• Korean Journal of Remote Sensing
• /
• v.38 no.5_3
• /
• pp.925-938
• /
• 2022

Agricultural reservoirs are an important water resource nationwide and vulnerable to abnormal climate effects such as drought caused by climate change. Therefore, it is required enhanced management for appropriate operation. Although water-level tracking is necessary through continuous monitoring, it is challenging to measure and observe on-site due to practical problems. This study presents an objective comparison between multiple AI models for water-body extraction using radar images that have the advantages of wide coverage, and frequent revisit time. The proposed methods in this study used Sentinel-1 Synthetic Aperture Radar (SAR) images, and unlike common methods of water extraction based on optical images, they are suitable for long-term monitoring because they are less affected by the weather conditions. We built four AI models such as Support Vector Machine (SVM), Random Forest (RF), Artificial Neural Network (ANN), and Automated Machine Learning (AutoML) using drone images, sentinel-1 SAR and DSM data. There are total of 22 reservoirs of less than 1 million tons for the study, including small and medium-sized reservoirs with an effective storage capacity of less than 300,000 tons. 45 images from 22 reservoirs were used for model training and verification, and the results show that the AutoML model was 0.01 to 0.03 better in the water Intersection over Union (IoU) than the other three models, with Accuracy=0.92 and mIoU=0.81 in a test. As the result, AutoML performed as well as the classical machine learning methods and it is expected that the applicability of the water-body extraction technique by AutoML to monitor reservoirs automatically.

• Journal of Korean Home Economics Education Association
• /
• v.32 no.4
• /
• pp.149-170
• /
• 2020

The purpose of this study was to develop and evaluate a Smart learning-based middle school home economics education plan to improve the online home economics education classes. The educational plan in this study was completed through the process of analysis, design, development, and evaluation. The results of this study are as follows. First, as a result of analyzing consumer life units in the middle school textbooks based on 2015-revised curriculum, Smart learning activities were presented in only two out of the 12 textbooks analyxed. Second, a Smart learning-based middle school home economics education plan was developed in this study with the following characteristics: the topics and contents are structured so that to help learners actively engage in the teaching and learning activities; the education plan to reflects various media and current issues that learners may be interested in; the lesson plans were structured with the premise of online classes; softwares that enable real-time discussion and collaboration are used; and the evaluation method are composed of online activities. Third, the expert evaluation scores for the educational plan and activity materials developed were 4.52 (5-point Likert scale), when averaged across subject, goal, content, teaching/learning activity, and evaluation, and the overall content validity index(CVI) was 0.95. The adequacy of execution, benefit, attractiveness, usefulness, and feasibility were highly with an average of 4.62. Based on the experts' comments, the education plan and activity materials were revised and completed. This study is meaningful in that it developed teaching and learning activities based on online classes after the COVID-19 outbreak, overcoming the limitations of offline classes. It has implications for face-to-face home economics classes due to COVID-19, as it suggests ways to blend online and offline teaching/learning activities depending on the situation.

• Journal of The Korean Association For Science Education
• /
• v.42 no.1
• /
• pp.61-75
• /
• 2022

