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An Empirical Bayes Approach to Robust Variance Estimation: A Statistical Proposal for Quantitative Medical Image Testing 被引量:1
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作者 Zhan-Qian John Lu Charles Fenimore +1 位作者 Ronald H Gottlieb Carl C. Jaffe 《Open Journal of Statistics》 2012年第3期260-268,共9页
The current standard for measuring tumor response using X-ray, CT and MRI is based on the response evaluation criterion in solid tumors (RECIST) which, while providing simplifications over previous (WHO) 2-D methods, ... The current standard for measuring tumor response using X-ray, CT and MRI is based on the response evaluation criterion in solid tumors (RECIST) which, while providing simplifications over previous (WHO) 2-D methods, stipulate four response categories: CR (complete response), PR (partial response), PD (progressive disease), SD (stable disease) based purely on percentage changes without consideration of any measurement uncertainty. In this paper, we propose a statistical procedure for tumor response assessment based on uncertainty measures of radiologist’s measurement data. We present several variance estimation methods using time series methods and empirical Bayes methods when a small number of serial observations are available on each member of a group of subjects. We use a publically available database which contains a set of over 100 CT scan images on 23 patients with annotated RECIST measurements by two radiologist readers. We show that despite of bias in each individual reader’s measurements, statistical decisions on tumor change can be made on each individual subject. The consistency of the two readers can be established based on the intra-reader change assessments. Our proposal compares favorably with the RECIST standard protocol, raising the hope that, statistically sound decision on change analysis can be made in future based on careful variability and measurement uncertainty analysis. 展开更多
关键词 RECIST QUANTITATIVE Imaging as a Biomarker CHANGE Analysis Lung CT image Measurement Inter-Reader and Intra-Reader Variability Time Series Variance ESTIMATION ESTIMATION of Many Variances STATISTICAL Decision Rule on CHANGE
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An Overview and Perspectives On Bidirectional Intelligence: Lmser Duality, Double IA Harmony,and Causal Computation 被引量:3
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作者 Lei Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期865-893,共29页
Advances on bidirectional intelligence are overviewed along three threads,with extensions and new perspectives.The first thread is about bidirectional learning architecture,exploring five dualities that enable Lmser s... Advances on bidirectional intelligence are overviewed along three threads,with extensions and new perspectives.The first thread is about bidirectional learning architecture,exploring five dualities that enable Lmser six cognitive functions and provide new perspectives on which a lot of extensions and particularlly flexible Lmser are proposed.Interestingly,either or two of these dualities actually takes an important role in recent models such as U-net,ResNet,and Dense Net.The second thread is about bidirectional learning principles unified by best yIng-yAng(IA)harmony in BYY system.After getting insights on deep bidirectional learning from a bird-viewing on existing typical learning principles from one or both of the inward and outward directions,maximum likelihood,variational principle,and several other learning principles are summarised as exemplars of the BYY learning,with new perspectives on advanced topics.The third thread further proceeds to deep bidirectional intelligence,driven by long term dynamics(LTD)for parameter learning and short term dynamics(STD)for image thinking and rational thinking in harmony.Image thinking deals with information flow of continuously valued arrays and especially image sequence,as if thinking was displayed in the real world,exemplified by the flow from inward encoding/cognition to outward reconstruction/transformation performed in Lmser learning and BYY learning.In contrast,rational thinking handles symbolic strings or discretely valued vectors,performing uncertainty reasoning and problem solving.In particular,a general thesis is proposed for bidirectional intelligence,featured by BYY intelligence potential theory(BYY-IPT)and nine essential dualities in architecture,fundamentals,and implementation,respectively.Then,problems of combinatorial solving and uncertainty reasoning are investigated from this BYY IPT perspective.First,variants and extensions are suggested for AlphaGoZero like searching tasks,such as traveling salesman problem(TSP)and attributed graph matching(AGM)that are turned into Go like problems with help of a feature enrichment technique.Second,reasoning activities are summarized under guidance of BYY IPT from the aspects of constraint satisfaction,uncertainty propagation,and path or tree searching.Particularly,causal potential theory is proposed for discovering causal direction,with two roads developed for its implementation. 展开更多
