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Understanding of Scientific Inquiry Developed by Beginning Science Teachers in Professional Learning Community (교사학습공동체 활동을 한 초임중등과학교사의 과학 탐구에 대한 이해)

  • Kim, Yurim;Choi, Aeran
    • Journal of The Korean Association For Science Education
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    • v.39 no.2
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    • pp.221-232
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    • 2019
  • Despite the continuing emphasis on the importance of scientific inquiry, research studies have commented that authentic scientific inquiry is not implemented in school science classroom due to a lack of understanding of scientific inquiry by the teacher. The purpose of this study is to investigate understanding of scientific inquiry developed by beginning teachers through open-ended questionnaire and semi-structured interview. They voluntarily set up the goal of inquiry-based classes, planned inquiry-based classes, shared and reflected their teaching experience in professional learning community for more than a year. It appeared that participant teachers understood scientific inquiry as 'what scientists do', 'process how students do science' and 'science teaching methods.' All teacher participants described scientific inquiry as 'what scientists do', and understood 'the process of doing scientific investigation to solve problems related to natural phenomenon' and 'the process of constructing scientific knowledge using scientific practice.' Two participant teachers seemed to understand scientific inquiry as a 'teaching method' based on the understanding of the process how scientists or students do science. Participant teachers had a limited understanding of scientific inquiry that it is the same as laboratory works or hands-on activities prior to engaging the professional learning community, but they developed an understanding of scientific inquiry that there are various ways to conduct scientific inquiry after engaging in professional learning community.

Accuracy of one-step automated orthodontic diagnosis model using a convolutional neural network and lateral cephalogram images with different qualities obtained from nationwide multi-hospitals

  • Yim, Sunjin;Kim, Sungchul;Kim, Inhwan;Park, Jae-Woo;Cho, Jin-Hyoung;Hong, Mihee;Kang, Kyung-Hwa;Kim, Minji;Kim, Su-Jung;Kim, Yoon-Ji;Kim, Young Ho;Lim, Sung-Hoon;Sung, Sang Jin;Kim, Namkug;Baek, Seung-Hak
    • The korean journal of orthodontics
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    • v.52 no.1
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    • pp.3-19
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    • 2022
  • Objective: The purpose of this study was to investigate the accuracy of one-step automated orthodontic diagnosis of skeletodental discrepancies using a convolutional neural network (CNN) and lateral cephalogram images with different qualities from nationwide multi-hospitals. Methods: Among 2,174 lateral cephalograms, 1,993 cephalograms from two hospitals were used for training and internal test sets and 181 cephalograms from eight other hospitals were used for an external test set. They were divided into three classification groups according to anteroposterior skeletal discrepancies (Class I, II, and III), vertical skeletal discrepancies (normodivergent, hypodivergent, and hyperdivergent patterns), and vertical dental discrepancies (normal overbite, deep bite, and open bite) as a gold standard. Pre-trained DenseNet-169 was used as a CNN classifier model. Diagnostic performance was evaluated by receiver operating characteristic (ROC) analysis, t-stochastic neighbor embedding (t-SNE), and gradient-weighted class activation mapping (Grad-CAM). Results: In the ROC analysis, the mean area under the curve and the mean accuracy of all classifications were high with both internal and external test sets (all, > 0.89 and > 0.80). In the t-SNE analysis, our model succeeded in creating good separation between three classification groups. Grad-CAM figures showed differences in the location and size of the focus areas between three classification groups in each diagnosis. Conclusions: Since the accuracy of our model was validated with both internal and external test sets, it shows the possible usefulness of a one-step automated orthodontic diagnosis tool using a CNN model. However, it still needs technical improvement in terms of classifying vertical dental discrepancies.

