• Journal of The Korean Association For Science Education
• /
• v.36 no.5
• /
• pp.739-756
• /
• 2016

The purpose of the study is to reflect on 'myself' as a teacher educator of college of education in depth and to improve my instruction through self-study with three critical collaborators. 17 pre-service science teachers and I have participated in this study of a teacher educator's course since March 2016 after the preliminary practice in 2015. The video recorded the course for 11 weeks with about 40 hours of lessons. The data source also included teacher educator's reflective journals, lecture evaluations, online boards and so on. Questionnaires were distributed and answered both at the beginning and at the end of the course and pre-service teachers wrote their reflective journals. Four of them were in the focus group interviews. During the course, the weekly group meeting of critical collaborators analyzed the emerging issues based on the lesson clips and teacher educator's reflective journals with discussion for the course innovation. Four phases were revealed in the process and for the purpose of the course such as exploration, conflicts, challenges, and changes. The results showed that first, we identified tensions among the teacher educator's multiple identities as a lecturer, a faculty member, and a researcher. Second, there were differences between goals of teacher educator and pre-service teachers in the course, and this obstructed the success of the course sometimes. Third, these practices led to explore balanced alternative views and interpretations of the problem by critical views and to expand and improve our teaching practice and thinking. In addition, the self-study with critical collaborators helped to bring conflicts and issues below my practice to light for collaborative reflection and it gave a chance to understand ourselves as teacher educators in different ways.

• Journal of the Korean earth science society
• /
• v.39 no.6
• /
• pp.519-532
• /
• 2018

We investigated the effect of galactic plane toward molecular motion and kinematics in the northern filament (NF) of Orion Molecular Clouds Complex (OMC) using $^{12}CO$ (J=1-0) line. Observed data were from three areas including NF1, NF2, and NF3 in far-out order from galactic plane, for a total 270 hours by Seoul National University Radio Astronomy Observatory (SRAO) 6m telescope, with 2arcmin spatial resolution. galactic plane and OMC NF were connected to each other along the magnetic field at a density of 3% for $^{12}CO$ (J=2-1) and 9% for the case of dust. $^{12}CO$ (J=1-0), $^{12}CO$ (J=2-1), and interstellar dusts were distributed uniformly in NF3, but only in certain regions with relatively high density in NF1 and NF2. NF showed a single structure, partial shrinking motion in NF1, and rotational motion at the bottom of NF2, and spiral rotation associated with magnetic field only in NF3. The position-velocity analysis showed that the materials including $^{12}CO$ (J=1-0) could flow toward galactic plane along NF2 and NF3. However, there was no clear cause for the material to flow toward galactic plane in this result. Further detailed observation for rotational motion at the top of NF1 and NF2 might help to confirm it.

• Journal of The Korean Association For Science Education
• /
• v.41 no.2
• /
• pp.145-154
• /
• 2021

This study aims to investigate teachers' perceptions of the composition of high school science elective courses ahead of the 2022 curriculum revision, and to derive implications for the organization of the 2022 revised science curriculum in preparation for the full implementation of the high school credit system. To this end, a survey was conducted by randomly sampling high schools across the country. A total of 192 science teachers responded to the questionnaire. In addition, 12 high school science teachers were selected as a focus group, and in-depth interviews were conducted to investigate opinions on the restructuring of elective courses in science. Main research results include 129 (67.2%) science teachers in the survey answered that the current 2015 curriculum's science and elective courses system should be maintained. In the next curriculum, when reconstructing science elective subjects, it is necessary to provide an opportunity to experience the entire contents of each science field through Science I·II system as before, and to ensure student choice in preparation for the credit system. In addition, the opinion that general elective subjects should be organized to include all the contents of science I and II subjects was the highest. Through in-depth interviews, science teachers emphasized that the current science I subject system allows access to the content areas of science as much as possible as the number of subjects is small, and that subjects, such as physics, where the hierarchy of concepts is important, should deal with important content within one subject rather than divided by area. On the other hand, in the current I subject system, there is no subject for liberal arts students to choose from, so teachers suggested that science electives should be organized by subdividing each content area. Based on the research results, the necessity of organizing high school science elective courses in consideration of the purpose of the high school credit system, ways to organize science-convergence elective courses as subjects for all students regardless of career aptitude, ways to organize science-career elective courses, and ways to organize science elective courses in connection with the college admission system were proposed.

