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Multilevel encapsulation-engineered ultra-stable flexible scintillator films for high-resolution X-ray imaging
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作者 Mengke Bai Rui Zhang +13 位作者 Jiahuan Guo Fei Zhang Yurun Liang Mengke Li Yingyu Zhou Xue Yan Yubo Wang Liyuan Wu Yuhang Hou Gaoyu Chen Yatao Zou Wenqing Liang Gaofeng Zhao Weidong Xu 《Science China Materials》 2026年第3期1440-1447,共8页
Lead halide perovskites have emerged as promising scintillators for X-ray imaging owing to their high Xray absorption efficiency,excellent luminescence properties,and facile synthesis.However,their intrinsic ionic nat... Lead halide perovskites have emerged as promising scintillators for X-ray imaging owing to their high Xray absorption efficiency,excellent luminescence properties,and facile synthesis.However,their intrinsic ionic nature poses a fundamental challenge in simultaneously achieving high photoluminescence efficiency and environmental robustness.Here,we introduce a multilevel encapsulation strategy by sequentially coating CsPbBr_(3)quantum dots(QDs)with Cs_(4)PbBr_(6),SiO_(2),and polydimethylsiloxane(PDMS),thereby synergistically enhancing both optical performance and stability.Cs_(4)PbBr_(6)effectively passivates surface defects of CsPbBr_(3)QDs,while the SiO_(2)and PDMS layers serve as protective barriers against moisture,heat,and radiation.The resulting CsPbBr_(3)@Cs_(4)PbBr_(6)/SiO_(2)/PDMS flexible films exhibit a high photoluminescence quantum yield of 85%,outstanding mechanical flexibility,and remarkable durability under stretching,bending,and compressing.Moreover,the films retain excellent emission stability under elevated temperatures,prolonged X-ray irradiation,and extended water immersion.X-ray imaging evaluations further demonstrate a spatial resolution of 12 lp/mm,enabling distortion-free imaging of curved objects,while their superior water resistance allows for long-term underwater X-ray imaging.This work highlights the critical role of hierarchical encapsulation in balancing luminescence efficiency and environmental stability,offering a viable pathway toward practical high-performance flexible perovskite scintillators. 展开更多
关键词 multilevel encapsulation CsPbBr_(3)quantum dots flexible scintillator environmental robustness x-ray imaging
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Tests of Solar X-Ray Image Reconstruction:Study of X-Ray Imaging Algorithms and Reconstruction Parameters 被引量:1
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作者 Wenhui Yu Yang Su +2 位作者 Zhentong Li Wei Chen Weiqun Gan 《Research in Astronomy and Astrophysics》 2025年第3期90-110,共21页
Imaging observations of solar X-ray bursts can reveal details of the energy release process and particle acceleration in flares.Most hard X-ray imagers make use of the modulation-based Fourier transform imaging method... Imaging observations of solar X-ray bursts can reveal details of the energy release process and particle acceleration in flares.Most hard X-ray imagers make use of the modulation-based Fourier transform imaging method,an indirect imaging technique that requires algorithms to reconstruct and optimize images.During the last decade,a variety of algorithms have been developed and improved.However,it is difficult to quantitatively evaluate the image quality of different solutions without a true,reference image of observation.How to choose the values of imaging parameters for these algorithms to get the best performance is also an open question.In this study,we present a detailed test of the characteristics of these algorithms,imaging dynamic range and a crucial parameter for the CLEAN method,clean beam width factor(CBWF).We first used SDO/AIA EUV images to compute DEM maps and calculate thermal X-ray maps.Then these realistic sources and several types of simulated sources are used as the ground truth in the imaging simulations for both RHESSI and ASO-S/HXI.The different solutions are evaluated quantitatively by a number of means.The overall results suggest that EM,PIXON,and CLEAN are exceptional methods for sidelobe elimination,producing images with clear source details.Although MEM_GE,MEM_NJIT,VIS_WV and VIS_CS possess fast imaging processes and generate good images,they too possess associated imperfections unique to each method.The two forward fit algorithms,VF and FF,perform differently,and VF appears to be more robust and useful.We also demonstrated the imaging capability of HXI and available HXI algorithms.Furthermore,the effect of CBWF on image quality was investigated,and the optimal settings for both RHESSI and HXI were proposed. 展开更多
关键词 techniques image processing-Sun flares-Sun x-rays gamma rays
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Manufacturing and testing of X-ray imaging components with high precision 被引量:5
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作者 HU Jia sheng WU Xü 《光学精密工程》 EI CAS CSCD 北大核心 2005年第5期620-625,共6页
关键词 X光线图像 质量评价 纳米 精度
