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A deep learning fusion model for accurate classification of brain tumours in Magnetic Resonance images
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作者 Nechirvan Asaad Zebari Chira Nadheef Mohammed +8 位作者 Dilovan Asaad Zebari Mazin Abed Mohammed Diyar Qader Zeebaree Haydar Abdulameer Marhoon Karrar Hameed Abdulkareem Seifedine Kadry Wattana Viriyasitavat Jan Nedoma Radek Martinek 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期790-804,共15页
Detecting brain tumours is complex due to the natural variation in their location, shape, and intensity in images. While having accurate detection and segmentation of brain tumours would be beneficial, current methods... Detecting brain tumours is complex due to the natural variation in their location, shape, and intensity in images. While having accurate detection and segmentation of brain tumours would be beneficial, current methods still need to solve this problem despite the numerous available approaches. Precise analysis of Magnetic Resonance Imaging (MRI) is crucial for detecting, segmenting, and classifying brain tumours in medical diagnostics. Magnetic Resonance Imaging is a vital component in medical diagnosis, and it requires precise, efficient, careful, efficient, and reliable image analysis techniques. The authors developed a Deep Learning (DL) fusion model to classify brain tumours reliably. Deep Learning models require large amounts of training data to achieve good results, so the researchers utilised data augmentation techniques to increase the dataset size for training models. VGG16, ResNet50, and convolutional deep belief networks networks extracted deep features from MRI images. Softmax was used as the classifier, and the training set was supplemented with intentionally created MRI images of brain tumours in addition to the genuine ones. The features of two DL models were combined in the proposed model to generate a fusion model, which significantly increased classification accuracy. An openly accessible dataset from the internet was used to test the model's performance, and the experimental results showed that the proposed fusion model achieved a classification accuracy of 98.98%. Finally, the results were compared with existing methods, and the proposed model outperformed them significantly. 展开更多
关键词 brain tumour deep learning feature fusion model MRI images multi‐classification
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DETERMINATION OF UNKNOWN CAMERA PARAMETERS FOR THE PERSPECTIVE IMAGES
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作者 昂海松 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期95+91-94,共5页
To obtain an accurate 3 D object configuration from images,the essential perspective characteristics must be considered. Several new inverse transformation relations of the perspective image lines are given. Utiliz... To obtain an accurate 3 D object configuration from images,the essential perspective characteristics must be considered. Several new inverse transformation relations of the perspective image lines are given. Utilizing the analytic transformation relations, an optimization procedure for obtaining the unknown camera parameters of images is presented in this paper. A 3 D reproduction method and examples are introduced. 展开更多
关键词 perspective projection optimization perspective image 3 D reproduction
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Contribution of Imagery in the Diagnosis of Multisystemic Sarcoidosis in the Service Radiology Department of the Mother and Child Hospital “Le Luxembourg” in Bamako: A Case Report
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作者 Mariko Mahamane Camara Mamoudou +7 位作者 Keita Aboubacar Sidiki N’Diaye Mahamadou Camara Mody Abdoulaye Fofana Youssouf Traoré Mohamed Maba Sidibé Siaka Sanogo Souleymane Keita Adama Diaman 《Open Journal of Medical Imaging》 2024年第3期79-85,共7页
The aim of this study was to report a case of multi-visceral sarcoidosis at the Mother-Child Hospital Center (CHME) “Le Luxembourg” in Bamako, Mali. Observation: This is a patient aged 62 at the time of consultation... The aim of this study was to report a case of multi-visceral sarcoidosis at the Mother-Child Hospital Center (CHME) “Le Luxembourg” in Bamako, Mali. Observation: This is a patient aged 62 at the time of consultation, a housewife, residing in the Banconi district, who was referred to us for thoracic-abdominopelvic imaging for chronic liver disease. After several diagnostic errors, the thoracic-abdominopelvic CT scan and liver MRI performed in our center showed, at the thoracoabdominal level, bilateral diffuse pulmonary micronodules and bilateral mediastinal-hilar lymphadenopathy;on the abdominal level, a dysmorphic liver with plaques of steatosis and a granular appearance of the liver parenchyma without periportal fibrosis. These imaging data combined with those from the liver nodule biopsy and biology confirmed the diagnosis of sarcoidosis type II. Treatment with corticosteroids gave satisfactory results and the patient recovered after 18 months. Clinical and CT monitoring 2 years from the start of the disease and 2 months from the end of treatment showed complete resolution of the lesions. Conclusion: The multi-visceral location of sarcoidosis is an entity whose diagnosis remains difficult;diagnostic and interventional imaging has an important place in its management. 展开更多
关键词 SARCOIDOSIS multi VISCERAL imaging CHME Luxembourg
