• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.578-579
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• 2006

• The Journal of the Korea Contents Association
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• v.10 no.5
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• pp.427-435
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• 2010

We extracted core terms by constructing scientific item networks from textbooks, analyzing their structures, and investigating the connected information and their relationships. For this research, we chose three high-school textbooks from different publishers for each three subjects, i.e, Science, Biology I and Biology II, to construct networks by linking scientific items in each sentence, where used items were regarded as nodes. Scientific item networks from all textbooks showed scare-free character. When core networks were established by applying k-core algorithm which is one of generally used methods for removing lesser weighted nodes and links from complex network, they showed the modular structure. Science textbooks formed four main modules of physics, chemistry, biology and earth science, while Biology I and Biology II textbooks revealed core networks composed of more detailed specific items in each field. These findings demonstrate the structural characteristics of networks in textbooks, and suggest core scientific items helpful for students' understanding of concept in Science and Biology.

• Journal of the Korean Society of Earth Science Education
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• v.17 no.1
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• pp.49-59
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• 2024

In this study, we investigated the philosophical background and progress of the 2022 revised curriculum development in the high school earth science field. Research that was not covered in the research report includes the relevance of the transformative competency of OECD Education 2030, and that core ideas and achievement standards are organized around knowledge understanding, process functions, and value attitudes that constitute the learning compass needle. In addition, the composition of core ideas and Earth science electives in light of the understanding-centered curriculum, and IB type inquiry-based teaching and learning. Main research results include that the 2022 revised Earth science curriculum emphasized the student agency to foster the transformative competency and scientific literacy, and the curriculum document system in the field of earth science uses a learning compass needle. In addition, based on the understanding-centered curriculum, core ideas of Earth science were derived, and elective courses were organized to help students reach these core ideas. Also, IB-type inquiry-based teaching and learning was emphasized to foster student agency with knowledge construction competency. Based on the research results, slimming of the national and general level curriculum, the need to develop process-centered assessment methods for value and attitudes, the need for curriculum backward design, and ways to develop student agency through inquiry-based teaching and learning were suggested.

• Journal of Korean Academy of Nursing
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• v.39 no.6
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• pp.851-859
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• 2009

Purpose: The purpose of this study was to evaluate the effects of a core competency support program on depression and suicidal ideation in adolescents. Methods: A quasi-experimental design was employed in this study. Participants for the study were high school students, 27 in the experimental group and 29 in the control group. Data were analyzed using the SPSS/WIN. 14.0 program with $\chi^2$ test, t-test, and ANCOVA. Results: Participants in the core competency support program reported decreased depression scores significantly different from those in the control group. Participants in the core competency support program reported decreased suicidal ideation scores, also significantly different from those in the control group. Conclusion: The core competency support program was effective in decreasing depression and suicidal ideation for adolescents. Therefore, this approach is recommended as a suicide prevention strategy for adolescents.

• Journal of Power Electronics
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• v.19 no.6
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• pp.1467-1476
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• 2019

Grid unbalanced faults can cause core saturation of power transformer and produce lower-order harmonics. These issues increase the electrical stress of power electronic devices and can cause a tripping of an entire HVDC system. In this paper, based on the positive-sequence and negative-sequence impedance model of a VSC-HVDC system as seen from the point of common connection (PCC), the resonance problem is analyzed and the factors determining the resonant frequency are obtained. Furthermore, to suppress over-voltage and over-current during resonance, a novel method using a virtual harmonic resistor is proposed. The virtual harmonic resistor emulates the role of a resistor connected in series with the commutating inductor without influencing the active and reactive power control. Simulation results in PSCAD/EMTDC show that the proposed control strategy can suppress resonant over-voltage and over-current. In addition, it can be seen that the proposed strategy improves the safety of the VSC-HVDC system under unbalanced faults.

