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Image Segmentation Based on Support Vector Machine 被引量:6
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作者 徐海祥 朱光喜 +2 位作者 田金文 张翔 彭复员 《Journal of Electronic Science and Technology of China》 2005年第3期226-230,共5页
Image segmentation is a necessary step in image analysis. Support vector machine (SVM) approach is proposed to segment images and its segmentation performance is evaluated. Experimental results show that: the effec... Image segmentation is a necessary step in image analysis. Support vector machine (SVM) approach is proposed to segment images and its segmentation performance is evaluated. Experimental results show that: the effects of kernel function and model parameters on the segmentation performance are significant; SVM approach is less sensitive to noise in image segmentation; The segmentation performance of SVM approach is better than that of back-propagation multi-layer perceptron (BP-MLP) approach and fuzzy c-means (FCM) approach. 展开更多
关键词 support vector machine image segmentation image analysis
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Geometric active contour based approach for segmentation of high-resolution spaceborne SAR images 被引量:2
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作者 Shaoming Zhang Fang He +3 位作者 Yunling Zhang Jianmei Wang Xiao Mei Tiantian Feng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期69-76,共8页
Segmentation is the key step in auto-interpretation of high-resolution spaceborne synthetic aperture radar(SAR) images. A novel method is proposed based on integrating the geometric active contour(GAC) and the sup... Segmentation is the key step in auto-interpretation of high-resolution spaceborne synthetic aperture radar(SAR) images. A novel method is proposed based on integrating the geometric active contour(GAC) and the support vector machine(SVM)models. First, the images are segmented by using SVM and textural statistics. A likelihood measurement for every pixel is derived by using the initial segmentation. The Chan-Vese model then is modified by adding two items: the likelihood and the distance between the initial segmentation and the evolving contour. Experimental results using real SAR images demonstrate the good performance of the proposed method compared to several classic GAC models. 展开更多
关键词 image segmentation synthetic aperture radar(SAR) imagery support vector machine(SVM) geometric active contour(GAC)
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A Feature Selection Strategy to Optimize Retinal Vasculature Segmentation 被引量:3
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作者 Jose Escorcia-Gutierrez Jordina Torrents-Barrena +4 位作者 Margarita Gamarra Natasha Madera Pedro Romero-Aroca Aida Valls Domenec Puig 《Computers, Materials & Continua》 SCIE EI 2022年第2期2971-2989,共19页
Diabetic retinopathy (DR) is a complication of diabetesmellitus thatappears in the retina. Clinitians use retina images to detect DR pathologicalsigns related to the occlusion of tiny blood vessels. Such occlusion bri... Diabetic retinopathy (DR) is a complication of diabetesmellitus thatappears in the retina. Clinitians use retina images to detect DR pathologicalsigns related to the occlusion of tiny blood vessels. Such occlusion brings adegenerative cycle between the breaking off and the new generation of thinnerand weaker