• 한국전산구조공학회논문집
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• 제30권6호
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• pp.531-539
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• 2017

전통적인 FRP 선체 제작에는 mould가 요구되며, mould의 높은 제작비용은 FRP 선박 제작자에게 비용부담을 주고 있다. 이를 극복하기 위한 방안으로 강선 건조에서 사용되는 블록 혹은 모듈 방식의 제작기법에 착안한 modular construction 방안이 제시되었다. 이 제작방안을 FRP 선체에 효율적으로 적용하기 위해서는 설계 및 제작 측면에서 간략하면서도 구조적 안정성을 갖는 접합 이음부 개발이 이루어져야 한다. 따라서, 본 논문에서는 모듈방식의 FRP 선체 제작을 위해 moulding-in 개념을 기반으로 한 경제적인 접합 이음부 개발에 관한 연구를 수행하였다. FRP 샌드위치 판을 대상으로 step, scarf-step 그리고 scarf 이음부 형상을 갖는 moulded-in을 수지주입식진공성형 공정에 도입하여 성공적으로 접합된 FRP 샌드위치 판을 제작하였다. 이에 대해 구조적 안정성 평가를 목적으로 인장 및 4점 굽힘 시험 그리고 유한요소해석을 수행하였다. 시험과 해석결과에 대한 비교 연구를 통해 본 연구에서 개발된 접합 이음 내용이 모듈방식의 FRP 선체 제작에 적용 가능함을 확인할 수 있었다.

• 디자인학연구
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• 제13권
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• pp.153-162
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• 1996

최근의 경제성장과 아울러 우리의 주거 공간이 보다 더 확장되어 가는 추세에 있다. 따라서 PAC (PACKAGE AIR CONDITIONER) 가 종래에는 주로 업소 설치용으로 판매되었으나 최근에는 하절기 상품으로써 생활수준의 향상과 함께 업소용에서 가정용으로 옮겨가는 상태에 있다고 볼 수 있다. PAC는 최근의 기후 온난화 현상에도 영향을 받아 날로 그 수요가 늘어나고 있으며 필수품 화되어 가는 추세에 있다. 본 연구는 국내에 대표적인 가전 업체인 (주)금성사에서 추진 개발되었던 PAC의 제품개발과 DESIGN PROCESS에 대한 사례 연구로서 기업에서의 제품개발과 디자인이 어떠한 연구와 과정을 통해 이루어지는가에 대해 고찰에 보았으며 이러한 연구과정을 토대로 조형화(가사 화) 시키는데 역점을 두었다. 예컨대 우선 하절기 상품인 만큼 기후에 따른 한국인의 체질과 그 특수성을 알아보았으며 고객 환경으로써 PAC의 표적고객을 설정하여 그 수요를 예측해 보았다. 고객 환경으로써 PAC의 표적고객을 설정하여 그 수요를 예측해 보았다. 그리고 PAC와 직접적인 관계가 있는 주거환경으로써 APT 거주지의 거실에서의 행위를 분석하였으며 아울러 거실의 전반적인 INTERIOR IMAGE를 분석하여 PAC의 조형화 작업에 일조를 하였다. 실질적인 조형화 작업에 있어서는 DESIGN CONCEPT을 고객환경, 주거환경, 제품 환경으로 나누어 다음과 같이 추진하였다. 첫째. 성 SPACE화로써 설치공간의 극소화 및 시각적 개방 감을 유도하는 NEW SHAPE(ROUND SLIM)을 구현하였고 둘째. INTERIOR화로써 거실의 분위기와 조화되는 제품의 고급 감을 표출하였다. 셋째. HIGH-TOUCH화로 사용자의 감성을 자극하는 SHAPE 및 표면 처리에 역점을 두었고 넷째로, HI-QUALITY화로써 전자제품에서 보여지는 TECHNOLOGY IMAGE의 과감한 도입적용을 시도하였다.

• Korea-Australia Rheology Journal
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• 제20권1호
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• pp.7-14
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• 2008

The objective of this work is to propose a procedure to simulate the flow in the LCM (Liquid Composites Molding) processes by finite difference discretization in a curvilinear coordinate system adapted to the shape of the saturated zone. The numerical results obtained are compared with experimental results obtained by an experimental device elaborated at our laboratory. It allows to realize linear and radial injections for different porosities and to observe the flow front kinetics. Numerical and experimental results are then compared with those of the literatures and excellent agreements are noticed. Finally, we suggest a concept of the capillary number to explain the variations of the permeability obtained for pressure values lower than 0.25 Bar.

• 한국수학교육학회지시리즈A:수학교육
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• 제24권2호
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• pp.105-116
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• 1986

For any thought and knowledge, its growth and development has close relation with the society where it is developed and grow. As Feuerbach says, the birth of spirit needs an existence of two human beings, i. e. the social background, as well as the birth of body does. But, at the educational viewpoint, the spread and the growth of such a thought or knowledge that influence favorably the development of a society must be also considered. We would discuss the goal and the function of mathematics education in relation with the prosperity of a technological civilization. But, the goal and the function are not unrelated with the spiritual culture which is basis of the technological civilization. Most societies of today can be called open democratic societies or societies which are at least standing such. The concept of rationality in such societies is a methodological principle which completes the democratic society. At the same time, it is asserted as an educational value concept which explains comprehensively the standpoint and the attitude of one who is educated in such a society. Especially, we can considered the cultivation of a mathematical thinking or a logical thinking in the goal of mathematics education as a concept which is included in such an educational value concept. The use of the concept of rationality depends on various viewpoints and criterions. We can analyze the concept of rationality at two aspects, one is the aspect of human behavior and the other is that of human belief or knowledge. Generally speaking, the rationality in human behavior means a problem solving power or a reasoning power as an instrument, i. e. the human economical cast of mind. But, the conceptual condition like this cannot include value concept. On the other hand, the rationality in human knowledge is related with the problem of rationality in human belief. For any statement which represents a certain sort of knowledge, its universal validity cannot be assured. The statements of value judgment which represent the philosophical knowledge cannot but relate to the argument on the rationality in human belief, because their finality do not easily turn out to be true or false. The positive statements in science also relate to the argument on the rationality in human belief, because there are no necessary relations between the proposition which states the all-pervasive rule and the proposition which is induced from the results of observation. Especially, the logical statement in logic or mathematics resolves itself into a question of the rationality in human belief after all, because all the logical proposition have their logical propriety in a certain deductive system which must start from some axioms, and the selection and construction of an axiomatic system cannot but depend on the belief of a man himself. Thus, we can conclude that a question of the rationality in knowledge or belief is a question of the rationality both in the content of belief or knowledge and in the process where one holds his own belief. And the rationality of both the content and the process is namely an deal form of a human ability and attitude in one's rational behavior. Considering the advancement of mathematical knowledge, we can say that mathematics is a good example which reflects such a human rationality, i. e. the human ability and attitude. By this property of mathematics itself, mathematics is deeply rooted as a good. subject which as needed in moulding the ability and attitude of a rational person who contributes to the development of the open democratic society he belongs to. But, it is needed to analyze the practicing and pursuing the rationality especially in mathematics education. Mathematics teacher must aim the rationality of process where the mathematical belief is maintained. In fact, there is no problem in the rationality of content as long the mathematics teacher does not draw mathematical conclusions without bases. But, in the mathematical activities he presents in his class, mathematics teacher must be able to show hem together with what even his own belief on the efficiency and propriety of mathematical activites can be altered and advanced by a new thinking or new experiences.