• Journal of The Geomorphological Association of Korea
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• v.28 no.3
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• pp.13-26
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• 2021

In mountain gully, channelized debris flow is an important phenomenon in the process of topographical change. Social infrastructure as roads may be damaged by channelized debris flows, but there has been little information about their occurrence and movement to prepare for the risk of the debris flow. Most of the channelized debris flows occur during heavy rains in mountainous valleys that are difficult to access, so there are not many field data. In this study, the topographical characteristics of the catchment, the rainfall and runoff related to the debris flow, the sedimentary pattern and the cross-sectional change of the channel bed, and the underflow velocity of the gravel bed have been investigated and analyzed in the Singi gully where the channelized debris flows occurred. In the catchment, there was almost no sediment runoff because the vegetation combine with the debris landforms and covered the surface. Therefore, the obvious cause of the channelized debris flows is the collapse of the slope and bed of the gully. Even if the gravel, cobbles, and boulders of the channel bed were lost by debris flow, the thalweg change due to debris flow may not be significant because they are supplied from the gully side slope normally. After the gabion structures were installed, the debris flow increased the thalweg change, bed erosion and side slope of the gully. Various sedimentary structures in the gully were classified according to the factors supporting the sedimentation. The hypsometric curve of the gully reflects the debris landforms and vegetation characteristics of the watershed and the sediment runoff due to debris flow, etc. The relationship between the flow velocity and the hydraulic gradient was non-linear under the condition that the porous medium with gully bed gravels is saturated with water. These results may be used as basic data for channelized debris flow research.

• Journal of Korea Water Resources Association
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• v.53 no.12
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• pp.1193-1201
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• 2020

This study aims to develop a regression model that estimates a low-flow index that can be applied to ungauged basins. A total of 30 midsized basins in South Korea use long-term runoff data provided by the National Integrated Water Management System (NIWMS) to calculate average low-flow, average minimum streamflow, and low-flow index duration and frequency. This information is used in the correlation analysis with 18 basin factors and 3 climate change factors to identify the basin area, average basin altitude, average basin slope, water system density, runoff curve number, annual evapotranspiration, and annual precipitation in the low-flow index regression model. This study evaluates the model's accuracy by using the root-mean-square error (RMSE) and the mean absolute error (MAE) for 10 ungauged, verified basins and compares them with the previous model's low-flow calculations to determine the effectiveness of the newly developed model. Comparative analysis indicates that the new regression model produces average low-flow, attributed to the consideration of varied basin and hydrologic factors during the new model's development.

• Journal of the Korean Society of Safety
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• v.20 no.4 s.72
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• pp.171-179
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• 2005

It is essential to understand the role of wall lining materials when they are exposed to a fire from an ignition source. Full-scale test methods permit an assessment of the performance of a wall lining material. Fire growth models have been developed due to the costly expense associated with full-scale testing. The models require heat flux maps from the ignition burner flame as input data. Work to date was impeded by a lack of detailed spatial characterization of the heat flux maps due to the use of limited instrumentation. To increase the power of fire modeling, accurate and detailed heat flux maps from the ignition burner are essential. High level spatial resolution for surface temperature can be provided from an infrared camera. The objective of this study was to develop a heat flux mapping procedure for a room test burner flame to a wall configuration with surface temperature information taken from an infrared camera. A prototype experiment was performed using the ISO 9705 test burner to demonstrate the developed heat flux mapping procedure. The results of the experiment allow the heat flux and spatial resolutions of the method to be determined and compared to the methods currently available.

• The Journal of Engineering Geology
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• v.26 no.1
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• pp.129-142
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• 2016

National parks, which are located mainly in mountainous areas, are always at risk of damage by landslides. The goal of this study is to establish a method for systematically maintaining hazardous steep slopes along trails in national parks. We produced a checklist suitable for each of the 19 national parks nationwide and investigated 183 slopes. The aim of these investigations is to recommend appropriate slope-stability countermeasures, including field investigations and stability analysis. We made preliminary investigations at specific sites, evaluating the slope hazard using specialized equipment such as terrestrial LiDAR. An investment priority formula was developed, and ranking and hazardous grades were calculated as part of a long-term maintenance plan. Finally, to systematically manage dangerous slopes and to house all the field data within one system, we developed the "Slope Maintenance System in National Parks" based on web server that can show various information for slopes.

