• Proceedings of the KSRS Conference
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• v.2
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• pp.539-542
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• 2006

To investigate the streamflow impact of land cover changes by a typhoon, WMS HEC-1 storm runoff model was applied by using land cover information before and after the typhoon. The model was calibrated with three storm events of 1985 to 1988 based on 1985 land cover condition for a 192.7 $km^2$ watershed in northeast coast of South Korea. After the model was tested, it was run to estimate impacts of land cover change by the typhoon RUSA occurred in 2002 (31 August - 1 September) with 897.5 mm rainfall. The land covers before and after the typhoon were prepared using Landsat 7 ETM+ of September 11 of 2000 and Landsat 5 TM of September 29 of 2002 respectively. For the 6.9 $km^2$ damaged area (3.6 % of the watershed), the peak runoff and total runoff by the changed land cover condition increased 12.5 % and 12.7 % for 50 years rainfall frequency and 1.4 % and 1.8 % for 500 years rainfall frequency respectively based on AMC (Antecedent Moisture Condition)-I condition.

• Korean Journal of Remote Sensing
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• v.22 no.5
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• pp.407-413
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• 2006

To investigate the streamflow impact of land cover changes by a typhoon, HEC-l storm runoff model was applied by using land cover information before and after the typhoon. The model was calibrated with three storm events of 1985 to 1988 based on 1985 land cover condition for a $192.7km^{2}$ watershed in northeast coast of South Korea. After the model was tested, it was run to estimate impacts of land cover change by the typhoon RUSA occurred in 2002 (31 August-1 September) with 897.5 mm rainfall. The land covers before and after the typhoon were prepared using Landsat 7 ETM+ of September 11 of 2000 and Landsat 5 TM of September 29 of 2002 respectively. For the $6.9km^{2}$ damaged area (3.6 % of the watershed), the peak runoff and total runoff by the changed land cover condition increased 12.5 % and 12.7 % for 50 years rainfall frequency and 1.4 % and 1.8 % for 500 years rainfall frequency respectively based on AMC (Antecedent Moisture Condition)-I condition.

• Journal of Korean Society of Rural Planning
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• v.16 no.2
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• pp.31-45
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• 2010

Building a dam that is not considering the environmental impact and human social impact can cause the loss of entire ecospheres such as fragmentary green network, disturbance of plants ecosystem, the destruction of social and cultural indigenous resources, therefore, it can occur the environment change and distortion of ecosystem. The purpose of this study is that presenting the methods of ecosystem maintenance and ecosystem damage compensation about for environmentally direct impact i.e. the ecosystem change in the intended place for building a dam. According to the planning progress, the study was proceeded to planning site examine, assessment, conception plan. As the results of examine and assessment, it must be necessary to offered the maintenance and damage compensation if the site where include the 1st degree of biotope area, the 2nd degree of biotope and the 8th degree of green naturality area were damaged by being submerged and constructing road. In addition, according to the conception plan, we suggest the mitigation proposals such as plant communities transplant, planning of connecting green network against for influencing direct impact ecosystem that is destroying plant communities, damaging inhabitants, noise pollution, water pollution, etc.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.1
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• pp.25-34
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• 2017

The objective of this study is to seek for improvement measures to make the Ecosystem and Nature Map by analyzing causes for grade changes and distributional characteristics of areas with public objections to the Ecosystem and Nature Map notified by e-official gazette from 2014 to June 2016. The receipt of public appeals has been recently increased from average 23 cases a year(2007-2013) to average 33 cases a year(2014-June 2016) while there were 42 areas with public appeals for less than the minimum area($62,500m^2$) for the evaluation of grade of the Ecosystem and Nature Map. Most of the public appeals focused on the 1st grade zone of the Ecosystem and Nature Map. Before grade changes by public appeals, the 1st grade zone of the Ecosystem and Nature Map were 76.0% of the whole areas with public appeals. However, after grade changes by public appeals, it was rapidly decreased to 25.2%, which means that a lot of the 1st grade zone with public appeals were lowered. In the results of analyzing the distributional characteristics of areas with public appeals, they were mostly distributed in lowland(less than 250m altitude), section with $10{\sim}20^{\circ}$ slope, and areas close to or within 100m from built-up area. Regarding areas with public appeals, the biggest time difference between the period of the existing research by National Ecosystem Survey and the period of notice after completing the treatment of public appeals was 18 years while areas showing 6-15 years of time difference were about 70%. Thus, there were huge differences in time of research and notice. Also, the biggest causes for grade changes were boundary errors caused by small-scale survey, and then followed by changes in evaluation of endangered species and occurrence of built-up area and damaged land. Analyzing areas with public appeals in each evaluation item of the Ecosystem and Nature Map, vegetation part was 73.0%, and endangered species area was 23.1% while topography and wetland was less.

