• Title/Summary/Keyword: 자유고

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Homolytic Reactions of Isonitriles (이소니트릴의 자유라디칼반응)

  • Sung Soo Kim
    • Journal of the Korean Chemical Society
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    • v.24 no.3
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    • pp.250-258
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    • 1980
  • Various radicals may add to isonitriles to give imidoyl radcals RN=CR'. This may be also generated via abstraction of imidoyl hydrogen from imine in the following manner: RN=CR' + R"${\cdot}{\rightarrow}$ RN=CR' + R"-H Imidoyl radicals would be stabilized via two pathways, ${\beta}$-cleavage and atom transfer reactions. ${\beta}$-Cleavage may occur in two directions depending upon structure of the radicals. Cyanide transfer and the "so-called" normal ${\beta}$-cleavage are the two modes of ${\beta}$-cleavage. Addition of t-butoxy radical to t-butyl isocyanide 7 generates an imidoyl radical t-Bu-N=C-O-Bu-t, which undergoes ${\beta}$-cleavage to give t-butyl isocyanate and t-butyl radical. Addition of phenyl radical to 7 forms the intermediate radical t-Bu-N=$C-C_6H_5$, which decomposes to give benzonitrile and t-butyl radical. The t-butyl radical generated from the ${\beta}$-cleavage adds to 7 giving the radical t-Bu-N=C-Bu-t, which cleaves only to pivalonitrile and t-butyl radical, inducing radical chain isomerization. Trimethylsilyl radical adds to 7 to give the intermediate t-Bu-N=$C-Si(CH_3)_3$, which collapses to $(CH_3)_3$SiCN and a t-butyl radical.

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A Study on Home Economics Teachers' Perception in Free Learning Semester (자유학기제 운영에 대한 가정과 교사의 인식 분석)

  • Kim, Seong-Sook;Kim, Jung-Hyun;Jung, In-Kyung
    • Journal of Korean Home Economics Education Association
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    • v.29 no.1
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    • pp.111-124
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    • 2017
  • The purpose of this study was to determine the perception and understanding of Free Learning Semester (FLS) in home economics teachers and to provide basic informations for effective implement of FLS in future school curricula. Home economics teachers perceived that the objective of FLS was to help students explore their careers and make preliminary decisions. In addition, teachers thought that FLS should be run by active students' participation to find out their dreams and talents. However, teachers felt difficulties in obtaining information or documents related to implementing FLS. Moreover, there were lack of connected activities with local communities to operate FLS. Teachers recognized that it is necessary to receive FLS-related education. Regarding home economics teachers' role in FLS implement, they should provide career education with a perspective of lifelong career and nurture students' capability to lead their lives by themselves. In that sense, FLS should help students find out their dreams and talents, think about their career, set up lifelong career plan through home economics education, and nurture capability to lead their lives. In addition, home economics teachers should provide continuous career education in home economics education at academic semesters.

Finite Difference Stability Analysis of Anisotropic Plates with Free Edge (자유경계를 갖는 비등방성 판의 유한차분 안정성 해석)

  • Yoo, Yong Min;Lee, Sang Youl;Chang, Suk Yoon
    • Journal of Korean Society of Steel Construction
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    • v.12 no.2 s.45
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    • pp.221-230
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    • 2000
  • Checking the stability of anisotropic plates with free edges, it is impossible that buckling loads and modes are found via existing classical methods about various loads and boundary conditions. For solving this problems. finite difference method(FDM) is used to analyze the buckling behaviors for arbitrary boundary conditions. Using FDM, it is difficult to treat the fictitious points on free edges. So, this paper analyzes buckling behaviors of analytic models with one edge free and the other edges clamped and with opposite two edges free and other two edges clamped. The various buckling loads and mode characteristics through numerical results are given for buckling behaviors of anisotropic plates on free edges.