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A Lightweight Convolutional Neural Network with Hierarchical Multi-Scale Feature Fusion for Image Classification
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作者 Adama Dembele Ronald Waweru Mwangi Ananda Omutokoh Kube 《Journal of Computer and Communications》 2024年第2期173-200,共28页
Convolutional neural networks (CNNs) are widely used in image classification tasks, but their increasing model size and computation make them challenging to implement on embedded systems with constrained hardware reso... Convolutional neural networks (CNNs) are widely used in image classification tasks, but their increasing model size and computation make them challenging to implement on embedded systems with constrained hardware resources. To address this issue, the MobileNetV1 network was developed, which employs depthwise convolution to reduce network complexity. MobileNetV1 employs a stride of 2 in several convolutional layers to decrease the spatial resolution of feature maps, thereby lowering computational costs. However, this stride setting can lead to a loss of spatial information, particularly affecting the detection and representation of smaller objects or finer details in images. To maintain the trade-off between complexity and model performance, a lightweight convolutional neural network with hierarchical multi-scale feature fusion based on the MobileNetV1 network is proposed. The network consists of two main subnetworks. The first subnetwork uses a depthwise dilated separable convolution (DDSC) layer to learn imaging features with fewer parameters, which results in a lightweight and computationally inexpensive network. Furthermore, depthwise dilated convolution in DDSC layer effectively expands the field of view of filters, allowing them to incorporate a larger context. The second subnetwork is a hierarchical multi-scale feature fusion (HMFF) module that uses parallel multi-resolution branches architecture to process the input feature map in order to extract the multi-scale feature information of the input image. Experimental results on the CIFAR-10, Malaria, and KvasirV1 datasets demonstrate that the proposed method is efficient, reducing the network parameters and computational cost by 65.02% and 39.78%, respectively, while maintaining the network performance compared to the MobileNetV1 baseline. 展开更多
关键词 MobileNet image Classification Lightweight Convolutional Neural Network Depthwise Dilated Separable Convolution Hierarchical multi-Scale Feature Fusion
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Free form deformation and symmetry constraint‐based multimodal brain image registration using generative adversarial nets
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作者 Xingxing Zhu Mingyue Ding Xuming Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1492-1506,共15页
Multi‐modal brain image registration has been widely applied to functional localisation,neurosurgery and computational anatomy.The existing registration methods based on the dense deformation fields involve too many ... Multi‐modal brain image registration has been widely applied to functional localisation,neurosurgery and computational anatomy.The existing registration methods based on the dense deformation fields involve too many parameters,which is not conducive to the exploration of correct spatial correspondence between the float and reference images.Meanwhile,the unidirectional registration may involve the deformation folding,which will result in the change of topology during registration.To address these issues,this work has presented an unsupervised image registration method using the free form deformation(FFD)and the symmetry constraint‐based generative adversarial networks(FSGAN).The FSGAN utilises the principle component analysis network‐based structural representations of the reference and float images as the inputs and uses the generator to learn the FFD model parameters,thereby producing two deformation fields.Meanwhile,the FSGAN uses two discriminators to decide whether the bilateral registration have been realised simultaneously.Besides,the symmetry constraint is utilised to construct the loss function,thereby avoiding the deformation folding.Experiments on BrainWeb,high grade gliomas,IXI and LPBA40 show that compared with state‐of‐the‐art methods,the FSGAN provides superior performance in terms of visual comparisons and such quantitative indexes as dice value,target registration error and computational efficiency. 展开更多
关键词 Free‐form deformation Generative adversarial nets multi‐modal brain image registration Structural representation Symmetry constraint
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Covid-19 Diagnosis Using a Deep Learning Ensemble Model with Chest X-Ray Images
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作者 Fuat Türk 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1357-1373,共17页
