• Korean Journal of Mineralogy and Petrology
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• v.34 no.4
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• pp.241-253
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• 2021

Manganese nodules have been found in the shallow water depth of the Arctic Ocean as well as in the abyssal plains of the Pacific and Indian Oceans, but detailed study for them were rarely investigated. Manganese nodules, collected from the East Siberian Sea through the Arctic Expedition using Araon ice braking vessel, have a high potential for Mn mineral resources because they have high Mn content with high Mn/Fe ratio. This study investigated the external form, size and weight, internal texture for the non-spherical manganese nodule, which has about 7 % of total nodule from the East Siberian Sea. This study also researched the relative Mn-oxide mineral composition using the peak area ratio of X-ray diffraction pattern and their chemical composition. All data obtained from non-spherical nodules were compared with the spherical ones. Ellipsoidal, platy and irregular types are common among 5 groups of non-spherical manganese nodule based on the external form, and major axis and weight have positive relationship. All non-spherical manganese nodules have core mainly composed of mud sediments. The average Mn oxide mineral contents in nodules are birnessite, buserite and todorokite in descending order. Although mineral composition does not show any correlation with the external form, kind of core or internal structure, todorokite and buserite contents tend to increase and birnessite content decrease from the surface to the core in the nodule. Non-spherical manganese nodules have higher Mn content and Mn/Fe ratio than those from the shallow water depth of the Arctic Sea and even in the deep-sea of the Pacific and Indian Ocean. Although non-spherical nodule is larger and heavier, and has lower Mn content and Mn/Fe ratio than spherical nodule, there are not any differences in mineral composition and internal structure between them. Almost all manganese nodules collected from the East Siberian Sea are attributed to diagenetic process, because they are higher than 5 in Mn/Fe ratio.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.927-933
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• 2022

We synthesized (C₁₀H₈N₂H)₂Cr₂O₇, The structure of the product was characterized with FT-IR(infrared) and elemental analysis. The oxidation of benzyl alcohol by (C₁₀H₈N₂H)₂Cr₂O₇ in organic solvents showed that the reactivity increased with the increase of the dielectric constant. The oxidation of alcohols was examined by (C₁₀H₈N₂H)₂Cr₂O₇ in DMF, acetone. As a resuit, (C₁₀H₈N₂H)₂Cr₂O₇ was found as efficicent oxidizing agent that converted benzyl alcohol, allyl alcohol, primary alcohol and secondary alcohols to the corresponding aldehydes or ketones(65%~95%). The selective oxidation of alcohols was also examined by (C₁₀H₈N₂H)₂Cr₂O₇ in DMF, acetone. (C₁₀H₈N₂H)₂Cr₂O₇ was selective oxidizing agent(15%~95%) of benzyl alcohol, allyl alcohol and primary alcohol in the presence of secondary ones. In the presence of DMF solvent with acidic catalyst such as H₂SO₄. (C₁₀H₈N₂H)₂Cr₂O₇ oxidized benzyl alcohol(H) and its derivatives. The Hammett reaction constant(ρ) was -0.69(308K). The observed experimental data were used to rationalize the hydride ion transfer in the rate determining step.

• Journal of Christian Education in Korea
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• v.69
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• pp.77-104
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• 2022

The purpose of this study was to investigate the research trend of forest play. The purpose of this study is to provide basic data for the vitalization of forest play research by analyzing the research period, research content, and research methods. For this study, 57 domestic master's and doctoral dissertations were extracted through the National Assembly Library and the Research Information Sharing Service(RISS) with the keywords of 'forest', 'play', and 'forest play'. The frequency and percentage were calculated by analyzing forest play research based on four criteria: research period, research content, research method, and research subject. As a result of the research, first, the trend of forest play research by period is from 2011 to 2021, with 49 articles (85.9%) for master's degrees and 8 articles (14.1%) for doctor's degrees. Second, the trend by research content was found to be 16 basic studies (28.1%) and 41 practical studies (71.9%). Forest play research is being actively conducted centered on practical research. Third, the trends by research method were in the order of 39 quantitative studies (68.4%), 17 qualitative studies (29.8%), and 1 literature study (1.8%). Forest play research is focused on quantitative research, and comparatively qualitative research and literature research account for a low proportion. Fourth, the trend by study subject was 56 single subject studies (98.2%). The single subjects were 52 children (91.2%), 3 teachers (5.2%), and 1 parent (1.8%). As for the mixed subjects, there is one study (1.8%) targeting children and parents, and it is necessary to conduct a study with mixed subjects. As for the study of material subjects, 42 articles (73.7%) in the natural environment, 13 articles (22.8%) in educational institutions, and 2 articles (3.5%) in the media were found in the order. Research on the home environment related to forest play is insufficient, so research on parents, children-parents, and home environment related to forest play should be conducted in the future.