• Journal of Sensor Science and Technology
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• v.18 no.5
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• pp.393-401
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• 2009

This paper describes development of a new displacement sensor for intelligent suspension system in which the damping force has been controlled by MR fluid. Most of the current vehicle height sensors have been installed at external place of the damper and connected to that by mechanical linkages so far. The developed sensor has a new mechanism which detects movement of the sensor rod same as connecting rod in the suspension damper by using a GMR Sensor and converts it to the relative displacement from an initial position.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.3
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• pp.932-940
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• 2017

This study investigated the perception of pre - service teachers in order to find out how paper textbooks are used in high school classes and what improvement is needed. Firstly, the results of analyzing the perception about the utilization of textbooks are as follows. First, in the case of Korean language, social studies, mathematics, science, and English, textbooks were used most frequently, and most of the respondents did not use textbooks for arts and physical education subjects. Secondly, Korean language, social studies, mathematics, science, and English textbooks are most frequently used as teaching materials. Third, in the case of Korean, social, mathematics, science, and English subjects, in addition to textbooks, problem collections were used most frequently and arts and physical education subjects showed the most use of prints. Next, the results of analyzing the perception of the improvement method of the textbooks are as follows. First, in the high school class, the response rate was high in that Korean, social, mathematics, science, and English classes needed a textbook. Most of the respondents answered that they were not necessary for the textbooks of arts and physical education subjects. Second, in order to improve the textbooks, the most demanding textbooks focused on the core basic contents, followed by self - directed learning activities, competency centered contents selection, cooperative learning activities, and teacher self - development. The demand for digital textbooks was low.

• Parasites, Hosts and Diseases
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• v.61 no.4
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• pp.418-427
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• 2023

Toxoplasma gondii infections are primarily diagnosed by serological assays, whereas molecular and fluorescence-based techniques are garnering attention for their high sensitivity in detecting these infections. Nevertheless, each detection method has its limitations. The toxoplasmosis detection capabilities of most of the currently available methods have not been evaluated under identical experimental conditions. This study aimed to assess the diagnostic potential of enzyme-linked immunosorbent assay (ELISA), real-time polymerase chain reaction (RT-PCR), immunohistochemistry (IHC), and immunofluorescence (IF) in BALB/c mice experimentally infected with various doses of T. gondii ME49. The detection of toxoplasmosis from sera and brain tissues was markedly enhanced in mice subjected to high infection doses (200 and 300 cysts) compared to those subjected to lower doses (10 and 50 cysts) for all the detection methods. Additionally, increased B1 gene expression levels and cyst sizes were observed in the brain tissues of the mice. Importantly, IHC, IF, and ELISA, but not RT-PCR, successfully detected T. gondii infections at the lowest infection dose (10 cysts) in the brain. These findings may prove beneficial while designing experimental methodologies for detecting T. gondii infections in mice.

• Journal of the Korean Society of Earth Science Education
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• v.7 no.2
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• pp.169-179
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• 2014

The purpose of this study is to research about the effects on improvement academic achievement of students based on the core learning standards of science. The researcher selected experimenter and started this study as a graduate student who is majoring in science education, experimenter chose to study 48 Sixth graders in elementary schools in B city for research group(24 students), Comparison group(24 students). The study was conducted from March to the end of July 2014. The teacher who is doing activity of professor in research group and the comparison group is science education specialist. Researcher and experimenter frequently exchange their opinions for control variables of teacher. The results are as follows. First, based on unit time strategies based on core achievement standards classes are effective in improving students' academic achievement. Elementary school teacher has difficulty in teaching for all subjects based on unit time strategies. Second, based on unit time strategies based on core achievement standards classes showed high level of satisfaction in perception of students. Thus it can be seen that teaching strategies of unit time based on the core achievement standards is effective to academic achievement improvement. The proposal for further study based on the results is as follows. First, research is needed to study the teaching methods that have practical and theoretical study time and lesson application opportunity for teaching strategies of curriculum unit time. Second, experimental studies that using strategies of unit time based on the core achievement standards are needed about learning method that can be applied in a variety of subjects.

• Journal of The Korean Association For Science Education
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• v.39 no.4
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• pp.525-534
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• 2019

The purpose of this study is to investigate the influences of Science Core schools on students' positive experiences about science (PES) through in-depth interviews with teachers in charge of science core schools. In-depth interviews with teachers were conducted to explore the factors that led to the effectiveness of science core schools in improving the student's PES in light of operational characteristics of science core schools as leading schools, characteristic factors of science core schools on students PES, and improvement plans and requirements of science core schools as leading schools, as well as implications for general high schools. In the case of science core schools, the teacher's enthusiasm for science teaching encouraged students' participation in science classes, promoted students' interest in science other than science-core classes, improved students' inquiry and research skills, increased students' competencies such as communications and collaboration by improving science instructions, and affected career search and exploration based on interests in science experiences. Based on the results, ways to spread the characteristics of science core schools to general schools' curriculum implementation are suggested including providing opportunities to experience the value of science study, to experience science and engineering careers through senior students, to participate in team projects and self-regulated science inquires, and so on.