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Analysis of the joint detection capability of the SMILE satellite and EISCAT-3D radar 被引量:2
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作者 JiaoJiao Zhang TianRan Sun +7 位作者 XiZheng Yu DaLin Li Hang Li JiaQi Guo ZongHua Ding Tao Chen Jian Wu Chi Wang 《Earth and Planetary Physics》 EI CSCD 2024年第1期299-306,共8页
The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite is a small magnetosphere–ionosphere link explorer developed cooperatively between China and Europe.It pioneers the use of X-ray imaging technology... The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite is a small magnetosphere–ionosphere link explorer developed cooperatively between China and Europe.It pioneers the use of X-ray imaging technology to perform large-scale imaging of the Earth’s magnetosheath and polar cusp regions.It uses a high-precision ultraviolet imager to image the overall configuration of the aurora and monitor changes in the source of solar wind in real time,using in situ detection instruments to improve human understanding of the relationship between solar activity and changes in the Earth’s magnetic field.The SMILE satellite is scheduled to launch in 2025.The European Incoherent Scatter Sciences Association(EISCAT)-3D radar is a new generation of European incoherent scatter radar constructed by EISCAT and is the most advanced ground-based ionospheric experimental device in the high-latitude polar region.It has multibeam and multidirectional quasi-real-time three-dimensional(3D)imaging capabilities,continuous monitoring and operation capabilities,and multiple-baseline interferometry capabilities.Joint detection by the SMILE satellite and the EISCAT-3D radar is of great significance for revealing the coupling process of the solar wind–magnetosphere–ionosphere.Therefore,we performed an analysis of the joint detection capability of the SMILE satellite and EISCAT-3D,analyzed the period during which the two can perform joint detection,and defined the key scientific problems that can be solved by joint detection.In addition,we developed Web-based software to search for and visualize the joint detection period of the SMILE satellite and EISCAT-3D radar,which lays the foundation for subsequent joint detection experiments and scientific research. 展开更多
关键词 Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite European Incoherent Scatter Sciences Association(EISCAT)-3D radar joint detection
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Rail-Pillar Net:A 3D Detection Network for Railway Foreign Object Based on LiDAR
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作者 Fan Li Shuyao Zhang +2 位作者 Jie Yang Zhicheng Feng Zhichao Chen 《Computers, Materials & Continua》 SCIE EI 2024年第9期3819-3833,共15页
Aiming at the limitations of the existing railway foreign object detection methods based on two-dimensional(2D)images,such as short detection distance,strong influence of environment and lack of distance information,w... Aiming at the limitations of the existing railway foreign object detection methods based on two-dimensional(2D)images,such as short detection distance,strong influence of environment and lack of distance information,we propose Rail-PillarNet,a three-dimensional(3D)LIDAR(Light Detection and Ranging)railway foreign object detection method based on the improvement of PointPillars.Firstly,the parallel attention pillar encoder(PAPE)is designed to fully extract the features of the pillars and alleviate the problem of local fine-grained information loss in PointPillars pillars encoder.Secondly,a fine backbone network is designed to improve the feature extraction capability of the network by combining the coding characteristics of LIDAR point cloud feature and residual structure.Finally,the initial weight parameters of the model were optimised by the transfer learning training method to further improve accuracy.The experimental results on the OSDaR23 dataset show that the average accuracy of Rail-PillarNet reaches 58.51%,which is higher than most mainstream models,and the number of parameters is 5.49 M.Compared with PointPillars,the accuracy of each target is improved by 10.94%,3.53%,16.96%and 19.90%,respectively,and the number of parameters only increases by 0.64M,which achieves a balance between the number of parameters and accuracy. 展开更多
关键词 Railway foreign object light detection and ranging(LiDAR) 3D object detection PointPillars parallel attention mechanism transfer learning
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Depth-Guided Vision Transformer With Normalizing Flows for Monocular 3D Object Detection
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作者 Cong Pan Junran Peng Zhaoxiang Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期673-689,共17页