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Tracing equatorward and poleward boundaries of the magnetospheric cusp from a simulated X-ray image
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作者 Xue Wang TianRan Sun +4 位作者 C.Philippe Escoubet Andy Read YiHong Guo Steve Sembay Chi Wang 《Earth and Planetary Physics》 2026年第1期144-155,共12页
A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-d... A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-dimensional cusp boundary from a two-dimensional X-ray image because the detected X-ray signals will be integrated along the line of sight.In this work,a global magnetohydrodynamic code was used to simulate the X-ray images and photon count images,assuming an interplanetary magnetic field with a pure Bz component.The assumption of an elliptic cusp boundary at a given altitude was used to trace the equatorward and poleward boundaries of the cusp from a simulated X-ray image.The average discrepancy was less than 0.1 RE.To reduce the influence of instrument effects and cosmic X-ray backgrounds,image denoising was considered before applying the method above to SXI photon count images.The cusp boundaries were reasonably reconstructed from the noisy X-ray image. 展开更多
关键词 SMILE mission x-ray image cusp boundary
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Precise and non-destructive approach for identifying the real concentration based on cured cemented paste backfill using hyperspectral imaging
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作者 Qing Na Qiusong Chen Aixiang Wu 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期116-128,共13页
Cemented paste backfill(CPB)is a technology that achieves safe mining by filling the goaf with waste rocks,tailings,and other materials.It is an inevitable choice to deal with the development of deep and highly diffic... Cemented paste backfill(CPB)is a technology that achieves safe mining by filling the goaf with waste rocks,tailings,and other materials.It is an inevitable choice to deal with the development of deep and highly difficult mines and meet the requirements of environmental protection and safety regulations.It promotes the development of a circular economy in mines through the development of lowgrade resources and the resource utilization of waste,and extends the service life of mines.The mass concentration of solid content(abbreviated as“concentration”)is a critical parameter for CPB.However,discrepancies often arise between the on-site measurements and the pre-designed values due to factors such as groundwater inflow and segregation within the goaf,which cannot be evaluated after the solidification of CPB.This paper innovatively provides an in-situ non-destructive approach to identify the real concentration of CPB after curing for certain days using hyperspectral imaging(HSI)technology.Initially,the spectral variation patterns under different concentration conditions were investigated through hyperspectral scanning experiments on CPB samples.The results demonstrate that as the CPB concentration increases from 61wt%to 73wt%,the overall spectral reflectance gradually increases,with two distinct absorption peaks observed at 1407 and 1917 nm.Notably,the reflectance at 1407 nm exhibited a strong linear relationship with the concentration.Subsequently,the K-nearest neighbors(KNN)and support vector machine(SVM)algorithms were employed to classify and identify different concentrations.The study revealed that,with the KNN algorithm,the highest accuracy was achieved when K(number of nearest neighbors)was 1,although this resulted in overfitting.When K=3,the model displayed the optimal balance between accuracy and stability,with an accuracy of 95.03%.In the SVM algorithm,the highest accuracy of 98.24%was attained with parameters C(regularization parameter)=200 and Gamma(kernel coefficient)=10.A comparative analysis of precision,accuracy,and recall further highlighted that the SVM provided superior stability and precision for identifying CPB concentration.Thus,HSI technology offers an effective solution for the in-situ,non-destructive monitoring of CPB concentration,presenting a promising approach for optimizing and controlling CPB characteristic parameters. 展开更多
关键词 cemented paste backfill CONCENTRATION hyperspectral imaging non-destructive testing
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In‑Operando X‑Ray Imaging for Sobering Examination of Aqueous Zinc Metal Batteries
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作者 Yuhang Dai Hongzhen He +4 位作者 Mengzheng Ouyang Jianuo Chen Jie Lin Haobo Dong Guanjie He 《Nano-Micro Letters》 2026年第3期330-337,共8页
