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Multi-Scale Mixed Attention Tea Shoot Instance Segmentation Model
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作者 Dongmei Chen Peipei Cao +5 位作者 Lijie Yan Huidong Chen Jia Lin Xin Li Lin Yuan Kaihua Wu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期261-275,共15页
Tea leaf picking is a crucial stage in tea production that directly influences the quality and value of the tea.Traditional tea-picking machines may compromise the quality of the tea leaves.High-quality teas are often... Tea leaf picking is a crucial stage in tea production that directly influences the quality and value of the tea.Traditional tea-picking machines may compromise the quality of the tea leaves.High-quality teas are often handpicked and need more delicate operations in intelligent picking machines.Compared with traditional image processing techniques,deep learning models have stronger feature extraction capabilities,and better generalization and are more suitable for practical tea shoot harvesting.However,current research mostly focuses on shoot detection and cannot directly accomplish end-to-end shoot segmentation tasks.We propose a tea shoot instance segmentation model based on multi-scale mixed attention(Mask2FusionNet)using a dataset from the tea garden in Hangzhou.We further analyzed the characteristics of the tea shoot dataset,where the proportion of small to medium-sized targets is 89.9%.Our algorithm is compared with several mainstream object segmentation algorithms,and the results demonstrate that our model achieves an accuracy of 82%in recognizing the tea shoots,showing a better performance compared to other models.Through ablation experiments,we found that ResNet50,PointRend strategy,and the Feature Pyramid Network(FPN)architecture can improve performance by 1.6%,1.4%,and 2.4%,respectively.These experiments demonstrated that our proposed multi-scale and point selection strategy optimizes the feature extraction capability for overlapping small targets.The results indicate that the proposed Mask2FusionNet model can perform the shoot segmentation in unstructured environments,realizing the individual distinction of tea shoots,and complete extraction of the shoot edge contours with a segmentation accuracy of 82.0%.The research results can provide algorithmic support for the segmentation and intelligent harvesting of premium tea shoots at different scales. 展开更多
关键词 Tea shoots attention mechanism multi-scale feature extraction instance segmentation deep learning
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Two Stages Segmentation Algorithm of Breast Tumor in DCE-MRI Based on Multi-Scale Feature and Boundary Attention Mechanism
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作者 Bing Li Liangyu Wang +3 位作者 Xia Liu Hongbin Fan Bo Wang Shoudi Tong 《Computers, Materials & Continua》 SCIE EI 2024年第7期1543-1561,共19页
Nuclearmagnetic resonance imaging of breasts often presents complex backgrounds.Breast tumors exhibit varying sizes,uneven intensity,and indistinct boundaries.These characteristics can lead to challenges such as low a... Nuclearmagnetic resonance imaging of breasts often presents complex backgrounds.Breast tumors exhibit varying sizes,uneven intensity,and indistinct boundaries.These characteristics can lead to challenges such as low accuracy and incorrect segmentation during tumor segmentation.Thus,we propose a two-stage breast tumor segmentation method leveraging multi-scale features and boundary attention mechanisms.Initially,the breast region of interest is extracted to isolate the breast area from surrounding tissues and organs.Subsequently,we devise a fusion network incorporatingmulti-scale features and boundary attentionmechanisms for breast tumor segmentation.We incorporate multi-scale parallel dilated convolution modules into the network,enhancing its capability to segment tumors of various sizes through multi-scale convolution and novel fusion techniques.Additionally,attention and boundary detection modules are included to augment the network’s capacity to locate tumors by capturing nonlocal dependencies in both spatial and channel domains.Furthermore,a hybrid loss function with boundary weight is employed to address sample class imbalance issues and enhance the network’s boundary maintenance capability through additional loss.Themethod was evaluated using breast data from 207 patients at RuijinHospital,resulting in a 6.64%increase in Dice similarity coefficient compared to the benchmarkU-Net.Experimental results demonstrate the superiority of the method over other segmentation techniques,with fewer model parameters. 展开更多
关键词 Dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) breast tumor segmentation multi-scale dilated convolution boundary attention the hybrid loss function with boundary weight