关键词 Autoencoder LMSER DUALITY outward attention associative recall concept formation imagining pattern transformation STD vs LTD RPCL skip connection feedback variational least redundancy Bayesian Ying Yang IA system best HARMONY best matching image THINKING rational THINKING INTELLIGENCE potential theory Alpha-TSP Alpha-AGM graph matching ME Player BYY Follower constraint satisfaction CAUSAL potential theory
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MRF-Based Multispectral Image Fusion Using an Adaptive Approach Based on Edge-Guided Interpolation 被引量:1
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作者 Mohammad Reza Khosravi Mohammad Sharif-Yazd +3 位作者 Mohammad Kazem Moghimi Ahmad Keshavarz Habib Rostami Suleiman Mansouri 《Journal of Geographic Information System》 2017年第2期114-125,共12页
In interpretation of remote sensing images, it is possible that some images which are supplied by different sensors become incomprehensible. For better visual perception of these images, it is essential to operate ser... In interpretation of remote sensing images, it is possible that some images which are supplied by different sensors become incomprehensible. For better visual perception of these images, it is essential to operate series of pre-processing and elementary corrections and then operate a series of main processing steps for more precise analysis on the images. There are several approaches for processing which are depended on the type of remote sensing images. The discussed approach in this article, i.e. image fusion, is the use of natural colors of an optical image for adding color to a grayscale satellite image which gives us the ability for better observation of the HR image of OLI sensor of Landsat-8. This process with emphasis on details of fusion technique has previously been performed;however, we are going to apply the concept of the interpolation process. In fact, we see many important software tools such as ENVI and ERDAS as the most famous remote sensing image processing tools have only classical interpolation techniques (such as bi-linear (BL) and bi-cubic/cubic convolution (CC)). Therefore, ENVI- and ERDAS-based researches in image fusion area and even other fusion researches often don’t use new and better interpolators and are mainly concentrated on the fusion algorithm’s details for achieving a better quality, so we only focus on the interpolation impact on fusion quality in Landsat-8 multispectral images. The important feature of this approach is to use a statistical, adaptive, and edge-guided interpolation method for improving the color quality in the images in practice. Numerical simulations show selecting the suitable interpolation techniques in MRF-based images creates better quality than the classical interpolators. 展开更多
关键词 Satellite image FUSION Statistical INTERPOLATION MULTISPECTRAL images Markov Random Field (MRF) Intensity-Hue-Saturation (IHS) image FUSION Technique Natural Sense Statistics (NSS) Linear Minimum Mean Square Error-Estimation (LMMSE)
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Deciphering of Space Images of the Inder Salt-Dome Upland in ENVI 4.7 Program
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作者 K. M. Akhmedenov A. G. Koshym R. Z. Zhumabekova 《International Journal of Geosciences》 2014年第3期286-295,共10页
Space images play an important role in the Earth study as they bring the main information received from the Space Flyer Units (SFU) to help researchers. Space images’ deciphering gives the opportunity to study the te... Space images play an important role in the Earth study as they bring the main information received from the Space Flyer Units (SFU) to help researchers. Space images’ deciphering gives the opportunity to study the territory and to plot different maps. On the basis of the space image obtained from Landsat 5TM (30 m resolution, 01.09.2012 year), we managed to get a picture of the modern relief of the northern part of Inder lake. When comparing the space image with topographic maps of 1985, we succeeded to identify the dynamics of landforms change on the studied area, what has been shown on the drawn map of the relief of the Inder salt dome uplift. 14 classes, corresponding to a particular type of terrain or to a landscape complex, have been distinguished on the studied area. Inder salt dome uplift is a paradynamic conjugation, consisting of highly karsted Inder Mountains corresponding to large diapir uplift, and of the Inder Lake having a large ellipsoidal shape. Geomorphologically, the investigated territory is located on the left bank of Zhaiyk River, and presents a salt dome uplift in the form of a plateau-like hill raised above the surrounding surface from 12 to 40 m. The maximum height reaches 42.5 m (g. Suatbaytau). The crest of the Inder salt dome is composed of Low Permian sediments (rock salt with anhydrite, potassiummagnesium salts), and has an area of about 210 km2. Inder lake’s basin is represented by a tectonic depression, which is the local basis of erosion and is a drainage place of the Inder uplift karstic water. The lake area is 150 km2. Depending on the climatic conditions, the water level can vary. 展开更多
关键词 Space image Inder Salt-Dome Uplift KARST RELIEF Exogenous PROCESSES KARST PROCESSES RELIEF Shapes Basis of Erosion Automated Deciphering Vector Layer Objects Classification Object Classes Landscapes Complex Mapping
