• 한국정밀공학회지
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• 제20권7호
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• pp.208-216
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• 2003

In this paper, a two-dimensional electroelastic analysis is performed on a piezoelectric material with an open crack. The approach of Lekhnitskii's complex potential functions is used in the derivation and Bueckner's weight function theory is extended to piezoelectric materials. The stress intensity factors and the electric displacement intensity factor are calculated by the weight function theory.

• Fibers and Polymers
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• 제5권2호
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• pp.139-144
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• 2004

The orthotropic theory is applied for the nonwoven fabrics that have a preferred orientation direction, the case if the structure is not isotropic. The polynomial regression analysis is employed to allow the attainment of more statistically meaningful information. A functional form based on the transformation rule is developed for the orthotropic approach. The predictions thus obtained are seen to be in excellent agreements with experimental data and the resulting compliances exhibit meaningful relationships for the processing conditions. The compatibility of the compliances from tensile and shear analyses has been explored prior to a practical application of the four compliances defining the in-plane strain-stress field.

• 한국언어정보학회지:언어와정보
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• 제14권1호
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• pp.197-227
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• 2010

This study reviews (i) the (dis)advantages of two major semantic theories of focus, i.e., the Alternative Semantics (AS) and the Structured Meaning Theory (SM), and (ii) the hybrid analysis consisting of these two theories proposed by Krifka (2006). After pointing out a problem of this hibrid analysis, this study attempts to show the third alternative, i.e., the theory of identificational predication for focus can solve this problem.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제9권3호
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• pp.233-241
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• 2005

Mathematics has developed dramatically in today's world and come to be increasingly put into practical use in various fields in society. However, many Japanese students dislike mathematics. We have to study mathematics education with this situation in our mind. When we consider a better educational material, we don't have to consider only within the framework of the current school mathematics. We can expect to find good mathematical materials in fields beyond the school mathematics. In this paper, we study how the inclusion of idea such as 'fuzzy theory' and 'graph theory' influences pupils' approaches to learning mathematics.

• 산업기술연구
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• 제10권
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• pp.3-8
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• 1990

This paper presents a linear state feedback control approach to the stabilization of discrete-time uncertain systems with bounded uncertain parameters. The approach is based on the LQ(linear quadratic) regulator theory and Lyapunov's stability analysis. Asymptotically stable behavior is guaranteed in the presence of parameter uncertainties, and the upper bound of the performance index is determined.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.379-379
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• 1998

The report presents an approach to constructing or control algorithms for finite dimensional dynamical systems under the deficit of information about dynamical disturbances. The approach is based on the constructions of the extremal shift strategy of the differential game theory.

• 한국콘텐츠학회논문지
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• 제14권4호
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• pp.456-466
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• 2014

본 연구는 종교를 문화-언어로 이해한 린드벡의 후기자유주의에 관한 것이다. 전통적인 기독교 신학의 인식-명제적 접근과 자유주의의 경험-표현주의적 접근이 포스트모던적 종교 현상에 대한 해결책이 되지 못함을 인식한 조지 린드벡은 기존의 두 접근법들을 극복할 대안으로서 문화-언어적 접근법을 제시한다. 린드벡의 후기자유주의가 가진 첫 번째 통찰은 종교를 문화나 언어로 이해한다는 것인데, 이는 인간이 언어를 배우듯 종교에도 익숙해진다는 이유에서다. 두 번째 통찰은 첫 번째 것에서 파생된 것으로서 교리를 문법으로 이해하는 것이다. 만약 종교와 교리를 이런 식으로 이해한다면 종교 간의 갈등과 충돌의 문제는 자연스럽게 해결될 것인데, 이는 각각의 종교가 마치 언어에 좋고 나쁨이나 옳고 그름이 없는 것처럼 나름대로의 체계 안에서 해석될 수 있기 때문이다. 이 접근법이 종교 상호간에 화해를 가능케 하고, 실행성을 강조하고, 또 성경을 귄위 있는 신학적 텍스트로 삼았다는 점은 중요한 기여로 꼽을 수 있다. 하지만 이것은 텍스트 자체보다는 교회의 해석에 더 큰 비중을 두었고, 진리를 내적 일관성으로 격하시켰고, 모든 종교를 동일한 가치로 보는 극단적 상대주의와 언어가 종교생활에 필수적이라는 엘리트주의를 조장했을 뿐 아니라 신학적 종말론을 주장함으로써 명제주의로 회귀했다는 문제점을 안고 있다. 그러므로 연구자는 린드벡의 문화-언어의 종교이론을 신학적 보수주의와 자유주의의 한계를 극복할 대안으로는 부족하다고 결론 내린다.

• Earthquakes and Structures
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• 제1권1호
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• pp.1-19
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• 2010

It has been known that one-dimensional rod theory is very effective as a simplified analytical approach to large scale or complicated structures such as high-rise buildings, in preliminary design stages. It replaces an original structure by a one-dimensional rod which has an equivalent stiffness in terms of global properties. If the structure is composed of distinct constituents of different stiffness such as coupled walls with opening, structural behavior is significantly governed by the local variation of stiffness. This paper proposes an extended version of the rod theory which accounts for the two-dimensional local variation of structural stiffness; viz, variation in the transverse direction as well as longitudinal stiffness distribution. The governing equation for the two-dimensional rod theory is formulated from Hamilton's principle by making use of a displacement function which satisfies continuity conditions across the boundary between the distinct structural components in the transverse direction. Validity of the proposed theory is confirmed by comparison with numerical results of computational tools in the cases of static, free vibration and forced vibration problems for various structures.

• Structural Engineering and Mechanics
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• 제45권3호
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• pp.355-371
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• 2013

Single- and multi-span orthotropic functionally graded hollow cylinders subjected to axisymmetrical bending are investigated on the basis of a unified shear deformable shell theory, in which the transverse displacement is expressed by means of a general shape function. To approach the through-thickness inhomogeneity of the hollow cylinder, a laminated model is employed. The shape function therefore shall be determined for each fictitious layer. To improve the computational efficiency, we resort to a transfer matrix method. Based on the principle of minimum potential energy, equilibrium equations are established, which are then solved analytically using the transfer matrix method for arbitrary boundary conditions. Numerical comparisons among a third-order shear deformable shell theory, an exact elastic theory and the present theory are provided for a simply supported hollow cylinder, from which the present theory turns out to be superior in stress estimation. Distributions of displacements and stresses in single- and three-span hollow cylinders with different boundary conditions are also illustrated in numerical examples.

• 수산경영론집
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• 제23권2호
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• pp.53-67
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• 1992

It has been recognized, virtually from the time of its inception, that fisheries economics, like other aspects of resource economics, should ideally be cast in capital-theoretic terms. The fish population or biomass can be viewed as a capital stock in that, like conventional or man-made capital, it is capable of yielding a sustainable consumption flow through time. This study is to introduce the optimal control theory which was extended from the theory of calculus of variations into the study of former static theory of fisheries economics started by Gordon (1954). The optimal control theory eliminated the inadequacies of the classical techniques to a large extent. From this point of view, this study, on the base of Schaefer model, summerizes most of major results achieved so far, but does so in a manner such that the links with capital theory are made transparent. This study explores two sets of problems. The first concerns the optimal approach to the equilibrium stock, i.e. the optimal investment policy. The second set of problems arises from the relaxation of the highly restrictive assumption of autonomy (i.e. the assumption that the parameters are independent of time), then concludes the relaxation of linearity assumption together with the complexities caused by that.