• Title/Summary/Keyword: fitting

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Ideal Phase map Extraction Method and Filtering of Electronic Speckle Pattern Interferometry (ESPI 에서의 이상적인 위상도 추출과 필터링 방법)

  • 유원재;이주성;강영준;채희창
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.235-238
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    • 2001
  • Deformation phase can be obtained by using Least-Square Fitting. In extraction of phase values, Least-Square Fitting is superior to usual method like as 2, 3, 4-Bucket Algorithm. That can extract almost noise-free phase and retain 2$\pi$discontinuities. But more fringe in phase map, 2$\pi$ discontinuities is destroyed when that is filtered and reconstruction of deformation is not reliable. So, we adapted Least-Square Fitting using an isotropic window in dense fringe. using Sine-Cosine filter give us perfect 2$\pi$discontinuities information. We showed the process and result of extraction of phase map and filtering in this paper.

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Ideal Phase map Extraction Method and Filtering of Electronic Speckle Pattern Interferometry (전자 스페클 간섭법에서의 이상적인 위상도 추출과 필터링 방법)

  • 강영준;이주성;박낙규;권용기
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.12
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    • pp.20-26
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    • 2002
  • Deformation phase can be obtained by using Least-Square fitting. In extraction of phase values, Least-Square Fitting is superior to usual method such as 2, 3, 4-Bucket Algorithm. That can extract almost noise-free phase and retain 2 $\pi$ discontinuities. But more fringes in phase map, 2 $\pi$ discontinuities are destroyed when that are filtered and reconstruction of deformation is not reliable. So, we adapted Least-Square fitting using an isotropic window in dense fringe. Using Sine/cosine filter give us perfect 2 $\pi$ discontinuities information. We showed the process and result of extraction of phase map and filtering in this paper.

Approximate Lofting by B-spline Curve Fitting Based on Energy Minimization (에너지 최소화에 근거한 B-spline curve fitting을 이용한 근사적 lofting 방법)

  • 박형준;김광수
    • Korean Journal of Computational Design and Engineering
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    • v.4 no.1
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    • pp.32-42
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    • 1999
  • Approximate lofting or skinning is one of practical surface modeling techniques well used in CAD and reverse engineering applications. Presented in this paper is a method for approximately lofting a given set of curves wihin a specified tolereance. It is based on refitting input curves simultaneously on a common knot vector and interpolating them to get a resultant NURBS surface. A concept of reducing the number of interior knots of the common knot vector is well adopted to acquire more compact representation for the resultant surface. Energy minimization is newly introduced in curve refitting process to stabilize the solution of the fitting problem and get more fair curve. The proposed approximate lofting provides more smooth surface models and realizes more efficient data reduction expecially when the parameterization and compatibility of input curves are not good enough. The method has been successfully implemented in a new CAD/CAM product VX Vision? of Varimetrix Corporation.

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Measuring Structural Vibration from Video Signal Using Curve Fitting (영상 신호에서 커브 피팅을 이용한 구조물 진동 측정)

  • Jeon, Hyeong-Seop;Choi, Young-Chul;Park, Jong-Won
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.19 no.9
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    • pp.943-949
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    • 2009
  • Many studies for measuring vibration using image signal are suggested. These methods can measure vibration of multi-points simultaneously. However, it has the disadvantage that is very sensitive to an environment. If the measured environment is not good, image signals can be measured including much background noise. So, it is difficult to obtain accurate vibration from the measured image signals. Another problem is that camera imaging has a resolution limit. Because the resolution of the camera image is relatively much lower than that of a data acquisition system, accurate measuring vibration cannot be performed. In this paper, we proposed the enhanced technique for measuring vibration using camera signal. The key word of this paper is a curve fitting. The curve fitting can exactly detect the measurement line of interested object. So, we can measure the vibration in noisy environment. Also, it can overcome the resolution limit.

An Efficient Design Method of RF Filters via Optimized Rational-Function Fitting, without Coupling-Coefficient Similarity Transformation (무 결합계수-회전변환의, 최적화된 유리함수 Fitting에 의한 효율적인 RF대역 여파기 설계기법)

  • Ju Jeong-Ho;Kang Sung-Tek;Kim Hyeong-Seok
    • 한국정보통신설비학회:학술대회논문집
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    • 2006.08a
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    • pp.202-204
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    • 2006
  • A new method is presented to design RF filters without the Similarity Transform of their coupling coefficient matrix as circuit parameters which is very tedious due to pivoting and deciding rotation angles needed during the iterations. The transfer function of a filter is directly used for the design and its desired form is derived by the optimized rational-function fitting technique. A 3rd order Coaxial Lowpass filter and an 8th order dual-mode elliptic integral function response filter are taken as an example to validate the proposed method.

