SAR-BM3D is one of the state of the art despeckling algorithms for SAR images. However, when tackling with high resolution SAR images, it often has an unsatisfying despeckling performance in the homogeneous smooth reg...SAR-BM3D is one of the state of the art despeckling algorithms for SAR images. However, when tackling with high resolution SAR images, it often has an unsatisfying despeckling performance in the homogeneous smooth regions, together with a high time complexity. In this paper, a novel downsampled SAR-BM3D despeckling approach combined with edge compensation is proposed. The proposed algorithm consists of two steps. First, despeckle the image which is a downsampled version of original image with SAR-BM3D. Then, compensate edges in each level when upsampling. This approach not only utilizes the good ability of feature preservation, but also improves performance of smoothing homogenous regions. When it comes to high resolution SAR images, the efficiency can be raised by six to seven times, compared to original SAR-BM3D. Experiments on simulated and real SAR images show that the proposed method reaches a high level in terms of visual quality and act more efficiently.展开更多
By generating a high accuracy and high resolution geological model in Liuchu oil field, the technique of geological modeling is expanded and involved in primary geological study, making the sand bodies and reservoir b...By generating a high accuracy and high resolution geological model in Liuchu oil field, the technique of geological modeling is expanded and involved in primary geological study, making the sand bodies and reservoir be easily described in detail. The 3D visualization and 3D interactive editing of geological structure model are the key for modeling procedure. And a high accuracy and resolution geological model has been well applied in optimizing the production scheme.展开更多
High-resolution atomic-beam laser spectroscopy has been performed to study Stark effect of Ba atom. Stark spectra have been observed at various electric fields for Ba highly excited states. The scalar polarizability o...High-resolution atomic-beam laser spectroscopy has been performed to study Stark effect of Ba atom. Stark spectra have been observed at various electric fields for Ba highly excited states. The scalar polarizability of the transition from 6s5d3D2 to 5d6p3F3 at 728.0 nm and the tensor polarizability of the 3F3 level have been determined for the first time, to be αs = -89.8 (12) kHz/(kV/cm)2 and αt = -133.7 (20) kHz/(kV/cm)2, respectively.展开更多
The production capacity and efficiency for mechanized coal faces of large-scale mines depend on the detecting degree of mining structures. It is a major task for geological exploration in coal fields to detect minor s...The production capacity and efficiency for mechanized coal faces of large-scale mines depend on the detecting degree of mining structures. It is a major task for geological exploration in coal fields to detect minor structures in district. 3D high resolution seismic prospecting is a effective measure for solving this problem.展开更多
Silicone rubber(SR)is a versatile material widely used across various advanced functional applications,such as soft actuators and robots,flexible electronics,and medical devices.However,most SR molding methods rely on...Silicone rubber(SR)is a versatile material widely used across various advanced functional applications,such as soft actuators and robots,flexible electronics,and medical devices.However,most SR molding methods rely on traditional thermal processing or direct ink writing three-dimensional(3D)printing.These methods are not conducive to manufacturing complex structures and present challenges such as time inefficiency,poor accuracy,and the necessity of multiple steps,significantly limiting SR applications.In this study,we developed an SR-based ink suitable for vat photopolymerization 3D printing using a multi-thiol monomer.This ink enables the one-step fabrication of complex architectures with high printing resolution at the micrometer scale,providing excellent mechanical strength and superior chemical stability.Specifically,the optimized 3D printing SR-20 exhibits a tensile stress of 1.96 MPa,an elongation at break of 487.9%,and an elastic modulus of 225.4 kPa.Additionally,the 3D-printed SR samples can withstand various solvents(acetone,toluene,and tetrahydrofuran)and endure temperatures ranging from-50℃ to 180℃,demonstrating superior stability.As a emonstration of the application,we successfully fabricated a series of SR-based soft pneumatic actuators and grippers in a single step with this technology,allowing for free assembly for the first time.This ultraviolet-curable SR,with high printing resolution and exceptional stability performance,has significant potential to enhance the capabilities of 3D printing for applications in soft actuators,robotics,flexible electronics,and medical devices.展开更多
