• 한국수학교육학회지시리즈A:수학교육
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• 제41권3호
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• pp.341-360
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• 2002

The purpose of the study was to investigate the effectiveness of dynamic software in solving high school analytic geometry problems compared with traditional algebraic approach. Three high school students who have revealed high performance in mathematics were involved in this study. It was considered that they mastered the basic concepts of equations of plane figure and curves of secondary degree. The research questions for the study were the followings: 1) In what degree students understand relationship between geometric approach and algebraic approach in solving geometry problems? 2) What are the difficulties students encounter in the process of using the dynamic software? 3) In what degree the constructions of geometric figures help students to understand the mathematical concepts? 4) What are the effects of dynamic software in constructing analytic geometry concepts? 5) In what degree students have developed the images of algebraic concepts? According to the results of the study, it was revealed that mathematical connections between geometric approach and algebraic approach was complementary. And the students revealed more rely on the algebraic expression over geometric figures in the process of solving geometry problems. The conceptual images of algebraic expression were not developed fully, and they blamed it upon the current college entrance examination system.

• 한국정밀공학회지
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• 제21권2호
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• pp.210-217
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• 2004

In this study, a new process, named as nano replication printing(nRP) process, is developed for printing any figure in the range of several micrometers by using voxel matrix scanning scheme. In this newly developed process, a femto-second laser is scanned on a photosensitive monomer resin in order to induce polymerization of the liquid resin according to a voxel matrix which is transformed from bitmap format file. After the polymerization, a droplet of ethanol is dropt to remove the unnecessary remaining liquid resin and then the polymerized figures with nano-scaled precision are only remaining on the glass plate. By the nRP process, any figure file of bitmap format could be reproduced as nano-scaled precision replication in the range of several micrometers. Also, nano/micro-scaled patterns for an extremely wide range of applications would become a technologically feasible reality. Some of figures with nano-scaled precision were printed in scaled replication as examples to prove the usefulness of this study.

• 소성∙가공
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• 제29권1호
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• pp.27-36
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• 2020

The Goss texture component of {110}<001> is well known as one of the best texture components to improve the magnetic properties of electrical steel sheets. The small amount of the Goss texture component is obtained at the surface of the steel sheet by shear deformation due to friction between the steel sheet and the roll during conventional symmetric rolling. This study aims to identify a method to obtain high intensity of the Goss texture component not only at the surface but in the whole layer of the steel sheet by shear deformation of asymmetric rolling. Low carbon steel sheets, which have different initial texture, were asymmetrically rolled by about 50%, 70%, and 80%. The pole figures of the top, center, and bottom layers of the initial and asymmetrically rolled low carbon steel sheets were measured by an X-ray diffractometer. Based on the measured pole figures of these samples, the intensities of the main texture components were analyzed for the initial and asymmetrically rolled low carbon steel sheets. As a result, the initial low carbon steel sheet with the γ-fiber component showed a higher intensity of the Goss texture component in the whole layer than the steel sheet with other texture components after asymmetric rolling.

• 한국해양공학회지
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• 제25권3호
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• pp.47-52
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• 2011

3D geometric modeling has a lot of advantages in the field of design and manufacturing. Many manufacturing processes and production lines are using 3D geometric modeling technique. These help reduce the cost and time for manufacturing. The purpose of this study is the realization of a 3D cutting shape for an H-Beam used in ships and ocean plants. The complex 3D cutting shapes could be represented by using the boolean operation of basic figures. Graphic functions with parameters were used to simply define the basic figures. The developed system can show the complex cutting shape of an H-beam simply and quickly. This system can be utilized for the automatic cutting system for an H-beam.