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Colorectal Cancer Segmentation Algorithm Based on Deep Features from Enhanced CT Images
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作者 Shi Qiu Hongbing Lu +2 位作者 Jun Shu Ting Liang Tao Zhou 《Computers, Materials & Continua》 SCIE EI 2024年第8期2495-2510,共16页
Colorectal cancer,a malignant lesion of the intestines,significantly affects human health and life,emphasizing the necessity of early detection and treatment.Accurate segmentation of colorectal cancer regions directly... Colorectal cancer,a malignant lesion of the intestines,significantly affects human health and life,emphasizing the necessity of early detection and treatment.Accurate segmentation of colorectal cancer regions directly impacts subsequent staging,treatment methods,and prognostic outcomes.While colonoscopy is an effective method for detecting colorectal cancer,its data collection approach can cause patient discomfort.To address this,current research utilizes Computed Tomography(CT)imaging;however,conventional CT images only capture transient states,lacking sufficient representational capability to precisely locate colorectal cancer.This study utilizes enhanced CT images,constructing a deep feature network from the arterial,portal venous,and delay phases to simulate the physician’s diagnostic process and achieve accurate cancer segmentation.The innovations include:1)Utilizing portal venous phase CT images to introduce a context-aware multi-scale aggregation module for preliminary shape extraction of colorectal cancer.2)Building an image sequence based on arterial and delay phases,transforming the cancer segmentation issue into an anomaly detection problem,establishing a pixel-pairing strategy,and proposing a colorectal cancer segmentation algorithm using a Siamese network.Experiments with 84 clinical cases of colorectal cancer enhanced CT data demonstrated an Area Overlap Measure of 0.90,significantly better than Fully Convolutional Networks(FCNs)at 0.20.Future research will explore the relationship between conventional and enhanced CT to further reduce segmentation time and improve accuracy. 展开更多
关键词 Colorectal cancer enhanced CT multi-scale siamese network segmentation
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Attention Guided Multi Scale Feature Fusion Network for Automatic Prostate Segmentation
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作者 Yuchun Li Mengxing Huang +1 位作者 Yu Zhang Zhiming Bai 《Computers, Materials & Continua》 SCIE EI 2024年第2期1649-1668,共20页
The precise and automatic segmentation of prostate magnetic resonance imaging(MRI)images is vital for assisting doctors in diagnosing prostate diseases.In recent years,many advanced methods have been applied to prosta... The precise and automatic segmentation of prostate magnetic resonance imaging(MRI)images is vital for assisting doctors in diagnosing prostate diseases.In recent years,many advanced methods have been applied to prostate segmentation,but due to the variability caused by prostate diseases,automatic segmentation of the prostate presents significant challenges.In this paper,we propose an attention-guided multi-scale feature fusion network(AGMSF-Net)to segment prostate MRI images.We propose an attention mechanism for extracting multi-scale features,and introduce a 3D transformer module to enhance global feature representation by adding it during the transition phase from encoder to decoder.In the decoder stage,a feature fusion module is proposed to obtain global context information.We evaluate our model on MRI images of the prostate acquired from a local hospital.The relative volume difference(RVD)and dice similarity coefficient(DSC)between the results of automatic prostate segmentation and ground truth were 1.21%and 93.68%,respectively.To quantitatively evaluate prostate volume on MRI,which is of significant clinical significance,we propose a unique AGMSF-Net.The essential performance evaluation and validation experiments have demonstrated the effectiveness of our method in automatic prostate segmentation. 展开更多
关键词 Prostate segmentation multi-scale attention 3D Transformer feature fusion MRI
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An algorithm for segmentation of lung ROI by mean-shift clustering combined with multi-scale HESSIAN matrix dot filtering 被引量:7
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作者 魏颖 李锐 +1 位作者 杨金柱 赵大哲 《Journal of Central South University》 SCIE EI CAS 2012年第12期3500-3509,共10页