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Image Mathematics—Mathematical Intervening Principle Based on “Yin Yang Wu Xing” Theory in Traditional Chinese Mathematics (I) 被引量:28
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作者 Yingshan Zhang Weilan Shao 《Applied Mathematics》 2012年第6期617-636,共20页
By using mathematical reasoning, this paper demonstrates the mathematical intervening principle: “Virtual disease is to fill his mother but real disease is to rush down his son” (虚则补其母, 实则泄其子) and “Strong... By using mathematical reasoning, this paper demonstrates the mathematical intervening principle: “Virtual disease is to fill his mother but real disease is to rush down his son” (虚则补其母, 实则泄其子) and “Strong inhibition of the same time, support the weak” (抑强扶弱) based on “Yin Yang Wu Xing” Theory in image mathematics of Traditional Chinese Mathematics (TCMath). We defined generalized relations and generalized reasoning, introduced the concept of steady multilateral systems with two non-compatibility relations, and discussed its energy properties. Later based on the intervention principle in image mathematics of TCMath and treated the research object of the image mathematics as a steady multilateral system, it has been proved that the mathematical intervening principle is true. The kernel of this paper is the existence and reasoning of the non-compatibility relations in steady multilateral systems, and it accords with the oriental thinking model. 展开更多
关键词 image MATHEMATICS Yin Yang WU Xing Theory Steady Multilateral Systems Opposite Non-Compatibility Relations INTERVENTION RULE Self-Protection RULE MATHEMATICAL Side Effects Mathe-matical INTERVENTION Resistance Problem
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Application of Different Image Processing Techniques on Aster and ETM+ Images for Exploration of Hydrothermal Alteration Associated with Copper Mineralizations Mapping Kehdolan Area (Eastern Azarbaijan Province-Iran) 被引量:2
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作者 Golchin Hajibapir Mohammad Lotfi +1 位作者 Afshar Zia Zarifi Nima Nezafati 《Open Journal of Geology》 2014年第11期582-597,共16页
The Kehdolan area is located at 20 kilometers to the?south-east of Dozdozan Town (Eastern Azarbaijan Province). According to structural geology, volconic rocks are situated in Alborz-Azarbyjan zone, and faults?are?obs... The Kehdolan area is located at 20 kilometers to the?south-east of Dozdozan Town (Eastern Azarbaijan Province). According to structural geology, volconic rocks are situated in Alborz-Azarbyjan zone, and faults?are?observed?in?the?same direction to this system with SE-NW trend. The results show that kaolinite alteration trend with Argilic and propylitic veins?is the?same direction with SW-NE faults in this area. Therefore, these faults with these trends can be considered as the mineralization control for determination of the alterations. Different image processing techniques,?such as false color composite?(FCC), band ratios, color ratio composite?(CRC), principal component?analysis?(PCA), Crosta technique, supervised spectral angle mapping?(SAM), are used for?identification of the alteration zones associated with copper mineralization. In this project ASTER?data are process and spectral analysis to fit for recognizing intensity and kind of argillic, propylitic,?philic, and ETM+ data?which?are process and to fit for iron oxide and relation to metal mineralization of the area. For recognizing different alterations of the study area, some chemical and mineralogical analysis data from the samples showed that ASTER data and ETM+ data were?capable of hydrothermal alteration mapping with copper mineralization.?Copper mineralization in the region is in agreement with argillic alteration. SW-NE trending faults controlled the mineralization process. 展开更多
关键词 Kehdolan Area False COLOR COMPOSITE Band Ratios COLOR Ratio COMPOSITE Principal Component Analysis Crosta Technique Supervised Spectral Angle MAPPING ASTER DATA ETM%PLUS% DATA Alteration
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Image Analysis in Microbiology: A Review 被引量:1
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作者 Evgeny Puchkov 《Journal of Computer and Communications》 2016年第15期8-32,共26页
This review is focused on using computer image analysis as a means of objective and quantitative characterizing optical images of the macroscopic (e.g. microbial colonies) and the microscopic (e.g. single cell) object... This review is focused on using computer image analysis as a means of objective and quantitative characterizing optical images of the macroscopic (e.g. microbial colonies) and the microscopic (e.g. single cell) objects in the microbiological research. This is the way of making many visual inspection assays more objective and less time and labor consuming. Also, it can provide new visually inaccessible information on relation between some optical parameters and various biological features of the microbial cul-tures. Of special interest is application of image analysis in fluorescence microscopy as it opens new ways of using fluorescence based methodology for single microbial cell studies. Examples of using image analysis in the studies of both the macroscopic and the microscopic microbiological objects obtained by various imaging techniques are presented and discussed. 展开更多
