• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.5
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• pp.953-964
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• 2023

Climate change is undeniably the most urgent challenge that humanity faces today. Despite this, the level of public awareness and understanding of climate change remains insufficient, indicating a need for more proactive education and the development of supportive content. In particular, it is crucial to intensify climate change education during elementary and secondary schooling when values and ethical consciousness begin to form. However, there is a significant lack of age-appropriate, experiential educational content. To address this, our study has developed an innovative 3D simulator, enabling learners to indirectly experience the effects of climate change, specifically sea-level rise. This simulator considers not only sea-level rise caused by climate change but also storm surges, which is a design based on the analysis of long-term wave observation big data. To make the simulator accessible and engaging for students, we utilized the 'Unity' game engine. We further propose using this simulator as a part of a comprehensive educational program on climate change.

• Journal of Intelligence and Information Systems
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• v.20 no.3
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• pp.1-18
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• 2014

Over the past years RFID/SN has been an elementary technology in a diversity of applications for the ubiquitous environments, especially for Internet of Things. However, one of obstacles for widespread deployment of RFID technology is the inherent unreliability of the RFID data streams by tag readers. In particular, the problem of false readings such as lost readings and mistaken readings needs to be treated by RFID middleware systems because false readings ultimately degrade the quality of application services due to the dirty data delivered by middleware systems. As a result, for the higher quality of services, an RFID middleware system is responsible for intelligently dealing with false readings for the delivery of clean data to the applications in accordance with the tag reading environment. One of popular techniques used to compensate false readings is a sliding window filter. In a sliding window scheme, it is evident that determining optimal window size intelligently is a nontrivial important task in RFID middleware systems in order to reduce false readings, especially in mobile environments. In this paper, for the purpose of reducing false readings by intelligent window adaption, we propose a new adaptive RFID data cleaning scheme based on window sliding for a single tag. Unlike previous works based on a binomial sampling model, we introduce the weight averaging. Our insight starts from the need to differentiate the past readings and the current readings, since the more recent readings may indicate the more accurate tag transitions. Owing to weight averaging, our scheme is expected to dynamically adapt the window size in an efficient manner even for non-homogeneous reading patterns in mobile environments. In addition, we analyze reading patterns in the window and effects of decreased window so that a more accurate and efficient decision on window adaption can be made. With our scheme, we can expect to obtain the ultimate goal that RFID middleware systems can provide applications with more clean data so that they can ensure high quality of intended services.

• Journal of Science Education
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• v.45 no.3
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• pp.292-303
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• 2021

This study identifies the terms frequently used together with energy in online science news articles and topics of the news reports to find out how the term energy is used in everyday life and to draw implications for science curriculum and instruction about energy. A total of 2,171 online news articles in science category published by 11 major newspaper companies in Korea for one year from March 1, 2018 were selected by using energy as a search term. As a result of natural language processing, a total of 51,224 sentences consisting of 507,901 words were compiled for analysis. Using the R program, term frequency analysis, semantic network analysis, and structural topic modeling were performed. The results show that the terms with exceptionally high frequencies were technology, research, and development, which reflected the characteristics of news articles that report new findings. On the other hand, terms used more than once per two articles were industry-related terms (industry, product, system, production, market) and terms that were sufficiently expected as energy-related terms such as 'electricity' and 'environment.' Meanwhile, 'sun', 'heat', 'temperature', and 'power generation', which are frequently used in energy-related science classes, also appeared as terms belonging to the highest frequency. From a network analysis, two clusters were found including terms related to industry and technology and terms related to basic science and research. From the analysis of terms paired with energy, it was also found that terms related to the use of energy such as 'energy efficiency,' 'energy saving,' and 'energy consumption' were the most frequently used. Out of 16 topics found, four contexts of energy were drawn including 'high-tech industry,' 'industry,' 'basic science,' and 'environment and health.' The results suggest that the introduction of the concept of energy degradation as a starting point for energy classes can be effective. It also shows the need to introduce high-tech industries or the context of environment and health into energy learning.

• Journal of Mushroom
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• v.16 no.2
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• pp.111-117
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• 2018

This study was conducted to compare the composition and antioxidant activity of 1- and 2-year-old Poria cocos Wolf cultivated at a mortuary and cemetery. An elemental analyzer test showed oxygen, carbon, hydrogen, nitrogen, and sulfur to be present at concentrations of 45~46%, 39~41%, 6.06~6.1%, 0.21~0.22%, and 0%, respectively. No differences in composition were observed among samples. Eleven minerals (S, Ca, Mg, P, As, Se, Cu, Fe, Pb, Zn, and Cd) found in P. cocos cultivated at the mortuary and cemetery were analyzed by inductively coupled plasma mass spectrometry (ICP). The levels of S, Fe, Mg, and Zn in P. cocos were higher in cemetery-cultivated samples than in mortuary-cultivated samples. A 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay for antioxidant activity revealed half-maximal inhibitory concentration ($IC_{50}$)values of P. cocos to be 8.601 mg/mL (mortuary, 1 year old), 12.85 mg/mL (cemetery, 1 year old), 1.23 mg/mL (mortuary, 2 years old), and 1.18 mg/mL (landfill, 1 year old). A 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay revealed $IC_{50}$ values of 15.85 mg/mL (mortuary, 1 year old),14.59 mg/mL(cemetery, 1 year old), 3.9 mg/mL (mortuary, 2 years old), and 14.92 mg/mL (cemetery, 1 year old). The results showed a concentration-dependent effect. Two-year-old mortuary-cultivated P. cocos had the highest antioxidant activity among samples. Ultrastructure analysis with a field emission scanning electron microscope (FE-SEM) showed no obvious differences among samples.

