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Assessment and Visualization of Ki67 Heterogeneity in Breast Cancers through Digital Image Analysis
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作者 Chien-Hui Wu Min-Hsiang Chang +1 位作者 Hsin-Hsiu Tsai Yi-Ting Peng 《Advances in Breast Cancer Research》 CAS 2024年第2期11-26,共16页
The Ki67 index (KI) is a standard clinical marker for tumor proliferation;however, its application is hindered by intratumoral heterogeneity. In this study, we used digital image analysis to comprehensively analyze Ki... The Ki67 index (KI) is a standard clinical marker for tumor proliferation;however, its application is hindered by intratumoral heterogeneity. In this study, we used digital image analysis to comprehensively analyze Ki67 heterogeneity and distribution patterns in breast carcinoma. Using Smart Pathology software, we digitized and analyzed 42 excised breast carcinoma Ki67 slides. Boxplots, histograms, and heat maps were generated to illustrate the KI distribution. We found that 30% of cases (13/42) exhibited discrepancies between global and hotspot KI when using a 14% KI threshold for classification. Patients with higher global or hotspot KI values displayed greater heterogenicity. Ki67 distribution patterns were categorized as randomly distributed (52%, 22/42), peripheral (43%, 18/42), and centered (5%, 2/42). Our sampling simulator indicated analyzing more than 10 high-power fields was typically required to accurately estimate global KI, with sampling size being correlated with heterogeneity. In conclusion, using digital image analysis in whole-slide images allows for comprehensive Ki67 profile assessment, shedding light on heterogeneity and distribution patterns. This spatial information can facilitate KI surveys of breast cancer and other malignancies. 展开更多
关键词 Ki67 Heterogeneity Breast Cancer digital image analysis
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Collagen proportionate area of liver tissue determined by digital image analysis in patients with HBV-related decompensated cirrhosis 被引量:1
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作者 Shi-Bin Xie, Chao Ma, Chao-Shuang Lin,Ying Zhang, Jian-Yun Zhu and Wei-Min Ke Department of Infectious Disease, Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510630, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2011年第5期497-501,共5页
BACKGROUND: The accurate assessment of the degree of hepatic fibrosis plays a critical role in guiding the diagnosis, treatment and prognostic assessment of chronic liver diseases. Liver biopsy is currently the most r... BACKGROUND: The accurate assessment of the degree of hepatic fibrosis plays a critical role in guiding the diagnosis, treatment and prognostic assessment of chronic liver diseases. Liver biopsy is currently the most reliable method to evaluate the severity of hepatic fibrosis. However, liver biopsy is an invasive procedure associated with morbidity and mortality, and has several limitations in patients with decompensated cirrhosis. There is no report on the collagen proportionate area (CPA) of liver tissue in the decompensated stage of cirrhosis. This study aimed to determine the CPA of resected liver tissue samples from patients with HBV-related decompensated cirrhosis using digital image analysis, and to analyze the relationship between the CPA and liver functional reserve. METHODS: Fifty-three resected liver tissue samples from liver transplant patients with chronic hepatitis B-induced decompensated cirrhosis were stained with Masson’s trichrome, and the CPA in these samples was quantitatively determined using digital image analysis. The values of relevant liver function just before liver transplantation, the CPA in liver tissue, and their correlation were analyzed. RESULTS: The mean CPA at the decompensated stage of cirrhosis was 35.93±14.42% (11.24%-63.41%). The correlation coefficients of the CPA with a model for end-stage liver disease score, serum total bilirubin and international standard ratio of prothrombin B were 0.553, 0.519 and 0.533, respectively (P<0.001). With increasing CPA values, the three indices reflecting liver functional reserve also changed significantly.CONCLUSIONS: The degree of fibrosis may be correlated with the functional reserve. With the advancement of fibrosis, the liver functional reserve is attenuated accordingly. 展开更多
关键词 collagen proportionate area digital image analysis decompensated cirrhosis chronic hepatitis B
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DIGITAL IMAGE ANALYSIS OF PHASE STRUCTURE IN THE BLEND OF POLY(BUTYLENE TEREPHTHALATE-COCAPROLACTONE) WITH POLYCARBONATE
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作者 马德柱 贺丽玲 +3 位作者 邹应芳 罗筱烈 Takafumi Hayashi Toshio Nishi 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第1期44-48,共5页