Aqueous zinc metal batteries(AZMBs)face significant challenges in achieving reversibility and cycling stability,primarily due to hydrogen evolution reactions(HER)and zinc dendrite growth.In this study,by employing car... Aqueous zinc metal batteries(AZMBs)face significant challenges in achieving reversibility and cycling stability,primarily due to hydrogen evolution reactions(HER)and zinc dendrite growth.In this study,by employing carefully designed cells that approximate the structural characteristics of practical batteries,we revisit this widely held view through in-operando X-ray radiography to examine zinc dendrite formation and HER under nearpractical operating conditions.While conventional understanding emphasizes the severity of these processes,our findings suggest that zinc dendrites and HER are noticeably less pronounced in dense,real-operation configurations compared to modified cells,possibly due to a more uniform electric field and the suppression of triple-phase boundaries.This study indicates that other components,such as degradation at the cathode current collector interface and configuration mismatches within the full cell,may also represent important barriers to the practical application of AZMBs,particularly during the early stages of electrodeposition. 展开更多
关键词 Aqueous Zn metal batteries x-ray imaging In situ characterization Degradation mechanism
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Tests of Solar X-Ray Image Reconstruction:A New Index for Assessing Image Quality 被引量:1
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作者 Zhen-Tong Li Wen-Hui Yu +2 位作者 Yang Su Wei Chen Wei-Qun Gan 《Research in Astronomy and Astrophysics》 2025年第3期76-89,共14页
Indirect X-ray modulation imaging has been adopted in a number of solar missions and provided reconstructed X-ray images of solar flares that are of great scientific importance.However,the assessment of the image qual... Indirect X-ray modulation imaging has been adopted in a number of solar missions and provided reconstructed X-ray images of solar flares that are of great scientific importance.However,the assessment of the image quality of the reconstruction is still difficult,which is particularly useful for scheme design of X-ray imaging systems,testing and improvement of imaging algorithms,and scientific research of X-ray sources.Currently,there is no specified method to quantitatively evaluate the quality of X-ray image reconstruction and the point-spread function(PSF)of an X-ray imager.In this paper,we propose percentage proximity degree(PPD)by considering the imaging characteristics of X-ray image reconstruction and in particular,sidelobes and their effects on imaging quality.After testing a variety of imaging quality assessments in six aspects,we utilized the technique for order preference by similarity to ideal solution to the indices that meet the requirements.Then we develop the final quality index for X-ray image reconstruction,QuIX,which consists of the selected indices and the new PPD.QuIX performs well in a series of tests,including assessment of instrument PSF and simulation tests under different grid configurations,as well as imaging tests with RHESSI data.It is also a useful tool for testing of imaging algorithms,and determination of imaging parameters for both RHESSI and ASO-S/Hard X-ray Imager,such as field of view,beam width factor,and detector selection. 展开更多
关键词 SUN flares-Sun x-rays gamma-rays-techniques image processing
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Evaporation-Processed X-Ray Imaging Scintillation Screen Based on Copper Clusters
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作者 Xie Gaozhan Chen Cheng +9 位作者 Zhang Jingru Xiao Dongjie Cai Minyue Gao Qiya Gao Zhisheng Sun Chengxi Li Hui Li Huanhuan Chen Runfeng Tao Ye 《有机化学》 北大核心 2025年第11期4219-4226,共8页
Organic-inorganic hybrid clusters with strong X-ray radioluminescence have exhibited great potential in scintillator field.However,fabricating the X-ray imaging screens of the clusters without sacrificing the scintill... Organic-inorganic hybrid clusters with strong X-ray radioluminescence have exhibited great potential in scintillator field.However,fabricating the X-ray imaging screens of the clusters without sacrificing the scintillation performance is challenging.Herein,we report an effective way to prepare high-quality scintillation films of two synthesized Cu(Ⅰ)clusters through vacuum evaporation deposition.The developed Cu(Ⅰ)clusters with rigid molecular structures show excellent scintillation performance with a high light yield of up to 19356.7 photons/MeV and a low detection limit of 158 nGy/s.The scintillation film based on the Cu(Ⅰ)clusters made by vacuum evaporation deposition is highly uniform with a small surface roughness value of 1.04 nm,which can be applied to X-ray imaging for various objects.These results not only provide important guidance to develop high-performance organic-inorganic hybrid scintillators,but also pave a straightforward way to prepare non-doped scintillation screens for remarkable X-ray imaging applications. 展开更多
关键词 scintillator RADIOLUMINESCENCE Cu(Ⅰ)clusters vacuum evaporation deposition x-ray imaging
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Lead-free Ba_(2)LaNbO_(6):Eu^(3+) phosphors with Bi^(3+)-enhanced photochromism for dual-mode X-ray detection and 3D imaging
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作者 Yueteng Zhang Zan Xu +5 位作者 Xue Bai Heping Zhao Jianbei Qiu Zhiguo Song Jiayan Liao Zhengwen Yang 《Journal of Materials Science & Technology》 2025年第32期156-166,共11页
