• Title/Summary/Keyword: Analysis of Factors

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Dosimetric Analysis of Respiratory-Gated RapidArc with Varying Gating Window Times (호흡연동 래피드아크 치료 시 빔 조사 구간 설정에 따른 선량 변화 분석)

  • Yoon, Mee Sun;Kim, Yong-Hyeob;Jeong, Jae-Uk;Nam, Taek-Keun;Ahn, Sung-Ja;Chung, Woong-Ki;Song, Ju-Young
    • Progress in Medical Physics
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    • v.26 no.2
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    • pp.87-92
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    • 2015
  • The gated RapidArc may produce a dosimetric error due to the stop-and-go motion of heavy gantry which can misalign the gantry restart position and reduce the accuracy of important factors in RapidArc delivery such as MLC movement and gantry speed. In this study, the effect of stop-and-go motion in gated RapidArc was analyzed with varying gating window time, which determines the total number of stop-and-go motions. Total 10 RapidArc plans for treatment of liver cancer were prepared. The RPM gating system and the moving phantom were used to set up the accurate gating window time. Two different delivery quality assurance (DQA) plans were created for each RapidArc plan. One is the portal dosimetry plan and the other is MapCHECK2 plan. The respiratory cycle was set to 4 sec and DQA plans were delivered with three different gating conditions: no gating, 1-sec gating window, and 2-sec gating window. The error between calculated dose and measured dose was evaluated based on the pass rate calculated using the gamma evaluation method with 3%/3 mm criteria. The average pass rates in the portal dosimetry plans were $98.72{\pm}0.82%$, $94.91{\pm}1.64%$, and $98.23{\pm}0.97%$ for no gating, 1-sec gating, and 2-sec gating, respectively. The average pass rates in MapCHECK2 plans were $97.80{\pm}0.91%$, $95.38{\pm}1.31%$, and $97.50{\pm}0.96%$ for no gating, 1-sec gating, and 2-sec gating, respectively. We verified that the dosimetric accuracy of gated RapidArc increases as gating window time increases and efforts should be made to increase gating window time during the RapidArc treatment process.

Anti-atopic Effects of Castanea crenata Inner Shell Extracts Fermented by Lactobacillus bifermentans (Lactobacillus bifermentans로 발효한 율피의 항아토피 효과)

  • Kim, Bae Jin;Son, Woo Rim;Choi, Mi Ok;Jo, Seung Kyeung;Jung, Hee Kyoung;Lee, Jin Tae;Kim, Hak Yoon;Kwoen, Dae Jun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.9
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    • pp.1378-1386
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    • 2013
  • Atopic dermatitis (AD) is a common skin disease characterized by chronic and relapsing inflammatory dermatitis with immunological disturbances. In spite of the continuous increase in the incidence of AD, it is regrettable that till date there is no effective treatment to treat the same. Therefore, the present study was designed to examine the possible anti-atopic effects of Castanea crenata inner shell extracts fermented by Lactobacillus bifermentans (FCS) in 2,4-dinitrochlorobenzene (DNCB) induced AD in NC/Nga mice. Based on the results of HPLC analysis, we found that FCS contains anti-inflammatory factors such as gallic acid (10.18 mg/g) and ellagic acid (2.14 mg/g). The groups that we have used in this study included 0.1%, 1%, 5% fermented Castanea crenata inner shell extracts (FCS 0.1, FCS 1, FCS 5), 1,3-butylene glycol treated control (AD), and normal mice. After topical FCS treatment, we observed that the clinical severity score for AD was lower in both the FCS 1 and FCS 5 groups than the AD group. We also proved beyond doubt that there was improvement of melanin, erythema and skin moisture indices in the FCS 5 group. Spleen index and gene expression levels of pro-inflammatory cytokines such as IL-$1{\beta}$ and TNF-${\alpha}$ were significantly decreased in the FCS 5 group compared to the AD group (P<0.05). Further, we also found that the level of serum immunoglobulin E (IgE) in the FCS-treated group was decreased in a concentration-dependent manner. The results of our study suggest that FCS can be effectively used as a cosmeceutical ingredient for both the prevention and improvement of AD.