The digital image processing technique was used for the extraction of physical information from the temporal image of phase structure in the process of phase separation in the blend of poly (butylene terephthalate-co-... The digital image processing technique was used for the extraction of physical information from the temporal image of phase structure in the process of phase separation in the blend of poly (butylene terephthalate-co-caprolactone )with polycarbonate. The power spectrum images of the two-dimensional Fourier transformation (2DFT) of the temporal image of phase structure reflect the change of the phase size with time. 展开更多
关键词 digital image analysis Phase structure Fourier transformation Wave vector BCL copolymer
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Impact of blurs on machine-learning aided digital pathology image analysis
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作者 Maki Ogura Tomoharu Kiyuna Hiroshi Yoshida 《Artificial Intelligence in Cancer》 2020年第1期31-38,共8页
BACKGROUND Digital pathology image(DPI)analysis has been developed by machine learning(ML)techniques.However,little attention has been paid to the reproducibility of ML-based histological classification in heterochron... BACKGROUND Digital pathology image(DPI)analysis has been developed by machine learning(ML)techniques.However,little attention has been paid to the reproducibility of ML-based histological classification in heterochronously obtained DPIs of the same hematoxylin and eosin(HE)slide.AIM To elucidate the frequency and preventable causes of discordant classification results of DPI analysis using ML for the heterochronously obtained DPIs.METHODS We created paired DPIs by scanning 298 HE stained slides containing 584 tissues twice with a virtual slide scanner.The paired DPIs were analyzed by our MLaided classification model.We defined non-flipped and flipped groups as the paired DPIs with concordant and discordant classification results,respectively.We compared differences in color and blur between the non-flipped and flipped groups by L1-norm and a blur index,respectively.RESULTS We observed discordant classification results in 23.1%of the paired DPIs obtained by two independent scans of the same microscope slide.We detected no significant difference in the L1-norm of each color channel between the two groups;however,the flipped group showed a significantly higher blur index than the non-flipped group.CONCLUSION Our results suggest that differences in the blur-not the color-of the paired DPIs may cause discordant classification results.An ML-aided classification model for DPI should be tested for this potential cause of the reduced reproducibility of the model.In a future study,a slide scanner and/or a preprocessing method of minimizing DPI blur should be developed. 展开更多
关键词 Machine learning digital pathology image Automated image analysis BLUR COLOR REPRODUCIBILITY
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<i>In Vitro</i>Bioassay of Allelopathy in Four Bamboo Species;<i>Bambusa multiplex, Phyllostachys bambusoides, P. nigra, Sasa kurilensis</i>, Using Sandwich Method and Protoplast Co-Culture Method with Digital Image Analysis 被引量:4
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作者 Shinjiro Ogita Hamako Sasamoto 《American Journal of Plant Sciences》 2017年第7期1699-1710,共12页
Moderately strong allelopathic activities were found in four bamboo species, Bambusa multiplex cv. Houraichiku;Phyllostachys bambusoides cv. Madake;P. nigra cv. Hachiku;Sasa kurilensis cv. Chishimazasa, which are of d... Moderately strong allelopathic activities were found in four bamboo species, Bambusa multiplex cv. Houraichiku;Phyllostachys bambusoides cv. Madake;P. nigra cv. Hachiku;Sasa kurilensis cv. Chishimazasa, which are of different classification or of different ecological distributions, using the “Sandwich Method”, which assays the dried leaves on growth of lettuce seedlings. Only small difference of activity was found among the four bamboo species. In addition, “Protoplast Co-culture Method” for assay of allelopathy in a 50 μL liquid medium using a 96 well culture plate, was applied to the suspension cultures of the four bamboo species. Protoplasts were isolated from two-week cultured suspension cells of four bamboo species using Cellulase RS and Pectolyase Y-23 in 0.6 M mannitol. At low protoplast densities of bamboo, B. multiplex and P. bambusoides stimulated the recipient lettuce growth, i.e., non-spherically cell enlargement and cell divisions observed under an inverted microscope, while protoplasts of P. nigra and S. kurilensis were less stimulatory or inhibitory. Inhibitory effect of S. kurilensis was the strongest among four bamboo species. Furthermore, highly inhibitory effects of S. kurilensis protoplasts on yellow color accumulation of lettuce protoplasts were clearly observed by analysis of a scanned digital image of a 96-well culture plate. Differences and causes of the allelopathic activities were discussed comparing with other plant species studied using the same assay methods. 展开更多
