• International Journal of Precision Engineering and Manufacturing
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• v.7 no.2
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• pp.25-29
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• 2006

Analysis of structures which are composed of numerous repeated unit structures can be simplified by using homogenized properties. If the unit structure is repeated in one direction, the whole structure may be regarded as a beam. Once the effective stiffness is obtained from the analysis of the unit structure in a proper way, the effort for the detail modeling of the global structure is not required, and the real structure can be replaced simply with a beam. This study proposes a kinematical periodicity constraint to be imposed on the FE model of the unit structure, which improves the accuracy of the effective stiffness. The method is employed to a one dimensionally arrayed 3D structure containing periodically repeated unsymmetrical holes. It is demonstrated that the deformation behavior of the homogenized beam agrees well with that of the real structure.

• KIPS Transactions on Software and Data Engineering
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• v.10 no.6
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• pp.243-250
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• 2021

With the increased development of 3D VR applications augmented by recent VR/AR/MR technologies and by the advance of 3D devices, interchangeability and portability of 3D data have become essential. 3D files should be processed in a standard data format for common usage between applications. Providing standardized libraries and data structures along with the standard file format means that a more efficient system organization is possible and unnecessary processing due to the usage of different file formats and data structures depending on the applications can be omitted. In order to provide the function of using a common data file and data structure, this research is intended to provide a programming binding tool for generating and storing standardized data so that various services can be developed by accessing the common 3D files. To achieve this, this paper defines a common data structure including classes and functions to access X3D files with a standardized scheme using the Python programming language. It describes the implementation of a Python language binding viewer, which is an X3D VR viewer for rendering standard X3D data files based on the language binding interface. The VR viewer includes Python based 3D scene libraries and a data structure for creation, modification, exchange, and transfer of X3D objects. In addition, the viewer displays X3D objects and processes events using the libraries and data structure.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.8
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• pp.3950-3964
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• 2017

With the increasing popularity of 3D technology such as 3D printing, 3D modeling, etc., there is a growing need to search for similar models on the internet. Matching non-rigid shapes has become an active research field in computer graphics. In this paper, we present an efficient and effective non-rigid model retrieval method based on topological structure and local volume. The integral geodesic distances are first calculated for each vertex on a mesh to construct the topological structure. Next, each node on the topological structure is assigned a local volume that is calculated using the shape diameter function (SDF). Finally, we utilize the Hungarian algorithm to measure similarity between two non-rigid models. Experimental results on the latest benchmark (SHREC' 15 Non-rigid 3D Shape Retrieval) demonstrate that our method works well compared to the state-of-the-art.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.6
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• pp.1399-1406
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• 2009

Proteins are one of essential part of organisms; many proteins are enzymes that catalyze biochemical reactions and are vital to metabolism. Researching for 3D structure of proteins is important because functions of proteins are determined by 3D structure of them. In this study, we developed graphic tool that supports comparison and observation of the two proteins' 3D structure in the single screen. It also supports some comparison data to help researcher's easy comparison and observation works.

• Journal of Korea Multimedia Society
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• v.15 no.10
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• pp.1257-1263
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• 2012

An implementation of animation module using the 3D body data scanned by laser scanner is reported in this paper. Characteristic points of the skeleton in human body were picked up as pivot point for 3D rotation. The body data set wes reconstructed as objects built in hierarchical tree structure, which is based on skeleton model. In order to implement the 3D animation of the laser scanned body data, the vertexes of the objects were connected as skeleton structure and animated to follow dynamic patterns inputted by user.

• Journal of the Chungcheong Mathematical Society
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• v.24 no.3
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• pp.503-515
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• 2011

Let G be a compact connected semisimple Lie group, B the Killing form of the algebra g of G, and g the invariant metric induced by B. Then, we obtain a necessary and sufficient condition for a left invariant linear connection D with a Weyl structure ($D,\;g,\;{\omega}$) on (G, g) to be projectively flat (resp. Einstein-Weyl). And, we also get that if a left invariant linear connection D with a Weyl structure ($D,\;g,\;{\omega}$) on (G, g) which has symmetric Ricci tensor $Ric^D$ is projectively flat, then the connection D is Einstein-Weyl; but the converse is not true. Moreover, we show that if a left invariant connection D with Weyl structure ($D,\;g,\;{\omega}$) on (G, g) is projectively flat (resp. Einstein-Weyl), then D is a Yang-Mills connection.

• Journal of IKEEE
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• v.25 no.4
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• pp.778-781
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• 2021

In this paper, we propose the 16-layer 3D NAND Flash memory compact modeling using SPICE. In the same structure and simulation conditions, the channel potential about Down Coupling Phenomenon(DCP) and Natural Local Self Boosting (NLSB) were simulated and analyzed with Technology Computer Aided Design(TCAD) tool Atlas(Silvaco^TM) and SPICE, respectively. As a result, it was confirmed that the channel potential of TCAD and SPICE for the two phenomena were almost same. The SPICE can be checked the device structure intuitively by using netlist. Also, its simulation time is shorter than TCAD. Therefore, using SPICE can be expected to efficient research on 3D NAND Flash memory.

• Journal of Microbiology and Biotechnology
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• v.3 no.1
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• pp.51-56
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• 1993

The structure of herbicidal compound, 3D5, isolated from the culture broth of Streptomyces sp. 3D5, was elucidated as a 16-membered diene macrolide by the spectroscopic method. It was identical with bafilomycin D which has been known to be an insecticidal compound and an inhibitor of $K^{+}-dependent$ ATPase. However, this is the first report which shows that bafilomycin D has a herbicidal activity.

• Journal of the Korea Furniture Society
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• v.26 no.4
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• pp.383-391
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• 2015

In recent years the industry has utilized some of the 3D printers in the manufacturing process a trend which spread also a personal desktop 3D printer priced. The 3D printer can create the 3D object by using an ink or a laser instead of the powders, and various liquid plastic material. Properties of 3D printers are liquid, solid, powder and raw materials are also classified as varied. New ideas and processes in the form of designer furniture, becoming increasingly evolved through the development of materials and technologies. Science, art and technology combine to create a new aesthetic for the complex and free binding structure is a combination of design and materials are available in craft and the structure appears not showing. 3D scanning was not simply continue to develop as the production process by a variety of tools and content transformation. Create new mathematical tables and chairs designed by the theory fit the digital age shows a coupling structure with decoration into small pieces. It has created a new craft technique in the digital age.

• Journal of Korea Game Society
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• v.14 no.6
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• pp.29-38
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• 2014

In the large scale indoor 3D game scenes, the data amount of potentially visible set (PVS) which pre-computes the information of occlusion culling can be huge. However, the large part of them can be represented as zero. In this paper, the effective hardware structure is designed, which compresses PVS data as the way of zero run length encoding (ZRLE) during building the scene trees of 3D games in mobile environments. The compression ratio of the proposed structure and the rendering speed (frame per second: FPS) according to both PVS culling and frustum culling are analyzed under 3D game simulations.