Monocular 3D object detection is challenging due to the lack of accurate depth information.Some methods estimate the pixel-wise depth maps from off-the-shelf depth estimators and then use them as an additional input t... Monocular 3D object detection is challenging due to the lack of accurate depth information.Some methods estimate the pixel-wise depth maps from off-the-shelf depth estimators and then use them as an additional input to augment the RGB images.Depth-based methods attempt to convert estimated depth maps to pseudo-LiDAR and then use LiDAR-based object detectors or focus on the perspective of image and depth fusion learning.However,they demonstrate limited performance and efficiency as a result of depth inaccuracy and complex fusion mode with convolutions.Different from these approaches,our proposed depth-guided vision transformer with a normalizing flows(NF-DVT)network uses normalizing flows to build priors in depth maps to achieve more accurate depth information.Then we develop a novel Swin-Transformer-based backbone with a fusion module to process RGB image patches and depth map patches with two separate branches and fuse them using cross-attention to exchange information with each other.Furthermore,with the help of pixel-wise relative depth values in depth maps,we develop new relative position embeddings in the cross-attention mechanism to capture more accurate sequence ordering of input tokens.Our method is the first Swin-Transformer-based backbone architecture for monocular 3D object detection.The experimental results on the KITTI and the challenging Waymo Open datasets show the effectiveness of our proposed method and superior performance over previous counterparts. 展开更多
关键词 Monocular 3D object detection normalizing flows Swin Transformer
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Surface Defect Detection and Evaluation Method of Large Wind Turbine Blades Based on an Improved Deeplabv3+Deep Learning Model
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作者 Wanrun Li Wenhai Zhao +1 位作者 Tongtong Wang Yongfeng Du 《Structural Durability & Health Monitoring》 EI 2024年第5期553-575,共23页
The accumulation of defects on wind turbine blade surfaces can lead to irreversible damage,impacting the aero-dynamic performance of the blades.To address the challenge of detecting and quantifying surface defects on ... The accumulation of defects on wind turbine blade surfaces can lead to irreversible damage,impacting the aero-dynamic performance of the blades.To address the challenge of detecting and quantifying surface defects on wind turbine blades,a blade surface defect detection and quantification method based on an improved Deeplabv3+deep learning model is proposed.Firstly,an improved method for wind turbine blade surface defect detection,utilizing Mobilenetv2 as the backbone feature extraction network,is proposed based on an original Deeplabv3+deep learning model to address the issue of limited robustness.Secondly,through integrating the concept of pre-trained weights from transfer learning and implementing a freeze training strategy,significant improvements have been made to enhance both the training speed and model training accuracy of this deep learning model.Finally,based on segmented blade surface defect images,a method for quantifying blade defects is proposed.This method combines image stitching algorithms to achieve overall quantification and risk assessment of the entire blade.Test results show that the improved Deeplabv3+deep learning model reduces training time by approximately 43.03%compared to the original model,while achieving mAP and MIoU values of 96.87%and 96.93%,respectively.Moreover,it demonstrates robustness in detecting different surface defects on blades across different back-grounds.The application of a blade surface defect quantification method enables the precise quantification of dif-ferent defects and facilitates the assessment of risk levels associated with defect measurements across the entire blade.This method enables non-contact,long-distance,high-precision detection and quantification of surface defects on the blades,providing a reference for assessing surface defects on wind turbine blades. 展开更多
关键词 Structural health monitoring computer vision blade surface defects detection Deeplabv3+ deep learning model
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Genetic Variation Analysis of 3D Gene and Molecular Detection of Porcine Kobuvirus in 2013-2014
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作者 倪艳秀 何孔旺 +10 位作者 茅爱华 俞正玉 李彬 郭容利 吕立新 祝昊丹 周俊明 温立斌 张雪寒 王小敏 汪伟 《Agricultural Science & Technology》 CAS 2015年第3期442-446,共5页
