Digital image design is one of advanced technique in textile design. The investigation into digital Jacquard textile design in the colorful mode is one form of research in digital Jacquard fabric design, which aimed a...Digital image design is one of advanced technique in textile design. The investigation into digital Jacquard textile design in the colorful mode is one form of research in digital Jacquard fabric design, which aimed at expanding past and present jacquard design and production methods towards innovative ends. In this paper, the design principles and design methods for unconventional digital Jacquard fabric design in colorful mode have been analyzed based on the new technologies and computer applied color theory. The results of this study will enhance further research in the area of digital textile.展开更多
Jacquard image segmentation is one of the primary steps in image analysis for jacquard pattern identification. The main aim is to recognize homogeneous regions within a jacquard image as distinct, which belongs to dif...Jacquard image segmentation is one of the primary steps in image analysis for jacquard pattern identification. The main aim is to recognize homogeneous regions within a jacquard image as distinct, which belongs to different patterns. Active contour models have become popular for finding the contours of a pattern with a complex shape. However, the performance of active contour models is often inadequate under noisy environment. In this paper, a robust algorithm based on the Mumford-Shah model is proposed for the segmentation of noisy jacquard images. First, the Mumford-Shah model is discretized on piecewise linear finite element spaces to yield greater stability. Then, an iterative relaxation algorithm for numerically solving the discrete version of the model is presented. In this algorithm, an adaptive triangular mesh is refined to generate Delaunay type triangular mesh defined on structured triangulations, and then a quasi-Newton numerical method is applied to find the absolute minimum of the discrete model. Experimental results on noisy jacquard images demonstrated the efficacy of the proposed algorithm.展开更多
针对大型提花机承受载荷时易发生弯曲变形导致拉刀提升高度不够,使直针钩子无法被电磁装置吸附的问题,首先对拉刀结构、载荷以及曲柄滑块驱动机构运动情况进行分析。其次,基于变截面梁理论和结构优化的方法,采用非均匀有理B样条(Non-Uni...针对大型提花机承受载荷时易发生弯曲变形导致拉刀提升高度不够,使直针钩子无法被电磁装置吸附的问题,首先对拉刀结构、载荷以及曲柄滑块驱动机构运动情况进行分析。其次,基于变截面梁理论和结构优化的方法,采用非均匀有理B样条(Non-Uniform Rational B-Splines,NURBS)曲线表达拉刀侧面、截面形状,通过数值方法计算拉刀截面惯性矩函数、弯矩函数,并通过有限差分法计算拉刀变形量。通过有限元方法(Finite Element Method,FEM)、等效为等截面梁的方法对挠度计算方法进行验证,误差在10%以内。最后,以最小质量为目标,采用原-对偶不可行内点算法对拉刀结构进行优化。优化结果表明,相较于优化初值模型,拉刀质量减小约17%,最大挠度减小约2667%。展开更多
文摘Digital image design is one of advanced technique in textile design. The investigation into digital Jacquard textile design in the colorful mode is one form of research in digital Jacquard fabric design, which aimed at expanding past and present jacquard design and production methods towards innovative ends. In this paper, the design principles and design methods for unconventional digital Jacquard fabric design in colorful mode have been analyzed based on the new technologies and computer applied color theory. The results of this study will enhance further research in the area of digital textile.
基金Project (No. 2003AA411021) supported by the Hi-Tech Research andDevelopment Program (863) of China
文摘Jacquard image segmentation is one of the primary steps in image analysis for jacquard pattern identification. The main aim is to recognize homogeneous regions within a jacquard image as distinct, which belongs to different patterns. Active contour models have become popular for finding the contours of a pattern with a complex shape. However, the performance of active contour models is often inadequate under noisy environment. In this paper, a robust algorithm based on the Mumford-Shah model is proposed for the segmentation of noisy jacquard images. First, the Mumford-Shah model is discretized on piecewise linear finite element spaces to yield greater stability. Then, an iterative relaxation algorithm for numerically solving the discrete version of the model is presented. In this algorithm, an adaptive triangular mesh is refined to generate Delaunay type triangular mesh defined on structured triangulations, and then a quasi-Newton numerical method is applied to find the absolute minimum of the discrete model. Experimental results on noisy jacquard images demonstrated the efficacy of the proposed algorithm.
文摘针对大型提花机承受载荷时易发生弯曲变形导致拉刀提升高度不够,使直针钩子无法被电磁装置吸附的问题,首先对拉刀结构、载荷以及曲柄滑块驱动机构运动情况进行分析。其次,基于变截面梁理论和结构优化的方法,采用非均匀有理B样条(Non-Uniform Rational B-Splines,NURBS)曲线表达拉刀侧面、截面形状,通过数值方法计算拉刀截面惯性矩函数、弯矩函数,并通过有限差分法计算拉刀变形量。通过有限元方法(Finite Element Method,FEM)、等效为等截面梁的方法对挠度计算方法进行验证,误差在10%以内。最后,以最小质量为目标,采用原-对偶不可行内点算法对拉刀结构进行优化。优化结果表明,相较于优化初值模型,拉刀质量减小约17%,最大挠度减小约2667%。