The purpose of the study was to investigate how the use of graphing calculators influence on forming students' mathematical concept of algebra, students' mathematical connection, and attitude toward mathematics. First, graphing calculators give instant feedback to students as they make students compare their written answers with the results, which helps students learn equations and linear inequalities for themselves. In respect of quadratic inequalities they help students to correct wrong concepts and understand fundamental concepts, and with regard to functions students can draw graphs more easily using graphing calculators, which means that the difficulty of drawing graphs can not be hindrance to student's learning functions. Moreover students could understand functions intuitively by using graphing calculators and explored math problems volunteerly. As a result, students were able to perceive faster the concepts of functions that they considered difficult and remain the concepts in their mind for a long time. Second, most of students could not think of connection among equations, equalities and functions. However, they could understand the connection among equations, equalities and functions more easily. Additionally students could focus on changing the real life into the algebraic expression by modeling without the fear of calculating, which made students relieve the burden of calculating and realize the usefulness of mathematics through the experience of solving the real-life problems. Third, we identified the change of six students' attitude through preliminary and an ex post facto attitude test. Five of six students came to have positive attitude toward mathematics, but only one student came to have negative attitude. However, all of the students showed positive attitude toward using graphing calculators in math class. That's because they could have more interest in mathematics by the strengthened and visualization of graphing calculators which helped them understand difficult algebraic concepts, which gave them a sense of achievement. Also, students could relieve the burden of calculating and have confidence. In a conclusion, using graphing calculators in algebra and function class has many advantages : formulating mathematics concepts, mathematical connection, and enhancing positive attitude toward mathematics. Therefore we need more research of the effect of using calculators, practical classroom materials, instruction models and assessment tools for graphing calculators. Lastly We need to make the classroom environment more adequate for using graphing calculators in math classes.
Objectives: In a number of simulated night shift studies, timed exposure to bright light improves sleep quality and work performance. We evaluated the effect of bright light on adaptation to night shift work with a field study. Methods: Five female nurses working shifts at Korea University Hospital were recruited for participation in this study. We investigated two series of six consecutive shift rotations comprising three day and three night shifts, using wrist Actigraphy, the Stanford Sleepiness Scale, Visual-analogue scales, STIM and tympanic membrane temperature for daytime sleep quality, alertness, subjective feeling, attention performance, and temperature rhythm. The subjects were exposed to bright light (2,500 lux) from 24:00 to 04:00 a.m. on three consecutive night shifts during the second series, whereas they worked under normal lightening (650 lux) conditions during the first series. Results: Actigraphic assessment of daytime sleep showed no significant difference between the first and third night shift in both baseline and light exposure phase. The mean lowest temperature shifted earlier during baseline phase but not during the light exposure phase. Also, the score for subjective feelings of depression, anxiety, physical discomfort and sleepiness was significantly higher in the third night shift than the first during baseline phase but not during the light exposure phase. Attention and attention switching ability was significantly improved in the third night shift compared to the first night during the light exposure phase but there were no significant changes during the baseline phase. Conclusion: This result suggests that there were no significant differences between the two phases in measures of quality of daytime sleep, but subjective feelings, attention and alertness were enhanced during light exposure. Although some placebo effects and learning effects might influence this result, bright light exposure between midnight and 4:00 a.m. may improve adaptation to night shift. In future, further controlled studies with a larger sample size, including melatonin measurement, are needed for real shift workers.
The purpose of this study is to suggest the basic data in order to examine and perform the plan for activating the team teaching between industry-educational adjunct teachers and vocational teachers in technical high school. The research results are as follows. First, It is found that both teacher groups acknowledge the necessity of the team teaching, but vocational teachers are less likely to recognize the necessity than industry-educational adjunct teachers. Second, In the preparation of team teaching, both two groups of the teachers believe that the preliminary interchange and training between them are to be highly supportive for the activities expected to help teachers. Therefore, it is necessary to have opportunity of communication and narrow the difference of opinions between them by promoting the deep interest about applicable field and sharing the mutual idea between the teachers in the preparation of team teaching. Third, And the two groups recognize that the cooperation and joint establishment of design of team teaching and the individual process or joint progress of class activity are desirable for the proper design of team teaching. Therefore, it is necessary to establish the class environment for the interaction between teachers and students through not only the reciprocal activities between teachers but the interest class by systematically preparing the class design and role division clearly. Fourth, In the practice of team teaching, the two groups believe that the teaching activities can be usually divided and progressed, but it is desirable to work together in the related contents. The vocational teachers recognize that it is necessary to actively interact with students by connecting with the case of industry field. On the other side, industry-educational adjunct teachers think that the learning contents should be selected and organized according to the interests of students by associating with the case of industry field. Fifth, And two groups of teachers recognize that it is desirable to evaluate the grade by reflecting on the assessment by vocational teachers(50%), industry-educational adjunct teachers(50%).
