• Journal of the Korean Society of Radiology
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• v.16 no.6
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• pp.779-786
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• 2022

This study is designed to examine the effects of Dioscorea Quinqueloba extract as a natural radiation protection agent on the prostate and heart of male rats. Dioscorea Quinqueloba extract is well known to prevent the male-specific disease and heart disease. In this study, the Gamma-ray 10 Gy was irradiated in whole body of male rat to identify radioprotective effect by Dioscorea Quinqueloba extract. After irradiation, tissue change, SOD (Superoxide Dismutase) activity changes and hematological changes were observed. DQ+IR group showed higher lymphocyte, white blood cell, platelet levels than the IR group. In the NC and DQ groups, the number of prostate gland cells and the gap between cells were relatively narrow. But in the IR group, the cells died significantly and the gap widened. In the DQ+IR group, the gap between cells increased similarly to the IR group, but the number of dead cells was noticeably smaller. In the NC and DQ groups, the cardiovascular and myocardium are clearly separated, and cell nuclei are in good condition. But in the IR group, the cardiovascular and myocardium boundaries were disrupted, and the number of dead cell nuclei was high. In the DQ+IR group, although the boundaries were widened, but not disrupted and the number of dead cell nuclei was high. Therefore, Dioscorea Quinqueloba extract is judged to have radioprotective properties for the prostate and cardiovascular.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.246-254
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• 2022

Domestic facility agriculture grows rapidly, such as modernization and large-scale. And the production scale increases significantly compared to the area, accounting for about 60% of the total agricultural production. Greenhouses require energy input to create an appropriate environment for stable mass production throughout the year, but the energy load per unit area is large because of low insulation properties. Through the rooftop greenhouse, one of the types of urban agriculture, energy that is not discarded or utilized in the building can be used in the rooftop greenhouse. And the cooling and heating load of the building can be reduced through optimal greenhouse operation. Dynamic energy analysis for various environmental conditions should be preceded for efficient operation of rooftop greenhouses, and about 40% of the solar energy introduced in the greenhouse is energy exchange for crops, so it should be considered essential. A major analysis is needed for each sensible heat and latent heat load by leaf surface temperature and evapotranspiration, dominant in energy flow. Therefore, an experiment was conducted in a rooftop greenhouse located at the Korea Institute of Machinery and Materials to analyze the energy exchange according to the growth stage of crops. A micro-meteorological and nutrient solution environment and growth survey were conducted around the crops. Finally, a regression model of leaf temperature and evapotranspiration according to the growth stage of leafy vegetables was developed, and using this, the dynamic energy model of the rooftop greenhouse considering heat transfer between crops and the surrounding air can be analyzed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.4
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• pp.199-210
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• 2022

This study aimed to develop a cropping system to use limited crop-land with optimum efficiency, while considering management from farmers. To establish the cropping system involving a two-year rotation of three crops, three types of cropping system were evaluated in Suwon (Seogcheon series) and Anseong (Geumcheon series) in the middle plain area using six crops from 2018 to 2019: maize-perilla-onion, potato-sesame-garlic, and maize-sesame-onion. The crop productivity and income of the cropping systems involving food-, oilseed-, and horticultural crops were analyzed, and the optimal cropping system was reviewed. The total yield of each crop was as follows: maize 1,281 kg, potato 4,837 kg, perilla 125 kg, sesame 120 kg, onion 6,503 kg, and garlic 1,027 kg per 10a. However, in terms of gross profit, the potato was more than 3.8 times more profitable than corn, sesame was 1.8 times more profitable than perilla, and garlic was more than 2.8 times more profitable than onions. As a result, in terms of net income, the potato-sesame-garlic cropping system produced the highest income per unit area. Sesame seedlings were planted after the potato harvest, thereby solving the problem of competition between the first and last crops. Overall, this study confirmed that the potato-sesame-garlic cropping system, a two-year rotation of three crops, contributed to the improvement of upland crop productivity and farmers' income and was an overall effective cropping system.

• Journal of Korean Home Economics Education Association
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• v.34 no.4
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• pp.19-41
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• 2022

This study aims to confirm the effect of the 'Meal and Cooking for Single-Person Households' education program on improving the dietary management competency of high school students. In order to achieve this research purpose, 'Meal and Cooking for Single-Person Households' education program was developed, implemented, and evaluated based on the ADDIE instructional design model. The results of this study are as follows. First, an analysis was conducted on literature and prior research related to the dietary life of single-person households and dietary education programs of the home economics subject. Based on this, the theoretical background for the 'Meal and Cooking for Single-Person Households' education program was established. Then, teaching-learning process plan and student workbooks for a total of 16 unit classes were developed. The expert validity of the program was verified by 6 experts who are current high school home economics teachers and have experience in conducting research related to dietary education programs. As a result, the average of all items was 4.89 (out of 5 points) and the CVI was 0.98, securing very excellent content validity. Second, the researcher directly implemented 'Meal and Cooking for Single-Person Households' education program for 100 students in Y high school located in Sejong city. Considering the school's situation, the 16th session of teaching-learning process plan was shortened to 6th sessions while all the core topics. A survey was conducted on students who participated in the program and the pre- and post- results were analyzed. As a result of the survey analysis, the 'Meal and Cooking for Single-Person Households' education program had a positive effect on improving the dietary management competency of high school students. This study is meaningful in that it has implications for the development of a new subject in home economics in preparation for the high school credit system and improving dietary management competency in accordance with social changes in the era of single-person households, and the 'Meal and Cooking for Single-Person Households' education program developed in this study can be used as a mini-subject in the 2022 revised curriculum.