The time-interleaved analog-to-digital conversion(TIADC)technique is an effective method for increasing the sampling rate in a waveform digitization system.In this study,a 20-Gsps TIADC system was designed.A wide-band...The time-interleaved analog-to-digital conversion(TIADC)technique is an effective method for increasing the sampling rate in a waveform digitization system.In this study,a 20-Gsps TIADC system was designed.A wide-bandwidth performance was achieved by optimizing the analog circuits,and a sufficient effective number of bits(ENOB)performance guaranteed using the perfect reconstruction algorithm for mismatch error correction.The proposed system was verified by tests,and the results indicated that a-3 dB bandwidth of 6 GHz and the ENOB performance of 8.7 bits at 1 GHz and 7.6 bits at6 GHz were successfully achieved.展开更多
Current optical storage technologies utilizing phosphor media face challenges in achieving rapid and precise data recording with visible or infrared light,primarily due to the constraints of traditional charging techn...Current optical storage technologies utilizing phosphor media face challenges in achieving rapid and precise data recording with visible or infrared light,primarily due to the constraints of traditional charging techniques.Here,we introduce a cutting-edge method termed up-conversion charging(UCC)to address these challenges,enabling rapid and high-resolution data storage in phosphors.Our study focuses on the unique two-step ionization and non-linear charging characteristics of UCC in storage phosphors,specifically in a gallate composition Gd3Ga5O12:Cr3+.Remarkably,this technique enables data writing with high solution,requiring only 0.01 s of exposure per bit when utilizing a portable laser engraver equipped with visible-emitting diode lasers.The present strategy not only enhances recording efficiency but also ensures long-term data retention and superior rewritability.Moreover,we illustrate the versatility of UCC storage across various material systems through thermally-and optically-stimulated luminescence.Our outcomes highlight the transformative potential of the UCC method in advancing optical storage applications,offering significant improvements in the development of information storage solutions.展开更多
A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electro...A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electrons in a metal are resonated with photons.The structural parameters are fine-tuned and the sensing performance of the sensor is studied.The results show that the maximum spectral sensitivity reaches 18 000 nm/RIU in the refractive index range of 1.24—1.32,and the maximum resolution is 5.56×10^(-6) RIU.The novel structure with high sensitivity and low refractive index provides a new perspective for fluid density detection.展开更多
The seismic method is able to produce highly accurate images of the Earth's subsurface. Having such detail is not only an important factor in mining, but also in civil engineering. Bauxite exploration attracts bot...The seismic method is able to produce highly accurate images of the Earth's subsurface. Having such detail is not only an important factor in mining, but also in civil engineering. Bauxite exploration attracts both government and industrialists to invest in it because of the high percentage of aluminum present. The economic importance of extracting aluminum from bauxite encouraged us to take this challenge;to image bauxite layers by using a high-resolution seismic reflection method at Al Qassim, Saudi Arabia. Since the subsurface structure of the area is complex, this high-resolution reflection method was carried out along a 2D line with geophone and source interval, with settings at 5 m. The result for the seismic section shows that the depth and thickness of the bauxite layer varied from 20 to 34 m, and 3 to 7 m respectively. In addition, the bauxite layer was sandwiched between clay layers. In order to achieve an even more precise depth than presented by seismic section alone, we tied the drilled wells to the seismic data and we accomplished a well match with an approximation error of 1 - 2 m, which may have been caused by the upper clay layer or by very shallow loose subsurface material. The seismic method thus applied shows the ability to detect significant details within the near surface of the earth, and considers more cost-effective than only drilled wells.展开更多