Recently, lifelong learning ability was newly proposed as scientific literacy, the goal of the science curriculum. To solve various science-related problems students encounter in life, lifelong learning abilities related to science beyond school science education are required, but empirical evidence shows that students can solve problems they actually face through scientific literacy. It is not easy to find in the existing science education research. In addition, there is a lack of discussion on how to cultivate lifelong learning ability suggested in the curriculum through school science education. In this study, attention was paid to SSI education as a method for students to cultivate lifelong learning ability through school science education and to develop their ability to solve science-related problems encountered in life. In this context, statements in the existing SSI education studies were reviewed to discover discourses related to lifelong learning, and their types and characteristics were distinguished. It was possible to confirm lifelong learning and its applicability with focus on science education research through this. For the study, 18 literature materials on the subject of SSI education were selected, and the discourses related to lifelong learning in the SSI education research were discovered by examining the statements revealed in the data. As a result of the study, there are four categories of discourses related to lifelong learning: 'awareness of science,' 'connection between science and everyday life', 'promotion of participatory citizenship', and 'construction of identity'. Various SSI education studies have already had lifelong learning perception in various contexts, and the four types of discourses related to lifelong learning could be linked to the four types of learning presented in the UNESCO Lifelong Learning Report. SSI education tends to view students' life experiences as part of their learning and aims to help students develop the character and capacity to make responsible decisions on social issues related to science and put them into practice. This competency can be continuously connected to the real-life of students outside of school as a lifelong learning ability. This study requires expanding the discourse related to lifelong learning in science education and operating and managing the overall educational system to foster students' lifelong learning ability.

• Journal of Korea Water Resources Association
• /
• v.55 no.12
• /
• pp.1125-1135
• /
• 2022

Damages by heavy snow does not occur very often, but when it does, it causes damage to a wide area. To mitigate snow damage, it is necessary to know, in advance, the depth of snow that causes damage in each region. However, snow depths are measured at observatory locations, and it is difficult to understand the spatial distribution of snow depth that causes damage in a region. To understand the spatial distribution of snow depth, the point measurements are interpolated. However, estimating spatial distribution of snow depth is not easy when the number of measured snow depth is small and topographical characteristics such as altitude are not similar. To overcome this limit, satellite images such as Synthetic Aperture Radar (SAR) can be analyzed using Differential Interferometric SAR (DInSAR) method. DInSAR uses two different SAR images measured at two different times, and is generally used to track minor changes in topography. In this study, the spatial distribution of snow depth was estimated by DInSAR analysis using dual polarimetric IW mode C-band SAR data of Sentinel-1B satellite operated by the European Space Agency (ESA). In addition, snow depth was estimated using geostationary satellite Chollian-2 (GK-2A) to compare with the snow depth from DInSAR method. As a result, the accuracy of snow cover estimation in terms with grids was about 0.92% for DInSAR and about 0.71% for GK-2A, indicating high applicability of DInSAR method. Although there were cases of overestimation of the snow depth, sufficient information was provided for estimating the spatial distribution of the snow depth. And this will be helpful in understanding regional damage-causing snow depth.

• Journal of Korea Water Resources Association
• /
• v.56 no.5
• /
• pp.311-323
• /
• 2023

In order to reduce disaster damage by localized heavy rains, floods, and urban inundation, it is important to know in advance whether natural disasters occur. Currently, heavy rain watch and heavy rain warning by the criteria of the Korea Meteorological Administration are being issued in Korea. However, since this one criterion is applied to the whole country, we can not clearly recognize heavy rain damage for a specific region in advance. Therefore, in this paper, we tried to reset the current criteria for a special weather report which considers the regional characteristics and to predict the damage caused by rainfall after 1 hour. The study area was selected as Gyeonggi-province, where has more frequent heavy rain damage than other regions. Then, the rainfall inducing disaster or hazard-triggering rainfall was set by utilizing hourly rainfall and heavy rain damage data, considering the local characteristics. The heavy rain damage prediction model was developed by a decision tree model and a random forest model, which are machine learning technique and by rainfall inducing disaster and rainfall data. In addition, long short-term memory and deep neural network models were used for predicting rainfall after 1 hour. The predicted rainfall by a developed prediction model was applied to the trained classification model and we predicted whether the rain damage after 1 hour will be occurred or not and we called this as 1ST-Model. The 1ST-Model can be used for preventing and preparing heavy rain disaster and it is judged to be of great contribution in reducing damage caused by heavy rain.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.1B
• /
• pp.11-22
• /
• 2009