• Ocean and Polar Research
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• 제24권4호
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• pp.501-524
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• 2002

Article 121 of the UNCLOS stipulates the regime of islands and grants different jurisdictions to islands and rocks. Especially, paragraph 3 gives different definitions and distinguishes the legal status of between islands and rocks. That is, rocks, which cannot sustain human habitation or economic life cannot have their own EEZ, continental shelf or the great-sphere maritime jurisdiction. In this paper various theories and state practicess on islands and rocks are examined with reference to Article 121 of UNCLOS. Also, the status of Dokdo as a rock or an island is examined in accordance with the interpretation of Article 121 of UNCLOS. National legislations, practices, and many scientific opinions are often contradictory and controversial with respect to the interpretation of Article 121 of the UNCLOS. However, it is believed that Article 121 of UNCLOS, particularly paragraph 3 has to be interpreted more strictly. That is because the highly developed modem scientific technology can be meaningless when the criteria of Article 121 of UNCLOS are to be inappropriately applied. Insular figures like ${\ulcorner}rocks{\lrcorner}$ could bring the inequitable effects disadvantageous toward the other party when the maritime delimitation is applied. Claiming and Intentionally extending maritime zone of a coastal states by assigning EEZ for small insular figures like ${\ulcorner}rocks{\lrcorner}$ is over-zealous nationalism which is illegal, and such practices must be recognized as actions bringing great harm to the neighboring nations and demise of the sprit of all mankind.

• 정보교육학회논문지
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• 제14권3호
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• pp.395-404
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• 2010

수학 교육이 해결해야하는 과제 중 하나는 학습 부진아 문제이다. 이러한 문제를 개선하고 효율적인 학습 부진아 지도를 위해 '도형아 놀자'라는 교수.학습 시스템을 개발하였다. 도형아 놀자 교수학습 시스템은 학습 부진아의 수준에 맞는 맞춤식 교육을 목표로 도형영역의 내용을 5단계로 재구성하였다. 이를 바탕으로 학습부진아에게 도형에 대한 흥미 및 자기 주도적 학습 능력을 길러주기 위해 학년 구분 없이 수준에 따라 재구성하고 학습 부진아들이 자기 수준에 맞는 단원을 선택하여 스스로 문제를 해결해갈 수 있도록 시스템을 구성하였다.

• 무역학회지
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• 제45권1호
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• pp.47-64
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• 2020

For the past few years, the Korean government has been consistently expanding its national research & development budget to accelerate economic growth through technology innovation and the enhancement of international competitiveness in global markets. The objective of this paper is to define the concept and analyze the current status of national R&D programs by measuring R&D efficiencies. We determine R&D efficiency by reflecting inputs and outcomes of the five main agricultural R&D programs between 2010 to 2015, and by categorizing and regrouping figures that may affect R&D performance. Among 1,128 targeted projects, 832 projects with patents and thesis were selected for analysis in terms of measuring technology efficiency, pure technology efficiency, and efficiency of scale. Also, the Kruskal-Wallis test was also utilized as well. As a result of empirical analysis, figures that affected the efficiency level of national R&D programs included differences in research resources, research management levels and skills, and research field. This study can be utilized as a reference for re-establishing national agricultural R&D policies, such as enhancement of national technology competitiveness in the global market environment, improving and adapting to new agricultural conditions, market expansion, national agricultural R&D efficiency, aging rural population, agricultural management cost increase, and climate change mitigation.

• 한국응용곤충학회지
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• 제19권3호
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• pp.149-152
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• 1980

국내에서 채집된 Pagaronia속 매미충을 분류동정하여 새로이 P. kumsanensis(금산황백매미충), P. heuksanensis(흑산황백매미충), P. hamatus(갈구리황백매미충)의 3신종을 추가하였다.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.41-44
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• 2006

In the field of launch vehicle development, aerodynamic design means an overall management about external appearances. At least, related to outer figures of the launch vehicle, aerodynamic design has the initiative activities. For that reason, in this report, aerodynamic design techniques and application methods will be introduced.

• 한국수학사학회지
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• 제14권2호
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• pp.115-124
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• 2001

In this paper, we developed a Web application program that could show the shape, the number of the vertices, the edges, the faces and development figures of polygons(regular tetrahedron, regular hexahedron, etc). The program was implemented using GSP(Geometer's SketchPad) and then converted to JAVA to display the results of GSP on the Web. The results of this paper are applicable to geometry of a junior high school course.