关键词 ALLELOPATHY Bamboo BIOASSAY digital image analysis PROTOPLAST Culture
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An image analysis method for quantification of hepatic perfusion based on contrast-enhanced ultrasound imaging
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作者 Yi-xin Li Fang Yang Ning Gu 《Journal of Biomedical Science and Engineering》 2008年第2期116-120,共5页
Information about hepatic perfusion is used in clinical liver disease diagnosis. An image analy-sis system can help physicians make efficient and accurate diagnosis. The objective of this study is to propose an image ... Information about hepatic perfusion is used in clinical liver disease diagnosis. An image analy-sis system can help physicians make efficient and accurate diagnosis. The objective of this study is to propose an image analysis method for the quantification of the hepatic perfusion based on contrast-enhanced ultrasound imaging (CEUI). The proposed method contains frame selection, image registration, digital subtraction and grey-scale calculation. Then, by processing an image sequence, a time-intensity curve (TIC) for hepatic perfusion is derived. The kernel of this image analysis technology is digital subtrac-tion and its accuracy is improved by frame selec-tion and image registration. The advantage of this method is that it can obtain the perfusion information of the whole liver which is rarely ob-tained by traditional image analysis technology;therefore, it is a supplement of the traditional image analysis method. This method is applied on the quantification of a rabbit’s hepatic perfu-sion and the result shows the efficiency of it. 展开更多
关键词 HEPATIC PERFUSION quantification image analysis image REGISTRATION digital SUBTRACTION
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Automated Detection and Quantification of Prostate Cancer in Needle Biopsies by Digital Image Analysis
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作者 Vamsi Parimi Laurie J. Eisengart Ximing J. Yang 《Open Journal of Pathology》 2014年第3期138-150,共13页
Introduction: Triple immunohistochemical (IHC) stains including antibodies specific for alpha-methylacyl-CoA-racemase and basal cell markers have been a valuable aid in accurate identification of prostate carcinoma. H... Introduction: Triple immunohistochemical (IHC) stains including antibodies specific for alpha-methylacyl-CoA-racemase and basal cell markers have been a valuable aid in accurate identification of prostate carcinoma. However, accurate quantification of minuscule areas of prostate carcinoma in biopsy specimens can often be a challenge. Here we assessed the diagnostic value and quantitative use of automated digital image analysis on triple IHC stained prostate needle biopsies. Methods: Twelve cases of prostate needle biopsy material including 75 needle cores were stained with triple-antibody cocktail (P504S + 34βE12 + p63). Slides were digitally scanned with the APERIO digital image analyzer and evaluated with the GENIE pattern and color recognition digital image analysis that we developed. A slide with known areas of adenocarcinoma, high grade prostatic intraepithelial neoplasia (PIN), benign glands and stroma was used as a training set for the automated digital image analysis platform. Results: Among 75 needle biopsy cores, 19 (25.33%) contained adenocarcinoma by histology. Digital image analysis recognized adenocarcinoma in 95% of these needle biopsies. The average area of the needle biopsy was 7.63 mm2 and overall the average area of tumor was 0.196 mm2. The smallest area of tumor recognized by the program was 0.0022 mm2 (0.0363% of the core) and the largest was 0.62 mm2 (8.17% of the core) among needle core biopsies. False positives resulted from areas of high grade PIN with patchy basal cells. The false negative was caused by uneven AMACR staining in one area of adenocarcinoma. Digital recognition of areas of interest was improved by three successive image analysis training which increased the sensitivity and specificity from 83% and 89% to 90% and 93%, respectively. Conclusions: Digital image analysis in concert with IHC triple staining may be useful for accurate detection and quantitative analysis of small foci of prostatic adenocarcinoma. Defining methods to increase the sensitivity and specificity of quantitative automated digital image analysis will likely evolve as an area of investigation. Future automated digital scanning and innovative pattern and color recognition technologies may open avenues for classifying a variety of prostate lesions. 展开更多
关键词 PROSTATIC Adenocarcinoma NEEDLE Biopsy Alpha-Methylacyl-CoA-Racemase P504S Basal Cell Immunohistochemistry Automated digital image analysis
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Bubble dynamics properties of B-particles in a quasi-2D gas-solid fluidized bed:Computational particle fluid dynamics numerical simulation and post-processed by digital image analysis technique