[Objective] This study aimed to investigate the prevalence and variation of porcine kobuvirus (PKV) in suckling piglets in China. [Method] In 2013-2014, 224 feces samples from suckling piglets with diarrhea in 27 pi... [Objective] This study aimed to investigate the prevalence and variation of porcine kobuvirus (PKV) in suckling piglets in China. [Method] In 2013-2014, 224 feces samples from suckling piglets with diarrhea in 27 pig farms of five provinces in China were collected to detect 3D genes of PKV with RT-PCR method; the sequences and genetic variation of 29 PKV 3D genes were analyzed. [Result] Total positive rate of PKV in feces samples from suckling piglets with diarrhea was 65.18% (146/224); total positive rate of PKV in pig farms was 85,2% (23/27); nucleotide sequences and the deduced amino acid sequences of 29 PKV 3D genes shared 87.0%-100% and 92.7%-100% homologies with six PKV-related 3D sequences, respectively. [Conclusion] PKV infection is prevalent in suckling piglets in China; PKV 3D genes exhibit high diversity. 展开更多
关键词 Porcine kobuvirus Molecular detection 3D gene Genetic variation analysis
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GRAPH GRAMMAR METHOD FOR 3-D CORNER DETECTION
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作者 关卓威 张晔 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第3期289-293,共5页
Most of local feature descriptors assume that the scene is planar. In the real scene, the captured images come from the 3-D world. 3-D corner as a novel invariant feature is important for the image matching and the ob... Most of local feature descriptors assume that the scene is planar. In the real scene, the captured images come from the 3-D world. 3-D corner as a novel invariant feature is important for the image matching and the object detection, while automatically discriminating 3-D corners from ordinary corners is difficult. A novel method for 3-D corner detection is proposed based on the image graph grammar, and it can detect the 3-D features of corners to some extent. Experimental results show that the method is valid and the 3-D corner is useful for image matching. 展开更多
关键词 graph grammar 3-D corner detection production rule
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Flexible Tactile Electronic Skin Sensor with 3D Force Detection Based on Porous CNTs/PDMS Nanocomposites 被引量:21
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作者 Xuguang Sun Jianhai Sun +9 位作者 Tong Li Shuaikang Zheng Chunkai Wang Wenshuo Tan Jingong Zhang Chang Liu Tianjun Ma Zhimei Qi Chunxiu Liu Ning Xue 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第4期35-48,共14页
Flexible tactile sensors have broad applications in human physiological monitoring,robotic operation and human-machine interaction.However,the research of wearable and flexible tactile sensors with high sensitivity,wi... Flexible tactile sensors have broad applications in human physiological monitoring,robotic operation and human-machine interaction.However,the research of wearable and flexible tactile sensors with high sensitivity,wide sensing range and ability to detect three-dimensional(3D)force is still very challenging.Herein,a flexible tactile electronic skin sensor based on carbon nanotubes(CNTs)/polydimethylsiloxane(PDMS)nanocomposites is presented for 3D contact force detection.The 3D forces were acquired from combination of four specially designed cells in a sensing element.Contributed from the double-sided rough porous structure and specific surface morphology of nanocomposites,the piezoresistive sensor possesses high sensitivity of 12.1 kPa?1 within the range of 600 Pa and 0.68 kPa?1 in the regime exceeding 1 kPa for normal pressure,as well as 59.9 N?1 in the scope of<0.05 N and>2.3 N?1 in the region of<0.6 N for tangential force with ultra-low response time of 3.1 ms.In addition,multi-functional detection in human body monitoring was employed with single sensing cell and the sensor array was integrated into a robotic arm for objects grasping control,indicating the capacities in intelligent robot applications. 展开更多
关键词 Flexible TACTILE sensors ELECTRONIC SKIN Piezoresistive sensors CNTs/PDMS NANOCOMPOSITES 3D force detection
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In^(3+)、Sb^(3+)、Bi^(3+)掺杂对双钙钛矿Cs_(2)NaDyCl_(6)发光性能的调控
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作者 周宇 王有力 《半导体技术》 CAS 北大核心 2024年第6期538-543,共6页
A2B′BCl_(6)型双钙钛矿因其极强的空气稳定性和出色的光学性能而被应用于发光材料。使用Na离子替代式掺杂合成非铅体系钙钛矿材料Cs_(2)NaDyCl_(6),引入In^(3+)、Sb^(3+)和Bi^(3+)等掺杂元素对双钙钛矿Cs_(2)NaDyCl_(6)发光性能进行调... A2B′BCl_(6)型双钙钛矿因其极强的空气稳定性和出色的光学性能而被应用于发光材料。使用Na离子替代式掺杂合成非铅体系钙钛矿材料Cs_(2)NaDyCl_(6),引入In^(3+)、Sb^(3+)和Bi^(3+)等掺杂元素对双钙钛矿Cs_(2)NaDyCl_(6)发光性能进行调控。结果表明:通过In^(3+)的掺杂,拓宽了材料的发射区间,进一步提高了其光学性能;Bi^(3+)掺杂能够使钙钛矿的发射光发生红移现象,Sb^(3+)掺杂可以使钙钛矿的发射光发生蓝移现象,Sb^(3+)和Bi^(3+)共同掺杂能够平衡钙钛矿在可见光区域的发射;在In^(3+)、Sb^(3+)、Bi^(3+)三种元素的共同掺杂下,Cs_(2)NaDy_(0.445)In_(0.445)Cl_(6)∶0.1Bi 0.01Sb成功实现了白光发射,在265 nm波长激发下,其CIE色坐标为(0.34,0.35),色温达到5314 K,显色指数高达94。 展开更多
