• Journal of The Korean Association For Science Education
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• v.24 no.3
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• pp.583-595
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• 2004

The purpose of this study was to identify whether the elementary school students force conceptions may influence on designing tools experiments. Four questions with multiple choices and reasons for those choices were asked to identify scientific/alternative force conception. Also four tasks for tools experiments matched to each force conceptions were developed into open questions in hypothesizing. controlling variables and methods of experiments. Forty elementary students were selected from 4 classes in sixth grade of a school in Daegu city. The major findings of this study were that the types of force conceptions can be classified into scientific and alternative conceptions. The patterns of designing experiments could be identified with types of hypothesis, controlling variables and methods of experiments in each four tools experiments. But students those who had scientific force conception did not better in hypothesis, methods of controlling variables and results for simple experiment than those who had alternative force conceptions. These results imply that students' force conception did not influence on designing tools experiments. The assumption that scientific conception could improve designing experiments was not guaranteed by this results.

• Journal of The Korean Association For Science Education
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• v.17 no.4
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• pp.383-393
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• 1997

In order to study the effect of student's conceptions about force and motion into the graph construction in kinematics in college physics course, the tasks of constructing the qualitative graph in the similar problem context used in force conception was asked to the first 74 and third 97 student teacher in teachers' university. The frequencies analysis showed that student teachers had the naive conceptions that the throwing force was still acted to a upwarding ball. They also had the popular Aristotelian views about motion. These naive conceptions coexisted with the scientific conception about gravitational force. In a simple pendulum problem no one had the correct acceleration concepts which varies the direction in swing. This result suggest that student teacher had more difficulties in a acceleration problem than in a velocity problem In v-t and a-t graph construction tasks, the number of categories of a-t graphs were more than that of v-t graphs. There were many graph errors in a sign of velocity and acceleration. The acceleration conceptions without the relations of changes in velocity made the kinematics graphs more various shapes. The force and motion conceptions influenced the ability to construct the kinematics graphs.

• Journal of The Korean Association For Science Education
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• v.26 no.7
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• pp.805-812
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• 2006

In this study the description patterns of chemistry textbooks on the boiling point elevation phenomenon and the understanding patterns of high school students, pre-service teachers and chemistry teachers were investigated. High school chemistry II textbooks developed in the 6th and 7th national curricula were analyzed and the conception patterns of subjects on this phenomenon were categorized using a questionnaire developed for this study. The description patterns of science textbooks were classified into three: 'decreasing of surface solvent molecules', 'attraction force between solvent and solute molecules' and 'decreasing of surface solvent molecules and attraction force between solvent and solute molecules'. In the result of the conception analysis, the ratio of 'attraction force between solvent and solute molecules' was high among students, pre-service teachers, and chemistry teachers. There was a propensity that they would like to explain the boiling point elevation in terms of enthalpy rather than entropy, and in order to analyze this propensity, follow-up interviews were carried out.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.447-454
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• 1998

The main object of the study is that axial force-moment relationships for high strength concrete structures using reliability theory(Linear statstical method, Monte Carlo Simulation) including probability conception. And mean stress factors and centroid factors proposed to high strength concrete structures using reliability theory(Linear statstical method, Monte Carlo Simulation). Finally, The established experimental data for axial force-moment relationships are compared to the analytical data(data for Linear statstical method and Monte Carlo Simulation) for axial force-moment relationships in this analytical method.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.500-506
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• 1997

The main object of the study is that axial force-moment relationships for high strength concrete structures using reliability theory probability conception. And mean stress factors and centroid factors proposed to high strength concrete structures using reliability theory. Finally, the established experimental data for axial force-moment relationships are compared to the analytical data for the axial force-moment relationships in this analytical method.

• Journal of The Korean Association For Science Education
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• v.7 no.2
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• pp.61-70
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• 1987

This paper was made for the purpose of examining middle school student's conception about force and motion. Using questionaire method. this research was executed to 180 students at a middle school in Seoul. Questions were as following; 3 questions about relation of the direction of force and that of motion in case of throwing a ball up, 2 questions about parabolic motion. 1 question about inertia. and 1 question about action and reaction. The way of answering was both selecting and explaining the students' thought about questions. Network analysis was used for analyzing students' various responses. Through the analysis. some types of students' thought were revealed. As a result the representation of their response was motion implies force which had been discovered by earlier researchers. Even though students had learned about force and motion in the classroom. their ideas were unchanged or even reinforced wrongly in some case.

