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This paper deals with the issues of development and implementation of a real-time NURBS interpolator for a six-axis robot. Using an open-architecture controller system as a testbed, a real-time NURBS curve interpolator was developed, implemented and tested. Sample runs were conducted with the resulting trajectories measured in real-time during robot motion. The resulting trajectories are analyzed, discussed and compared with those from a commonly used point-to-point approximation technique. The real-time NURBS curve interpolator's feasibility, advantages and related issues are also discussed. 相似文献
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In this paper a simple preparative method for isolation and purification of ginkgolides A and B was developed,As starting material,a commercially available standardized ginkgo extract (EGb761,containing 24% flavonoid and 6% terpene trilactones) was used,After a pretreatment step,optimized by the uniform design method ,the concentrated intermediate extract with high content of GA and gb( 90%) was separated into the individual terpenes by preparative liquid chromatography eluted with petroleum ether-ethylacetate,Analysis of products was carried out by means of HPLC-ELSD(evaporative light -scattering detector),The results show that ginkgolides A and B are obtained in higher yield and better purity. 相似文献
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M.?MelgosaEmail author R.?Huertas E.?Hita J.?M.?Roa F.?J.?Heredia J.?Alba M.?J.?Moyano 《Journal of the American Oil Chemists' Society》2004,81(4):323-330
A new color scale was developed from a broad data set of 1700 virgin olive oil samples over four crop seasons, which can be
considered highly representative of the whole color range of virgin olive oils available in Spain. This color scale provides
a new set of 60 color standards, improving the results achieved by the old 60-color standards proposed by the bromthymol blue
method. Seeking the greatest possibility of including a near match between colors of virgin olive oils and proposed standards,
we developed our new color scale using a recent uniform color space, with standards placed in a regular rhombohedral lattice
like the one employed by the Uniform Color Scales of the Optical Society of America. The average color difference between
each of the 1700 virgin olive oils and its nearest standard is reduced from 8.17 CIELAB units, using the bromthymol blue standards,
to 3.99 CIELAB units using the new standards. Within a color tolerance of 7.0 CIELAB units, 93.2% of our virgin olive oils
can be classified with the new standards, but only 59.1% with the bromthymol blue ones. In the interest of future adoption,
the performance of the new color standards should be tested by industry and researchers. 相似文献
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借助Lyapunov函数稳定性理论和最优化理论研究了永磁同步电动机系统解的界,得到了它的界估计。通过计算机模拟,数值模拟验证了计算理论的可行性。 相似文献
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从四边固定正方形板受均布载荷的经典问题入手,结合不同类型单元的特点,探讨应用三维实体单元分析薄壁箱型结构时应注意的几个问题,纠正三维实体单元分析和应用的误区,为提高结构分析计算结果精度提供参考. 相似文献