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Fast-zoom and high-resolution sparse compound-eye camera based on dual-end collaborative optimization 被引量:1
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作者 Yi Zheng Hao-Ran Zhang +5 位作者 Xiao-Wei Li You-Ran Zhao Zhao-Song Li Ye-Hao Hou Chao Liu Qiong-Hua Wang 《Opto-Electronic Advances》 2025年第6期4-15,共12页
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
关键词 compound-eye camera ZOOM high resolution collaborative optimization
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A high-resolution lithospheric magnetic field model of China and surroundings by using CHAMP,Swarm,CSES-1,and MSS-1 satellite magnetic measurements and aeromagnetic anomaly data 被引量:1
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作者 Pan Zhang JinSong Du +5 位作者 Liang Yin Qing Yan JiaXuan Zhang HouPu Li Keke Zhang Chao Chen 《Earth and Planetary Physics》 2025年第3期686-696,共11页
The CUG_CLMFM3D series comprises high-resolution three-dimensional lithospheric magnetic field models for China and its surroundings.The first version,CUG_CLMFM3Dv1,is a spherical cap harmonic model integrating the WD... The CUG_CLMFM3D series comprises high-resolution three-dimensional lithospheric magnetic field models for China and its surroundings.The first version,CUG_CLMFM3Dv1,is a spherical cap harmonic model integrating the WDMAMv2(World Digital Magnetic Anomaly Map version 2)global magnetic anomaly grid and nearly a decade of CHAMP(Challenging Minisatellite Payload for Geophysical Research and Application)satellite vector data.It achieves a~5.7 km resolution but has limitations:the WDMAMv2 grid lacks high-resolution data in the southern Xinjiang and Tibet regions,which leads to missing small-to medium-scale anomalies,and unfiltered CHAMP data introduce low-frequency conflicts with global spherical harmonic models.Above the altitude of 150 km,correlations with global models drop below 0.9.The second version,CUG_CLMFM3Dv2,addresses these issues by incorporating 5-km-resolution aeromagnetic data and rigorously processed satellite data from CHAMP,Swarm,CSES-1(China Seismo-Electromagnetic Satellite 1),and MSS-1(Macao Science Satellite 1).The comparison analysis shows that the CUG_CLMFM3Dv2 captures finer high-frequency details and more stable long-wavelength signals,offering improved magnetic anomaly maps for further geological and geophysical studies. 展开更多
关键词 Macao Science Satellite 1 China Seismo-Electromagnetic Satellite 1 revised spherical cap harmonic analysis high resolution lithospheric magnetic field China and surroundings
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High-resolution neutron spectrum regulation for promoting transuranic isotope production
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作者 Qing-Quan Pan Lian-Jie Wang +2 位作者 Bang-Yang Xia Yun Cai Xiao-Jing Liu 《Nuclear Science and Techniques》 2025年第9期236-247,共12页
A method is proposed for high-resolution neutron spectrum regulation across the entire energy domain.It was applied to in-reactor transuranic isotope production.This method comprises four modules:a neutron spectrum pe... A method is proposed for high-resolution neutron spectrum regulation across the entire energy domain.It was applied to in-reactor transuranic isotope production.This method comprises four modules:a neutron spectrum perturbation module,a neutron spectrum calculation module,a neutron spectrum valuation module,and an intelligent optimization module.It makes it possible to determine the optimal neutron spectrum for transuranic isotope production and a regulation scheme to establish this neutron spectrum within the reactor.The state-of-the-art production schemes for^(252)Cf and^(238)Pu in the High Flux Isotope Reactor were optimized,improving the yield of^(252)Cf by 12.16%and that of^(238)Pu by 7.53-25.84%.Moreover,the proposed optimization schemes only disperse certain nuclides into the targets without modifying the reactor design parameters,making them simple and feasible.The new method achieves efficient and precise neutron spectrum optimization,maximizing the production of transuranic isotopes. 展开更多
关键词 Californium-252 Plutonium-238 Neutron spectrum regulation Genetic algorithm high resolution
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Design, Performance, and Applications of AMMIS: A Novel Airborne Multimodular Imaging Spectrometer for High-Resolution Earth Observations
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作者 Jianxin Jia Yueming Wang +15 位作者 Xiaorou Zheng Liyin Yuan Chunlai Li Yi Cen Fuqi Si Gang Lv Chongru Wang Shengwei Wang Changxing Zhang Dong Zhang Daogang He Xiaoqiong Zhuang Guicheng Han Mingyang Zhang Juha Hyyppa Jianyu Wang 《Engineering》 2025年第4期38-56,共19页