关键词 Computer image Analysis Microorganisms VIABILITY Yeast Bacteria Fungi Colony Counter Microbial Identification Multispectral Imaging Hyperspectral Imaging Diffraction Pattern Imaging Scatter Pattern Imaging Multifractal Analysis Support Vector Machines Principal Component Analysis Linear Discriminant Analysi imageJ Matlab Fluorescence Microscopy Microfluorimetry Green Fluorescent Protein (GFP)
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Computer-aided differential diagnosis system for Alzheimer’s disease based on machine learning with functional and morphological image features in magnetic resonance imaging
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作者 Yasuo Yamashita Hidetaka Arimura +7 位作者 Takashi Yoshiura Chiaki Tokunaga Ohara Tomoyuki Koji Kobayashi Yasuhiko Nakamura Nobuyoshi Ohya Hiroshi Honda Fukai Toyofuku 《Journal of Biomedical Science and Engineering》 2013年第11期1090-1098,共9页
Alzheimer’s disease (AD) is a dementing disorder and one of the major public health problems in countries with greater longevity. The cerebral cortical thickness and cerebral blood flow (CBF), which are considered as... Alzheimer’s disease (AD) is a dementing disorder and one of the major public health problems in countries with greater longevity. The cerebral cortical thickness and cerebral blood flow (CBF), which are considered as morphological and functional image features, respectively, could be decreased in specific cerebral regions of patients with dementia of Alzheimer type. Therefore, the aim of this study was to develop a computer-aided classification system for AD patients based on machine learning with the morphological and functional image features derived from a magnetic resonance (MR) imaging system. The cortical thicknesses in ten cerebral regions were derived as morphological features by using gradient vector trajectories in fuzzy membership images. Functional CBF maps were measured with an arterial spin labeling technique, and ten regional CBF values were obtained by registration between the CBF map and Talairach atlas using an affine transformation and a free form deformation. We applied two systems based on an arterial neural network (ANN) and a support vector machine (SVM), which were trained with 4 morphological and 6 functional image features, to 15 AD patients and 15 clinically normal (CN) subjects for classification of AD. The area under the receiver operating characteristic curve (AUC) values for the two systems based on the ANN and SVM with both image?features were 0.901 and 0.915, respectively. The AUC values for the ANN-and SVM-based systems with the morphological features were 0.710 and 0.660, respectively, and those with the functional features were 0.878 and 0.903, respectively. Our preliminary results suggest that the proposed method may have potential for assisting radiologists in the differential diagnosis of AD patients by using morphological and functional image features. 展开更多
关键词 COMPUTER-AIDED Classification (CAD) Alzheimers Disease Magnetic Resonance Imaging (MRI) Arterial Spin Labeling (ASL) Fuzzy MEMBERSHIP image Cortical Thickness Cerebral Blood Flow (CBF)
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Image Processing Tool Promoting Decision-Making in Liver Surgery of Patients with Chronic Kidney Disease
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作者 Kristina Bliznakova Nikola Kolev +4 位作者 Zhivko Bliznakov Ivan Buliev Anton Tonev Elitsa Encheva Krasimir Ivanov 《Journal of Software Engineering and Applications》 2014年第2期118-127,共10页
Preoperative assessment of the liver volume and function of the remnant liver is a mandatory prerequisite before performing major hepatectomy. The aim of this work is to develop and test a software application for eva... Preoperative assessment of the liver volume and function of the remnant liver is a mandatory prerequisite before performing major hepatectomy. The aim of this work is to develop and test a software application for evaluation of the residual function of the liver prior to the intervention of the surgeons. For this purpose, a complete software platform consisting of three basic modules: liver volume segmentation, visualization, and virtual cutting, was developed and tested. Liver volume segmentation is based on a patient examination with non-contrast abdominal Computed Tomography (CT). The basis of the segmentation is a multiple seeded region growing algorithm adapted for use with CT images without contrast-enhancement. Virtual tumor resection is performed interactively by outlining the liver region on the CT images. The software application then processes the results to produce a three-dimensional (3D) image of the “resected” region. Finally, 3D rendering module provides possibility for easy and fast interpretation of the segmentation results. The visual outputs are accompanied with quantitative measures that further provide estimation of the residual liver function and based on them the surgeons could make a better decision. The developed system was tested and verified with twenty abdominal CT patient sets consisting of different numbers of tomographic images. Volumes, obtained by manual tracing of two surgeon experts, showed a mean relative difference of 4.5%. The application was used in a study that demonstrates the need and the added value of such a tool in practice and in education. 展开更多
