• Title/Summary/Keyword: surface integration

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Performance Characteristics of Time Delay and Integration(TDI) Satellite Imager for Altitude Change and Line-Of-Sight Tilt over Spherical Earth Surface

  • Cho, Young-Min
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.216-221
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    • 2002
  • A spherical Earth surface is used fur realistic analysis of the geometrical performance characteristics about the variation of satellite altitude and 2-dimensional line-of-sight(LOS) tilt angle in a satellite imager using Time Delay and Integration(TDI) technique with fixed integration time. In the spherical Earth surface model TDI synchronization using LOS tilt is investigated as a solution to compensate geometric performance degradation due to altitude decrease. This result can be used fur a TDI CCD imager with variable integration time in a certain as well.

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Trimmed surface analysis based on T-spline FEM (T-스플라인 유한요소해석을 이용한 트림 곡면 해석)

  • Kim, Hyun-Jung;Seo, Yu-Deok;Youn, Sung-Kie
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.612-617
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    • 2008
  • In this present work, trimmed surface analysis for the 2D elasticity problem is presented. The main benefit of the proposed method is that no additional modeling for analysis of a trimmed surface is necessary. As the first attempt to deal with a trimmed surface in spline FEM, the information of the trimming curve and trimmed surface exported from CAD system is directly utilized for analysis. For this, trimmed elements are searched through employing projection scheme. For the integration of the trimmed elements, NURBSenhanced integration scheme which is used in NEFEM is adopted. The quadtree refinement of integration cell is performed for the complicated trimmed cases. The information of trimming curve is used for obtaining integration points as well as constructing stiffness matrix. The robustness and effectiveness of the proposed method are investigated by presenting various numerical examples.

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A Study on the Integration of Objects and Environment in the Surface with Changing Materiality of Prada Aoyama Epicenter (프라다 아오야마 에피센터 건축에서 나타나는 환경과 사물과 통합되는 다층적 물질성의 표면에 관한 연구)

  • Kim, Heebum;Kang, Jae-Hyuk;Choi, Weonah
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.34 no.2
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    • pp.33-40
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    • 2018
  • The purpose of this study was to analyze integration of the surface of Prada Aoyama Epicenter by Herzog & de Meuron. To understand various aspects of surfaces & constituents related, each elevations are analyzed minutely by distance both inside and outside. The results of this study were as follows; the individual surface of Prada Aoyama Epicenter sets a multi-layered relationship with the actual environment. Their architectural surface still has a significance in presenting a way of creating a building along with everyday surroundings.

An Optimization-based Computational Method for Surface Fitting to Update the Geometric Information of An Existing B-Rep CAD Model

  • Louhichi, Borhen;Aifaoui, Nizar;Hamdi, Mounir;BenAmara, Abdelmajid;Francois, Vincent
    • International Journal of CAD/CAM
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    • v.9 no.1
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    • pp.17-24
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    • 2010
  • For several years, researchers have focused on improving the integration of the CAD, CAM and Analysis through a better communication between the various analysis tools. This tendency to integrate the CAD/Analysis and automation of the corresponding processes requires data sharing between the various tasks using an integrated product model. We are interested in this research orientation to CAD/CAM/Analysis integration by rebuilding the CAD model (BREP), starting from the Analysis results (deformed mesh). Because this problem is complex, it requires to be split into several complementary parts. This paper presents an original interoperability process between the CAD and CAE. This approach is based on a new technique of rebuilding the CAD surface model (Nurbs, Bezier, etc.) starting from triangulation (meshed surface) as a main step of the BREP solid model. In our work, the advantages of this approach are identified using a centrifugal pump example.