• Journal of The Korean Association For Science Education
• /
• v.42 no.3
• /
• pp.311-324
• /
• 2022

This study analyzed the types of scientific emoticons made by science-gifted elementary school students and their perceptions on making scientific emoticons. To do this, 71 students from 4th to 6th graders of two gifted science education center in Seoul were selected. Scientific emoticons made by the students were analyzed according to the number and types. Their perceptions on making scientific emoticons were also analyzed through a questionnaire and group interviews. In the analyses for types of text in the scientific emoticons, 'word type' and 'sentence type' were made more than 'question and answer type'. And the majority of students made more 'pun using pronunciation type' and 'mixed type' than other types. They also made more 'graphic type' and 'animation type' than 'text type' in the images of the scientific emoticons. In the analyses for the information of the scientific emoticons, 'positive emotion type' and 'negative emotion type' of scientific emoticons were made evenly. The students made more 'new creation type' than 'partial correction type' and 'entire reconstruction type'. They also used scientific knowledge that preceded the knowledge of science curriculum in their grade level. The scientific knowledge of chemistry was used more than physics, biology, earth science, and combination field. 'Name utilization type' was more than 'characteristic utilization type' and 'principle utilization type'. Students had various positive perceptions in making scientific emoticons such as 'increase of scientific knowledge', 'increase of various higher-order thinking abilities', 'ease of explanation, use, memory, and understanding of scientific knowledge', 'increase of fun, enjoyment, and interest about science and science learning', and 'increase of opportunity to express emotions'. They were also aware of some limitations related to 'difficulties in the process of making scientific emoticons', 'lack of time', and 'limit that it may end just for fun'. Educational implications of these findings are discussed.

• Korean Journal of Childcare and Education
• /
• v.10 no.6
• /
• pp.223-241
• /
• 2014

The objective of this study was to plan a direction for the connection of the area of inquiry in daily life between infants and young children in Korea based on the analysis of the early learning standards for infants aged 0~2, and young children aged 3~4/5 in 17 different states in America. The problem of the study is as follows: What is the content area of cognitive development, science and mathematics of early learning standards regarding age? The data used in this study was collected from a total of 17 states in America in which 12 states classify infants and young children as aged 0~2 and 3~4/5 respectively and 5 states do not classify the age groups. The results obtained from the analysis of the given issues are as follows. First, in the case of the five states that showed the group aged 0~4/5, the contents related to the area of inquiry in daily life of the early learning standards were included in the mathematics and science and a part of these contents were also included in cognitive developments. In the case of the 12 states that classified the groups aged 0~2 and 3~4/5 respectively, the group aged 0~2 included cognitive developments and the group aged 3~4/5 includes mathematics and science. Second, the contents related to the area of inquiry in daily life of the early learning standards in the five states that showed the single group aged 0~4/5 include the contents in order of scientific idea, biology, physics, and the earth and space. In the 12 states that classify different age groups. Third, in the case of the states that separate age groups, the group aged 0~2 include the contents of number and operation, geometry and space while the group aged 3~4/5 include the contents of number and operations, geometry and space, and measurement. The implications of this study was that it is necessary to take into account the linking between development and characteristics of the subjects.

• Progress in Medical Physics
• /
• v.14 no.1
• /
• pp.34-42
• /
• 2003

In medical imaging, three-dimensional (3D) display using Virtual Reality Modeling Language (VRML) as a portable file format can give intuitive information more efficiently on the World Wide Web (WWW). The web-based 3D visualization of functional images combined with anatomical images has not studied much in systematic ways. The goal of this study was to achieve a simultaneous observation of 3D anatomic and functional models with planar images on the WWW, providing their locational information in 3D space with a measuring implement using VRML. MRI and ictal-interictal SPECT images were obtained from one epileptic patient. Subtraction ictal SPECT co-registered to MRI (SISCOM) was performed to improve identification of a seizure focus. SISCOM image volumes were held by thresholds above one standard deviation (1-SD) and two standard deviations (2-SD). SISCOM foci and boundaries of gray matter, white matter, and cerebrospinal fluid (CSF) in the MRI volume were segmented and rendered to VRML polygonal surfaces by marching cube algorithm. Line profiles of x and y-axis that represent real lengths on an image were acquired and their maximum lengths were the same as 211.67 mm. The real size vs. the rendered VRML surface size was approximately the ratio of 1 to 605.9. A VRML measuring tool was made and merged with previous VRML surfaces. User interface tools were embedded with Java Script routines to display MRI planar images as cross sections of 3D surface models and to set transparencies of 3D surface models. When transparencies of 3D surface models were properly controlled, a fused display of the brain geometry with 3D distributions of focal activated regions provided intuitively spatial correlations among three 3D surface models. The epileptic seizure focus was in the right temporal lobe of the brain. The real position of the seizure focus could be verified by the VRML measuring tool and the anatomy corresponding to the seizure focus could be confirmed by MRI planar images crossing 3D surface models. The VRML application developed in this study may have several advantages. Firstly, 3D fused display and control of anatomic and functional image were achieved on the m. Secondly, the vector analysis of a 3D surface model was defined by the VRML measuring tool based on the real size. Finally, the anatomy corresponding to the seizure focus was intuitively detected by correlations with MRI images. Our web based visualization of 3-D fusion image and its localization will be a help to online research and education in diagnostic radiology, therapeutic radiology, and surgery applications.

