• Korean Journal of Remote Sensing
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• v.37 no.6_3
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• pp.1965-1974
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• 2021

Satellite remote sensing approach can be actively used for forest monitoring. Especially, it is much meaningful to utilize Korea multi-purpose satellites, an independently operated satellite in Korea, for forest monitoring of Korea, Recently, several studies have been performed to exploit meaningful information from satellite remote sensed data via machine learning approaches. The forest information produced through machine learning approaches can be used to support the efficiency of traditional forest monitoring methods, such as in-situ survey or qualitative analysis of aerial image. The performance of machine learning approaches is greatly depending on the characteristics of study area and data. Thus, it is very important to survey the best model among the various machine learning models. In this study, the performance of deep neural network to classify artificial or natural forests was analyzed in Samcheok, Korea. As a result, the pixel accuracy was about 0.857. F1 scores for natural and artificial forests were about 0.917 and 0.433 respectively. The F1 score of artificial forest was low. However, we can find that the artificial and natural forest classification performance improvement of about 0.06 and 0.10 in F1 scores, compared to the results from single layered sigmoid artificial neural network. Based on these results, it is necessary to find a more appropriate model for the forest type classification by applying additional models based on a convolutional neural network.

• Journal of Environmental Science International
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• v.23 no.10
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• pp.1673-1691
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• 2014

Although most natural disaster related studies conducted in Korea recently have been related to typhoons or severe rainstorms, the occurrence frequency of disasters due to windstorms or rainstorms is also high. To reduce the strong wind damage caused by strong windstorms due to climate change, basic studies of strong winds are necessary. Therefore, in this study, the types and representative cases of windstorms that were observed to have been higher than 14 m/s, which is the criterion for strong-wind warnings from the Korea Meteorological Administration, were selected from among those windstorm cases that occurred on the Korean Peninsula for 10 years to conduct a statistical analysis of them and determine their synoptic meteorological characteristics. The cases of windstorms occurring on the Korean Peninsula were divided into six weather patterns according to the locations of the anticyclones/cyclones. Among these types, the SH type, which occurs when Siberian Highs expand into the Korean Peninsula, showed the highest occurrence frequency, accounting for at least the majority of the entire occurrence frequency of windstorms together with that of the EC type, which occurs when cyclones develop on the East Sea, and there was no clear yearly trend of the occurrence frequencies of windstorms. The monthly occurrence frequencies of windstorms were formed mainly by typhoons in the summer and the Siberian Highs in the winter, and the months with the highest windstorm occurrence frequencies were December and January, in which mainly the SH and EC type windstorms occurred. March showed the next highest occurrence frequency with10 times, and SH windstorms occurred the most frequently in March, followed by the CC, SC, and EC types of windstorms, in order of precedence. Therefore, attention to these types of windstorms is required. Countermeasures against storm and flood damage in Korea targeting the summer should be re-reviewed together with pre-disaster prevention plans, because cases of storm and flood damage due to windstorms occur more frequently than those due to typhoons, and they occur throughout the year.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.24 no.3
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• pp.299-309
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• 2006

In recent years, a large natural disasters have occurred due to worldwide abnormal weather and the amount of damage has been increased more resulting from high density population and a large-sized buildings of the urbanized area. In this study. we estimate the flooded area according to rainfall probability intensify and sea level in Woreong dong, Masan occurred flood damages by typhoon Maemi using SWMM, a dynamic rainfall-runoff simulation model in urban area, and then analyze the damage of flood expected area through connecting with GIS database. In result, we can predict accurately expected area of inundation according to the rainfall intensity and sea level rise through dividing the study area into sub-area and estimating a flooded area and height using SWMM. We provide also the shelter information available for urban planning and flood risk estimation by landuse in expected flood area. Further research for hazard management system construction linked with web or wireless communication technology expects to increase its application.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.611-614
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• 2009

Understanding the severity of the typhoon-induced storm-surge helps in planning reaction and in preventing further disaster. Natural disasters due to the storm-surge are predictable from accurate observations and forecasts from numerical simulations. What we can do is to make intelligent effort to minimize the loss due to the disaster to the most extent with the technology of early warning, forecast and prevention activity. In this paper, we propose the design of GIS-based Web Service System to visualize the time-varying storm-surge's height and wind field data effectively with 3 different kinds of resolution for predict and prevent storm-surge disasters. This system is one of the efforts to provide the storm-surge forecast service to general public and share two-way more helpful information to coastal resident through the Internet.