A new algorithm for segmentation of suspected lung ROI(regions of interest)by mean-shift clustering and multi-scale HESSIAN matrix dot filtering was proposed.Original image was firstly filtered by multi-scale HESSIAN ... A new algorithm for segmentation of suspected lung ROI(regions of interest)by mean-shift clustering and multi-scale HESSIAN matrix dot filtering was proposed.Original image was firstly filtered by multi-scale HESSIAN matrix dot filters,round suspected nodular lesions in the image were enhanced,and linear shape regions of the trachea and vascular were suppressed.Then,three types of information,such as,shape filtering value of HESSIAN matrix,gray value,and spatial location,were introduced to feature space.The kernel function of mean-shift clustering was divided into product form of three kinds of kernel functions corresponding to the three feature information.Finally,bandwidths were calculated adaptively to determine the bandwidth of each suspected area,and they were used in mean-shift clustering segmentation.Experimental results show that by the introduction of HESSIAN matrix of dot filtering information to mean-shift clustering,nodular regions can be segmented from blood vessels,trachea,or cross regions connected to the nodule,non-nodular areas can be removed from ROIs properly,and ground glass object(GGO)nodular areas can also be segmented.For the experimental data set of 127 different forms of nodules,the average accuracy of the proposed algorithm is more than 90%. 展开更多
关键词 HESSIAN matrix multi-scale dot filtering mean-shift clustering segmentation of suspected areas lung computer-aideddetection/diagnosis
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Watershed segmentation based on hierarchical multi-scale modification of morphological gradient 被引量:1
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作者 WANG Xiao-peng ZHAO Jun-jun +1 位作者 MA Peng YAO Li-juan 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第1期60-67,共8页
Watershed segmentation is sensitive to noises and irregular details within the image,which frequently leads to a serious over-segmentation Linear filtering before watershed segmentation can reduce over-segmentation to... Watershed segmentation is sensitive to noises and irregular details within the image,which frequently leads to a serious over-segmentation Linear filtering before watershed segmentation can reduce over-segmentation to some extent,however,it often causes the position offset of object contours.For the purpose of reducing over-segmentation to preserve the location of object contours,the watershed segmentation based on the hierarchical multi-scale modification of morphological gradient is proposed.Firstly,multi-scale morphological filtering was employed to smooth the original image.Then,the gradient image was divided into multi-levels by the volume of three-dimension topographic relief,where the lower gradient layers were further modifiedby morphological closing with larger-sized structuring-elements,and the higher layers with the smaller one.In this way,most local minimums caused by irregular details and noises can be removed,while region contour positions corresponding to the target area were largely preserved.Finally,morphological watershed algorithm was employed to implement segmentation on the modified gradient image.The experimental results show that the proposed method can greatly reduce the over-segmentation of the watershed and avoid the position offset of the object contours. 展开更多
关键词 watershed segmentation gradient modification hierarchical multi-scale morphological filtering structuring element
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A Multi-Scale Network with the Encoder-Decoder Structure for CMR Segmentation 被引量:1
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作者 Chaoyang Xia Jing Peng +1 位作者 Zongqing Ma Xiaojie Li 《Journal of Information Hiding and Privacy Protection》 2019年第3期109-117,共9页
Cardiomyopathy is one of the most serious public health threats.The precise structural and functional cardiac measurement is an essential step for clinical diagnosis and follow-up treatment planning.Cardiologists are ... Cardiomyopathy is one of the most serious public health threats.The precise structural and functional cardiac measurement is an essential step for clinical diagnosis and follow-up treatment planning.Cardiologists are often required to draw endocardial and epicardial contours of the left ventricle(LV)manually in routine clinical diagnosis or treatment planning period.This task is time-consuming and error-prone.Therefore,it is necessary to develop a fully automated end-to-end semantic segmentation method on cardiac magnetic resonance(CMR)imaging datasets.However,due to the low image quality and the deformation caused by heartbeat,there is no effective tool for fully automated end-to-end cardiac segmentation task.In this work,we propose a multi-scale