• Journal of Environmental Health Sciences
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• v.38 no.2
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• pp.166-174
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• 2012

Introduction: After 17 years since the first production of humidifier disinfectants in Korea, Korea Centers for Disease Control and Prevention (KCDC) announced that the odds ratio of lung injury related with humidifier disinfectant usage was 47.3 (95% confidence interval 6.0-369.7) according to a case-control study with 18 adult cases, including 8 pregnant women at a university hospital in Seoul. Results: From September 2011 to April 2012, one-hundred and seventy four victim cases have been reported to an environmental non-governmental group (NGO). We summarized timetable of humidifier disinfectants accidents, analyzed health outcomes (death, lung or lung and heart transplantation, pulmonary disease) of reported victims, and classified some information for humidifier disinfectants with health outcomes, and government action for this accident. Among the victims, number of death cases are 52 (30.0%), including 26 babies less than 3 years old. Sixty-nine victims come from twenty-seven family with 2 to 4 members per family. About twenty types of humidifier disinfectant products and about 600,000 product items a year have been sold. Fifty-two death cases used 7 different types of disinfectant products, including imported goods and some private brands of well-known supermarkets. KCDC confirmed inhalation toxicity of 6 products through an animal experimental test, and based on this observation recalled disinfectants containing PHMG (polyhexamethylene guanidine) and PGH (Oligo(2-(2-ethoxy)ethoxyethyl guanidinium chloride). Discussions: The use of these biocides involved highly fatal consequences among biologically vulnerable victims, such as pregnant women, several family member victims after semi-acute exposure. This is the first biocide disaster in Korea with non-specific targets, and unknown scale of victims, warranting concerns on use of biocides in the living environment. Conclusions: Special administrative agency for chemical safety and compensation act for environmental health victims are needed to prevent similar problems.

• Journal of Pharmacopuncture
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• v.19 no.4
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• pp.344-349
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• 2016

Objectives: This study aimed to determine the knowledge levels and attitudes of School of Health and Vocational School of Health students toward complementary and alternative medicine (CAM). Methods: Three hundred thirty-three (333) students studying at the Mehmet Akif Ersoy University School of Health and the Golhisar Vocational School of Health in Burdur, Turkey, were included in the study. Research data were collected by using a survey method based on the expressed opinions of the participants. Results: Of the participants, 69.7% were female and 97% were single (unmarried). Of cigarette users and those with chronic illnesses, 46.8% and 47.8%, respectively, used CAM. Those using CAM were statistically more likely to be female (P < 0.021), to have higher grades (P < 0.007), to be single (P < 0.005), to be vocational school of health graduates (P < 0.008), and to have fathers at work (P < 0.021). While 9.6% of the students thought CAM to be nonsense, 10.8% thought that the methods of CAM should be tried before consulting a doctor. Conclusion: A majority of the students in the study population were found to use complementary and alternative medicine, but that they lacked information about its methods. As a way to address this, CAM should be included in the curriculum of schools that provide health education, and CAM training programs should be given to healthcare professionals to improve their knowledge of CAM. In Turkey, many more studies should be performed to determine nurses' and doctors' knowledge of and attitudes about CAM methods so that they can give correct guidance to society and take more active responsibility in improving patient safety.

• Journal of the Society of Disaster Information
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• v.16 no.1
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• pp.163-177
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• 2020

Purpose: While it is very important to maintain facilities recently, the introduction and its application of high technology in the facility maintenance industry has increased. It is necessary for high technology to secure reliability through the verification and certification system of diagnostic equipment to have an effective impact in the field, but there is difference between the industry's perspective and realistic level of technology apart from social demand for the system of the system. This paper dealt with the introduction of a verification and certification system for rational facility diagnostic equipment with the opinion survey on managers about the current situation. Method: Survey is carried out targeting managers in the maintenance and construction regarding the necessity and urgency of introducing a verification and certification system to promote the introduction and its application of high technology of diagnostic equipment and facility inspection. Also, the introduction to a verification and certification system was reviewed for advanced facility diagnostic equipment through foreign research about similar systems and comparative analysis of similar systems related to the certification of 21 domestic equipment. Result: It showed that, regarding the application of high technology, it is necessary for most managers to introduce high technology such as drones, robots, etc., in the maintenance industry, and when high technology is introduced, it will have a considerable effect in the field. On the other hand, the current technology level in Korea is relatively low, so it turned out to take a certain amount of time for the application of technology. Also, it was found that the management of reliable facility diagnostic equipment will be possible through the introduction of the verification and certification system for facility diagnosis equipment. Meanwhile, the survey is conducted on similar systems about foreign and domestic diagnosis and measuring equipment, etc., but there is no system to verify and certify equipment applied with high technology directly to facility diagnosis maintenance. However, because Japan has a system of verifying the performance of diagnostic equipment and South Korea has 21 similar inspection and diagnostic equipment certification systems among 186 certification systems, it is considered to be possible to design systems which utilize them. Conclusion: According to the managers' opinion, it seems that the introduction of the system supporting the application of 4th industrial technology for the equipment and the use of the equipment with high reliability has sufficient validity. However, because our high technology level is undervalued compared to the urgency, the system for checking high technology facilities and certifying diagnostic equipment should be to be implemented in form of escalation considering technical use and verification level. Apart from the introduction of the verification and certification system, it is necessary for special investment, support and efforts to promote advanced facility diagnostic equipment.