• Journal of Korean Home Economics Education Association
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• v.33 no.4
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• pp.15-30
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• 2021

This study was conducted to investigate the utilization and satisfaction of meal-kits according to food-related lifestyle among total 357 adults who had experience in using meal-kits. This study can provide basic data for effective menu composition and directions toward improvement. The participants of the study were classified into 5 groups 'health-type group', 'economic-type group', 'safety-type group', 'tasty-type group' and 'convenience-type group'. The 'tastye-type group' were found to spend more on purchasing meal-kits than other groups with the higher proportion(36.66%) of spending '30,000-50,000'won(p<0.05), which is the highest price category. The important factors that contributed to purchasing a meal-kits were 'taste'(50.98%), and 'economic-type group' showed the highest tendency of considering taste (58.46%). About half(49.02%) of the respondents preferred 'Korean-food' for meal-kits as for the type of food. All groups highly preferred 'meat'(42.58%) as the main ingredient, particularly the 'tasty-type group'(53.33%)(p<0.001). The 'tasty-type group' showed the highest satisfaction on 'convenience of cooking'(4.05), and 'convenience-type group' showed the lowest satisfaction on the 'origin of ingredient'(2.98) among groups (p<0.01). The overall response indicated that most respondents are willing to use meal-kits in the future (97.20%); and 93.28% of respondents would recommend the purchase of meal-kits to others, where 'convenience of cooking/purchase' was the factor contributing most for recommending(67.23%). Taken together, 'taste' was the most important factor for all groups. And 'Convenience of cooking' was the factor contributing to satisfaction most while 'origin of ingredient' contributing the least. It is recommended for the growth of meal-kits industry, to improve the quality of the meal-kits products and develop various menus.

• Environmental and Resource Economics Review
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• v.31 no.2
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• pp.165-204
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• 2022

This study organized data from 2000 to 2014 for 20 grid-connected countries in Europe and analyzed the determinants of carbon emissions through the panel GLS method considering the problem of heteroscedasticity and autocorrelation. At the same time, the effect of introducing ETS was considered by dividing the sample period as of 2005 when the European emission trading system was introduced. Carbon emissions from individual countries were used as dependent variables, and proportion of generation by each source, power self-sufficiency ratio of neighboring countries, power production from resource-holding countries, concentration of power sources, total energy consumption per capita in the industrial sector, tax of electricity, net electricity export per capita, and size of national territory per capita. According to the estimation results, the proportion of nuclear power and renewable energy generation, concentration of power sources, and size of the national territory area per capita had a negative (-) effect on carbon emissions both before and after 2005. On the other hand, the proportion of coal power generation, the power supply and demand rate of neighboring countries, the power production of resource-holding countries, and the total energy consumption per capita in the industrial sector were found to have a positive (+) effect on carbon emissions. In addition, the proportion of gas generation had a negative (-) effect on carbon emissions, and tax of electricity were found to have a positive (+) effect. However, all of these were only significant before 2005. It was found that net electricity export per capita had a negative (-) effect on carbon emissions only after 2005. The results of this study suggest macroscopic strategies to reduce carbon emissions to green growth, suggesting mid- to long-term power mix optimization measures considering the electricity trade market and their role.

• Journal of agricultural medicine and community health
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• v.47 no.2
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• pp.90-98
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• 2022

Objective: This study aimed to provide basic data for preventing and managing sarcopenia by identifying the relationship between sarcopenia, malnutrition, and psychosocial factors among the elderly in the community. Methods: The study included 1,019 subjects aged 60 and over. "Possible sarcopenia" was defined by low handgrip strength with or without reduced physical performance. Nutrition was evaluated according to the mini nutrition assessment (MNA), and the psychosocial factors examined were self-efficacy, social isolation, fear of falling, and social capital (trust and participation). A logistic regression analysis was also performed on the relationship between risk of malnutrition, psychosocial factors, and sarcopenia. Results: MNA was significantly associated with social participation (OR = 1.747, p <0.001), fear of falling (OR = 2.905, p <0.001), and self-efficacy (high/low, OR = 0.654, p = 0.011). In model 3, which included both MNA and psychosocial factors, sarcopenia was significantly associated with MNA (OR = 2.529, p <0.001) and fear of falling (OR = 1.544, p = 0.045). Compared with the low self-efficacy group, the high group (OR = 0.589, p = 0.009) was significant. The factors related to possible sarcopenia include risk of malnutrition, fear of falls, and low self-efficacy. Conclusion: It will be necessary to improve self-efficacy so that individuals feel they can do activities of daily living themselves and to reduce their fear of falling through muscle strength and balance exercises. Finally, it is also necessary to increase regular participation in community social activities.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.5
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• pp.13-29
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• 2022