Therapeutic Effects of Curdrania tricuspidata Leaf Extract on Osteoarthritis (골관절염 실험모델에서 꾸지뽕나무 추출물의 골관절염 억제효과 연구)

  • Nam, Da-Eun;Kim, Ok Kyung;Lee, Jeongmin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.5
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    • pp.697-704
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    • 2013
  • The inhibitory effect of ethanol extracts from Curdrania tricuspidata leaves (CTL) on osteoarthritis was investigated in primary cultured rat cartilage cells and a monosodium-iodoacetate (MIA)-induced arthritis rat model. To identify the effects of CTL 80% ethanol extracts (CTL80) and CTL 10% ethanol extracts (CTL10) against $H_2O_2$ treatment in vitro, cell survival was measured by the MTT assay. Cell survival after $H_2O_2$ treatment increased with CTL80 and CTL10 close to normal up to $300{\mu}g/mL\;H_2O_2$. The mRNA expression of matrix metalloproteinases (MMPs) was determined MMP-7 and MMP-13 (known catabolic factors), were significantly inhibited by CTL 80 and CTL10; a $200{\mu}g/mL$ dose of CTL80 especially decreased MMP-13 expression. In vivo, osteoarthritis was induced by an intra-articular injection of MIA into the knee joints of rats, then CTL80 and CTL10 orally administered daily for 35 days. After the animals were sacrificed, histological evaluations of their knee joints revealed a reduction in polymorphonuclear cell infiltration and smooth synovial lining in the CTL80-500 group. Micro-CT analysis of hind paws from CTL80-500 and CTL10 showed a protection against osteophyte formation, soft tissue swelling, and bone resorption. In conclusion, CTL ethanol extracts are effective in ameliorating joint destruction and cartilage erosion in MIA-induced rats. CTL decreases and normalizes articular cartilage through preventing extracellular matrix degradation and chondrocyte injury, and could potentially serve as a therapeutic treatment for humans.

Buyers' Trust in a Brand and Brand Loyalty in the business-to-business (산업재 시장에서 브랜드 신뢰와 브랜드 충성도에 관한 연구)

  • Han, Sang-Rin;Sung, Hyung-Suk
    • Proceedings of the Korean DIstribution Association Conference
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    • 2005.11a
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    • pp.29-51
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    • 2005
  • Brands are important in the consumer market. They are the interface between consumers and the company, consumers may develop loyalty to brands. also, The late development of industrial marketing explains the near absence of research on Brand Equity in business to business. With recent change, industrial companies have shifted from a production focus to a customer focus. industrial brand is fast developing. The basic purpose of this study is to investigate industrial brand trust and loyalty affecting the Result of business relationship between industrial buyers and suppliers. Factors hypothesized to influence trust in a brand include a number of brand characteristics, company characteristics and consumer-brand characteristics. This research presented a comprehensive constructive model consisting of components of industrial brand trust and loyalty, and then propose the research model base on prior researches and studies about relationships among components of industrial brand loyalty. Data were gathered from respondents who work in industrial buying center. For this study, Data were analyzed by SPSS 10.0 and AMOS 4.0. The results of this research analysis were as fallow. Industrial brand trust and loyalty were positively related with a number of industrial brand characteristics, supplier characteristics and buyer-brand characteristics. relationship commitment. This research newly proposed the concept of 'industrial brand trust and loyalty affecting the Result of business relationship between industrial buyers and suppliers'

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Environmentally Available Potential of Renewable Energy in Korea: Onshore Wind and Photovoltaic (육상풍력 및 육상태양광의 환경적 가용입지 분석)

  • Lee, Young-Joon;Park, Jong-Yoon
    • Journal of Environmental Impact Assessment
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    • v.30 no.6
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    • pp.339-354
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    • 2021
  • The purpose of this study is to provide valuable information and data by analyzing the environmental status and potential forrenewable energy projects (or plans) based on environmental assessment (EA) data, so that more objective and scientific environmental assessments can be conducted. The study also suggests regional directions that could satisfy the goals of nature conservation and renewable energy. Based on the analysis of EA data that was conducted up until June 2019, the study analyzed the size, location and characteristics of both onshore wind power and onshore photovoltaic. The environmentally available potential by region was also derived by considering the main constraints and requirements related to the potential siting ofrenewable energy projects at the EA. Based on EA data, 63 out of 80 (79%) onshore wind power projects are shown to be located in mountainous areas. For onshore photovoltaic projects, a total of 7,363 projects were subjected to environmental assessment over the country. The environmentally potential area for onshore wind power, considering all the environmental regulatory factors, is 2,440 km2. For onshore photovoltaic, the environmentally available area estimated as idle farmland is 2,877 km2. The distribution and characteristics of the environmentally available potential of the region may be the most important factor that local governments should bear in mind in terms of promoting renewable energy development projects in the region. Based on the results of this study, even if we consider the national energy plan including the expected future increase, as well as environmental goals and socio-economic acceptance through an environmental assessment, the available resources forrenewable energy projects are not insufficient. It is possible to examine the adequacy of the target distribution rate of renewable energy sources by region taking into consideration the quantitative and scientific results such as the environmentally available potential data derived from this study.