blood vessels. This research aims to develop a suitable retinalvasculature segmentation method for improving retinal screening proceduresby means of computer-aided diagnosis systems. The blood vessel segmentationmethodology relies on an effective feature selection based on SequentialForward Selection, using the error rate of a decision tree classifier in theevaluation function. Subsequently, the classification process is performed bythree alternative approaches: artificial neural networks, decision trees andsupport vector machines. The proposed methodology is validated on threepublicly accessible datasets and a private one provided by Hospital Sant Joanof Reus. In all cases we obtain an average accuracy above 96% with a sensitivityof 72% in the blood vessel segmentation process. Compared with the state-ofthe-art, our approach achieves the same performance as other methods thatneed more computational power.Our method significantly reduces the numberof features used in the segmentation process from 20 to 5 dimensions. Theimplementation of the three classifiers confirmed that the five selected featureshave a good effectiveness, independently of the classification algorithm. 展开更多
关键词 Diabetic retinopathy artificial neural networks decision trees support vector machines feature selection retinal vasculature segmentation
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Improvement of Liver Segmentation by Combining High Order Statistical Texture Features with Anatomical Structural Features 被引量:2
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作者 Suhuai Luo Xuechen Li Jiaming Li 《Engineering(科研)》 2013年第5期67-72,共6页
Automatic segmentation of liver in medical images is challenging on the aspects of accuracy, automation and robustness. A crucial stage of the liver segmentation is the selection of the image features for the segmenta... Automatic segmentation of liver in medical images is challenging on the aspects of accuracy, automation and robustness. A crucial stage of the liver segmentation is the selection of the image features for the segmentation. This paper presents an accurate liver segmentation algorithm. The approach starts with a texture analysis which results in an optimal set of texture features including high order statistical texture features and anatomical structural features. Then, it creates liver distribution image by classifying the original image pixelwisely using support vector machines. Lastly, it uses a group of morphological operations to locate the liver organ accurately in the image. The novelty of the approach is resided in the fact that the features are so selected that both local and global texture distributions are considered, which is important in liver organ segmentation where neighbouring tissues and organs have similar greyscale distributions. Experiment results of liver segmentation on CT images using the proposed method are presented with performance validation and discussion. 展开更多
关键词 LIVER segmentation TEXTURE FEATURE support VECTOR machine MORPHOLOGICAL Operation
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Defocus Blur Segmentation Using Genetic Programming and Adaptive Threshold 被引量:1
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作者 Muhammad Tariq Mahmood 《Computers, Materials & Continua》 SCIE EI 2022年第3期4867-4882,共16页