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作者 Zemin Yuan Zhong Huang +4 位作者 Guotao Qin Guanjia Zhao Suxia Ma Hairui Yang Guangxi Yue 《Particuology》 SCIE EI CAS CSCD 2024年第3期223-238,共16页
Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-t... Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-two-dimensional(quasi-2D)fluidized bed,including bubble equivalent diameter,bubble size distribution,average bubble density,bubble aspect ratio,bubble hold-up,bed expansion ratio,bubble radial position,and bubble velocity.The studies were performed by computational particle fluid dynamics(CPFD)numerical simulation and post-processed with digital image analysis(DIA)technique,at superficial gas velocities ranging from 2u_(mf) to 7u_(mf).The simulated results shown that the CPFD simulation combining with DIA technique post-processing could be used as a reliable method for simulating bubble dynamics properties in quasi-2D gas-solid fluidized beds.However,it seemed not desirable for the simulation of bubble motion near the air distributor at higher superficial gas velocity from the simulated average bubble density distribution.The superficial gas velocity significantly affected the bubble equivalent diameter and evolution,while it had little influence on bubble size distribution and bubble aspect ratio distribution for the same particles.Both time-averaged bubble hold-up and bed expansion ratio increased with the increase of superficial gas velocity.Two core-annular flow structures could be found in the fluidized bed for all cases.The average bubble rising velocity increased with the increasing bubble equivalent diameter.For bubble lateral movement,the smaller bubbles might be more susceptible,and superficial gas velocity had a little influence on the absolute lateral velocity of bubbles.The simulated results presented a valuable and novel approach for studying bubble dynamics properties.The comprehensive understanding of bubble dynamics behaviors in quasi-2D gas-solid fluidized beds would provide support in the design,operation,and optimization of gas-solid fluidized bed reactors. 展开更多
关键词 Bubble dynamics properties CPFD simulation Quasi-2D gas-solid fluidized bed digital image analysis
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Estimation of Ground Deformation Caused by the Earthquake (M7.2) in Japan,2008,from the Geomorphic Image Analysis of High Resolution LiDAR DEMs 被引量:2
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作者 MUKOYAMA Sakae 《Journal of Mountain Science》 SCIE CSCD 2011年第2期239-245,共7页
In this study, a new method for quantitative and efficient measurement for the ground surface movement was developed. The feature of this technique is to identify geomorphic characteristics by image matching analysis,... In this study, a new method for quantitative and efficient measurement for the ground surface movement was developed. The feature of this technique is to identify geomorphic characteristics by image matching analysis, using the intelligent images made from high resolution DEM(Digital Elevation Model). This method is useful to extract the small ground displacement where the surface shape was not intensely deformed. 展开更多
关键词 Ground deformation Ground surface movement digital Elevation Model(DEM) Geomorphic image analysis JAPAN
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Research on the Multimedia Information Retrieval Algorithm based on Information Restructuring and Image Reconstruction
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作者 Nian Li 《International Journal of Technology Management》 2016年第3期36-39,共4页
In this paper, we conduct research on the multimedia information retrieval algorithm based on the information restructuring and image reconstruction. With the massive growth of information resources, people through va... In this paper, we conduct research on the multimedia information retrieval algorithm based on the information restructuring and image reconstruction. With the massive growth of information resources, people through various retrieval tools for too much information, led directly to information overload. In vector space model and probability retrieval model based on information retrieval tools rarely consider the user' s personalized information needs and features, has resulted in a large amount of information retrieval result and correlation information the user' s information demand is not big. In order to improve the existing retrieval system, in recent years, scholars to study looked that context information retrieval context factors need to be considered, such as the retrieval time, place and the interactive history, mission, environment and other factors stated or implied in the retrieval process. At present, the context research has become the information behavior, information search process and the research hotspot in the field of information retrieval interaction. 展开更多
关键词 multimedia Information Retrieval Algorithm image Reconstruction Data analysis.