关键词 Non-Contrast Enhanced COMPUTED Tomography images Evaluation of the Residual Function of the LIVER LIVER Segmentation Seeded Regional Growing Algorithm Virtual Tumor RESECTION DECISION-MAKING Educational TOOL
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Detection of ocean internal waves based on Faster R-CNN in SAR images 被引量:5
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作者 BAO Sude MENG Junmin +1 位作者 SUN Lina LIU Yongxin 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第1期55-63,共9页
Ocean internal waves appear as irregular bright and dark stripes on synthetic aperture radar(SAR)remote sensing images.Ocean internal waves detection in SAR images consequently constituted a difficult and popular rese... Ocean internal waves appear as irregular bright and dark stripes on synthetic aperture radar(SAR)remote sensing images.Ocean internal waves detection in SAR images consequently constituted a difficult and popular research topic.In this paper,ocean internal waves are detected in SAR images by employing the faster regions with convolutional neural network features(Faster R-CNN)framework;for this purpose,888 internal wave samples are utilized to train the convolutional network and identify internal waves.The experimental results demonstrate a 94.78%recognition rate for internal waves,and the average detection speed is 0.22 s/image.In addition,the detection results of internal wave samples under different conditions are analyzed.This paper lays a foundation for detecting ocean internal waves using convolutional neural networks. 展开更多
关键词 ocean internal waves FASTER regions with convolutional NEURAL NETWORK features (Faster R-CNN) convolutional NEURAL NETWORK synthetic APERTURE radar (SAR) image region proposal NETWORK (RPN)
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Complexity estimation of image sequence for automatic target track
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作者 WANG Xiaotian ZHANG Kai YAN Jie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第4期672-683,共12页
In the field of automatic target recognition and tracking,traditional image complexity metrics,such as statistical variance and signal-to-noise ratio,all focus on single-frame images.However,there are few researches a... In the field of automatic target recognition and tracking,traditional image complexity metrics,such as statistical variance and signal-to-noise ratio,all focus on single-frame images.However,there are few researches about the complexity of image sequence.To solve this problem,a criterion of evaluating image sequence complexity is proposed.Firstly,to characterize this criterion quantitatively,two metrics for measuring the complexity of image sequence,namely feature space similarity degree of global background(FSSDGB)and feature space occultation degree of local background(FSODLB)are developed.Here,FSSDGB reflects the ability of global background to introduce false alarms based on feature space,and FSODLB represents the difference between target and local background based on feature space.Secondly,the feature space is optimized by the grey relational method and relevant features are removed so that FSSDGB and FSODLB are more reasonable to establish complexity of single-frame images.Finally,the image sequence complexity is not a linear sum of the single-frame image complexity.Target tracking errors often occur in high-complexity images and the tracking effect of low-complexity images is very well.The nonlinear transformation based on median(NTM)is proposed to construct complexity of image sequence.The experimental results show that the proposed metric is more valid than other metrics,such as sequence correlation(SC)and interframe change degree(IFCD),and it is highly relevant to the actual performance of automatic target tracking algorithms. 展开更多
关键词 COMPLEXITY of image sequence FEATURE SPACE similarity DEGREE of global background(FSSDGB) FEATURE SPACE OCCULTATION DEGREE of local background(FSODLB) grey relational method nonlinear transformation based on median(NTM)
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New Results in Perceptually Lossless Compression of Hyperspectral Images
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作者 Chiman Kwan Jude Larkin 《Journal of Signal and Information Processing》 2019年第3期96-124,共29页
Hyperspectral images (HSI) have hundreds of bands, which impose heavy burden on data storage and transmission bandwidth. Quite a few compression techniques have been explored for HSI in the past decades. One high perf... Hyperspectral images (HSI) have hundreds of bands, which impose heavy burden on data storage and transmission bandwidth. Quite a few compression techniques have been explored for HSI in the past decades. One high performing technique is the combination of principal component analysis (PCA) and JPEG-2000 (J2K). However, since there are several new compression codecs developed after J2K in the past 15 years, it is worthwhile to revisit this research area and investigate if there are better techniques for HSI compression. In this paper, we present some new results in HSI compression. We aim at