• Journal of environmental and Sanitary engineering
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• v.20 no.1 s.55
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• pp.64-75
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• 2005

The total production of food waste was about 11,398ton/day('03) in Korea. Also, food waste was treated by landfill, incineration, reuse and anaerobic digestion. The method of food waste treatment depended primarily on landfill. However, the method of landfill causing social problems was prevented to treat food waste in the first of January 2005.12) Thus, anaerobic digestion is an important method to treat food waste because of possibility of energy recovery as methane gas. In this study, the possibility of food waste treatment containing high organic material and low pH in the one stage anaerobic reactor to save cost and time and energy recovery using $CH_{4}$ gas by the hybrid anaerobic reactor (HAR) was measured. The HAR was designed by combing the merits of the anaerobic filter (AF) to minimize the microorganism shock when food waste of very low pH was injected and up-flow anaerobic sludge blanket (UASB) to prevent from plugging and channeling phenomena by large suspended solids when semi solids were injected. Granule was packed in the section of HAR. The purpose of the BMP experiment was to measure the amount of methane generated when organic material was resolved under anaerobic conditions, to grasp bio resolution of organic material. Total accumulated methane production per VS amount was $0.471(m^{3}/\cal{kg}\;VS)$. So, the value was about $81.2\%$ of theoretical methane production which was $0.58(m^{3}/\cal{kg}\;VS)$ by elementary analysis and organic matter removal velocity (K) was $0.18(d^{-1})$. From these results, food waste was treated by anaerobic treatment. From this study, $CH_{4}$ generation from food waste (11,398 ton/day) could be estimated. By using an energy conversion factor of Braun's study, $5.97KWh/m^{3}\;CH4,\;60\%\;of\;CH_{4}$ gas generation, the amount of total energy producing food waste is to 6,727MWh/day. It could be confirmed that energy recovery using $CH_{4}$ gas was possible. Above these results, food waste containing organic matters of high concentration could be treated in HRT 30 days under an anaerobic condition, using the hybrid anaerobic reactor and reuse of $CH_{4}$ gas was possible.

• Journal of Nutrition and Health
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• v.53 no.5
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• pp.503-517
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• 2020

Purpose: This study examined the yearly trend of milk consumption and the nutritional status of subjects aged 6-18 years using the 2007-2015 Korea National Health and Nutrition Examination Survey data. Methods: Milk and dairy products were classified into plain milk, flavored milk, and dairy products (ice cream, milkshakes, cheese, and yogurt, etc.). This study compared the milk and dairy products intakes, some nutrients intakes and percent of dietary reference intakes for Koreans in the milk intake and non-milk intake groups. Results: Plain milk intake decreased with year (male, p = 0.0199; female, p < 0.0001; elementary school, p = 0.0013; high school, p = 0.0061), whereas flavored milk and dairy products intake in these subjects increased with year. In all subjects, 49.9% of subjects did not drink milk at all. The intakes of energy, protein, fat, calcium, phosphorus, and riboflavin in the milk intake group were significantly higher than those in the non-milk intake group, even after adjusting for covariates (p < 0.05). The odds ratio of the prevalence of nutritional deficiency in the non-milk intake group was 3.2 times higher than that of the milk intake group (p < 0.001), even after adjusting for covariates. The odds ratio for the prevalence of excess intake of the energy/fat was not significant with milk intake. Conclusion: The prevalence of milk intake decreased every year in the subjects. Calcium deficiency and nutritional deficiency were very high in the non-milk intake group. Efforts should be made to improve the calcium status in children and adolescents by strengthening nutrition education about the importance of milk intake.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.2
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• pp.1-20
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• 2020

The purpose of this study was to analyze the distribution characteristics of spatial and temporal PM_2.5 in urban areas of Changwon-si, and to identify the causes of PM_2.5 by comparing the characteristics of land-use, and to suggest the direction of reduction measures. As the basic data, the every hour average from September 2017 to August 2018 of Airpro data, which has measurement points in kindergartens, elementary schools, and some middle and high schools in Changwon-si was used. Also, by using IDW method among spatial interpolation methods of GIS, monthly and time-slot distribution maps were constructed, and based on this, spatial and temporal PM_2.5 distribution characteristics were confirmed. First, to verify the accuracy of the Airpro data, the correlation with AirKorea data managed by the Ministry of Environment was confirmed. As a result of the analysis, R² was 0.75~0.86, showing a very high correlation and the data was judged that it was suitable for the study. In the monthly analysis, January was the highest year, and August was the lowest. As a result of analysis by time-slot, The clock-in time at 06-09 was the highest, and the activity time at 09-18 was the lowest. By administrative district, Sangnam-dong, Happo-dong, and Myeonggok-dong were the most severe regions of PM_2.5 and Hoeseong-dong was the lowest. As a result of analyzing the land-use characteristics by administrative area, it was confirmed that the ratio of traffic area and commercial area is high in the serious area of PM_2.5. In conclusion, the results of this study will be used as basic data to grasp the characteristics of PM_2.5 distribution in Changwon-si. Also, it is thought that the severe regions and the direction of establishing reduction measures derived from this study can be used to prepare more effective policies than before.