Detection and classification of the blurred and the non-blurred regions in images is a challenging task due to the limited available information about blur type,scenarios and level of blurriness.In this paper,we propo... Detection and classification of the blurred and the non-blurred regions in images is a challenging task due to the limited available information about blur type,scenarios and level of blurriness.In this paper,we propose an effective method for blur detection and segmentation based on transfer learning concept.The proposed method consists of two separate steps.In the first step,genetic programming(GP)model is developed that quantify the amount of blur for each pixel in the image.The GP model method uses the multiresolution features of the image and it provides an improved blur map.In the second phase,the blur map is segmented into blurred and non-blurred regions by using an adaptive threshold.A model based on support vector machine(SVM)is developed to compute adaptive threshold for the input blur map.The performance of the proposed method is evaluated using two different datasets and compared with various state-of-the-art methods.The comparative analysis reveals that the proposed method performs better against the state-of-the-art techniques. 展开更多
关键词 Blur measure blur segmentation sharpness measure genetic programming support vector machine
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Defocus Blur Segmentation Using Local Binary Patterns with Adaptive Threshold 被引量:1
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作者 Usman Ali Muhammad Tariq Mahmood 《Computers, Materials & Continua》 SCIE EI 2022年第4期1597-1611,共15页
Enormousmethods have been proposed for the detection and segmentation of blur and non-blur regions of the images.Due to the limited available information about blur type,scenario and the level of blurriness,detection ... Enormousmethods have been proposed for the detection and segmentation of blur and non-blur regions of the images.Due to the limited available information about blur type,scenario and the level of blurriness,detection and segmentation is a challenging task.Hence,the performance of the blur measure operator is an essential factor and needs improvement to attain perfection.In this paper,we propose an effective blur measure based on local binary pattern(LBP)with adaptive threshold for blur detection.The sharpness metric developed based on LBP used a fixed threshold irrespective of the type and level of blur,that may not be suitable for images with variations in imaging conditions,blur amount and type.Contrarily,the proposed measure uses an adaptive threshold for each input image based on the image and blur properties to generate improved sharpness metric.The adaptive threshold is computed based on the model learned through support vector machine(SVM).The performance of the proposed method is evaluated using two different datasets and is compared with five state-of-the-art methods.Comparative analysis reveals that the proposed method performs significantly better qualitatively and quantitatively against all of the compared methods. 展开更多
关键词 Adaptive threshold blur measure defocus blur segmentation local binary pattern support vector machine
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THE BENDING OF THIN RECTANGULAR PLATES WITH MIXED SUPPORTED SEGMENTS OF STRAIGHT EDGES