perceptually lossless compression of HSI. Perceptually lossless means that the decompressed HSI data cube has a performance metric near 40 dBs in terms of peak-signal-to-noise ratio (PSNR) or human visual system (HVS) based metrics. The key idea is to compare several combinations of PCA and video/ image codecs. Three representative HSI data cubes were used in our studies. Four video/image codecs, including J2K, X264, X265, and Daala, have been investigated and four performance metrics were used in our comparative studies. Moreover, some alternative techniques such as video, split band, and PCA only approaches were also compared. It was observed that the combination of PCA and X264 yielded the best performance in terms of compression performance and computational complexity. In some cases, the PCA + X264 combination achieved more than 3 dBs than the PCA + J2K combination. 展开更多
关键词 Hyperspectral images (HSI) Compression Perceptually LOSSLESS Principal Component Analysis (PCA) Human Visual System (HVS) PSNR SSIM JPEG-2000 X264 X265 Daala
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Congruent Feature Selection Method to Improve the Efficacy of Machine Learning-Based Classification in Medical Image Processing
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作者 Mohd Anjum Naoufel Kraiem +2 位作者 Hong Min Ashit Kumar Dutta Yousef Ibrahim Daradkeh 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期357-384,共28页
Machine learning(ML)is increasingly applied for medical image processing with appropriate learning paradigms.These applications include analyzing images of various organs,such as the brain,lung,eye,etc.,to identify sp... Machine learning(ML)is increasingly applied for medical image processing with appropriate learning paradigms.These applications include analyzing images of various organs,such as the brain,lung,eye,etc.,to identify specific flaws/diseases for diagnosis.The primary concern of ML applications is the precise selection of flexible image features for pattern detection and region classification.Most of the extracted image features are irrelevant and lead to an increase in computation time.Therefore,this article uses an analytical learning paradigm to design a Congruent Feature Selection Method to select the most relevant image features.This process trains the learning paradigm using similarity and correlation-based features over different textural intensities and pixel distributions.The similarity between the pixels over the various distribution patterns with high indexes is recommended for disease diagnosis.Later,the correlation based on intensity and distribution is analyzed to improve the feature selection congruency.Therefore,the more congruent pixels are sorted in the descending order of the selection,which identifies better regions than the distribution.Now,the learning paradigm is trained using intensity and region-based similarity to maximize the chances of selection.Therefore,the probability of feature selection,regardless of the textures and medical image patterns,is improved.This process enhances the performance of ML applications for different medical image processing.The proposed method improves the accuracy,precision,and training rate by 13.19%,10.69%,and 11.06%,respectively,compared to other models for the selected dataset.The mean error and selection time is also reduced by 12.56%and 13.56%,respectively,compared to the same models and dataset. 展开更多
关键词 Computer vision feature selection machine learning region detection texture analysis image classification medical images
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Smart Photogrammetric and Remote Sensing Image Processing for Very High Resolution Optical Images——Examples from the CRC-AGIP Lab at UNB 被引量:6
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作者 Yun ZHANG 《Journal of Geodesy and Geoinformation Science》 2019年第2期17-26,共10页
This paper introduces some of the image processing techniques developed in the Canada Research Chair in Advanced Geomatics Image Processing Laboratory (CRC-AGIP Lab) and in the Department of Geodesy and Geomatics Engi... This paper introduces some of the image processing techniques developed in the Canada Research Chair in Advanced Geomatics Image Processing Laboratory (CRC-AGIP Lab) and in the Department of Geodesy and Geomatics Engineering (GGE) at the University of New Brunswick (UNB), Canada. The techniques were developed by innovatively/“smartly” utilizing the characteristics of the available very high resolution optical remote sensing images to solve important problems or create new applications in photogrammetry and remote sensing. The techniques to be introduced are: automated image fusion (UNB-PanSharp), satellite image online mapping, street view technology, moving vehicle detection using single set satellite imagery, supervised image segmentation, image matching in smooth areas, and change detection using images from different viewing angles. Because of their broad application potential, some of the techniques have made a global impact, and some have demonstrated the potential for a global impact. 展开更多
关键词 remote sensing optical image very high resolution pan-sharpening online mapping STREET view moving information DETECTION image segmentation image MATCHING change DETECTION