A Study on the Current Situation and Direction of Social Work Field Practicum - Focused on Cyber University - (사회복지현장실습교육의 현황과 방향에 관한 연구 -사이버대학교를 중심으로-)

  • Bae, Na-Rae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.12
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    • pp.197-211
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    • 2018
  • This is an exploratory study on the status of the social work field practicum at a cyber university. The purpose is to investigate the current situation and improvement plan of the social work field practicum. A qualitative analysis was conducted with 11 professors who have instructed the social work field practicum at cyber universities. The social work field practicum based on the experiences of the professors is investigated, and this paper analyzes the status according to students, schools, practitioners, and institutions. In order to improve the quality of the social work field practicum, factors for improvement were analyzed through the efforts of students, schools, the Korean social workers' association, institutional improvements, and social welfare instructors. The results of the study are as follows. Students, schools, and training organizations should recognize the importance of the social work field practicum and must strive for systematic and consistent education. It is also important to remember that a social worker is not a professional with simple qualifications, but an expert with a philosophy, values, and ideologies. The direction for improvement in the social work field practicum is as follows. When constructing a social welfare curriculum, the school should have a realistic curriculum and teaching method that can enhance the sense of the field. The student should not be qualified as a social worker only as a vague investment for the future, but should have the professional ability to serve clients as a social worker and to give professional help to clients, considering the best welfare service for human beings. Institutions should provide a place for students to integrate theory and practice in vital social welfare experiences as social workers. The Republic of Korea is now facing an age with one million social workers. In order to open the future of social welfare in Korea, we need united endeavors with government that can develop students as pre-social workers and establish universities, institutions, and their systems for a substantial social work field practicum.

Exploring the Role of Collaborative Reflection in Small Group Argumentation: Focus on Students' Epistemic Considerations and Practices (소집단 논변 활동에서 협력적 성찰의 역할 탐색 -학생들의 인식적 고려와 실행을 중심으로-)

  • Cho, Hanbit;Ha, Heesoo;Kim, Heui-Baik
    • Journal of The Korean Association For Science Education
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    • v.39 no.1
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    • pp.1-12
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    • 2019
  • This study aims to explore students' epistemic practices and considerations, which are explained as underlying epistemic thoughts that guide their epistemic practices, during argumentation in science classrooms. We also investigated how collaborative reflection facilitated the development of such epistemic considerations. Two seventh-grade classes participated in this study by engaging in argumentation activities and collaborative reflection after classes. A group with students' change in epistemic aspects and the influence of collaborative reflection clearly revealed from their practices was chosen as a focus group. We recorded their class discussions and collaborative reflections with the researchers. Transcriptions of the recordings and checklists we collected during the collaborative reflections were used for analysis. Results showed evident changes in the students' epistemic considerations and practices and four factors facilitating such developments were identified. First, the researcher facilitating the students to recognize each other as collaborators during collaborative reflection led development of epistemic considerations on "audience using the knowledge products." Second, the collaborative reflection facilitated construction of context for peer interactions where the students encouraged each other to participate in the discussion, resulting in the development of other students' epistemic considerations on "justifications in knowledge products." Third, the items provided on the checklists explicitly delineated expectations on their practices in argumentation, also facilitating development of epistemic considerations. Lastly, the students' imitation of the researcher's pattern of discourse facilitated construction of causal explanation and development of epistemic considerations on "nature of the knowledge products." This study will contribute to the construction of strategies that develop students' epistemic considerations and productive epistemic practices in argumentation.

The Association between HbA1c and the Biological Exposure Index for Heavy Metals in Community (지역사회 주민의 당화혈색소와 중금속 생체표지자와의 관련성)

