• Journal of the Korean Society of Earth Science Education
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• v.12 no.3
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• pp.291-301
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• 2019

The purpose of this study is to develop HTE-STEAM program using natural disasters for high school students and to verify their attitude and satisfaction with STEAM. We developed the HTE-STEAM program utilizing natural disasters and tested the effectiveness of 243 students from G High School and N High School. For data analysis, a single group pretest and post response t-test were conducted to verify the effects on attitudes and satisfaction with STEAM. The research results are as follows. First, we developed STEAM education programs for high school students by selecting the topic of "natural disasters" in the area of earth science and flying drones as lifesaving drones. The six-hour program was designed to give students the experience to solve problems by applying essential knowledge related to natural disasters and drones, and what they learned in other situations. Second, there was a significant statistical test result in the t-test of the corresponding sample by the difference between the pre and post score of the STEAM attitude test (p <.05). The drone-based HTE-STEAM program had a significant improvement in the overall attitude toward STEAM education, which consists of seven subfactors. Third, in the HTE-STEAM satisfaction test, the average value of the lower job offer was 3.64 ~ 3.76, which showed a positive response overall. It is judged that the students' satisfaction is improved through the students' understanding of the problem situation and the design of creative convergence and production process.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.3
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• pp.52-66
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• 2017

This study aims at designing standard metadata that can be incorporated for advanced utilization of damage prediction maps, and thereby constructing the standard meta-information management prototype system on the basis of the proposed design. Based on the ISO/TC 211 19115 international standard, which is considered as the most widely used standard (as per the results of a domestic and foreign metadata standard survey), the designing process for the standard metadata was established and the metadata was categorized into nine classes. Additionally, based on the output of the standard metadata design process, a standard meta-information management prototype system, capable of checking and downloading meta-property information, was constructed using the JAVASCRIPT language. By incorporating the obtained results, it is possible to maintain the quality of the constructed damage prediction map by establishing a standardized damage prediction map database. Furthermore, disaster response can be actuated through the provision and management of data for effective operation of the proposed damage prediction system.

• Journal of the Society of Disaster Information
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• v.9 no.4
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• pp.449-461
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• 2013

As the hydrofluoric acid leak in Gumi-si, Gyeongsangbuk-do or hydrochloric acid leak in Ulsan, Gyeongsangnam-do demonstrated, chemical related accidents are mostly caused by large amounts of volatile toxic substances leaking due to the damages of storage tank or pipe lines of transporter. Safety assessment is the most important concern because such toxic material accidents cause human and material damages to the environment and atmosphere of the surrounding area. Therefore, in this study, a hydrofluoric acid leaked from a storage tank was selected as the study example to simulate the leaked substance diffusing into the atmosphere and result analysis was performed through the numerical Analysis and diffusion simulation of ALOHA(Areal Location of Hazardous Atmospheres). the results of a qualitative evaluation of HAZOP (Hazard Operability)was looked at to find that the flange leak, operation delay due to leakage of the valve and the hose, and toxic gas leak were danger factors. Possibility of fire from temperature, pressure and corrosion, nitrogen supply overpressure and toxic leak from internal corrosion of tank or pipe joints were also found to be high. ALOHA resulting effects were a little different depending on the input data of Dense Gas Model, however, the wind direction and speed, rather than atmospheric stability, played bigger role. Higher wind speed affected the diffusion of contaminant. In term of the diffusion concentration, both liquid and gas leaks resulted in almost the same $LC_{50}$ and ALOHA AEGL-3(Acute Exposure Guidline Level) values. Each scenarios showed almost identical results in ALOHA model. Therefore, a buffer distance of toxic gas can be determined by comparing the numerical analysis and the diffusion concentration to the IDLH(Immediately Dangerous to Life and Health). Such study will help perform the risk assessment of toxic leak more efficiently and be utilized in establishing community emergency response system properly.

• Journal of Korea Water Resources Association
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• v.49 no.6
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• pp.519-528
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• 2016

Frequently torrential rain is occurred by climate change and urbanization. Urban is formed with road, residential and underground area. Without detailed topographic flooded analysis consideration can take a result which are wrong flooded depth and flooded area. Especially, flood analysis error of population and assets in dense downtown is causing a big problem for establishments and disaster response of flood measures. It can lead to casualties and property damage. Urban flood analysis is divided into sewer flow analysis and surface inundation analysis. Accuracy is very important point of these analysis. In this study, to confirm the effects of the elevation data precision in the process of flooded analysis were studied using 10m DEM, LiDAR data and 1:1,000 digital map. Study area is Dorim-stream basin in the Darim drainage basin, Sinrim 3 drainage basin, Sinrim 4 drainage basin. Flooding simulation through 2010's heavy rain by using XP-SWMM. Result, from 10m DEM, shows wrong flood depth which is more than 1m. In particular, some of the overflow manhole is not seen occurrence. Accordingly, detailed surface data is very important factor and it should be very careful when using the 10m DEM.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.407-416
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• 2020