According to the revision of the Convenience Act for Persons with Disabilities, parks and park facilities where the first park development plan is established after December 4, 2021 are mandatory, and parks must be equipped with convenience facilities for the disabled. Hence, this study aims to derive the improvements of the park evaluation index by analyzing the park certification evaluation index, the building certification evaluation index of park facilities, and the evaluation reports of the current certification status cases. As a research method, first, the certification of parks and park facilities were compared and reviewed with the Park Green Act, and differences in the certification process and certification performance were compared and analyzed. Second, differences and common items were derived by analyzing barrier free (BF)-certification evaluation indicators for parks and buildings. Third, improvement plans were derived after analyzing differences and problems in 4 BF-certified parks and four building certification cases of park facilities in certified parks, focusing on the self-evaluation report and examination results. As a result of analyzing the park and building evaluation indicators, the items for which the evaluation purpose, evaluation method, and evaluation items were commonly applied to 7 access roads for each facility, 5 parking areas for the disabled, 2 guide facilities for information facilities, 14 in 5 categories of sanitation facilities, and 1 for other facilities. In the case of sanitation facilities, there is no case where it was evaluated as a park. If the park does not have an attached toilet, the park is certified as a building. Hence, it would be essential to establish the concept of an attached toilet and discuss the application of the evaluation index on the park sanitation facility. The score of buildings in parks and park facilities was lower than that of the self-evaluation results, and the certification grades of buildings declined in three cases. The items with the highest standard deviation were BF walking continuity for parks and the path to the main entrance among access roads for buildings. As a result of analyzing the park and building evaluation results of 19 common evaluation items except for sanitary facilities, the difference in the grades of the evaluation items for each case site except for one item appeared. Therefore, applying common detailed calculation criteria for items evaluated in common with parks and buildings is needed. Since sanitation facilities have no cases of park certification and are not certified as buildings, it is essential to establish the concept of attached toilets and discuss the application of park sanitation evaluation indicators. It is necessary to develop an evaluation index suitable for the characteristics of the park, such as adjusting the items that are not evaluated in parks and establishing an evaluation index considering the ones of parks. It expects that this study would be used as primary data for improving park certification indicators.

• Journal of the Korean Society of Tobacco Science
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• v.24 no.1
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• pp.67-73
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• 2002

In light of addressing consumer health concern, coping with anti-tobacco movement, and promoting new product, tobacco industry is actively pursuing to make a new generation of cigarettes with low tar and nicotine deliveries, and less harmful substances. Low tar and low nicotine cigarettes increases their market shares dramatically world wide, especially in KT&G, multinational tobacco companies, EU countries, even in China regulated by CNTC to set up yearly target to lower tar and nicotine deliveries. On the other hand, to design a new cigarette with reduced harmful substances begins to gain speed. The "modified Hoffmann list" publishes thirty plus substances in tobacco leaf and main smoke stream, which is the prime suspect causing health problems. Various ways and means are developed to reduce such components including new tobacco breeds, new curing method, tobacco leaf treatment before processing, selected filtration system, innovated casing system to reduce free radicals, as well as some non conventional cigarette products. In TSRC held this year, the main topic is related to reduce tobacco specific nitrosamines in tobacco leaf. The new generation of cigarette is in the horizon. It still needs a lot help to produce commercial products with satisfied taste and aroma characters. The flavor industry is not regulated by many governments demanding which ingredients might or might not be for tobacco use. However, most of the cigarette companies self impose a list of ingredients to guide flavor suppliers to design flavors. Unfortunately, the number of ingredients in those lists is getting shorter every year. It is understandable that the health is not the only reason. Some cigarette companies are playing safe to protect the company from potential lawsuit, while others are just copying from their competitors. Moreover, it is obvious that it needs more assistance from casings and flavors to design new generation of cigarettes with missing certain flavor components in tobacco leaf and main smoke stream. These flavor components are either non-existed or at lower level at new form of cured tobacco leaf or filtered in the main smoke stream along with reduced harmful substances. The use of carbon filters and other selected filtration system poses another tough task for flavor system design. Specific flavor components are missing from the smoke analysis data, which brings a notion of "carbon taste" and "dryness" of mouth feel. It is ever more demanded by cigarette industry to flavor suppliers to produce flavors as body enhancer, tobacco notes, salivating agents, harshness reducer, and various of aromatic notes provided they are safe to use. Another trend is that water based flavor or flavor with reduced ethanol as solvent is gaining popularity. It is preferred by some cigarette companies that the flavor is compounded with all natural ingredients or all ingredients should he GMO free. The new generation of cigarettes demands many ways of new thinking process. It is also vital for tobacco industry. It reflects the real needs for the consumers that the cigarette product should be safe to use as well as bearing the taste and aroma characters smokers always enjoyed. An effective tobacco flavor system is definitely a part of the equation. The global trend of tobacco industry is like trends of any other industries lead by consumer needs, benefited with new technology availability, affected by the global economy, and subjected for various rules and regulations. Anti-tobacco organizations and media exceptionally scrutinize cigarette, as a legal commercial product. Cigarette is probably the most studied commercial product for its composition, structure, deliveries, effects, as well as its new developmental trend. Therefore, any new trend of cigarette development would be within these boundaries. This paper is trying to point out what it would be like for tobacco industry in the next few yews and what concerns the tobacco industry. It focuses mostly on the efforts to produce safer cigarettes. It is such a vital task for the tobacco industry and its affiliate industries such as cigarette papers, filters, flavors, and other materials. The facts and knowledge presented in this paper might be well known for the public. Some of the comments and predictions are very much personal opinion for a further discussion.