• Journal of The Korean Association For Science Education
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• v.32 no.4
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• pp.775-788
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• 2012

This study was done at a scientific camp sponsored by Nara Women's University Secondary School, Japan. In this school, $10^{th}$ grade students from 4 East Asian countries: Korea, Japan, Taiwan, and Singapore, participated. We made a research on students' perceptions about nuclear energy. Sample populations include 77 students in total, with 12 Korean, 46 Japanese, 9 Taiwanese and 10 Singaporean students. Overall perceptions comparison about nuclear energy shows average values from the order of highest Korea, Taiwan, Singapore, and to lowest, Japan. We implemented a T-test to identify perception differences about nuclear energy, with one group that include 3 countries (Korea, Taiwan and Singapore) and another group that includes all the Japanese students. T-test results of perceptions about nuclear energy shows students from the 3 countries of Korea, Taiwan and Singapore having higher average than Japanese students. (p<.05). Korean average scores regarding overall perceptions about nuclear energy show as the highest in all 4 East Asian countries and also highest in all subcategories. On the contrary in Japan, they have lower and negative perceptions of nuclear energy. In spite of these facts, perceptions of Japanese students about nuclear energy seem lowest and negative mainly because of the recent Fukushima nuclear power plant disaster, caused by the tsunami and its subsequent damages and fears of radiation leaks, etc. This shows that negative information about future disasters and its resulting damages like the Chernobyl nuclear accident could influence more on people's risk perception than general information like nuclear energy-related technologies or the news that the plant is operating normally, etc. Even if the possibility of this kind of accident is very low, just one accident could bring abnormal risks to technology itself. This strong signal makes negative image and strengthens its perceptions to the people. This could bring a stigma about nuclear energy. This study shows that Government's policy about the highest priority for nuclear energy safety is most important. As long as such perception and decision are fixed, we found that it might not be easy to get changed again because they were already fortified and maintained.

• Journal of radiological science and technology
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• v.28 no.4
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• pp.327-332
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• 2005

The purpose of this Study was to investigate the prevalence rate of idiopathic scoliosis to the students from the elementary to the university in S city of Chung-Nam using 100 mm Mirror Camera radiation indirect examination units, with on age range of between eight and thirteen (1.526 subjects), fourteen and sixteen (462 subjects), seventeen and eighteen (291 subjects), nineteen and twenty four(508 subjects) and total of 2,787 participants with the 590 male subjects and 2,197 female subjects. The results of this study can be summarized and compared the primary examination with the secondary test of greater than $10^{\circ}$of Cobb's Angle were obtained as follows; 1. Indirect Examination were conducted to find idiopathic scoliosis amomg total 2.787 subjects, 257 subjects (9.2%) who showed positive sign greater than $10^{\circ}$in the Cobb's Angle ; below age of thirteen (132 subjects), between fourteen and sixteen (52 subjects), seventeen and eighteen (35 subjects), nineteen and twenty four (38 subjects). The $x^2-test$ analysis of Indirect Examination showed no statistical significant difference association between the age range and $10^{\circ}$Cobb's Angle of spinal curve(P>0.059). 2. The numbers of idiopathic scoliosis of greater than $10^{\circ}$Cobb's Angle of spinal curve in the primary examination were observed in 147 subjects (57.2%) at the Thoracolumbar region, 81subjects (31.5%) at the Thoracic region, 20 subjects (7.8%) at the Cervicothoracic region, 7 subjects (2.7%) at the Lumbar region, 2 subjects (0.8%) at the Cervical region. So, the large numbers were Thoracolumbar region, 183 participants (71.2%) showed the right side curve of scoliosis and 74 participant (28.8%) showed the left side curve of scoliosis. 3. The main region of the pain in one's own self more than $10^{\circ}$ Cobb's angle of spinal curve were no pain 219 subjects (85.2%), 18 subjects (7.0%) at the Lumbar region, 9 subjects (3.5%) at the Cervical region, 7 subjects (2.7%) at the Thoracic region, 2 subjects (0.7%) at the shoulder girdle region, 1 subjects (0.39%) at the pelvis and whole body region. There was statistical significant difference association between the Cobb's Angle of spinal curve and the main pain region of one's (P<0.006). This study may be significant to an early stage investigate of the prevalence rate of idiopathic scoliosis in the juveniles using 100 mm Mirror Camera radiation indirect examination units. The results of this study help that the students in a stage on growth the basis of data early discovery and therapy of idiopathic scoliosis.