North Korea's demand for infrastructure construction and maintenance is growing rapidly. On the other hand, the number of skilled workers is insufficient. Therefore, through a survey of North Korean defectors, this study analyzed the status of construction technology and the difficulties of construction workers. In addition, an attempt was made to derive an appropriate education and training program process and operation plan. As a result of the survey, the reason for the low technical level of construction workers was the lack of skills, lack of motivation to work, and the lack of training and management systems. The appropriate education and training period was 56% of the total response within one year and 36% within six months. Based on the results of this survey, the period of education and training for the rapid training of construction technical personnel in North Korea was adopted as one year. Moreover, compared to the NCS standard in South Korea, appropriate training hours were suggested, excluding training courses, such as planning and design, construction management that require specialized knowledge. Finally, the curriculum corresponding to the education and training courses and the standards for facility names and required areas for facility operation were suggested.

• Fire Science and Engineering
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• v.30 no.6
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• pp.48-56
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• 2016

A crude oil leakage from a large atmospheric storage tank occurred on 4 April 2014 at 14:50 in Ulsan City, while storing the crude oil in the tank. Emergency Rescue Control Group was deployed in the scene. The company, Fire Service Headquarters and associated agencies got together in Command Post (CP) for discussing an effective corresponding strategy. Many solution plans were drafted in the debate such as power down, stopping the facilities, checking the density of inflammable gas, suppressing oil evaporation, moving the leaked crude oil to a nearby tank and a processing plant and avoiding marine pollution. All the solutions were carried out in cooperation with several agencies and partners. The oil leakage accident was successfully settled up within the process of responding, The Fire Service Headquarters and the company thought that the most important thing was the suppression of oil evaporation and the elimination of ignition source. With Fire Service Headquarters and several agencies' every effort, an explosion and a fire didn't occurred in the scene. This study suggest the improvement of the operating system in Emergency Rescue Control Group in case of petroleum leakage, explosion and fire accidents of atmospheric storage tank, different from a ordinary disaster. Assuming that petroleum leakage in atmospheric storage tank develop the explosion and fire accidents, the spreading speed of the flame and the burning time was experimented and compared with each other. Furthermore, this study concentrates on the effective field response plan prepared for the afterward explosion and fire accidents from petroleum leak in a storage tank, with the database experimented and analyzed in accordance with the angle of radiation in the foam nozzle and the pressure of pumping in a fire engine.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.34 no.3
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• pp.137-149
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• 2021

Cable-stayed bridges are infrastructure facilities of a highly public nature; therefore, it is essential to ensure operational safety and prompt response in the event of a collapse or damage caused by natural and social disasters. Among social disasters, impact accidents can occur in bridges when a vehicle collides with a pier or when crashes occur due to aircraft defects. In the case of offshore bridges, ship collisions will occur at the bottom of the pylon. In this research, a procedure to evaluate the structural behavior of a cable-stayed bridge for aircraft impact is suggested based on a numerical analysis approach, and the feasibility of the procedure is demonstrated by performing an example assessment. The suggested procedure includes 1) setting up suitable aircraft impact hazard scenarios, 2) structural modeling considering the complex behavior mechanisms of cable-stayed bridges, and 3) structural behavior evaluation of cable-stayed bridges using numerical impact simulation. It was observed that the scenario set in this study did not significantly affect the target bridge. However, if impact analysis is performed through various scenarios in the future, the load position and critical load level to cause serious damage to the bridge could be identified. The scenario-based assessment process employed in this study is expected to facilitate the evaluation of bridge structures under aircraft impact in both existing bridges and future designs.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1211-1224
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• 2023

Clouds cause many difficult problems in observing land surface phenomena using optical satellites, such as national land observation, disaster response, and change detection. In addition, the presence of clouds affects not only the image processing stage but also the final data quality, so it is necessary to identify and remove them. Therefore, in this study, we developed a new cloud detection technique that automatically performs a series of processes to search and extract the pixels closest to the spectral pattern of clouds in satellite images, select the optimal threshold, and produce a cloud mask based on the threshold. The cloud detection technique largely consists of three steps. In the first step, the process of converting the Digital Number (DN) unit image into top-of-atmosphere reflectance units was performed. In the second step, preprocessing such as Hue-Value-Saturation (HSV) transformation, triangle thresholding, and maximum likelihood classification was applied using the top of the atmosphere reflectance image, and the threshold for generating the initial cloud mask was determined for each image. In the third post-processing step, the noise included in the initial cloud mask created was removed and the cloud boundaries and interior were improved. As experimental data for cloud detection, CAS500-1 L2G images acquired in the Korean Peninsula from April to November, which show the diversity of spatial and seasonal distribution of clouds, were used. To verify the performance of the proposed method, the results generated by a simple thresholding method were compared. As a result of the experiment, compared to the existing method, the proposed method was able to detect clouds more accurately by considering the radiometric characteristics of each image through the preprocessing process. In addition, the results showed that the influence of bright objects (panel roofs, concrete roads, sand, etc.) other than cloud objects was minimized. The proposed method showed more than 30% improved results(F1-score) compared to the existing method but showed limitations in certain images containing snow.