• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.1138-1140
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• 2005

• Journal of Korea Water Resources Association
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• v.37 no.1
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• pp.1-11
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• 2004

The purpose of this study consists in introducing and examining the previous river classification systems applicable to the river improvement technique including geomorphological considerations, and developing a new system using the geomorphological criteria which represent the morphology of rivers. A newly developed system uses the channel reach as a classifying unit which is delineated by upstream and downstream tributaries. It adopts three basic geomorphological criteria for classification: 1) valley-floor width index(VI) reflecting the confinement of the channel in the valley, 2) sinuosity(P) which expresses the channel planform, and 3) bed material($d_{50}$). The system is composed of 24 stream types. Concerning every stream type, valley forms, principal bed forms and fluvial processes with disturbance elements are briefly presented. Finally, the applicability of this system to the Chungmi Stream and the Imjin River data in comparison with that of Rosgen system is examined.

• Journal of The Geomorphological Association of Korea
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• v.25 no.1
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• pp.97-113
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• 2018

Low-frequency geological natural disaster events such as Pohang earthquake have been occurred. As a results, there's a growing recognition on the importance of education and training for low frequency geological disasters in Korea. In spite of many years of scientific researches on volcanic disaster prevention and preparedness on Baekdusan volcano, the results do not provide the proper scenario for the training for volcanic ash event. Fall 3D volcanic ash diffusion model was run based on wind field data for the last five year, assuming Aso Mountain's explosion with volcanic explosion index 5 for seventy two hours. The management criteria values for proper actions in the previous studies were applied to make a scenario for thirteen groups of the disaster response teams such as train transportation, water supply, electrical facilities and human health. The models on the relationship between education and training for disaster prevention and response were suggested to fulfill the scientific and practical training at local level.

• Journal of The Geomorphological Association of Korea
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• v.20 no.4
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• pp.117-131
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• 2013

2010 eruption of Eyjafjallajokull volcano in Iceland and 2011 Shinmoedake's eruption in Japan evoked concerns from researchers for the possibility of explosion of Baekdusan volcano after long dormancy (repose period). National Emergency Management Administration has tried to evaluate the vulnerability of volcanic disaster and to prepare response to the potential risk and to mitigate the damages from the volcanic eruption, but a few studies have focused on the activities of Baekdusan. This study aims to clarify what the criteria between dormant volcano and active volcano based on geomorphologists' and geologists' researches. Volcanic experts have made a criterion of activeness such as the evidence of volcanic eruption within 10,000 year before present. More rigorous criterion which was made in 1991 by Japanese Meteorological Administration was 2000 years B.P. Both Baekdusan and Hallasan satisfy two criteria, so it is necessary for us to monitor the activity of both volcanoes and to reflect the facts into the curriculum.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.264-267
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• 2004

In identifying flood vulnerable areas, three methods are generally deployed: the geomorphology method which is based on topographic features; the past evidence method based on observed data of past actual floods; and, prediction of flood areas through hydrologic models. This study aims to improve the prediction model of the geomorphology method through the application of fuzzy method in GIS modeling. The generally used GIS method of superimposing thematic map layers assumes crisp boundaries of the layers, which results in either risk-averse solutions or risk-taking solutions. The introduction of fuzzy concepts to processing of evaluation criteria (DEM, slope, aspect) solves this problem. As the result of applying the fuzzy method to a test site in the west Nak-Dong river, similar flood vulnerable areas were predicted as when using the conventional Boolean criteria. The resulting map, however, showed varying degree of uncertainty of flooding in these areas. This extra information is deemed to be valuable in taking phased actions during flood response, leading to a more effective and timely decision-making.

• Journal of The Geomorphological Association of Korea
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• v.21 no.4
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• pp.85-96
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• 2014

A waterfall is a channel unit with steep bedrock. No strict criteria for height, water volume, gradient to define waterfalls exist in Korea. The goal of our study is to classify waterfalls based on morphological forms which are the outcomes of developmental processes. The genesis of waterfall depends upon erosional properties of waterfall. The height, gradient, bedrock strength and stream power of waterfalls are regarded as the main factors, by which waterfalls can be classified. We find out that the most important factor for the development of waterfalls is joint system. Development of joint system varies depending on bedrocks. Flow directions and erosional types are decided by the density and direction of joint system in the bedrock, which also decide the height and gradient of stream bed. Joint type decides the gradients of the bed, gradient and height of waterfalls, therefore, decides morphological forms.

