• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.2
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• pp.101-106
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• 2006

The optimum design of turbine blade at minimized fatigue life can be derived by the statistical fatigue analysis in this study, The optimum value of positions in the axes of X and Y at turbine blade can be found by design of experiments on the condition that the value of fillet radius is fixed to minimize the fatigue life. The degree of uncertainty about process at the factors in the axes of X and Y can be calculated by six sigma analysis. The optimum value of fillet radius is determined by utilizing the robust design at uncertain condition. It is concluded that maximum von Mises stress can decreased by 20% and the fatigue life can be double.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.3
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• pp.765-770
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• 2008

Ji, Syok-young wrote a book named Sinhaksinseol(新學新說) in 1891, one of the first hygiene books in Korea. There were the conditions of modern housing like lighting, ventilation and dry and fresh air of a housing site in the contents of the book. Because the book was written when the modern hygiene theory had just been accepted, traditional concept of 'Yangseng(養生),' but it dealt the main environmental conditions of hygienic housing at first, which makes it the leader of modern housing discourses through the newspapers, magazines, academic journals or textbooks from 1890s mid to 1910.

• Journal for History of Mathematics
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• v.21 no.2
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• pp.1-18
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• 2008

As a sequel to the previous paper Gou Gu Shu in the 18th century Chosun, we study the development of Chosun mathematics by investigating that of Gou Gu Shu in the 19th century. We investigate Gou Gu Shu obtained by Hong Gil Ju, Nam Byung Gil, Lee Sang Hyuk and Cho Hee Soon among others and find some characters of the 19th century Gou Gu Shu in Chosun.

• 대한공업교육학회지
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• v.36 no.1
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• pp.75-94
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• 2011

The purpose of this study is to suggest the basic data in order to examine and perform the plan for activating the team teaching between industry-educational adjunct teachers and vocational teachers in technical high school. The research results are as follows. First, It is found that both teacher groups acknowledge the necessity of the team teaching, but vocational teachers are less likely to recognize the necessity than industry-educational adjunct teachers. Second, In the preparation of team teaching, both two groups of the teachers believe that the preliminary interchange and training between them are to be highly supportive for the activities expected to help teachers. Therefore, it is necessary to have opportunity of communication and narrow the difference of opinions between them by promoting the deep interest about applicable field and sharing the mutual idea between the teachers in the preparation of team teaching. Third, And the two groups recognize that the cooperation and joint establishment of design of team teaching and the individual process or joint progress of class activity are desirable for the proper design of team teaching. Therefore, it is necessary to establish the class environment for the interaction between teachers and students through not only the reciprocal activities between teachers but the interest class by systematically preparing the class design and role division clearly. Fourth, In the practice of team teaching, the two groups believe that the teaching activities can be usually divided and progressed, but it is desirable to work together in the related contents. The vocational teachers recognize that it is necessary to actively interact with students by connecting with the case of industry field. On the other side, industry-educational adjunct teachers think that the learning contents should be selected and organized according to the interests of students by associating with the case of industry field. Fifth, And two groups of teachers recognize that it is desirable to evaluate the grade by reflecting on the assessment by vocational teachers(50%), industry-educational adjunct teachers(50%).

• The Mathematical Education
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• v.61 no.1
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• pp.47-62
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• 2022

This study investigated the contents related to the plane figures in the geometry domains of Joseon-Sanhak in the late 18th century and focused on changes in explanations and calculation methods related to plane figures, the rigor of mathematical logic in the problem-solving process, and the newly emerged mathematical topics. For this purpose, We analyzed , and written in the late 18th century and and written in the previous period. The results of this study are as follows. First, an explanation that pays attention to the figures as an object of inquiry, not as a measurement object, and a case of additional presentation or replacing the existing solution method was found. Second, descriptions of the validity of calculations in some problems, explanations through diagrams with figure diagrams, clear perceptions of approximations and explanations of more precise approximation were representative examples of pursuing the rigor of mathematical logic. Lastly, the new geometric domain theme in the late 18th century was Palsun corresponding to today's trigonometric functions and example of extending the relationship between the components of the triangle to a general triangle. Joseon-Sanhak cases in the late 18th century are the meaningful materials which explain the gradual acceptance of the theoretical and argumentative style of Western mathematics

