• Korean Institute of Interior Design Journal
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• v.20 no.6
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• pp.145-152
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• 2011

Salvador Dali put a title of his work as 'A Propos of the Treatise on Cubic Form by Juan de Herrera' at 1960. Through this work which is consisted in cube frame surrounding black and white letter squares and nails in the sky, he directly referred about the cube which were showed in his pictures. To understand the meaning of this work, Dali's paintings and Juan de Herrera's design and architectural ideas are analysed by building. His concerning about absolute existence like god and nuclear takes the cubic form by Juan de Herrera instead of pictorial tendencies of Cubism, however pictorial elements such as sky and nails were still used in the work. He use alphabet letter as pattern consisting wall and symbol representing 'Juan de Herrera', moreover number '2' is taken to show up line attribute. Dali had several design develop process, and finally he reached an new stage called 'Hypercube'. Hypercube can distinguish from Cubism and Herrera's architectural idea, and it will be free from objective world based in Euclid geometry. Although cubic is the simplest shape. It can contain the variety of developments in these fields - philosophy, architecture, painting and etc.- from Platon to nuclear physics and coexists in a picture of Salvador Dali.

• Journal of Power Electronics
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• v.14 no.1
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• pp.92-104
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• 2014

To insure stable operation and eliminate twice torque ripple, a topology for a six phase permanent magnet synchronous generator (SP-PMSG) with a neutral point connected together was analyzed in this paper. By adopting an extended transformation matrix, the mathematic model of the space vector control was established. The voltage and torque equations were deduced while considering the third harmonic flux and inductance. In addition, the suppression third harmonic method and the closed loop control strategy were proposed. A comparison analysis indicates that the cooper loss minimum method and the current magnitude minimum method can meet different application requirements. The voltage compensation amount for each of the methods was deduced which also takes into account the third harmonic effect. A simulation and experimental result comparison validates the consistency through theoretical derivation. It can be seen that all of the two control strategies can meet the requirements of post-fault.

• Journal of The Korean Association of Information Education
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• v.19 no.3
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• pp.271-278
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• 2015

This study proposed new approach for the information gifted discrimination test using EPL. We tried to distinguish high level thinking in the information gifted through test of this study. We categorized testing tool according to context type: simple attribute problem, complex same attribute problem, complex focus attribute problem, mathematic-verbal ability required problem. And testing tool divided into modifying scripts, guess scripts's result, using scratch program. In the effectiveness test of proposed tool, we confirmed content validity and credibility.

• The Journal of Information Systems
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• v.5
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• pp.21-41
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• 1996

Linear programming has become an important tool in decision-making of modern business management. This remarkable growth can be traced to the pioneering efforts of many individuals and research organizations. The popular using of personal computers make it very easy to process those complicated linear programming models. Furthermore advanced linear programming software packages assist us to solve L.P. models without any difficult process. Even though the advanced L.P. professional packages, the needs of more detailed deterministic elements for business decisions have forced us to apply dynamic approaches for more resonable solutions. For the purpose of these problems applying to the "Mathematica" packages which is composed of mathematic tools, the simplex processes show us the flexible and dynamic decision elements included to any other professional linear programming tools. Especially we need proper dynamic variables to analyze the shadow prices step by step. And applying SAS(Statistical Analysis System) packages to the L.P. problems, it is also one of the best way to get good solution. On the way trying to the other L.P. packages which are prepared for Spreadsheets i.e., MS-Excel, Lotus-123, Quatro etc. can be applied to linear programming models. But they are not so much useful for the problems. Calculating simplex tableau is an important method to interpret L.P. format for the optimal solution. In this paper we find out that the more detailed and efficient techniques to interpret useful software of mathematica and SAS for business decision making of linear programming. So it needs to apply more dynamic technique of using of Mathematica and SAS multiple software to get more efficient deterministic factors for the sophiscated L.P. solutions.

• Journal of the Korea Fashion and Costume Design Association
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• v.12 no.1
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• pp.35-49
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• 2010

The Imwon Sipyukji of this study was compiled by Seo Yugu (1764~1845), a famous agronomical scholar of the late eighteenth century. The contents of this book are divided into sixteen chapters related to all the important parts of rural home life ranging from daily routines to social life covering the agro-industry and the six skills of manners, music, archery, calligraphy, mathematics and horseback riding. Seomyongji, one of the sixteen chapters, covers all that is necessary for living a rural existence such as house-building, clothing adornments and transportation as well as how to make and use daily household items. The contents of the Boksik Jigu sub-section in the Sumyongji chapter consist of eight large units covering men's and women's clothing, bedding and pillows, sewing tools, belt and shoes accompanying the attire and storage for clothes. These eight are further subdivided into 65 items, each warranting a detailed explanation. My study will translate the original Chinese text of Boksik Jigu into Korean. This sub-section in the Seomyongji chapter will facilitate an investigation into the information contained therein on attire and accessories.

