• Kyungpook Mathematical Journal
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• v.60 no.1
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• pp.1-20
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• 2020

A simple but elegant result of Rival states that every sublattice L of a finite distributive lattice 𝒫 can be constructed from 𝒫 by removing a particular family 𝒥_L of its irreducible intervals. Applying this in the case that 𝒫 is a product of a finite set 𝒞 of chains, we get a one-to-one correspondence L ↦ 𝒟_𝒫(L) between the sublattices of 𝒫 and the preorders spanned by a canonical sublattice 𝒞^⋄ of 𝒫. We then show that L is a tight sublattice of the product of chains 𝒫 if and only if 𝒟_𝒫(L) is asymmetric. This yields a one-to-one correspondence between the tight sublattices of 𝒫 and the posets spanned by its poset J(𝒫) of non-zero join-irreducible elements. With this we recover and extend, among other classical results, the correspondence derived from results of Birkhoff and Dilworth, between the tight embeddings of a finite distributive lattice L into products of chains, and the chain decompositions of its poset J(L) of non-zero join-irreducible elements.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.3
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• pp.245-251
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• 2001

Nowadays, the first design elements of horizontal alignment are very important things to extension or improvement of highway. When the design elements ale lost or damaged, it is necessary to recalculation. In this paper, an investigation is made on the method of representation of horizontal alignment as a result of design element using generalization method. The results show that northing calculated about 0.2∼5 meters and easting calculated about 1∼40 meters between calculated and design data. Because the maximum value is a very small compared to total horizontal alignment length. calculated data have been fined to presentation of observed highway.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.2
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• pp.396-406
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• 2009

In extension to our previous study, we develop metadata that specify elements' structural orders, to increase the efficiency level of XML document's retrieval process. Then, we proposed a structure-based indexing model. We expect the model to generate a more efficient retrieval process of horizontally and vertically related elements. To evaluate the model's performance level, we developed an experimental prototype and conducted an experiment on an XML corpus. On average, descendant, ancestor and sibling retrievals were approximately twelve percent faster than the ETID model. And retrievals specifying structural orders of particular element types were approximately twenty-five percent faster than the ETID model. In conclusion, metadata, such as Etype, Asso and Lsso, may make a meaningful contribution to retrieval processes that specify elements' order.

• Computers and Concrete
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• v.17 no.1
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• pp.141-156
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• 2016

The search for new structural systems capable of associating performance and safety requires deeper knowledge regarding the mechanical behavior of structures subject to different loading conditions. The Strut-and-Tie Model is commonly used to structurally designing some reinforced concrete elements and for the regions where geometrical modifications and stress concentrations are observed, called "regions D". This method allows a better structural behavior representation for strength mechanisms in the concrete structures. Nonetheless, the topological model choice depends on the designer's experience regarding compatibility between internal flux of loads, geometry and boundary/initial conditions. Thus, there is some difficulty in its applications, once the model conception presents some uncertainty. In this context, the present work aims to apply the Strut-and-Tie Model to nonlinear structural elements together with a topological optimization method. The topological optimization method adopted considers the progressive stiffness reduction of finite elements with low stress values. The analyses performed could help the structural designer to better understand structural conceptions, guaranteeing the safety and the reliability in the solution of complex problems involving structural concrete.

• Computers and Concrete
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• v.21 no.5
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• pp.593-605
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• 2018

A nonlinear finite element modeling approach is developed to assess the behavior of a dowel bar embedded on a single concrete block substrate, subjected to monotonic loading. In this approach, a discrete representation of the steel reinforcing bar is considered, using beam finite elements with nonlinear material behavior. The bar is connected to the concrete embedment through nonlinear Winkler spring elements. This modeling approach can only be used if a new constitutive model is developed for the spring elements, to simulate the deformability and strength of the concrete substrate. To define this constitutive model, an extensive literature review was conducted, as well as 3 experimental tests, in order to select the experimental data which can be used in the calibration of the model. Based on this data, an empirical model was established to predict the global dowel response, for a wide range of bar diameters and concrete strengths. This empirical model provided the information needed for calibration of the nonlinear Winkler spring model, valid for dowel displacements up to 4 mm. This new constitutive model is composed by 5 stages, in order to reproduce the concrete substrate response.

• Journal of the Korean Society of Costume
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• v.20
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• pp.137-150
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• 1993

Sonia Delaunay was among the group of avant-garde artists drawn to Paris in the early part of this century who were exploring concepts of art that were felt to capture best the speed and me chanization of the modern world. She believed modernity-and her own attitude toward modern life-could be expressed through the primacy of color in art the dynamic inter-play of its dissonances and harmonies. The metap-hysical implications Delauny felt inherent in this idea made it applicable to all surfaces, and she was compelled to transform the world around her ac-cording to it. She set up a dialogue between fine art and everyday objects and accompplished the transition from representation work to her color theory through her investigation in embroidery and collage. This study is for Sonia Delaunay's field fo work which is close to fine and applied arts. To study Sonia Delaunay's work, I can find some points of her fashion designs. First, Simultaneous, which is to use collage tec-henics such as simultaneous and meterial to com-binate of variety meterial. Seound, Durability which is restoration of mor-dern fashion, Eventhough her work is 60 years old still it is foward to the furture. Imitation of textile which is devdloped by her, always looks new and fresh. Third, The elements of Folklore. Her elements of Russia, it appears on variety colors. Sepecially contemporary cloths has elements of folklore, we should use it and made it to suituble to contem-porary fashion of our country. For the furture, we need more study how to apply pictorial meterial of art into fashion design.

