• Journal of the Korean earth science society
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• v.30 no.5
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• pp.671-681
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• 2009

In the equilibrium theory of tides by Newton, tide on the Earth is a phenomenon driven by differential gravity contributed both by the Sun and the Moon. Due to the direct link of the generic tidal effect to the oceanic tides, college students in the earth science education department are exposed to this theory through oceanography lectures as well as astronomy lectures. Common oceanography textbooks adopt a non-inertial reference frame fixed to the Earth in which the fictitious, centrifugal force appears. This has a potential risk to provide misconceptions among students in various aspects including the followings: 1) this is how Newton originally derived the equilibrium theory of tides, and 2) the tide is a phenomenon appearing only in rotating systems. We show that in astronomy, a much simpler description, which employs the inertial frame, is generally used to explain tides and thus causes less confusion. We argue that the description used in astronomy is preferable both in the viewpoints of simplicity and ease of interpretation. Moreover, on a historical basis, an inertial frame was adopted by Newton in Principia to explain tides. Thus, the description used in astronomy is consistent with Newton's original approach. We also present various astrophysical tides which do not comply with the concept of centrifugal force in general. We therefore argue that the description used in oceanography should be compensated by that in astronomy, due to its complexity, historical inconsistency and limited applicability.

• Journal of the Korean earth science society
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• v.21 no.6
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• pp.683-694
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• 2000

Abstrace: The palaeodepositional environment and age of the Cretaceous Hampyeong Basin (southwestern Korea) are reassessed based on new geochemical, lithological, sedimentological, and palaeobotanical data. Results indicate that the Hampyeong Basin was a tectonically active basin comprising predominantly fluvial and lacustrine sediments. Four distinctive facies types have been identified (acidic tuff, black shales/sandstones, red beds, intermediate tuff with tuffaceous conglomerate) and these reflect periods of significant environmental change within the basin and its neighbouring terrains. Volcanism driven by tectonic events provides a source for much of the sediment. The sedimentary sequences compare well with those in the neighbouring Haenam Basin. Sediments of volcanic origin are similar to those of the Neungju Formation of the Yuchon Group. The widespread occurrence of black shales is indicative of extended periods of deposition under anoxic conditions. Measurements of total organic carbon show that the values for the black shales (0.81% to 1.75%) are the average for petroleum source shales. Fossil plants occurred in the black shales and sandstones. The occurrence of platanoid leaves places these sediments in Oishi's angiosperm series, which is consistent with an Aptian/Albian or younger age.

• Journal of the Korean earth science society
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• v.44 no.4
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• pp.318-330
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• 2023

This study aimed to verify the validity of a measurement tool for Vietnamese high school students' systems thinking abilities. Two quantitative assessment tools, the Systems Thinking Measuring Instrument (Lee et al., 2013) and the Systems Thinking Scale (Dolansky et al., 2020), were used to measure students' systems thinking after translation into Vietnamese. As a result, it was revealed that Cronbach-α for each tool (i.e., STMI and STS) was .917 and .950, respectively, indicating high reliability for both. To validate the construct validity of the translated questionnaire, exploratory factor analysis was performed using SPSS 26.0, and confirmatory factor analysis was performed using AMOS 21.0. For concurrent validity, correlation analysis using structural equation modeling was performed to validate the translated questionnaire. Exploratory factor analysis revealed that 10 items from the STMI and 12 items from the STS loaded on the intended factors and appropriate factor loading values were obtained. For confirmatory factor analysis, a structural equation model organized with 10 items from the STMI and 12 items from the STS was used. The result of this showed that the convergent validity values of the model were all appropriate, and the model fit indices were analyzed to be χ²/df of 1.892, CFI of .928, TLI of .919, SRMR of .047, and RMSEA of .063, indicating that the model consisting of the 22 items of the two questionnaires was appropriate. Analysis of the concurrent validity of the two tools indicated a high correlation coefficient (.903) and high correlation (.571-.846) among the subfactors. In conclusion, both the STMI and STS are valid quantitative measures of systems thinking, and it can be inferred that the systems thinking of Vietnamese high-school students can be quantitatively measured using the 22 items identified in our analysis. Using the tool validated in this study with other tools (e.g., qualitative assessment) can help accurately measure Vietnamese high school students' systems thinking abilities. Furthermore, these tools can be used to collect evidence and support effective education in ODA projects and volunteer programs.

• Journal of the Korean earth science society
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• v.40 no.5
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• pp.476-486
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• 2019

This study examines the controlling role of synoptic disturbances on $PM_{10}$ spring variability in the Korean Peninsula by using empirical orthogonal function (EOF) and back trajectory analyses. Three leading EOF modes are identified, and a lead-lag analysis suggests that $PM_{10}$ variabilities be closely related to the synoptic weather systems. The first EOF shows the spatially homogeneous distribution of $PM_{10}$, which is influenced by travelling anticyclonic disturbance with negative precipitation and descending motion. The second and third modes exhibit the dipole structures of $PM_{10}$, being associated with propagating cyclones. Furthermore, the back-trajectory analysis suggests that the transport of pollutants by anomalous winds associated with synoptic disturbances also contribute to the altered $PM_{10}$ concentration. Hence, a substantial synoptic control should be considered in order to fully understand the $PM_{10}$ spatiotemporal variability.