Airborne hyperspectral imaging spectrometers have been used for Earth observation over the past four decades.Despite the high sensitivity of push-broom hyperspectral imagers,they experience limited swath and wavelengt... Airborne hyperspectral imaging spectrometers have been used for Earth observation over the past four decades.Despite the high sensitivity of push-broom hyperspectral imagers,they experience limited swath and wavelength coverage.In this study,we report the development of a push-broom airborne multimodular imaging spectrometer(AMMIS)that spans ultraviolet(UV),visible near-infrared(VNIR),shortwave infrared(SWIR),and thermal infrared(TIR)wavelengths.As an integral part of China's HighResolution Earth Observation Program,AMMIS is intended for civilian applications and for validating key technologies for future spaceborne hyperspectral payloads.It has been mounted on aircraft platforms such as Y-5,Y-12,and XZ-60.Since 2016,AMMIS has been used to perform more than 30 flight campaigns and gather more than 200 TB of hyperspectral data.This study describes the system design,calibration techniques,performance tests,flight campaigns,and applications of the AMMIS.The system integrates UV,VNIR,SWIR,and TIR modules,which can be operated in combination or individually based on the application requirements.Each module includes three spectrometers,utilizing field-of-view(FOV)stitching technology to achieve a 40°FOV,thereby enhancing operational efficiency.We designed advanced optical systems for all modules,particularly for the TIR module,and employed cryogenic optical technology to maintain optical system stability at 100 K.Both laboratory and in-flight calibrations were conducted to improve preprocessing accuracy and produce high-quality hyperspectral data.The AMMIS features more than 1400 spectral bands,with spectral sampling intervals of 0.1 nm for UV,2.4 nm for VNIR,3 nm for SWIR,and 32 nm for TIR.In addition,the instantaneous fields of view(IFoVs)for the four modules were 0.5,0.25,0.5,and 1 mrad,respectively,with the VNIR module achieving an IFoV of 0.125 mrad in the high-spatial-resolution mode.This study reports on land-cover surveys,pollution gas detection,mineral exploration,coastal water detection,and plant investigations conducted using AMMIS,highlighting its excellent performance.Furthermore,we present three hyperspectral datasets with diverse scene distributions and categories suitable for developing artificial intelligence algorithms.This study paves the way for next-generation airborne and spaceborne hyperspectral payloads and serves as a valuable reference for hyperspectral sensor designers and data users. 展开更多
关键词 Artificial intelligence Push-broom hyperspectral imager high spatial resolution Cryogenic optical technology Earth observations
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The Real⁃time and High⁃resolution Interactive Digital Human
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作者 Haiquan Fang Dian Yu 《Journal of Harbin Institute of Technology(New Series)》 2025年第5期41-51,共11页
Synthesizing a real⁃time,high⁃resolution,and lip⁃sync digital human is a challenging task.Although the Wav2Lip model represents a remarkable advancement in real⁃time lip⁃sync,its clarity is still limited.To address th... Synthesizing a real⁃time,high⁃resolution,and lip⁃sync digital human is a challenging task.Although the Wav2Lip model represents a remarkable advancement in real⁃time lip⁃sync,its clarity is still limited.To address this,we enhanced the Wav2Lip model in this study and trained it on a high⁃resolution video dataset produced in our laboratory.Experimental results indicate that the improved Wav2Lip model produces digital humans with greater clarity than the original model,while maintaining its real⁃time performance and accurate lip⁃sync.We implemented the improved Wav2Lip model in a government interface application,generating a government digital human.Testing revealed that this government digital human can interact seamlessly with users in real⁃time,delivering clear visuals and synthesized speech that closely resembles a human voice. 展开更多
关键词 digital human lip⁃sync highresolution video generation talking face generation
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Mid-Infrared High-Resolution Achromatic Air Microlens in Silicon
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作者 Haoran Mo Zitao Ji +3 位作者 Yidong Zheng Huakang Yu Wenyao Liang Zhi-Yuan Li 《Chinese Physics Letters》 2025年第5期62-68,共7页