Kim, Eun-Suk;Park, Kwang-Seo;Oh, Chang-Ho;Kim, Dong-Jin;Park, Kuk-Tae
Journal of the Korean Chemical Society
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v.48
no.6
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pp.645-653
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2004
The purpose of this study was to compare and analyze the cognitive levels of 11th grade students and those required in high school chemistry I textbooks standardized by the 7th national education curriculum. For this study, the cognitive development stages of 456 11th grade students were surveyed using short-version GALT (group assessment of logical thinking). Furthermore, 15 basic concepts were extracted from the contents on water and air, 2 units in chemistry I order to analyze the cognitive levels necessary for understanding high school textbooks, using CAT (curriculum analysis taxonomy). The results showed that 52.5% of the surveyed 11th grade students reached the formal operational level, 28.3% transitional levels, and 19.5% concrete operational levels. 68.9% of the academic high school students and 6.6% of the technical high school students reached the formal operational levels, and the ratio of formation was very different in each logics. As a result of the analyzing the cognitive levels needed for understanding chemistry I textbook contents, in spite of a change in national education curriculum, there were no great change in cognitive levels required by scientific concept except some inquiry activities. The cognitive levels in high school chemistry I textbooks by the 7th national education curriculum appeared higher than the cognitive levels of 11th grade student, but cognitive levels of inquiry activities were similar to the cognitive levels of the students. Chemistry teachers thought of chemistry I textbooks by the 7th national education curriculum as desirable because scientific concepts were reduced and a lot of real life materials were adapted. However, they pointed out a problem of difference in contents levels compared with chemistry I textbooks because scientific concepts were greatly reduced in chemistry I textbooks. The cognitive levels required in chemistry I textbooks still appeared higher than those of the students. Consequently, various teaching and learning methods and materials will have to be developed to be suitable for the students' cognitive levels.
The purposes of this study are to examine the effects of learning, which was applied TRIZ's 40 inventive principles, on the improvement of learners' creativity and to offer basic information that would be necessary to study on Inventive Education in Technology Education. In order to achieve the purposes, objects were divided into two groups, experiment group(74 students) and control group(67 students), who were from B Middle school in Daejeon. Creativity Self-Assessment and Student Inventive Rating Scale were used as tools for research so that we could find the homogeneity in two groups. An applied design method was nonequivalent control group pretest-posttest design. This study was performed for 2 hours on the 1st and the 3rd Saturday in every month from the 3rd week of March, 2006 to the 3rd of July of 2006, and total researching period was 9 weeks. In that time, the students were required to learn 40 inventive principles. The results from this study are as below. (1) Applying TRIZ's 40 inventive principles had a positive effect on students' CQ(creative quotient), as influencing on the subordinate factors of creativity, such as, originality, germinal, trasformational, value, attraction, expressive power and organic systemicity. However it didn't have any effect on adequateness, properness, merit, complex and elegance. (2) Applying TRIZ's 40 inventive principles had a significant effect neither on CQ by sex, nor on the subordinate factors of creativity, except for originality and expressive power. Based on the results of the experiment, below suggestions were made to promote the application of TRIZ's 40 inventive principles to Technology Education. (1) Although this study was performed by using development activities, it is necessary to study more systemically to apply 40 inventive principles to regular subject in Technology Education. (2) As creativity was very important in Technology Education, there should be studies on the various types of inventive principles and techniques for Inventive Education in Technology Education.
Kim, Yuran;Jeon, Jaedon;Eom, Jooyoung;Lee, Hyonyong
Journal of the Korean earth science society
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v.41
no.1
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pp.75-91
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2020
The purposes of this study are 1) to develop a pre-education program for teaching the basic concepts of systems thinking and STEAM program based on systems thinking and 2) to investigate the effects of the program on middle school students' systems thinking. The subjects were 4 seventh-graders and 4 ninth-graders in a middle school located in the province of Gyeongsangbuk-do. Data related to students' systems thinking was analyzed using the rubrics developed by Hung(2008). The results were reviewed by experts to verify the validity of the rubrics and the reliability of students' system thinking. In addition, the data analyzed with the rubrics, students' awareness of systems thinking, word associations, causal maps and interviews were systematically analyzed to investigate the effects of the program on students' systems thinking. The findings of this study were as follows: First, a pre-education program and teachers' guidebook for teaching and learning the concept of systems thinking and causal maps were developed. The pre-education program consisted of familiar TV entertainment program-Infinite Challenge (Muhandojeon)-with a theme of Global Warming. Second, a STEAM education program based on systems thinking which was composed of 5 steps: Analysis-Design-Build-Assessment-Systems thinking. The major theme of the program was an air extinguisher. The developed STEAM education program had positive effects on improving middle school students' systems thinking abilities such as understanding systems, relations within a system and system generalization. Therefore, it was concluded that the STEAM program could be instrumental for cultivating students' STEAM literacy with improved systems thinking.
