technology compared with transplanting was analyzed under various topographical regions. Yield in direct-seeding was higher in plains, although the farm size producing higher yield was quite different depending on the topographical regions. In the direct-seeding cultivation of rice, man-labor hours was reduced by about 38 percent and the reduction rate showed little difference among topographical regions. Fertilizer was used about 11 percent more but the increase rate varied from 3 to 17 percent depending on regions with higher rates in plains. Application of agricultural chemicals was also increased about 9 percent in direct-seeding, but the increase rate was as high as 12 percent in suburbs. More fertilizer and agricultural chemicals were used in direct-seeding cultivation by farmhouses implementing both direct-seeding and transplanting than by those implementing direct-seeding only. Use of more fertilizers and agricultural chemicals in direct-seeding in all regions may indicate its technical instability. Major problems causing the technical instability of direct-seeding cultivation should be solved by comprehensive research considering various farming circumstances such as topographical features rather than just a top-down style research and extension.

• Journal of The Geomorphological Association of Korea
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• v.27 no.4
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• pp.89-112
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• 2020

The purpose of this study is as follows: First, we restore the optimal topographical environment of the Bronze Age settlements in the Yongdu Stream and its surrounding area in Asan City. Second, we reveal the relative importance of the topographical factors that the Bronze Age people considered when selecting their dwelling locations. We compared and analyzed topographical factors (ridge scale, ridge direction, slope direction of the ridge, micro-landform of the ridge, position of the ridge) from the ridge's environmental perspective of 123 Bronze Age dwellings (hereinafter referred to as dwellings) found in the survey area for that purpose. The results are as follows: First, from a macro perspective, the optimal topographical environment for the location of the Bronze Age settlement is the second ridge that have the E-W direction. And from a micro perspective, it is the southeast direction slope of the Crest slope at the summit. Second, it appears that the Bronze Age people have taken important consideration in determining the location of their dwelling in the following order: ① position (eg. summit), ② micro-landform (eg. Crest slope, Upper slope), ③ slope direction (eg. southward, South, Southeast), ④ scale (eg. sub-ridge, secondary, tertiary), ⑤ direction (eg. E-W, NNE-SSE).

• Spatial Information Research
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• v.16 no.3
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• pp.359-372
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• 2008

This research estimated Pinus densiflora distribution and suggested an optimal grid size of DEM for ecologically better explaining spatial distribution and appearance pattern of Pinus densiflora and analyze appearance frequency of Pinus densiflora by topographical factors. And this work ultimately aimed at topographically analyzing spatial distribution of Pinus densiflora by comparing impact of topographical factors. The aspect was analyzed in detail, east, west, south, north, from DEM with 1m grid size, and simply, east, west, south or east, south from DEM with bigger grid size. As a result of distribution of Pinus densiflora by aspect, Pinus densiflora appeared in all aspect with smaller grid size, while distribution in specific aspect decreased with bigger grid size. The analysis of appearance frequency with 100m grid size represented spatial distribution characteristics of Pinus densiflora as visual interpretation showed. The results of comparing impact of aspect, slope, TWI proved that aspect have more impact on distribution of Pinus densiflora than slope and there was not enough a difference between impact of slope and TWI.

• 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.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.311-318
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• 1997

On April 27,1993, a forest fire occurred in Morito-area, Manba-city, Gunma-prefecture Japan. Under the prevailing strong winds, the fire spread and extended to the largest scale ever in Gunma-prefecture. The author chartered a helicopter on May 5, one week after the fire was extinguished, and took aerial photos of tile damaged area, and investigated the condition. of the fire through field survey and data collection. The burnt area extended. over about 100 hectares, and the damage amounted to about 190 million yen (about two million dollar). The fire occurred at a steep mountainous area and under strong winds, therefore, md and topography strongly facilitated the spreading, It is the purpose of this paper to report a damage investigation of the fire and to develop the forecasting method of forest fires based on the topographical analysis and spreading speed of fire. In the first place, I analyze the topographical structure of the regions which became the bject of this study with some topographical factors, and construct a land form classification ap. Secondly, I decide the dangerous condition of each region in the land form classification map according to the direction of the wind and spreading speed of f'kre. In the present paper, I try to forecast forest fires in Morito area, and the basic results for the forecasting method of forest fires were obtained with the topographical classification system and spreading speed of fire.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.764-771
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• 2009

This research aimed at analyzing relationship between spatial distribution of Pinus densiflora, and topographical factors in Seorak and Chiak national park. 100 m grid size was proven to be suitable for analyzing spatial distribution characteristics of Pinus densiflora. Pinus densiflora appeared mainly on 400 m~800 m of elevation, $15^{\circ}{\sim}30^{\circ}$ of slope and 0~2 of TWI. There were no big differences in appearance frequency of Pinus densiflora area by aspect. There were differences in distribution characteristics of Pinus densiflora between below and above 400 m of elevation. There were no big differences in appearance frequency of Pinus densiflora area above 400 m of elevation but a big differences by topographical factors below 400 m of elevation.