In a single-pixel fast imaging setup,the data collected by the single-pixel detector needs to be processed by a computer,but the speed of the latter will affect the image reconstruction time.Here we propose two kinds ...In a single-pixel fast imaging setup,the data collected by the single-pixel detector needs to be processed by a computer,but the speed of the latter will affect the image reconstruction time.Here we propose two kinds of setups which are able to transform non-visible into visible light imaging,wherein their computing process is replaced by a camera integration mode.The image captured by the camera has a low contrast,so here we present an algorithm that can realize a high quality image in near-infrared to visible cross-waveband imaging.The scheme is verified both by simulation and in actual experiments.The setups demonstrate the great potential for single-pixel imaging and high-speed cross-waveband imaging for future practical applications.展开更多
光谱成像系统受色差影响会导致图谱混叠,本文将单像素成像以及计算关联成像分别与光谱成像系统相结合,并在系统中引入900~1700 nm适用的消色差透镜来校正色差。首先计算出不同胶合消色差透镜的色差大小并以此选取透镜,所选消色差透镜相...光谱成像系统受色差影响会导致图谱混叠,本文将单像素成像以及计算关联成像分别与光谱成像系统相结合,并在系统中引入900~1700 nm适用的消色差透镜来校正色差。首先计算出不同胶合消色差透镜的色差大小并以此选取透镜,所选消色差透镜相较其它透镜对色差校正可以提高一个量级。其次分析了色差对光谱成像系统的影响以及单像素成像和计算关联成像的差异。最后仿真和试验分析单像素光谱成像和计算关联光谱成像特点。试验结果表明对于900~1700 nm的近红外光谱成像,基于消色差透镜的单像素光谱成像系统取得了更好的图像重构结果,其峰值信噪比(Peak Signal to Noise Ratio,PSNR)提高了3.93 dB,结构相似度(Structural Similarity,SSIM)提高了0.96%。消色差透镜的单像素光谱成像系统在近红外光谱成像中重构图像效果优于无消色差透镜的计算关联光谱成像。展开更多
The control strategy is presented using passive and active hybrid magnetically suspended flywheels（P＆A MSFWs）,which can help meet the requirements of high precision and high stability for earth-observation satellit...The control strategy is presented using passive and active hybrid magnetically suspended flywheels（P＆A MSFWs）,which can help meet the requirements of high precision and high stability for earth-observation satellites.Compared with the conventional flywheel,P＆A MSFW has more rotation degrees of freedom（DOFs）since the rotor is suspended by magnetic bearings,and thus requires more efficient controllers.A modified sliding mode control law（SMC）to our novel nonlinear and coupled system is presented,which is interrupted by inertia matrix uncertainties and external disturbances.SMC law via Lyapunov method is improved,and a fuzzy control scheme is used to attenuate the chatting and control attitude accuracy and maintain the robustness of SMC.Simulation results are provided to illustrate the efficiency of our model by using our control law.展开更多
文摘In a single-pixel fast imaging setup,the data collected by the single-pixel detector needs to be processed by a computer,but the speed of the latter will affect the image reconstruction time.Here we propose two kinds of setups which are able to transform non-visible into visible light imaging,wherein their computing process is replaced by a camera integration mode.The image captured by the camera has a low contrast,so here we present an algorithm that can realize a high quality image in near-infrared to visible cross-waveband imaging.The scheme is verified both by simulation and in actual experiments.The setups demonstrate the great potential for single-pixel imaging and high-speed cross-waveband imaging for future practical applications.
文摘光谱成像系统受色差影响会导致图谱混叠,本文将单像素成像以及计算关联成像分别与光谱成像系统相结合,并在系统中引入900~1700 nm适用的消色差透镜来校正色差。首先计算出不同胶合消色差透镜的色差大小并以此选取透镜,所选消色差透镜相较其它透镜对色差校正可以提高一个量级。其次分析了色差对光谱成像系统的影响以及单像素成像和计算关联成像的差异。最后仿真和试验分析单像素光谱成像和计算关联光谱成像特点。试验结果表明对于900~1700 nm的近红外光谱成像,基于消色差透镜的单像素光谱成像系统取得了更好的图像重构结果,其峰值信噪比(Peak Signal to Noise Ratio,PSNR)提高了3.93 dB,结构相似度(Structural Similarity,SSIM)提高了0.96%。消色差透镜的单像素光谱成像系统在近红外光谱成像中重构图像效果优于无消色差透镜的计算关联光谱成像。
文摘The control strategy is presented using passive and active hybrid magnetically suspended flywheels（P＆A MSFWs）,which can help meet the requirements of high precision and high stability for earth-observation satellites.Compared with the conventional flywheel,P＆A MSFW has more rotation degrees of freedom（DOFs）since the rotor is suspended by magnetic bearings,and thus requires more efficient controllers.A modified sliding mode control law（SMC）to our novel nonlinear and coupled system is presented,which is interrupted by inertia matrix uncertainties and external disturbances.SMC law via Lyapunov method is improved,and a fuzzy control scheme is used to attenuate the chatting and control attitude accuracy and maintain the robustness of SMC.Simulation results are provided to illustrate the efficiency of our model by using our control law.
