• Journal of The Korean Association For Science Education
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• v.31 no.3
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• pp.440-454
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• 2011

This study proposes a new instructional strategy and corresponding materials designed from various alternative frameworks to help students understand evolution as a biologically acceptable theory. Biology teachers have normally taught the evolutionary mechanism by means of comparing Lamarckism with natural selection. In this study, a new instructional strategy in which the Lamarckian explanation is first excluded because Lamarckism is known to be subsumed in a learner's cognitive structure as a strong preconception of evolution is suggested for teaching evolution. After mutation theory is introduced, Darwinism including natural selection is explained separately during the next class hour. Corresponding instructional materials that aid student understanding of the evolutionary mechanism were developed using recently published articles on human genetic traits as scientific evolutionary evidence instead of the traditional evolutionary subject matter, giraffe neck. Evolutionary evidence from human genetic traits allows students to exclude anthropocentric thoughts effectively and raise concern for the phenomenon of evolution positively. The administered instructional strategy and materials in this research improved student conception, concern, and belief of evolution and it is believed that they helped students understand the evolutionary mechanism effectively.

• Journal of The Korean Association For Science Education
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• v.35 no.1
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• pp.15-25
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• 2015

This study examined pre-service secondary physics teachers' epistemological beliefs about scientific knowledge, science learning, and science teaching in two different science content topics, Lamarckism and the impetus theory. Two sets of open-ended questionnaires, for each of the topics respectively, were developed in the same format. The pre-service teachers completed the questionnaires at one month intervals. The beliefs were analyzed in two dimensions, knowledge justification and knowledge change for each belief area. The findings show that the majority of pre-service teachers held sophisticated epistemological beliefs about scientific knowledge regardless of content topics. On the other hand, more pre-service teachers exhibited sophisticated beliefs about science learning in the context impetus theory than Lamarckism. In the area of science teaching, the majority of pre-service teachers demonstrated a sophisticated view in knowledge justification but a naive view in knowledge change. When consistency across science topics and belief areas were examined, few pre-service teachers held consistent epistemological beliefs across all topics and areas. The difference in the levels of sophistication in belief areas showed that the pre-service teachers did not connect their epistemological beliefs about science knowledge to their ideas about science teaching and learning. This disconnection seems to make the consistency across topics and areas complicated. The difference in epistemological beliefs about science learning and teaching between two science topics need further inquiry. Implications for teacher education are offered.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.2
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• pp.299-304
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• 2018

An improved genetic algorithm was proposed for pattern synthesis of an adaptive beam forming system using phased array antennas. The proposed genetic algorithm is an algorithm that adds acquired characteristics procedure to solve local optimization using the diversity. The performance of the proposed genetic algorithm is verified through the problem of finding a suitable chromosome for a picture composed of binary. And it is confirmed that it is suitable for the adaptive beam forming system based on the performance problem of combining main beam and two pattern nulls.