Covid-19 is a deadly virus that is rapidly spread around the world towards the end of the 2020.The consequences of this virus are quite frightening,especially when accompanied by an underlying disease.The novelty of t... Covid-19 is a deadly virus that is rapidly spread around the world towards the end of the 2020.The consequences of this virus are quite frightening,especially when accompanied by an underlying disease.The novelty of the virus,the constant emergence of different variants and its rapid spread have a negative impact on the control and treatment process.Although the new test kits provide almost certain results,chest X-rays are extremely important to detect the progression and degree of the disease.In addition to the Covid-19 virus,pneumonia and harmless opacity of the lungs also complicate the diagnosis.Considering the negative results caused by the virus and the treatment costs,the importance of fast and accurate diagnosis is clearly seen.In this context,deep learning methods appear as an extremely popular approach.In this study,a hybrid model design with superior properties of convolutional neural networks is presented to correctly classify the Covid-19 disease.In addition,in order to contribute to the literature,a suitable dataset with balanced case numbers that can be used in all artificial intelligence classification studies is presented.With this ensemble model design,quite remarkable results are obtained for the diagnosis of three and four-class Covid-19.The proposed model can classify normal,pneumonia,and Covid-19 with 92.6%accuracy and 82.6%for normal,pneumonia,Covid-19,and lung opacity. 展开更多
关键词 Deep learning multi class diagnosis Covid-19 Covid-19 ensemble model medical image analysis
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Electromagnetic scattering and imaging simulation of extremely large-scale sea-ship scene based on GPU parallel technology
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作者 Cheng-Wei Zhang Zhi-Qin Zhao +2 位作者 Wei Yang Li-Lai Zhou Hai-Yu Zhu 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第2期16-23,共8页
Aiming to solve the bottleneck problem of electromagnetic scattering simulation in the scenes of extremely large-scale seas and ships,a high-frequency method by using graphics processing unit(GPU)parallel acceleration... Aiming to solve the bottleneck problem of electromagnetic scattering simulation in the scenes of extremely large-scale seas and ships,a high-frequency method by using graphics processing unit(GPU)parallel acceleration technique is proposed.For the implementation of different electromagnetic methods of physical optics(PO),shooting and bouncing ray(SBR),and physical theory of diffraction(PTD),a parallel computing scheme based on the CPU-GPU parallel computing scheme is realized to balance computing tasks.Finally,a multi-GPU framework is further proposed to solve the computational difficulty caused by the massive number of ray tubes in the ray tracing process.By using the established simulation platform,signals of ships at different seas are simulated and their images are achieved as well.It is shown that the higher sea states degrade the averaged peak signal-to-noise ratio(PSNR)of radar image. 展开更多
关键词 multi graphics processing unit Radar imaging Sea-ship Shooting and bouncing rays
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Locality preserving fusion of multi-source images for sea-ice classification 被引量:1
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作者 Zhiqiang Yu Tingwei Wang +2 位作者 Xi Zhang Jie Zhang Peng Ren 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第7期129-136,共8页
We present a novel sea-ice classification framework based on locality preserving fusion of multi-source images information.The locality preserving fusion arises from two-fold,i.e.,the local characterization in both sp... We present a novel sea-ice classification framework based on locality preserving fusion of multi-source images information.The locality preserving fusion arises from two-fold,i.e.,the local characterization in both spatial and feature domains.We commence by simultaneously learning a projection matrix,which preserves spatial localities,and a similarity matrix,which encodes feature similarities.We map the pixels of multi-source images by the projection matrix to a set fusion vectors that preserve spatial localities of the image.On the other hand,by applying the Laplacian eigen-decomposition to the similarity matrix,we obtain another set of fusion vectors that preserve the feature local similarities.We concatenate the fusion vectors for both spatial and feature locality preservation and obtain the fusion image.Finally,we classify the fusion image pixels by a novel sliding ensemble strategy,which enhances the locality preservation in classification.Our locality preserving fusion framework is effective in classifying multi-source sea-ice images(e.g.,multi-spectral and synthetic aperture radar(SAR)images)because it not only comprehensively captures the spatial neighboring relationships but also intrinsically characterizes the feature associations between different types of sea-ices.Experimental evaluations validate the effectiveness of our framework. 展开更多
关键词 SEA-ICE CLASSIFICATION multi-SOURCE image FUSION ensemble CLASSIFICATION
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Accuracy Analysis on the Automatic Registration of Multi-Source Remote Sensing Images Based on the Software of ERDAS Imagine 被引量:1
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作者 Debao Yuan Ximin Cui +2 位作者 Yahui Qiu Xueyun Gu Li Zhang 《Advances in Remote Sensing》 2013年第2期140-148,共9页
The automatic registration of multi-source remote sensing images (RSI) is a research hotspot of remote sensing image preprocessing currently. A special automatic image registration module named the Image Autosync has ... The automatic registration of multi-source remote sensing images (RSI) is a research hotspot of remote sensing image preprocessing currently. A special automatic image registration module named the Image Autosync has been embedded into the ERDAS IMAGINE software of version 9.0 and above. The registration accuracies of the module verified for the remote sensing images obtained from different platforms or their different spatial resolution. Four tested registration experiments are discussed in this article to analyze the accuracy differences based on the remote sensing data which have different spatial resolution. The impact factors inducing the differences of registration accuracy are also analyzed. 展开更多