Long-term rainfall-runoff modeling is a key element in the Earth's hydrological cycle, and associated with many different aspects such as dam design, drought management, river management flow, reservoir management for water supply, water right permission or coordinate, water quality prediction. In this regard, hydrologists have used the hydrologic models for design criteria, water resources assessment, planning and management as a main tool. Most of rainfall-runoff studies, however, were not carefully performed in terms of considering reservoir effects. In particular, the downstream where is severely affected by reservoir was poorly dealt in modeling rainfall-runoff process. Moreover, the effects can considerably affect overall the rainfallrunoff process. An objective of this study, thus, is to evaluate the impact of reservoir operation on rainfall-runoff process. The proposed approach is applied to Anseong watershed, where is in a mixed rural/urban setting of the area and in Korea, and has been experienced by flood damage due to heavy rainfall. It has been greatly paid attention to the agricultural reservoirs in terms of flood protection in Korea. To further investigate the reservoir effects, a comprehensive assessment for the results are discussed. Results of simulations that included reservoir in the model showed the effect of storage appeared in spring and autumn when rainfall was not concentrated. In periods of heavy rainfall, however, downstream runoff increased in simulations that do not consider reservoir factor. Flow duration curve showed that changes in streamflow depending upon the presence or absence of reservoir factor were particularly noticeable in ninety-five day flow and low flow.

• 한국노년학
• /
• v.29 no.1
• /
• pp.149-175
• /
• 2009

The purpose of this research is to analyze the overall problems at the moment of October 2008, and then to find the improvements of home-help services of the Long-Term Care Insurance(LTCI), which has been revealed many problems since it was released in July 2008. The research uses the literature survey which analyzes 2nd-hand materials studied by other people already, and survey research was executed from active social workers in the area of LTCI. Based on the policy analysis framework of Gilbert and Specht, all the data are analyzed in the scopes of client·benefit(service)·finance·transferring system. This research has found the problems in each scope of home-help services of the LTCI. Firstly, the client system has some problems in mismatching between registered and service clients, estimating client number, and judging service levels. Secondly, the service system reveals deficiency in professionality of social workers, service quality lowering by loose qualification criteria on workers, non-reasonable limitation of service time available, and the same fare system applied to visiting-help service in spite of different levels. Thirdly, in financing system, clients need to pay additional money to get extra services such as meal, hair cutting, bathing etc., due to government financial support stopped, some organizations have to reduce services and replace full-time workers to part-time ones, which makes the service quality worse. Lastly, in the transferring system, the management system for service quality is not well prepared. There are too much competion because of allowing too many home-help service organizations and care worker academies. The suggestions that this research has found to improve the policy are as follows. ① It is desirable to make the registered clients the service ones as many as possible in the long term perspective. ② The LTCI organization requires more workers and higher professionality. ③ Many elderly people who are not eligible now require connection system to be more served. ④ Management system and service manual for care worker are to be developed. ⑤ Laws related to the service contents and process should be modified, the proportion of client charge needs to adjust. ⑥ Home-help service organization licensed by the LTCI needs to be financially supported publicly. ⑦ Monitoring system to home-help service organization needs to be strengthened. ⑧ Evaluation tools to home-help service organization and workers is required. ⑨ Specification to open the home-help service organization needs to be more strict.

• Journal of Korea Entertainment Industry Association
• /
• v.13 no.3
• /
• pp.181-192
• /
• 2019

