Computed tomography(CT) plays an important role in the field of modern medical imaging. Reducing radiation exposure dose without significantly decreasing image's quality is always a crucial issue. Inspired by the ...Computed tomography(CT) plays an important role in the field of modern medical imaging. Reducing radiation exposure dose without significantly decreasing image's quality is always a crucial issue. Inspired by the outstanding performance of total variation(TV) technique in CT image reconstruction, a TV regularization based Bayesian-MAP(MAP-TV) is proposed to reconstruct the case of sparse view projection and limited angle range imaging. This method can suppress the streak artifacts and geometrical deformation while preserving image edges. We used ordered subset(OS) technique to accelerate the reconstruction speed. Numerical results show that MAP-TV is able to reconstruct a phantom with better visual performance and quantitative evaluation than classical FBP,MLEM and quadrate prior to MAP algorithms. The proposed algorithm can be generalized to cone-beam CT image reconstruction.展开更多
提出一种改进的粒子滤波SLAM(simultaneous localization and map building)同时定位和地图创建实现方法。改进方法让机器人大约行进10步完成基于局部已创建地图下的粒子滤波定位后,再利用激光传感器探测环境并更新创建的地图;同时在利...提出一种改进的粒子滤波SLAM(simultaneous localization and map building)同时定位和地图创建实现方法。改进方法让机器人大约行进10步完成基于局部已创建地图下的粒子滤波定位后,再利用激光传感器探测环境并更新创建的地图;同时在利用粒子滤波定位时,使粒子只分布在由航位推算法得出的机器人位姿附近,从而可有效地减少粒子的数量。实验结果表明,与标准的粒子滤波SLAM算法比较,改进算法提高了机器人SLAM过程中定位和地图创建的精度和实时性,并为移动机器人在室外未知环境同时定位和地图创建提供了新方法。展开更多
基金National Natural Science Foundation of Chinagrant number:30970866+3 种基金Guangzhou Municipal Science and Technology Projectgrant number:llBppZLjj2120029Guangdong Strategic Emerging Industry Core Technology Researchgrant number:2011A081402003
文摘Computed tomography(CT) plays an important role in the field of modern medical imaging. Reducing radiation exposure dose without significantly decreasing image's quality is always a crucial issue. Inspired by the outstanding performance of total variation(TV) technique in CT image reconstruction, a TV regularization based Bayesian-MAP(MAP-TV) is proposed to reconstruct the case of sparse view projection and limited angle range imaging. This method can suppress the streak artifacts and geometrical deformation while preserving image edges. We used ordered subset(OS) technique to accelerate the reconstruction speed. Numerical results show that MAP-TV is able to reconstruct a phantom with better visual performance and quantitative evaluation than classical FBP,MLEM and quadrate prior to MAP algorithms. The proposed algorithm can be generalized to cone-beam CT image reconstruction.
文摘提出一种改进的粒子滤波SLAM(simultaneous localization and map building)同时定位和地图创建实现方法。改进方法让机器人大约行进10步完成基于局部已创建地图下的粒子滤波定位后,再利用激光传感器探测环境并更新创建的地图;同时在利用粒子滤波定位时,使粒子只分布在由航位推算法得出的机器人位姿附近,从而可有效地减少粒子的数量。实验结果表明,与标准的粒子滤波SLAM算法比较,改进算法提高了机器人SLAM过程中定位和地图创建的精度和实时性,并为移动机器人在室外未知环境同时定位和地图创建提供了新方法。