关键词 multi-SOURCE REMOTE SENSING images Automatic REGISTRATION image Autosync REGISTRATION ACCURACY
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Multi⁃Scale Dilated Convolutional Neural Network for Hyperspectral Image Classification
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作者 Shanshan Zheng Wen Liu +3 位作者 Rui Shan Jingyi Zhao Guoqian Jiang Zhi Zhang 《Journal of Harbin Institute of Technology(New Series)》 CAS 2021年第4期25-32,共8页
Aiming at the problem of image information loss,dilated convolution is introduced and a novel multi⁃scale dilated convolutional neural network(MDCNN)is proposed.Dilated convolution can polymerize image multi⁃scale inf... Aiming at the problem of image information loss,dilated convolution is introduced and a novel multi⁃scale dilated convolutional neural network(MDCNN)is proposed.Dilated convolution can polymerize image multi⁃scale information without reducing the resolution.The first layer of the network used spectral convolutional step to reduce dimensionality.Then the multi⁃scale aggregation extracted multi⁃scale features through applying dilated convolution and shortcut connection.The extracted features which represent properties of data were fed through Softmax to predict the samples.MDCNN achieved the overall accuracy of 99.58% and 99.92% on two public datasets,Indian Pines and Pavia University.Compared with four other existing models,the results illustrate that MDCNN can extract better discriminative features and achieve higher classification performance. 展开更多
关键词 multi⁃scale aggregation dilated convolution hyperspectral image classification(HSIC) shortcut connection
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The Reality of Nigerian Image From the Perspective of The Home Videos
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作者 Sunday Olayinka Alawode Uduakobong Sunday 《Journalism and Mass Communication》 2014年第3期180-196,共17页
The home video through its offering plays pivotal roles of information, education and entertainment. It has provided knowledge to the viewing audience and directs their attention to issues to think about and/or learn.... The home video through its offering plays pivotal roles of information, education and entertainment. It has provided knowledge to the viewing audience and directs their attention to issues to think about and/or learn. Popularly called Nollywood, the home video industry has brought scholars, reporters, reviewer, journalists, investors, and different kinds of people to the country; to investigate, invest, and observe the industry or network with people. Through the portrayals and representations of Nigeria and its people, a lot of people, especially foreigners and Nigerians in the Diaspora have come to understand the socio-economic and political terrain of the nation based on the home videos offerings; thus the need to x-ray the depictions in the Nigerian home video films to ascertain the reality of their Nigerian image from the perspectives. The study was undertaken through content analysis of 50 video films which were televised as programmes on television stations in Lagos and Africa Magic (a cable network station), within the framework of agenda-setting and cultivation theories. The results reveal that while the home video producers have effectively revealed Nigerians as religious and traditional people, very little has been done to portray the economic and investment potentials of the nation; the nation's symbols like flags, coat of arm, currencies amongst others are barely revealed; negative attitudes of get-rich-quick, get-rich-at-all-cost, witchcraft, and fetish practices as well as violence, hooliganism, and ritualism amongst other things are often exaggerated in the films. Following the home video portrayals and representations, it could be imagined that the Nigerian urban environment is as beautiful and rich with predominantly affluent and flamboyant people as are depicted in the home videos. The misrepresentations, overrepresentations, and under-presentations of the nation's image in the home video can be very detrimental to the nation's socio-economic development especially as the nation's destiny is indirectly related to its image. They can further pose challenges to the attitudes and responses of people from other nations to the Nigerian citizens within and outside the country. Furthermore, some Nigerian citizens, especially the youths could aspire to and learn certain lifestyles and attitudes projected in the home videos as acceptable. 展开更多
关键词 REALITY imagE home video perspective
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Characterization of land cover types in Xilin River Basin using multi-temporal Landsat images 被引量:2
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作者 CHENSiqing LIUJiyuan +1 位作者 ZHUANGDafang XIAOXiangming 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期131-138,共8页
