• Korean Journal of Child Education & Care
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• v.19 no.2
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• pp.177-196
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• 2019

Objective: This study aims to analyze research trends related to software education for young children, focusing on studies published in Korea from 2016 to 2019 March. Methods: A total of 26 research publications on software education for young children, searched from Korea Citation Index and Research Information Sharing Service were identified for the analysis. The trend in these publications was classified and examined respectively by publication dates, types of publications, and the fields of study. To investigate a means of research, the analysis included key topics, types of research methods, and characteristics of the study variables. Results: The results of the analysis show that the number of publications on the topic of software education for young children has increased over the three years, of which most were published as a scholarly journal article. Among the 26 research studies analyzed, 16 (61.5%) are related to the field of early childhood education or child studies. Key topics and target subjects of the most research include the curriculum development of software education for young children or the effectiveness of software education on 4- and 5-year-old children. Most of the analyzed studies are experimental research designs or in the form of literature reviews. The most frequently studied research variable is young children's cognitive characteristics. For the studies that employ educational programs, the use of a physical computing environment is prevalent, and the most frequently used robot as a programming tool is "Albert". The duration of the program implementation varies, ranging from 5 weeks to 48 weeks. In the analyzed research studies, computational thinking is conceptualized as a problem-solving skill that can be improved by software education, and assessed by individual instruments measuring sub-factors of computational thinking. Conclusion/Implications: The present study reveals that, although the number of research publications in software education for young children has increased, the overall sufficiency of the accumulated research data and a variety of research methods are still lacking. An increased interest in software education for young children and more research activities in this area are needed to develop and implement developmentally appropriate software education programs in early childhood settings.

• Korean Journal of Heritage: History & Science
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• v.54 no.3
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• pp.228-241
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• 2021

Cremated archaeological bones provide crucial information to unravel the details of ancient cremation events and funeral culture. The research on cremated bones to date has been mainly focused on extracting archaeological information in Korea. Recently, the techniques of physical anthropology have been applied to obtain biological information and cremation temperatures for individuals. This study analyzed human remains excavated from Seoul Seokchon-dong Ancient Tombs and determined whether there were human cremations as well as the estimated cremation temperatures. There was no trace of fire in the pits where cremated bones were found; therefore, it is assumed that they were deposited with the artifacts. In this study, four samples were selected according to the surface color of the bones, and X-ray diffraction analysis (XRD) and Fourier-transformed infrared spectroscopy (FT-IR) were used for analysis. All four of the Seokchon-dong cremated bones were found, based on the crystallization index of X-ray diffraction analysis, to have experienced cremation above the temperature of 700℃. Infrared spectroscopy results indicated that the four bones from Seokchon-dong were cremated at temperatures above 700℃ and below 1,000℃. IR peaks were observed at 700℃, whereas no changes were found when bones experienced more than 1000℃. We assume that the cremated people in the Seokchon-dong Tombs were people of high-status because cremation at such a high temperature at that period required much effort. Here we present significant evidence of the cremation status and temperature of archaeological human bones on the basis of XRD and FT-IR, allowing for the restoration of the cremation events and funeral culture in archaeological sites.

• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.78-99
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• 2020

The Buddha triad and 16 Arhat statues carved on the rock surface at Seongbulsa temple is the only domestic remaining example of all 16 Arhats, so its academic value is very high. However, it is severely damaged and so required a stability evaluation through study of digital documentation and precise diagnosis for the purpose of comprehensive conservation. This process established that the Buddha statues were of similar scale, while the Arhats showed a wide variety of sizes, and the two kith and kin in the volume were larger than the Arhats. It was estimated that the statues of food for Buddha are similar to the Arhat statues, and most of the statues are well-formed. The rock used to carve the Buddha statues is banded gneiss with distinct foliation, alternating between white bands of quartz and feldspar and black bands composed of biotite. The Buddha statues have been damaged by physical weathering, discoloration, and biological contamination. In damage evaluations, joint (3.6 crack index), peeling (5.2%), exfoliation (1.7%), and falling off (0.1%) were observed on the rock surface of the Buddha statues. In particular, due to severe biological weathering, stage 9 and 10 biological coverage of the rock surface accounted for 57.5% of the total area, and stages 5 to 8 also accounted for a high share at 22.3%. The discoloration factors were shown to be dark brown and white with Fe, Ca, and S, and a large amount of C detected in the blackened contaminants, and the damage weight high in all areas. Discontinuities in different directions were identified in the rock surface. Analysis of potential rock failure types indicated that there is a possibility of plane and toppling failure, but wedge failure is unlikely to occur. The mean ultrasonic velocity of the main rock surface was 2,463m/sec, the lower part of the left side with a large number of joints was relatively low, and the highly weathered (HW) type to the completely weathered (CW) type concentrated distribution, showing weak properties. For the Buddha statues, conservation treatment is required for about 14.9% of micro cracks and 58.9% of exfoliation cracks. In addition, in order to improve the conservation environment of the Buddha statues, maintenance of drainage and ground preparations for the rock surface gradient and plants are necessary, and protection facilities should be reviewed for long-term conservation and management purposes.