关键词 双钙钛矿 掺杂 发光性能 In^(3+) Sb^(3+) Bi^(3+)
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3D cavity detection technique and its application based on cavity auto scanning laser system 被引量:3
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作者 刘希灵 李夕兵 +2 位作者 李发本 赵国彦 秦豫辉 《Journal of Central South University of Technology》 EI 2008年第2期285-288,共4页
Ground constructions and mines are severely threatened by ones. Safe and precise cavity detection is vital for reasonable cavity underground cavities especially those unsafe or inaccessible evaluation and disposal. Th... Ground constructions and mines are severely threatened by ones. Safe and precise cavity detection is vital for reasonable cavity underground cavities especially those unsafe or inaccessible evaluation and disposal. The conventional cavity detection methods and their limitation were analyzed. Those methods cannot form 3D model of underground cavity which is used for instructing the cavity disposal; and their precisions in detection are always greatly affected by the geological circumstance. The importance of 3D cavity detection in metal mine for safe exploitation was pointed out; and the 3D cavity laser detection method and its principle were introduced. A cavity auto scanning laser system was recommended to actualize the cavity 3D detection after comparing with the other laser detection systems. Four boreholes were chosen to verify the validity of the cavity auto scanning laser system. The results show that the cavity auto scanning laser system is very suitable for underground 3D cavity detection, especially for those inaccessible ones. 展开更多
关键词 cavity detection 3D laser detection cavity auto scanning laser system
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Heterogeneous Cu_(x)O Nano‑Skeletons from Waste Electronics for Enhanced Glucose Detection
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作者 Yexin Pan Ruohan Yu +8 位作者 Yalong Jiang Haosong Zhong Qiaoyaxiao Yuan Connie Kong Wai Lee Rongliang Yang Siyu Chen Yi Chen Wing Yan Poon Mitch Guijun Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期554-568,共15页
Electronic waste(e-waste)and diabetes are global challenges to modern societies.However,solving these two challenges together has been challenging until now.Herein,we propose a laser-induced transfer method to fabrica... Electronic waste(e-waste)and diabetes are global challenges to modern societies.However,solving these two challenges together has been challenging until now.Herein,we propose a laser-induced transfer method to fabricate portable glucose sensors by recycling copper from e-waste.We bring up a laser-induced full-automatic fabrication method for synthesizing continuous heterogeneous Cu_(x)O(h-Cu_(x)O)nano-skeletons electrode for glucose sensing,offering rapid(<1 min),clean,air-compatible,and continuous fabrication,applicable to a wide range of Cu-containing substrates.Leveraging this approach,h-Cu_(x)O nanoskeletons,with an inner core predominantly composed of Cu_(2)O with lower oxygen content,juxtaposed with an outer layer rich in amorphous Cu_(x)O(a-Cu_(x)O)with higher oxygen content,are derived from discarded printed circuit boards.When employed in glucose detection,the h-Cu_(x)O nano-skeletons undergo a structural evolution process,transitioning into rigid Cu_(2)O@CuO nano-skeletons prompted by electrochemical activation.This transformation yields exceptional glucose-sensing performance(sensitivity:9.893 mA mM^(-1) cm^(-2);detection limit:0.34μM),outperforming most previously reported glucose sensors.Density functional theory analysis elucidates that the heterogeneous structure facilitates gluconolactone desorption.This glucose detection device has also been downsized to optimize its scalability and portability for convenient integration into people’s everyday lives. 展开更多
关键词 Copper oxide Electron 3D tomography E-WASTE Glucose detection Electrochemical activation
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Correg-Yolov3:a Method for Dense Buildings Detection in High-resolution Remote Sensing Images 被引量:5
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作者 Zhanlong CHEN Shuangjiang LI +3 位作者 Yongyang XU Daozhu XU Chao MA Junli ZHAO 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第2期51-61,共11页