Infrared(IR) optics have garnered significant attention due to growing demands in advanced optical imaging,communication, detection, and sensing. Among various IR devices, microlenses and microlens arrays offer distin... Infrared(IR) optics have garnered significant attention due to growing demands in advanced optical imaging,communication, detection, and sensing. Among various IR devices, microlenses and microlens arrays offer distinct advantages in integration capability, imaging precision, multifunctionality, and cost-effective manufacturing. We present a novel design of high-resolution achromatic microlens in the mid-IR region. Different from traditional high-refractive-index convex microlenses embedded within a low-index background medium, the current design is a low-index air concave microlens embedded within a high-index silicon medium. The designed air microlens exhibits capabilities in high-resolution imaging(~λ/6) and achromatic performance across the 3–5 μm mid-IR spectrum. The air microlens could be assembled in large-area microlens arrays or as part of multi-lens system.When combined with the HgCdTe detector system placed on the focal plane, the air microlens can find promising applications in high-resolution optical imaging and high-sensitivity photoelectric detection. 展开更多
关键词 ir devices optical imaging microlens arrays mid infrared advanced optical imagingcommunication high resolution air microlens silicon
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High-temporal-resolution ERT characterization for vegetation effects on soil hydrological response under wet-dry cycles
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作者 Wei Yan Weiming Xu +2 位作者 Taosheng Huang Ping Shen Wan-Huan Zhou 《Biogeotechnics》 2025年第2期13-20,共8页
Characterization of vegetation effect on soil response is essential for comprehending site-specific hydrological processes.Traditional research often relies on sensors or remote sensing data to examine the hydrologica... Characterization of vegetation effect on soil response is essential for comprehending site-specific hydrological processes.Traditional research often relies on sensors or remote sensing data to examine the hydrological properties of vegetation zones,yet these methods are limited by either measurement sparsity or spatial inaccuracy.Therefore,this paper is the first to propose a data-driven approach that incorporates high-temporal-resolution electrical resistivity tomography(ERT)to quantify soil hydrological response.Time-lapse ERT is deployed on a vegetated slope site in Foshan,China,during a discontinuous rainfall induced by Typhoon Haikui.A total of 97 ERT measurements were collected with an average time interval of 2.7 hours.The Gaussian Mixture Model(GMM)is applied to quantify the level of response and objectively classify impact zones based on features extracted directly from the ERT data.The resistivity-moisture content correlation is established based on on-site sensor data to characterize infiltration and evapotranspiration across wet-dry conditions.The findings are compared with the Normalized Difference Vegetation Index(NDVI),a common indicator for vegetation quantification,to reveal potential spatial errors in remote sensing data.In addition,this study provides discussions on the potential applications and future directions.This paper showcases significant spatio-temporal advantages over existing studies,providing a more detailed and accurate characterization of superficial soil hydrological response. 展开更多
关键词 VEGETATION high temporal resolution Electrical resistivity tomography Soil hydrological response Gaussian mixture model
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Precision Microenvironment-Driven Isothermal Annealing for the Self-Assembly of Perpendicular Block Copolymers in High-Resolution Lithography Applications
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作者 Xiaotong Zhao Yuanlang Hou +11 位作者 Hanxiao Lu Sisi Chen Hui Bai Hanzhe Miao Yuanyuan Guan Sibo Fu Meng Su Xiangshun Geng Ming Lei Yi Yang Yanlin Song Tian-Ling Ren 《Chinese Physics Letters》 2025年第11期375-382,共8页
Block copolymer(BCP) nanolithography offers potential beyond traditional photolithographic limits, yet reliably producing low-defect, perpendicular domains remains challenging. We introduce a microenvironmentdriven is... Block copolymer(BCP) nanolithography offers potential beyond traditional photolithographic limits, yet reliably producing low-defect, perpendicular domains remains challenging. We introduce a microenvironmentdriven isothermal annealing method for directed self-assembly of BCP thin films. By annealing films at stable temperature in a quasi-sealed, inert-gas chamber, our approach promotes highly uniform perpendicular lamellar nanopatterns over large areas, effectively mitigating environmental fluctuations and emulating solvent-vapor annealing without solvent exposure. Resulting BCP structures demonstrate enhanced spatial coherence and notably low defect density. Furthermore, we successfully transfer these nanopatterns into precise metal nano-line arrays,confirming the method's capability for high-fidelity pattern replication. This scalable, solvent-free technique provides a robust, reliable route for high-resolution nanopatterning in advanced semiconductor manufacturing. 展开更多