Micro-LED is one of the most promising technologies for naked-eye 3D display.However,due to challenges related to efficiency,resolution,viewing range,and structure integration,the 3D micro-LED display is still at the ...Micro-LED is one of the most promising technologies for naked-eye 3D display.However,due to challenges related to efficiency,resolution,viewing range,and structure integration,the 3D micro-LED display is still at the conceptual stage.In this work,we introduce a double-functioned metalens composed of highly symmetric unit cells into the 3D micro-LED system.The nonpolarized spotlight generated by the micro-LED is collimated and deflected through the designed metalens.Inspired by the compound eyes,metalens modules with varying deflection angles are spliced and penetrated together,enabling a wide viewing angle without sacrificing resolution.Additionally,the viewing position can be dynamically adjusted using adjustable subpixels.The results demonstrate that the proposed metalens and its optical system can reach a viewing angle ranging from-41.5°to 41.5°and an adjustable optimum viewing distance from 25 to 75 cm.The deflection efficiency exceeds 80%,with a resolution of 910 PPI(pixels per inch).Our design shows great potential for naked-eye 3D display.展开更多
Fringe projection profilometry,a powerful technique for three-dimensional(3D)imaging and measurement,has been revolutionized by deep learning,achieving speeds of up to 100,000 frames per second(fps)while preserving hi...Fringe projection profilometry,a powerful technique for three-dimensional(3D)imaging and measurement,has been revolutionized by deep learning,achieving speeds of up to 100,000 frames per second(fps)while preserving highresolution.This advancement expands its applications to high-speed transient scenarios,opening new possibilities for ultrafast 3D measurements.展开更多
Traditional technologies for manufacturing microfluidic devices often involve the use of molds for polydimethylsiloxane(PDMS)casting generated from photolithography techniques,which are time-consuming,costly,and diffi...Traditional technologies for manufacturing microfluidic devices often involve the use of molds for polydimethylsiloxane(PDMS)casting generated from photolithography techniques,which are time-consuming,costly,and difficult to use in generating multilayered structure.As an alternative,3D printing allows rapid and cost-effective prototyping and customization of complex microfluidic structures.However,3Dprinted devices are typically opaque and are challenging to create small channels.Herein,we introduce a novel“programmable optical window bonding”3D printing method that incorporates the bonding of an optical window during the printing process,facilitating the fabrication of transparent microfluidic devices with high printing fidelity.Our approach allows direct and rapid manufacturing of complex microfluidic structure without the use of molds for PDMS casting.We successfully demonstrated the applications of this method by fabricating a variety of microfluidic devices,including perfusable chips for cell culture,droplet generators for spheroid formation,and high-resolution droplet microfluidic devices involving different channel width and height for rapid antibiotic susceptibility testing.Overall,our 3D printing method demonstrates a rapid and cost-effective approach for manufacturing microfluidic devices,particularly in the biomedical field,where rapid prototyping and high-quality optical analysis are crucial.展开更多
The distribution of gold in small acicular arsenopyrite of a pyrite-arsenopyrite association from Suzdal(Eastern Kazakhstan),Olympiada(Yenisei Ridge,Russia)and large pseudorhombic arsenopyrite crystals from Bazovskoe(...The distribution of gold in small acicular arsenopyrite of a pyrite-arsenopyrite association from Suzdal(Eastern Kazakhstan),Olympiada(Yenisei Ridge,Russia)and large pseudorhombic arsenopyrite crystals from Bazovskoe(Yakutia,Russia)orogenic-type deposits were investigated.On orogenic gold deposits in NE Asia,occurring mainly in black shales,two productive stages of ore deposition are distinguished,which correspond to two morphological varieties of arsenopyrite.At the early stage,fine-grained acicular-prismatic arsenopyrite with invisible gold was deposited;at the late stage,tabular arsenopyrite in association with free visible gold was formed.The samples of gold-bearing arsenopyrite were analyzed using Scanning Electron Microscopy,Electron Microprobe Analyses,Atomic Absorption and Laser Ablation Inductively Coupled Plasma Mass Spectrometry in combination with High Resolution 3D X-ray Computed Tomography(HRXCT).HRXCT does not destroy the studied mineral during the investigation.That technique permits to do an estimation of the amount of gold inclusions in minerals or host rocks and draw reasonable conclusions about the gold content of the ores,to study in detail the distribution patterns of metal inclusions(associated with certain minerals,cracks,crystal growth faces,etc.)and to determine the form of the gold.It can be used to understanding of the genesis of productive mineral associations,and to developing optimal technological schemes for gold extraction.展开更多