This study conducted computer-aided image analysis of land use and land cover in Xilin River Basin, Inner Mongolia, using 4 sets of Landsat TM/ETM+ images acquired on July 31, 1987, August 11, 1991, Sep... This study conducted computer-aided image analysis of land use and land cover in Xilin River Basin, Inner Mongolia, using 4 sets of Landsat TM/ETM+ images acquired on July 31, 1987, August 11, 1991, September 27, 1997 and May 23, 2000, respectively. Primarily, 17 sub-class land cover types were recognized, including nine grassland types at community level: F.sibiricum steppe, S.baicalensis steppe, A.chinensis+ forbs steppe, A.chinensis+ bunchgrass steppe, A.chinensis+ Ar.frigida steppe, S.grandis+ A.chinensis steppe, S.grandis+ bunchgrass steppe, S.krylavii steppe, Ar.frigida steppe and eight non-grassland types: active cropland, harvested cropland, urban area, wetland, desertified land, saline and alkaline land, cloud, water body + cloud shadow. To eliminate the classification error existing among different sub-types of the same gross type, the 17 sub-class land cover types were grouped into five gross types: meadow grassland, temperate grassland, desert grassland, cropland and non-grassland. The overall classification accuracy of the five land cover types was 81.0% for 1987, 81.7% for 1991, 80.1% for 1997 and 78.2% for 2000. 展开更多
关键词 land-use/land cover classification multi-temporal Landsat images Xilin River Basin CLC number:F301.24 TP79
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Chinese Image in American and British Literature from the Perspective of"Otherness"
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作者 Jun ZHANG 《International Journal of Technology Management》 2015年第7期25-27,共3页
In the US and British literature, there are many works using China or the Chinese people as depict objects. With the development of American and British literature, the shape of the image of China is diverse. Currentl... In the US and British literature, there are many works using China or the Chinese people as depict objects. With the development of American and British literature, the shape of the image of China is diverse. Currently, the research of the image of China or Chinese people in the US and British literature has yielded fruitful results, the majority concentrated on the study before the new century writers and representative works. In the new century, the causes and significance of the image of China and the Chinese people in American literature have the positive impact on self-awareness and self-construction of the China' s image. 展开更多
关键词 perspective of othemess the US and British literature Chinese image
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Study of Forest Cover Change Dynamics between 2000 and 2015 in the Ikongo District of Madagascar Using Multi-Temporal Landsat Satellite Images 被引量:1
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作者 Aimé Richard Hajalalaina Arisetra Razafinimaro Nicolas Ratolotriniaina 《Advances in Remote Sensing》 2021年第3期78-91,共14页
Satellite images are considered reliable data that preserve land cover information. In the field of remote sensing, these images allow relevant analyses of changes in space over time through the use of computer tools.... Satellite images are considered reliable data that preserve land cover information. In the field of remote sensing, these images allow relevant analyses of changes in space over time through the use of computer tools. In this study, we have applied the “discriminant” change detection algorithm. In this, we have verified its effectiveness in multi-temporal studies. Also, we have determined the change in forest dynamics in the Ikongo district of Madagascar between 2000 and 2015. During the treatments, we have used the Landsat TM satellite images for the years 2000, 2005 and 2010 as well as ETM+ for 2015. Thus, analyses carried out have allowed us to note that between 2000-2005, 1.4% of natural forest disappeared. And, between 2005-2010, forests degradation<span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">was 1.8%. Also, between 2010-2015, about 0.5% of the natural forest conserved in 2010 disappeared. Furthermore, we have found that the discriminant algorithm is considerably efficient in terms of monitoring the dynamics of forest cover change.</span></span></span> 展开更多
关键词 Remote Sensing image Processing Change Detect multi-TEMPORAL LANDSAT Forest Covert
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Auto-expanded multi query examples technology in content-based image retrieval 被引量:1
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作者 王小玲 谢康林 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期287-292,共6页
In order to narrow the semantic gap existing in content-based image retrieval (CBIR),a novel retrieval technology called auto-extended multi query examples (AMQE) is proposed.It expands the single one query image ... In order to narrow the semantic gap existing in content-based image retrieval (CBIR),a novel retrieval technology called auto-extended multi query examples (AMQE) is proposed.It expands the single one query image used in traditional image retrieval into multi query examples so as to include more image features related with semantics.Retrieving images for each of the multi query examples and integrating the retrieval results,more relevant images can be obtained.The property of the recall-precision curve of a general retrieval algorithm and the K-means clustering method are used to realize the expansion according to the distance of image features of the initially retrieved images.The experimental results demonstrate that the AMQE technology can greatly improve the recall and precision of the original algorithms. 展开更多