The exploration of building detection plays an important role in urban planning,smart city and military.Aiming at the problem of high overlapping ratio of detection frames for dense building detection in high resoluti... The exploration of building detection plays an important role in urban planning,smart city and military.Aiming at the problem of high overlapping ratio of detection frames for dense building detection in high resolution remote sensing images,we present an effective YOLOv3 framework,corner regression-based YOLOv3(Correg-YOLOv3),to localize dense building accurately.This improved YOLOv3 algorithm establishes a vertex regression mechanism and an additional loss item about building vertex offsets relative to the center point of bounding box.By extending output dimensions,the trained model is able to output the rectangular bounding boxes and the building vertices meanwhile.Finally,we evaluate the performance of the Correg-YOLOv3 on our self-produced data set and provide a comparative analysis qualitatively and quantitatively.The experimental results achieve high performance in precision(96.45%),recall rate(95.75%),F1 score(96.10%)and average precision(98.05%),which were 2.73%,5.4%,4.1%and 4.73%higher than that of YOLOv3.Therefore,our proposed algorithm effectively tackles the problem of dense building detection in high resolution images. 展开更多
关键词 high resolution remote sensing image Correg-YOLOv3 corner regression dense buildings object detection
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Mural Anomaly Region Detection Algorithm Based on Hyperspectral Multiscale Residual Attention Network
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作者 Bolin Guo Shi Qiu +1 位作者 Pengchang Zhang Xingjia Tang 《Computers, Materials & Continua》 SCIE EI 2024年第10期1809-1833,共25页
Mural paintings hold significant historical information and possess substantial artistic and cultural value.However,murals are inevitably damaged by natural environmental factors such as wind and sunlight,as well as b... Mural paintings hold significant historical information and possess substantial artistic and cultural value.However,murals are inevitably damaged by natural environmental factors such as wind and sunlight,as well as by human activities.For this reason,the study of damaged areas is crucial for mural restoration.These damaged regions differ significantly from undamaged areas and can be considered abnormal targets.Traditional manual visual processing lacks strong characterization capabilities and is prone to omissions and false detections.Hyperspectral imaging can reflect the material properties more effectively than visual characterization methods.Thus,this study employs hyperspectral imaging to obtain mural information and proposes a mural anomaly detection algorithm based on a hyperspectral multi-scale residual attention network(HM-MRANet).The innovations of this paper include:(1)Constructing mural painting hyperspectral datasets.(2)Proposing a multi-scale residual spectral-spatial feature extraction module based on a 3D CNN(Convolutional Neural Networks)network to better capture multiscale information and improve performance on small-sample hyperspectral datasets.(3)Proposing the Enhanced Residual Attention Module(ERAM)to address the feature redundancy problem,enhance the network’s feature discrimination ability,and further improve abnormal area detection accuracy.The experimental results show that the AUC(Area Under Curve),Specificity,and Accuracy of this paper’s algorithm reach 85.42%,88.84%,and 87.65%,respectively,on this dataset.These results represent improvements of 3.07%,1.11%and 2.68%compared to the SSRN algorithm,demonstrating the effectiveness of this method for mural anomaly detection. 展开更多
关键词 MURALS anomaly detection HYPERSPECTRAL 3D CNN(Convolutional Neural Networks) residual network
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植物补光用In^(3+)掺杂Zn_(3)Ga_(2)Ge_(2)O_(10)∶Cr^(3+)远红光发光材料的性能研究
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作者 白琼宇 王春浩 《人工晶体学报》 CAS 北大核心 2024年第9期1568-1575,共8页
采用高温固相法制备了Cr^(3+)掺杂的远红光荧光粉,并通过引入In^(3+)对Zn_(3)Ga_(2)Ge_(2)O_(10)∶Cr^(3+)发光特性进行了调控。通过XRD对Zn_(3)(Ga_(1-x)In_(x))_(2)Ge_(2)O_(10)∶2%Cr^(3+)(摩尔分数)的晶体结构进行了分析。利用室温... 采用高温固相法制备了Cr^(3+)掺杂的远红光荧光粉,并通过引入In^(3+)对Zn_(3)Ga_(2)Ge_(2)O_(10)∶Cr^(3+)发光特性进行了调控。通过XRD对Zn_(3)(Ga_(1-x)In_(x))_(2)Ge_(2)O_(10)∶2%Cr^(3+)(摩尔分数)的晶体结构进行了分析。利用室温荧光光谱和热释光光谱分析了Zn_(3)(Ga_(1-x)In_(x))_(2)Ge_(2)O_(10)∶2%Cr^(3+)的发光特性,其发射光谱由^(4)T_(2)(^(4)F)→^(4)A_(2)和^(2)E→^(4)A_(2)跃迁的705、721 nm两发光峰叠加而成。随着Zn_(3)(Ga_(1-x)In_(x))_(2)Ge_(2)O_(10)∶2%Cr^(3+)中In^(3+)掺杂浓度增加,材料发射光谱呈现展宽的现象,这是Cr^(3+)所处晶体场环境的改变导致了晶体场劈裂程度的变化。光谱展宽后荧光材料的发光特性与植物中光敏色素吸收谱更加匹配,因此其有望应用于植物照明领域。此外,随着In^(3+)掺杂浓度增加,荧光材料表现出红色长余辉现象,并且余辉时间与In^(3+)掺杂浓度有关。 展开更多
关键词 荧光粉 Zn_(3)Ga_(2)Ge_(2)O_(10)∶Cr^(3+) In^(3+)掺杂 远红光 阳离子替代 植物补光
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A highly sensitive ratiometric near-infrared nanosensor based on erbium-hyperdoped silicon quantum dots for iron(Ⅲ) detection
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作者 Kun Wang Wenxuan Lai +2 位作者 Zhenyi Ni Deren Yang Xiaodong Pi 《Journal of Semiconductors》 EI CAS CSCD 2024年第8期49-58,共10页