Elementary, Middle, and High School Students' Perception of Polar Region (초·중·고등학생들의 극지에 대한 인식)

  • Chung, Sueim;Choi, Haneul;Kim, Minjee;Shin, Donghee
    • Journal of the Korean earth science society
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    • v.42 no.6
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    • pp.717-733
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    • 2021
  • This study is aimed to provide basic data to set the direction of polar literacy education and to raise awareness of the importance of polar research. Elementary, middle, and high school students' perception of the polar region was examined in terms of current status of polar information, impression regarding polar regions, and awareness of related issues. The study included 975 students from nine elementary, middle, and high schools, who responded to 16 questions, including close-ended and open-ended items. The results suggest that students had more experiences regarding the polar region on audiovisual media, but relatively limited learning experiences in school education. The impression they had of the polar region was confined to the monotonous image of a polar bear in crisis, following the melting of the glacier due to global warming. The students formed powerful images by combining scenes they saw in audiovisual media with emotions. In terms of recognizing problems in the polar region, the students were generally interested in creatures, natural environment, and climate change, but their interests varied depending on their school level and their own career path. The students highly valued the scientist's status as agents to address the problems facing the region, and gave priority to global citizenship values rather than practical standards. Based on the results, we suggest the following: introducing and systematizing content focusing on the polar region in the school curriculum, providing a differentiated learning experience through cooperation between scientists and educators, establishing polar literacy based on concepts that are relevant to various subjects, earth system-centered learning approach, setting the direction for follow-up studies and the need for science education that incorporates diverse values.

Development and Validation of a Questionnaire on the Feasibility of a Mobile Dietary Self-Monitoring Application (식습관 관리 애플리케이션의 적용 가능성에 대한 설문지 개발 및 타당성 연구)

  • Lee, Heejin;Ahn, Jeong Sun;Lee, Jung Eun
    • Korean Journal of Community Nutrition
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    • v.27 no.2
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    • pp.146-157
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    • 2022
  • Objectives: This study aimed to develop and assess the content validity and internal consistency of a questionnaire on the feasibility of mobile dietary self-monitoring applications. Methods: We developed a feasibility questionnaire to assess the overall usage, convenience, usefulness, and satisfaction of mobile dietary applications. The initial draft of the questionnaire contained 17 items with yes/no, multiple-choice, and open-ended questions and 52 items on 5-point Likert scales. To validate the content, ten experts evaluated the relevance of the items for each subscale using a 5-point scale. We calculated the item-level content validity index (I-CVI) and scale-level content validity index (S-CVI). A total of 102 adults answered the questionnaires which reflected the experts' reviews. We conducted an exploratory factor analysis to determine the underlying structure of responses and categorized convenience, usefulness, and satisfaction. We also calculated Cronbach's alpha coefficient to examine the internal consistency of items in each subscale. Results: The S-CVI score of the items was 0.86, and we removed items with an I-CVI score of < 0.80. We combined, revised, or separated some remaining items and added one item as per the experts' comments. As a result, we included 16 items about overall usage and 42 sub-questions. Based on the responses of the 102 adults, we performed exploratory factor analysis using the principal axis method. We retained items with a factor loading of > 0.40, resulting in a final set of 35 questions (convenience: 15, usefulness: 12, satisfaction: 8 items). The Cronbach's alpha values of the three scales were 0.93, 0.91, and 0.91 for 1) usefulness, 2) convenience, and 3) satisfaction, respectively. Conclusions: We developed a feasibility questionnaire for mobile dietary self-monitoring applications and examined its content validity and internal consistency. Our questionnaire has the potential to measure the feasibility of mobile dietary self-monitoring applications.

Selection and Application of Pollinating Insects to Improve Seed Production of Buckwheat in Net House (메밀의 망실재배시 종자생산성 향상을 위한 수분곤충의 선발과 활용법 구명)

