Target micromotion not only plays an important role in target recognition but also leads to esoteric characteristics in synthetic aperture radar （SAR） imaging. This paper finds out an interesting phenomenon, i.e. th...Target micromotion not only plays an important role in target recognition but also leads to esoteric characteristics in synthetic aperture radar （SAR） imaging. This paper finds out an interesting phenomenon, i.e. the angular extent effect, in micro-motion target images formulated by the polar format algorithm. A micromotion target takes on multiple pairs of paired echoes （PEs） around the true point, and each PE extends for an angle which is exactly equal to the angular extent of the synthetic aperture, regardless of the micromotion frequency. The effect is derived and interpreted by using the characteristics of Bessel functions. Then it is demonstrated by simulation experiments of a target with different micromotion frequencies. The revelation and interpretation of the effect is highly beneficial to micromotion-target SAR image understanding as wel as target recognition.展开更多
提出并实现了一个本地轻量化课程教学智能辅助系统.该系统利用IPEX-LLM(Intel PyTorch extention for large language model)加速库,在计算资源受限的设备上高效部署并运行经过QLoRA(quantum-logic optimized resource allocation)框架...提出并实现了一个本地轻量化课程教学智能辅助系统.该系统利用IPEX-LLM(Intel PyTorch extention for large language model)加速库,在计算资源受限的设备上高效部署并运行经过QLoRA(quantum-logic optimized resource allocation)框架微调的大语言模型,并结合增强检索技术,实现了智能问答、智能出题、教学大纲生成、教学演示文档生成等4个主要功能模块的课程灵活定制,在帮助教师提高教学备课和授课的质量与效率、保护数据隐私的同时,支撑学生个性化学习并提供实时反馈.在性能实验中,以集成优化后的Chatglm3-6B模型为例,该系统处理64-token输出任务时仅需4.08 s,验证了其在资源受限环境下快速推理的能力.在实践案例分析中,通过与原生Chatgml-6B和ChatGPT4.0在功能实现上的对比,进一步表明了该系统具备优越的准确性和实用性.展开更多
The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating missiles.Traditional rotary motion deblurring methods suffer from ringing artifacts and noise,especially for l...The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating missiles.Traditional rotary motion deblurring methods suffer from ringing artifacts and noise,especially for large blur extents.To solve the above problems,we propose a progressive rotary motion deblurring framework consisting of a coarse deblurring stage and a refinement stage.In the first stage,we design an adaptive blur extents factor(BE factor)to balance noise suppression and details reconstruction.And a novel deconvolution model is proposed based on BE factor.In the second stage,a triplescale deformable module CNN(TDM-CNN)is designed to reduce the ringing artifacts,which can exploit the 2D information of an image and adaptively adjust spatial sampling locations.To establish a standard evaluation benchmark,a real-world rotary motion blur dataset is proposed and released,which includes rotary blurred images and corresponding ground truth images with different blur angles.Experimental results demonstrate that the proposed method outperforms the state-of-the-art models on synthetic and real-world rotary motion blur datasets.The code and dataset are available at https://github.com/JinhuiQin/RotaryDeblurring.展开更多
基金supported by the National Natural Science Foundationof China(6130214861101182)
文摘Target micromotion not only plays an important role in target recognition but also leads to esoteric characteristics in synthetic aperture radar （SAR） imaging. This paper finds out an interesting phenomenon, i.e. the angular extent effect, in micro-motion target images formulated by the polar format algorithm. A micromotion target takes on multiple pairs of paired echoes （PEs） around the true point, and each PE extends for an angle which is exactly equal to the angular extent of the synthetic aperture, regardless of the micromotion frequency. The effect is derived and interpreted by using the characteristics of Bessel functions. Then it is demonstrated by simulation experiments of a target with different micromotion frequencies. The revelation and interpretation of the effect is highly beneficial to micromotion-target SAR image understanding as wel as target recognition.
文摘随着全球气候变暖加剧,北极地区的大气海洋环境剧烈变化,导致海冰变化更加不稳定,使得海冰预测的难度增大。本研究选择海表温度、2 m平均气温、二氧化碳浓度为大气海洋变量,海冰范围距平为时序特征参数,将上述参量作为北极海冰范围(Sea Ice Extent,SIE)的预测要素,建立了面向SIE的多变量长短期记忆(Long Short Term Memory,LSTM)神经网络模型,对比分析了2015-2021年不同时间序列预测模型的预测结果。结果显示:本研究所构建模型的RMSE、MAE、MAPE分别为0.353×106 km2、0.261×106 km2和3.191%。相比于其他预测模型,结合大气海洋变量和时序特征参数后的LSTM模型预测结果误差更小,拟合效果更好,可以消除夏季海冰剧烈变化对预测效果的影响,提高海冰范围的预测精度,对北极航道的通航安全保障工作具有重要的研究与应用价值。
文摘提出并实现了一个本地轻量化课程教学智能辅助系统.该系统利用IPEX-LLM(Intel PyTorch extention for large language model)加速库,在计算资源受限的设备上高效部署并运行经过QLoRA(quantum-logic optimized resource allocation)框架微调的大语言模型,并结合增强检索技术,实现了智能问答、智能出题、教学大纲生成、教学演示文档生成等4个主要功能模块的课程灵活定制,在帮助教师提高教学备课和授课的质量与效率、保护数据隐私的同时,支撑学生个性化学习并提供实时反馈.在性能实验中,以集成优化后的Chatglm3-6B模型为例,该系统处理64-token输出任务时仅需4.08 s,验证了其在资源受限环境下快速推理的能力.在实践案例分析中,通过与原生Chatgml-6B和ChatGPT4.0在功能实现上的对比,进一步表明了该系统具备优越的准确性和实用性.
基金the National Natural Science Foundation of China under Grant 62075169,Grant 62003247,and Grant 62061160370the Hubei Province Key Research and Development Program under Grant 2021BBA235the Zhuhai Basic and Applied Basic Research Foundation under Grant ZH22017003200010PWC.
文摘The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating missiles.Traditional rotary motion deblurring methods suffer from ringing artifacts and noise,especially for large blur extents.To solve the above problems,we propose a progressive rotary motion deblurring framework consisting of a coarse deblurring stage and a refinement stage.In the first stage,we design an adaptive blur extents factor(BE factor)to balance noise suppression and details reconstruction.And a novel deconvolution model is proposed based on BE factor.In the second stage,a triplescale deformable module CNN(TDM-CNN)is designed to reduce the ringing artifacts,which can exploit the 2D information of an image and adaptively adjust spatial sampling locations.To establish a standard evaluation benchmark,a real-world rotary motion blur dataset is proposed and released,which includes rotary blurred images and corresponding ground truth images with different blur angles.Experimental results demonstrate that the proposed method outperforms the state-of-the-art models on synthetic and real-world rotary motion blur datasets.The code and dataset are available at https://github.com/JinhuiQin/RotaryDeblurring.
