• Journal of The Korean Association For Science Education
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• v.19 no.1
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• pp.91-99
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• 1999

The researches related to students' preconceptions and conceptual change model have been reported that students' learning motivation is one of the key variable for the conceptual change. The effects of students learning motivations on conceptual changes were evaluated. Subjects of this study were 8th grade students. and they were divided into 2 groups. One group was taught by traditional teaching method, and the other group by concept change teaching model. After the intervention, learning motivations of the students were testified. The students of high motivation who were taught by concept change teaching model showed higher scores in the concept of chemical change than the students by traditional teaching method. But there was no difference in both groups of students who have low learning motivations. The learning motivations before the intervention. the motivations stimulated by classes. and the degree of concept understanding showed high correlation. The motivations stimulated by classes explain 23.3 % of the degree of concept understanding. The results seems to mean that students learning motivations contribute to the understanding of concepts. Especially confidence of learning as a subcategory of the learning motivation contributes significantly to the understanding of new concepts. In contrast, the traditional teaching methods and the teaching methods of concept change learning theory were not effective for the stimulation of students learning motivations.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.7 s.196
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• pp.75-82
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• 2007

This paper represents a study on the development of the conceptual design for the bicycle transmission by TRIZ. At first the problem of the transmission of commercial bicycles was analyzed. The problem was defined as "the variable sprocket pitch diameter with respect to the tension change of chain". The conceptual solutions were derived by Su-Field Model Analysis, IFR(Ideal Final Result), SLP(Smart Little People), and Contradiction Matrix. The here developed sprocket prototype shows the automatic change of sprocket pitch diameter with the tension change of chain.

• Journal of The Korean Association For Science Education
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• v.18 no.3
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• pp.347-355
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• 1998

This paper reports on a way of using cognitive conflict in order to bring about conceptual changes. Cognitive conflict occurs when there is a discrepancy in students mind between everyday events and the scientific concepts which are used to explain these events. In order to overcome this conflict auxiliary scientific hypotheses can be introduced, which makes the resolution easier. In this paper, we suggest a new model of conceptual change and a model of instruction named 'structured contrastive activity' which consists of three stages: contrastive discussion by introducing the auxiliary hypotheses for clarifying the cognitive conflicts of students, observing the phenomena in idealised contexts in order to increase the status of the scientific concepts, laboratory experiments which bridge the two contexts.

• Journal of The Korean Association For Science Education
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• v.36 no.1
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• pp.125-134
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• 2016

The purpose of this study is to explore the relationship between motivational belief about learning science, self-directed learning ability and conceptual understanding of matter change with a quantitative method, assuming that motivational belief and self-directed learning ability might affect conceptual understanding. To do this, the authors investigated middle school students' motivational belief about learning science, self-directed learning ability, and conceptual understanding of matter change using measurement tools based on previous studies, and then analysed the casual relationship between three variables using PLS structural equation model. As a result, three latent variables in this study could be evaluated as appropriated in reliability and validity. And also, self-directed learning ability could affect both the motivational belief and conceptual understanding, while motivational belief could affect only self-directed learning ability but not conceptual understanding. Through this study the authors confirmed that in the context of science learning self-directed learning ability can directly affect conceptual understanding but motivational belief can affect indirectly. This study is significant in that the causal relationship between different variables in science learning could be confirmed in a quantitate manner, and also in that it can suggest PLS structural equation method as a new research methodology in science education research area.

• Journal of the Korean Society of Systems Engineering
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• v.20 no.spc1
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• pp.97-107
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• 2024

Efforts to respond to climate change are being made in various ways around the world, and in the energy field, continuous research and pilot projects are underway through new and renewable energy, efficient power grid management, and power grid services. Systems are in place to realize these efforts, and the systems created allow for better effectiveness. When implementing a system, systems engineering methodology helps design a more systematic system and can provide verification accuracy and uniformity through intuitive connectivity. In this paper, the original requirements of the power grid stabilization system and the architecture of the system's essential constraints are constructed as a conceptual model and the boundaries and flows between components are defined. By utilizing distributed resources such as EV(Electric Vehicle) and ESS(Energy Storage System) in the power service platform system, we plan to design and build a next-generation power service system that can participate in the power stabilization market and implement a system necessary to respond to climate change in the future.