• Korean Journal of Computational Design and Engineering
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• v.12 no.3
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• pp.220-232
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• 2007

Current geometric modeling and analysis are commonly based on B-Rep modeling and a finite elements method respectively. Furthermore, it is difficult to represent an object whose material property is heterogeneous using the B-Rep method because the B-Rep is basically used for homogeneous models. In addition, meshes are required to analyze a property of a model when the finite elements method is applied. However, the process of generating meshes from B-Rep is cumbersome and sometimes difficult especially when the model is deformed as time goes by because the topology of deforming meshes are changed. To overcome those problems in modeling and analysis including homogeneous and heterogeneous materials, we suggest a unified modeling and analysis method based on implicit representation of the model using R-function which is suggested by Rvachev. For implicit modeling of an object a distance field is approximated and blended for a complex object. Using the implicit function mesh-free analysis is possible where meshes are not necessary. Generally mesh-free analysis requires heavy computational cost compared to a finite elements method. To improve the computing time of function evaluation, we utilize GPU programming. Finally, we give an example of a simple pipe design problem and show modeling and analysis process using our unified modeling and analysis method.

• Korean Institute of Interior Design Journal
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• no.27
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• pp.145-151
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• 2001

There is so much difference in the way we perceive nature whether from eastern or western, present or past standpoint. however, awareness of coexistence between human beings and nature along with the concept that the most natural is th e most beautiful remain unchanged. The desire to describe the beauty of nature have existed all through the ages, but the (new) naturalism movement was spawned in our time when so much devastation and side effects took place for the expediency of nature, and field of display has been trying new interpretation of nature with direct or applied method. Naturalism trend is studied using the categories such as relationship between human and nature, space concept in western and eastern society, and the definition of view of nature in modern time. Elements of naturalism display are classified into the element of physical properties and element beyond the physical properties, and then methodology on naturalism display is investigated, using the illustration of display examples, in order to know the most essential elements of display, which are the physical properties such as space, light, object, glass, are expressed based on the elemental concept like nature, an accident, dynamic state, variability. As mentioned above, Naturalism display consists of physical properties and phenomenon. How to ive strong impression to a spectator depends on the ability to create effective space applying these elements. The significance of this study comes to surface in a time when the tremendous emphasis is put on the importance of nature and concerns about the role of display has become even greater.

• Coupled systems mechanics
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• v.9 no.2
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• pp.125-145
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• 2020

In this paper, we present a 3D thermo-hydro-mechanical coupled discrete beam lattice model of structure built of the nonisothermal saturated poro-plastic medium subjected to mechanical loads and nonstationary heat transfer conditions. The proposed model is based on Voronoi cell representation of the domain with cohesive links represented as inelastic Timoshenko beam finite elements enhanced with additional kinematics in terms of embedded strong discontinuities in axial and both transverse directions. The enhanced Timoshenko beam finite element is capable of modeling crack formation in mode I, mode II and mode III. Mode I relates to crack opening, mode II relates to in-plane crack sliding, and mode III relates to the out-of-plane shear sliding. The pore fluid flow and heat flow in the proposed model are governed by Darcy's law and Fourier's law for heat conduction, respectively. The pore pressure field and temperature field are approximated with linear tetrahedral finite elements. By exploiting nodal point quadrature rule for numerical integration on tetrahedral finite elements and duality property between Voronoi diagram and Delaunay tetrahedralization, the numerical implementation of the coupling results with additional pore pressure and temperature degrees of freedom placed at each node of a Timoshenko beam finite element. The results of several numerical simulations are presented and discussed.

• East Asian mathematical journal
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• v.35 no.2
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• pp.115-139
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• 2019

In problem solving education, sentence problems are a tool for comprehensive evaluation of mathematical ability. The sentence problems refer to the problem expressed in sentence form rather than simply a numerical representation of mathematical problems. In order to solve sentence problems with a mixture of mathematical terms and general language, problem-solving ability including the ability to understand the meaning of sentences as well as the mathematical computation ability is required. Therefore, it is important to analyze syntactic elements from the linguistic aspects in sentence problems. The purpose of this study is to investigate the complexity of sentence problems in the length of sentences and the grammatical complexity of the sentences in the depth of the sentences by analyzing the 51 sentence problems presented in the $4^{th}$ grade mathematics textbook(2015 revised curriculum). As a result, it was confirmed that it is necessary to examine the length and depth of the sentence more carefully in the teaching and learning of sentence problems. Especially in elementary mathematics, the sentence problems requires a linguistic understanding of the sentence, and therefore it is necessary to consider syntactic elements in the process of developing and teaching sentence problems in mathematics textbook.