关键词 photolithographic limits isothermal annealing method mitigating environmental fluctuations e block copolymer bcp annealing films high resolution lithography isothermal annealing microenvironment driven
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Flexible,high-density,laminated ECoG electrode array for high spatiotemporal resolution foci diagnostic localization of refractory epilepsy 被引量:2
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作者 Yafeng Liu Zhouheng Wang +4 位作者 Yang Jiao Ying Chen Guangyuan Xu Yinji Ma Xue Feng 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期388-398,共11页
High spatiotemporal resolution brain electrical signals are critical for basic neuroscience research and high-precision focus diagnostic localization,as the spatial scale of some pathologic signals is at the submillim... High spatiotemporal resolution brain electrical signals are critical for basic neuroscience research and high-precision focus diagnostic localization,as the spatial scale of some pathologic signals is at the submillimeter or micrometer level.This entails connecting hundreds or thousands of electrode wires on a limited surface.This study reported a class of flexible,ultrathin,highdensity electrocorticogram(ECoG)electrode arrays.The challenge of a large number of wiring arrangements was overcome by a laminated structure design and processing technology improvement.The flexible,ultrathin,high-density ECoG electrode array was conformably attached to the cortex for reliable,high spatial resolution electrophysiologic recordings.The minimum spacing between electrodes was 15μm,comparable to the diameter of a single neuron.Eight hundred electrodes were prepared with an electrode density of 4444 mm^(-2).In focal epilepsy surgery,the flexible,high-density,laminated ECoG electrode array with 36 electrodes was applied to collect epileptic spike waves inrabbits,improving the positioning accuracy of epilepsy lesions from the centimeter to the submillimeter level.The flexible,high-density,laminated ECoG electrode array has potential clinical applications in intractable epilepsy and other neurologic diseases requiring high-precision electroencephalogram acquisition. 展开更多
关键词 Electrocorticogram(ECoG)electrode EPILEPSY high density high resolution Laminated structure
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Very Low Earth Orbit Satellites Promise Greater Resolution...and Less Privacy
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作者 Chris Palmer 《Engineering》 2025年第3期6-8,共3页
In February 2025,a startup satellite manufacturer,Albedo(Broomfield,CO,USA)is expected to launch its first satellite,Clarity-1,into orbit aboard SpaceX’s Transporter-13,a Falcon 9 rideshare mission[1].Like many imagi... In February 2025,a startup satellite manufacturer,Albedo(Broomfield,CO,USA)is expected to launch its first satellite,Clarity-1,into orbit aboard SpaceX’s Transporter-13,a Falcon 9 rideshare mission[1].Like many imaging satellites,Clarity-1’s mis-sion will be to take high-resolution aerial photos for clients in var-ious economic sectors including agriculture,insurance,energy,mapping,utilities,and defense.What makes this satellite unique is both its industry-leading 10 cm spatial resolution and its extre-mely low orbit of 200 km,far closer to Earth than the 450 km or higher orbits of most of its peers with similar missions. 展开更多
关键词 imaging satellitesclarity s spatial resolution high resolution imaging satellites low earth orbit aerial photos
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Synthesizing high-resolution satellite salinity data based on multi-fractal fusion
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作者 Hengqian Yan Jian Shi +3 位作者 Ren Zhang Wangjiang Hu Yongchui Zhang Mei Hong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期112-124,共13页
