• 한국초등수학교육학회지
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• 제23권1호
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• pp.43-57
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• 2019

초등학교 1학년 수학에서 '아무것도 없음'을 나타내는 수 0은 '1보다 1작은 수'의 의미로 도입된다. 또한 1, 2학년 수학에서 처음 제시되는 0의 성질은 0을 더하고, 빼고, 곱하는 예시적인 상황으로 설명된다. 그러나 이후 학습에서는 0의 의미와 성질을 더 이상 명시적으로 다루지 않는다. 본 연구에서는 초등학교 학생들이 0의 의미와 성질을 이해하는 데 도움을 주기 위하여 초등학교 수학 교과서에 제시된 0의 도입 방식과 계산식을 해결하는 과정에서의 0의 성질의 적용 방안에 대하여 논의하고자 한다. 이를 통해 초등학교 수학에서 0의 의미와 성질에 관한 교육적 시사점을 도출하고자 한다.

• 대한수학회논문집
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• 제19권2호
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• pp.329-336
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• 2004

In this paper, we study relationships between zero characteristic properties and minimality of orbit closures or limit sets of points. Also, we characterize the set of points of zero characteristic properties. We show that the set of points of positive zero characteristic property in a compact spaces X is the intersection of negatively invariant open subsets of X.

• 대한수학회지
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• 제46권2호
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• pp.313-325
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• 2009

We consider zero-divisor graphs with respect to primal, nonprimal, weakly prime and weakly primal ideals of a commutative ring R with non-zero identity. We investigate the interplay between the ringtheoretic properties of R and the graph-theoretic properties of ${\Gamma}_I(R)$ for some ideal I of R. Also we show that the zero-divisor graph with respect to primal ideals commutes by localization.

• 복식
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• 제66권4호
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• pp.61-76
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• 2016

The importance of environment has come into focus recently, and this has led to increased attention on zero waste fashion design as a method to minimize waste from the production stage of fashion goods. The purpose of this study was to analyze the development method types and the characteristics of zero waste fashion design in order to study the eco-friendly meanings of zero waste fashion design, as well as its meaning as creative design development methods. Through the case analysis of recent designs, the design types of zero waste fashion design were largely classified into cut and sew, folding, draping, and non-woven types, and they were classified again according to the characteristics of production process. According to the result of analyzing fashion design development methods of zero waste fashion designs based on the process of completing design, they were classified into pattern making, computer programming, draping, assembling of the unit, and non-woven moulding methods, and the aspect of combined use rather than utilization of one method appeared. Formative characteristics of zero waste fashion design included decorative beauty, formative beauty, and transformable beauty and its design characteristics were fortuity and unexpected properties, breaking stereotypes, structural flexibility and futuristic innovation.

• 대한수학회지
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• 제56권5호
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• pp.1403-1418
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• 2019

Let R be a commutative ring with unity. If f(x) is a zero-divisor polynomial such that $f(x)=c_f f_1(x)$ with $c_f{\in}R$ and $f_1(x)$ is not zero-divisor, then $c_f$ is called an annihilating content for f(x). In this case $Ann(f)=Ann(c_f )$. We defined EM-rings to be rings with every zero-divisor polynomial having annihilating content. We showed that the class of EM-rings includes integral domains, principal ideal rings, and PP-rings, while it is included in Armendariz rings, and rings having a.c. condition. Some properties of EM-rings are studied and the zero-divisor graphs ${\Gamma}(R)$ and ${\Gamma}(R[x])$ are related if R was an EM-ring. Some properties of annihilating contents for polynomials are extended to formal power series rings.

• 한국전기전자재료학회논문지
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• 제23권2호
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• pp.137-142
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• 2010

A plane wave expansion method (PWEM) was applied for photonic band structure calculation. We examined zero group velocity modes in photonic crystal. The zero group velocity modes were obtained at the second band along F-K direction. We expanded higher order Brillouin zone (BZ) to find the locations of zero group velocity modes and to investicate their properties. We found twelve locations, inside the first Brillouin zone, where the group velocities became zero. Also, we calculated band structure and group velocity in off-plane configuration.

• Kyungpook Mathematical Journal
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• 제54권2호
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• pp.197-201
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• 2014

In this paper, we study some properties of finite or infinite poset P determined by properties of the ideal based zero-divisor graph properties $G_J(P)$, for an ideal J of P.

• Communications for Statistical Applications and Methods
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• 제7권3호
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• pp.959-966
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• 2000

A dimensionality assessment procedure DETECT uses the property of being near zero of conditional covariances as an indication of unidimensionality .This study provides the convergent properties to zero of conditional covariances when the dta is unidimensional, with which DETECT extends its theoretical grounds.

• 대한기계학회논문집
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• 제18권3호
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• pp.670-680
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• 1994

The thermophysical properties of Non-Newtonian fluid as the function of the temperature and the concentration are needed in many rheological heat transfer and fluid mechanics problems. The present work investigated the effects of the concentration and the temperature on the thermophysical properties of purely-viscous Non-Newtonian fluids such as the isobaric thermal expansion coefficient, density, zero-shear-rate viscosity, and zero-shear-rate dynamic viscosity within the experimental temperature range from $25^{\circ}C$ to $55^{\circ}C$. The densities of the test fluids were determined as the function of the temperature by utilizing a reference density and the least square equation for the measured isobaric thermal expansion coefficient. As the concentration of purely-viscous Non-Newtonian fluid was increased up to 10,000 wppm, the densities were proportionally increased up to 0.4%. The zero-shear-rate viscosities of test fluids were measured before and after the measurements of the first thermal expansion coefficients and the densities of Non-Newtonian fluid. Even though they were changed up to approximately 22% due to thermal aging and cycling, they had no effects on the thermal expansion coefficients and the densities of Non-Newtonian fluid. The zero-shear-rate dynamic viscosities for purely-viscous Non-Newtonian fluids were compared with the values for distilled water. They showed the similar trend with the zero-shear-rate viscosities due to small differences in the densities for both distilled water and purely-viscous Non-Newtonian fluid.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제10권1호
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• pp.25-35
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• 2003

We study equivalent definitions and some categorical properties of completely regular quasi-ordered spaces and zero-dimensional quasi-ordered spaces. Using the o-completely regular (resp. o-zero-dimensional) filters on a completely regular (resp. zero-dimensional) quasi-ordered space, we show that the category COMPOS (resp. ZCOMPOS) of compact (resp. compact zero-dimensional) partially ordered spaces is reflective in the category CRQOS (resp. ZQOS) of completely regular (resp. zero-dimensional) quasi-ordered spaces and continuous isotones.