• Korean Journal of Environment and Ecology
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• v.36 no.6
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• pp.639-650
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• 2022

Abeliophyllum distichum Nakai, a rare plant with distylous characteristics, is native to certain parts of the Korean Peninsula. It is registered on the IUCN Red List of Threatened Species as a globally endangered plant. This study was conducted to establish an appropriate local conservation management plan suitable for future A. distichum populations by comparing and analyzing the flowering characteristics and population size according to distyly based on the results of quantitative surveys in 14 regions, including 8 areas with native populations of A. distichum and 6 natural monument populations. The number of individuals appearing in each population group was surveyed, and the flowering individuals were identified by style as being either pin or thrum flower types as they were being examined and recorded on the site. In total, 13,130 individuals of A. distichum (7,003 flowering and 6,127 non-flowering individuals) were recorded, but the balance of the number of pin- and thrum-flowered individuals in each population was not significant (p<0.05), indicating an imbalanced state. In particular, the Yeongdong (YD) population was very disproportionate compared to other populations, suggesting that its genetic diversity was low and the possibility of inbreeding was high. The average flowering and fruiting rates by management unit were much higher in the natural monument populations (89.2% and 55.3%, respectively) than in the natural habitat populations (39.0% and 8.5%, respectively). It may be due to a difference in reproductive growth resulting from light inflow into the forest caused by the upper crown closure. The area of occupation (AOO) of A. distichum on the Korean Peninsula covered an area of 23,224.5 m². Although the natural monument population was smaller than the natural habitat population, its density was higher, likely as a result of the periodic management of natural monument populations, where the installation of protective facilities in certain areas restricts population spread. Conservation of A. distichum populations requires removing the natural monument populations suspected of anthropogenic and genetic disturbances and expanding the conservation priority population by designating new protected areas. Although the habitats of natural monument populations are managed by the Cultural Heritage Administration and local governments, there are no agencies that are responsible for managing natural habitat populations. Therefore, institutional improvement in the overall management of A. distichum should be prioritized.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.125-135
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• 2022

In this study, growth changes of the diameter at breast height (DBH), height, basal area, volume, and biomass of Korean white pine (Pinus koraiensis Siebold & Zucc.) on a plantation were examined via long-term monitoring. In addition, this study was performed to provide the basic data for timber production in line with DBH class by comparing the growth of the relative DBH size. Growth characteristics according to DBH class were analyzed by categorizing trees into five classes based on sorted DBH rankings: class I (1%-20%; upper 20%), class II (21%-40%), class III (41%-60%), class IV (61%-80%), class V (81%-100%; lower 20%). A total class (0%-100%) was also used. Total increment and mean annual increment (MAI) were calculated using data from nine measurements taken over 39 years. Tree characteristics based on average values and stand characteristics based on unit area per hectare were examined. According to the total increments of variables, the differences in DBH, basal area, volume, and biomass among classes I-V increased over time, whereas the height difference did not continually increase. According to MAI, the maximum DBH value was 0.92 cm·yr^-1 at age 23 in class I, whereas the maximum value in all trees was 0.69 cm·yr^-1 at age 17. The maximum value of height MAI for class I was 0.52 m·yr^-1 at age 23, whereas that for all trees was 0.49 m·yr^-1 at age 20. In terms of basal area, volume, and biomass growth at tree-and stand-level, the maximum MAI of class I and all trees was not observed during the measurement period. Therefore, additional long-term monitoring data are required to determine the maximum MAI of the variables.

• (The) Research of the performance art and culture
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• no.39
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• pp.549-580
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• 2019

There are many festivals in the region that mainly use traditional performing arts. Traditional performing arts has a story that incorporates the history of the area, and it is easy to build a brand that can be distinguished from other areas through traditional performing arts, so it has conditions that are easy to grow in the local festival it can. In this paper, I researched the relationship between the significance and regionality of regional performing arts, referring to the case where traditional performing arts, which is a joint cultural heritage of East Asia, are transmitted as a festival. The performance art with strong locality has grown into a local festival, and the Kanto Festival (竿燈) held in Akita prefecture in northeastern Japan was selected as a representative example of that area. Along with the Aomori Nebuta Festival and the Sendai Tanabata Festival, the Kanto Festival is called the 3 major festivals in the northeastern part of Japan. It was designated as an important intangible folk cultural property in 1980 and became more famous. It visited Seoul several times after the 2005 Japan-Korea Exchange Festival event. It is widely known as a regional festival that represents Japan. The Kanto Festival, which was a participatory event on a village basis, has faced problems such as the migration and aging of young people since the 1970s. In order to solve this, they led the participation of schools, educational institutions, and various groups beyond the village unit and persuaded the participation to the local companies. They have been steadily promoting free lectures on technical skills and school visit events that induce children's interest. As a result, the number of moths mobilized in the current festival has reached 250, and the Kanto tournament also shows great popularity every year.

