• Title/Summary/Keyword: 3-Dimensional Structure

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Phantom Protection Method for Multi-dimensional Index Structures

  • Lee, Seok-Jae;Song, Seok-Il;Yoo, Jae-Soo
    • International Journal of Contents
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    • v.3 no.2
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    • pp.6-17
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    • 2007
  • Emerging modem database applications require multi-dimensional index structures to provide high performance for data retrieval. In order for a multi-dimensional index structure to be integrated into a commercial database system, efficient techniques that provide transactional access to data through this index structure are necessary. The techniques must support all degrees of isolation offered by the database system. Especially degree 3 isolation, called "no phantom read," protects search ranges from concurrent insertions and the rollbacks of deletions. In this paper, we propose a new phantom protection method for multi-dimensional index structures that uses a multi-level grid technique. The proposed mechanism is independent of the type of the multi-dimensional index structure, i.e., it can be applied to all types of index structures such as tree-based, file-based, and hash-based index structures. In addition, it has a low development cost and achieves high concurrency with a low lock overhead. It is shown through various experiments that the proposed method outperforms existing phantom protection methods for multi-dimensional index structures.

A Two-Dimensional Terrace-Like N-heterocyclic-Pb(II) Coordination Compound: Structure and Photoluminescence Property

  • Ma, Kui-Rong;Zhu, Yu-Lan;Zhang, Yu;Li, Rong-Qing;Cao, Li
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.894-898
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    • 2011
  • The first example of lead compound from $Pb(NO_3)_2$ and $H_3L$ N-heterocyclic ligand $(H_3L\;=\;(HO_2C)_2(C_3N_2)(C_3H_7)CH_2(C_6H_4)(C_6H_3)CO_2H)$, $[Pb_4(L')_4]{\cdot}5H_2O$ 1 (L' = OOC$(C_3H_7)(C_3N_2)CH_2(C_6H_4)(C_6H_3)COO)$, has been obtained under hydrothermal condition by decarboxylation, and characterized by elemental analysis, IR, TGDTA, and single-crystal X-ray diffraction. Compound 1 possesses a rare two-dimensional upper-lower offset terrace-like layer structure. In 1, crystallographic distinct Pb(II) ion adopts five-coordination geometry, and two lattice water molecules occupy the voids between 2-D layers. Results of solid state fluorescence measurement indicate that the emission band 458 nm may be assigned to $\pi^*-n$ and $\pi^*-\pi$ electronic transitions within the aromatic systems of the ligand L', however, the emission bands centred at 555 nm, 600 nm and 719 nm may be derived from phosphorescent emission ($\lambda_{excitation}$ = 390 nm).

Programming Characteristics on Three-Dimensional NAND Flash Structure Using Edge Fringing Field Effect

  • Yang, Hyung Jun;Song, Yun-Heub
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.5
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    • pp.537-542
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    • 2014
  • The three-dimensional (3-D) NAND flash structure with fully charge storage using edge fringing field effect is presented, and its programming characteristic is evaluated. We successfully confirmed that this structure using fringing field effect provides good program characteristics showing sufficient threshold voltage ($V_T$) margin by technology computer-aided design (TCAD) simulation. From the simulation results, we expect that program speed characteristics of proposed structure have competitive compared to other 3D NAND flash structure. Moreover, it is estimated that this structural feature using edge fringing field effect gives better design scalability compared to the conventional 3D NAND flash structures by scaling of the hole size for the vertical channel. As a result, the proposed structure is one of the candidates of Terabit 3D vertical NAND flash cell with lower bit cost and design scalability.

A Study of Three Dimensional Ion Implantation Simulator (3차원 이온 주입 시뮬레이터 개발에 관한 연구)

  • 송재복;원태영
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.11a
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    • pp.93-96
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    • 1996
  • We developed three dimensional Monte carlo ion implantation simulator which simulate distributions of impurities under the ion implantation on the tilted multi-layered layer. Our simulation reveals three dimensional shadow effect and sidewall scattering effect due to the geometrical shapes. For the evaluation of the developed three dimensional Monte carlo ion implantation simulator, calculations with 100,000 ions have been performed for the island and hole structures with a thin oxide of 100$\AA$ and nitride of 2000$\AA$. The simulation results showed that the distribution of ion decreases near the conner of the hole structure covered with a nitride layer and increases near the conner for the island structure open to oxide. Moreover, three dimensional distributions of ions were obtained with varying incident energy, tilt and rotation angle, mask depth and three-dimensional structure geometry.