segmentation network(MSSN)for left ventricle segmentation.It can effectively learn myocardium and blood pool structure representations from 2D short-axis CMR image slices in a multi-scale way.Specifically,our method employs both parallel and serial of dilated convolution layers with different dilation rates to capture multi-scale semantic features.Moreover,we design graduated up-sampling layers with subpixel layers as the decoder to reconstruct lost spatial information and produce accurate segmentation masks.We validated our method using 164 T1 Mapping CMR images and showed that it outperforms the advanced convolutional neural network(CNN)models.In validation metrics,we archived the Dice Similarity Coefficient(DSC)metric of 78.96%. 展开更多
关键词 Cardiac magnetic resonance imaging multi-scale semantic segmentation convolutional neural networks
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DT-Net:Joint Dual-Input Transformer and CNN for Retinal Vessel Segmentation
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作者 Wenran Jia Simin Ma +1 位作者 Peng Geng Yan Sun 《Computers, Materials & Continua》 SCIE EI 2023年第9期3393-3411,共19页
Retinal vessel segmentation in fundus images plays an essential role in the screening,diagnosis,and treatment of many diseases.The acquired fundus images generally have the following problems:uneven illumination,high ... Retinal vessel segmentation in fundus images plays an essential role in the screening,diagnosis,and treatment of many diseases.The acquired fundus images generally have the following problems:uneven illumination,high noise,and complex structure.It makes vessel segmentation very challenging.Previous methods of retinal vascular segmentation mainly use convolutional neural networks on U Network(U-Net)models,and they have many limitations and shortcomings,such as the loss of microvascular details at the end of the vessels.We address the limitations of convolution by introducing the transformer into retinal vessel segmentation.Therefore,we propose a hybrid method for retinal vessel segmentation based on modulated deformable convolution and the transformer,named DT-Net.Firstly,multi-scale image features are extracted by deformable convolution and multi-head selfattention(MHSA).Secondly,image information is recovered,and vessel morphology is refined by the proposed transformer decoder block.Finally,the local prediction results are obtained by the side output layer.The accuracy of the vessel segmentation is improved by the hybrid loss function.Experimental results show that our method obtains good segmentation performance on Specificity(SP),Sensitivity(SE),Accuracy(ACC),Curve(AUC),and F1-score on three publicly available fundus datasets such as DRIVE,STARE,and CHASE_DB1. 展开更多
关键词 Retinal vessel segmentation deformable convolution multi-scale TRANSFORMER hybrid loss function
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Electrical Tree Image Segmentation Using Hybrid Multi Scale Line Tracking Algorithm
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作者 Mohd Annuar Isa Mohamad Nur Khairul Hafizi Rohani +7 位作者 Baharuddin Ismail Mohamad Kamarol Jamil Muzamir Isa Afifah Shuhada Rosmi Mohd Aminudin Jamlos Wan Azani Mustafa Nurulbariah Idris Abdullahi Abubakar Mas’ud 《Computers, Materials & Continua》 SCIE EI 2023年第4期741-760,共20页
Electrical trees are an aging mechanismmost associated with partial discharge(PD)activities in crosslinked polyethylene(XLPE)insulation of high-voltage(HV)cables.Characterization of electrical tree structures gained c... Electrical trees are an aging mechanismmost associated with partial discharge(PD)activities in crosslinked polyethylene(XLPE)insulation of high-voltage(HV)cables.Characterization of electrical tree structures gained considerable attention from researchers since a deep understanding of the tree morphology is required to develop new insulation material.Two-dimensional(2D)optical microscopy is primarily used to examine tree structures and propagation shapes with image segmentation methods.However,since electrical trees can emerge in different shapes such as bush-type or branch-type,treeing images are complicated to segment due to manifestation of convoluted tree branches,leading to a high misclassification rate during segmentation.Therefore,this study proposed a new method for segmenting 2D electrical tree images based on the multi-scale line tracking algorithm(MSLTA)by integrating batch processing method.The proposed method,h-MSLTA aims to provide accurate segmentation of electrical tree images obtained over a period of tree propagation observation under optical microscopy.The initial phase involves XLPE sample preparation and treeing image acquisition under real-time microscopy observation.The