The spaceborne platform has unprecedently provided the global eddy-permitting(typically about 0.25°)products of sea surface salinity(SSS),however the existing SSS products can hardly resolve mesoscale motions due... The spaceborne platform has unprecedently provided the global eddy-permitting(typically about 0.25°)products of sea surface salinity(SSS),however the existing SSS products can hardly resolve mesoscale motions due to the heavy noises therein and the over-smoothing in denoising processes.By means of the multi-fractal fusion(MFF),the high-resolution SSS product is synthesized with the template of sea surface temperature(SST).Two low-resolution SSS products and four SST products are considered as the source data and the templates respectively to determine the best combination.The fused products are validated by the in situ observations and intercompared via SSS maps,Singularity Exponent maps and wavenumber spectra.The results demonstrate that the MFF can perform a good work in mitigating the noises and improving the resolution.The combination of the climate change initiative SSS and the remote sensing system SST can produce the 0.1°denoised product whose global mean standard derivation of salinity against Argo is 0.21 and the feature resolution can reach 30−40 km. 展开更多
关键词 sea surface salinity multi-fractal fusion high resolution
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Development of an automatic measurement system using atmospheric pressure photoionization ultrahigh-resolution mass spectrometry and application for on-line analysis of particulate matter
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作者 Yayuan Dong Ranran Liu +4 位作者 Ling Xie Xiaole Pan Yele Sun Lin Wu ZifaWang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第4期516-530,共15页
On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real tim... On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real time.Here we describe the development and application of an automatic measurement system that incorporates PM_(2.5)sampling,thermal desorption,atmospheric pressure photoionization,and UHRMS analysis.Molecular formulas of detected organic compounds were deducted from the accurate(±10 ppm)molecular weights obtained at a mass resolution of 100,000,allowing the identification of small organic compounds in PM_(2.5).Detection efficiencies of 28 standard compounds were determined and we found a high sensitivity and selectivity towards organic amines with limits of detection below 10 pg.As a proof of principle,PM_(2.5)samples collected off-line in winter in the urban area of Beijing were analyzed using the Ionization Module and HRMS of the system.The automatic system was then applied to conduct on-line measurements during the summer time at a time resolution of 2 hr.The detected organic compounds comprised mainly CHON and CHN compounds below 350 m/z.Pronounced seasonal variations in elemental composition were observed with shorter carbon backbones and higher O/C ratios in summer than that in winter.This result is consistent with stronger photochemical reactions and thus a higher oxidation state of organics in summer.Diurnal variation in signal intensity of each formula provides crucial information to reveal its source and formation pathway.In summary,the automatic measurement system serves as an important tool for the on-line characterization and identification of organic species in PM_(2.5). 展开更多
关键词 PM_(2.5) Chemical composition On-line measurement technique high resolution mass spectrometry
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Revisting High-Resolution Schemes with van Albada Slope Limiter
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作者 Jingcheng Lu Eitan Tadmor 《Communications on Applied Mathematics and Computation》 EI 2024年第3期1924-1953,共30页
Slope limiters play an essential role in maintaining the non-oscillatory behavior of high-resolution methods for nonlinear conservation laws.The family of minmod limiters serves as the prototype example.Here,we revisi... Slope limiters play an essential role in maintaining the non-oscillatory behavior of high-resolution methods for nonlinear conservation laws.The family of minmod limiters serves as the prototype example.Here,we revisit the question of non-oscillatory behavior of high-resolution central schemes in terms of the slope limiter proposed by van Albada et al.(Astron Astrophys 108:76–84,1982).The van Albada(vA)limiter is smoother near extrema,and consequently,in many cases,it outperforms the results obtained using the standard minmod limiter.In particular,we prove that the vA limiter ensures the one-dimensional Total-Variation Diminishing(TVD)stability and demonstrate that it yields noticeable improvement in computation of one-and two-dimensional systems. 展开更多
关键词 high resolution LIMITERS Total-Variation Diminishing(TVD)stability Central schemes
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The environmental analysis and site selection of mussel and large yellow croaker aquaculture areas based on high resolution remote sensing
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作者 Lina Cai Jie Yin +3 位作者 Xiaojun Yan Yongdong Zhou Rong Tang Menghan Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期66-86,共21页
Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was propose... Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was proposed and applied to determine the basic environmental characteristics of the best mussel and large yellow croaker aquaculture areas.This methodology includes the first step of extraction of the location distribution and the second step of the extraction of internal environmental factors.The fishery ranching index(FRI1,FRI2)was established to extract the mussel and the large yellow croaker aquaculture area in Zhoushan,using Gaofen-1(GF-1)and Gaofen-6(GF-6)satellite data with a special resolution of 2 m.In the second step,the environmental factors such as sea surface temperature(SST),chlorophyll a(Chl-a)concentration,current and tide,suspended sediment concentration(SSC)in mussel aquaculture area and large yellow croaker aquaculture area were extracted and analyzed in detail.The results show the following three points.(1)For the extraction of the mussel aquaculture area,FRI1 and FRI2 are complementary,and the combination of FRI1 and FRI2 is suitable to extract the mussel aquaculture area.As for the large yellow croaker aquaculture area extraction,FRI2 is suitable.(2)Mussel aquaculture and the large yellow croaker aquaculture area in Zhoushan are mainly located on the side near the islands that are away from the eastern open waters.The water environment factor template suitable for mussel and large yellow croaker aquaculture was determined.(3)This two-step remote sensing method can be used for the preliminary screening of potential site selection for the mussels and large yellow croaker aquaculture area in the future.the fishery ranching index(FRI1,FRI2)in this paper can be applied to extract the mussel and large yellow croaker aquaculture areas in coastal waters around the world. 展开更多
关键词 mussel aquaculture area large yellow croaker aquaculture area high resolution satellite site selection environmental analysis
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Impact of molecular composition on viscosity of heavy oil: Machine learning based on semi-quantitative analysis results from high-resolution mass spectrometry
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作者 Qian-Hui Zhao Jian-Xun Wu +2 位作者 Tian-Hang Zhou Suo-Qi Zhao Quan Shi 《Petroleum Science》 CSCD 2024年第6期4446-4453,共8页
The primary impediment to the recovery of heavy oil lies in its high viscosity, which necessitates a deeper understanding of the molecular mechanisms governing its dynamic behavior for enhanced oil recovery. However, ... The primary impediment to the recovery of heavy oil lies in its high viscosity, which necessitates a deeper understanding of the molecular mechanisms governing its dynamic behavior for enhanced oil recovery. However, there remains a dearth of understanding regarding the complex molecular composition inherent to heavy oil. In this study, we employed high-resolution mass spectrometry in conjunction with various chemical derivatization and ionization methods to obtain semi-quantitative results of molecular group compositions of 35 heavy oils. The gradient boosting(GB) model has been further used to acquire the feature importance rank(FIR). A feature is an independently observable property of the observed object. Feature importance can measure the contribution of each input feature to the model prediction result, indicate the degree of correlation between the feature and the target,unveil which features are indicative of certain predictions. We have developed a framework for utilizing physical insights into the impact of molecular group compositions on viscosity. The results of machine learning(ML) conducted by GB show that the viscosity of heavy oils is primarily influenced by light components, specifically small molecular hydrocarbons with low condensation degrees, as well as petroleum acids composed of acidic oxygen groups and neutral nitrogen groups. Additionally, large molecular aromatic hydrocarbons and sulfoxides also play significant roles in determine the viscosity. 展开更多
关键词 Heavy oil high resolution mass spectrometry Machine learning VISCOSITY
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Spatial-temporal distribution and geochemistry of highly evolved Mesozoic granites in Great Xing’an Range,NE China:Discriminant criteria and geological significance
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作者 WU Haoran YANG Hao +4 位作者 GE Wenchun JI Zheng DONG Yu JING Yan JING Jiahao 《Global Geology》 2024年第1期20-34,共15页