• Journal of Environmental Impact Assessment
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• v.21 no.1
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• pp.1-13
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• 2012

We diagnosed on status and problems of environmental assessment regarding development of offshore wind power, and also on reasonable core assessment items. Most of the coastal wind power are located on the western coastline of Korea and Jeju Island. In the selections of the site for the offshore wind farms, a previous investigations should be conducted with regard to distances from the land, stabilities from external forces (tide, wave, etc.) and topographical changes, and characteristics of the surroundings (distributions of protected area, fishing ground, artificial seagrasses, and shipping traffic). It is needed to assess dispersion of suspended solids, changes of the sea bottom, and impacts on fisheries resources and fishing activities under construction of offshore wind power. Furthermore, the responses of marine organisms to noise and vibration, impacts by electromagnetic fields, impacts on sea birds, hindrances to sea lane routes, and damaged scenery and marine protection areas are thoroughly assessed during operation processes. The consultation criteria in case of development of offshore wind farm is adjusted by focusing marine environmental impact assessment.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.3
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• pp.220-225
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• 2013

Accidents between ships occur frequently at the traffic congestion area. Once a maritime accidents occur, it is likely to end up with critical damaged accidents. This paper develop a simulator for assessing quantitative risk based on statical maritime traffic data and realtime traffic distribution. Ship's passage risk assessment simulator consist of import of division of passage data, traffic distribution analysis and passage risk assessment analysis. Maritime traffic data of WANDO waterway apply to simulator for calculation of quantitative risk rate of waterway.

• Journal of the Earthquake Engineering Society of Korea
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• v.27 no.6
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• pp.265-273
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• 2023

This study proposes a methodology for the regional seismic risk assessment of structural damage to buildings in Korea based on evaluating individual buildings, considering inconsistency between the administrative district border and grid lines to define seismic hazard. The accuracy of seismic hazards was enhanced by subdividing the current 2km-sized grids into ones with a smaller size. Considering the enhancement of the Korean seismic design code in 2005, existing seismic fragility functions for seismically designed buildings are revised by modifying the capacity spectrum according to the changes in seismic design load. A seismic risk index in building damage is defined using the total damaged floor area considering building size differences. The proposed seismic risk index was calculated for buildings in 29 administrative districts in 'A' city in Korea to validate the proposed assessment algorithm and risk index. In the validation procedure, sensitivity analysis was performed on the grid size, quantitative building damage measure, and seismic fragility function update.

• Journal of Environmental Impact Assessment
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• v.15 no.4
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• pp.237-247
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• 2006

In case of studied area located around the sea, the data measured from the regional meteorological office is highly different from the local weather data because the diffusivity of fugitive dust varies considerably with meteorological conditions. Especially, it is very difficult to predict the amount of fugitive dust accurately as wind speed remains high frequently. In this study, the fluxes of suspended particulates as a function of the friction velocity were applied to consider the effect of wind speed on the amount of fugitive dust generated from the reclamation site. The amount of fugitive dust estimated as mentioned above was simulated by using ISCST3 model. As a result, in case of using only the Fugitive Dust Formula which is usually used in Environment Impact Assessment, the predicted $PM_{10}$ concentrations with points were $43.4{\sim}67.8{\mu}g/m^3$. However, in case of applying to the flux of suspended particulates, the predicted values of $PM_{10}$ with points were $43.3{\sim}69.1{\mu}g/m^3$, $49.5{\sim}90.4{\mu}g/m^3$ and $76.0{\sim}182.6{\mu}g/m^3$ with the wind speeds of 4.4, 5.8 and 7.7m/s, respectively. It could be possible to predict the amount of fugitive dust accurately because these predicted values were similar to the measured values. Consequently, we can establish alternatives for reduction of fugitive dust in this area damaged by fugitive dust which is caused by wind.

• Composites Research
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• v.27 no.2
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• pp.77-81
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• 2014

In this study, it was performed damage assessment and repair of small scale aircraft adopted on composite. This aircraft adopted the sandwich structure to skin of wing. This study aims to investigate the residual strength of sandwich composites with nomex honeycomb core and carbon fiber face sheets after the open hole damage by the experimental investigation. The 4-point bending tests were used to find the bending strength, and the open hole was applied to introduce the simulated damage on the specimen. The bending strength test results after open hole were compared with the results of no damaged specimen test. In addition, The damaged composite structure was repaired using external patch repair method after removing damaged area. After that, this study presents comparison results of the experimental investigation between the damaged and the repaired specimen. It was found that the bending strength of repaired specimen was recovered up to 95% of undamaged specimen.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.3
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• pp.67-73
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• 2009

Financial supports of private facilities which were damaged by natural disaster are currently performed partially by a government and the guideline of corresponding recovery costs be the natural disaster prevention law in South Korea. However, current financial recovery guidelines for the damaged private facilities has not been estimated objectively so far. This research presents advanced recovery cost search and assesment methods for the damaged private facilities under natural disaster. To produce more accurate data, an investigation for practical field markets which are appointed in Kangwon area is conducted and the proposed recovery values per each item are compared to exact field market values. Finally. more realistic and accurate recovery cost guideline including evaluation and more effective market surveying method are suggested here. A theoretical and practical program for systematic recovery cost calculation is proposed and expected to be used at public institution before long.