Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution...Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution sparse compound-eye camera(CEC)based on dual-end collaborative optimization is proposed,which provides a cost-effective way to break through the trade-off among the field of view,resolution,and imaging speed.In the optical end,a sparse CEC based on liquid lenses is designed,which can realize large-field-of-view imaging in real time,and fast zooming within 5 ms.In the computational end,a disturbed degradation model driven super-resolution network(DDMDSR-Net)is proposed to deal with complex image degradation issues in actual imaging situations,achieving high-robustness and high-fidelity resolution enhancement.Based on the proposed dual-end collaborative optimization framework,the angular resolution of the CEC can be enhanced from 71.6"to 26.0",which provides a solution to realize high-resolution imaging for array camera dispensing with high optical hardware complexity and data transmission bandwidth.Experiments verify the advantages of the CEC based on dual-end collaborative optimization in high-fidelity reconstruction of real scene images,kilometer-level long-distance detection,and dynamic imaging and precise recognition of targets of interest.展开更多
An all-silicone zoom lens is fabricated. A tunable metal ringer is fettered around the side edge of the lens. A nylon rope linking a motor is tied, encircling the notch in the metal ringer. While the motor is operatin...An all-silicone zoom lens is fabricated. A tunable metal ringer is fettered around the side edge of the lens. A nylon rope linking a motor is tied, encircling the notch in the metal ringer. While the motor is operating, the rope can shrink or release to change the focal length of the lens. A calculation method is developed to obtain the focal length and the zoom ratio. The testing is carried out in succession. The testing values are compared with the calculated ones, and they tally with each other well. Finally, the imaging performance of the all-silicone lens is demonstrated. The all-silicone lens has potential uses in cellphone cameras, notebook cameras, micro monitor lenses, etc.展开更多
A novel inverted telephoto four mirror zoom system with large field of view （FOV） was designed over a wide specWal bandwidth. The initial configuration of the zoom system was obtained by applying the aberration equa...A novel inverted telephoto four mirror zoom system with large field of view （FOV） was designed over a wide specWal bandwidth. The initial configuration of the zoom system was obtained by applying the aberration equations under certain constraints. Then, a method was presented to correlate the aspheric coefficients with the aberrations of this system. By using this method, the required image quality could be achieved after optimiza- tion using the ZEMAX Optical Design Code. Besides good image quality, another benefits of using this system is the potential for using cheap optics.展开更多
江西南昌西汉海昏侯墓是近年来汉代考古的重要发现,其出土的大量珍贵文物为研究西汉列侯葬制、复原汉代社会生活提供了难能可贵的实物资料。其中墓园M1和M5棺内各出土了玻璃席,作为玉敛葬中的一种葬具,是西汉手工业水平的重要见证,也是...江西南昌西汉海昏侯墓是近年来汉代考古的重要发现,其出土的大量珍贵文物为研究西汉列侯葬制、复原汉代社会生活提供了难能可贵的实物资料。其中墓园M1和M5棺内各出土了玻璃席,作为玉敛葬中的一种葬具,是西汉手工业水平的重要见证,也是列侯丧葬等级和汉代法赙制度的具体表征。本研究使用傅里叶变换显微红外光谱(micro-FTIR)、热裂解气相色谱-质谱分析(Py-GC/MS)以及基于质谱的动物考古学技术(zooarchaeology by mass spectrometry,ZooMS)等多种手段,对海昏侯墓出土玻璃席包边及疑似胶结材料进行了科学分析。首先利用傅里叶变换显微红外光谱确定样品中均含有蛋白质成分,再利用热裂解气相色谱质谱技术检测包边残留物和疑似胶结材料的主要成分,判断包边样品应为动物性来源,最后使用基于质谱的动物考古学技术,确定了M1刘贺墓玻璃席包边残留物的生物来源为普通牛,推测包边残留物材料为牛皮。包边样品中检测到的少量酚类物质,表明牛皮在鞣制过程中可能使用了植物鞣剂。样品中含量较高的脂肪酸类物质可能来源于皮革鞣制中的加脂处理。此外,两件胶结材料样品中含有吲哚类、脯氨酸类化合物以及磷酸三甲脂,但未发现胆固醇类化合物,判断胶结材料应为蛋清。本研究明确了玻璃席包边制作材料,为了解古代制席工艺、制作技法提供了科学认知,两张玻璃席制作精美、工艺复杂,展现了西汉中期高超的制席工艺,为后续针对玻璃席开展的保护修复工作提供了重要参考依据。展开更多