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作者 陈立志 付宝连 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第1期47-58,共12页
In this paper, the exact analytical solution of the rectangular plate having simplysupported segments mixed with free segments of straight edges are first given by means of the method of reciprocal theorem.By comparis... In this paper, the exact analytical solution of the rectangular plate having simplysupported segments mixed with free segments of straight edges are first given by means of the method of reciprocal theorem.By comparison .we calculate the same question by finite element method.Thecomparison shows that the analytical solution is correct. 展开更多
关键词 the method of reciprocal theorem. supported segment transfor-mation of trigonometric series
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SVM for density estimation and application to medical image segmentation
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作者 ZHANG Zhao ZHANG Su ZHANG Chen-xi CHEN Ya-zhu 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第5期365-372,共8页
A method of medical image segmentation based on support vector machine (SVM) for density estimation is presented. We used this estimator to construct a prior model of the image intensity and curvature profile of the s... A method of medical image segmentation based on support vector machine (SVM) for density estimation is presented. We used this estimator to construct a prior model of the image intensity and curvature profile of the structure from training images. When segmenting a novel image similar to the training images, the technique of narrow level set method is used. The higher dimensional surface evolution metric is defined by the prior model instead of by energy minimization function. This method offers several advantages. First, SVM for density estimation is consistent and its solution is sparse. Second, compared to the traditional level set methods, this method incorporates shape information on the object to be segmented into the segmentation process. Segmentation results are demonstrated on synthetic images, MR images and ultrasonic images. 展开更多
关键词 support vector machine (SVM) Density estimation Medical image segmentation Level set method
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Enhanced Wolf Pack Algorithm (EWPA) and Dense-kUNet Segmentation for Arterial Calcifications in Mammograms
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作者 Afnan M.Alhassan 《Computers, Materials & Continua》 SCIE EI 2024年第2期2207-2223,共17页
Breast Arterial Calcification(BAC)is a mammographic decision dissimilar to cancer and commonly observed in elderly women.Thus identifying BAC could provide an expense,and be inaccurate.Recently Deep Learning(DL)method... Breast Arterial Calcification(BAC)is a mammographic decision dissimilar to cancer and commonly observed in elderly women.Thus identifying BAC could provide an expense,and be inaccurate.Recently Deep Learning(DL)methods have been introduced for automatic BAC detection and quantification with increased accuracy.Previously,classification with deep learning had reached higher efficiency,but designing the structure of DL proved to be an extremely challenging task due to overfitting models.It also is not able to capture the patterns and irregularities presented in the images.To solve the overfitting problem,an optimal feature set has been formed