Duk-Ho Chung

Development and Application of Teaching Materials for Geological Fieldwork in Jeokbyeokgang Area, Gyeokpo, Byeonsan, Korea

This study is to develop teaching materials for the geological fieldwork of Jeokbyeokgang area located in the national park of the Byeonsan-bando National Park, Buangun, Jeonbuk, Korea. The developed teaching materials are used in middle school science to effectively teach the fieldwork of the area. The sedimentary succession of Jeokbyeokgang area in the Cretaceous age, Mesozoic, represents the large-scale and distinctive sedimentary structures on sea cliffs, which are worth developing as teaching materials for the earth science fieldwork. The area of Jeokbyeokgang also comprises various geological structures related to the advanced learning programs as well as those within the curriculum of earth science in middle school level. A five-step fieldwork model was applied to 20 students in middle school earth science. This study quantitatively analyzed students` responses to the process of the fieldwork activity. Results indicated that the fieldwork activity using the developed teaching materials was effective in helping the students to improve their self-directed learning and practical understanding of earth science.

A Communication Structure of Science Gifted Students Based on the Social Network Analysis

The purpose of this study was to investigate the communication structures that science gifted students used in small group activities, and to examine the relationship between communication styles and their achievement level. Eight small groups,5 members in each, participated in small group activities, in which they discussed how to calculate the average density of the earth. The communication structures and the achievement level presented in the group activities were analyzed using Pajek, Ucinet 6.0. As a result, we classified the communication styles of science gifted students into monopolistic type and co-ownership type according to the degree of dispersion of the interaction. We also classified it into type, type, type, and type based on the density and network centralization of interaction. The achievement levels of gifted students in their group work were affected by the density of interaction and the network centralization in small group activities, not by the dispersion of interaction among the members of the groups. Therefore, we recommend that teachers make the communication relevant to solving problem when they utilize a small group activity in science teaching.

A Biogeochemical Study on the Heavy Metal Leaching from Coal Fly Ash Disposed by Dangjin Fire Plant in the Coastal Environment

It is known that coal-derived fly ashes have the unique chemical composition and mineralogical characteristics. Since iron oxides in coal fly ash are enriched with heavy metals, the subsurface media including soils, underground water, and sea water are highly likely contaminated with heavy metals when the heavy metals are leached from fly ashes by water-fly ash interactions. The purpose of this study was to investigate how indigenous bacteria affect heavy metal leaching and mineralogy in fly ash slurry during the fly ash-seawater interactions in the ash pond located in Dangjin seashore, Korea. The average pH of ash pond seawater was 8.97 in nature. Geochemical data showed that microbial activity sharply increased after the 7th day of the 60-day course batch experiments. Compared with other samples including autoclaved and natural samples, was likely to decrease considerably in the fly ash slurry samples when glucose was added to stimulate the microbial activity. Geochemical data including Eh/pH, alkalinity, and major and trace elements showed that the bacteria not only immobilize metals from the ash pond by facilitating the chemical reaction with Mn, Fe, and Zn but may also be able to play an important role in sequestration of carbon dioxide by carbonate mineral precipitation.

Differences of Perception on Giftedness between Homeroom Teachers and Teachers of The Gifted

The purpose of this study is to investigate the differences of perception on giftedness between homeroom teachers and teachers of the gifted. The data was collected from 13 homeroom teachers and 8 teachers of gifted students. It was analyzed using recommendation letters, and shorthand notes about giftedness. The results of the study were as follows: most homeroom teachers used awards, learning attitude, presentation of self and school achievements for defined giftedness and preferred an exemplary student with task commitment but often overlooked motivation. The teachers of the gifted preferred motivation and self-satisfaction but not other social and affective characteristics. Also homeroom teachers thought that education condition is important, while the teachers of the gifted believed it was not an all important element. These differences will hurt the credibility in the selection or gifted students because homeroom teachers and teachers of the gifted use different words and expressions in their assessments of the same students. Therefore, I believe more needs to be done to encourage homeroom teachers to better understand gifted children through training programs.

A Study on the Problem Solving Styles according to Left/Right Brain Preference of Earth Science Gifted Students

This study is to investigate the problem solving styles according to the left /right brain preference among earth science gifted students. We took the R/LCT and the test of BPI to investigate the brain preference of earth science gifted students (N

A Study of Gifted Students` Peer Relationship in an Elementary School`s General and Gifted Classes

Peer relationships in young students` communities are one of the important factors influencing the cognitive and affective domains of learning. Moreover, students who join the special program for gifted students possess differential peer relationships from the students in general classes. This study aims to explore the differences of 5th grade five science-gifted students` peer relationships between students in special classes for gifted students and general classes. Five students in the special program for gifted students, managed by the Office of Education in a southern city, participated in this study. Social network analyses were utilized to explore participants` peer relationships; the students` homeroom teacher was interviewed to explore the contextual and in-depth characteristics of gifted students` peer relationships. The results illustrated four cases of peer relationships: (1) smart loner (2) my study mate (3) I`m the best in my class, and (4) a good friend anywhere. This study identified that the gifted students possessed diverse peer relationships in both the special program and general classroom. In addition, this study suggests that the program for gifted students needs to be specially designed based on the gifted students` peer relationship.