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Estimation of Interstory Drift for Moment Resisting Reinforced Concrete Frames Using Equivalent SDOF System (등가 1자유도계를 이용한 철근콘크리트 골조건물의 층간변위 응답 산정)

  • Kang, Ho-Geun;Jun, Dae-Han
    • Journal of the Earthquake Engineering Society of Korea
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    • v.8 no.5 s.39
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    • pp.25-33
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    • 2004
  • To evaluate the seismic capacity of a multistorey building structures in performance based seismic design, it is needed to convert MDOF model into equivalent SDOF model. This paper presents predictions for interstory drift of multistorey structures using method of converting a MDOF system into an equivalent SDOF model. The principal objective of this investigation is to evaluate appropriateness of converting method through performing nonlinear time history analysis of a multistory building structures and an equivalent SDOF model. Comparing the interstory drift of multistorey structures calculated by time history analysis and those evaluated by an equivalent SDOF model, the adequacy and the validity of converting method is verified. The conclusion of this study is following; A method of converting a MDOF system into an equivalent SDOF model through the nonlinear time history response analysis is valid. Inelastic first mode shapes are expected to be more accurate than elastic first mode shapes in obtaining interstory drift of multistorey structures from equivalent SDOF model.

A Study on Students' Need for Free Learning Semester Programs of Libraries (도서관의 자유학기제 프로그램에 대한 학생수요조사 연구)

  • Noh, Younghee;Kim, Hyein
    • Journal of Korean Library and Information Science Society
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    • v.47 no.3
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    • pp.187-211
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    • 2016
  • The present study investigates the seventh and the eighth graders' perception of Free Learning Semester Programs offered by libraries by developing a survey questionnaire on students' needs for Free Learning Semester Programs of Libraries. The skills that middle school students want to improve in Free Learning Semesters are career exploration skills, and the type of Free Learning Semester that is most intensively implemented is career exploration activities. Programs are often offered in the form of experiential classes. Regarding the activities that the students want to participate during Free Learning Semester, the most preferred activities included field experience activity in the career exploration domain, cooking class in the student choice program, smartphone app development in club activities, design activity in the art domain, the badminton in the physical education domain, and using iPad in the information use skills. In addition, among the library programs in coordination with Free Learning Semester, the students liked the occupational experience program most. Future studies need to include the development and implementation of Free Learning Semester Programs based on students' opinions, and investigate their satisfaction with the Free Learning Semester Programs offered by libraries.

Numeric Analysis of 2-Dimensional Nonlinear Viscous Free-Surface Wave Problems (점성을 고려한 2차원 비선형 자유표면파 문제의 수치해석)

  • Y.H. Kim
    • Journal of the Society of Naval Architects of Korea
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    • v.30 no.2
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    • pp.98-111
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    • 1993
  • Two-dimensional nonlinear free-surface wave problems are analyzed with consideration of viscosity. Navier-Stokes equation and continuity equation are solved by the application of Finite Analytic Method, and MAC scheme is used far the treatment of free surface. Surface tension effect is also considered and laminar flow is assumed. The free-surface waves in shallow water, the flows around a vortex-pair with free surface and the wave ahead of a rectangular body are simulated to test the present numerical scheme. In the shallow water problem, viscous effect due to the friction on the bottom is observed. In the second problem, the approach of a vortex-pair to the free surface is simulated to examine the interaction of vortex-pair with the free surface. In the third problem, the wave ahead of a semi-infinite floating body is simulated.

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Alternatives for Strengthening the Function of Free Trade Zone in Gwangyang Bay Area (광양만권 자유무역지역의 기능 강화 방안에 관한 연구)

  • Kim, Hyun-Duk
    • Journal of Navigation and Port Research
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    • v.35 no.6
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    • pp.533-538
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    • 2011
  • Recently, Free Trade Area generally moves toward a complex and total zone carrying out the logistics and production function simultaneously. Nevertheless, Free Trade Area of Gwangyang Bay Area performs a traditional logistics function only without a introduction of production function. Therefore, the purpose of this research is to suggest alternatives for strengthening the function of Free Trade Area of Gwangynag port. The main findings of this research is summarized as followings. First, a complex and total Free Trade Area through enhancing a production function is to be established. Second, for an efficient management & operation of Free Trade Area, a cooperative system establishment between Free Trade Areas and a single operation system is necessary.