关键词 content-based image retrieval SEMANTIC multi query examples K-means clustering
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Determination of rice panicle numbers during heading by multi-angle imaging 被引量:20
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作者 Lingfeng Duan Chenglong Huang +3 位作者 Guoxing Chen Lizhong Xiong Qian Liu Wanneng Yang 《The Crop Journal》 SCIE CAS CSCD 2015年第3期211-219,共9页
Plant phenomics has the potential to accelerate progress in understanding gene functions and environmental responses. Progress has been made in automating high-throughput plant phenotyping. However, few studies have i... Plant phenomics has the potential to accelerate progress in understanding gene functions and environmental responses. Progress has been made in automating high-throughput plant phenotyping. However, few studies have investigated automated rice panicle counting. This paper describes a novel method for automatically and nonintrusively determining rice panicle numbers during the full heading stage by analyzing color images of rice plants taken from multiple angles. Pot-grown rice plants were transferred via an industrial conveyer to an imaging chamber. Color images from different angles were automatically acquired as a turntable rotated the plant. The images were then analyzed and the panicle number of each plant was determined. The image analysis pipeline consisted of extracting the i2 plane from the original color image, segmenting the image, discriminating the panicles from the rest of the plant using an artificial neural network, and calculating the panicle number in the current image. The panicle number of the plant was taken as the maximum of the panicle numbers extracted from all 12 multi-angle images. A total of 105 rice plants during the full heading stage were examined to test the performance of the method. The mean absolute error of the manual and automatic count was 0.5, with 95.3% of the plants yielding absolute errors within ± 1. The method will be useful for evaluating rice panicles and will serve as an important supplementary method for high-throughput rice phenotyping. 展开更多
关键词 Plant PHENOTYPING RICE PANICLE NUMBER multi-angle imagING image analysis
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Performance Validation and Analysis for Multi-Method Fusion Based Image Quality Metrics in A New Image Database 被引量:3
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作者 Xiaoyu Ma Xiuhua Jiang Da Pan 《China Communications》 SCIE CSCD 2019年第8期147-161,共15页
Considering that there is no single full reference image quality assessment method that could give the best performance in all situations, some multi-method fusion metrics were proposed. Machine learning techniques ar... Considering that there is no single full reference image quality assessment method that could give the best performance in all situations, some multi-method fusion metrics were proposed. Machine learning techniques are often involved in such multi-method fusion metrics so that its output would be more consistent with human visual perceptions. On the other hand, the robustness and generalization ability of these multi-method fusion metrics are questioned because of the scarce of images with mean opinion scores. In order to comprehensively validate whether or not the generalization ability of such multi-method fusion IQA metrics are satisfying, we construct a new image database which contains up to 60 reference images. The newly built image database is then used to test the generalization ability of different multi-method fusion IQA metrics. Cross database validation experiment indicates that in our new image database, the performances of all the multi-method fusion IQA metrics have no statistical significant different with some single-method IQA metrics such as FSIM and MAD. In the end, a thorough analysis is given to explain why the performance of multi-method fusion IQA framework drop significantly in cross database validation. 展开更多
关键词 full REFERENCE imagE quality assessment imagE DATABASE multi-method FUSION
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Multi-resolution image segmentation based on Gaussian mixture model 被引量:5
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作者 Tang Yinggan Liu Dong Guan Xinping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期870-874,共5页
Mixture model based image segmentation method, which assumes that image pixels are independent and do not consider the position relationship between pixels, is not robust to noise and usually leads to misclassificatio... Mixture model based image segmentation method, which assumes that image pixels are independent and do not consider the position relationship between pixels, is not robust to noise and usually leads to misclassification. A new segmentation method, called multi-resolution Ganssian mixture model method, is proposed. First, an image pyramid is constructed and son-father link relationship is built between each level of pyramid. Then the mixture model segmentation method is applied to the top level. The segmentation result on the top level is passed top-down to the bottom level according to the son-father link relationship between levels. The proposed method considers not only local but also global information of image, it overcomes the effect of noise and can obtain better segmentation result. Experimental result demonstrates its effectiveness. 展开更多
关键词 image segmentation multi-RESOLUTION Ganssian mixture model.