文摘SAR-BM3D is one of the state of the art despeckling algorithms for SAR images. However, when tackling with high resolution SAR images, it often has an unsatisfying despeckling performance in the homogeneous smooth regions, together with a high time complexity. In this paper, a novel downsampled SAR-BM3D despeckling approach combined with edge compensation is proposed. The proposed algorithm consists of two steps. First, despeckle the image which is a downsampled version of original image with SAR-BM3D. Then, compensate edges in each level when upsampling. This approach not only utilizes the good ability of feature preservation, but also improves performance of smoothing homogenous regions. When it comes to high resolution SAR images, the efficiency can be raised by six to seven times, compared to original SAR-BM3D. Experiments on simulated and real SAR images show that the proposed method reaches a high level in terms of visual quality and act more efficiently.
文摘By generating a high accuracy and high resolution geological model in Liuchu oil field, the technique of geological modeling is expanded and involved in primary geological study, making the sand bodies and reservoir be easily described in detail. The 3D visualization and 3D interactive editing of geological structure model are the key for modeling procedure. And a high accuracy and resolution geological model has been well applied in optimizing the production scheme.
文摘High-resolution atomic-beam laser spectroscopy has been performed to study Stark effect of Ba atom. Stark spectra have been observed at various electric fields for Ba highly excited states. The scalar polarizability of the transition from 6s5d3D2 to 5d6p3F3 at 728.0 nm and the tensor polarizability of the 3F3 level have been determined for the first time, to be αs = -89.8 (12) kHz/(kV/cm)2 and αt = -133.7 (20) kHz/(kV/cm)2, respectively.
文摘The production capacity and efficiency for mechanized coal faces of large-scale mines depend on the detecting degree of mining structures. It is a major task for geological exploration in coal fields to detect minor structures in district. 3D high resolution seismic prospecting is a effective measure for solving this problem.
基金supported by the Strategic Priority Program of the Chinese Academy of Sciences(XDB0470303)the National Key R&D Program of China(2022YFB4600102and 2023YFE0209900)+4 种基金the National Natural Science Foundation of China(52175201 and 51935012)the science and technology projects of Gansu province(22JR5RA093,24JRRA044,24YFFA014 and 24ZDGA014)the Innovation and Entrepreneurship Team Project of YEDA(2021TD007)the special supporting project for provincial leading talents of Yantaithe Taishan Scholars Program。
文摘Silicone rubber(SR)is a versatile material widely used across various advanced functional applications,such as soft actuators and robots,flexible electronics,and medical devices.However,most SR molding methods rely on traditional thermal processing or direct ink writing three-dimensional(3D)printing.These methods are not conducive to manufacturing complex structures and present challenges such as time inefficiency,poor accuracy,and the necessity of multiple steps,significantly limiting SR applications.In this study,we developed an SR-based ink suitable for vat photopolymerization 3D printing using a multi-thiol monomer.This ink enables the one-step fabrication of complex architectures with high printing resolution at the micrometer scale,providing excellent mechanical strength and superior chemical stability.Specifically,the optimized 3D printing SR-20 exhibits a tensile stress of 1.96 MPa,an elongation at break of 487.9%,and an elastic modulus of 225.4 kPa.Additionally,the 3D-printed SR samples can withstand various solvents(acetone,toluene,and tetrahydrofuran)and endure temperatures ranging from-50℃ to 180℃,demonstrating superior stability.As a emonstration of the application,we successfully fabricated a series of SR-based soft pneumatic actuators and grippers in a single step with this technology,allowing for free assembly for the first time.This ultraviolet-curable SR,with high printing resolution and exceptional stability performance,has significant potential to enhance the capabilities of 3D printing for applications in soft actuators,robotics,flexible electronics,and medical devices.
