Highly programmable shape morphing of 4D-printed micro/nanostructures is urgently desired for applications in robotics and intelligent systems.However,due to the lack of autonomous holistic strategies throughout the t...Highly programmable shape morphing of 4D-printed micro/nanostructures is urgently desired for applications in robotics and intelligent systems.However,due to the lack of autonomous holistic strategies throughout the target shape input,optimal material distribution generation,and fabrication program output,4D nanoprinting that permits arbitrary shape morphing remains a challenging task for manual design.In this study,we report an autonomous inverse encoding strategy to decipher the genetic code for material property distributions that can guide the encoded modeling toward arbitrarily pre-programmed 4D shape morphing.By tuning the laser power of each voxel at the nanoscale,the genetic code can be spatially programmed and controllable shape morphing can be realized through the inverse encoding process.Using this strategy,the 4D-printed structures can be designed and accurately shift to the target morphing of arbitrarily hand-drawn lines under stimulation.Furthermore,as a proof-of-concept,a flexible fiber micromanipulator that can approach the target region through pre-programmed shape morphing is autonomously inversely encoded according to the localized spatial environment.This strategy may contribute to the modeling and arbitrary shape morphing of micro/nanostructures fabricated via 4D nanoprinting,leading to cutting-edge applications in microfluidics,micro-robotics,minimally invasive robotic surgery,and tissue engineering.展开更多
针对MPEG-4（Moving Picture Experts Group-4）视频编码器每个宏块在传送过程中Cache严重缺失，视频序列帧率低等问题，提出了运动估计算法的优化、Cache使用优化、SAD（Sum of Absolute Difference）和像素插值优化以及利用EDMA（Exte...针对MPEG-4（Moving Picture Experts Group-4）视频编码器每个宏块在传送过程中Cache严重缺失，视频序列帧率低等问题，提出了运动估计算法的优化、Cache使用优化、SAD（Sum of Absolute Difference）和像素插值优化以及利用EDMA（Extended Direct Memony Access）进行数据搬移等方法，提高存储速度，并在TMS320DM642 DSP（Digital Signal Processors）平台上实现了MPEG-4视频编码器的优化。实验结果表明，优化后比优化前，图像和视频处理函数的计算速度提高了1．18—97.5倍。视频序列帧率提高了6倍以上，达到了25帧／s的实时性要求。展开更多
基金supported by the National Key Research and Development Project(Grant No.2023YFB4705300)the National Natural Science Foundation of China(NSFC)(Grant Nos.62205200 and 62375168)the Natural Science Foundation of Shanghai(Grant No.22ZR1431600)。
文摘Highly programmable shape morphing of 4D-printed micro/nanostructures is urgently desired for applications in robotics and intelligent systems.However,due to the lack of autonomous holistic strategies throughout the target shape input,optimal material distribution generation,and fabrication program output,4D nanoprinting that permits arbitrary shape morphing remains a challenging task for manual design.In this study,we report an autonomous inverse encoding strategy to decipher the genetic code for material property distributions that can guide the encoded modeling toward arbitrarily pre-programmed 4D shape morphing.By tuning the laser power of each voxel at the nanoscale,the genetic code can be spatially programmed and controllable shape morphing can be realized through the inverse encoding process.Using this strategy,the 4D-printed structures can be designed and accurately shift to the target morphing of arbitrarily hand-drawn lines under stimulation.Furthermore,as a proof-of-concept,a flexible fiber micromanipulator that can approach the target region through pre-programmed shape morphing is autonomously inversely encoded according to the localized spatial environment.This strategy may contribute to the modeling and arbitrary shape morphing of micro/nanostructures fabricated via 4D nanoprinting,leading to cutting-edge applications in microfluidics,micro-robotics,minimally invasive robotic surgery,and tissue engineering.
文摘针对MPEG-4（Moving Picture Experts Group-4）视频编码器每个宏块在传送过程中Cache严重缺失，视频序列帧率低等问题，提出了运动估计算法的优化、Cache使用优化、SAD（Sum of Absolute Difference）和像素插值优化以及利用EDMA（Extended Direct Memony Access）进行数据搬移等方法，提高存储速度，并在TMS320DM642 DSP（Digital Signal Processors）平台上实现了MPEG-4视频编码器的优化。实验结果表明，优化后比优化前，图像和视频处理函数的计算速度提高了1．18—97.5倍。视频序列帧率提高了6倍以上，达到了25帧／s的实时性要求。