  • Kim, Su Jeong;Sohn, Hwang Bae;Nam, Jeong Hwan;Lee, Jong Nam;Suh, Jong Taek;Chang, Dong Chil;Kim, Yul Ho
    • Korean Journal of Plant Resources
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    • v.35 no.1
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    • pp.10-22
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    • 2022
  • This study investigated field data to understand the spatio-temporal distribution of pollinating insects and buckwheat flowers. We set the in-situ observation sites in different locations to get altitude and cropping system distribution data for five years (2016 to 2020) in Korea. Twenty-five different insect species, belonging to 8 orders, were recorded. Over the past five years, species from the orders Diptera and Hymenoptera were the principal visitors. Hymenoptera was mainly represented by honey bees (Apis cerana), while Diptera was represented by bean seed fly (Delia platura) and several other species. Some bees and other Hymenoptera species could, however, act as co-pollinators because of their high relative frequency and activity. Compared with open-field cultivation (conventional), the pollination mediating effect of flies and bees was superior in net house, so the yield was high, and it was also found to be slightly higher in the mixed treatment of flies and bees than in the single treatment. Based on the above results, flies and bees were found to be the most active pollinating insects in buckwheat and it is necessary to actively utilize the selected insects to improve buckwheat productivity. This relationship will be utilized in establishing the system of seed production on pollinating regulation of a primary plant.

High Performance Work System for Entertainment Business : An Analytic Network Process Approach (엔터테인먼트업의 고성과작업조직 : ANP 기법을 중심으로)

  • Kwon, Jung-Eon
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.2
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    • pp.1-10
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    • 2021
  • The purpose of this study is to explore a significant HPWS(High Performance Work System) model for the entertainment industry. HPWS is one of the most studied themes for managing human resources as well as a set of practices to elicit employees' commitment to an organization. Recently, the entertainment industry is growing rapidly, but it is difficult for entertainment firms to retain a stable profit unlike the manufacturing industry. This is because the performance of entertainment business tends to rely heavily on the capabilities and synergy of human resources. In order to suggest a systematic way to manage these, this research identified an effective HPWS model for entertainment business and provides a competitive advantage to entertainment firms, using ANP(Analytic Network Process). ANP is a multicriteria decision making technique that allows dependences and feedbacks among decision elements in the hierarchical or network structures in a holistic manner. The pairwise comparison data that prioritized the criteria of HPWS was collected from 28 team leaders in entertainment firms. According to our results, the most critical factor for HPWS in entertainment business is "employee involvement in decision-making." The sub-factors such as "open communication," "distributive decision-making," and "performance-driven reward" have a greater effect. These findings could provide implications for entertainment firms to determine which practices should be taken into account to accomplish HPWS.

Development of Chinese Cabbage Detection Algorithm Based on Drone Multi-spectral Image and Computer Vision Techniques (드론 다중분광영상과 컴퓨터 비전 기술을 이용한 배추 객체 탐지 알고리즘 개발)

  • Ryu, Jae-Hyun;Han, Jung-Gon;Ahn, Ho-yong;Na, Sang-Il;Lee, Byungmo;Lee, Kyung-do
    • Korean Journal of Remote Sensing
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    • v.38 no.5_1
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    • pp.535-543
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    • 2022
  • A drone is used to diagnose crop growth and to provide information through images in the agriculture field. In the case of using high spatial resolution drone images, growth information for each object can be produced. However, accurate object detection is required and adjacent objects should be efficiently classified. The purpose of this study is to develop a Chinese cabbage object detection algorithm using multispectral reflectance images observed from drone and computer vision techniques. Drone images were captured between 7 and 15 days after planting a Chinese cabbage from 2018 to 2020 years. The thresholds of object detection algorithm were set based on 2019 year, and the algorithm was evaluated based on images in 2018 and 2019 years. The vegetation area was classified using the characteristics of spectral reflectance. Then, morphology techniques such as dilatation, erosion, and image segmentation by considering the size of the object were applied to improve the object detection accuracy in the vegetation area. The precision of the developed object detection algorithm was over 95.19%, and the recall and accuracy were over 95.4% and 93.68%, respectively. The F1-Score of the algorithm was over 0.967 for 2 years. The location information about the center of the Chinese cabbage object extracted using the developed algorithm will be used as data to provide decision-making information during the growing season of crops.