treeing images are then sampled and binarized in pre-processing.In the next phase,segmentation of tree structures is performed using the h-MSLTA by utilizing batch processing in multiple instances of treeing duration.Finally,the comparative investigation has been conducted using standard performance assessment metrics,including accuracy,sensitivity,specificity,Dice coefficient and Matthew’s correlation coefficient(MCC).Based on segmentation performance evaluation against several established segmentation methods,h-MSLTA achieved better results of 95.43%accuracy,97.28%specificity,69.43%sensitivity rate with 23.38%and 24.16%average improvement in Dice coefficient and MCC score respectively over the original algorithm.In addition,h-MSLTA produced accurate measurement results of global tree parameters of length and width in comparison with the ground truth image.These results indicated that the proposed method had a solid performance in terms of segmenting electrical tree branches in 2D treeing images compared to other established techniques. 展开更多
关键词 Image segmentation multi-scale line tracking electrical tree partial discharge high-voltage cable
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A Lightweight Road Scene Semantic Segmentation Algorithm
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作者 Jiansheng Peng Qing Yang Yaru Hou 《Computers, Materials & Continua》 SCIE EI 2023年第11期1929-1948,共20页
In recent years,with the continuous deepening of smart city construction,there have been significant changes and improvements in the field of intelligent transportation.The semantic segmentation of road scenes has imp... In recent years,with the continuous deepening of smart city construction,there have been significant changes and improvements in the field of intelligent transportation.The semantic segmentation of road scenes has important practical significance in the fields of automatic driving,transportation planning,and intelligent transportation systems.However,the current mainstream lightweight semantic segmentation models in road scene segmentation face problems such as poor segmentation performance of small targets and insufficient refinement of segmentation edges.Therefore,this article proposes a lightweight semantic segmentation model based on the LiteSeg model improvement to address these issues.The model uses the lightweight backbone network MobileNet instead of the LiteSeg backbone network to reduce the network parameters and computation,and combines the Coordinate Attention(CA)mechanism to help the network capture long-distance dependencies.At the same time,by combining the dependencies of spatial information and channel information,the Spatial and Channel Network(SCNet)attention mechanism is proposed to improve the feature extraction ability of the model.Finally,a multiscale transposed attention encoding(MTAE)module was proposed to obtain features of different resolutions and perform feature fusion.In this paper,the proposed model is verified on the Cityscapes dataset.The experimental results show that the addition of SCNet and MTAE modules increases the mean Intersection over Union(mIoU)of the original LiteSeg model by 4.69%.On this basis,the backbone network is replaced with MobileNet,and the CA model is added at the same time.At the cost of increasing the minimum model parameters and computing costs,the mIoU of the original LiteSeg model is increased by 2.46%.This article also compares the proposed model with some current lightweight semantic segmentation models,and experiments show that the comprehensive performance of the proposed model is the best,especially in achieving excellent results in small object segmentation.Finally,this article will conduct generalization testing on the KITTI dataset for the proposed model,and the experimental results show that the proposed algorithm has a certain degree of generalization. 展开更多
关键词 Semantic segmentation LIGHTWEIGHT road scenes multi-scale transposition attention encoding(MTAE)
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DCAU-Net:dense convolutional attention U-Net for segmentation of intracranial aneurysm images
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作者 Wenwen Yuan Yanjun Peng +2 位作者 Yanfei Guo Yande Ren Qianwen Xue 《Visual Computing for Industry,Biomedicine,and Art》 EI 2022年第1期99-114,共16页