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.43-51
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• 2016

Preventing the forgery and alteration of test reports is important, in order to maintain the reliability of military supplies. Based on a survey of reports on testing institutions and a case study of established electronic document systems in the public sector, we propose a system architecture, which helps prevent the forgery and alteration of test reports with legal force. The proposed architecture takes advantage of both the time stamp that records the time a document is received and a server synchronized with the testing institution. Using the proposed system architecture, the user is able to request a test and receive reports from the testing institution without delay. Also, a defense agency is able to conveniently prove the authenticity of the test reports and utilize the statistical data collected by the architecture. Therefore, we expect that the proposed system architecture will help defense agencies to prevent the forgery and alteration of test reports and ensure their reliability and quality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.7
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• pp.3022-3029
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• 2011

One of the characteristics of the informatics subject implementing the revised national curriculum is to develop the practical attitude of the student as an active member of information society. The purpose of this study is to examine whether the units 'Information Society and IT' in middle school informatics textbooks reflect inquisitive tendencies to student's practice. After four textbooks that were widely selected by schools were selected from among the authorized textbooks, the sentences of the selected textbooks were analyzed by utilizing Romey's analysis method to see whether there was such an inquisitive tendency in them. As a result of analyzing six content elements of the textbooks, one textbook and two textbooks had an inquisitive tendency in three elements or more in terms of texts and activities index respectively. But there was no inquisitive tendency in the textbooks in terms of figure/diagrams, questions at the end of chapters and chapter synthesis. This study is meaningful in that it attempted to make a quantitative analysis of middle school informatics textbooks and to investigate an inquisitive tendency in the textbooks by analyzing every statement and sentence instead of analyzing just some parts of the textbooks.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3582-3588
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• 2013

Expressed sequence tag (EST) library was constructed from A. tamarense. Base sequences of EST clones were analyzed and saxitoxin biosynthesis-related genes were cloned. Sequences of 827 clones were analyzed and 564 EST were functionally clustered using Blast searches against GenBank. Main genes in the EST had functions on cellular organization, cell metabolism, energy, cell cycle and DNA processing, cellular transport and transport, cell rescue, defense, death and aging, and transcription. Moreover, expression of S-adenosylmethionine synthetase and H2A histone family genes were increased in the toxic A. tamarense. These results show that two genes could be a good biomarkers for the detection of saxitoxin biosynthesis in the A. tamarense.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.231-240
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• 2016

Recently, fake test data of power cables in nuclear power plants was a terrible shock to the citizens. Some cable companies manipulated the test data to make unfair profits. In addition, fake test data cases were found in military supplies. The fake test data cases focused on parts of army's tank, armored car. This paper propose a new method that can detect fake test data using known statistical methods. In addition, the method was implemented in Microsoft Excel to allow easy use. Lastly, a check sheet was proposed to check the validity of the test system of military suppliers. By detecting and checking the fake test data, it is expected that our new method will play an important role in quality assurance of military supplies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.423-431
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• 2016

The purpose of this study was to analyze and compare the characteristics of floor plan of Underwood hall, Appenzeller hall, and Stimson hall in Yonsei University. These buildings in Yonsei University are the representative higher educational institution buildings that were constructed by Western missionaries during the Japanese colonial period. These buildings were designed by the master plan that had been made before the construction. Therefore, these buildings have many similarities but each building has individual characteristics. This study focused on two parts. One is the characteristics of the shared space, such as like corridor, hall, and stairs. These characteristics show the differences between each building because they used different methods and locations of shared space and rooms for the floor plan to include the different functions. The second is the relationships with the floor plan and other plans like the master plan, elevation plan, and structural plan. These relationships show that each building has unique characteristics that are related to the floor plan.