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Simulation of Fracture Process of Lightweight Aggregate Concrete Based on Digital Image Processing Technology
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作者 Safwan Al-sayed Xi Wang Yijiang Peng 《Computers, Materials & Continua》 SCIE EI 2024年第6期4169-4195,共27页
The mechanical properties and failure mechanism of lightweight aggregate concrete(LWAC)is a hot topic in the engineering field,and the relationship between its microstructure and macroscopic mechanical properties is a... The mechanical properties and failure mechanism of lightweight aggregate concrete(LWAC)is a hot topic in the engineering field,and the relationship between its microstructure and macroscopic mechanical properties is also a frontier research topic in the academic field.In this study,the image processing technology is used to establish a micro-structure model of lightweight aggregate concrete.Through the information extraction and processing of the section image of actual light aggregate concrete specimens,the mesostructural model of light aggregate concrete with real aggregate characteristics is established.The numerical simulation of uniaxial tensile test,uniaxial compression test and three-point bending test of lightweight aggregate concrete are carried out using a new finite element method-the base force element method respectively.Firstly,the image processing technology is used to produce beam specimens,uniaxial compression specimens and uniaxial tensile specimens of light aggregate concrete,which can better simulate the aggregate shape and random distribution of real light aggregate concrete.Secondly,the three-point bending test is numerically simulated.Thirdly,the uniaxial compression specimen generated by image processing technology is numerically simulated.Fourth,the uniaxial tensile specimen generated by image processing technology is numerically simulated.The mechanical behavior and damage mode of the specimen during loading were analyzed.The results of numerical simulation are compared and analyzed with those of relevant experiments.The feasibility and correctness of the micromodel established in this study for analyzing the micromechanics of lightweight aggregate concrete materials are verified.Image processing technology has a broad application prospect in the field of concrete mesoscopic damage analysis. 展开更多
关键词 digital image processing lightweight aggregate concrete mesoscopic model numerical simulation fracture analysis bending beams
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In-situ strain measurement and error analysis of arc welding with 2D digital image correlation 被引量:1
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作者 Huang Honghao Hu Minghua +2 位作者 Xu Aijie Song Yulin Chen Huabin 《China Welding》 CAS 2022年第3期17-23,共7页
The deformation and residual stress generated by the welding process can seriously affect the use of components.As a result,it is very important to understand the evolution of stress and strain during the welding proc... The deformation and residual stress generated by the welding process can seriously affect the use of components.As a result,it is very important to understand the evolution of stress and strain during the welding process.The strain measurement method based on digital image correlation(DIC)is an excellent method to detect welding strain and residual stress.The out-of-plane translation and out-of-plane rotation introduce errors to the two-dimensional DIC.In this paper,the causes of errors are analyzed theoretically,and the formulas of errors caused by the out-of-plane displacement and the out-of-plane rotation are derived.The out-of-plane translation experiment and the out-of-plane rotation experiment were carried out to verify the theory,and the experimental results are consistent with the theoretical analysis results.The error caused by the out-of-plane translation can be reduced by increasing the object distance;the error caused by the out-of-plane rotation is greatly affected by the rotation angle. 展开更多
关键词 arc welding digital image correlation strain measurement error analysis