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Conservative Quadratic RSM combined with Incomplete Small Composite Design and Conservative Least Squares Fitting

  • Kim, Min-Soo;Heo, Seung-Jin
    • Journal of Mechanical Science and Technology
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    • v.17 no.5
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    • pp.698-707
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    • 2003
  • A new quadratic response surface modeling method is presented. In this method, the incomplete small composite design (ISCD) is newly proposed to .educe the number of experimental runs than that of the SCD. Unlike the SCD, the proposed ISCD always gives a unique design assessed on the number of factors, although it may induce the rank-deficiency in the normal equation. Thus, the singular value decomposition (SVD) is employed to solve the normal equation. Then, the duality theory is used to newly develop the conservative least squares fitting (CONFIT) method. This can directly control the ever- or the under-estimation behavior of the approximate functions. Finally, the performance of CONFIT is numerically shown by comparing its'conservativeness with that of conventional fitting method. Also, optimizing one practical design problem numerically shows the effectiveness of the sequential approximate optimization (SAO) combined with the proposed ISCD and CONFIT.

A Study on the COntour Machining of Text using CNC Laser Machine (CNC레이저 가공기를 이용한 활자체 가공에 관한 연구)

  • 구영회
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.10a
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    • pp.554-559
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    • 1999
  • The purpose of this study is the machining of texture shapes by the contour fitting data. The hardware of the system comprises PC and scanning system, CO2 laser machine. There are four steps, (1) text image loading using scanning shapes or 2D image files, (2) generation of contour fitting data by the line and arc, cubic Bezier curve, (3) generation of NC code from the contouring fitting data, (4) machining by the DNC system. It is developed a software package, with which can conduct a micro CAM system of CNC laser machine in the PC without economical burden.

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Compar ison of Level Set-based Active Contour Models on Subcor tical Image Segmentation

  • Vongphachanh, Bouasone;Choi, Heung-Kook
    • Journal of Korea Multimedia Society
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    • v.18 no.7
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    • pp.827-833
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    • 2015
  • In this paper, we have compared three level set-based active contour (LSAC) methods on inhomogeneous MR image segmentation which is known as an important role of brain diseases to diagnosis and treatment in early. MR image is often occurred a problem with similar intensities and weak boundaries which have been causing many segmentation methods. However, LSAC method could be able to segment the targets such as the level set based on the local image fitting energy, the local binary fitting energy, and local Gaussian distribution fitting energy. Our implemented and tested the subcortical image segmentations were the corpus callosum and hippocampus and finally demonstrated their effectiveness. Consequently, the level set based on local Gaussian distribution fitting energy has obtained the best model to accurate and robust for the subcortical image segmentation.

A Digital Hearing Aid with 8-band Curvilinear Loudness Fitting (8대역 비선형 라우드니스 교정 디지털 보청기)

  • Park, Y.C.;Kim, D.W.;Kim, W.K.;Park, S.I.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.79-82
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    • 1997
  • In this paper, a body-worn type digital hearing aid (DHA) based on a dedicated DSP chip is developed. A fitting software running on a PC supported by the Win95 OS is also developed. The fitting protocol is based on the NAL-R procedure applied to eight frequency bands, but it is designed to support a curvilinear fitting to cope with the nonlinear perception of hearing-impaired listeners. Preliminary subjective tests regarding the speech intelligibility and perceived quality revealed that the new DHA could be of benefit to hearing aid users.

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3D Pattern Construction and Its Application to Tight-fitting Garments for Comfortable Pressure Sensation

  • Jeong Yeon-Hee;Hong Kyung-Hi;Kim See-Jo
    • Fibers and Polymers
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    • v.7 no.2
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    • pp.195-202
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    • 2006
  • Tight-fitting clothing pattern reflecting the accurate information of the 3D body shape has been one of the challenges for garment industry, however, fitting problems still exist. The objectives of the paper is to develop a 2D pattern which fits tightly to the 3D human scan data for sports suits that need comfort and function for maximum performance. In this study, the user graphic interface application software for the semi-automatic garment pattern generation has been implemented using the triangle simplification scheme together with 2D projections of free-falling of 3D surface polygons keeping the original 3D surface area preservation. A typical application of the developed pattern to the functional body suits is presented and verification of the proposed method is also provided.