A Perception of Beginning Earth Science Teachers on Porphyritic Texture

This study is to explore the Pedagogical Content Knowledge of beginning earth science teachers about the porphyritic texture of igneous rocks, and to suggest the teaching device that can prevent a trial and error of students in earth science instruction. We developed an interview guideline concerned with basic perception on the porphyritic texture, formation condition and formation process of porphyritic rocks, teaching and learning on porphyritic rocks for it. And data was collected from 5 beginning earth science teachers (3 high schools, 2 middle schools) through a group discussion method. In result, despite the porphyritic texture can be found at hypabyssal rocks as well as volcano rocks and plutonic rocks, most beginning earth science teachers cognized that it could be found at hypabyssal rocks only by focusing the formation depth of hypabyssal rocks. Also, the formation of porphyritic texture should be considered the factors such as cooling rate, nucleation density, growth rate, growth time, etc. However they mainly reflected the formation temperature and growth rate as its parameter. Participants have wrongly perceived that a phenocryst necessarily differs from a groundmass on chemical composition. And they are inclined to discriminate phenocryst from groundmass through their chemical differences, instead of grain size.

The Effects of Astronomical Animation Module on Earth Science Gifted Students's Conceptual Change of Diurnal Motion

The purpose of this study is to investigate the effects of astronomical animation module on students` conceptual change regarding the concepts of diurnal motion of stars. Four students participated in this study, who never learned about the diurnal motion of stars. An animation module was developed by using Flash MX to readily understand the concept of space. In addition, we inserted a teacher`s voice with supplementary materials into the animation module to help students learn individually. The animation module was comprised of the movement of the Earth, the Moon and the planet. The earth science gifted students` preconception on diurnal motion of stars was analyzed with pre-test using questionnaires and interviews. After the instruction with animation module, the effect of conceptual change was examined by comparing pre and post-test. The results indicated that three students correctly presented about the motion of the star by all directions in middle latitude. Four students showed their understanding that stars travelled straight in all directions. Finally, all of four students whose preconceptions were that the star rotated perpendicularly showed the conceptual change of diurnal motion that the star traveled diagonally.

A Comparison of the Learning Semantic Network about Sedimentary Environment between Science Gifted Students and Non-Gifted Students through Geological Field Trips

The purpose of this study was to compare the difference of semantic network about sedimentary environment between science gifted students and non-gifted students through field trip. The fifteen high school science gifted students and non-gifted students were participated in the field trip for this study. The geological field trip was performed in Chaseokgang, which suitable learning place for sedimentary environments. Data included field trip observation and students` inquiry activity reports. The inquiry activity reports were analyzed using the semantic network analysis method. The results of this study were as follows: First, the semantic network of science gifted students was larger and complex structures than that of the non-gifted students. Second, science gifted students were interpreted that changes of sedimentary environment was connected with the sorting and the roundness. On the other hand, semantic network of non-gifted students were become fragmented because they were not interpreted sedimentary environment related to scientific concepts.

A Biogeochemical Study of Heavy Metal Leaching from Coal Fly Ash Disposed in Yeongdong Coal-Fired Power Plant

Fly ashes derived from coal fired power plants have unique chemical and mineralogical characteristics. The objective of this research was to study how indigenous bacteria affected heavy metal leaching in fly ash slurry during the fly ash-seawater interactions in the ash pond located in Yeongdong seashore, Korea. The in-situ pH of ash pond seawater was 6.3-8.5. For this study, three sites of the ash pond were chosen to collect a sample of fly ash slurry. Three samples that had a mix of fly ash (0.4 L) and seawater (1.6 L) were collected at each site. First sample was autoclaved (120o C, 2.5 atm), second one was inoculated with glucose to stimulate the microbial activity, and the last sample was kept in the natural condition. Compared with other samples including autoclaved and natural samples, the glucose added sample showed sharp increase in its alkalinity after 15 days, cation concentration change such as Ca, Mg, and K seemed to increase in early stage, and then decrease 15 days later in slurry solution of glucose added sample, and a possibly considerable decrease in SO 4 2� in the fly ash slurry samples when glucose was added to stimulate the microbial activity. Geochemical data of this study is likely to be related to the activity of bacteria at the ash pond. The result may be used to understand about the characteristic of bacteria.