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Automatic Computer Analysis of Digital Images of Triple-Antibody-Stained Prostate Biopsies
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作者 Erik Wilander Manuel de la Torre +2 位作者 Ursula Wilhelmsson ren Nygren 《Open Journal of Urology》 2021年第1期17-29,共13页
<strong>Background:</strong> Worldwide, prostatic adenocarcinoma is the most common tumour type among men. <strong>Aim:</strong> The aim of the present investigation was to develop a computer p... <strong>Background:</strong> Worldwide, prostatic adenocarcinoma is the most common tumour type among men. <strong>Aim:</strong> The aim of the present investigation was to develop a computer program to identify normal prostate biopsies and distinguish them from biopsies showing premalignant alterations (LGPIN, HGPIN) and adenocarcinoma. <strong>Method:</strong> Prostate biopsies (n = 2094) taken from 191 consecutive men during 2016 were stained with triple immunehistochemisty (antibodies to AMACRA, p63 and CK 5). Digital images of the biopsies were obtained with a scanning microscope and used to develop an automatic computer program (CelldaTM), intended to identify the morphological alterations. Visual microscopic finding was used as a reference. <strong>Result:</strong> Of the 191 men, 121 (63.4%) were diagnosed as having prostate adenocarcinoma and 70 (36.6%) as having no malignancy on the basis of the visual microscopy. In comparison, computer analysis identified 134 (70.2%) men with malignant disease and 57 (29.8%) with non-malignant disease after exclusion of artifacts, which constituted 10.4% of areas (indicated as malignant disease). Discrepant results were recorded in 15 (7.9%) men, and in 14 of these cases, HGPIN and areas suggestive of early invasion were common. Thus, it was uncertain whether these cases should be regarded as malignant or not. The agreement between the visual examination and the computer analysis was 92.1% (kappa value 0.823, sensitivity 99.2 and specificity was 0.80). <strong>Conclusion:</strong> It seems that computer analysis could serve as an adjunct to simplify and shorten the diagnostic procedure, first of all by ensuring that normal prostate biopsies are sorted out from those sent for visual microscopic evaluation. 展开更多
关键词 PROSTATE ADENOCARCINOMA LGPIN HGPIN ANTIBODY Computer digital images AUTOMATIC analysis AMACR P504S Microscopy Scanning
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HYBRID OPTICAL-DIGITAL IMAGE ANALYSIS SYSTEM AND ITS POTENTIAL APPLICATION TO OCEAN-WAVE HEIGHT MEASUREMENT
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作者 徐建华 庄青 +3 位作者 何永保 章志鸣 刘智深 贺明霞 《Science China Mathematics》 SCIE 1989年第10期1228-1236,共9页
This paper presents a hybrid optical-digital image analysis system (HODIAS), performing function of power spectrum sampling, optimal feature selection and classification. The results of experiments on two kinds of oce... This paper presents a hybrid optical-digital image analysis system (HODIAS), performing function of power spectrum sampling, optimal feature selection and classification. The results of experiments on two kinds of ocean wave heights with 0.1-m difference are satisfactory, The system may extend to multl-height automated measurement. 展开更多
关键词 HYBRID optical-digital image analysis feature selection classification ocean-wave height.
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Image compression scheme based on PCA for wireless multimedia sensor networks
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作者 Zhou Wei Sun Lijuan +1 位作者 Guo Jian Liu Linfeng 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2016年第1期22-30,共9页