To address the limitations of existing coupling methods in aero-engine system simulation,which fail to adaptively adjust iterative parameters and coupling relationships,which can result in low efficiency and in⁃stabil...To address the limitations of existing coupling methods in aero-engine system simulation,which fail to adaptively adjust iterative parameters and coupling relationships,which can result in low efficiency and in⁃stability,this study introduces a‘Dynamic Event-Driven Co-Simulation’algorithm integrated with decision tree algorithms.This algorithm separates the overall coupling relationships and the main solver from the primary mod⁃el,utilizing a dynamic event monitoring module to adaptively adjust simulation strategies,including iteration pa⁃rameters,coupling relationships,and convergence criteria.This facilitates efficient adaptive simulations of dy⁃namic events while balancing solution accuracy and computational efficiency.The research focuses on a twinshaft turbofan engine,establishing six system-level models that encompass overall performance and various sub⁃systems based on three coupling methods,along with a multidisciplinary multi-fidelity simulation framework in⁃corporating a 3D CFD nozzle model.The study tests both model exchange and coupled simulation methods under a 14 s transient acceleration and deceleration scenario.In a 100%throttle condition,a high-fidelity nozzle model is used to analyze the sensitivity of different convergence criteria on computational efficiency and accuracy.Re⁃sults indicate that the accuracy and efficiency achieved with this method are comparable to those of PROOSIS soft⁃ware(18 s and 35 s,respectively),while being 71%more efficient than Simulink software(62 s and 120 s,re⁃spectively).Furthermore,appropriately relaxing the convergence criteria for the 0D model(from 10-6 to 10-4)while enhancing those for the 3D model(from 3000 steps to 6000 steps)can effectively balance computational accuracy and efficiency.展开更多
基金financial supports from National Natural Science Foundation of China(Grant Nos.U23A20368 and 62175006)Academic Excellence Foundation of BUAA for PhD Students.
文摘Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution sparse compound-eye camera(CEC)based on dual-end collaborative optimization is proposed,which provides a cost-effective way to break through the trade-off among the field of view,resolution,and imaging speed.In the optical end,a sparse CEC based on liquid lenses is designed,which can realize large-field-of-view imaging in real time,and fast zooming within 5 ms.In the computational end,a disturbed degradation model driven super-resolution network(DDMDSR-Net)is proposed to deal with complex image degradation issues in actual imaging situations,achieving high-robustness and high-fidelity resolution enhancement.Based on the proposed dual-end collaborative optimization framework,the angular resolution of the CEC can be enhanced from 71.6"to 26.0",which provides a solution to realize high-resolution imaging for array camera dispensing with high optical hardware complexity and data transmission bandwidth.Experiments verify the advantages of the CEC based on dual-end collaborative optimization in high-fidelity reconstruction of real scene images,kilometer-level long-distance detection,and dynamic imaging and precise recognition of targets of interest.
基金supported by the Foundation of Science & Technology Department of Henan Province, China (Grant No. 102102210477)the Foundation of Science & Technology Bureau of Luoyang City, China (Grant No. 1101040A)
文摘An all-silicone zoom lens is fabricated. A tunable metal ringer is fettered around the side edge of the lens. A nylon rope linking a motor is tied, encircling the notch in the metal ringer. While the motor is operating, the rope can shrink or release to change the focal length of the lens. A calculation method is developed to obtain the focal length and the zoom ratio. The testing is carried out in succession. The testing values are compared with the calculated ones, and they tally with each other well. Finally, the imaging performance of the all-silicone lens is demonstrated. The all-silicone lens has potential uses in cellphone cameras, notebook cameras, micro monitor lenses, etc.