Geometric Processing for Freeform Surfaces Based on High-Precision Torus Patch Approximation (토러스 패치 기반의 정밀 근사를 이용한 자유곡면의 기하학적 처리)

  • Park, Youngjin;Hong, Q Youn;Kim, Myung-Soo
    • Journal of the Korea Computer Graphics Society
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    • v.25 no.3
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    • pp.93-103
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    • 2019
  • We introduce a geometric processing method for freeform surfaces based on high-precision torus patch approximation, a new spatial data structure for efficient geometric operations on freeform surfaces. A torus patch fits the freeform surface with flexibility: it can handle not only positive and negative curvature but also a zero curvature. It is possible to precisely approximate the surface regardless of the convexity/concavity of the surface. Unlike the traditional method, a torus patch easily bounds the surface normal, and the offset of the torus becomes a torus again, thus helps the acceleration of various geometric operations. We have shown that the torus patch's approximation accuracy of the freeform surface is high by measuring the upper bound of the two-sided Hausdorff distance between the freeform surface and set of torus patches. Using the method, it can be easily processed to detect an intersection curve between two freeform surfaces and find the offset surface of the freeform surface.

The Illusion of Determinism and Free Will as a Functional Kinds Term (결정론의 환상과 기능류어로서의 자유의지)

  • Mo, Kiryong
    • Korean Journal of Cognitive Science
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    • v.24 no.3
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    • pp.237-270
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    • 2013
  • Determinism and compatibilism have thought that libertarianism contradicts the scientific view. This paper demonstrates that the hypothesis that free will exists does not cause any problems and contradictions, while maintaining pro-scientific view. Rather, determinism lacks scientific and demonstrative bases. At first, I reject dualistic self by assuming identity theory of the self and physical body & brain. Free will is a functional concept or property that can have multiple realization. Therefore we can recognize whether aliens or robots have free will through observation on their acts. 'Free will' is a functional kinds term like 'digestion'. As we know we have digestive function, we can know that we have free will even before knowing the necessity of its existence by understanding micro structure of human free will. The judgement that an individual has free will function depends on whether it has particular actions. Those actions are controlling and restraining actions in context, predicting future, making elaborate conditional sentences, etc. Real being of free will is the physical occupant of the function that makes those actions. Determinism is based on various kinds of misconceptions and misunderstandings. Determinists often confuse necessity of physical law and determinism. Another decisive misunderstanding is that free will postulates same conditions and different results from the same point of time. However, free will postulates that the two points of time are different. Because determinism is unnecessary redundant hypothesis influenced by religions, according to Ockham's Razor, determinism should be eliminated.

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The Effect of Intuitive Free Association and Systematic Free Association on the Creativity of High School Students Group in the Conceptual Design Process (직관적 및 체계적 자유연상기법이 개념설계과정에서 고등학생 집단의 창의성 향상에 미치는 효과)

  • Mheen, Se-Kee;Choi, Yu-Hyun
    • 대한공업교육학회지
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    • v.34 no.1
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    • pp.129-154
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    • 2009
  • The purpose of this study was to find the effect of intuitive free association and systematic free association on the creativity of high school students group in the conceptual design process. Based on this study result, the conclusion can be summarized as follows. 1. There was meaningful relation between intuitive free association and creativity factor of high school students. Mean value of experimental group A 's creativity and it's factor originality, practicality, elaboration, and fluency which treated intuitive free association was increased. 2. There was meaningful relation between systematic free association and creativity factor of high school students. Mean value of experimental group B 's creativity and it's sub factors: originality, problem solving, elaboration, and fluency which was treated systematic free association was increased. 3. It was found that two different divergent thinking does not show any meaningful difference in creativities of two groups. However, the meaningful difference was found in post creativity test in each groups sub-factors. There was meaningful difference in practicality factor, though there was no meaningful difference in originality, elaboration, fluency factors. Using the obtained results, it was concluded that intuitive thinking and systematic thinking play different roles in practicality which is one of sub-factors of the creativity of high school students. Consequently, it can be concluded that systematic thinking which leads students to take a step to solve a given problem can elicit more scientific thinking, and helps students create more practical solution in problem solving than intuitive thinking that emphasize the quantitative aspect of ideas.