• Korean Journal of Plant Resources
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• v.36 no.1
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• pp.1-14
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• 2023

This study measured the antioxidant activity and phytochemical content of 192 Boehmeria nivea var. tenacissima (Gaudich.) Miq. collected from six regions in order to identify the possibility of its industrial application. Two antioxidant activity assay (DPPH radical scavenging activity and ABTS radical scavenging activity) and two phytochemical content assay (total polyphenol content (TPC) and total flavonoid content (TFC)) of 192 samples were analyzed. The results showed that the DPPH radical scavenging activity of 192 samples was ranged from 0.02 to 1.35 mgAAE/g, and among them, the samples collected from Goheung (0.53 ± 0.37) and Ulleungdo (0.52 ± 0.28) showed the highest activity. The ABTS radical scavenging activity was showed the ranged from 0.07 to 1.81 mgAAE/g, and the samples collected at Ulleungdo (0.47 ± 0.36) showed the highest activity. The total polyphenol content of 192 samples was 18.6 to 234.8 ugGAE/g, and the samples collected at Mokpo (93.4 ± 34.7) and Jindo (90.4 ± 24.5) showed the highest content. The total flavonoid content was 0.10 to 1.22 mgQE/g and the samples collected at Ulleungdo (0.49 ± 0.31) showed the highest content. In the correlation analysis, there was no significant relationship between the environmental conditions and the antioxidant activity. The total polyphenol content showed a positive correlation with daily temperature difference, and negative correlation with average wind speed and average humidity, and total flavonoid content showed negative correlations with the average temperature, maximum temperature, and minimum temperature. This result can be used as a basic data establish the cultivation conditions of B. nivea var. tenacissima (Gaudich.) Miq. as a functional raw material to increase the usefulness of B. nivea var. tenacissima (Gaudich.) Miq..

• Journal of the Korean Society of Earth Science Education
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• v.16 no.1
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• pp.143-152
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• 2023

This study was conducted on 115 students from 4 classes of 2nd year intensive courses at B University of Education. Elementary preservice teachers were surveyed on what teaching methods they were aware of regarding the subject of elementary science astronomy. Recognition data of 80 people from whom the questionnaire was collected were analyzed. For this study, a 5-day survey was conducted. Elementary preservice teachers complained of difficulties in teaching methods in the astronomy area among various areas of the science department. The purpose of this study was to find out what difficulties elementary preservice teachers have in teaching elementary science astronomy topics, and to find more efficient teaching methods for teaching astronomy topics. The topic of the survey was set by discussing with the preparatory elementary teachers about what kind of survey to use in teaching the subject of elementary science astronomy. There are many topics for elementary science astronomy, but two questionnaires were prepared focusing on the unit on the earth and the moon. 'What does the earth look like?' in Unit 4 (1/10) of the 3rd year, 1st semester In Unit 2 (1/11) of the 1st semester of the 6th grade, it was set as 'What does the moon look like?'. Candidly describe how to teach the subject of astronomy to elementary school students by mobilizing all the background knowledge of preparatory elementary teachers. The results of these surveys were visualized and displayed using Netminer as a language analysis method, and the contents of the responses to the actual surveys by pre-service elementary school teachers were described and interpreted. Based on these results, preparatory elementary teachers tried to suggest a more efficient teaching method for the subject of elementary science astronomy. In addition, basic procedures and methods for lecturing on the subject of elementary science astronomy were presented. A more efficient teaching method for teaching elementary science astronomy subjects to pre-service elementary teachers was suggested.