by Enhanced Wolf Pack Algorithm(EWPA),and their irregularities are identified by Dense-kUNet segmentation.In this paper,Dense-kUNet for segmentation and optimal feature has been introduced for classification(severe,mild,light)that integrates DenseUNet and kU-Net.Longer bound links exist among adjacent modules,allowing relatively rough data to be sent to the following component and assisting the system in finding higher qualities.The major contribution of the work is to design the best features selected by Enhanced Wolf Pack Algorithm(EWPA),and Modified Support Vector Machine(MSVM)based learning for classification.k-Dense-UNet is introduced which combines the procedure of Dense-UNet and kU-Net for image segmentation.Longer bound associations occur among nearby sections,allowing relatively granular data to be sent to the next subsystem and benefiting the system in recognizing smaller characteristics.The proposed techniques and the performance are tested using several types of analysis techniques 826 filled digitized mammography.The proposed method achieved the highest precision,recall,F-measure,and accuracy of 84.4333%,84.5333%,84.4833%,and 86.8667%when compared to other methods on the Digital Database for Screening Mammography(DDSM). 展开更多
关键词 Breast arterial calcification cardiovascular disease semantic segmentation transfer learning enhanced wolf pack algorithm and modified support vector machine
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Osteosarcoma Segmentation in MRI Based on Zernike Moment and SVM
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作者 CHEN Chun-xiao ZHANG Dan +3 位作者 LI Ning QIAN Xiao-jun WU Shu-jia Gail Sudlow 《Chinese Journal of Biomedical Engineering(English Edition)》 2013年第2期70-78,共9页
Osteosarcoma is primary malignant neoplasms derived from cells of mesenchymal origin, and often has distinct phenotypes at different stages. The location of tumor and reaction zone can be identified by an expert in ma... Osteosarcoma is primary malignant neoplasms derived from cells of mesenchymal origin, and often has distinct phenotypes at different stages. The location of tumor and reaction zone can be identified by an expert in magnetic resonance imaging (MRI), with MRI being one of the choices for evaluating the extent of osteosarcoma. However, it is still a challenge to automatically extract tumor from its surrounding tissues because of their low intensity differences in MRI. We investigated an approach based on Zernike moment and support vector machine (SVM) for osteosarcoma segmentation in T1-weighted image (TIWI). Firstly, the different order moments around each pixel are calculated in small windows. Secondly, the grayscale and the module values of different order moments are used as a texture feature vector which is then used as the training set for SVM. Finally, an SVM classifier is trained based on this set of features to identify the osteosarcoma, and the segmented tumor tissue is rendered in 3D by the ray casting algorithm based on graphics processing unit (GPU). The performance of the method is validated on T1WI, showing that the segmentation method has a high similarity index with the expert's manual segmentation. 展开更多
关键词 OSTEOSARCOMA Zernike moment support vector machine (SVM) segmentation
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基于最优短时分数阶傅里叶变换的分段线性调频信号检测方法
