• 제목/요약/키워드: elements

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WEAKLY CANCELLATIVE ELEMENTS IN SEMIGROUPS

  • Shin, Jong-Moon
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제17권1호
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    • pp.81-86
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    • 2010
  • This paper gives some sorts of weakly cancellative of elements which are to be or not to be left magnifying elements in certain semigroups and gives a semilattice congruence in a weakly separative semigroup.

3차원 판구조물 해석을 위한 삼각형요소와 사각형 요소의 비교에 관한 연구 (A Study on the Comparison of Triangular and Quadrilateral Elements for the Analysis of 3 Dimensional Plate Structures)

  • 왕지석;김유해;이우수
    • Journal of Advanced Marine Engineering and Technology
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    • 제26권3호
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    • pp.344-352
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    • 2002
  • In the analysis of the 3 dimensional plate structures by the finite element method, the triangular elements are generally used for the global stiffness matrix of the analyzed system. But the triangular elements of the plates have some problems in the process of formulation and in the precision of analysis. The formulation of the finite element method to analyze 3 dimensional plate structures using quadrilateral elements is presented in this paper. The degree of freedom off nodal point is 6, that is, the displacements in the direction off-y-z is and the rotations about x-y-z axis and then the degree of freedom off element is 24. For the comparison of the analysis using triangular elements and quadrilateral elements, the rectangular plates subjected to the uniform load and a concentrated load on the centroid of the plate, for which the theoretical solutions have been obtained, are analyzed. The calculated deflections of the rectangular plates using the finite element method by the triangular elements and the quadrilateral elements are also compared with the deflections of the plates calculated by theoretical solutions. The defections of the rectangular plates calculated by the finite element method using the quadrilateral elements are closer to the theoretical solutions than the defections calculated by the finite element method using the triangular elements. The deflection of the centroid of plate, calculated by the finite element method, converges to that of theoretical solution as the number of elements is increased. This convergence is much more rapid for the case of using the quakrilateral elements than fir the case of using triangular elements.

조망 경관에 대한 아파트 거주자들의 인지 특성 (The Tendencies in Apartment Inhabitants' Recognition of Landscape Elements)

  • 이상복;문지원;하재명
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2006년도 추계학술발표대회 논문집
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    • pp.248-252
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    • 2006
  • This study is intended to understand the intrinsic attributes of the view from the apartment unit in consideration of the diverse and complex elements of the view. To this end, the Questionnaire survey was conducted to identify the tendency in the recognition by apartment dwellers. The Questionnaire survey was conducted for the apartment residents to identify their interest in and the general trend in their recognition of the view from the living rooms of their housing unit, where Questionnaire items regarding landscape elements, the distances to and location of the landscape elements, and floor locations were compiled on the basis of the results from the field survey in the previous study. Consequently, the following results have been derived. 1) Apartment residents recognize not only natural landscape elements but also artificial elements, and prefer natural elements to artificial ones. 2) It is also indicated that they recognize the distances to and locations of landscape elements and that the satisfaction for the distance and location varies depending on the type of the landscape elements. 3) Furthermore, the floor of each unit is shown to result in certain differences in the recognized landscape elements. The cross-analysis between the floor and satisfaction indicates that the higher the floor, the more satisfied the residents are with the view.

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사각형 판 유한 요소들의 정적 성능 비교 분석 I (Comparative Study on the Performance of Quadrilateral Plate Elements for the static Analysis of Limear Elastic structures( I );Displacements)

  • 이병채;이용주
    • 전산구조공학
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    • 제3권4호
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    • pp.91-104
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    • 1990
  • 사각형 판 유한요소의 정적 성능을 여러 가지 문제에 대한 수치 실험을 통해 비교 분석하였다. Kirchhoff이론과 Mindlin이론에 근거한 변위요소, 평형요소, Mixed 또는 Hybrid요소들을 대상으로 문헌조사를 통해 우수요소를 선정하였으며 사각형 판 문제, 마름모형 판 문제, 원형 판 문제, 외팔보형 판 문제를 다양한 격자, 경계조건에 대해 풀어 해를 비교하였다. Kirchhoff요소에서는 12자유도요소로 Armanios의 요소, 24 자유도 요소로 Watkins요소의 거동이 우수하였으나 전반적으로 Mindlin요소에 비해 거동이 떨어진다. Mindlin요소 중에서는 Hinton의 요소가 효율성, 수렴성, 신뢰성의 면에서 가장 우수하나 마름모형 판 문제나 뒤틀린 격자 문제등에서는 거동이 좋지 않으므로 계속 연구할 필요가 있다.