This study explores the application of X-ray-induced photochromism and photoluminescence in optical storage,anti-counterfeiting,non-destructive testing,and high-resolution X-ray detection and imaging.Ba_(2)LaNbO_(6):B... This study explores the application of X-ray-induced photochromism and photoluminescence in optical storage,anti-counterfeiting,non-destructive testing,and high-resolution X-ray detection and imaging.Ba_(2)LaNbO_(6):Bi,Eu phosphors were synthesized,with Bi enhancing X-ray-induced photochromic prop-erties.Under X-ray irradiation,the phosphors transfer from white to red in bright field conditions and emit red photoluminescence in dark field conditions.Exposure to 470 nm ultraviolet light induces rapid bleaching.The mechanisms of photochromism and photoluminescence,particularly Bi's role as a colorant,were systematically investigated.The Ba_(2)LaNbO_(6):Bi,Eu phosphors film achieves high resolution,high-lighting its potential for X-ray imaging and non-destructive testing.Furthermore,the flexible Ba_(2)LaNbO_(6):Bi,Eu film supports dual-mode imaging and detection,addressing the limitations of traditional flat dis-plays in 3D imaging. 展开更多
关键词 Lead-free double perovskite x-ray detection x-ray imaging Non-destructive testing
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Signal estimation bias in x-ray dark-field imaging using dual phase grating interferometer
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作者 Zhi-Li Wang Zun Zhang +1 位作者 Heng Chen Xin Ge 《Chinese Physics B》 2025年第3期550-558,共9页
In x-ray dark-field imaging using dual phase grating interferometer,multi-contrast signals are extracted from a set of acquired phase-stepping data by using the least-squares fitting algorithm.The extracted mean inten... In x-ray dark-field imaging using dual phase grating interferometer,multi-contrast signals are extracted from a set of acquired phase-stepping data by using the least-squares fitting algorithm.The extracted mean intensity,amplitude and visibility signals may be intrinsically biased.However,it is still unclear how large these biases are and how the data acquisition parameters influence the biases in the extracted signals.This work set out to address these questions.Analytical expressions of the biases of the extracted signals were theoretically derived by using a second-order Taylor series expansion.Extensive numerical simulations were performed to validate the theoretical results.It is illustrated that while the estimated mean intensity signal is always unbiased,the estimated amplitude and visibility signals are both positively biased.While the biases of the estimated amplitude signals are proportional to the inverse of the total number of phase steps,the biases of the estimated visibility signals are inversely proportional to the product of the total number of phase steps and the mean number of photons counted per phase step.Meanwhile,it is demonstrated that the dependence of the biases on the mean visibility is quite different from that of Talbot-Lau interferometer due to the difference in the intensity model.We expect that these results can be useful for data acquisition optimizations and interpretation of x-ray dark-field images. 展开更多
关键词 x-ray imaging dual phase grating interferometer dark-field imaging signal bias
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Smartphone-assisted electrochemiluminescence imaging test strips towards dual-signal visualized and sensitive monitoring of aflatoxin B1 in corn samples
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作者 Miao-Miao Chen Min-Ling Zhang +5 位作者 Xiao Song Jun Jiang Xiaoqian Tang Qi Zhang Xiuhua Zhang Peiwu Li 《Chinese Chemical Letters》 2025年第1期464-468,共5页
Aflatoxins B1(AFB1)contamination in agro-food holds great threaten to human and animal health.Conventional test strips for rapid AFB1 visualized monitoring remains challenged by improvement of sensitivity and matrix i... Aflatoxins B1(AFB1)contamination in agro-food holds great threaten to human and animal health.Conventional test strips for rapid AFB1 visualized monitoring remains challenged by improvement of sensitivity and matrix interference resistance.In this case,we developed a portable electrochemiluminescence(ECL)imaging test strip with dual-signal outputs for AFB1 quantification in corn samples.RuPEI@SiO_(2)@Au nanospheres were synthesized for bonding with anti-AFB1 antibody and then colorimetrical signal-reported on test line through the capillary flow at strips.Meanwhile,ECL imaging signal of the constructed carbon-ink-based working electrode on polyvinyl chloride substrate of strips was exported under an applied potential of 1.25 V.The whole ECL test strips not only endowed convenient colorimetric responses but guaranteed quick-witted ECL image distinguishment even at extremely low AFB1 content.The detection limit of this ECL imaging-integrated mode was 10-fold lower than that of only colorimetric mode.Furthermore,satisfactory selectivity,reliability and practicability of the as-proposed ECL test strips were demonstrated.This work offered a promising platform for on-site,accurate and sensitive detection of pollutants in foods. 展开更多