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An Approach to Fault Diagnosis of Rotating Machinery Using the Second-Order Statistical Features of Thermal Images and Simplified Fuzzy ARTMAP
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作者 Faisal Al Thobiani Van Tung Tran Tiedo Tinga 《Engineering(科研)》 2017年第6期524-539,共16页
Thermal image, or thermogram, becomes a new type of signal for machine condition monitoring and fault diagnosis due to the capability to display real-time temperature distribution and possibility to indicate the mach... Thermal image, or thermogram, becomes a new type of signal for machine condition monitoring and fault diagnosis due to the capability to display real-time temperature distribution and possibility to indicate the machine’s operating condition through its temperature. In this paper, an investigation of using the second-order statistical features of thermogram in association with minimum redundancy maximum relevance (mRMR) feature selection and simplified fuzzy ARTMAP (SFAM) classification is conducted for rotating machinery fault diagnosis. The thermograms of different machine conditions are firstly preprocessed for improving the image contrast, removing noise, and cropping to obtain the regions of interest (ROIs). Then, an enhanced algorithm based on bi-dimensional empirical mode decomposition is implemented to further increase the quality of ROIs before the second-order statistical features are extracted from their gray-level co-occurrence matrix (GLCM). The highly relevant features to the machine condition are selected from the total feature set by mRMR and are fed into SFAM to accomplish the fault diagnosis. In order to verify this investigation, the thermograms acquired from different conditions of a fault simulator including normal, misalignment, faulty bearing, and mass unbalance are used. This investigation also provides a comparative study of SFAM and other traditional methods such as back-propagation and probabilistic neural networks. The results show that the second-order statistical features used in this framework can provide a plausible accuracy in fault diagnosis of rotating machinery. 展开更多
关键词 Thermal images SECOND-ORDER Statistical Features Gray-Level CO-OCCURRENCE Matrix Minimum Redundancy Maximum RELEVANCE Rotating Machinery Fault Diagnosis Simplified Fuzzy ARTMAP
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Body Image Disturbance and Dissatisfaction, Scorn and Stigma in Severely Obese Individuals, a Case-Control Study
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作者 M. Koski H. Naukkarinen 《Open Journal of Psychiatry》 2018年第3期355-375,共21页
Background: The obesity rate is rising. The aims of this study were to elucidate the connection among body image disturbance and dissatisfaction, scorn and stigma in severely obese individuals using a case-control met... Background: The obesity rate is rising. The aims of this study were to elucidate the connection among body image disturbance and dissatisfaction, scorn and stigma in severely obese individuals using a case-control method. Method: The study group consisted of 112 individuals receiving permanent disability pensions primarily for obesity. The controls were selected by random sampling. The controls were matched with the subjects by place of residence, gender, age, the time since the pension was granted and occupation. Psychiatric interviews and psychological assessments were conducted with all participants. The results were analyzed via chi-squared tests (χ2-tests) and percent distributions. The subject and control groups were compared via paired t-tests. Conditional logistic regression analysis was also conducted. Results: In the Draw a Person test, we found disorganization of the body image to some degree in the subject group. Some significant differences were found between the Machover index and the wholeness index. The Rorschach variables obtained some differences in the responses between the subject and control groups. Obesity was a problem in all age groups. In the study group, half of the participants thought that they were obese. Most of the participants had endured scorn and contempt directed at them due to being overweight. Conclusions: We believe that our study provides a novel and necessary overview of the connection among body image disturbance and dissatisfaction, scorn and stigma. 展开更多
关键词 BODY DISSATISFACTION BODY image BMI Draw a Person Machover INDEX Obesity Overweight RORSCHACH Variable Scorn STIGMA WEIGHT Misperception WEIGHT Perception Wholeness INDEX
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Image-based brachytherapy for cervical cancer 被引量:7
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作者 John A Vargo Sushil Beriwal 《World Journal of Clinical Oncology》 CAS 2014年第5期921-930,共10页