A Study on the Lead(Pb) Shield Thickness per Electron Beam Energy in Radiotherapy (방사선 치료용 전자선의 에너지별 납(Pb) 차폐체 두께 측정)

  • Gha-Jung, Kim
    • Journal of the Korean Society of Radiology
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    • v.16 no.6
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    • pp.719-725
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    • 2022
  • This study aimed to measure, quantitatively evaluate, and set the criteria for the minimum lead(Pb) shield thickness per level of clinically applied electron beam energy. The lead shield thickness per electron beam energy was measured using the primary field 95% reduction based on the open field at the depth of maximum dose (dmax) and depth from the surface as the reference depth of tissue dose(10 mm). The measured values were 1.906 mmPb and 1.992 mmPb at the dmax and 10 mm, respectively, regarding the lead shield thickness for 6 MeV electron beam; 2.746 mmPb and 3.743 mmPb for 9 MeV electron beam, 3.718 mmPb and 6.093 mmPb for 12 MeV electron beam, 7.300 mmPb and 15.270 mmPb for 16 MeV electron beam, and 16.825 mmPb and 25.090 mmPb for 20 MeV electron beam. Consequently, a thicker lead shield was required if the measurement was at 10 mm. The required lead shield thickness was also higher than that of the theoretical formula for electron beams of ≥ 16 MeV.

A Study on the Evaluation of Radiation Safety in Opened-Ceiling-Facilities for Radiography Testing (천장 개방형 RT 사용시설의 방사선 안전성 평가 연구)

  • Sung-Hoe, Heo;Won-Seok, Park;Seung-Uk, Heo;Byung-In, Min
    • Journal of the Korean Society of Radiology
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    • v.16 no.6
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    • pp.741-749
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    • 2022
  • Radiography-Testing that verify the quality of welding structures without destruction are overwhelmingly used in industries, but many safety precautions are required as radiation is used. The workers for Radiography-Testing perform the inspection by moving the Iridium-192 radiation source embedded in the transport container of the gamma-ray irradiator within or outside the facility. The general facility is completely blocked about radiation from the outside with thick concrete, but if it is difficult for worker to handle object of inspection, facilities ceiling can be opened. A general facility may be constructed using a theoretical dose evaluation method because all exterior facilities are blocked, but if the ceiling is open, it is not appropriate to evaluate radiation safety with a simple theoretical calculation method due to the skyshine effect. Therefore, in this study, the radiation safety of the facility was evaluated in the actual field through an ion chamber survey-meter and an accumulated dose-meter called as OSLD, and the actual evaluation environment was modeled and evaluated using the Monte Carlo simulation code as FLUKA. According to the direction of the irradiation, the radiation dose at the facility boundary was difficult to meet the standards set by the regulatory authority, and radiation safety could be secured through additional methods. In addition, it was confirmed that the simulation results using the Iridium-192 source were valid evaluation with the actual measured results.

A Study on the Method of Creating a Safety Vulnerable Class Distribution Diagram for Non-Structural Countermeasures in the Comprehensive Natural Disaster Reduction Plan (자연재해저감종합계획 비구조적 대책의 안전취약계층도 작성방안에 관한 연구)

  • Doo Hee Kim;In Jae Song;Byung-Sik Kim
    • Journal of Korean Society of Disaster and Security
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    • v.16 no.1
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    • pp.1-11
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    • 2023
  • The comprehensive natural disaster reduction plan, the highest plan in the disaster prevention field, was implemented by local governments. second plan is currently being formulated. In order to minimize human and property damage, structural and non-structural measures for each of the nine disaster types are established and implemented for 10 years. Structural measures are based on engineering and quantitative analysis, and the criteria for setting reduction measures are clear. Non-structural measures, however, currently lack the set criteria. the basic disaster and safety management law included the safety vulnerable class in 2018. Currently, the safety vulnerable class of the detailed establishment criteria of the comprehensive natural disaster reduction plan is being established, including children, the elderly, and the disabled. However, due to the lack of data securing and database construction by local governments, it is difficult to prepare a location map for establishing reduction measures for the safety vulnerable. Therefore, in this study, OPEN API data of the safety vulnerable class were collected and statistical information and GIS of SGIS information services were used. The distribution diagram of the safety vulnerable class in Samcheok, Gangwon-do, which is a sample area, and the distribution diagram of the safety vulnerable class in units of the output area (OA) in Geundeok-myeon were prepared.