关键词 Electrochemiluminescence imaging test strips Nanomaterials Dual-signal outputs Aflatoxin B1 Food safety
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Thin layer identification using a theoretical X-ray logging while drilling(LWD)density imaging tool
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作者 Wen-Bin He Ji-Lin Fan +3 位作者 Qiong Zhang Ya Jin Wei Yuan Quan-Wen Zhang 《Petroleum Science》 2025年第6期2403-2413,共11页
With the increasing demand for oil exploration and subsurface resource development,density imaging plays an increasingly important role in identifying thin layers.However,conventional density imaging tools are limited... With the increasing demand for oil exploration and subsurface resource development,density imaging plays an increasingly important role in identifying thin layers.However,conventional density imaging tools are limited by poor vertical resolution and therefore suffer from errors in accurately estimating the thickness and relative dip angle of thin layers.This affects the accurate evaluation of thin layer oil and gas reserves.To address this issue,this study evaluates the feasibility of employing novel methods based on advanced tool design.First,an electronically controllable X-ray source is selected to replace the traditional Cs-137 source,aiming to improve the tool's vertical resolution while reducing the radioactive risks commonly associated with chemical sources.Simulation results show that the X-ray tool provides sufficient depth of investigation with better vertical resolution while maintaining the same level of measurement sensitivity.Once the tool design is established,Fisher's optimal segmentation method is improved to enhance the estimation of thin layer thickness and relative dip angle.This is completed by transforming identifying thin layer interface into a mathematical clustering problem.The thin layer interface is fitted using the nonlinear least squares method,which enables the calculation of its parameters.The results demonstrate a 38.5%reduction in RMSE(root mean square error)for thin layer thickness and a 33.7%reduction in RMSE for relative dip angle,demonstrating the superior performance of enhanced X-ray tool in thin layer identification.This study provides a new perspective on the design of density imaging tools and assessment of thin layer,which can help in future thin layer hydrocarbon reserves evaluation and development decisions. 展开更多
关键词 LWD density imaging x-ray tool design Thin layer identification
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Parallax-free panoramic X-ray imaging combined with minimally invasive plate osteosynthesis for treating proximal humeral shaft fractures
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作者 Wen-Jing Cheng Jing-Shun Lu +2 位作者 Zhou-Shan Tao Jia-Bing Xie Min Yang 《World Journal of Orthopedics》 2025年第5期44-50,共7页
BACKGROUND The objective of this study was to evaluate the use of combined parallax-free panoramic X-ray imaging during surgery by enabling the mobile C-arm with minimally invasive plate osteosynthesis(MIPO)in the man... BACKGROUND The objective of this study was to evaluate the use of combined parallax-free panoramic X-ray imaging during surgery by enabling the mobile C-arm with minimally invasive plate osteosynthesis(MIPO)in the management of proximal humeral shaft fractures.AIM To evaluate parallax-free panoramic X-ray images during surgery.METHODS A retrospective series of 17 proximal humeral shaft fractures were treated using combined parallax-free panoramic X-ray imaging during surgery by enabling the mobile C-arm with MIPO.The operating time and radiation exposure time were recorded,and early postoperative physical therapy and partial weight bearing were encouraged.Patients were followed at regular intervals and evaluated radiographically and clinically.RESULTS The mean operating time and radiation time were 73(range,49-95)minutes and 57(range:36-98)seconds,respectively.No complications occurred during the operation.All fractures healed at an average of 16.9(range:15-23)weeks.The average Constant-Murley score for all the patients was 89.5(range:75-100)points.None of the patients showed symptoms of vascular or nerve damage or wound infection.Three months after the operation,none of the patients developed subacromial impingement syndrome.No loosening or fracture of the implants occurred.The frontal and lateral radiographs showed good alignment.CONCLUSION We consider that MIPO with combined parallax-free panoramic X-ray imaging during surgery is an efficient method for treating proximal humeral shaft fractures,and could significantly reduce operative morbidity as well as lower the rate of intra-and postoperative complications. 展开更多
关键词 Minimally invasive plate osteosynthesis Proximal humeral shaft fractures Panoramic x-ray images COMPLICATIONS