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Three Dimensional Reconstruction of Cellular Structure in Drosophila Retina Using High Voltage Electron Microscopy (초고압전자현미경을 이용한 초파리 망막 세포의 3차원 구조)

  • Mun, Ji-Young;Lee, Kyung-Eun;Han, Sung-Sik
    • Applied Microscopy
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    • v.39 no.2
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    • pp.185-189
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    • 2009
  • Studies about the structure of Drosophila melanogaster retinal cell using electron microscopy have been carried out in details since 1960s. However, these results can have limitations in functional research because of two-dimensional structure. In this study, the adult retina of Drosophila melanogaster was investigated by employing high pressure freezing method, serial sections, high voltage electron microscopy, and 3-dimensional reconstruction method. From there results, mitochondria, microtubules, and nuclei were reconstructed as 3-dimensional structure using IMOD program. The 3D structure of these organelles showed that mitochondira mainly located in distal region near lens, and microtubule mainly located in distal and basal region. The 3D reconstruction of these organelles can be used for a critical evaluation in the dynamic change of cellular organelles caused by functional abnormality like retinal degeneration.

3-Dimensional Contour Line Algorithm (3차원 등가속도 처리에 관한 연구)

  • Choe, Heon-O;Lee, Seok-Sun
    • 한국기계연구소 소보
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    • s.20
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    • pp.13-20
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    • 1990
  • An algorithm is presented for 3-dimensional contour lines with a hidden line removal ~technique developed by T.L. Janssen(l). Contour line algorithm on any 3-dimensional plane cutting solid body is also shown. NUFIG(2) algorithm is adopted for searching contour lines. Test problems show well-established contour lines on the surface and also on the cutting plane of the structure.

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Evaluation of Subway Induced Vibration Effects on Building Structures (지하철 운행에 의한 건축물 진동 평가)

  • Seo, Jeong-Beom;Park, Yong-Suk;Hong, Sung-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.5
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    • pp.1107-1112
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    • 2008
  • Since vibration properties of a building structure were not easy to find out through a test, it was very difficult to in advance evaluate an influence of earthquake or other excitations on the building structure. However, currently, along with the development of the vibration analysis technique, it is possible to predict the structural performances of the buildings. The prediction of the vibration properties of the building structure has mainly employed a two-dimensional plane analysis so far, but not a three-dimensional analysis. The two-dimensional plane analysis encounters a reliability problem when the building is asymmetrical. This study has performed a three-dimensional modeling and vibration analysis on residential buildings when a subway passes below.

TAH(Total Artificial Heart) Fitting Trial Supported by 4D Volume Visualization Technique (4차원 체적 가시화 기법을 이용한 인공심장의 Fitting Trial)

  • Lee, Dong-Hyuk;Kim, Jong-Hyo;Min, Byong-Goo
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.05
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    • pp.161-162
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    • 1997
  • It is very useful to perform the surgery simulation before implanting TAH(Total Artificial Heart} in a patient. The space of chest and the shape of vessels are different from patient to patient. So, It is desirable to customize a TAH design to the anatomy structure of a patient. Several studies are performed to visualize and explain the 3D structure of heart. These studies are performed using 2-dimensional ref or mated images and simple measurement. Anatomy structure of a human heart is not so simple. It is 4dimensional structure ; 3-dimensional plus time, heart beating. 3-dimensional reconstruction schemes of medical images developed for about 10 years are usually categorized into two types of rendering technique ; surface rendering and volume rendering. Volume rendering is preferable in medical image processing field because this technique can be applied without considering the complexity of geometry and change of field of interest. The usable space in the chest of patient can be measured by 3D volume matching of patient trunk and TAH model. This space changes with time. In this research we have developed the 4-dimensional volume match program of patient and TAH model. 3-dimensional rendered set of volumes along time were used to simulate TAH fitting trial. The quantitative measurement from this simulation could be applied to customize TAH design.

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Development of Hybrid Three Dimensional Beach Deformation Model and Its Application (복합 3차원 해빈변형모델의 구축과 그 적용)

  • Shin Seung-Ho;Hong Keyyong
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.7 no.4
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    • pp.199-206
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    • 2004
  • Construction of a large offshore structure in coastal area may cause serious morphological changes for a wide region ranging from shoreline to offshore behind the structure. Shin et at. [2000] and Shin and Hong [2004] identified the sediment transport patterns behind the large offshore structure through a series of three dimensional movable bed experiments. In present study, a hybrid three dimensional beach deformation model was suggested based on those sediment transport mechanisms revealed by experimental results of the preceding studies. The model was verified by the results of the three dimensional moveable bed experiments and they agreed well not only in reappeared tombolo in shoreline side but also in the erosion and deposition region behind offshore structure. In addition, the model was applied to real beach deformation problem, which was occurred by construction of artificial offshore islands, and it validates the applicability of the model.

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