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최근 20년간 디자인 평가항목 변천에 관한 연구 - 독일설계경기를 중심으로 - (A Study on the Change of Critical Elements of the Design Evaluation during the last two Decades - Focused on Architectural Competition in Germany -)

  • 조자연
    • 한국실내디자인학회논문집
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    • 제20권2호
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    • pp.3-9
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    • 2011
  • In this study, the change of critical elements of the design evaluation was investigated during two decades at the architectural competition which was held nationwide in Germany. Specifically, the periods of investigation span both from July 1989 to June 1990 and from July 2009 to June 2010. The results of the analysis show that the cost of construction, the maintenance cost, the design of facade and the energy conservation are being magnified for the new important elements. The images of buildings and the economic aspects are meant to be high. The frequency of the critical elements for interior spaces is approximately two times more important than those for the forms and outdoor spaces. Overall, many juries of the architectural competition in Germany were interested in the elements for interior spaces. The field of function accounts for roughly the half of four basic architectural fields such as function, others, aesthetic and construction fields. The critical elements are required persistently such as context, Circulation, organization of space, form, landscape and outdoor space design, arrangement of building, cost of construction, function, design of facade, location of main entrance. These items are regarded as the most important elements of the design evaluation at the competition. Knowing the change of critical elements of the design evaluation, we can understand the trend of architecture in Germany. The results of this study can be applied in Korea to develop the critical elements of design.

Identification and Phylogeny of the Human Endogenous Retrovirus HERV-W LTR Family in Human Brain cDNA Library and Xq21.3 Region

  • KIM, HEUI-SOO;TIMOTHY J. CRO
    • Journal of Microbiology and Biotechnology
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    • 제12권3호
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    • pp.508-513
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    • 2002
  • Human endogenous retroviral long terminal repeats (LTRs) have been found to be coexpressed with sequences of genes located nearby. It has been suggested that the LTR elements have contributed to the structural change or genetic variation of human genome connected to various diseases. The HERV-W family has been identified in the cerebrospinal fluids and brains of individuals with schizophrenia. Using a cDNA library derived from a human brain, the HERV-W LTR elements were examined and five new LTR elements were identified. These elements were examined using a YAC clone panel from the Xq21.3 region linked to psychosis that was replicated on the Y chromosome after the separation of the chimpanzee and human lineages. Fourteen elements of the HERV-W LTR were identified in that region. Those LTR elements showed a high degree of sequence similarity ($91.8-99.5\%$) with previously reported HERV-W LTR. A phylogenetic tree obtained from the neighbor-joining method revealed that new HERV-W LTR elements were closely related to the AXt000960, AF072504, and AF072506 from the GenBank database. The data indicates that several copy numbers of the HERV-W LTR elements exist on the Xq21.3 region and are also expressed in the human brain. These LTR elements need to be further investigated as potential leads to neuropsychiatric diseases.

반무한 다중 구조계의 비선형 유한요소 - 경계요소 해석 (Analysis of Multi-Layered Structural Systems Using Nonlinear Finite Elements-Boundary Elements)

  • 김문겸;장정범;이상도;황학주
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1992년도 봄 학술발표회 논문집
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    • pp.58-64
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    • 1992
  • It is usual that underground structures are constructed within multi-layered medium. In this paper, an efficient numerical model ling of multi-layered structural systems is studied using coupled analysis of finite elements and boundary elements. The finite elements are applied to the area in which the material nonlinearity is dominated, and the boundary elements are applied to the far field area where the nonlinearity is relatively weak. In the boundary element model 1 ins of the multi-layered medium, fundamental solutions are restricted. Thus, methods which can utilize existing Kelvin and Melan solution are sought for the interior multi-layered domain problem and semi infinite domain problem. Interior domain problem which has piecewise homogeneous layers is analyzed using boundary elements with Kelvin solution; by discretizing each homogeneous subregion and applying compatibility and equilibrium conditions between interfaces. Semi-infinite domain problem is analyzed using boundary elements with Melan solution, by superposing unit stiffness matrices which are obtained for each layer by enemy method. Each methodology is verified by comparing its results which the results from the finite element analysis and it is concluded that coupled analysis using boundary elements and finite elements can be reasonable and efficient if the superposition technique is applied for the multi-layered semi-infinite domain problems.