• Journal of Nutrition and Health
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• v.54 no.1
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• pp.23-38
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• 2021

Purpose: This study was undertaken to evaluate the health, nutritional status and metabolic syndrome risk according to the dietary pattern of adult single-person households, using information obtained from the Korea National Health and Nutrition Examination Survey (KNHANES). Methods: Data were collected from the 2013-2016 KNHANES, of adults aged 19-64 years, belonging to single-person households. Based on cluster analysis, the dietary patterns of subjects were classified into three groups. The dietary behavior factors, health-related factors, nutritional status, and prevalence of metabolic syndrome obtained from KNHANES questionnaires were compared according to the individual dietary pattern. The nutrient intake data of the subjects were calculated using the semi-food frequency questionnaire. Moreover, blood and physical measurement data of the subjects were analyzed to obtain the prevalence of metabolic syndromes. Results: The major dietary intakes of subjects were classified as 'Rice and kimchi', 'Mixed', and 'Milk·dairy products and fruits' patterns. Characteristics of subjects based on their dietary pattern, gender, age, and education level were significantly different. The 'Milk and fruits' pattern showed low frequency of skipping breakfast and eating out, and had higher intake of dietary supplements. Frequency of alcohol intake and smoking rates were highest in the 'Mixed' pattern. Maximum nutrient intake of fat, vitamin A, riboflavin, vitamin C, niacin, calcium, phosphorus, and potassium was obtained in the 'Milk·dairy products and fruits' pattern. According to dietary patterns adjusted for age and gender, the risk of metabolic syndrome was 0.380 times lower in the 'Milk·dairy products and fruit' pattern than in the 'Rice and kimchi' pattern. However, when adjusted for other confounding factors, no significant difference was obtained between dietary patterns for metabolic syndrome risk. Conclusion: These results indicate that the health and nutritional status of a single-person household is possibly affected by the dietary intake of subjects.

• Journal of the Korean earth science society
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• v.43 no.3
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• pp.367-385
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• 2022

This study evaluates the temperature and precipitation results in East Asia simulated from the Hadley Centre Global Environmental Model version 3 regional climate model (HadGEM3-RA) developed by the UK Met Office. The HadGEM3-RA is conducted in the Coordinated Regional climate Downscaling Experiment-East Asia (CORDEX-EA) Phase II domain for 15 year (2000-2014). The spatial distribution of rainbands produced from the HadGEM3-RA by the summer monsoon is in good agreement with the Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation of water resources (APRODITE) data over the East Asia. But, precipitation amount is overestimated in Southeast Asia and underestimated over the Korean Peninsula. In particular, the simulated summer rainfall and APRODITE data show the least correlation coefficient and the maximum value of root mean square error in South Korea. Prediction of temperature in Southeast Asia shows underestimation with a maximum error during winter season, while it appears the largest underestimation in South Korea during spring season. In order to evaluate local predictability, the time series of temperature and precipitation compared to the ASOS data of the Seoul Meteorological Station is similar to the spatial average verification results in which the summer precipitation and winter temperature underestimate. Especially, the underestimation of the rainfall increases when the amounts of precipitation increase in summer. The winter temperature tends to underestimate at low temperature, while it overestimates at high temperature. The results of the extreme climate index comparison show that heat wave is overestimated and heavy rainfall is underestimated. The HadGEM3-RA simulated with a horizontal resolution of 25 km shows limitations in the prediction of mesoscale convective system and topographic precipitation. This study indicates that improvement of initial data, horizontal resolution, and physical process are necessary to improve predictability of regional climate model.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.1
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• pp.41-51
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• 1991

