• Title/Summary/Keyword: 분산특성

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Phase evaluation of Fe/Co pigments coated porcelain by rietveld refinement (리트벨트 정밀화법에 의한 Fe/Co 안료가 코팅된 도자기의 상분석)

  • Nam-Heun Kim;Kyung-Nam Kim
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.33 no.5
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    • pp.174-180
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    • 2023
  • Porcelain (white ware, celadon ware) coated with a ferrous sulfate and ferrous/cobalt sulfate was sintered at 1250℃. The specimens were investigated by HR-XRD, FE-SEM, HR-EDS, and UV-vis spectrophotometer. Through X-ray rietveld quantitative analysis, quartz and mullite were found to be the main phases for white ware, and mullite and plagioclase were found to be the main phases for celadon ware. When the pigment of ferrous/cobalt sulfate was applied, were identified as an andradite phase for celadon ware and a spinel phase for the white ware, and the amorphous phase, respectively. The L* value, which was the brightness of the specimen, was 72.01, 60.92 for white ware and celadon ware, respectively. The ferrous and ferrous/cobalt pigment coated porcelain had L* values of 44.89, 52.27 for white ware and celadon ware, respectively; with a* values of 2.12, 1.40, an d at b* values of 1.45 and 13.79. As for the color of the specimens, it was found that the L* value was greatly affected by the white ware, and the b* value differed greatly depending on the clay. It was thought to be closely related to the production of the secondary phase such as Fe2O3 and andradite phase produced in the surface layer.

Effect of aquatic walking exercise on body composition, hs-CRP, insulin resistance and blood pressure in obese elderly women (12주간 수중걷기운동이 비만 노인 여성의 신체조성, hs-CRP, 인슐린 저항성 및 혈압에 미치는 영향)

  • Woo-Hyeon Son;Min-Seong Ha;Byeong Hwan Jeon;Hyun-Tae Park
    • Journal of the Korean Applied Science and Technology
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    • v.39 no.6
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    • pp.906-915
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    • 2022
  • The purpose of this study was to investigate the effects of aquatic walking exercise on body composition, hs-CRP, HOMA-IR, and blood pressure in obese elderly women. Twenty, obese elderly women[percent body fat(%BF) < 30%] composed of aquatic walking exercise group(EX, n=10), the control group(CON, n=10). The variables of body composition, hs-CRP, HOMA-IR, and blood pressure were measured in all the subjects pre and post of 12 weeks aquatic walking exercise(RPE 11-14, 3 times per week, 50 mins). The test data were analyzed by paired t-test and repeated ANOVA, and the alpha level of p<.05 was set for all tests of significance. %BF (p<.05), insulin (p<.01), HOMA-IR (p<.01) and SBP (p<.05) were significantly decreased in EX group compared to CON group. These results suggest that 12 weeks of aquatic walking exercise improves %BF, HOMA-IR, and blood pressure. Thus, this proposed aquatic walking exercise modality can be a useful therapy to improve both obese and cardiovascular disease in obese elderly women.

A study on the relationship between learning flow, learning satisfaction, academic self-efficacy, academic achievement, and academic stress of nursing college students who experienced online lectures in a non-face-to-face learning environment (비대면 학습환경에서 온라인 강의를 경험한 간호대학생들의 학습몰입, 학습만족도, 학업적 자기효능감, 학업성취도, 학업스트레스간의 관계연구)

  • Yang, Seung Ae
    • Journal of Internet of Things and Convergence
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    • v.9 no.6
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    • pp.63-73
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    • 2023
  • The purpose of this study is to identify the level of learning flow, learning satisfaction, academic self-efficacy, academic achievement, and academic stress of nursing students who experienced non-face-to-face online lectures, and to investigate the correlation between variables and the factors affecting academic stress. The data of this study was collected from 143 students at a nursing college in Seoul, through a Google online questionnaire from September 1, 2023 to September 25, 2023, and descriptive statistics, Student's t-test, analysis of variance, Pearson's Correlation, and linear multiple regression were conducted using SPSS Statistics 25.0. Following an analysis of the difference according to general characteristics, academic stress showed significant difference according to Motivation for applying to department(F=4.465, p=.005) and Major satisfaction(F=36.499, p=.000) of the subjects. The result of analyzing the correlation academic stress was negatively correlated with learning flow (r=-.464, p<.010), academic self-efficacy (r=-.522, p<.010), and academic achievement (r=-.379, p<.010), but learning satisfaction was not correlated with academic stress. Variables affecting academic stress were major satisfaction (𝛽=.367, p<.01), learning flow (𝛽=-.186, p<.05), and academic self-efficacy (𝛽=-.241, p<.05), and the explanatory power for academic stress was 40%. The results of this study can be used as basic data for intervention programs for relieving academic stress of nursing students.

