• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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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.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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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.

• 대한건축학회논문집:계획계
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• 제34권2호
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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.

• International Journal of CAD/CAM
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• 제9권1호
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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.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2006년도 PARALLEL CFD 2006
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• pp.63-65
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• 2006

• 마이크로전자및패키징학회지
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• 제15권2호
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• pp.63-67
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• 2008

전자산업의 소형화와 경량화 추세에 맞추어 최근 집적 칩(IC)이나 패키지를 적층시키는 삼차원 집적화(3D integration) 기술 개발은 차세대 핵심기술로 중요시되고 있다. 본 연구에서는 삼차원 집적화 공정 기술 중 하나인 초박막 실리콘 웨이퍼 연삭(grinding)공정이 웨이퍼 표면에 미치는 영향에 대해서 조사하였다. 실리콘 웨이퍼를 약 $30{\mu}m$과 $50{\mu}m$ 두께까지 연삭한 후, 미세연삭(fine grinding) 단계까지 처리된 시편을 건식 연마(dry polishing) 또는 습식 애칭(wet etching)으로 표면 처리된 시편들과 비교 분석하였다. 박막 웨이퍼 두께는 전계방시형 주사전자현미경과 적외선 분광기로 측정하였고, 표면 특성 분석을 위해선 표면주도(roughness), 표면손상(damage), 경도를 원자현미경, 투과정자현미경 그리고 나노인덴터(nano-indentor)를 이용하여 측정하였다. 표면 처리된 시편의 특성이 표면 처리되지 않은 시편보다 표면주도와 표면손상 등에서 현저히 우수함을 확인 할 수 있었으나, 경도의 경우 표면 처리의 유무에 관계없이 기존의 벌크(bulk)실리콘 웨이퍼와 오차범위 내에서 동일한 것으로 보였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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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.

• 대한기계학회논문집A
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• 제33권2호
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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.

• 한국통신학회논문지
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• 제18권1호
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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.

• 대한임베디드공학회논문지
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• 제17권2호
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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.