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作者 范黎林 郭鑫 +1 位作者 张艳娜 李源 《探测与控制学报》 北大核心 2026年第1期89-97,共9页
目前基于时频分析技术的分段线性调频(LFM)信号检测方法,因不同时间段频率随时间动态变化差异,面临两大核心问题:一是交叉项干扰严重,影响信号检测准确性;二是时频分辨率受限于定性分析和固定搜索步长,难以灵活应对复杂多变的信号特性... 目前基于时频分析技术的分段线性调频(LFM)信号检测方法,因不同时间段频率随时间动态变化差异,面临两大核心问题:一是交叉项干扰严重,影响信号检测准确性;二是时频分辨率受限于定性分析和固定搜索步长,难以灵活应对复杂多变的信号特性。为解决上述问题,利用自适应短时分数阶傅里叶变换(STFRFT)技术,提出基于最优STFRFT的分段LFM信号检测方法。首先,从理论上建立窗长和分数阶与时频支撑区域之间精确的映射关系,以定量分析的方式弥补现有自适应STFRFT在解释时频质量提升方面的不足,避免交叉项干扰;其次,构建高效的STFRFT优化模型,并提出一种基于信号局部特性差异的“先粗后细”搜索策略,旨在提高时频分辨率优化算法效率,保证算法在处理复杂信号时的灵活性和准确性;最后,采用信息熵和运行时间作为算法性能衡量指标,在噪声环境下验证所提方法对分段LFM信号的检测性能。与其他时频分析方法对比,所提方法在提高分段LFM信号的时频分辨率方面表现出色,能够在较低的信噪比环境下显著提升分段LFM信号瞬时频率提取的鲁棒性。 展开更多
关键词 分段线性调频信号 自适应短时分数阶傅里叶变换 时频分辨率 支撑区域
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曲线段双护盾TBM隧道上穿既有隧道变形规律分析
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作者 檀俊坤 殷爱国 +3 位作者 乔世范 刘建伟 李二伟 翟乾智 《铁道科学与工程学报》 北大核心 2026年第1期208-222,共15页
新建隧道上穿既有隧道的直线段单护盾盾构施工对既有隧道环境影响已有许多研究,针对曲线段双护盾TBM隧道施工效应的研究还较少。首先,开展曲线段双护盾TBM隧道上穿既有隧道变形规律监测试验,发现双护盾TBM穿越既有隧道施工时,撑靴作用... 新建隧道上穿既有隧道的直线段单护盾盾构施工对既有隧道环境影响已有许多研究,针对曲线段双护盾TBM隧道施工效应的研究还较少。首先,开展曲线段双护盾TBM隧道上穿既有隧道变形规律监测试验,发现双护盾TBM穿越既有隧道施工时,撑靴作用对邻近既有隧道具有重要影响;曲线段管片受盾尾推力向外产生水平偏移,其偏移对围岩作用影响范围约距盾尾向后10 m内,偏移作用随与盾尾距离增大而增大。其次,分析了曲线段管片偏移与围岩相互作用,并基于Mindlin解构建了考虑卸荷应力、刀盘推力、盾壳摩擦力、撑靴支撑力、曲线段管片偏移作用及撑靴摩擦力共同作用的附加应力计算模型,基于Winkler地基模型推导了双护盾TBM新建隧道上穿既有隧道变形解析公式,并通过实例监测、有限元数值模拟的方法对解析公式进行验证及分析。此外,针对曲线段管片偏移作用、新建隧道与既有隧道净距、新建隧道推进距离等关键参数进行了既有隧道变形的影响分析。参数分析表明:直线段既有隧道的隆起变形位移关于新建隧道轴线对称,曲线段双护盾TBM隧道开挖对既有线影响区在距既有隧道轴线−1 m到15 m的范围内,隧道隆起变形随推进距离的增加表现为先增大后减小的规律,双护盾TBM隧道与既有隧道竖向间距越大,对既有隧道产生变形的影响越小;TBM撑靴推进至既有轴线正上方时,对既有隧道变形的影响最大;曲线段管片偏移作用,将使既有线隧道最大变形位置向外偏移。 展开更多
关键词 隧道工程 曲线段隧道 双护盾TBM 既有隧道变形 管片偏移 TBM撑靴 理论解析
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vivo全球AI研发中心钢结构施工关键技术研究
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作者 杨熙华 马洁烽 +3 位作者 赏莹莹 王相阁 吴楚桥 张之浩 《建筑钢结构进展》 北大核心 2026年第2期115-126,共12页
vivo全球AI研发中心为复杂钢框架-核心筒结构体系,建筑内含5道单截面箱形大跨度巨拱,巨拱最高39.0 m,最大跨度77.6 m。项目现场施工条件复杂,包含5层地下室,顶板层高差大、洞口多,施工最终选用了分段吊装法施工,实际工程中大型履带吊行... vivo全球AI研发中心为复杂钢框架-核心筒结构体系,建筑内含5道单截面箱形大跨度巨拱,巨拱最高39.0 m,最大跨度77.6 m。项目现场施工条件复杂,包含5层地下室,顶板层高差大、洞口多,施工最终选用了分段吊装法施工,实际工程中大型履带吊行驶至拱外侧钢栈桥,拱下方则搭设支撑系统,以自内向外的顺序进行施工。本文主要介绍了巨拱施工的方案选择思路,设计出了一种可供重型履带吊作业的钢栈桥以及以塔吊标准节为主的巨拱支撑系统,开展了巨拱全过程施工模拟分析和施工健康监测,二者进行对比后发现结果的吻合度较高;此外,本文还阐述了施工过程中工序配合等问题,对施工中异于常规超高层钢结构项目中的技术要点(如空间塔冠、临时塔吊附着等技术)进行了分析,可为后续同类超高层钢结构工程的实施提供一定的借鉴作用。 展开更多
关键词 箱形大跨度巨拱 分段吊装法 钢栈桥 支撑系统 施工模拟 超高层钢结构 临时塔吊附着
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基于自定函数的支持向量机电池故障诊断方法
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作者 蔡君同 刘尧 +1 位作者 雷南林 郝雄博 《中国汽车(中英文对照)》 2026年第3期149-156,共8页
随着电动汽车的普及,电池故障的准确诊断成为保障车辆安全和性能的重要环节。本文提出了一种基于分段网格搜索优化和自定义评分函数的支持向量回归(SVR)方法,用于电动车电池故障诊断。首先,通过数据清洗和切片对多台电动车1个月的运行... 随着电动汽车的普及,电池故障的准确诊断成为保障车辆安全和性能的重要环节。本文提出了一种基于分段网格搜索优化和自定义评分函数的支持向量回归(SVR)方法,用于电动车电池故障诊断。首先,通过数据清洗和切片对多台电动车1个月的运行数据进行处理,并提取关键特征参数。然后,利用皮尔森相关系数进行数据降维,简化数据集。接着,通过Min-Max标准化方法进行数据预处理,并采用分段网格搜索优化SVR模型参数。最后,设计自定义评分函数,从多个维度评估模型的预测效果。实验结果表明,该方法在故障识别准确率和预测精度方面表现出色,能够有效识别电池故障及其严重程度,为电动车电池故障诊断提供了可靠的技术支持。 展开更多
关键词 电动车电池 故障诊断 支持向量回归(SVR) 分段网格搜索 自定义评分函数 数据降维
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Human Behavior Classification Using Geometrical Features of Skeleton and Support Vector Machines 被引量:1
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作者 Syed Muhammad Saqlain Shah Tahir Afzal Malik +2 位作者 Robina khatoon SyedSaqlain Hassan Faiz Ali Shah 《Computers, Materials & Continua》 SCIE EI 2019年第8期535-553,共19页