文摘A novel inverted telephoto four mirror zoom system with large field of view （FOV） was designed over a wide specWal bandwidth. The initial configuration of the zoom system was obtained by applying the aberration equations under certain constraints. Then, a method was presented to correlate the aspheric coefficients with the aberrations of this system. By using this method, the required image quality could be achieved after optimiza- tion using the ZEMAX Optical Design Code. Besides good image quality, another benefits of using this system is the potential for using cheap optics.
文摘江西南昌西汉海昏侯墓是近年来汉代考古的重要发现,其出土的大量珍贵文物为研究西汉列侯葬制、复原汉代社会生活提供了难能可贵的实物资料。其中墓园M1和M5棺内各出土了玻璃席,作为玉敛葬中的一种葬具,是西汉手工业水平的重要见证,也是列侯丧葬等级和汉代法赙制度的具体表征。本研究使用傅里叶变换显微红外光谱(micro-FTIR)、热裂解气相色谱-质谱分析(Py-GC/MS)以及基于质谱的动物考古学技术(zooarchaeology by mass spectrometry,ZooMS)等多种手段,对海昏侯墓出土玻璃席包边及疑似胶结材料进行了科学分析。首先利用傅里叶变换显微红外光谱确定样品中均含有蛋白质成分,再利用热裂解气相色谱质谱技术检测包边残留物和疑似胶结材料的主要成分,判断包边样品应为动物性来源,最后使用基于质谱的动物考古学技术,确定了M1刘贺墓玻璃席包边残留物的生物来源为普通牛,推测包边残留物材料为牛皮。包边样品中检测到的少量酚类物质,表明牛皮在鞣制过程中可能使用了植物鞣剂。样品中含量较高的脂肪酸类物质可能来源于皮革鞣制中的加脂处理。此外,两件胶结材料样品中含有吲哚类、脯氨酸类化合物以及磷酸三甲脂,但未发现胆固醇类化合物,判断胶结材料应为蛋清。本研究明确了玻璃席包边制作材料,为了解古代制席工艺、制作技法提供了科学认知,两张玻璃席制作精美、工艺复杂,展现了西汉中期高超的制席工艺,为后续针对玻璃席开展的保护修复工作提供了重要参考依据。
文摘To address the limitations of existing coupling methods in aero-engine system simulation,which fail to adaptively adjust iterative parameters and coupling relationships,which can result in low efficiency and in⁃stability,this study introduces a‘Dynamic Event-Driven Co-Simulation’algorithm integrated with decision tree algorithms.This algorithm separates the overall coupling relationships and the main solver from the primary mod⁃el,utilizing a dynamic event monitoring module to adaptively adjust simulation strategies,including iteration pa⁃rameters,coupling relationships,and convergence criteria.This facilitates efficient adaptive simulations of dy⁃namic events while balancing solution accuracy and computational efficiency.The research focuses on a twinshaft turbofan engine,establishing six system-level models that encompass overall performance and various sub⁃systems based on three coupling methods,along with a multidisciplinary multi-fidelity simulation framework in⁃corporating a 3D CFD nozzle model.The study tests both model exchange and coupled simulation methods under a 14 s transient acceleration and deceleration scenario.In a 100%throttle condition,a high-fidelity nozzle model is used to analyze the sensitivity of different convergence criteria on computational efficiency and accuracy.Re⁃sults indicate that the accuracy and efficiency achieved with this method are comparable to those of PROOSIS soft⁃ware(18 s and 35 s,respectively),while being 71%more efficient than Simulink software(62 s and 120 s,re⁃spectively).Furthermore,appropriately relaxing the convergence criteria for the 0D model(from 10-6 to 10-4)while enhancing those for the 3D model(from 3000 steps to 6000 steps)can effectively balance computational accuracy and efficiency.