Cervical cancer is the third most common cancer in women worldwide; definitive radiation therapy and concurrent chemotherapy is the accepted standard of care for patients with node positive or locally advanced tumors ... Cervical cancer is the third most common cancer in women worldwide; definitive radiation therapy and concurrent chemotherapy is the accepted standard of care for patients with node positive or locally advanced tumors > 4 cm. Brachytherapy is an important part of definitive radiotherapy shown to improve overall survival. While results for two-dimensional X-ray based brachytherapy have been good in terms of local control especially for early stage disease, unexplained toxicities and treatment failures remain. Improvements in brachytherapy planning have more recently paved the way for three-dimensional image-based brachytherapy with volumetric optimization which increases tumor control, reduces toxicity, and helps predict outcomes.Advantages of image-based brachytherapy include:improved tumor coverage(especially for large volume disease), decreased dose to critical organs(especially for small cervix), confirmation of applicator placement, and accounting for sigmoid colon dose. A number of modalities for image-based brachytherapy have emerged including: magnetic resonance imaging(MRI),computed tomography(CT), CT-MRI hybrid, and ultrasound with respective benefits and outcomes data. Forpractical application of image-based brachytherapy the Groupe Europeen de Curietherapie-European Society for Therapeutic Radiology and Oncology Working Group and American Brachytherapy Society working group guideline serve as invaluable tools, additionally here-in we outline our institutional clinical integration of these guidelines. While the body of literature supporting image-based brachytherapy continues to evolve a number of uncertainties and challenges remain including: applicator reconstruction, increasing resource/cost demands, mobile four-dimensional targets and organs-at-risk, and accurate contouring of "grey zones" to avoid marginal miss. Ongoing studies, including the prospective EMBRACE(an international study of MRI-guided brachytherapy in locally advanced cervical cancer) trial, along with continued improvements in imaging, contouring, quality assurance, physics, and brachytherapy delivery promise to perpetuate the advancement of image-based brachytherapy to optimize outcomes for cervical cancer patients. 展开更多
关键词 CERVICAL cancer BRACHYTHERAPY imagebased BRACHYTHERAPY 3D-planning Magnetic resonance imaging-based BRACHYTHERAPY Groupe Europeen de Curietherapie-European Society for Therapeutic RADIOLOGY and ONCOLOGY Working Group guidelines
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航天湍流退化图像的极大似然估计规整化复原算法 被引量:24
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作者 洪汉玉 张天序 余国亮 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2005年第2期130-134,共5页
为了从有噪的湍流退化图像中有效地恢复出目标图像,提出了一种基于极大似然估计准则的规整化复原算法.根据图像随机场模型建立了有关多帧图像数据的对数似然函数,同时为了平滑噪声和保护图像边缘以及避免无价值的解,将一些合理的惩罚项... 为了从有噪的湍流退化图像中有效地恢复出目标图像,提出了一种基于极大似然估计准则的规整化复原算法.根据图像随机场模型建立了有关多帧图像数据的对数似然函数,同时为了平滑噪声和保护图像边缘以及避免无价值的解,将一些合理的惩罚项和辅助平滑项融合到该对数似然函数中.推导出了湍流点扩展函数和目标图像的交替迭代求解公式,通过迭代方式可将点扩展函数和目标图像同时估计出来,给出了算法的并行处理方案.在微机上对强噪声条件下的湍流退化图像进行了恢复实验,实验结果表明本算法具有较强的抗噪能力和实用价值. 展开更多
关键词 退
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有限宽板孔边弹塑性变形测试 被引量:6
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作者 张天林 薛炳 +1 位作者 朱金花 何世平 《实验力学》 CSCD 北大核心 2005年第1期97-101,共5页
测量应变集中区域的弹塑性变形,对于研究材料损伤或微裂纹的产生,以预防宏观裂纹的产生及扩展具有重要的意义。为给航空发动机轮盘的损伤容限设计研究提供相关材料的力学实验参数,做了两个有限宽中心带孔试件的拉伸试验。试验中,采用单... 测量应变集中区域的弹塑性变形,对于研究材料损伤或微裂纹的产生,以预防宏观裂纹的产生及扩展具有重要的意义。为给航空发动机轮盘的损伤容限设计研究提供相关材料的力学实验参数,做了两个有限宽中心带孔试件的拉伸试验。试验中,采用单调逐级加、卸载的循环加载方式,并应用自动网格法和数字图像相关技术测量了孔周的全场位移分布。再应用最小二乘法将离散的位移分量拟合成二元多项式函数,求解出拉伸方向的应变分布,并给出孔边应力σ与孔边应变εy的关系曲线。 展开更多
关键词 线
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No-reference image quality assessment based on AdaBoost_BP neural network in wavelet domain 被引量:1
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作者 YAN Junhua BAI Xuehan +4 位作者 ZHANG Wanyi XIAO Yongqi CHATWIN Chris YOUNG Rupert BIRCH Phil 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第2期223-237,共15页
Considering the relatively poor robustness of quality scores for different types of distortion and the lack of mechanism for determining distortion types, a no-reference image quality assessment(NR-IQA) method based o... Considering the relatively poor robustness of quality scores for different types of distortion and the lack of mechanism for determining distortion types, a no-reference image quality assessment(NR-IQA) method based on the Ada Boost BP neural network in the wavelet domain(WABNN) is proposed. A 36-dimensional image feature vector is constructed by extracting natural scene statistics(NSS) features and local information entropy features of the distorted image wavelet sub-band coefficients in three scales. The ABNN classifier is obtained by learning the relationship between image features and distortion types. The ABNN scorer is obtained by learning the relationship between image features and image quality scores. A series of contrast experiments are carried out in the laboratory of image and video engineering(LIVE) database and TID2013 database. Experimental results show the high accuracy of the distinguishing distortion type, the high consistency with subjective scores and the high robustness of the method for distorted images. Experiment results also show the independence of the database and the relatively high operation efficiency of this method. 展开更多
关键词 image quality assessment (IQA) AdaBoost_BP neural network (ABNN) WAVELET transform natural SCENE STATISTICS (NSS) local information ENTROPY
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