基金supported in part by the National Natural Science Foundation of China(No.11675173)the Youth Innovation Promotion Association CASthe CAS Center for Excellence in Particle Physics(CCEPP)。
文摘The time-interleaved analog-to-digital conversion(TIADC)technique is an effective method for increasing the sampling rate in a waveform digitization system.In this study,a 20-Gsps TIADC system was designed.A wide-bandwidth performance was achieved by optimizing the analog circuits,and a sufficient effective number of bits(ENOB)performance guaranteed using the perfect reconstruction algorithm for mismatch error correction.The proposed system was verified by tests,and the results indicated that a-3 dB bandwidth of 6 GHz and the ENOB performance of 8.7 bits at 1 GHz and 7.6 bits at6 GHz were successfully achieved.
基金supported by the National Natural Science Foundation of China(11774046,12074373,52072361,51732003,52172083)the Key Research and Department of Science and Technology of Jilin Province(20230101012JC).
文摘Current optical storage technologies utilizing phosphor media face challenges in achieving rapid and precise data recording with visible or infrared light,primarily due to the constraints of traditional charging techniques.Here,we introduce a cutting-edge method termed up-conversion charging(UCC)to address these challenges,enabling rapid and high-resolution data storage in phosphors.Our study focuses on the unique two-step ionization and non-linear charging characteristics of UCC in storage phosphors,specifically in a gallate composition Gd3Ga5O12:Cr3+.Remarkably,this technique enables data writing with high solution,requiring only 0.01 s of exposure per bit when utilizing a portable laser engraver equipped with visible-emitting diode lasers.The present strategy not only enhances recording efficiency but also ensures long-term data retention and superior rewritability.Moreover,we illustrate the versatility of UCC storage across various material systems through thermally-and optically-stimulated luminescence.Our outcomes highlight the transformative potential of the UCC method in advancing optical storage applications,offering significant improvements in the development of information storage solutions.
基金supported by the Natural Science Foundation of Tianjin City (No.19JCYBJC17000)the National Natural Science Foundation of China (No.11905159)。
文摘A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electrons in a metal are resonated with photons.The structural parameters are fine-tuned and the sensing performance of the sensor is studied.The results show that the maximum spectral sensitivity reaches 18 000 nm/RIU in the refractive index range of 1.24—1.32,and the maximum resolution is 5.56×10^(-6) RIU.The novel structure with high sensitivity and low refractive index provides a new perspective for fluid density detection.
文摘The seismic method is able to produce highly accurate images of the Earth's subsurface. Having such detail is not only an important factor in mining, but also in civil engineering. Bauxite exploration attracts both government and industrialists to invest in it because of the high percentage of aluminum present. The economic importance of extracting aluminum from bauxite encouraged us to take this challenge;to image bauxite layers by using a high-resolution seismic reflection method at Al Qassim, Saudi Arabia. Since the subsurface structure of the area is complex, this high-resolution reflection method was carried out along a 2D line with geophone and source interval, with settings at 5 m. The result for the seismic section shows that the depth and thickness of the bauxite layer varied from 20 to 34 m, and 3 to 7 m respectively. In addition, the bauxite layer was sandwiched between clay layers. In order to achieve an even more precise depth than presented by seismic section alone, we tied the drilled wells to the seismic data and we accomplished a well match with an approximation error of 1 - 2 m, which may have been caused by the upper clay layer or by very shallow loose subsurface material. The seismic method thus applied shows the ability to detect significant details within the near surface of the earth, and considers more cost-effective than only drilled wells.