Classification of human actions under video surveillance is gaining a lot of attention from computer vision researchers.In this paper,we have presented methodology to recognize human behavior in thin crowd which may b... Classification of human actions under video surveillance is gaining a lot of attention from computer vision researchers.In this paper,we have presented methodology to recognize human behavior in thin crowd which may be very helpful in surveillance.Research have mostly focused the problem of human detection in thin crowd,overall behavior of the crowd and actions of individuals in video sequences.Vision based Human behavior modeling is a complex task as it involves human detection,tracking,classifying normal and abnormal behavior.The proposed methodology takes input video and applies Gaussian based segmentation technique followed by post processing through presenting hole filling algorithm i.e.,fill hole inside objects algorithm.Human detection is performed by presenting human detection algorithm and then geometrical features from human skeleton are extracted using feature extraction algorithm.The classification task is achieved using binary and multi class support vector machines.The proposed technique is validated through accuracy,precision,recall and F-measure metrics. 展开更多
关键词 Human behavior classification segmentation human detection support vector machine
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An Intelligent Decision Support System for Lung Cancer Diagnosis
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作者 Ahmed A.Alsheikhy Yahia F.Said Tawfeeq Shawly 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期799-817,共19页
Lung cancer is the leading cause of cancer-related death around the globe.The treatment and survival rates among lung cancer patients are significantly impacted by early diagnosis.Most diagnostic techniques can identi... Lung cancer is the leading cause of cancer-related death around the globe.The treatment and survival rates among lung cancer patients are significantly impacted by early diagnosis.Most diagnostic techniques can identify and classify only one type of lung cancer.It is crucial to close this gap with a system that detects all lung cancer types.This paper proposes an intelligent decision support system for this purpose.This system aims to support the quick and early detection and classification of all lung cancer types and subtypes to improve treatment and save lives.Its algorithm uses a Convolutional Neural Network(CNN)tool to perform deep learning and a Random Forest Algorithm(RFA)to help classify the type of cancer present using several extracted features,including histograms and energy.Numerous simulation experiments were conducted on MATLAB,evidencing that this system achieves 98.7%accuracy and over 98%precision and recall.A comparative assessment assessing accuracy,recall,precision,specificity,and F-score between the proposed algorithm and works from the literature shows that the proposed system in this study outperforms existing methods in all considered metrics.This study found that using CNNs and RFAs is highly effective in detecting lung cancer,given the high accuracy,precision,and recall results.These results lead us to believe that bringing this kind of technology to doctors diagnosing lung cancer is critical. 展开更多