• Journal of The Korean Association For Science Education
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• v.23 no.4
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• pp.360-374
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• 2003

The idea that students must experience cognitive conflict before conceptual change can occur is not new. In light of this idea, many teaching strategies have been applied in educational practices. However, there is not much literature about how students are experiencing cognitive conflict, how this experience affects students learning processes, and how we use that knowledge to improve our science instruction. This study aimed to propose possible answers about these questions. In this paper, we conducted the first question as a first part of our research. To do this, we reviewed related literature and analyzed protocols that were produced in previous studies. As a result, a model of cognitive conflict was developed. This study's findings may lead to further understanding and use of students' cognitive conflict, which has a complex role in science instruction.

• Journal of the Korean earth science society
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• v.27 no.1
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• pp.6-14
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• 2006

The study investigates mental models of scientifically gifted, middle school students when it comes to tides. This was done by analyzing facet of conceptual types for two contexts. We carried out two performance tasks of tide with different context. A large number of students showed different conceptual types by context. As a result of analyzing facet of conceptual types by context, there was a slight difference in content-specific facet, but a remarkable one in strategic facet. We classified four mental models about tide by configuring facets of conceptual types: (1) Tide model (2) Force model (3) Phase model (4) Hybrid model. The Tide model is scientifically accepted model, but Force model and Phase model are incorrect models, and Hybrid model is mixed model. In cases of Force model and Phase model, conceptual types concur with each other, but these types of students comprehend tides as a result of joined forces of Moon & Sun and phase change of Moon, respectively. Arranging low mental models in proportional order, Tide model (45.0%), Hybrid model (30.0%), Force model (12.5%), and Phase model (7.5%).

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.611-620
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• 2010

The purpose of this study was to explore the structure and content of chemistry teacher's explanations from the perspective of 'persuasion'. Especially, this study was to explore how the argument structure and the conceptual change constructs in chemistry teachers' explanations were established and interacted. Data were collected from chemistryI classes considering the gas unit which includes kinetic theory of gas, Graham's law, Boyle's law, and Charles' law. The classes were vediotaped and transcribed. The transcriptions were analyzed with Toulmin's argument frame and the two constructs of conceptual change model; the conceptual ecology and the status of a conception to interpret the persuasive structure and content of the teacher's explanations. As the results of this study, four explanatory discourses which show various persuasive explanations in chemistry classes. Based on this results, discussion and implications for effective teachers' explanations in chemistry classes were presented.

• Korean Journal of Construction Engineering and Management
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• v.10 no.5
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• pp.104-112
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• 2009

After the middle of 90's, the eco rivers maintenance enterprise was propelled about city rivers. The environmental function is more emphasized because of revising the rivers law enforced at 2008.4. Also, the field of application is being magnified. It is difficult to apply that the conceptual public work expense estimating model of the rivers which adjusts a focus at open channel rivers excepts the small-scale rivers maintenance public work. The research presents a eco rivers public work conceptual public work expense estimating model frame work. It suits the change of the rivers environmental renewal construction paradigm. It develops the conceptual public work expense estimating plan of the rivers at the planning phase using the collection and analysis of the data. As a result, riffle, spur dyke, stepping stones, fish way and etc are added. Consequently, it brings the hydrophilic function is considered seriously conceptual public work expense estimating model of the eco rivers.

• Spatial Information Research
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• v.10 no.4
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• pp.515-532
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• 2002

Planning Support System (PSS), an alternative framework of computer-aided planning system combining geographic information system (GIS), urban models, and visualization tools, has been actively researched and applied in many developed countries. This paper introduces a PSS-based land use change model, What if\ulcorner PSS, by applying it to Chongju City, Korea. This model application study used the spatial database, Restricted Development Zone (RDZ), and other hypothetical land supply- and demand-related policies of Chongju City. The collaborative PSS model supported land use planning process by helping users to speedily and easily create and test policy-oriented scenarios. The study found that the fully operational PSS model was readily applicable and useful to Korean local land use planning. The paper discusses the conceptual model framework, data requirement, application process, model output, and practical usage. This study would be considered as a prototypical approach of PSS-based land use plan making for Korean cities.