基金supported by the National Natural Science Foundation of China(No.62104187)the State Key Lab of Digital Manufacturing Equipment&Technology of HUST(No.DMETKF2021014)。
文摘Micro-LED is one of the most promising technologies for naked-eye 3D display.However,due to challenges related to efficiency,resolution,viewing range,and structure integration,the 3D micro-LED display is still at the conceptual stage.In this work,we introduce a double-functioned metalens composed of highly symmetric unit cells into the 3D micro-LED system.The nonpolarized spotlight generated by the micro-LED is collimated and deflected through the designed metalens.Inspired by the compound eyes,metalens modules with varying deflection angles are spliced and penetrated together,enabling a wide viewing angle without sacrificing resolution.Additionally,the viewing position can be dynamically adjusted using adjustable subpixels.The results demonstrate that the proposed metalens and its optical system can reach a viewing angle ranging from-41.5°to 41.5°and an adjustable optimum viewing distance from 25 to 75 cm.The deflection efficiency exceeds 80%,with a resolution of 910 PPI(pixels per inch).Our design shows great potential for naked-eye 3D display.
文摘Fringe projection profilometry,a powerful technique for three-dimensional(3D)imaging and measurement,has been revolutionized by deep learning,achieving speeds of up to 100,000 frames per second(fps)while preserving highresolution.This advancement expands its applications to high-speed transient scenarios,opening new possibilities for ultrafast 3D measurements.
文摘Traditional technologies for manufacturing microfluidic devices often involve the use of molds for polydimethylsiloxane(PDMS)casting generated from photolithography techniques,which are time-consuming,costly,and difficult to use in generating multilayered structure.As an alternative,3D printing allows rapid and cost-effective prototyping and customization of complex microfluidic structures.However,3Dprinted devices are typically opaque and are challenging to create small channels.Herein,we introduce a novel“programmable optical window bonding”3D printing method that incorporates the bonding of an optical window during the printing process,facilitating the fabrication of transparent microfluidic devices with high printing fidelity.Our approach allows direct and rapid manufacturing of complex microfluidic structure without the use of molds for PDMS casting.We successfully demonstrated the applications of this method by fabricating a variety of microfluidic devices,including perfusable chips for cell culture,droplet generators for spheroid formation,and high-resolution droplet microfluidic devices involving different channel width and height for rapid antibiotic susceptibility testing.Overall,our 3D printing method demonstrates a rapid and cost-effective approach for manufacturing microfluidic devices,particularly in the biomedical field,where rapid prototyping and high-quality optical analysis are crucial.
基金financial support for the project by the Russian Federation represented by the Ministry of Education and Science of Russia(project number 13.1902.24.44,agreement number 075-15-2024-641).
文摘The distribution of gold in small acicular arsenopyrite of a pyrite-arsenopyrite association from Suzdal(Eastern Kazakhstan),Olympiada(Yenisei Ridge,Russia)and large pseudorhombic arsenopyrite crystals from Bazovskoe(Yakutia,Russia)orogenic-type deposits were investigated.On orogenic gold deposits in NE Asia,occurring mainly in black shales,two productive stages of ore deposition are distinguished,which correspond to two morphological varieties of arsenopyrite.At the early stage,fine-grained acicular-prismatic arsenopyrite with invisible gold was deposited;at the late stage,tabular arsenopyrite in association with free visible gold was formed.The samples of gold-bearing arsenopyrite were analyzed using Scanning Electron Microscopy,Electron Microprobe Analyses,Atomic Absorption and Laser Ablation Inductively Coupled Plasma Mass Spectrometry in combination with High Resolution 3D X-ray Computed Tomography(HRXCT).HRXCT does not destroy the studied mineral during the investigation.That technique permits to do an estimation of the amount of gold inclusions in minerals or host rocks and draw reasonable conclusions about the gold content of the ores,to study in detail the distribution patterns of metal inclusions(associated with certain minerals,cracks,crystal growth faces,etc.)and to determine the form of the gold.It can be used to understanding of the genesis of productive mineral associations,and to developing optimal technological schemes for gold extraction.