Segmentation of intracranial aneurysm images acquired using magnetic resonance angiography(MRA)is essential for medical auxiliary treatments,which can effectively prevent subarachnoid hemorrhages.This paper proposes a... Segmentation of intracranial aneurysm images acquired using magnetic resonance angiography(MRA)is essential for medical auxiliary treatments,which can effectively prevent subarachnoid hemorrhages.This paper proposes an image segmentation model based on a dense convolutional attention U-Net,which fuses deep and rich semantic information with shallow-detail information for adaptive and accurate segmentation of MRA-acquired aneurysm images with large size differences.The U-Net model serves as a backbone,combining dense block and convolution block attention module(CBAM).The dense block is composed of a batch normalization layer,an randomly rectified linear unit activation function,and a convolutional layer,for mitigation of vanishing gradients,for multiplexing of aneurysm features,and for improving the network training efficiency.The CBAM is composed of a channel attention module and a spatial attention module,improving the segmentation performance of feature discrimination and enhancing the acquisition of key feature information.Owing to the large variation of aneurysm sizes,multi-scale fusion is performed during up-sampling,for adaptive segmentation of MRA-acquired aneurysm images.The model was tested on the MICCAI 2020 ADAM dataset,and its generalizability was validated on the clinical aneurysm dataset(aneurysm sizes:<3 mm,3–7 mm,and>7 mm)supplied by the Affiliated Hospital of Qingdao University.A good clinical application segmentation performance was demonstrated. 展开更多
关键词 Deep learning Intracranial aneurysm segmentation Magnetic resonance angiography multi-scale fusion
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Medical Image Segmentation Based on Wavelet Analysis and Gradient Vector Flow
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作者 Ji Zhao Lina Zhang Minmin Yin 《Journal of Software Engineering and Applications》 2014年第12期1019-1030,共12页
Medical image segmentation is one of the key technologies in computer aided diagnosis. Due to the complexity and diversity of medical images, the wavelet multi-scale analysis is introduced into GVF (gradient vector fl... Medical image segmentation is one of the key technologies in computer aided diagnosis. Due to the complexity and diversity of medical images, the wavelet multi-scale analysis is introduced into GVF (gradient vector flow) snake model. The modulus values of each scale and phase angle values are calculated using wavelet transform, and the local maximum points of modulus values, which are the contours of the object edges, are obtained along phase angle direction at each scale. Then, location of the edges of the object and segmentation is implemented by GVF snake model. The experiments on some medical images show that the improved algorithm has small amount of computation, fast convergence and good robustness to noise. 展开更多
关键词 Pattern Recognition IMAGE segmentation GVF SNAKE Model WAVELET multi-scale Analysis MEDICAL IMAGE
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A Transformer-Assisted Cascade Learning Network for Choroidal Vessel Segmentation
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作者 温阳 吴依林 +6 位作者 毕磊 石武祯 刘潇骁 许毓鹏 许迅 曹文明 冯大淦 《Journal of Computer Science & Technology》 SCIE EI CSCD 2024年第2期286-304,共19页
As a highly vascular eye part,the choroid is crucial in various eye disease diagnoses.However,limited research has focused on the inner structure of the choroid due to the challenges in obtaining sufficient accurate l... As a highly vascular eye part,the choroid is crucial in various eye disease diagnoses.However,limited research has focused on the inner structure of the choroid due to the challenges in obtaining sufficient accurate label data,particularly for the choroidal vessels.Meanwhile,the existing direct choroidal vessel segmentation methods for the intelligent diagnosis of vascular assisted ophthalmic diseases are still unsatisfactory due to noise data,while the synergistic segmentation methods compromise vessel segmentation performance for the choroid layer segmentation tasks.Common cascaded structures grapple with error propagation during training.To address these challenges,we propose a cascade learning segmentation method for the inner vessel structures of the choroid in this paper.Specifically,we propose TransformerAssisted Cascade Learning Network(TACLNet)for choroidal vessel segmentation,which comprises a two-stage training strategy:pre-training for choroid layer segmentation and joint training for choroid layer and choroidal vessel segmentation.We also enhance the skip connection structures by introducing a multi-scale subtraction connection module designated as MSC,capturing differential and detailed information simultaneously.Additionally,we implement an auxiliary Transformer branch named ATB to integrate global features into the segmentation process.Experimental results exhibit that our method achieves the state-of-the-art performance for choroidal vessel segmentation.Besides,we further validate the significant superiority of the proposed method for retinal fluid segmentation in optical coherence tomography(OCT)scans on a publicly available dataset.All these fully prove that our TACLNet contributes to the advancement of choroidal vessel segmentation and is of great significance for ophthalmic research and clinical application. 展开更多