Highly evolved granite is an important sign of the mature continent crust and closely associated with deposits of rare metals.In this work,the authors undertake systematically zircon U-Pb ages and whole rock elemental... Highly evolved granite is an important sign of the mature continent crust and closely associated with deposits of rare metals.In this work,the authors undertake systematically zircon U-Pb ages and whole rock elemental data for highly evolved granitic intrusions from the Great Xing’an Range(GXR),NE China,to elucidate their discriminant criteria,spatial-temporal distribution,differentiation and geodynamic mecha-nism.Geochemical data of these highly evolved granites suggest that high w(SiO_(2))(>70%)and differentiation index(DI>88)could be quantified indicators,while strong Eu depletion,high TE_(1,3),lowΣREE and low Zr/Hf,Nb/Ta,K/Rb could only be qualitative indicators.Zircon U-Pb ages suggest that the highly evolved gran-ites in the GXR were mainly formed in Late Mesozoic,which can be divided into two major stages:Late Ju-rassic-early Early Cretaceous(162-136 Ma,peak at 138 Ma),and late Early Cretaceous(136-106 Ma,peak at 126 Ma).The highly evolved granites are mainly distributed in the central-southern GXR,and display a weakly trend of getting younger from northwest to southeast,meanwhile indicating the metallogenic potential of rare metals within the central GXR.The spatial-temporal distribution,combined with regional geological data,indicates the highly evolved Mesozoic granites in the GXR were emplaced in an extensional environ-ment,of which the Late Jurassic-early Early Cretaceous extension was related to the closure of the Mongol-Okhotsk Ocean and roll-back of the Paleo-Pacific Plate,while the late Early Cretaceous extension was mainly related to the roll-back of the Paleo-Pacific Plate. 展开更多
关键词 highly evolved granite Great Xing’an Range spatial-temporal distribution extensional environment
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Ground-based remote sensing of nitrous oxide(N_(2)O)over Hefei,eastern China from high-resolution solar spectra
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作者 Youwen Sun Hao Yin +2 位作者 Wei Wang Changgong Shan Cheng Liu 《Geo-Spatial Information Science》 CSCD 2024年第6期1931-1942,共12页
We for the first time demonstrate ground-based remote sensing of Nitrous Oxide(N_(2)O)over Hefei in eastern China from high resolution Fourier Transform Infra-Red(FTIR)solar spectra.We have retrieved Column-averaged A... We for the first time demonstrate ground-based remote sensing of Nitrous Oxide(N_(2)O)over Hefei in eastern China from high resolution Fourier Transform Infra-Red(FTIR)solar spectra.We have retrieved Column-averaged Abundance of N_(2)O(XN_(2)O)from both Near-Infrared(NIR,4000 to 11,000 cm−1)and Mid-Infrared(MIR,2400 to 3200 cm−1)solar spectra and inspected their agreement.Generally,NIR and MIR measurements agree well with a correlation coefficient of 0.86 and an average difference of(1.33±4.05)ppbv(NIR-MIR).By correcting the bias of the two datasets,we combine the NIR and MIR measurements to investigate seasonality and inter-annual trend of XN_(2)O over Hefei.The observed monthly mean time series of XN_(2)O minimize in June and maximize in September,with values of(316.55±12.22)ppbv and(322.05±12.93)ppbv,respectively.The XN_(2)O time series from 2015 to 2020 showed an inter-annual trend of(0.53±0.10)%/year over Hefei,China.We also compared the FTIR XN_(2)O observations with GEOS-Chem model XN_(2)O simulations.They are in reasonable agreement with a correlation coefficient(R)of 0.71,but GEOS-Chem model underestimated the seasonality of the observations.This study can enhance current knowledge of ground-based high-resolution FTIR remote sensing of N_(2)O in the atmosphere and contribute to generating a new reliable N_(2)O dataset for climate change research. 展开更多
关键词 Greenhouse Gases(GHGs) remote sensing high resolution Fourier Transform Infra-Red(FTIR)
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Shading aware DSM generation from high resolution multi-view satellite images
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作者 Zhihua Hu Pengjie Tao +1 位作者 Xiaoxiang Long Haiyan Wang 《Geo-Spatial Information Science》 CSCD 2024年第2期398-407,共10页
In many cases,the Digital Surface Models(DSMs)and Digital Elevation Models(DEMs)are obtained with Light Detection and Ranging(LiDAR)or stereo matching.As an active method,LiDAR is very accurate but expensive,thus ofte... In many cases,the Digital Surface Models(DSMs)and Digital Elevation Models(DEMs)are obtained with Light Detection and Ranging(LiDAR)or stereo matching.As an active method,LiDAR is very accurate but expensive,thus often limiting its use in small-scale acquisition.Stereo matching is suitable for large-scale acquisition of terrain information as the increase of satellite stereo sensors.However,underperformance of stereo matching easily occurs in textureless areas.Accordingly,this study proposed a Shading Aware DSM GEneration Method(SADGE)with high resolution multi-view satellite images.Considering the complementarity of stereo matching