Ratiometric fluorescent detection of iron(Ⅲ)(Fe^(3+))offers inherent self-calibration and contactless analytic capabilities.However,realizing a dual-emission near-infrared(NIR)nanosensor with a low limit of detection... Ratiometric fluorescent detection of iron(Ⅲ)(Fe^(3+))offers inherent self-calibration and contactless analytic capabilities.However,realizing a dual-emission near-infrared(NIR)nanosensor with a low limit of detection(LOD)is rather challenging.In this work,we report the synthesis of water-dispersible erbium-hyperdoped silicon quantum dots(Si QDs:Er),which emit NIR light at the wavelengths of 810 and 1540 nm.A dual-emission NIR nanosensor based on water-dispersible Si QDs:Er enables ratiometric Fe^(3+)detection with a very low LOD(0.06μM).The effects of pH,recyclability,and the interplay between static and dynamic quenching mechanisms for Fe^(3+)detection have been systematically studied.In addition,we demonstrate that the nanosensor may be used to construct a sequential logic circuit with memory functions. 展开更多
关键词 erbium-hyperdoped silicon quantum dots dual-emission near-infrared nanosensor Fe^(3+)detection sequential logic circuit
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A new approach for salt dome detection using a 3D multidirectional edge detector 被引量:1
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作者 Asjad Amin Mohamed Deriche 《Applied Geophysics》 SCIE CSCD 2015年第3期334-342,466,467,共11页
Accurate salt dome detection from 3D seismic data is crucial to different seismic data analysis applications. We present a new edge based approach for salt dome detection in migrated 3D seismic data. The proposed algo... Accurate salt dome detection from 3D seismic data is crucial to different seismic data analysis applications. We present a new edge based approach for salt dome detection in migrated 3D seismic data. The proposed algorithm overcomes the drawbacks of existing edge-based techniques which only consider edges in the x (crossline) and y (inline) directions in 2D data and the x (crossline), y (inline), and z (time) directions in 3D data. The algorithm works by combining 3D gradient maps computed along diagonal directions and those computed in x, y, and z directions to accurately detect the boundaries of salt regions. The combination of x, y, and z directions and diagonal edges ensures that the proposed algorithm works well even if the dips along the salt boundary are represented only by weak reflectors. Contrary to other edge and texture based salt dome detection techniques, the proposed algorithm is independent of the amplitude variations in seismic data. We tested the proposed algorithm on the publicly available Netherlands offshore F3 block. The results suggest that the proposed algorithm can detect salt bodies with high accuracy than existing gradient based and texture-based techniques when used separately. More importantly, the proposed approach is shown to be computationally efficient allowing for real time implementation and deployment. 展开更多
关键词 Salt dome seismic interpretation 3D edge detection 3D Sobel multidirectionaledge detector
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Preparation of polythiophene/WO_3 organic-inorganic hybrids and their gas sensing properties for NO_2 detection at low temperature 被引量:2
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作者 Jing Huan~ Yanfei Kang +2 位作者 Taili Yang Yao Wang Shurong Wang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第4期403-407,共5页
Polythiophene/WO3(PTP/WO3)organic-inorganic hybrids were synthesized by an in situ chemical oxidative polymerization method,and char- acterized by X-ray diffraction(XRD),transmission electron microscopy(TEM)and ... Polythiophene/WO3(PTP/WO3)organic-inorganic hybrids were synthesized by an in situ chemical oxidative polymerization method,and char- acterized by X-ray diffraction(XRD),transmission electron microscopy(TEM)and thermo-gravimetric analysis(TGA).The Polythiophene/ WO3 hybrids have higher thermal stability than pure polythiophene,which is beneficial to potential application as chemical sensors.Gas sensing measurements demonstrate that the gas sensor based on the Polythiophene/WO3 hybrids has high response and good selectivity for de- tecting NO2 of ppm level at low temperature.Both the operating temperature and PTP contents have an influence on the response of PTP/WO3 hybrids to NO2.The 10 wt%PTP/WO3 hybrid showed the highest response at low operating temperature of 70-C.It is expected that the PTP/WO3 hybrids can be potentially used as gas sensor material for detecting the low concentration of NO2 at low temperature. 展开更多
关键词 polythiophene/WO3 organic-inorganic hybrids gas sensing properties NO2 detection low temperature
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Contemporary Study for Detection of COVID-19 Using Machine Learning with Explainable AI