关键词 choroidal vessel segmentation optical coherence tomography(OCT) Transformer-assisted cascade learning retinal fluid segmentation multi-scale feature extraction
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Crustal density structure of the southern segment of the Liaocheng-Lankao fault, China 被引量:1
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作者 Lei Jiang Lanbo Liu +4 位作者 Zhiping Xu Xiaoguo Deng Lipu Yang Wei Xiong Shunqiang Xu 《Geodesy and Geodynamics》 2019年第5期347-355,共9页
The 1:200,000 middle-large scale Bouguer gravity anomaly data covering the southern segment of the Liaocheng-Lankao fault(SLLF)and its vicinity are analyzed with two methods.First,the Bouguer gravity anomaly data are ... The 1:200,000 middle-large scale Bouguer gravity anomaly data covering the southern segment of the Liaocheng-Lankao fault(SLLF)and its vicinity are analyzed with two methods.First,the Bouguer gravity anomaly data are decomposed by two-dimensional(2 D)wavelet to make the family of multi-scale modes correspond with density structure at different depths.Second,a two and half dimension(2.5 D)human-computer interaction inversion of the Bouguer gravity anomaly data are conducted with the constraints provided by two deep seismic sounding profiles(DSS1 and DSS2)crossing the study area to get the crustal density profiles.Based on the integrated study,we can draw the following conclusions:1)SLLF appears to be a deep fault with almost vertical dipping and rooted into the uppermost mantle;2)In the middle to upper crust SLLF shows an clear turning patterns and segmentation features;3)In the study area the epicentral distributions of the precisely re-located small earthquakes and the historical large earthquakes have a good correspondence with the turning patterns and segmentation features of SLLF;and 4)The results of the horizontal slices from 2 D wavelet decomposition show that there are significant differences in the density structure on the two sides of the fault.A well-defined concave structure with low density exists in the upper crust of the Dongming Depression on the west side of the fault,with the concave center being estimated at a depth of about 8 km.In contrast,the upper crust on the east side presents a relative thinner pattern in depth with a bit higher density.Meanwhile,the low-density structure in the middle crust underneath the fault is presumably caused by the uplift of the upper mantle materials and their intrusion along the deep rupture system.This paper clarified the inconsistency of fault system and epicenters of small earthquakes from upper to lower crust.The results indicated that the fault system plays an important governing role to the seismicity in this area. 展开更多
关键词 SOUTHERN segment of the Liaocheng-Lankao fault(SLLF) Bouguer gravity ANOMALIES Density structure Dongming depression multi-scale wavelet decomposition Epicenters of small EARTHQUAKES
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Landslide susceptibility prediction using slope unit-based machine learning models considering the heterogeneity of conditioning factors 被引量:8
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作者 Zhilu Chang Filippo Catani +4 位作者 Faming Huang Gengzhe Liu Sansar Raj Meena Jinsong Huang Chuangbing Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第5期1127-1143,共17页
To perform landslide susceptibility prediction(LSP),it is important to select appropriate mapping unit and landslide-related conditioning factors.The efficient and automatic multi-scale segmentation(MSS)method propose... To perform landslide susceptibility prediction(LSP),it is important to select appropriate mapping unit and landslide-related conditioning factors.The efficient and automatic multi-scale segmentation(MSS)method proposed by the authors promotes the application of slope units.However,LSP modeling based on these slope units has not been performed.Moreover,the heterogeneity of conditioning factors in slope units is neglected,leading to incomplete input variables of LSP modeling.In this study,the slope units extracted by the MSS method are used to construct LSP modeling,and the heterogeneity of conditioning factors is represented by the internal variations of conditioning factors within slope unit using the descriptive statistics features of mean,standard deviation and range.Thus,slope units-based machine learning models