• 제목/요약/키워드: Smooth function

검색결과 620건 처리시간 0.025초

산업용로봇 작업을 위한 유연한 연결경로 생성과 시간계획 (Smoothly Connected Path Generation and Time-Scheduling Method for Industrial Robot Applications)

  • 이원일;류석창;정주노
    • 제어로봇시스템학회논문지
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    • 제12권7호
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    • pp.671-678
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    • 2006
  • This article proposes a smooth path generation and time scheduling method for general tasks defined by non-smooth path segments in industrial robotic applications. This method utilizes a simple 3rd order polynomial function for smooth interpolation between non-smooth path segments, so that entire task can effectively maintain constant line speed of operation. A predictor-corrector type numerical mapping technique, which correlates time based speed profile to the smoothed path in Cartesian space, is also provided. Finally simulation results show the feasibility of the proposed algorithm.

Testing for Lack of Fit via the Generalized Neyman Smooth Test

  • Lee, Geung-Hee
    • Journal of the Korean Statistical Society
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    • 제27권3호
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    • pp.305-318
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    • 1998
  • Smoothing tests based on an L$_2$ error between a truncated courier series estimator and a true function have shown good powers for a wide class of alternatives, These tests have the same form of the Neyman smooth test whose performance depends on the selected order, a basis, the farm of estimators. We construct flexible data driven Neyman smooth tests by changing a basis, combining model selection criteria and different series estimators. A simulation study shows that the generalized Neyman smooth test with the best basis provides good power for a wider class of alternatives compared with other data driven Neyman smooth tests based on a fixed form of estimator, a fixed basis and a fixed criterion.

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Mean Shift 알고리즘을 활용한 경계선 검출의 향상 (Improvement of Edge Detection Using Mean Shift Algorithm)

  • 신성윤;이창우;이양원
    • 한국컴퓨터정보학회논문지
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    • 제14권6호
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    • pp.59-64
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    • 2009
  • 경계선 검출은 항상 원 이미지의 노이즈에 의해 영향을 받으므로 사전에 노이즈들을 제거하는 방법들이 필요하다. 그리고 Mean Shift 알고리즘은 이러한 목적에 알맞은 smooth 함수를 가지고 있고, 그래서 중요하지 않은 정보와 노이즈에 민감한 부분들을 점차 제거하는 방법들을 택하고 있다. 우선 Canny 알고리즘을 사용하여 객체의 윤곽선을 추출하는데 초점을 맞추었다. 그리고 알고리즘을 테스트 하고 이전의 단독 Canny 알고리즘보다 우수한 결과를 얻었다. 따라서 Mean Shift 알고리즘과 Canny 알고리즘이 조합된 방법은 경계선 검출 처리에 적당함을 말한다.

LIPSCHITZ REGULARITY OF M-HARMONIC FUNCTIONS

  • Youssfi, E.H.
    • 대한수학회지
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    • 제34권4호
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    • pp.959-971
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    • 1997
  • In the paper we introduce Hausdorff measures which are suitable or the study of Lipschitz regularity of M-harmonic function in the unit ball B in $C^n$. For an M-harmonic function h which satisfies certain integrability conditions, we show that there is an open set $\Omega$, whose Hausdorff content is arbitrarily small, such that h is Lipschitz smooth on $B \backslash \Omega$.

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Multiperiodic 함수를 이용한 Smooth Genus N 객체의 텍스쳐매핑 (Texture Mapping using Multiperiodic Function on the Smooth Genus N Object)

  • Hwa Jin Park
    • 한국멀티미디어학회논문지
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    • 제5권1호
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    • pp.94-104
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    • 2002
  • 본 연구는 하나의 도메인을 기반으로 하여 모델링된 Genus N 객체에 새로운 텍스쳐 매핑방법을 제안한 연구이다. 기존의 2D 텍스쳐 매핑의 문제점은 텍스쳐 도메인의 경계선이 객체상에 현저하게 나타난다는 사실이다. 이 현상은 부자연스러울 뿐 아니라 객체의 부드러운 연속성의 효과를 감소시킨다. 특히 무한대의 연속성을 가진 Genus N 객체는 경계선이 생성되지 않는 텍스쳐 매핑이 필수적이다. 이러한 텍스쳐 매핑을 위하여 multiperiodic 함수 즉, 불연속의 함수를 연속함수로 변형시키는 함수를 제안하였다. 하지만 사례에 따라 경계선이 보이는 텍스쳐가 더 사실적으로 보일 수 있다. 따라서 본 연구에서는 가중치를 이용하여 불연속과 연속 함수를 상호적으로 제어하도록 하였다.