  • Min, Young-Sun;Lee, Kwan
    • Journal of agricultural medicine and community health
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    • v.47 no.3
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    • pp.181-188
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    • 2022
  • Objectives: The prevalence of diabetes mellitus was approximately 16% in populations of over age 30 years, and deaths from diabetes mellitus became the sixth most prevalent cause of death by disease. To assess the relationship between HbA1c and heavy metal level in blood and urine, targeted residents were evaluated in a vast steel industrial complex. Methods: We selected 414 subjects for analysis after applying the following exclusion criterion: 18 persons with diabetes mellitus. They took part in a questionnaire survey and underwent blood and urinary assessments. HbA1c and lead (Pb) level were measured in blood and, cadmium (Cd), inorganic arsenic (iAs) and mercury (Hg) were evaluated in urine. Two subgroups were divided by HbA1c 6.5%. Each subgroup was divided by 10th, 20th, 30th, 40th, 50th, 60th, 70th, 80th and 90th percentile levels of biological exposure index of the heavy metals for logistic regression. Results: Odd ratios have a tendency to increase as they go from the 90th to the 10th percentile of cadmium. However, lead, arsenic and mercury did not have significant relationships with HbA1c. In correction of age, region, gender and smoking history, a higher distribution in the subgroup with cadmium above 0.8318 ㎍/g creatinine (30th percentile) was demonstrated in the subgroup with HbA1c levels above the 6.5%, with an odds ratio of 5.26 (95% C.I. ; 1.44~19.17). Conclusion: This study found a significant correlation between urinary levels of cadmium and HbA1c in correction of several factors. It is meaningful that this outcome may be used as a basis for a study to establish the acceptable limit of urinary cadmium in Korea.

Analysis of the impact of mathematics education research using explainable AI (설명가능한 인공지능을 활용한 수학교육 연구의 영향력 분석)

  • Oh, Se Jun
    • The Mathematical Education
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    • v.62 no.3
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    • pp.435-455
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    • 2023
  • This study primarily focused on the development of an Explainable Artificial Intelligence (XAI) model to discern and analyze papers with significant impact in the field of mathematics education. To achieve this, meta-information from 29 domestic and international mathematics education journals was utilized to construct a comprehensive academic research network in mathematics education. This academic network was built by integrating five sub-networks: 'paper and its citation network', 'paper and author network', 'paper and journal network', 'co-authorship network', and 'author and affiliation network'. The Random Forest machine learning model was employed to evaluate the impact of individual papers within the mathematics education research network. The SHAP, an XAI model, was used to analyze the reasons behind the AI's assessment of impactful papers. Key features identified for determining impactful papers in the field of mathematics education through the XAI included 'paper network PageRank', 'changes in citations per paper', 'total citations', 'changes in the author's h-index', and 'citations per paper of the journal'. It became evident that papers, authors, and journals play significant roles when evaluating individual papers. When analyzing and comparing domestic and international mathematics education research, variations in these discernment patterns were observed. Notably, the significance of 'co-authorship network PageRank' was emphasized in domestic mathematics education research. The XAI model proposed in this study serves as a tool for determining the impact of papers using AI, providing researchers with strategic direction when writing papers. For instance, expanding the paper network, presenting at academic conferences, and activating the author network through co-authorship were identified as major elements enhancing the impact of a paper. Based on these findings, researchers can have a clear understanding of how their work is perceived and evaluated in academia and identify the key factors influencing these evaluations. This study offers a novel approach to evaluating the impact of mathematics education papers using an explainable AI model, traditionally a process that consumed significant time and resources. This approach not only presents a new paradigm that can be applied to evaluations in various academic fields beyond mathematics education but also is expected to substantially enhance the efficiency and effectiveness of research activities.

Marginal bone loss between internal- and external- abutment connection type implants placed in the first molar area (제1대구치 위치에 식립된 단일 임플란트의 지대주 연결 유형에 따른 임플란트 주위골 흡수)

  • Seok-Hyun Lee;Eun-Woo Lee;Ha-Na Jung;Ok-Su Kim
    • Journal of Dental Rehabilitation and Applied Science
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    • v.39 no.1
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    • pp.32-44
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    • 2023
  • Purpose: The purpose of this study was to investigate the effect of implant connection type on marginal bone loss (MBL) and to analyze the factors that affect MBL. This study focuses on single implants planted in the upper and lower first molar area. Materials and Methods: A total of 87 implants from 68 patients were tracked for a period over 5 years. There were 57 external connection type (EC) implants and 30 internal connection type (IC) implants in 38 males and 30 females. The MBL and EA were measured from intraoral radiograph images taken after 5 years at most. Results: Significant difference in MBL between EC and IC type was observed in patients without GBR or diabetes. Patients without GBR exhibited an MBL of -0.065 ± 0.859 mm in EC type and -0.627 ± 0.639 mm in IC type (P = 0.025). Using multiple regression analysis, a statistically significant negative correlation was observed between MBL and conditions including implant-abutment connection type (β = -0.303), diabetes (β = -0.113), emergence angle > 30° (β = -0.234), and age (β = -0.776). Conclusion: Within this results, IC type implants had less MBL than EC type, and implant prosthesis with emergence angle over 30° showed greater MBL. To minimize the MBL of the implant and ensure implant stability, careful consideration should be given to the EA of implant prosthesis and its connection type.