considering internal variations of conditioning factors(variant slope-machine learning)are proposed.The Chongyi County is selected as the case study and is divided into 53,055 slope units.Fifteen original slope unit-based conditioning factors are expanded to 38 slope unit-based conditioning factors through considering their internal variations.Random forest(RF)and multi-layer perceptron(MLP)machine learning models are used to construct variant Slope-RF and Slope-MLP models.Meanwhile,the Slope-RF and Slope-MLP models without considering the internal variations of conditioning factors,and conventional grid units-based machine learning(Grid-RF and MLP)models are built for comparisons through the LSP performance assessments.Results show that the variant Slopemachine learning models have higher LSP performances than Slope-machine learning models;LSP results of variant Slope-machine learning models have stronger directivity and practical application than Grid-machine learning models.It is concluded that slope units extracted by MSS method can be appropriate for LSP modeling,and the heterogeneity of conditioning factors within slope units can more comprehensively reflect the relationships between conditioning factors and landslides.The research results have important reference significance for land use and landslide prevention. 展开更多
关键词 Landslide susceptibility prediction(LSP) Slope unit multi-scale segmentation method(MSS) Heterogeneity of conditioning factors Machine learning models
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家族性局灶节段性肾小球硬化的基因研究 被引量:1
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作者 李国民 卢思广 +3 位作者 顾兆坤 王凤英 吕进泉 吴丽华 《江苏大学学报(医学版)》 CAS 2007年第5期411-414,418,共5页
目的:探讨家族性局灶节段性肾小球硬化(familial focal segmental glomerulosclerosis,FFSGS)基因与染色体1q25-31区域的连锁关系。方法:1个中国皖北地区3代FFSGS家系,采集本家系中27名成员的外周血样,选择位于1q25-31上的10微卫星标志:... 目的:探讨家族性局灶节段性肾小球硬化(familial focal segmental glomerulosclerosis,FFSGS)基因与染色体1q25-31区域的连锁关系。方法:1个中国皖北地区3代FFSGS家系,采集本家系中27名成员的外周血样,选择位于1q25-31上的10微卫星标志:D19S49、D1S452、D1S242、D1S416、D1S240、D1S254、D1S202、D1S222、D1S238和D1S413,应用聚合酶链式反应(PCR)得到扩增产物片断,采用ABI PRISMTM310 Genetic Analyze测定PCR产物片断大小。利用Genescan软件(3.1版)、Genetyper(3.7版)处理后得到检测片断大小,根据相应微卫星标记的产物片断大小不同,得到每个样本的基因型。对基因型数据进行校对后,用连锁分析软件LINKAGE的MLINK程序计算每个标记的两点间LOD(log odds)值。根据两点LOD值判断连锁关系。结果:连锁分析结果显示所有微卫星标记两点间LOD值在不同重组率时均小于0,所有LOD值在重组率为0.0时均小于-2,说明该FFSGS家系疾病基因与1q25-31区域没有连锁关系。结论:该家族疾病基因与已报道的FFSGS定位区域(1q25-31区域)没有连锁关系。 展开更多
关键词 家族性局灶节段性肾小球硬化 常染色体隐性遗传 连锁分析 异质性
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基于多尺度继承性SAR图像分割算法 被引量:1
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作者 刘忠 刘爱平 《计算机应用研究》 CSCD 北大核心 2010年第7期2735-2737,2750,共4页
针对高分辨率SAR图像的分割问题,提出一种基于多尺度继承性的分割算法。该算法综合利用图像的宏观和微观特征,将传统的单尺度信息处理技术纳入尺度不断变化的动态分析框架中,更容易获得图像的本质特征。同时,使用异性扩散方程获得多尺... 针对高分辨率SAR图像的分割问题,提出一种基于多尺度继承性的分割算法。该算法综合利用图像的宏观和微观特征,将传统的单尺度信息处理技术纳入尺度不断变化的动态分析框架中,更容易获得图像的本质特征。同时,使用异性扩散方程获得多尺度图像序列,采用一种由粗尺度到细尺度的分割策略,先进行粗尺度分割,然后以此分割结果来引导较细尺度层的分割。分割过程中采用迭代自组织的数据分析算法自适应地确定每一层分割的区域个数,较好地建立尺度之间的分割继承关系。该分割算法可以满足不同图像处理任务的需求,也更加符合人的认知过程和视觉处理系统。 展开更多
关键词 多尺度 SAR图像 继承分割 各向异向扩散方程 迭代自组织数据分析
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殊途同归:两代农民工城市融入的比较——基于生命历程的视角 被引量:31
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作者 孙文中 《中国农业大学学报(社会科学版)》 CSSCI 北大核心 2015年第3期68-75,共8页
以30名农民工的务工经商生活史的深度访谈资料为基础,从生命历程视角关照了新老两代农民工自外出务工、城城(乡)流动到选择归宿的生命轨迹。在社会结构及机会结构下,农民工社会融入是依循年龄层级在一系列生命事件中依社会角色变化而进... 以30名农民工的务工经商生活史的深度访谈资料为基础,从生命历程视角关照了新老两代农民工自外出务工、城城(乡)流动到选择归宿的生命轨迹。在社会结构及机会结构下,农民工社会融入是依循年龄层级在一系列生命事件中依社会角色变化而进行反思性自我定位的行动过程。研究表明,两代农民工具有相似的生命轨迹,家庭角色的转变形塑了他们最终的生活期望和社会归属。由于新老两代农民工禀赋差异和代际特征,新生代农民工虽具有更多城市性和现代性,其融入意愿也发生了代际转变,但因面对的机会结构限制和自身能力不足,其社会融入仍具有代际传承性,实质是区隔性融入。 展开更多
关键词 生命历程 农民工 社会融入 代际转变 代际传承 区隔融入
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显微图像的光学薄膜缺陷密度统计 被引量:1
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作者 何长涛 马孜 +2 位作者 王旭阳 陈建国 赵汝进 《光学仪器》 2006年第4期118-123,共6页
薄膜表面缺陷密度统计是改进薄膜表面质量的重要依据。阐述了基于遗传算法的二维最大熵分割算法的原理及实现步骤。采用这种算法对薄膜缺陷图像进行分割,对分割后的图像进行了薄膜缺陷密度的测量。实验结果表明,这种方法对薄膜表面缺陷... 薄膜表面缺陷密度统计是改进薄膜表面质量的重要依据。阐述了基于遗传算法的二维最大熵分割算法的原理及实现步骤。采用这种算法对薄膜缺陷图像进行分割,对分割后的图像进行了薄膜缺陷密度的测量。实验结果表明,这种方法对薄膜表面缺陷提取简单且易于测量,为分析缺陷原因提高薄膜质量起到重要的指导作用。 展开更多
关键词 光学薄膜 图像分割 遗传算法 二维最大熵 缺陷密度
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一种基于MRF的多层遗传递减视频对象分割算法
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作者 张素文 杨富森 丁立新 《武汉理工大学学报(交通科学与工程版)》 2008年第3期458-461,共4页
提出一种视频对象分割方法,将时域信息、空域信息和图像颜色特征有效地结合起来,采用MRF遗传递减式分类来提取视频对象.利用视频帧的颜色特征,在初始分割中采用时空域分水岭方法,建立一个时空域毗连图(ST-RAG);基于时空域毗连图建立马... 提出一种视频对象分割方法,将时域信息、空域信息和图像颜色特征有效地结合起来,采用MRF遗传递减式分类来提取视频对象.利用视频帧的颜色特征,在初始分割中采用时空域分水岭方法,建立一个时空域毗连图(ST-RAG);基于时空域毗连图建立马尔可夫随机场(MRF)模型,在分割过程中采用遗传递减式方法对区域进行合理分类,利用形态学进行后处理,分割出感兴趣的视频对象.实验结果表明所获取的分割方法具有灵活性,且精度高. 展开更多
关键词 视频对象分割 分水岭 MRF模型 遗传递减 对象提取
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