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Attention U-Net for Precision Skeletal Segmentation in Chest X-Ray Imaging:Advancing Person Identification Techniques in Forensic Science
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作者 Hazem Farah Akram Bennour +3 位作者 Hama Soltani Mouaaz Nahas Rashiq Rafiq Marie Mohammed Al-Sarem 《Computers, Materials & Continua》 2025年第11期3335-3348,共14页
This study presents an advanced method for post-mortem person identification using the segmentation of skeletal structures from chest X-ray images.The proposed approach employs the Attention U-Net architecture,enhance... This study presents an advanced method for post-mortem person identification using the segmentation of skeletal structures from chest X-ray images.The proposed approach employs the Attention U-Net architecture,enhanced with gated attention mechanisms,to refine segmentation by emphasizing spatially relevant anatomical features while suppressing irrelevant details.By isolating skeletal structures which remain stable over time compared to soft tissues,this method leverages bones as reliable biometric markers for identity verification.The model integrates custom-designed encoder and decoder blocks with attention gates,achieving high segmentation precision.To evaluate the impact of architectural choices,we conducted an ablation study comparing Attention U-Net with and without attentionmechanisms,alongside an analysis of data augmentation effects.Training and evaluation were performed on a curated chest X-ray dataset,with segmentation performance measured using Dice score,precision,and loss functions,achieving over 98% precision and 94% Dice score.The extracted bone structures were further processed to derive unique biometric patterns,enabling robust and privacy-preserving person identification.Our findings highlight the effectiveness of attentionmechanisms in improving segmentation accuracy and underscore the potential of chest bonebased biometrics in forensic and medical imaging.This work paves the way for integrating artificial intelligence into real-world forensic workflows,offering a non-invasive and reliable solution for post-mortem identification. 展开更多
关键词 Bone extraction segmentation of skeletal structures chest x-ray images person identification deep learning attention mechanisms U-Net
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Feasibility Study for Applying Spectral Imaging for Wheat Grain Authenticity Testing in Pasta 被引量:4
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作者 Timothy Wilkes Gavin Nixon +3 位作者 Claire Bushell Adrian Waltho Amer Alroichdi Malcolm Burns 《Food and Nutrition Sciences》 2016年第5期355-361,共7页
Authentication of pasta is currently determined using molecular biology-based techniques focusing on DNA as the target analyte. Whilst proven to be effective, these approaches can be criticised as being destructive, t... Authentication of pasta is currently determined using molecular biology-based techniques focusing on DNA as the target analyte. Whilst proven to be effective, these approaches can be criticised as being destructive, time consuming, and requiring specialist instrument training. Advances in the field of multispectral imaging (MSI) and hyperspectral imaging (HSI) have facilitated the development of compact imaging platforms with the capability to rapidly differentiate a range of materials (inclusive of grains and seeds) based on surface colour, texture and chemical composition. This preliminary investigation evaluated the applicability of spectral imaging for identification and quantitation of durum wheat grain samples in relation to pasta authenticity. MSI and HSI were capable of rapidly distinguishing between durum wheat and adulterant common wheat cultivars and assigning percentage adulteration levels characterised by low biases and good repeatability estimates. The results demonstrated the potential for spectral imaging based seed/grain adulteration testing to augment existing standard molecular approaches for food authenticity testing. 展开更多
关键词 Spectral imaging Multispectral imaging Hyperspectral imaging Durum Wheat Authentication Rapid Non-Destructive testing Food Adulteration
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Recent developments in photoacoustic imaging and sensing for nondestructive testing and evaluation 被引量:3
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作者 Sung-Liang Chen Chao Tian 《Visual Computing for Industry,Biomedicine,and Art》 EI 2021年第1期50-62,共13页