In combination of the characteristic of the network architecture of wireless multimedia sensor networks (WMSNs), a distributed multi-node cooperative network (DMCN) model is designed by using the concept of in-net... In combination of the characteristic of the network architecture of wireless multimedia sensor networks (WMSNs), a distributed multi-node cooperative network (DMCN) model is designed by using the concept of in-network processing to improve their energy, memory and computational power. To balance the energy consumption of the network, according to roles division, camera nodes and common nodes are cooperated to accomplish the workload of image acquisition, compression and transmission. Camera nodes gather images and send blocking images to the common nodes in cluster. Common nodes adaptively compress the partitioned images by using a noise-tolerant distributed image compression (NDIC) algorithm based on principal component analysis (PCA) called NDIC-PCA algorithm and send the compressed data to the cluster head node. Then, the cluster head node sends the compressed image data to the station. Simulation results demonstrate that, DCNM can effectively balance the energy consumption of network and largely extend the network lifecycle. In addition, compared with previous algorithms, the proposed NDIC-PCA algorithm achieves higher peak signal to noise ratio without decreasing compression ratio. 展开更多
关键词 wireless multimedia sensor networks image compression principal component analysis node collaboration
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A Thorough Investigation on Image Forgery Detection
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作者 Anjani Kumar Rai Subodh Srivastava 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期1489-1528,共40页
Image forging is the alteration of a digital image to conceal some of the necessary or helpful information.It cannot be easy to distinguish themodified region fromthe original image in somecircumstances.The demand for... Image forging is the alteration of a digital image to conceal some of the necessary or helpful information.It cannot be easy to distinguish themodified region fromthe original image in somecircumstances.The demand for authenticity and the integrity of the image drive the detection of a fabricated image.There have been cases of ownership infringements or fraudulent actions by counterfeiting multimedia files,including re-sampling or copy-moving.This work presents a high-level view of the forensics of digital images and their possible detection approaches.This work presents a thorough analysis of digital image forgery detection techniques with their steps and effectiveness.These methods have identified forgery and its type and compared it with state of the art.This work will help us to find the best forgery detection technique based on the different environments.It also shows the current issues in other methods,which can help researchers find future scope for further research in this field. 展开更多
关键词 Forgery detection digital forgery image forgery localization image segmentation image forensics multimedia security
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On Secure Digital Image Watermarking Techniques 被引量:2
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作者 Manjit Thapa Sandeep Kumar Sood 《Journal of Information Security》 2011年第4期169-184,共16页
Digital watermarking is used to hide the information inside a signal, which can not be easily extracted by the third party. Its widely used application is copyright protection of digital information. It is different f... Digital watermarking is used to hide the information inside a signal, which can not be easily extracted by the third party. Its widely used application is copyright protection of digital information. It is different from the encryption in the sense that it allows the user to access, view and interpret the signal but protect the ownership of the content. One of the current research areas is to protect digital watermark inside the information so that ownership of the information cannot be claimed by third party. With a lot of information available on various search engines, to protect the ownership of information is a crucial area of research. In latest years, several digital watermarking techniques are presented based on discrete cosine transform (DCT), discrete wavelets transform (DWT) and discrete fourier transforms (DFT). In this paper, we propose an algorithm for digital image watermarking technique based on singular value decomposition;both of the L and U components are explored for watermarking algorithm. This technique refers to the watermark embedding algorithm and watermark extracting algorithm. The experimental results prove that the quality of the watermarked image is excellent and there is strong resistant against many geometrical attacks. 展开更多