This study was conducted to determine the effect of 20 years long term fertilizations on the physical and chemical properties of paddy soil and the growth, yield, yield components and grain development of rice. Non-fertilized, PK, NK, NP, NPK, NPK + compost, NPK+straw and NPK+lime have been applied since 1968 after surface paddy soil was removed. NPK+compost and NPK+straw applications increased the content of organic matter, available P and CEC, and lime increased soil acidity and SiO$_2$ content. While chemical contents in non-fertilized treatment were low as compared with other treatments. Soil porosity was higher in NPK+straw (51.4%) and NPK+lime(53.1%) than in NPK application (49.8%). Soil hardness was highest in the NPK application and was lowest in the NPK + lime. Continuous application of straw with NPK markedly increased the content of aggregate with over 1mm(19.6%) as compared with NPK application (7.1%). Plant height, tiller number, root number, leaf area index and total dry weight were higher in the applications of compost, straw and lime with NPK than in any other treatments. Brown rice yield in non-fertilized, PK and NP applications was decreased 45, 55, 15 and 5% of that in NPK application, respectively, while application of compost, straw and lime with NPK increased the yield by 11, 14 and 4%, respectively, during 20 years. The number of differentiated rachis branchs in the application of compost, straw and lime was 17 to 21 and that in the other application was 13 to 15, whereas the degenerated rachis branchs was low in the application of compost, straw and lime with NPK. The applications having higher level of perfect rice grain such as non-fertilized, NPK+compost, NPK+straw and NPK+lime had high grain weight and had low level of white core rice, white belly rice. The white core and belly rice was highest in the NP application and notched belly rice kernel was markedly increased in NK and NP applications. The period of grain filling was 30 DAH at NP and NPK applications, 35 DAH at NK and NPK+lime, 40DAH at NPK+compost and NPK+ straw, and 45DAH at non-fertilized, respectively.

• 한국체육학회지인문사회과학편
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• v.51 no.3
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• pp.373-382
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• 2012

The purpose of this study is to predict VO₂max with body index and submaximal metabolic responses. The subjects are consisted of 250 male aging from 18 to 34 and we separated them into two groups randomly; 179 for a sample, 71 for a cross-validation group. They went through maximal exercise testing with Bruce protocol, and we measured the metabolic responses in the end of the first(3 minute) and second stage(6 minute). To predict VO₂max, we applied multiple regression analysis to the sample with stepwise method. Model 1's variables are weight, 6 minute HR and 6 minute VO₂(R=0.64, SEE=4.74, CV=11.7%, p<.01), and the equation is VO₂max(ml/kg/min)= 72.256-0.340(Weight)-0.220(6minHR)+0.013(6minVO₂). Model 2's variables are weight, 6 minute HR, 6 minute VO₂, and 6 minute VCO₂(R=0.67, SEE=4.59, CV=11.3%, p<.01), and the equation is VO₂max(ml/kg/min)= 68.699-0.277(Weight) -0.206(6minHR)+0.020(6minVO₂)-0.009(6minVCO₂). And the result did not show multicolinearity for both models. Model 2 demonstrated more correlation compared to Model 1. However, when we conducted cross-validation of those models with 71 men, measured VO₂max and estimated VO₂ Max had statistical significance with correlation (R=0.53, 0.56, P<.01). Although both models are functional with validity considering their simplicity and utility, Model 2 has more accuracy.

• Journal of Internet of Things and Convergence
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• v.9 no.2
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• pp.19-31
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• 2023