• Progress in Medical Physics
• /
• v.24 no.2
• /
• pp.119-126
• /
• 2013

Due to the introduction of CR and DR, it has been neglected the use of the X-ray beam collimator and field size. This study examines nationwide survey of the proper use of collimator and field size by area in a specific field of plain radiography and the current status. Authors emphasized the need for the field size criteria, and propose a standard reference field size in each specific radiologic examination. Total 333 medical institutions (included in Seoul, Gyeonggi-do, Jeolla, Chungcheong, Gangwon-do, Busan area), were investigated in relation to the status of the X-ray beam collimation field size, type specific inspection areas, medical facilities, and image analyses by type to figure out whether they use the adjustment of image field to the specific examination. To assess the awareness and the impact of radiation exposure to the collimation adjustable, 168 radiographers who was working in 10 general hospitals, 10 hospitals, and 10 clinics, were surveyed how they haver adjusted the actual field size. We examine that 61.3% of medical institutions used the "Proper collimation" and only 49.9% of them employed proper one in lumbar spine densely crowded by major organs. 69% among general hospitals, and 65% among hospitals using DR system were using proper collimation. Radiographers recognized that proper adjustment of collimation could reduce the harmful radiation dose on patients. In the survey, 97.6% of respondents were aware of this fact, but only 83.3% of respondents did the adjustment of the size of the collimation field. The using of proper collimation field was low in the nationwide survey, so the effort to reduce the radiation dose on the patients is urgently needed. A unified standard for the field accompanied by thorough education should be needed.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.15 no.6
• /
• pp.252-259
• /
• 2005

Single crystal $CuGaSe_2$ layers were grown on thoroughly etched semi-insulating CaAs(100) substrate at $450^{\circ}C$ with hot wall epitaxy (HWE) system by evaporating $CuGaSe_2$ source at $610^{\circ}C$. The crystalline structure of the single crystal thin films was investigated by the photoluminescence (PL) and double crystal X-ray diffraction (DCXD). The carrier density and mobility of single crystal $CuGaSe_2$ thin films measured with Hall effect by Van der Pauw method are $4.87{\times}10^{17}cm^{-3}$ and $129cm^2/V{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $CuGaSe_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=1.7998eV-(8.7489{\times}10^{-4}eV/K)T^2/(T+335K)$. The voltage, current density of maxiumun power, fill factor, and conversion, efficiency of $n-CdS/p-CuGaSe_2$, heterojunction solar cells under $80mW/cm^2$ illumination were found to be 0.41 V, $21.8mA/cm^2$, 0.75 and 11.17%, respectively.

• Journal of Radiation Protection and Research
• /
• v.35 no.2
• /
• pp.85-90
• /
• 2010

In the present work, peak relative efficiency for the energy was obtained and response function was worked out. This study was carried out using the high resolution high efficiency HPGe detector(diameter 78.7 mm, length 86.5 mm) and NaI(Tl) detector for anti-compton. The anti-coincidence of the signals from the two detectors could be used to lessen the Compton effect signal; thus, the $\gamma$-ray energy resolution could be improved. The $\gamma$-ray spectrum was measured at $55^{\circ}$ to the direction of the incident proton beam. Reaction spectrum was obtained from the $^{23}Na$(p, $\gamma$)$^{24}Mg$ reaction at $E_p$ = 1424 keV and $^{27}Al$(p, $\gamma$)$^{28}Si$ reaction at $E_p$ = 992 keV. To accelerate the incident proton which creates the (p, $\gamma$) capture reaction, the 3 MeV Pelletron accelerator at the Tokyo Institute of Technology was used. Response function was worked out by a noble technique. We worked out a response function from 1.2 to 9.4 MeV at intervals of 0.75 MeV.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.4
• /
• pp.2476-2483
• /
• 2014

This study aims to review the characteristics of specialized classrooms for governmental secondary schools in the Japanese Colonial Era by analyzing architectural drawings collected by National Archives of Korea. The results of this study are summarized as follows 1) Under the influence of Japanese science promotion of that time, specialized classrooms for science were considered as one of essential facilities. Typically exclusive specialized classrooms were assigned to two major science subjects : physics-chemistry and biology. 2) To science specialized classrooms, ancillary rooms for preparation, experiment equipment and specimen were attached and science lecture room with stepped floor was planned additionally only for the lecture on theories and the demonstration of experiment. 3) Specialized classrooms for science were zoned independently of other facilities because of the special equipments and safety. 4) Art rooms were common to both boys' and girls' schools but concerning music rooms, girls' schools had special concerns, whereas boys' schools did not. 5) Specialized classrooms for homemaking subject of girls' school were as much important as those for science subjects of boys' school. 6) Some early-established Korean boys' schools had handicraft rooms which were the symbol of vocational education-oriented, unequal policy on Koreans. Though not general cases, specialized classrooms for geography-history were planned for Japanese boys' school. Restricted to governmental secondary schools but considering the uncommon state of specialized classrooms of that time, these characteristics show conditions of early time when special classrooms were introduced into Korea.