关键词 digital image WATERMARKING SINGULAR Value Decomposition WATERMARK Embedding ALGORITHM WATERMARK EXTRACTING ALGORITHM Ratio analysis Security analysis
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Arterial Imaging in Digital Gangrenes Associated with Scleroderma-Spectrum Disorders 被引量:1
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作者 Naoko Nagata Atsushi Tanemura +5 位作者 Hiroki Higashihara Yorihisa Kotobuki Hiroyuki Murota Mamori Tani Ken Igawa Ichiro Katayama 《Open Journal of Rheumatology and Autoimmune Diseases》 2012年第2期21-25,共5页
Objectives: Digital refractory gangrene is rarely found in collagen diseases, including systemic sclerosis and is possibly caused by similar underlying vascular damage in peripheral arterial disease (PAD) such as arte... Objectives: Digital refractory gangrene is rarely found in collagen diseases, including systemic sclerosis and is possibly caused by similar underlying vascular damage in peripheral arterial disease (PAD) such as arteriosclerosis obliterans (ASO) and/or thromboangiitis obliterans (TAO) by unclarified mechanisms other than vasculitis and thrombosis. This study evaluated the radiological imaging in patients with digital gangrene associated with collagen disease and compared the images with those of PAD based on the results of laboratory and histopathological examinations. Methods: Angiography, MR angiography and/or CT angiography were performed on 6 patients with refractory gangrene or extensive ulcers accompanied by scleroderma-spectrum disorders;3 with diffuse systemic sclerosis, 1 with limited systemic sclerosis, 1 with overlap syndrome and 1 with Sj?gren’s syndrome. Results: Although the vascular alterations in collagen diseases were similar to those in PAD, the abnormal image findings (occlusion or stenosis of the arteries with smooth vessel walls) found in collagen diseases did not include atheromatous plaque, which are worm-like vessels that are characteristic of those observed in PAD. Conclusions: Some cases of digital gangrene seen in collagen diseases show similar vascular imaging patterns to those of PAD and comprehensive examinations including arterial imaging can be useful for the diagnosis of these unrecognized vascular changes other than vasculitis or digital thrombosis. 展开更多
关键词 ARTERIAL imaging analysis digital Gangrene Scleroderma-Spectrum DISORDERS
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岩土材料中冰分布状态的冷冻电镜表征方法
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作者 王子振 王晓康 +3 位作者 申凯翔 苏捷 赵志强 周卫东 《实验室研究与探索》 CAS 北大核心 2024年第2期8-12,114,共6页
为从微观角度定量描述冰在岩土材料中的分布特征,基于冷冻电镜技术提出了一种微观尺度的实验表征方法。针对不同冰饱和度人造岩芯样品的二次电子图像和能谱分析图,通过元素含量分布、升华前后图像对比确认了冰在岩土材料中的分布状态。... 为从微观角度定量描述冰在岩土材料中的分布特征,基于冷冻电镜技术提出了一种微观尺度的实验表征方法。针对不同冰饱和度人造岩芯样品的二次电子图像和能谱分析图,通过元素含量分布、升华前后图像对比确认了冰在岩土材料中的分布状态。随着冰饱和度的增加,骨架孔隙被冰填充、骨架颗粒表面被冰包裹区域增大,样品断面更密实平整,岩土骨架的堆积结构特征变弱。在背散射电子图像中,冰的图像比岩土骨架亮度低、灰度高,基于此构建了冰饱和度的数字图像计算方法。该方法计算的升华前冰饱和度与样品预制冰饱和度偏差小于5%,验证了其可靠性。 展开更多
关键词 岩土材料 冷冻电镜 冰分布状态 数字图像分析
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基于临床CT数字体相关和有限元分析的股骨内部变形场研究 被引量:1
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作者 王家宁 符绩智 +2 位作者 冯文天 宋霏 杨海胜 《北京生物医学工程》 2024年第1期9-14,42,共7页
目的验证基于临床CT的数字体相关(digital volume correlation,DVC)方法在测量股骨内部变形场时的准确性,并通过DVC进一步测量股骨在跌倒情况下的内部变形,验证基于临床CT的有限元分析方法(finite element analysis,FEA)在计算股骨内部... 目的验证基于临床CT的数字体相关(digital volume correlation,DVC)方法在测量股骨内部变形场时的准确性,并通过DVC进一步测量股骨在跌倒情况下的内部变形,验证基于临床CT的有限元分析方法(finite element analysis,FEA)在计算股骨内部变形场的准确性。方法使用猪股骨,模拟侧向跌倒姿态,进行分步力学加载实验,同步进行多次CT成像。通过重复扫描和虚拟位移验证DVC方法的准确性。DVC以子体积作为配准两组图像的研究对象,分别设置8、12、16和20 mm的子体积进行测试。量化误差指标包括位移系统误差-平均值(mean)、位移随机误差-标准差(standard deviation,SD)、应变准确度-平均绝对误差(mean absolute error,MAER)和应变精确度-标准差误差(standard deviation of the error,SDER)。基于CT图像建立股骨有限元模型,模拟实验条件,计算股骨内部位移,与DVC测量的内部变形场对比验证。结果基于临床CT的DVC方法重复扫描位移偏差小于0.013 mm,MAER和SDER均小于200με;虚拟位移偏差小于0.098 mm,MAER为1093~1687με,SDER为604~1267με,远小于骨组织屈服应变。FEA计算的位移和DVC测量的位移之间具有较强的相关性(R^(2)≥0.76,P<0.05)。结论基于临床CT的DVC方法可以准确测量股骨内部变形场,并且基于临床CT的有限元模型可以准确计算股骨内部变形场。 展开更多
关键词 CT图像 有限元分析 数字体相关 骨质疏松 股骨骨折
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