• The KIPS Transactions:PartB
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• v.14B no.5
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• pp.329-336
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• 2007

In this paper we propose both the construction of image DB including information on the shooting location and direction of the captured outdoor images and the efficient retrieval method from the DB. Furthermore, for the automatic extraction of the location and direction information, we suggest to have the Digital Camera equipped with an expandable GPS modulo which has a function to calculate the location and direction and also to utilize GPS IFD tags in the EXIF. Then that will make it possible for us to retrieve quickly and precisely the target image with its geography and other objects on the ground included. In the previous retrieval method based only on the location, we eel some extra useless images due to the fact that all the images in the ROI(Region Of Interest) are searched on one condition, radius. However, with the proposed method in this paper, we can not only retrieve all the images selectively within the ROI but also achieve nearly 100% of precision when we search for the target images within DOI(Direction Of Interest) with another condition, direction, added. Applying this method to an image retrieval system, we can classify or retrieve natural images based on the location and direction information, which, in turn, will be vitally useful to diverse industrial fields such as disaster alarm system, fire and disaster prevention system, traffic information system, and so forth.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.1
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• pp.106-119
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• 2016

Flood risk map, flood damage map, disaster information map, inundation trace map are involved with the cartographic analysis of flood inundation based on prevention, preparation, restoration, response from natural disasters such as flood, flooding, etc. In this study, the analysis for channel and basin characteristics Chungju dam to Paldang dam of South han river after four river project. Flood scenario is selected to take advantage of design flood level of schematic design for river. Flood inundation of one dimensional non-uniform flow by using HEC-RAS with basin characteristics is accomplished and two dimensional unsteady flow was interpreted by using FLUMEN. Frequency analysis is carried out about each abundance of South han river for 100 year period, 200 year period and 500 year period. Flooding disaster area of 100 year period on 0.5m damage functions is 2378.8ha, 200 year period on 0.5m damage functions is 3155.2ha, 500 year period on 0.5m damage functions is 3995.3ha respectively. It will be significant data for decision making to establish inundation trace map for providing basic plan for river maintenance, land use plan, flood protection plan, application plan and getting information of flood expectation area.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.2
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• pp.493-500
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• 2011

Recently, there has been an increase in the number of disaster victims locally due to climate change and a variety of frequently occurring natural disasters. The damage caused by abrupt weather change in local area by typical weather forecasting techniques is very limited and difficult. Recently local area weather monitoring system using wireless sensor network technology has been very actively studied. Thus an IEEE 802.15.4-based weather field server to measure and monitor the local weather changes was designed and developed in this study. The proposed weather field server utilizes a wireless sensor node and weather sensors to collect weather information such as temperature, humidity, illumination, dew point, barometric pressure, and water level. The integrated weather sensor board was designed to respond quickly to weather changes, and provide feedback to the server PC. Each weather information is analyzed in the server PC to establish a program to monitor and analyze the local area or the area of abrupt climate change in order to provide warning signals in case of disaster events in local.

• Korean journal of communication and information
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• v.70
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• pp.246-276
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• 2015

From a historical perspective of risk communication, risks can be classified by their associated level of responsibility. In the case of technical risks such as hazardous chemical accidents, people perceive that risk-related organizations have a high level of responsibility; however, they do not in traditional risks such as natural disasters. This study aims to examine risk information seeking and processing, as seen in two types of risk, based on the Risk Information Seeking and Processing(RISP) model. For this purpose, hypotheses and a research question are developed with current domestic risk issues, and the results show significant differences in risk information seeking and processing between the two types of risk. Specifically, in the case of the chemical spill accident, negative emotion against relevant institutions makes different information seeking and processing compared to the natural disaster. The low level responsibility risk such as typhoon comparatively follows the flow of the original RISP model. However, the high level responsibility risk such as the hydrofluoric acid spill did not match with the RISP model. Based on the research results, theoretical implications were discussed.

• Journal of Environmental Science International
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• v.20 no.9
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• pp.1191-1203
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• 2011

In case of Typhoon Dianmu, the temperature, wind speed, wind direction and the rainfall per hour changed dramatically when the center of the typhoon passed through Gimhae. Such a change was commonly found in the regions where the center of the typhoon passed through but almost not in the regions far away from it. For example, in the case of Typhoon Malou where the center of the typhoon was far away from the observation site, such a phenomenon was not observed. The analysis of the vertical observation data showed that there was a little change in the wind speed and wind direction in the vertical direction in the case of Typhoon Dianmu of which center passed through Gimhae. There was a great change in the wind speed according to the height in the lower atmosphere just before the center of the typhoon approached the region. When the center of the typhoon was passing through the region, the vertical wind speed was decreased. However, the wind speed was rapidly increased again after the center of the typhoon had passed through the region. Unlike the Dianmu, the difference in the wind speed and wind direction between the upper layer and lower layer of the atmosphere was relatively great in the case of Malou.

• Journal of Cadastre & Land InformatiX
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• v.47 no.2
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• pp.135-144
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• 2017

The riverbed areas have exposed to various natural disasters and the private use by neighboring residents have caused many problems. The research objectives are to survey the actual situation of riverbed areas in order to prevent landscape damage and private use. Drone and photogrammetry, orthophoto, DSM(Digital Surface Model), digital topographic map and cadastral information have been integrated by GIS technology. The flood and disaster vulnerable area has been surveyed and the land use and private use has been analyzed using cadastral information. The research results show that the analyzed data can be used for providing foundation data for management of river and also can be used for surveying actual situation of private use on the riverbed areas.