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Multi-Focus Image Fusion Based on Wavelet Transformation 被引量:4
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作者 Peng Zhang Ying-Xun Tang +1 位作者 Yan-Hua Liang Xu-Bo Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第2期124-128,共5页
In the fusion of image,how to measure the local character and clarity is called activity measurement. According to the problem,the traditional measurement is decided only by the high-frequency detail coefficients, whi... In the fusion of image,how to measure the local character and clarity is called activity measurement. According to the problem,the traditional measurement is decided only by the high-frequency detail coefficients, which will make the energy expression insufficient to reflect the local clarity. Therefore,in this paper,a novel construction method for activity measurement is proposed. Firstly,it uses the wavelet decomposition for the fusion resource image, and then utilizes the high and low frequency wavelet coefficients synthetically. Meantime,it takes the normalized variance as the weight of high-frequency energy. Secondly,it calculates the measurement by the weighted energy,which can be used to measure the local character. Finally,the fusion coefficients can be got. In order to illustrate the superiority of this new method,three kinds of assessing indicators are provided. The experiment results show that,comparing with the traditional methods,this new method weakens the fuzzy and promotes the indicator value. Therefore,it has much more advantages for practical application. 展开更多
关键词 variance MEASURE image fusion wavelet transformation multi-resolution analysis
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3D FEM simulation of responses of LWD multi-mode resistivity imaging sonde 被引量:4
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作者 Kang Zheng-Ming Ke Shi-Zhen +3 位作者 Li Xin Mi Jin-Tai Ni Wei-Ning Li Ming-Yu 《Applied Geophysics》 SCIE CSCD 2018年第3期401-412,共12页
A new multi-mode resistivity imaging sonde, with toroidal coils as source, can conduct three resistivity measurements: azimuthal resistivity, lateral resistivity, and bit resistivity measurements. Thus, the logging ti... A new multi-mode resistivity imaging sonde, with toroidal coils as source, can conduct three resistivity measurements: azimuthal resistivity, lateral resistivity, and bit resistivity measurements. Thus, the logging time and cost are greatly saved. The toroidal coils are simplified as an extended voltage dipole and the response equations are derived for a homogenous formation. Based on 3D FEM, the depth of investigation(DOI), vertical resolution, circumferential azimuthal capacity, borehole diameter, mud resistivity, thickness of target formation, and the resistivity of the surrounding formation and mud invasion are simulated. The results suggest that the three measurement modes of the new sonde are different in vertical resolutions and DOIs. The circumferential detection ability of the azimuth button depends on the contrast between the anomaly and formation resistivity and the open angle of the anomaly. Whether the borehole is truncated at the bit or not has a great influence on the simulation results. The borehole and mud invasion affect the apparent resistivity in all modes, but the effects of resistivity of surrounding formation and thickness of the target formation are only corrected for lateral resistivity measurement. 展开更多
关键词 3D FEM LWD multi-MODE RESISTIVITY imaging detection characteristics ENVIRONMENTAL effects
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