Photoacoustic(PA)imaging has been widely used in biomedical research and preclinical studies during the past two decades.It has also been explored for nondestructive testing and evaluation(NDT/E)and for industrial app... Photoacoustic(PA)imaging has been widely used in biomedical research and preclinical studies during the past two decades.It has also been explored for nondestructive testing and evaluation(NDT/E)and for industrial applications.This paper describes the basic principles of PA technology for NDT/E and its applications in recent years.PA technology for NDT/E includes the use of a modulated continuous-wave laser and a pulsed laser for PA wave excitation,PA-generated ultrasonic waves,and all-optical PA wave excitation and detection.PA technology for NDT/E has demonstrated broad applications,including the imaging of railway cracks and defects,the imaging of Li metal batteries,the measurements of the porosity and Young’s modulus,the detection of defects and damage in silicon wafers,and a visualization of underdrawings in paintings. 展开更多
关键词 Photoacoustic imaging Photoacoustic sensing Nondestructive testing Nondestructive evaluation Photoacoustic microscopy
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Methodology development and application of X-ray imaging beamline at SSRF 被引量:12
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作者 Hong-Lan Xie Biao Deng +7 位作者 Guo-Hao Du Ya-Nan Fu Han Guo Yan-Ling Xue Guan-Yun Peng Fen Tao Ling Zhang Ti-Qiao Xiao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第10期74-94,共21页
This paper introduces some latest developments regarding the X-ray imaging methodology and applications of the X-ray imaging and biomedical application beamline(BL13W1)at Shanghai Synchrotron Radiation Facility in the... This paper introduces some latest developments regarding the X-ray imaging methodology and applications of the X-ray imaging and biomedical application beamline(BL13W1)at Shanghai Synchrotron Radiation Facility in the past 5 years.The photon energy range of the beamline is 8–72.5 keV.Several sets of X-ray imaging detectors with different pixel sizes(0.19–24 lm)are used to realize X-ray microcomputed tomography(X-ray micro-CT)and X-ray in-line phase-contrast imaging.To satisfy the requirements of user experiments,new X-ray imaging methods and image processing techniques are developed.In vivo dynamic micro-CT experiments with living insects are performed in 0.5 s(sampling rate of 2 Hz,2 tomograms/s)with a monochromatic beam from a wiggler source and in 40 ms(sampling rate of 25 Hz,25 tomograms/s)with a white beam from a bending magnet source.A new X-ray imaging method known as move contrast X-ray imaging is proposed,with which blood flow and moving tissues in raw images can be distinguished according to their moving frequencies in the time domain.Furthermore,X-ray speckle-tracking imaging with twice exposures to eliminate the edge enhancement effect is developed.A high-precision quantification method is realized to measure complex three-dimensional blood vessels obtained via X-ray micro-CT.X-ray imaging methods such as three-dimensional X-ray diffraction microscopy,small-angle X-ray scattering CT,and X-ray fluorescence CT are developed,in which the X-ray micro-CT imaging method is combined with other contrast mechanisms such as diffraction,scattering,and fluorescence contrasts respectively.Moreover,an X-ray nano-CT experiment is performed with a 100 nm spatial resolution.Typical user experimental results from the fields of material science,biomedicine,paleontology,physics,chemistry,and environmental science obtained on the beamline are provided. 展开更多
关键词 x-ray imaging x-ray in-line phase-contrast imaging x-ray micro-CT Dynamic micro-CT x-ray speckle-tracking imaging 3DXRD SAXS-CT x-ray fluorescence CT x-ray nano-CT Move contrast x-ray imaging
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A fast and adaptive method for automatic weld defect detection in various real-time X-ray imaging systems 被引量:10
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作者 邵家鑫 都东 +2 位作者 石涵 常保华 郭桂林 《China Welding》 EI CAS 2012年第1期8-12,共5页
A first and effective method is proposed to detect weld deject adaptively in various Dypes of real-time X-ray images obtained in different conditions. After weld extraction and noise reduction, a proper template of me... A first and effective method is proposed to detect weld deject adaptively in various Dypes of real-time X-ray images obtained in different conditions. After weld extraction and noise reduction, a proper template of median filter is used to estimate the weld background. After the weld background is subtracted from the original image, an adaptite threshold segmentation algorithm is proposed to obtain the binary image, and then the morphological close and open operation, labeling algorithm and fids'e alarm eliminating algorithm are applied to pracess the binary image to obtain the defect, ct detection result. At last, a fast realization procedure jbr proposed method is developed. The proposed method is tested in real-time X-ray image,s obtairted in different X-ray imaging sutems. Experiment results show that the proposed method is effective to detect low contrast weld dejects with few .false alarms and is adaptive to various types of real-time X-ray imaging systems. 展开更多
关键词 non-destructive testing real-time x-ray imaging weld defect automatie detection
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Combined molybdenum target X-ray and magnetic resonance imaging examinations improve breast cancer diagnostic efficacy 被引量:29
