• 한국과학교육학회지
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• 제24권3호
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• pp.583-595
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• 2004

본 연구의 목적은 초등학생들의 힘에 대한 개념이 연모 실험을 설계하는 과정에 영향을 끼치고 있는 가를 탐색적으로 분석하는 것이다. 초등학교 6학년 학생 40명을 대상으로 힘에 대한 개념을 4개의 선다형 문항을 실시하여 응답 유형을 구분하였다. 힘 개념을 조사하는 문항과 짝을 이루도록 개발된 연모 실험의 4가지 과제를 동일한 학생들에게 해결하도록 하여 실험 설계 능력 중 가설 설정, 변인 통제 및 실험 방법의 요인으로 구분하여 조사하였다. 연구의 분석 결과 초등학생들을 힘에 대한 개념을 과학적 개념과 대안적 개념 집단으로 구별될 수 있었으며, 그 개념에 따라서 실험 설계 능력 중 가설 설정과 변인 통제 및 실험 방법에서 어떤 유형으로 구별되는 가를 분석하였는데, 과학적인 힘 개념을 가진 학생들이 연모 실험의 가설 설정과 변인 통제 및 실험 방법에서 차이를 보이지 못하였다. 이런 결과는 초등학생들의 힘 개념이 연모 실험을 설계하는데 아무런 영향을 주지 못하며, 결국 과학 개념이 실험을 설계하는데 긍정적인 역할을 하도록 한다는 가정이 유지되기 어렵다는 점을 시사받을 수 있었다.

• 한국과학교육학회지
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• 제17권4호
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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.

• 한국과학교육학회지
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• 제26권7호
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• pp.805-812
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• 2006

본 연구에서는 끓는점 오름에 대한 고등학교 화학 교과서의 기술 양식과 고등학생, 예비교사, 고등학교 화학교사의 이해에 대하여 조사하였다. 6차와 7차 교육과정에 근거하여 개발된 고등학교 화학 II 교과서를 분석하였고 고등학생과 예비교사, 화학교사의 개념은 설문지를 통해 얻었다. 끓는점 오름의 원인에 대한 교과서의 설명 유형은 '표면의 용매 입자수의 감소', '용매-용질간의 인력', 그리고 '표면 입자수의 감소와 용매-용질간의 인력'등의 세 가지 유형으로 분석되었다. 개념조사 결과 '용매-용질간의 인력'을 끓는점 오름의 원인으로 인식하는 학생과 예비교사, 화학교사의 비율이 높았다. 대상자들은 끓는점 오름을 설명하기 위하여 엔트로피 개념보다 엔탈피 개념을 선호하는 경향이 있었고, 그 원인을 분석하기 위하여 사후 인터뷰를 실시하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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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.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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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.

• 한국과학교육학회지
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• 제7권2호
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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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• 제7권1호
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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.

• 영어영문학
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• 제57권6호
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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.

• 한국과학교육학회지
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• 제26권5호
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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.

• 한국과학교육학회지
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• 제27권7호
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• pp.592-608
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• 2007

이 연구에서는 힘 개념에 대한 중학생의 개념생태 요소를 탐색하고 개념변화의 사례를 살펴보는 데 그 목적이 있었다. 연구는 질적 방법을 사용하였으며, 수업관찰과 면담으로 수행되었다. 연구 참여자는 중학생 11명으로 여학생 7명과 남학생 4명이었다. 면담은 힘단원의 수업 시작 전 사전 검사와 2차레 개별 심층 면담으로 이루어졌다. 수집된 자료는 모두 전사되고 해석적으로 분석되었다. 연구 결과는 두 부분으로 기술되었다. 첫째, 연구 참여 학생들의 힘 개념을 구성하는 개념생태는 크게 인식론적 확신근거(일방향 및 상호작용적 설명 일관성), 비유(속성, 작용), 형이상학적 신념(인간중심의 존재론, 물활론, 인과적 추론, 혼합형), 과거 경험의 네 범주로 분류할 수 있었다. 둘째, 학생들의 개념변화의 대표적인 유형으로, 개념의 안정 상태와 개념변화로의 과도기 상태를 보여주는 사례를 제시하였고, 개념생태의 특정을 살펴보았다. 이 연구의 결과는 중학생의 힘 개념의 위치와 변화 가능성에 대하여 개념생태를 통하여 구조적이고 상호 연관적 이해를 추구한다는 점에서 기존 연구 결과를 통합적 관점에서 볼 수 있도록 해 준다. 뿐만 아니라 개념생태의 진화적 관점으로 개념 변화를 추구해야 할 것으로 시사한다.