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제화의 고객지향적 품질창조에 관한 실증적 연구 - Kano의 모형과 QFD를 중심으로 (An Empirical Study on Customer-Oriented Quality Creation of Shoe : Focusing on Kano′s Model and QFD)

  • 김희탁;이종철
    • 품질경영학회지
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    • 제30권1호
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    • pp.1-21
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    • 2002
  • The purpose of this study was to empirically examine the customer oriented quality creation by considering quality elements required by customers in the product design process. The study tried to extract attractive quality elements by using Kano's model. After identifying the elements HOQ(the house of quality) of QFD(quality function deployment) was used to identify the trend of quality elements evaluation. Test for equal means (t-test) was applied to verify the attractive quality elements of adult shoes. It made us find the customer oriented quality elements from the customer needs and latent dissatisfaction. We collected the opinions of experts on shoes and complete the cause and effect diagram and affinity diagram (KJ method). The data of the questionnaire was put to the QFD and the contents of quality elements was identified by brain storming method. We calculated indexes which were the multiplication of weight and marks of quality elements in the cross table of the HOQ by QFD. Then we tested for the equality of means between the indexes and the sum of attractive quality elements. The results for equal means were statistically significant. To create the customer quality the product design should be differentiated between the age groups over attractive quality elements.

Euclid 원론과 Pardies 원론의 비교 연구 (A Comparative Study on Euclid's Elements and Pardies' Elements)

  • 장혜원
    • 한국수학사학회지
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    • 제33권1호
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    • pp.33-53
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    • 2020
  • Euclid's Elements has been considered as the stereotype of logical and deductive approach to mathematics in the history of mathematics. Nonetheless, it has been criticized by its dryness and difficulties for learning. It is worthwhile to noticing mathematicians' struggle for providing some alternatives to Euclid's Elements. One of these alternatives was written by a French scientist, Pardies who called it 'Elemens de Geometrie ou par une methode courte & aisee l'on peut apprendre ce qu'il faut scavoir d'Euclide, d'Archimede, d'Apllonius & les plus belles inventions des anciens & des nouveaux Geometres.' A precedent research presented its historical meaning in traditional mathematics of China and Joseon as well as its didactical meaning in mathematics education with the overview of this book. However, it has a limitation that there isn't elaborate comparison between Euclid's and Pardies'in the aspects of contents as well as the approaching method. This evokes the curiosity enough to encourage this research. So, this research aims to compare Pardies' Elements and Euclid's Elements. Which propositions Pardies selected from Euclid's Elements? How were they restructured in Pardies' Elements? Responding these questions, the researcher confirmed his easy method of learning geometry intended by Pardies.

Analytical p-version finite elements and application in analyses of structural collision protection

  • Zhu, B.;Chen, Y.M.;Leung, A.Y.T.
    • Structural Engineering and Mechanics
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    • 제23권5호
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    • pp.487-504
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    • 2006
  • Several new versatile two-dimensional p-version finite elements are developed. The element matrices are integrated analytically to guarantee the accuracy and monotonic convergence of the predicted solutions of the proposed p-version elements. The analysis results show that the convergence rate of the present elements is very fast with respect to the number of additional Fourier or polynomial terms in shape functions, and their solutions are much more accurate than those of the linear finite elements for the same number of degrees of freedom. Additionally, the new p-version plate elements without the reduced integration can overcome the shear locking problem over the conventional h-version elements. Using the proposed p-version elements with fast convergent characteristic, the elasto-plastic impact of the structure attached with the absorber is simulated. Good agreement between the simulated and experimental results verifies the present p-version finite elements for the analyses of structural dynamic responses and the structural elasto-plastic impact. Further, using the elasto-plastic impact model and the p-version finite element method, the absorber of the T structure on the Qiantang River is designed for its collision protection.