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作者 Saad Akbar Humera Azam +3 位作者 Sulaiman Sulmi Almutairi Omar Alqahtani Habib Shah Aliya Aleryani 《Computers, Materials & Continua》 SCIE EI 2024年第7期1075-1104,共30页
The prompt spread of COVID-19 has emphasized the necessity for effective and precise diagnostic tools.In this article,a hybrid approach in terms of datasets as well as the methodology by utilizing a previously unexplo... The prompt spread of COVID-19 has emphasized the necessity for effective and precise diagnostic tools.In this article,a hybrid approach in terms of datasets as well as the methodology by utilizing a previously unexplored dataset obtained from a private hospital for detecting COVID-19,pneumonia,and normal conditions in chest X-ray images(CXIs)is proposed coupled with Explainable Artificial Intelligence(XAI).Our study leverages less preprocessing with pre-trained cutting-edge models like InceptionV3,VGG16,and VGG19 that excel in the task of feature extraction.The methodology is further enhanced by the inclusion of the t-SNE(t-Distributed Stochastic Neighbor Embedding)technique for visualizing the extracted image features and Contrast Limited Adaptive Histogram Equalization(CLAHE)to improve images before extraction of features.Additionally,an AttentionMechanism is utilized,which helps clarify how the modelmakes decisions,which builds trust in artificial intelligence(AI)systems.To evaluate the effectiveness of the proposed approach,both benchmark datasets and a private dataset obtained with permissions from Jinnah PostgraduateMedical Center(JPMC)in Karachi,Pakistan,are utilized.In 12 experiments,VGG19 showcased remarkable performance in the hybrid dataset approach,achieving 100%accuracy in COVID-19 vs.pneumonia classification and 97%in distinguishing normal cases.Overall,across all classes,the approach achieved 98%accuracy,demonstrating its efficiency in detecting COVID-19 and differentiating it fromother chest disorders(Pneumonia and healthy)while also providing insights into the decision-making process of the models. 展开更多
关键词 COVID-19 detection deep neural networks support vector machine CXIs InceptionV3 VGG16 VGG19 t-SNE embedding CLAHE attention mechanism XAI
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Nature-Inspired Level Set Segmentation Model for 3D-MRI Brain Tumor Detection 被引量:1
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作者 Oday Ali Hassen Sarmad Omar Abter +3 位作者 Ansam A.Abdulhussein Saad M.Darwish Yasmine M.Ibrahim Walaa Sheta 《Computers, Materials & Continua》 SCIE EI 2021年第7期961-981,共21页
Medical image segmentation has consistently been a significant topic of research and a prominent goal,particularly in computer vision.Brain tumor research plays a major role in medical imaging applications by providin... Medical image segmentation has consistently been a significant topic of research and a prominent goal,particularly in computer vision.Brain tumor research plays a major role in medical imaging applications by providing a tremendous amount of anatomical and functional knowledge that enhances and allows easy diagnosis and disease therapy preparation.To prevent or minimize manual segmentation error,automated tumor segmentation,and detection became the most demanding process for radiologists and physicians as the tumor often has complex structures.Many methods for detection and segmentation presently exist,but all lack high accuracy.This paper’s key contribution focuses on evaluating machine learning techniques that are supposed to reduce the effect of frequently found issues in brain tumor research.Furthermore,attention concentrated on the challenges related to level set segmentation.The study proposed in this paper uses the Population-based Artificial Bee Colony Clustering(P-ABCC)methodology to reliably collect initial contour points,which helps minimize the number of iterations and segmentation errors of the level-set process.The proposed model measures cluster centroids(ABC populations)and uses a level-set approach to resolve contour differences as brain tumors vary as they have irregular form,structure,and volume.The suggested model comprises of three major steps:first,pre-processing to separate the brain from the head and improves contrast stretching.Secondly,P-ABCC is used to obtain tumor edges that are utilized as an initial MRI sequence contour.The level-set segmentation is then used to detect tumor regions from all volume slices with fewer iterations.Results suggest improved model efficiency compared to state-of-the-art methods for both datasets BRATS 2019 and BRATS 2017.At BRATS 2019,dice progress was achieved for Entire Tumor(WT),Tumor Center(TC),and Improved Tumor(ET)by 0.03%,0.03%,and 0.01%respectively.At BRATS 2017,an increase in precision for WT was reached by 5.27%. 展开更多