• Journal of The Geomorphological Association of Korea
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• v.19 no.4
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• pp.139-155
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• 2012

Most of previous landform classification methods using DEM compares the values between the center of the cell and the surrounding cells, which in turn, greatly depends on analysis scale. To overcome the problem of scale-dependency, a new classification scheme is developed, which is called "Geomorphons". Unlike the traditional approaches using DEM, Geomorphons is the way which compares the level with other cells against the criteria cell. As a pilot study, we classify the landforms of Pyeongchang-Gun in Korea. Then, we compare the result with the other methods such as Topographic Position Index. Through the systematic analysis, we obtain the following findings. First, Geomorphons can reduce the time for the classification of landforms because of using unsupervised classification. Second, Geomorphons is little dependent on change in the scale, which can provide a pilot tool for reconnaissance study for covering large area.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.592-599
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• 2004

Talus topography is that weathered rock clasts were accumulated dropping in steep slope to action of gravity. Rock fall talus is formed by the accumulation of rock debris falling as individual particles from a cliff. If the collapse is produced in talus slope. it will be possible the loss of manpower and country. Despite correct access about talus is required, domestic research was scientific access about talus short because of short resolution of aerophoto and difficulties of research about huge talus. In this Study, Our research team analgize the wetness index using the geomorphogical data. Lineament through wetness index is simillar with distribution of the talus. And, the aim of the present study is to review and compare fabric data derived from rock fall talus about orientation, distribution and morphology. These deposits tend to have approximately equal amounts of clasts oriented parallel and perpendicular to the dip direction of the slope. And, platy- shaped clasts dominate the proximal and intermediate parts of the talus, wheres blocky-shaped clasts is more common in the distal part. we carry out Rock Fall Simulation. And, We install criteria of the rockfall protective barrier using talus and geomorphological characteristics.

• Journal of The Geomorphological Association of Korea
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• v.25 no.3
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• pp.1-18
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• 2018

In Korea, 64% of the land is known as mountain area, but the definition and classification standard of mountain are not clear. Demand for utilization and development of mountain area is increasing. In this situation, the unclear definition and scope of the mountain area can lead to the destruction of the mountain and the increase of disasters due to indiscreet permission of forestland use conversion. Therefore, this study analyzed the variables and criteria that can extract the mountain boundaries through the questionnaire survey and the terrain analysis. We developed a mountain boundary extraction algorithm that can classify topographic mountain by using selected variables. As a result, 72.1% of the total land was analyzed as mountain area. For the three catchment areas with different mountain area ratio, we compared the results with the existing data such as forestland map and cadastral map. We confirmed the differences in boundary and distribution of mountain. In a catchment area with predominantly mountainous area, the algorithmbased mountain classification results were judged to be wider than the mountain or forest of the two maps. On the other hand, in the basin where the non-mountainous region predominated, algorithm-based results yielded a lower mountain area ratio than the other two maps. In the two maps, we was able to confirm the distribution of fragmented mountains. However, these areas were classified as non-mountain areas in algorithm-based results. We concluded that this result occurred because of the algorithm, so it is necessary to refine and elaborate the algorithm afterward. Nevertheless, this algorithm can analyze the topographic variables and the optimal value by watershed that can distinguish the mountain area. The results of this study are significant in that the mountain boundaries were extracted considering the characteristics of different mountain topography by region. This study will help establish policies for stable mountain management.

• Journal of The Geomorphological Association of Korea
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• v.18 no.2
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• pp.81-98
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• 2011

Among the changes of the Curriculum from the liberation to the present, the biggest change in the highschool geography course appeared during the period from the Period of Syllabus to the 1st National Curriculum. More specifically, during the 1st National Curriculum the highschool geography course which previously had three subjects, 'Natural Environment and Human Lives', 'Human Geography', 'Economic Geography' was reduced to one subject, 'Human Geography.' In addition, while some contents related with astronomy, geology, and biology had been contained in the physiography course, they were left out from the human geography course of the 1st National Curriculum. This reduction of the geography course was related to the context that earth science was newly established in the 1st National Curriculum. Originally the draft plan released in June, 1953, which was 10 months before the formal time allotment criteria list had been made public, contained 'Physical Geography' instead of 'Earth Science'. What is sorry is that the name of 'Physical Geography' did not remain and was changed to 'Earth Science'. The underlying causes of the crisis the geography education is now facing are the reduction of Physical Geography and the emergence of 'Earth Science' during the 1st National Curriculum. To overcome the present crisis, the subject of geography should be changed more meaningful one based on the comprehensive perspective and academic product that geography has accumulated.