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The calculation of stress intensity factors by the surface integral method

  • Jin, Chi-Sub;Jang, Heui-Suk;Choi, Hyun-Tae
    • Structural Engineering and Mechanics
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    • 제3권6호
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    • pp.541-553
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    • 1995
  • The determination of the stress intensity factors is investigated by using the surface integral defined around the crack tip of the structure. In this work, the integral method is derived naturally from the standard path integral J. But the use of the surface integral is also extended to the case where body forces act. Computer program for obtaining the stress intensity factors $K_I$ and $K_{II}$ is developed, which prepares input variables from the result of the conventional finite element analysis. This paper provides a parabolic smooth curve function. By the use of the function and conventional element meshes in which the aspect ratio (element length at the crack tip/crack length) is about 25 percent, relatively accurate $K_I$ and K_{II}$ values can be obtained for the outer integral radius ranging from 1/3 to 1 of the crack length and for inner one zero.

Circumferential Alignment of Vascular Smooth Muscle Cells in a Cylindrical Microchannel

  • Choi, Jong Seob;Piao, Yunxian;Kim, Kyung Hoon;Seo, Tae Seok
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.274.1-274.1
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    • 2013
  • We report the circumferential alignment of human aortic smooth muscle cells (HASMCs) in an orthogonally micropatterned circular microfluidic channel to form an in vivo-like smooth muscle cell layer. To realize a biomimetic smooth muscle cell layer which is aligned perpendicular to the axis of blood vessel, we first fabricated a half-circular polydimethylsiloxane (PDMS) microchannel by soft lithography using a convex PDMS mold. The orthogonally micro wrinkle patterns were generated inside the half-circular microchannel by stretching-releasing operation under UV irradiation. Upon UV treatment with uniaxial 40 % stretch of a PDMS substrate and releasing process, the microwrinkle patterns perpendicular to the axial direction of the circular microchannel were generated, which could guide the circumferential alignment of HASMCs successfully during cultivation. The analysis of orientation angle, shape index, and contractile protein marker expression indicates that the cultured HASMCs revealed the in vivo-like cell phenotype. Finally, we produced circular microchannels by bonding two half-circular microchannels, and cultured the HASMCs circumferentially with high alignment and viability for 5 days. These results are the first demonstration for constructing an in vivo-like 3D smooth muscle cell layer in the circular microfluidic channel which can provide novel bioassay platforms for in-depth study of HASMC biology and vascular function.

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Automatic Left Ventricle Segmentation using Split Energy Function including Orientation Term from CTA

  • Kang, Ho Chul
    • International journal of advanced smart convergence
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    • 제7권2호
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    • pp.1-6
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    • 2018
  • In this paper, we propose an automatic left ventricle segmentation method in computed tomography angiography (CTA) using separating energy function. First, we smooth the images by applying anisotropic diffusion filter to remove noise. Secondly, the volume of interest (VOI) is detected by using k-means clustering. Thirdly, we divide the left and right heart with split energy function. Finally, we extract only left ventricle from left and right heart with optimizing cost function including orientation term.

ERROR BOUNDS FOR NONLINEAR MIXED VARIATIONAL-HEMIVARIATIONAL INEQUALITY PROBLEMS

  • A. A. H. Ahmadini;Salahuddin;J. K. Kim
    • Nonlinear Functional Analysis and Applications
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    • 제29권1호
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    • pp.15-33
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    • 2024
  • In this article, we considered a class of nonlinear variational hemivariational inequality problems and investigated a gap function and regularized gap function for the problems. We discussed the global error bounds for such inequalities in terms of gap function and regularized gap functions by utilizing the Clarke generalized gradient, relaxed monotonicity, and relaxed Lipschitz continuous mappings. Finally, as applications, we addressed an application to non-stationary non-smooth semi-permeability problems.