• International Journal of Aeronautical and Space Sciences
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• v.7 no.1
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• pp.27-42
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• 2006

A method to design the contour and conception of a plug nozzle of arbitrary shape, but specified exit flow conditions is presented. Severals shapes can be obtained for exit Mach number by changing the specific heats ratio. The characteristics of the nozzle in terms of length, weight and pressure force exerted on the wall are compared to the Minimum Length Nozzle and found to be better. Our field of study is limited to the supersonic mode to not to have the dissociation of the molecules. The design method is based on the use of the Prandtl Meyer function of a perfect gas. The flow is not axial at the throat, which may be advantageous for many propulsion applications. The performance benefits of the plug nozzle compared to the Minimum Length Nozzle are also presented.

• Journal of English Language & Literature
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• v.57 no.6
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• pp.939-958
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• 2011

Ezra Pound has an idea of poetry as a field of energy in which words interact with each other with kinetic energy. The energy field which Pound creates in his poem is analogous to the theory of electromagnetism developed by Michael Faraday and James Maxwell, who look upon the space around magnets, electric charges and currents not as empty but as filled with energy and activity. Pound argues that "words are charged with force like electricity," demonstrating that words charged with their own images or energies of positive or negative valence interact one another. This idea is similar to Faraday's concept of "line of force" which he used to represent the disposition of electric and magnetic forces in space. Pound's concept of "image" as an "intellectual and emotional complex in an instant" is remarkably consonant with the confluence of electric and magnetic fields that are coupled to each other as they travel through space in the form of electromagnetic waves. The instant profusion of conception and perception, much like that of electric and magnetic fields, enables Pound to move beyond the sequential and linear hierarchy in time and space. Particularly, Maxwell's stunning discovery that the electromagnetic waves propagate in space at 'the speed of light' has allowed Pound a relativistic sense of escape from the limitations of Newtonian absolute time and space. Pound's poetry transcends any geographical space and sequential time by rendering and juxtaposing images simultaneously. Pound was fully aware of light and electricity fundamental to what he called his world "the electric world." Pound's experiments in Imagism and Vorticism can be considered an attempt to rediscover a place for poetry in the modern world of science and technology. Almost all the appliances that we think of today as modern were laid down in the closing decades of the 19th century and the first decades of the 20th century, in response to the availability of electromagnetic energy. This paper explores how Pound responded to the age of modern technology and science, examining his conception of "image" through his many analogies and similes drawn from electromagnetism. Pound's imagist poetics and poetry come to embody, not only the characteristics of the electric age in the early twentieth century, but the principles of electromagnetism the electric age is based upon.

• Journal of The Korean Association For Science Education
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• v.26 no.5
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• pp.611-619
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• 2006

The aims of this study are to investigate science high school students' understanding of velocity and acceleration of a simple pendulum bob, and to investigate their understanding of inertia and gravitational force in the motion of a pendulum bob when the tension is removed. For the study, 46 students that had already studied the physical, concepts in simple pendulum were sampled from a science high school in a large city in Korea. For a comparison with general high school students' conceptions, 49 students were sampled from a general high school in the same city. The test tool for the investigation consisted of four drawing and simple-answering type questions developed by the authors. The outcomes of the study revealed that a substantial number of science high school students have misconceptions concerning acceleration in pendulum motion, and that many of them do not understand the relationship between force and acceleration. In addition, the results of the study showed that more than 30% of the students drew the path of a bob going along the tangential direction at the highest point of the motion, and approximately 20% of them drew the path of a bob falling straight down at the lowest point of the motion.

• Journal of The Korean Association For Science Education
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• v.27 no.7
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• pp.592-608
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• 2007

This study explored the types of conceptual change of 'force' within middle school students' conceptual ecologies. This qualitative study was implemented with the use of classroom observations and two interviews with the participants. 11 middle school students (7 females and 4 males) joined in this study. The interviews with the participants were conducted individually before and after the 'force' unit. The collected data were all transcribed and analyzed interpretively. The results of this study consisted of two parts. First, the participants' conceptual ecologies of 'force' were categorized into 4: epistemological commitments (fixed or interactional explanatory consistency), analogy (attribute, working), metaphysical beliefs (people-oriented ontology, animism, causationism, mixed), and past experiences. Second, two representative cases including 'stable' and 'transitional' states were explained based on the interactions within their own conceptual ecologies. We can see students' conceptions with the integrated perspective in the sense that this results tried to get contextual and interactional understandings of the status of the conception and the possibilities of conceptual change. In addition, it implied that conceptual change research should have the perspective of conceptual ecology evolution in the future.