A Study on the Revitalization of Digital Contents Industry (디지털콘텐츠 산업육성 사업 구조개편 방안 연구)

  • Jin-Hyeon Chang
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.5
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    • pp.159-167
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    • 2023
  • Due to the convergence of digital technology and the rapidly changing characteristics of the digital industry, the development projects in each technology field that have been carried out so far have blurred the boundaries of the business, dispersed business effects, and reached the limit in fostering a flexible industry that accommodates technological development. It appears that Therefore, the goal is to support the policy of the digital content development project by suggesting a plan to reorganize the structure and improve the management system of the digital content industry development project to effectively respond to the changing direction of the future digital content industry. Through structural analysis and diagnosis of government supported projects, it was proposed to reorganize the existing 19 key projects and 49 detailed projects into 7 key projects projects and 17 detailed projects. As a plan to improve the project management system, there are too many project implementation agencies and the absence of a general agency for detailed project support management, which limits the promotion of large-scale projects for organic linkage between projects and market creation. To improve this, a general agency that oversees the project management function was selected, and it was suggested that there was a need to unify project management into a general organization to manage the project efficiently.

A Study on the Performance of Ni Catalysts in Biogas Steam Reforming: Impact of Supports and Precipitation Agent Injection Rates (바이오가스 수증기 개질 반응용 Ni 촉매 성능 연구: 지지체 및 침전제 주입 속도에 따른 영향)

  • Ji-Hyeon Gong;Min-Ju Kim;Kyung-Won Jeon;Won-Jun Jang
    • Clean Technology
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    • v.29 no.4
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    • pp.327-332
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    • 2023
  • This study investigated synthesis gas production via steam reforming of biogas. Ni-Al2O3 and Ni-CeO2 catalysts were synthesized using the co-precipitation method, with controlled precipitation agent injection rates. Catalytic performances were tested at various temperatures, with a gas composition ratio of CH4:CO2:H2O = 1:0.67:3 and a gas hourly space velocity (GHSV) of 647,000 mL h-1 gcat-1. The rate of precipitation agent injection influenced the characteristics of the catalysts depending on the type of support used. As the temperature increased, both the CO2 reforming of methane and the reverse water gas shift reactions occurred. The Ni-Al2O3 catalyst, synthesized with a single injection of the precipitation agent, exhibited the best catalytic activity under conditions with sufficient steam supply among the prepared catalysts, due to its high Ni dispersion.

The Effects of Gamification E-Learning Classes Based on Self-Determination Theory on University Students' Class Participation, Learning Immersion, Teaching Presence (자기결정성 이론에 기반한 게이미피케이션 이러닝 수업이 대학생의 수업참여도, 학습몰입도, 교수실재감에 미치는 효과)

  • Myoung-Heo;Sang-woo Jin
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.6
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    • pp.73-83
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    • 2023
  • This study is a descriptive survey to develop a gamification e-learning class based on self-determination theory and to check its effectiveness. The data collection period was from March 1 to June 15, 2023, and 59 students at G University in G Metropolitan City were surveyed on class participation, learning immersion, and teaching presence before and after the course. IBM SPSS/Win 26.0 was used to analyze the collected data, and descriptive statistics, analysis of variance (ANOVA), and analysis of covariance (ANCOVA) were conducted. The results showed that the self-determination-based gamification class significantly improved students' class participation, learning engagement, and teaching presence (p<.05). An analysis of covariance (ANCOVA) was conducted to determine whether the general characteristics of the participants affected the results of the post-test, and gender affected the post-test results of learning engagement, with an effect of 7.9%. Based on the results of this study, it can be seen that self-determination-based gamification e-learning class is effective in improving learners' class participation, learning engagement, and teaching presence. As the demand for e-learning in universities is expanding, self-determination-based gamification e-learning classes should be developed in various fields of liberal arts and majors.

Living Conditions and Life Satisfaction of Single-person Households by Life Cycle : An Analysis of Single-person Households in Kimpo, South Korea (1인가구의 생애주기별 생활실태 및 생활만족도 : 김포시 1인가구를 중심으로)

  • Kim, Jung Eun;Park, Jeongyun;Seo, Jiwon;Song, Hyerim
    • Journal of Family Resource Management and Policy Review
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    • v.27 no.3
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    • pp.21-37
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    • 2023
  • This study examines the living conditions and life satisfaction of single-person households according to their life cycle. The survey was conducted from August to October 2022, and respondents were single-person households from Kimpo, South Korea. The respondents were categorized to three groups namely, young, middle-aged, and older adults by life cycle, and items regarding their sociodemographic background, personal life, family relations, and life satisfaction were included in the analysis. Descriptive statistics, Chi-square analysis, analysis of variance, and multiple regression analysis were performed. The key findings were as follows. First, significant differences were found according to life cycle in the respondents' diet, clothing, housing, financial and home management, self-care, and leisure life. Second, the variables that significantly affected the level of life satisfaction of single-person households were the life cycle with young adults showing a higher level of satisfaction; having a family member to care; living alone voluntarily, discrimination experience; community awareness; and ties with the local community. Based on the results, it is clear that single-person households have different needs and problems in each stage of life cycle. Thus, to reflect the different experiences and needs of single-person households by life cycle, tailored policy and programs should be provided for young, middle-aged, and older adult single-person households.