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.
Ha, Minsu;Park, HyunJu;Kim, Yong-Jin;Kang, Nam-Hwa;Oh, Phil Seok;Kim, Mi-Jum;Min, Jae-Sik;Lee, Yoonhyeong;Han, Hyo-Jeong;Kim, Moogyeong;Ko, Sung-Woo;Son, Mi-Hyun
Journal of The Korean Association For Science Education
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v.38
no.4
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pp.495-504
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2018
This study was conducted to develop items to measure scientific core competency based on statements of scientific core competencies presented in the 2015 revised national science curriculum and to identify the validity and reliability of the newly developed items. Based on the explanations of scientific reasoning, scientific inquiry ability, scientific problem-solving ability, scientific communication ability, participation/lifelong learning in science presented in the 2015 revised national science curriculum, 25 items were developed by five science education experts. To explore the validity and reliability of the developed items, data were collected from 11,348 students in elementary, middle, and high schools nationwide. The content validity, substantive validity, the internal structure validity, and generalization validity proposed by Messick (1995) were examined by various statistical tests. The results of the MNSQ analysis showed that there were no nonconformity in the 25 items. The confirmatory factor analysis using the structural equation modeling revealed that the five-factor model was a suitable model. The differential item functioning analyses by gender and school level revealed that the nonconformity DIF value was found in only two out of 175 cases. The results of the multivariate analysis of variance by gender and school level showed significant differences of test scores between schools and genders, and the interaction effect was also significant. The assessment items of science core competency based on the 2015 revised national science curriculum are valid from a psychometric point of view and can be used in the science education field.
The Journal of the Convergence on Culture Technology
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v.6
no.3
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pp.1-8
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2020
EuiJae Hu BaekRyun is a symbol of Honam Namjonghwa and is respected as a teacher of Honam culture. He is from JinDo and is a relative of Sochi Heo Ryun and a disciple of Misan Heo Hyeong. The spirit of traditional Namjongghwa and the dignity of painting faithful to its technique have been obtained by themselves, and have made it his own. EuiJae organized a 'Yeonjinhoe' in Gwangju to raise his students. After liberation, a house was built under Mudeungsan Mountain. And showed another aspect as a social educator who emphasized and practiced national spirit while being a tea ceremony man. He excelled in Chinese poetry and painting theory, and expressed a unique field in calligraphy. especially worked as an artist good at poetry, caligraphy, and painting. EuiJae showed exceptional talent, especially in landscape painting. His tendency to paint was to follow Ye Chan's technique of drawing with a dry brush, placing importance on the energy of learning, and constantly trying new experiments with the technique of gisaeng. The world of EuiJae's works can be divided into three periods, based on the signature using the trend of painting or the change of perspective pursued, the era of EuiJae, the era of EuiJaeSanin, and the era of EuiDoin, which had a tendency of independent painting. EuiJae's contribution surpassed the artistic historical assessment that he had formed a big stem for the authentic Namjongghwa of Korean painting culture, which was part of Oriental painting. And recognizing that he was a fundamental teacher connecting modern times through the actual scenery based on NamDohwa's universal spirit and regional characteristics and the creative succession of emotions, he should inherit his passion for artistic spirit and tradition and experimental spirit.
This study was intended to determine PCK of the middle school science teachers on Mendelian genetics and factors influenced to form their PCKs. Two science teachers with biology major with a teaching experience over 5 years were chosen as the subject. Data were collected by class observation, semi-structured interview, teacher questionnaire survey, Content Representation and Pedagogical and Professional-experience Repertoire. The collected data were analyzed based on Magnusson's PCK for science teaching consisting of five components: (a) the orientation toward teaching science, (b) the knowledge of science curriculum, (c) the knowledge of students' understanding, (d) the knowledge of assessment, and (e) the knowledge and belief in the instructional strategies to teach science. Teachers could have the orientation toward teaching science served as an assisting role to support students' abilities. Both subject teachers seemed to focus on giving lectures. Their efforts to improve students' exploration methods and abilities were not expressed enough in their real classes and they found that students struggled to understand Mendelian genetics. Therefore, they should have explained them in an easier way and worked harder to make their students understood accurately and applied basic and advanced concepts of Mendelian genetics. They found students' preconception and misconception regarding Mendelian genetics and wished to enhance their learning effects by various teaching strategies such as correcting misconception, adding the history of science and simply assessing students' affirmative domains. It was also found that factors influenced to form PCK regarding Mendelian genetics by both teachers were as follows: teacher's personality and endeavor, textbooks and guidance books, schools and their circumstances, teaching experience, experience as a learner, interaction with their colleagues, and university curriculum. Both teachers said that it was important for teachers to make every efforts to give better classes.
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