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作者 Wen-Quan Gu Sun-Mei Cai +3 位作者 Wei-Dong Liu Qi Zhang Ying Shi Li-Juan Du 《World Journal of Clinical Cases》 SCIE 2022年第2期485-491,共7页
BACKGROUND Early-stage breast cancer patients often lack specific clinical manifestations,making diagnosis difficult.Molybdenum target X-ray and magnetic resonance imaging(MRI)examinations both have their own advantag... BACKGROUND Early-stage breast cancer patients often lack specific clinical manifestations,making diagnosis difficult.Molybdenum target X-ray and magnetic resonance imaging(MRI)examinations both have their own advantages.Thus,a combined examination methodology may improve early breast cancer diagnoses.AIM To explore the combined diagnostic efficacy of molybdenum target X-ray and MRI examinations in breast cancer.METHODS Patients diagnosed with breast cancer at our hospital from March 2019 to April 2021 were recruited,as were the same number of patients during the same period with benign breast tumors.Both groups underwent molybdenum target X-ray and MRI examinations,and diagnoses were given based on each exam.The single(i.e.,X-ray or MRI)and combined(i.e.,using both methods)diagnoses were counted,and the MRI-related examination parameters(e.g.,T-wave peak,peak and early enhancement rates,and apparent diffusion coefficient)were compared between the groups.RESULTS In total,63 breast cancer patients and 63 benign breast tumor patients were recruited.MRI detected 53 breast cancer cases and 61 benign breast tumor cases.Molybdenum target X-ray detected 50 breast cancer cases and 60 benign breast tumor cases.The combined methodology detected 61 breast cancer cases and 61 benign breast tumor cases.The sensitivity(96.83%)and accuracy(96.83%)of the combined methodology were higher than single-method MRI(84.13%and 90.48%,respectively)and molybdenum target X-ray(79.37%and 87.30%,respectively)(P<0.05).The combined methodology specificity(96.83%)did not differ from singlemethod MRI(96.83%)or molybdenum target X-ray(95.24%)(P>0.05).The Twave peak(169.43±32.05)and apparent diffusion coefficient(1.01±0.23)were lower in the breast cancer group than in the benign tumor group(228.86±46.51 and 1.41±0.35,respectively).However,the peak enhancement rate(1.08±0.24)and early enhancement rate(1.07±0.26)were significantly higher in the breast cancer group than in the benign tumor group(0.83±0.19 and 0.75±0.19,respectively)(P<0.05).CONCLUSION Combined molybdenum target X-ray and MRI examinations for diagnosing breast cancer improved the diagnostic sensitivity and accuracy,minimizing the missedand misdiagnoses risks and promoting timely treatment intervention. 展开更多
关键词 MOLYBDENUM x-rays Magnetic resonance imaging Breast neoplasms Early diagnosis RADIOLOGY
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Application of Synchrotron X-Ray Imaging and Diffraction in Additive Manufacturing:A Review 被引量:6
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作者 Naying An Sansan Shuai +3 位作者 Tao Hu Chaoyue Chen Jiang Wang Zhongming Ren 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2022年第1期25-48,共24页
Additive manufacturing(AM)is a rapid prototyping technology based on the idea of discrete accumulation which off ers an advantage of economically fabricating a component with complex geometries in a rapid design-to-ma... Additive manufacturing(AM)is a rapid prototyping technology based on the idea of discrete accumulation which off ers an advantage of economically fabricating a component with complex geometries in a rapid design-to-manufacture cycle.However,various internal defects,such as balling,cracks,residual stress and porosity,are inevitably occurred during AM due to the complexity of laser/electron beam-powder interaction,rapid melting and solidification process,and microstructure evolution.The existence of porosity defects can potentially deteriorate the mechanical properties of selective laser melting(SLM)components,such as material stiff ness,hardness,tensile strength,and fatigue resistance performance.Synchrotron X-ray imaging and diffraction are important non-destructive means to elaborately characterize the internal defect characteristics and mechanical properties of AM parts.This paper presents a review on the application of synchrotron X-ray in identifying and verifying the quality and requirement of AM parts.Defects,microstructures and mechanical properties of printed components characterized by synchrotron X-ray imaging and diffraction are summarized in this review.Subsequently,this paper also elaborates on the online characterization of the evolution of the microstructure during AM using synchrotron X-ray imaging,and introduces the method for measuring AM stress by X-ray diffraction(XRD).Finally,the future application of synchrotron X-ray characterization in the AM is prospected. 展开更多
关键词 Additive manufacturing Synchrotron x-ray imaging x-ray diffraction Defect formation Mechanical properties Residual stress
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