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心脏序列图像运动估计新方法:基于广义模糊梯度矢量流场的形变曲线运动估计与跟踪 被引量:15
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作者 周寿军 梁斌 陈武凡 《计算机学报》 EI CSCD 北大核心 2003年第11期1470-1478,共9页
应用动态轮廓线模型 (ACM)解决心脏运动估计问题是该领域的主要研究方法之一 .采用经典外力和传统ACM模型对感兴趣边缘进行搜索及跟踪时 ,普遍存在模型的局部适应性程度不高的缺陷 .为解决这一挑战性难题 ,该文提出了广义模糊梯度矢量流... 应用动态轮廓线模型 (ACM)解决心脏运动估计问题是该领域的主要研究方法之一 .采用经典外力和传统ACM模型对感兴趣边缘进行搜索及跟踪时 ,普遍存在模型的局部适应性程度不高的缺陷 .为解决这一挑战性难题 ,该文提出了广义模糊梯度矢量流 (GFGVF)的概念 ,并构造出一组新的Snake平衡方程 ,该方程可对心脏内部边缘逐帧进行鲁棒跟踪 .为进一步跟踪每一特征点的运动 ,该文将前一步的轮廓跟踪结果作为似然条件 ,结合一致性和连续性先验条件 ,通过最大后验概率 (MAP)的方法对整个过程进行了优化计算 .通过对MR及CT两类心脏序列图像进行运动跟踪实验并对计算结果进行多种比较 ,此方法显示了较好的鲁棒性 . 展开更多
关键词 心脏序列图像 运动估计 广义模糊梯度矢量流场 动态轮廓线模型
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Improving cam profile design optimization based on classical splines and dynamic model 被引量:8
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作者 夏必忠 刘新成 +1 位作者 尚欣 任世远 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第8期1817-1825,共9页
Cam profiles play an important part in the performance of cam mechanisms. Syntheses of cam profile designs and dynamics of cam designs are studied at first. Then, a cam profile design optimization model based on the s... Cam profiles play an important part in the performance of cam mechanisms. Syntheses of cam profile designs and dynamics of cam designs are studied at first. Then, a cam profile design optimization model based on the six order classical spline and single DOF(degree of freedom) dynamic model of single-dwell cam mechanisms is developed. And dynamic constraints such as jumps and vibrations of followers are considered. This optimization model, with many advantages such as universalities of applications, conveniences to operations and good performances in improving kinematic and dynamic properties of cam mechanisms, is good except for the discontinuity of jerks at the end knots of cam profiles which will cause vibrations of cam systems. However, the optimization is improved by combining the six order classical spline with general polynomial spline which is the so-called "trade-offs". Finally, improved optimization is proven to have a better performance in designing cam profiles. 展开更多
关键词 cam profile design spline optimization trade-off
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