• Journal of the Korean Society of Industry Convergence
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• v.10 no.1
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• pp.5-14
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• 2007

It is necessary for development of drawing product with press to have suitable material selection & all process design and the problem during press process has been cleared from judgement of experience & trial and error. Recently we can estimate press process result from computer aided design & FEM. But we can get more reliable result when we can put more precise process variants during FEM. In case of using a drawbead that is used for the material inflow, it is considered for us to put material property, other analysis condition & friction figure when material is passing through the drawbead for better FEM. From our study, we have drawn an analogy bead connection depth, friction figure & drawing and restraining load according to kinds of lubrication from experiment & FEM for the drawbead. We applied above result to the drawing experiment & FEM and confirmed the validity. We could notice the relation between friction figure & drawing load and the friction figure variation according to kinds of lubrication. It is expected to draw more precise analogy that can be used for real process due to more precise process variants application to FEM.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.759-764
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• 2000

The accurate prediction of aeroacoustic analysis is necessary for designers to control and reduce airflow-induced sound pressure levels in high speed rotating DVD drives. This paper focuses on the numerical prediction of airflow-induced sound in DVD drives. Computational fluid dynamics(CFD) is first conducted to evaluate flow field characteristics due to the high-speed disk rotation, and to support the acoustic analysis. The acoustic analogy based on Ffowcs Williams-Hawkings(FW-H) equation is adopted to predict aeroacoustic noise patterns. The integral solution for quadrupole volume source is included to identify the turbulence noise generated inside the DVD tray. The strength of sound pressure level with respect to rotating speed is discussed to meet upfront demand on the high fidelity product development. The present study also focuses on the noise directivity and examines how much the sound noise is sensitive to change in rotating speed. Near-field noise is strongly affected by the flow field characteristic, which is caused by the complex shape of the tray. For a mid-field, the quadrupole noise play as a counterpart of thickness noise or loading noise, so it generates different sound noise patterns compared with those in the near field.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.753-754
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• 2008

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.1
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• pp.1-9
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• 2013

In this paper, numerical simulations are performed on the lock-in phenomena of vortex induced vibration(VIV) of a two dimensional cylinder. A deforming grid as well as a rigidly moving grid are used to simulate the movement of the cylinder. The grid deformation is accomplished by the linear spring analogy. Converged solutions, which are obtained by controling the grid size and the non-dimensional time step, are used for comparison and validation of the analysis results. Moreover, the efficiency and the accuracy of the coupling methods for fluid-structure interaction are examined.

• Journal of the Korean Society of Costume
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• v.64 no.2
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• pp.113-125
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• 2014

Creative thinking requires an ability to draw ideas on the given topic in a given time period with concentration. For this, the development process of design concept on the topic was collected through experiments and interviews targeting 10 fashion education experts and 10 clothing majors. After the analysis, the results are as follows: First of all, divergent thinking was done to find as many ideas and possibilities as possible at the step of expanding the topic by analogy. This showed characteristics of spreading thoughts through the spread of lexicon to professional field knowledge of learned, individual's cultural background, other art fields. Second, abstracted and designed words that are expanded and listed by the topic analogy were specified the topic gradually through the free combination method between lexicons. The sentences made by the combination of lexicons were interpreted through the serial listing method, in which the connection between sentences had the meaning of orderly cause and effect form, and the parallel listing method that treated information at once. Third, the few characteristics of the procedure that visualizing into the specific design are as follows. Firstly, the method to transform image that lexicon has into the one appropriate to the topic, the case that reflects external characteristics of selected designed word, and the case which reflects as the extrinsic expression of personal immanent and tactic desires. This study has its means to propose methods and directions to help create more creative and systematic ideas by analyzing the characteristics that appeared during the process of thinking language-oriented design.