Analysis of Petrological Characteristics and Lacquer Gilding Materials of the Stone Buddha Head Excavated from the Temple Site No.4 of Yaksugok-Valley in Namsan Mountain, Gyeongju (경주 남산 약수곡 제4사지 출토 석재 불두의 암석학적 특징과 옻칠 도금 재료 분석)

  • Yu Jia;Lee Myeongseong;Lee Eunwoo
    • Conservation Science in Museum
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    • v.30
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    • pp.47-70
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    • 2023
  • In 2019, the first excavation survey was conducted at the Temple Site No. 4 of Yaksugok Vally in Namsan Mountain, Gyeongju to determine the original location of the headless stone Buddha statue and the structure of the temple site. The survey excavated a stone Buddha head that was confirmed in a comparative analysis to be petrologically and mineralogically identical to a headless stone seated Buddha statue found derelict nearby. Traces of gold leaf and black adhesive were found on a portion of the right side of the face of the Buddha head buried in the ground. Since it is exceedingly rare for lacquer and gilding techniques to have been applied to a large stone Buddha statue without a base layer, this study examines the gilding techniques of the time by analyzing the characteristics of the materials used. In this process, the structure of the gold foil was observed through analytical microscopy and scanning electron microscopy with energy dispersive X-ray spectrometry, and the gold (Au) component was identified. As a result of analyzing the black adhesive using pyrolysis-gas chromatograph/mass spectrometry (pyrolysis-GC/MS), pyrolysis compounds such as hydrocarbons, fatty acids, catechol, and catechol oxidation products were detected. This was identical to the characteristics identified upon analyzing lacquer collected from species of lacquer tree whose main component is urushiol. Therefore, it was confirmed that the stone Buddha head excavated from the Temple Site No. 4 of Yaksugok Valley was separated from a nearby stone seated Buddha statue, and that the gold foil was attached using lacquer sap collected from lacquer trees, which grow in Korea, China, and Japan.

Research on the Development of Distance Metrics for the Clustering of Vessel Trajectories in Korean Coastal Waters (국내 연안 해역 선박 항적 군집화를 위한 항적 간 거리 척도 개발 연구)

  • Seungju Lee;Wonhee Lee;Ji Hong Min;Deuk Jae Cho;Hyunwoo Park
    • Journal of Navigation and Port Research
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    • v.47 no.6
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    • pp.367-375
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    • 2023
  • This study developed a new distance metric for vessel trajectories, applicable to marine traffic control services in the Korean coastal waters. The proposed metric is designed through the weighted summation of the traditional Hausdorff distance, which measures the similarity between spatiotemporal data and incorporates the differences in the average Speed Over Ground (SOG) and the variance in Course Over Ground (COG) between two trajectories. To validate the effectiveness of this new metric, a comparative analysis was conducted using the actual Automatic Identification System (AIS) trajectory data, in conjunction with an agglomerative clustering algorithm. Data visualizations were used to confirm that the results of trajectory clustering, with the new metric, reflect geographical distances and the distribution of vessel behavioral characteristics more accurately, than conventional metrics such as the Hausdorff distance and Dynamic Time Warping distance. Quantitatively, based on the Davies-Bouldin index, the clustering results were found to be superior or comparable and demonstrated exceptional efficiency in computational distance calculation.

A Study on Awareness of Nuclear Power Generation and Fukushima Contaminated Water (원자력발전과 후쿠시마 오염수에 대한 인식 연구)

  • Yeon-Hee Kang;Sung Hee Yang;Yong In Cho;Jung-Hoon Kim
    • Journal of the Korean Society of Radiology
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    • v.18 no.2
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    • pp.109-117
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    • 2024
  • In order to determine the level of awareness of nuclear power generation and Fukushima contaminated water, this study conducted an online survey targeting the general public living in the Busan area and analyzed a total of 201 questionnaires. Independent samples t-test and one-way analysis of variance were conducted to verify differences in variables according to the characteristics of the study subjects, and correlation analysis was conducted to confirm the correlation between variables. First, the results of the study showed that women had a more negative perception of nuclear power generation and Fukushima contaminated water than men. In terms of age, it was found that people in their 40s and older had a high level of negative perception. In terms of political inclination, progressive respondents showed a higher negative perception toward nuclear power generation and Fukushima contaminated water. Second, information on nuclear energy was most often collected through the Internet, broadcasting, and SNS. Third, the higher the negative perception of nuclear power generation, the more negative the results were in terms of issues of concern following the discharge of contaminated water at the Fukushima nuclear power plant. Nuclear power cannot be separated from human life. Therefore, it is believed that accurate information and a knowledge delivery system are needed to ensure correct awareness of nuclear power generation.