• Communications of Mathematical Education
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• v.13 no.2
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• pp.751-764
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• 2002

미국의 “전국 수학 교사 협의회” (National Council of Teachers of Mathematics, NCTM)는 1989년부터<학교 수학의 교육과정과 평가 규준> (1989), <수학 가르침(교수)의 전문성 규준> (1991), <학교 수학의 평가(시험) 규준> (NCTM, 1995), <학교 수학의 원리와 규준> (2000)을 출판하여 미국의 수학 교육의 전망(목표, 나아갈 길)과 규준(실행 지침)을 제시하였다. 수학 교사들로 구성된 미국의 NCTM은 학생, 학부모, 학교 행정가 등 많은 사람들과 힘을 합하여 모든 학생들에게 수준 높은 수학 교육을 받을 수 있는 여건(환경, 기회)을 조성하는 데 구심점의 역할을 하였다. 한편 많은 관련 단체들은 여러 배경과 능력을 가진 학생들이 전문성을 지닌 교사(특수 교사를 일컫는 말이 아니다. 수학 교과를 이해하고 수학의 전문성과 특수성을 가르칠 수 있는 일반 교사를 일컫는 말이다.)로부터 미래를 대비해 평등하고, 진취적이며, 지원이 잘 이루어지고, 공학 도구(IT)가 잘 갖춰진 환경에서 중요한 수학적 아이디어를 이해하면서 학습할 수 있는 수학 교실(미국에서는 우리나라처럼 수학 교사가 수학 시간에 학생의 방(교실: Homeroom)에 찾아가지 않고 학생들이 선생의 방(수학 교실: Classroom)을 찾아온다. 전형적인 수학 교실의 사진은 2쪽에 나와 있다.)을 만들기 위해 함께 힘썼다. NCTM에서 출간한 여러 규준들은 우리나라의 제 6 차와 제 7 차 교육과정에도 큰 영향을 미쳤다. 이 글에서는 NCTM (2000)에서 제시한 학습 원리를 간단히 살펴본 다음 이를 중심으로 현재 미국 수학교육의 교수 ${\cdot}$ 학습 이론의 동향을 살펴본다.

• Education of Primary School Mathematics
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• v.11 no.2
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• pp.105-119
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• 2008

Functional thinking, which focuses on the relationship between two or more varying quantities, is one of the key strands of algebraic thinking. This article is a case study that aimed to investigate how 3rd grade elementary students might make their functional thinking. The results showed that students not only understood the functional situation well but also created a record of the corresponding values of quantities, typically using descriptive writings and pictures. But when they tried to find a pattern and make a generalization, the students showed various difficulties. This paper concludes with implications on how to promote students' functional thinking from early grades in the elementary school.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.531-536
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• 2005

The purpose of this paper is to improve the hysteresis characteristics of a stack type piezoelectric actuator using system identification and tracking control. Recently, several printing methods that cost less and are faster than previous semiconductor processes have been developed for the production of electric paper and RFID. The system proposed in this study prints by spraying the molten metal, and consists of a nozzle, heating furnace, operating actuator, and an XYZ 3-axis stage, As an operating system, the piezoelectric(PZT) method has very valuable uses. However, the PZT actuator has a very big hysteresis characteristic due to the ferroelectric characteristics of the PZT element. This causes problems in the system position control characteristics and deteriorates the performance of the system. In this study, an investigation was conducted to improve the hysteresis characteristics of the PZT actuator that has an output displacement for the input voltage. The study proposed a inverse hysteresis model, a mathematic modeling method that can express the geometric relationship between voltage and displacement, in order to reduce the hysteresis of the PZT actuator. In addition, system identification and PID control methods were examined. Also, it was confirmed that the proposed control strategy gives good precision position control performance.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.5
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• pp.59-65
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• 2009

Adsorption of an oil-proof agent (OPA）onto cellulose fibers during the papermaking process was investigated using UV-Vis spectrophotometry by measuring the OPA concentration decrease in the solution. From the calibration curve, the spectrum were converted to chemical concentrations in solution, from which the amount adsorbed onto the fiber surface could be determined. Thus, it was possible to determine the total amount adsorbed onto the fibers and in solution. Using this approach, we studied the adsorption behavior of the OPA onto the fiber surface and derived its, ${\Gamma}^s_t={\Gamma}^s_{\infty}(1-e^{-k_{\alpha}t})$. The values of the parameters kaand ${\Gamma}^s_{\infty}$ were determined using a mathematic model based on a mass transfer equation. Ultimately, a complete was derived: $Q={\alpha}{\cdot}\sum\limits_{i-1}^m{\pi}d_il_i{\cdot}M_A{\cdot}(1-e^{-k_{\alpha}t})/A_N$.

• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.120-126
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• 1997

The thermal decomposition of low density polyethylene(LDPE) and $25\%{\~}48\%$ chlorinated polyethylene(CPE) were studied using a dynamic thermogravimetry in the stream of nitrogen gas with 20ml/min. The mathematic method, differential (Friedman) and Integral (Ozawa) method were used to obtain value of activation energy of decomposition energy on the reaction. The activation energies evaluated by the above methods agree with each other very well. The maximum average activation energy calculated was 71.71kcal/mol. The thermal decomposition of LDPE and CPE were considered to be carried out by main chain scission and the thermogravimetric trace curve agree with the theoretical equation.