The purpose of this study is to look at the fun that high school students from blind schools feel in sports programs. A questionnaire was used to collect data from 10 out of 12 blind schools nationwide, including 122 male and 102 female students. Research tools are open questionnaires and questions are as follows. - Questionnaire: "Write down three of the most interesting things about sports programs." The data analysis was done with frequency analysis and the following conclusions were drawn. First, male high school students at blind schools are able to build up their physical strength in the area of competent factors (control-self) (23, 21.5%), in the area of competent factors (7, 77.8%) and in the area of motion-related factors (competition) (24, 15.1%), and in the area of non-execution factors (26, 37.7%), Second, high school girls with visual impairments did not respond in the areas of proficiency (control-self) because of stress release (25, 26.6%), in the areas of control-tain), in the areas of movement (competition) because they were able to do various exercises (22, 15.7%), and in the areas of non-watering (environmental) (18, 37.5%). Third, in the sports program comparative analysis of high school students between genders of blind schools, boys are interested in health and physical fitness in the field of competent factors (control-self) and girls are considered to be a means of relieving stress. In the field of competent factors (control-others), boys and girls can react to a variety of sports opportunities. In the future, by studying the fun of students in the physical education program through research to find out more fun in the school physical education program, we will explore practical ways to maximize student participation and increase motivation level The educational aspect of the process, that is, the educational value provided by the physical education, should be composed of content that can change the thinking and behavior of the teacher and the student so that the program contents and operation method.

• Journal of Nutrition and Health
• /
• v.56 no.6
• /
• pp.683-701
• /
• 2023

Purpose: The purpose of the study was to analyze the status of dietary behavior and nutrition intakes according to the gender and the level of physical activity of adolescents. Methods: Data from 659 adolescents aged 13 to 18 years who participated in the Korea National Health and Nutrition Examination Survey (2017-2018) were analyzed. Collected data were analyzed using complex sampling data analysis with SPSS v. 27.0. Results: The adolescents were categorized into three groups based on their physical activity as follows: The first group with high physical activity (8.9%), a second group with normal physical activity (29.7%), and a third group without physical activity (61.4%). Boys showed significantly higher physical activity than the girls. Adolescents with high physical activity had a significantly lower body mass index than adolescents without physical activity, but their meal regularity, subjective health status, and recognition of body image were significantly higher. In terms of biochemical factors, adolescents with high physical activity had lower triglycerides and cholesterol than adolescents without physical activity, while hemoglobin and hematocrit were significantly higher. In addition, the intakes of energy, carbohydrates, proteins, fat, vitamin B₁, niacin, calcium, phosphorus, sodium, potassium, iron increased significantly as adolescents' physical activity increased. Conclusion: The physical activity of adolescents had a positive effect on dietary behavior, lifestyle, and nutritional factors. Therefore, it is necessary to increase participation in physical classes in schools and develop various programs considering the level of physical activity among adolescents.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.22 no.5
• /
• pp.53-73
• /
• 2023

Although it is mandatory to wear a seat belt that can minimize human injury when traffic accident occurs, the number of traffic accident casualties not wearing seat belts still accounts for a significant proportion.The seat belt wearing detection system for all seats is a system that identifies whether all seat passengers wear a seat belt and encourages their usage, also it can be a useful technical countermeasure. Firstly, this study established the viability of system implementation by assessing the factors influencing the severity of injuries in traffic accidents through the development of an ordered probit model. Analysis results showed that the use of seat belts has statistically significant effects on the severity of traffic accidents, reducing the probability of death or serious injury by 0.054 times in the event of a traffic accident. Secondly, a meta-analysis was conducted based on prior research related to seat belts and injuries in traffic accidents to estimate the expected reduction in accident severity upon the implementation of the system.The analysis of the effect of accident severity reduction revealed that wearing seat belts would lead to a 63.3% decrease in fatal accidents, with the front seats showing a reduction of 75.7% and the rear seats showing a reduction of 58.1% in fatal accidents. Lastly, Using the results of the meta-analysis and traffic accident statistics, the expected decrease in the number of traffic accident casualties with the implementation of the system was derived to analyze the traffic safety effects of the proposed detection system. The analysis demonstrated that with an increase in the adoption rate of the system, the number of casualties in accidents where seat belts were not worn decreased. Specifically, at a system adoption rate of 60%, it is anticipated that the number of fatalities would decrease by more than three times compared to the current scenario. Based on the analysis results, operational strategies for the system were proposed to increase seat belt usage rates and reduce accident severity.