• 제목/요약/키워드: Geometric Program

검색결과 448건 처리시간 0.024초

마스크 레이아웃의 등가 회로 추출을 위한 블록 분할 기법 (A Block Disassembly Technique for Equivalent Circuit Extraction of Mask Layouts)

  • 손영찬;주리아;박석홍;유상대
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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    • pp.246-249
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    • 2000
  • In this paper, we describe an automated extraction program that transforms a mask layout into an approximated equivalent circuit information suitable for circuit simulation, and that extract the geometric parameters of stacked MOSFETs and the distributed RCs of layout blocks. To extract equivalent circuit from mask layout, we propose new block disassembly technique capable of accurate computations of distributed RCs at branch point, using vectorized edges which represent the outline of an individual polygon.

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Estimation of Effective Coil Length of Superconducting Generator using 3D FEM

  • Shin, Pan-Seok;Park, Doh-Young
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • 제12B권1호
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    • pp.7-12
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    • 2002
  • This paper presents a method to estimate an effective length of a 1000-kVA superconducting generator using three-dimensional FE analysis. Flux linkage of stator coil and the induced voltage are calculated with FEM program and Faraday's law. An effective length of the stator coil is estimated using the calculated voltage and geometric configurationn of the machine. In order to verify the estimation method, 30-kVA superconducting generator is built and tested. The test result agrees reasonably well with the estimation.

Inelastic buckling of tapered members with accumulated strain

  • Kim, M.C.;Lee, G.C.;Chang, K.C.
    • Structural Engineering and Mechanics
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    • 제3권6호
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    • pp.611-622
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    • 1995
  • This paper is concerned with inelastic load carrying capacity of tapered steel members with or without accumulated plastic strains resulted from previous loading histories. A finite element program is developed using stiffness matrices of tapered members and is applicable for analyses with material and geometric nonlinearity. Results of analyses are compared with other available solutions and with experimental results.

일반적인 NC 공작기계의 CNC화에 관한 연구 (A study on the development of CNC machine using conventional NC)

  • 하성도;이종원;김상국
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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    • pp.237-241
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    • 1987
  • In this paper, the BTR (Behind the Tape Reader) type communication unit which interfaces the IEBM PC/XT to the FANUC 5M NC controller is developed, making it possible to send NC part program from the memory of IBM PC/XT to the NC controller. As an example of integration of CAD and CAM technologies, the machining of a two dimensional hand-written free line which incorporates the processes of geometric data acquisition using a digitizing tablet, automatic part programming and control of NC milling machine operation is demonstrated.

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면진 고무 베어링의 안정성에 대하여 (On the stability of Rubber Isolation Bearings)

  • 이종세
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 1998년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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    • pp.85-92
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    • 1998
  • As an analytical approach, the area reduction formula of rubber bearings has been proposed to account for the reduction in bucking load due to shear. The result obtained from the formula is presumed to be conservative but the degree of conservatism is unknown. This paper describes a numerical study which aims at determining the effect of high shear strain on the critical load of rubber bearings using a finite element analysis program. The results from the finite element analysis which accounts for both the material and geometric non-linearities are compared against the theoretical results in order to examine the validity of the theoretical formulas.

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THE MINIMUM VARIANCE UNBIASED ESTIMATION OF SYSTEM RELIABILITY

  • Park, C.J.;Kim, Jae-Joo
    • 대한산업공학회지
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    • 제4권1호
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    • pp.29-32
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    • 1978
  • We obtain the minimum variance unbiased estimate of system reliability when a system consists of n components whose life times are assumed to be independent and identically distributed either negative exponential or geometric random variables. For the case of a negative exponential life time, we obtain the minimum variance unbiased estimate of the probability density function of the i-th order statistic.

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접선 캠의 형상설계 및 운동해석을 위한 CAD시스템 개발 (CAD System Development for Geometric Design and Motion Analysis of Tangential Cam)

  • 조성철;송정섭
    • 한국안전학회지
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    • 제10권3호
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    • pp.42-46
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    • 1995
  • To purpose of this study is to model design and motion analysis of tangential cam mechanism using personal computer system. The CAD(Computer Aided Design) system used in this study was constructed with CPU(Central Processing Unit) 80486, RAM(Random Access Memory) 8M, CGA graphic card. By using developed program for tangential cam mechanism, we designed tangential cam models and analysed displacement, velocity, acceleration of follower.

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정상 척추체 모델을 이용한 척추측만증 모델 자동 생성 프로그램 개발 (Development of a Special Program for Automatic Generation of Scoliotic Spine FE Model with a Normal Spine Model)

  • 유한규;김영은
    • 한국정밀공학회지
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    • 제23권3호
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    • pp.187-194
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    • 2006
  • Unexpected postoperative changes, such as growth in rib hump and shoulder unbalance, have been occasionally reported after corrective surgery for scoliosis. However there has been neither experimental data fer explanation of these changes, nor the suggestion of optimal correction method. Therefore, the numerical study was designed to investigate the post-operative changes of vertebral rotation and rib cage deformation after the corrective surgery of scoliosis. A mathematical finite element model of normal spine including rib cage, sternum, both clavicles, and pelvis was developed with anatomical details. In this study, we also developed a special program which could convert a normal spine model to a desired scoliotic spine model automatically. A personalized skeletal deformity of scoliosis model was reconstructed with X-ray images of a scoliosis patient from the normal spine structures and rib cage model. The geometric mapping was performed by translating and rotating the spinal column with an amount analyzed from the digitized 12 built-in coordinate axes in each vertebral image. By utilizing this program, problems generated in mapping procedure such as facet joint overlapping, vertebral body deformity could be automatically resolved.

Randomized Hough 변환을 이용한 타원형 액적의 형상 검출 (Shape Detection of Ellipsoidal Droplets Using Randomized Hough Transform)

  • 추연준;강보선
    • 대한기계학회논문집B
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    • 제27권10호
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    • pp.1508-1515
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    • 2003
  • In this study, the image processing program for deducing parameters of the elliptic shape of the partially overlapped liquid droplets was developed using the randomized Hough transform and the parameter decomposition. The procedure for the shape detection consists of three steps. For the first step, the candidate centers of ellipses are determined by the geometric property of the ellipse. Next, the rest parameters are estimated by the randomized Hough transform. In the final step for the post-processing, optimally approximated parameters of ellipses are determined. The developed program was applied to the simulated overlapped ellipses, real overlapped droplets, and real spray droplets. The shape detection was very excellent unless there existed inherent problems in original images. Moreover, this method can be used as an effective separating method for the overlapped small particles.

딥드로잉 판넬의 단면성형 해석을 위한 유한요소법/기하학힘평형법에 관한 연구 (A Study on the FEM/GEM for Sectional Analysis of Deep Drawing Panels)

  • 김종필;금영덕;이종문
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1993년도 추계학술대회 논문집
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    • pp.212-217
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    • 1993
  • A 2-dimensional FEM/GEM program was developed for analyzing forming processes of an arbitrarily shaped draw-die, in which plane strain condition is assumed and linear line elements are employed. FEM formulation adopted a new algorithm for solving force equilibrium as well as non-penetration condition simultaneously. For the case of numerical divergence at nearly final forming stages and the initial guess in Newton-Raphson iterations, geometric force equilibrium method(GEM) is also introduced. The developed program was tested with the simulation of stamping processes of automotive bonnet inner pannel in order to verify the usefulness and validity of FEM/GEM formulation.

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