• Journal of Radiation Protection and Research
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• v.48 no.2
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• pp.68-76
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• 2023

Background: In the process of discussion on the possibility of using radionuclide-contaminated soil and debris generated by radiation disasters, a strategy for the proper management of radiation exposure protection while considering the source of the contaminated materials is necessary. Materials and Methods: The radiological protection criteria that are likely to be applied to the source-related approach based on the International Commission on Radiological Protection recommendations and the International Atomic Energy Agency safety standards are summarized. We proposed five interpretations of radiation protection to contribute to the promotion of discussion on the possibility of using a part of low-level-radionuclide-contaminated soil and debris in the post-accident rehabilitation. Interpretations I to III are based on the idea of "using a reference level to protect the public in post-accident rehabilitation," whereas IV and V are based on the idea of "using the dose constraint to protect the public in the post-accident rehabilitation when the sources are handled in a planned activity." The former idea is subdivided into three based on the definition of the source, which is managed by the reference level, and the latter idea is divided into two depending on whether or not additional dose from using contaminated materials is deemed acceptable. Results and Discussion: To confirm the applicability of the five interpretations presented, we suggested the concrete values of protection criteria via two feasible cases. In this case study, we proposed radiation protection by the dose constraint based on the Interpretation IV and chose 1 mSv/yr for the public and 20 mSv/yr for workers dealing with radionuclide-contaminated materials. Conclusion: We concretely and systematically demonstrated how the concept of radiation protection can be applied to the process of discussion on the possibility of using radionuclide-contaminated materials within the framework of an international system of protection. This study's findings can provide necessary information to discuss the possibility of using radionuclide-contaminated materials as an alternative option for recovery and reconstruction after a radiation disaster from the viewpoint of radiation protection.

• Journal of Environmental Impact Assessment
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• v.20 no.5
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• pp.705-716
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• 2011

For the efficient discovery of knowledge and information from the observed systems, data mining techniques can be an useful tool for the prediction of water quality at intake station in rivers. Deterioration of water quality can be caused at intake station in dry season due to insufficient flow. This demands additional outflow from dam since some extent of deterioration can be attenuated by dam reservoir operation to control outflow considering predicted water quality. A seasonal occurrence of high ammonia nitrogen ($NH_3$-N) concentrations has hampered chemical treatment processes of a water plant in Geum river. Monthly flow allocation from upstream dam is important for downstream $NH_3$-N control. In this study, prediction models of water quality based on multiple regression (MR), artificial neural network and data mining methods were developed to understand water quality variation and to support dam operations through providing predicted $NH_3$-N concentrations at intake station. The models were calibrated with eight years of monthly data and verified with another two years of independent data. In those models, the $NH_3$-N concentration for next time step is dependent on dam outflow, river water quality such as alkalinity, temperature, and $NH_3$-N of previous time step. The model performances are compared and evaluated by error analysis and statistical characteristics like correlation and determination coefficients between the observed and the predicted water quality. It is expected that these data mining techniques can present more efficient data-driven tools in modelling stage and it is found that those models can be applied well to predict water quality in stream river systems.

• KNOM Review
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• v.22 no.3
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• pp.25-30
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• 2019

For meteorological applications, meaningful results must be derived and provided within time and resource limits. Forecasts through numerous historical data are time-consuming and still have resource limitations in the case of disaster safety-related analyses/predictions such as local typhoon forecasts. Suitable forecasts should be provided without any problems caused by limited physical environmental conditions and when results are to be drawn under time constraints, such as typhoon forecasts and forecast services for flooded areas by road. In this paper, we analyze the application of weather and climate forecasting to provide a suitable forecasting service in both temporal and resource conditions. Through the analysis of execution time according to mesh sizes, it was confirmed that a mesh adjustment can cope with the case of the temporal constraint. In addition, by analyzing the execution time through memory resource control, we confirmed the minimum resource condition that does not affect the performance and the resource usage pattern of the application through the swap and mlock analysis.