The importance of barrier free is being highlighted worldwide. This study attempted to identify barrier-free research trends using text mining. Through this, it was intended to help with research and policies to create a barrier free environment. The analysis data is 227 papers published in domestic academic journals from 1996 when barrier free research began to 2022. The researcher converted the title, keywords, and abstract of an academic thesis into text, and then analyzed the pattern of the thesis and the meaning of the data. The summary of the research results is as follows. First, barrier-free research began to increase after 2009, with an annual average of 17.1 papers being published. This is related to the implementation guidelines for the barrier-free certification system that took effect on July 15, 2008. Second, results of barrier-free text mining i) As a result of word frequency analysis of top keywords, important keywords such as barrier free, disabled, design, universal design, access, elderly, certification, improvement, evaluation, and space, facility, and environment were searched. ii) As a result of TD-IDF analysis, the main keywords were universal design, design, certification, house, access, elderly, installation, disabled, park, evaluation, architecture, and space. iii) As a result of N-Ggam analysis, barrier free+certification, barrier free+design, barrier free+barrier free, elderly+disabled, disabled+elderly, disabled+convenience facilities, the disabled+the elderly, society+the elderly, convenience facilities+installation, certification+evaluation index, physical+environment, life+quality, etc. appeared in a related language. Third, as a result of the CONCOR analysis, cluster 1 was barrier-free issues and challenges, cluster 2 was universal design and space utilization, cluster 3 was Improving Accessibility for the Disabled, and cluster 4 was barrier free certification and evaluation. Based on the analysis results, this study presented policy implications for vitalizing barrier-free research and establishing a desirable barrier free environment.

• Journal of the Korean Geotechnical Society
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• v.26 no.12
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• pp.19-30
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• 2010

Bentonite-based grout has been widely used to seal a borehole constructed for a closed-loop vertical ground heat exchanger in a geothermal heat pump system (GHP) because of its high swelling potential and low hydraulic conductivity. Three types of bentonites were compared one another in terms of viscosity and thermal conductivity in this paper. The viscosity and thermal conductivity of the grouts with bentonite contents of 5%, 10%, 15%, 20% and 25% by weight were examined to take into account a variable water content of bentonite grout depending on field conditions. To evaluate the effect of salinity (i.e., concentration of NaCl : 0.1M, 0.25M, and 0.5M) on swelling potential of the bentonite-based grouts, a series of volume reduction tests were performed. In addition, if the viscosity of bentonite-water mixture is relatively low, particle segregation can occur. To examine the segregation phenomenon, the degree of segregation has been evaluated for the bentonite grouts especially in case of relatively low viscosity. From the experimental results, it is found that (1) the viscosity of the bentonite mixture increased with time and/or with increasing the mixing ratio. However, the thermal conductivity of the bentonite mixture did not increase with time but increased with increasing the mixing ratio; (2) If bentonite grout has a relatively high swelling index, the volume reduction ratio in the saline condition will be low; (3) The additive, such as a silica sand, can settle down on the bottom of the borehole if the bentonite has a very low viscosity. Consequently, the thermal conductivity of the upper portion of the ground heat exchanger will be much smaller than that of the lower portion.

• Korean Journal of Ecology and Environment
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• v.55 no.1
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• pp.35-48
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• 2022

Fish assemblage of total 325 of Korean peninsula estuaries were surveyed to analyze the characteristics of community structure and diversity by sea areas for three years from 2016 to 2018. The scale (stream width) of Korean estuaries were various (14~3,356 m), and 68.9% of all estuaries showed salinity of less than 2 psu. Total 149 species classified into 52 families of fish were identified, and the dominant and sub-dominant species were Tribolodon hakonensis (relative abundance, RA, 12.5%) and Mugil cephalus (RA, 9.5%), respectively. The estuary of the Korean Peninsula had different physical and chemical habitat environments depending on the sea area, and accordingly, fish community structure also showed statistically significant differences (PERMANOVA, Pseudo-F=26.69, P=0.001). In addition, the NMDS (nonmetric multidimensional scaling) results showed the patterns that indicating fish community difference by sea areas, even though low community similarity within sea area (SIMPER, 21.79~26.39%). The estuaries of east sea areas were distinguished from the others in the aspects of which, the higher importance of migratory fishes and endangered species, and that of brackish species were characterized at south sea estuaries. However, the estuaries of west sea showed higher importance of species that have a relation with freshwater (primary freshwater species, exotic species), which is the result that associating with the lower salinity of west sea estuaries because of the high ratio of closed estuaries(78.2%). The SIMPER analysis, scoring the contribution rates of species to community similarity, also showed results corresponding to the tendency of different fish community structures according to each sea area. So far, In Korea, most studies on fish communities in estuaries have been conducted in a single estuary unit, which made it difficult to understand the characteristics of estuaries at the national level, which are prerequisite for policy establishment. In present study, we are providing fish community structure characteristics of Korean estuaries in a national scale, including diversity index, habitat salinity ranges of major species, distribution of migratory species. We are expecting that our results could be utilized as baseline information for establishing management policies or further study of Korean estuaries.