• Journal of Korean Elementary Science Education
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• v.21 no.1
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• pp.43-59
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• 2002

There has been a long debate whether the Sun revolves the Earth or the Earth revolves the Sun. Also, students are very interested in the solar systems, which means the entire system of planets, satellites, minor planets, comets, and meteoroids that orbit the sun. However, students are not sure about them. New models which enhance teaming about them are strongly needed. This study is intended to develop the new models on the solar systems and to investigate how the preservice elementary teachers' concepts are affected by them. Subjects are 20 preservice elementary teachers, One instrument including 11 items is used. Data are collected before using the new models and after using them through the tests. As a result, learning through the new models has a positive effects on the preservice elementary teachers' concepts on the solar system.

• Journal of the Korean earth science society
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• v.36 no.6
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• pp.591-608
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• 2015

The purpose of this study was to analyze system thinking revealed in science teachers' teaching practices of middle school astronomy classes. Astronomy lessons were video-taped from four eighth grade science teachers. The video recordings were all transcribed and analyzed by employing a framework for systems thinking analysis after modifying an existing frame of hierarchial structure used in relevant previous studies. In addition, four participants were interviewed in order to uncover their orientation toward teaching using video stimulated recall method. Findings are as follows: All participating teachers were not able to employ the four levels of system thinking appropriately and only utilized the low level of systems thinking. They also demonstrated teacher-centered practices for employing system thinking despite their student-centered orientation toward teaching. The main reason for these results may be that teachers focused more on spatial thinking, than on system thinking as well as the lack of teacher's knowledge about the content and formative assessment of non-earth science teachers. Implications on how to effectively employ the system thinking in astronomy class are discussed in this paper.

• Journal of the Korean earth science society
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• v.23 no.4
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• pp.299-308
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• 2002

While the 7th national education curriculum is gradually proceeding, science education tries various teaching-learning method for integration in science education. The first purpose of this study is to investigate Earth Systems Education(ESE), which is approaching method to integrate science education, especially in its focus on planet Earth. Also, the second purpose is to know what the reactions of students are obtained after 'The Global Climate Game' in ESE active learning program is applied to the field. The results of this study are as follows; ESE is to propose the integrated approaching method of searching for natures and ESE teaching-learning method is to try to overcome fixed conventional teaching-learning method focus on the text book, and practical application of ESE teaching-learning method is that we can develope the student-emphasized instructional program through the discussional cooperation-teaming models, role-play instructional models. In this study, 'The Global Climate Game' found that was suitable of understanding about relating of atmosphere, hydrosphere, lithosphere and biosphere composing Earth System. Reaction of most students for ESE was showed a positive change of aspect affective region and ESE active learning program is more efficient to improve schoolwork achivement and students positive attitude toward science subject than conventional teaching-learning method. Thus if ESE active learning program is applied for a long time, the general positive attitude of students concerning science will be increased, and then the students is expected to extend the ability of application of science in their life.

• 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.

• 한국지구과학회:학술대회논문집
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• 2003.09a
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• pp.3-10
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• 2003

Curriculum reform has been a significant emphasis for most of countries all over the world for the past few years. It was the first time for Taiwan to develop a new Science and Life Technology curriculum Standards (SaLTS) for grades 1 through 9 compulsory educations. The SaLTS features integrated science content with the aim at motivating students to learn science and encouraging students to apply science to their everyday life, which is practically well aligned with the philosophical essence and foundations of Earth Systems Education (ESE). This paper calls attention to the importance of the inclusion of ESE into the forthcoming science curricula of Taiwan and worldwide and provides some exemplary ESE-inspired curriculum and instructional modules that have been successfully implemented in the secondary schools of Taiwan. Hopefully, this paper can shed some lights on the future development of the ESE-based science curricula, instructional modules, and teacher preparation programs.

• Journal of the Korean earth science society
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• v.40 no.5
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• pp.487-501
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• 2019

In this study, steric height variability in the East Asian Seas (EAS) has been analyzed by using ocean reanalysis intercomparison project (ORA-IP) data. Results show that there are significant correlations between ocean reanalysis and satellite data except the phase of annual cycle and interannual signals of the Yellow Sea. Reanalysis ensemble derived from 15-different assimilation systems depicts higher correlation (0.706) than objective analysis ensemble (0.296) in the EAS. This correlation coefficient is also much higher than that of the global ocean (0.441). For the long-term variability of the thermosteric sea level during 1993-2010, a significant warming trend is found in the East/Japan Sea, while cooling trend is shown around the Kuroshio extension area. For the halosteric sea level, a dominant freshening trend is found in the EAS. However, below 300 m depth around this area, the signal-to-noise ratio of the linear trend is generally less than one, which is related to the low density of observation data.