关键词 Lung cancer artificial intelligence CNN computer-aid diagnosis HISTOGRAM image segmentation decision support systemv
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高水平应力厚煤层巷道围岩变形机理及控制技术研究 被引量:2
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作者 霍丙杰 张海波 +3 位作者 吕华新 陈涛 张丞博 陈英震 《安全与环境学报》 北大核心 2025年第9期3493-3503,共11页
为解决高水平应力场中孤岛工作面回采巷道在掘进过程中围岩大变形问题,以新疆生产建设兵团塔什店联合矿业有限责任公司8303孤岛工作面回采巷道为研究对象,采用试验研究、数值模拟和现场试验等研究方法,从煤层质地、顶板特征、应力环境... 为解决高水平应力场中孤岛工作面回采巷道在掘进过程中围岩大变形问题,以新疆生产建设兵团塔什店联合矿业有限责任公司8303孤岛工作面回采巷道为研究对象,采用试验研究、数值模拟和现场试验等研究方法,从煤层质地、顶板特征、应力环境和孤岛开采等方面综合分析巷道变形机理。针对8303工作面回采巷道的地质条件,通过改变巷道围岩煤体强度分析其对巷道变形的影响,确定煤体强度与巷道承载能力呈线性关系;分析复合顶板离层导致锚索支护失效进而造成顶板下沉甚至冒顶的影响效应;以水平应力大小和是否为孤岛开采环境为变量,揭示巷道变形随水平应力的变化情况,得到孤岛开采的工作面比单一工作面的巷道变形更剧烈的机理;建立巷道在复杂应力条件下的力学模型。基于巷道变形机理,提出“锚杆(索)+金属网+全巷道分段架棚支护+局部补强支护”的联合支护形式。工业性试验表明优化后的支护方案有效地控制了巷道变形,围岩稳定性显著提升。 展开更多
关键词 安全工程 高水平应力巷道 变形机理 数值模拟 围岩控制 全巷道分段架棚支护
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带K形偏心支撑装配式混合框架抗震性能研究
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作者 张锡治 董泊君 +2 位作者 马相 陈再源 翟哲海 《天津大学学报(自然科学与工程技术版)》 北大核心 2025年第8期810-821,共12页
偏心支撑装配式混合框架是由预制混凝土柱、钢梁以及钢斜撑组成的双重抗侧体系.本文结合国内外对其的研究成果以及相关设计规范,研究带K形偏心支撑混合结构的抗震性能.混合框架的消能梁段采用屈服点较低的钢材(Q235)制作而成,基于此,对... 偏心支撑装配式混合框架是由预制混凝土柱、钢梁以及钢斜撑组成的双重抗侧体系.本文结合国内外对其的研究成果以及相关设计规范,研究带K形偏心支撑混合结构的抗震性能.混合框架的消能梁段采用屈服点较低的钢材(Q235)制作而成,基于此,对4个单层单跨带K形偏心支撑的装配式混合框架试件进行低周反复加载试验,分析不同因素对结构受力性能、变形发展和失效模式的影响,研究试件的破坏模式和主要抗震性能指标.研究结果表明:K型偏心支撑混合框架结构具有较好的承载力、延性性能以及耗能能力;消能梁段长度对结构整体承载力影响较大,楼板的存在能够提高结构的整体承载力;消能梁段作为K形偏心支撑混合框架的主要耗能构件,随结构变形发展,其先达到弹塑性状态,而其他钢梁、柱基本处于弹性状态、变形小,保证了结构的安全,抗震性能较好. 展开更多
关键词 K形偏心支撑 消能梁段 循环加载 承载力
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高强钢框架-Y形偏心支撑整体结构抗震性能分析
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作者 王峥 《西安轨道交通职业教育研究》 2025年第1期5-17,共13页
高强钢框架-Y形偏心支撑结构中耗能梁段竖向布置,与框架梁是独立的两个构件,截面设计更加灵活,且塑性变形对框架梁和楼板影响较小,易于震后修复。结构设计中耗能梁段设计为屈服点低于345MPa的普通钢材,保证整体结构具有较好的延性与耗能... 高强钢框架-Y形偏心支撑结构中耗能梁段竖向布置,与框架梁是独立的两个构件,截面设计更加灵活,且塑性变形对框架梁和楼板影响较小,易于震后修复。结构设计中耗能梁段设计为屈服点低于345MPa的普通钢材,保证整体结构具有较好的延性与耗能,框架梁、柱等非耗能构件设计为高强度钢材,如Q460或Q690,在保证非耗能构件的弹性受力状态基础上降低构件截面尺寸。耗能梁段长度和结构层数(结构高度)是影响该结构性能的主要因素,本文考虑两种因素的影响,通过性能化设计方法设计了8层、12层、16层三组高强钢框架-Y形偏心支撑原型结构,每组耗能梁段长度变化包括700mm、900mm和1100mm,共计9个模型。通过Pushover分析和动力弹塑性分析,研究了耗能梁段长度和结构层数对结构的破坏模式、刚度、层间侧移角分布、耗能梁段转角变形等影响。研究结果表明:耗能梁段越长,结构的抗侧刚度越弱;所有结构的层间侧移角和耗能梁段转角变形具有类似的分布模式。 展开更多
关键词 耗能梁段 结构层数 Y形偏心支撑 高强钢 层间侧移
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基于红外热成像的掘支锚机器人联合机组相对位姿检测方法研究 被引量:1
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作者 苏国用 帅洪锌 +3 位作者 郭永存 胡坤 赵东洋 庞子金 《煤炭学报》 北大核心 2025年第10期4640-4653,共14页
针对煤矿掘进工作面高尘雾、低照度复杂环境下,掘支锚机器人联合机组相对位姿感知存在的定位参照差、标定工序复杂、检测参数不完全等难题,提出了一种基于红外热成像的掘支锚机器人联合机组相对位姿检测方法。首先,基于自主研发的掘支... 针对煤矿掘进工作面高尘雾、低照度复杂环境下,掘支锚机器人联合机组相对位姿感知存在的定位参照差、标定工序复杂、检测参数不完全等难题,提出了一种基于红外热成像的掘支锚机器人联合机组相对位姿检测方法。首先,基于自主研发的掘支锚机器人联合机组,构建由红外热成像相机、热源标靶、迈步式锚支护装备等组成的相对位姿测量系统;通过红外热成像相机捕捉安装在掘支锚机器人联合机组上的热源标靶信号源,并对其输出的热成像图像进行畸变校正与图像增强处理;其次,采用UNet分割算法对热源标靶信号源进行区域分割,再利用图像二值化与形态学处理对分割后的信号源区域进行特征细化,并结合OpenCV库函数提取信号源中心点的像素坐标;再者,采用P4P方法求解4组信号源中心点的空间三维坐标,并通过坐标系转换解算掘支锚机器人联合机组的相对位姿参数;然后,以Realsense D435i深度相机结合奇异值分解算法测得的相对位姿参数作为真值,进一步计算所提方法的测量误差,以验证所提方法的可行性与有效性;最后,搭建了基于红外热成像的掘支锚机器人联合机组相对位姿检测实验平台,实验结果表明,在2.40~4.80 m测量范围内,在迈步式锚支护装备坐标系下,掘进机沿X、Y、Z三轴方向平移量相对误差绝对值均值分别为0.0216、0.0198、0.0269 m,绕X、Y、Z三轴的旋转角度相对误差绝对值均值分别为1.45°、1.07°、1.27°,可以满足煤矿复杂环境掘支锚机器人联合机组相对位姿感知需求。 展开更多
关键词 掘支锚机器人联合机组 红外热成像 视觉测量 UNet分割算法 位姿测量
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