• Journal of the Korean Chemical Society
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• v.57 no.3
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• pp.398-404
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• 2013

In this study, the analogies in the chemistry domain of middle school science textbooks developed under the 2007 revised National Curriculum were analyzed. A total of 235 analogies were found in 27 middle school science textbooks analysed, which means that one analogy per 10 pages was used on average. The number of analogies found in each textbook considerably varied depending on both publishing company and chemistry domain. Functional analogies, verbal and pictorial analogies, analogies with abstract target and concrete analog, enriched analogies, everyday contexts analogies, student-centered analogies, and analogies with low systematicity were frequently used. On presenting the analogies in the textbooks, the term analogy and description about the limitations of the analogies were rarely mentioned. In comparison with the analogies in the science textbooks developed under the 7th National Curriculum, the frequency of analogies per page was increased. There were positive changes in the aspects of representation, extent of mapping and artificiality. No differences, however, were found in the patterns of the other aspects.

• Proceedings of the KSR Conference
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• 2000.05a
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• pp.529-536
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• 2000

This paper describes the analysis of aerodynamics and the prediction of airflow induced noise around simplified pantograph. First, computational fluid dynamics (CFD) is conducted far several model to evaluate linear/nonlinear flow field characteristics due to high speed flow and the CFD results support the computational aeroacoustics. The accurate prediction of the aeroacoustic analysis is necessary for designers to control and reduce the airflow induced noise. We adopt the acoustic analogy based on Ffowcs Williams- Hawkings (FW-H) equation and predict aeroacoustic noise.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.150-157
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• 2010

In this study, we investigated the differences of mapping understanding and the types of mapping errors by the levels of students' cognitive/affective variables and the relationships between mapping understanding and these variables in learning 'concentration and reaction rate' with analogy. After administering the tests regarding logical thinking ability, visual imagery ability, analogical reasoning ability, self efficacy, and need for cognition as pretests, students learned with analogy. Then, students' familiarity and mapping understanding were examined. Analyses of the results revealed that the scores of the mapping understanding for the students with higher levels of all cognitive/affective variables except visual imagery ability and familiarity were significantly higher than those for the students with lower levels. The differences in the types of the mapping errors such as overmapping, failure to map, impossible mapping, artificial mapping, mismapping, rash mapping, and retention of a base feature were also found by the levels of students' cognitive and affective variables. The scores of students' mapping understanding were positively correlated with those of all cognitive and affective variables. The results of multiple regression analysis indicated that students' science achievement, logical thinking ability, and familiarity were significant predictors of mapping understanding. Educational implications of these findings are discussed.

• Journal of Korean Society for Quality Management
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• v.46 no.4
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• pp.821-842
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• 2018

Purpose: To derive key requirements and key technologies for weapon system acquisition business by using Qualify Function Deployment (QFD), and to reduce business cost by setting the target performance and key expense of weapon system. Methods: We propose a QFD methodology that can induce rational decision-making by translating analyst's subjective opinions into quantitative values when analyzing requirements at the initial stage of weapon system development project. Based on QFD methodology, QFD application model combining house of quality, value engineering, and analogy cost estimating technique is presented. Results: It was possible to analyze the specific requirements necessary for the development of the weapon system, to solve the communication problem of the participants, to set clear development direction and target. Conclusion: By applying the QFD application model at the early stage of the weapon system acquisition project, it is possible to reduce the business cost by establishing clear development direction and goal through the procedural analysis process.

• Journal of The Korean Association For Science Education
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• v.27 no.7
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• pp.631-638
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• 2007

This study investigated the influences of a student-centered analogical instruction using physical analogies upon students' conception and application, retention of conception and application, perceptions of science classroom environment, and perceptions of analogical instruction. Six classes of seventh graders (N=208) at a middle school in Seoul were assigned to the control, the teacher-centered analogy (TCA), and the student-centered analogy (SCA) groups. They were taught about 'three states of matter' and 'motion of molecules' for 8 class hours. Analysis of the results revealed that the scores of the SCA group were significantly higher than those of the other groups in the conception test, retention test of conception and application, and perception test of science classroom environment. The scores of the SCA group in the application test were also higher than those of the other groups, but there was a significant difference only between the control and the SCA groups. The TCA group performed significantly better than the control group only in the test of the retention of application. In addition, the students in the SCA group exhibited more positive perceptions of the analogical instruction than those in the TCA group. Educational implications are discussed.