• Korean Journal of Poultry Science
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• v.50 no.3
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• pp.125-132
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• 2023

This study was conducted to investigate the effect of moisture absorbent (MA) application timing for litter management on broiler performance, blood cell characteristics, litter moisture content, incidence of footpad dermatitis (FPD), and economics analysis. Treatment include untreated control (NC), 3-week-old litter treatment (PC), 0-week-old (W1), 0 and 3-week-old (W2), 3-week-old (W3) application of moisture absorbent. Six hundred eighty broilers (1-day-old, 42.0±0.24 g) were divided into 5 treatments (4 replications per treatment, 34 birds per replication) and raised for 5 weeks in a floor (2 m² per pen). There was no significant difference among treatments in performance, blood cell characteristics, and H/L ratio according to the application period of litter and moisture absorbent. The litter moisture content and the FPD score were significantly decreased in the litter and moisture absorbent treatments at the age of 5 weeks (P<0.05). The FPD score of broilers was lowest in PC treatment compared to NC treatment (P<0.05). The incidence of FPD was lower in PC and W3 treatments compared to other treatments, and that was the highest in NC treatment. As a result of analyzing the economic feasibility, the highest expenditure occurred in PC treatment, and the lowest expenditure occurred in W3 treatment. Income was the highest in W3 treatment, and lowest in NC treatment. The profit was 185,859 won (1,367 won/unit), the highest in the W3 treatment. In conclusion, when MA was applied to the litter of broiler house at the age of 3 weeks, the litter moisture content and FPD were improved.

• Land and Housing Review
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• v.14 no.4
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• pp.17-37
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• 2023

The rental housing market in South Korea, specifically monthly rent with deposit, has been expanding over the last three decades (8.2% in 1990 to 21.0% in 2020), partly replacing the traditional Jeonse market. The distribution of rent has changed due to public rental subsidies and the emergence of luxury rental housing, while the distribution of rental household income has been polarized because of the emergence of rich renters. This study attempts to measure the structural changes in the rental market by developing a new indicator of income-rent mismatch. Using the seven series of the Korea Housing Survey, this study analyzed the changes in rent (reflecting the conversion rate) and income levels of rental households in 2006 (base year) and 10-15 years later (the analysis year) at the national level and at the spatial unit of 16 metropolitan cities and provinces (excluding Sejong), respectively, by dividing them into quartile data. The result reveals that rental housing was undersupplied in middle- and high-income rental housing due to the decline in the highest quartile (25%→18%) and the third quartile groups (25%→20%), while the supply of public rental housing expanded for the second quartile (25%→28%) and the lowest quartile (25%→35) groups. On the demand side, the highest income quartile shrank (25%→21%), while the lowest income quartile grew (25%→31%). Comparing the 16 metropolitan cities and provinces, there were significant regional differences in the direction and intensity of changes in rent and renter household income. In particular, the rental market in Seoul was characterized by supply polarization, which led to an imbalance in the income distribution of rental households. The structural changes in the apartment rental market were different from those in the non-apartment rental market. The findings of this study can be used as a basis for future regional rental housing markets. The findings can support securing affordable rental housing stock for each income quartile group on monthly rent and developing housing stability measures for a balance between income and rent distribution in each region.

• Journal of The Korean Association For Science Education
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• v.44 no.4
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• pp.325-341
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• 2024

This study examined how specific aspects of epistemic cognition are developed in elementary students during modeling activities, using the Apt-AIR framework. The study focused on a class unit titled 'Shall We Find Out What the Landscape of a Riverside Looks Like?' which is part of the land chapter in the third-grade Korean elementary science curriculum. Ambitious Science Teaching (AST) was applied as a teaching strategy to enhance students' model construction. Seven science classes were conducted in line with the core practices of AST, with 29 elementary school students participating in the study. The classes were organized into four stages: initial model composition, inquiry activity, group model composition-sharing, and final model construction. The class activities at each stage were analyzed using both the AIR model, i.e., epistemic aim and value (A), epistemic ideals (I), and reliable epistemic processes (R), and the multi-faceted framework for epistemic thinking from the Apt-AIR framework. The results of the study revealed that in science classes emphasizing modeling activities based on the core practices of AST, the elementary students progressively developed more sophisticated explanatory models that included causal relationships explaining the topographic differences between the upstream and downstream sections of a river. This result was due to their engagement in constructing initial models to describe phenomena, supplementing the initial models using data collected in the model experiment, and participating in discussions to share and evaluate group models. Additionally, from the perspective of the Apt-AIR framework, the aspects of epistemic cognition demonstrated by the elementary students in their modeling activities were appropriate for engaging with cognitive processes related to epistemic aims and values, epistemic ideals, and reliable processes. The other four aspects of the Apt-AIR framework, however, were not performed as effectively. In particular, the application of reliable epistemic processes for knowledge construction required more improvement.