Effect of Si Wafer Ultra-thinning on the Silicon Surface for 3D Integration (삼차원 집적화를 위한 초박막 실리콘 웨이퍼 연삭 공정이 웨이퍼 표면에 미치는 영향)

  • Choi, Mi-Kyeung;Kim, Eun-Kyung
    • Journal of the Microelectronics and Packaging Society
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    • v.15 no.2
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    • pp.63-67
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    • 2008
  • 3D integration technology has been a major focus of the next generation of IC industries. In this study Si wafer ultra-thinning has been investigated especially for the effect of ultra-thinning on the silicon surface. Wafers were grinded down to $30{\mu}m\;or\;50{\mu}m$ thickness and then grinded only samples were compared with surface treated samples in terms of surface roughness, surface damages, and hardness. Dry polishing or wet etching treatment has been applied as a surface treatment. Surface treated samples definitely showed much less surface damages and better roughness. However, ultra-thinned Si samples have the almost same hardness as a bulk Si wafer.

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Application and Development of Integration Technique to Generate Land-cover and Soil Moisture Map Using High Resolution Optical and SAR images

  • Kim Ji-Eun;Park Sang-Eun;Kim Duk-jin;Kim Jun-su;Moon Wooil M.
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.497-500
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    • 2005
  • Research and development of remote sensing technique is necessary so that more accurate and extensive information may be obtained. To achieve this goal, the synthesized technique which integrates the high resolution optic and SAR image, and topographical information was examined to investigate the quantitative/qualitative characteristics of the Earth's surface environment. For this purpose, high-precision DEMs of Jeju-Island was generated and data fusion algorithm was developed in order to integrate the multi-spectral optic and polarimetric SAR image. Three dimensional land-cover and two dimensional soil moisture maps were generated conclusively so as to investigate the Earth's surface environments and extract the geophysical parameters.

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T-spline FEA for Trimmed NURBS Surface (트림 NURBS 곡면의 T-스플라인 유한요소해석)

  • Kim, Hyun-Jung;Seo, Yu-Deok;Youn, Sung-Kie
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.33 no.2
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    • pp.135-144
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    • 2009
  • In this present work, spline FEA for the trimmed NURBS surface of the 2D linear elasticity problem is presented. The main benefit of the proposed method is that no additional efforts for modeling of trimmed NURBS surfaces are needed and the information of the trimming curves and trimmed surfaces exported from the CAD system can be directly used for analysis. For this, trimmed elements are searched by using NURBS projection scheme. The integration of the trimmed elements is performed by using the NURBS-enhanced integration scheme. The formulation of constructing stiffness matrix of trimmed elements is presented. In this formulation, the information of the trimming curve is used for calculating the Jacobian as well as for obtaining integration points. The robustness and effectiveness of the proposed method are investigated through various numerical examples.

An Approach for Efficient Numerical Integration of the Sommerfeld Type Integrals Pertinent to the Microstrip Surface Green's Function (Microstrip 표면 Green 함수에 관한 Sommerfeld 형 적분들의 효과적인 수치 적분법)

  • 최익권
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.1
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    • pp.143-149
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    • 1993
  • An approach is presented for efficient numerical integration of the Sormnerfeld type integrals pertinent to the microstrip surface Green's function arising in the problem of an electric current point source on an infinite planar grounded dielectric substrate. This approach, valid for both lossless and lossy dielectric substrates, is based on the deformation of the integration contour via a coordinate transformation and Cauchy's residue theory, and identifies clearly the effects of surface waves. I ts useful application is in a rigorous moment method analysis of micros trip antenna arrays and microstrip guided wave structures. The efficiency and the usefulness of the present approach are emphasized through some numerical calculations of the impedance matrix elements with associated CPU times.

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New Protocol at Fast Scan Mode for Sea-surface Small Target Detection

  • Cha, Sangbin;Park, Sanghong;Jung, Jooho;Choi, Inoh
    • IEMEK Journal of Embedded Systems and Applications
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    • v.17 no.2
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    • pp.101-107
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    • 2022
  • In this article, we propose a new protocol at fast scan mode for a sea-surface small target detection. The conventional fast scan mode is composed of coherent intrascan integration to suppress sea clutter and non-coherent interscan integration to exclude sea spikes. The proposed method realizes the coherent interscan integration by the new Fourier relationship between carrier-frequency and initial-radial-range, which can be analytically derived by using multiple carrier frequencies at fast scan mode, leading to improved detection performance, compared to the conventional non-coherent methods. In simulations, our proposed method is verified.