关键词 3D-MRI tumor diagnosis bio-inspired clustering ABC optimization multimodal detection
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A Lightweight Driver Drowsiness Detection System Using 3DCNN With LSTM 被引量:1
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作者 Sara A.Alameen Areej M.Alhothali 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期895-912,共18页
Today,fatalities,physical injuries,and significant economic losses occur due to car accidents.Among the leading causes of car accidents is drowsiness behind the wheel,which can affect any driver.Drowsiness and sleepin... Today,fatalities,physical injuries,and significant economic losses occur due to car accidents.Among the leading causes of car accidents is drowsiness behind the wheel,which can affect any driver.Drowsiness and sleepiness often have associated indicators that researchers can use to identify and promptly warn drowsy drivers to avoid potential accidents.This paper proposes a spatiotemporal model for monitoring drowsiness visual indicators from videos.This model depends on integrating a 3D convolutional neural network(3D-CNN)and long short-term memory(LSTM).The 3DCNN-LSTM can analyze long sequences by applying the 3D-CNN to extract spatiotemporal features within adjacent frames.The learned features are then used as the input of the LSTM component for modeling high-level temporal features.In addition,we investigate how the training of the proposed model can be affected by changing the position of the batch normalization(BN)layers in the 3D-CNN units.The BN layer is examined in two different placement settings:before the non-linear activation function and after the non-linear activation function.The study was conducted on two publicly available drowsy drivers datasets named 3MDAD and YawDD.3MDAD is mainly composed of two synchronized datasets recorded from the frontal and side views of the drivers.We show that the position of the BN layers increases the convergence speed and reduces overfitting on one dataset but not the other.As a result,the model achieves a test detection accuracy of 96%,93%,and 90%on YawDD,Side-3MDAD,and Front-3MDAD,respectively. 展开更多
关键词 3D-CNN deep learning driver drowsiness detection LSTM spatiotemporal features
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Assimilation of FY-3D MWTS-Ⅱ Radiance with 3D Precipitation Detection and the Impacts on Typhoon Forecasts 被引量:1
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作者 Luyao QIN Yaodeng CHEN +3 位作者 Gang MA Fuzhong WENG Deming MENG Peng ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第5期900-919,共20页
Precipitation detection is an essential step in radiance assimilation because the uncertainties in precipitation would affect the radiative transfer calculation and observation errors.The traditional precipitation det... Precipitation detection is an essential step in radiance assimilation because the uncertainties in precipitation would affect the radiative transfer calculation and observation errors.The traditional precipitation detection method for microwave only detects clouds and precipitation horizontally,without considering the three-dimensional distribution of clouds.Extending precipitation detection from 2D to 3D is expected to bring more useful information to the data assimilation without using the all-sky approach.In this study,the 3D precipitation detection method is adopted to assimilate Microwave Temperature Sounder-2(MWTS-Ⅱ)onboard the Fengyun-3D,which can dynamically detect the channels above precipitating clouds by considering the near-real-time cloud parameters.Cycling data assimilation and forecasting experiments for Typhoons Lekima(2019)and Mitag(2019)are carried out.Compared with the control experiment,the quantity of assimilated data with the 3D precipitation detection increases by approximately 23%.The quality of the additional MWTS-Ⅱradiance data is close to the clear-sky data.The case studies show that the average root-mean-square errors(RMSE)of prognostic variables are reduced by 1.7%in the upper troposphere,leading to an average reduction of4.53%in typhoon track forecasts.The detailed diagnoses of Typhoon Lekima(2019)further show that the additional MWTS-Ⅱradiances brought by the 3D precipitation detection facilitate portraying a more reasonable circulation situation,thus providing more precise structures.This paper preliminarily proves that 3D precipitation detection has potential added value for increasing satellite data utilization and improving typhoon forecasts. 展开更多
关键词 numerical weather prediction radiance assimilation microwave temperature sounding FY-3D MWTS-II precipitation detection
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