and Shape from Shading(SfS),SADGE combines the advantage of stereo matching and SfS technique.First,an improved Semi-Global Matching(SGM)technique is used to generate an initial surface expressed by a DSM;then,it is refined by optimizing the objective function which modeled the imaging process with the illumination,surface albedo,and normal object surface.Different from the existing shading-based DEM refinement or generation method,no information about the illumination or the viewing angle is needed while concave/convex ambiguity can be avoided as multi-view images are utilized.Experiments with ZiYuan-3 and GaoFen-7 images show that the proposed method can generate higher accuracy DSM(12.5-56.3%improvement)with sound overall shape and temporarily detailed surface compared with a software solution(SURE)for multi-view stereo. 展开更多
关键词 Shape from Shading(SfS) multi-view stereo Digital Surface Model(DSM) high resolution multi-view satellite images
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High-Resolution Remote Sensing Imagery for the Recognition of Traditional Villages
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作者 Mengchen Wang Linshuhong Shen 《Journal of Architectural Research and Development》 2024年第1期75-83,共9页
Traditional Chinese villages,vital carriers of traditional culture,have faced significant alterations due to urbanization in recent years,urgently necessitating artificial intelligence data updates.This study integrat... Traditional Chinese villages,vital carriers of traditional culture,have faced significant alterations due to urbanization in recent years,urgently necessitating artificial intelligence data updates.This study integrates high spatial resolution remote sensing imagery with deep learning techniques,proposing a novel method for identifying rooftops of traditional Chinese village buildings using high-definition remote sensing images.Using 0.54 m spatial resolution imagery of traditional village areas as the data source,this method analyzes the geometric and spectral image characteristics of village building rooftops.It constructs a deep learning feature sample library tailored to the target types.Employing a semantically enhanced version of the improved Mask R-CNN(Mask Region-based Convolutional Neural Network)for building recognition,the study conducts experiments on localized imagery from different regions.The results demonstrated that the modified Mask R-CNN effectively identifies traditional village building rooftops,achieving an of 0.7520 and an of 0.7400.It improves the current problem of misidentification and missed detection caused by feature heterogeneity.This method offers a viable and effective approach for industrialized data monitoring of traditional villages,contributing to their sustainable development. 展开更多
关键词 Traditional villages Building rooftops high spatial resolution remote sensing Instance segmentation
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High resolution GPR and its experimental study 被引量:3
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作者 黄玲 曾昭发 +1 位作者 王牧男 王者江 《Applied Geophysics》 SCIE CSCD 2007年第4期301-307,共7页
We develop a high resolution ground penetrating radar system (LANRCS-GPR) based on the E5071B Vector Network Analyzer (VNA). This system takes advantage of a wideband and adjustable frequency domain ground penetra... We develop a high resolution ground penetrating radar system (LANRCS-GPR) based on the E5071B Vector Network Analyzer (VNA). This system takes advantage of a wideband and adjustable frequency domain ground penetrating radar system and adds the characteristics of a network analyzer with ultra-wideband and high precision measurement. It adopts the LAN mode to concatenate system control that reduces construction cost and makes the system easy to expand. The high resolution ground penetrating radar system carries out real time imaging using F-K migration with high calculation efficiency. The experiment results of the system indicate that the LANRCS-GPR system provides high resolution and precision, high signal-to-noise ratio, and great dynamic range. Furthermore, the LANRCS-GPR system is flexible and reliable to operate with easy to expand system functions. The research and development of the LANRCS-GPR provide the theoretical and experimental foundation for future frequency domain ground penetrating radar production and also can serve as an experimental platform with high data gathering precision, enormous information capability, wide application, and convenient operation for electromagnetic wave research and electromagnetic exploration. 展开更多
关键词 high resolution ground penetrating radar vector network analyzer and frequency domain
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