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91.
交通标志识别对于自动驾驶和辅助驾驶系统中非常重要,但大多数相关研究仅局限在白天场景的识别,若用于夜间,光强差异太大会导致识别准确率显著下降。为解决该问题,文中提出了光强分类模型,可根据光强强度划分场景识别标志牌,保证夜间较高的识别率。该模型通过KNN和SVM构造邻接矩阵和训练特征向量来判断分场景处理出的ROI,从而确定具体标志牌种类。实验证明,该模型在不同环境下识别准确率高达98.1%。  相似文献   
92.
叶子  李若凡 《电子科技》2019,32(6):54-57
随着通信技术以及移动终端的发展,Android系统由于其本身的开源性,滋生了大量的恶意代码。为了满足Android手机用户的安全需求,文中基于Android,采用SVM机器学习思想,构建了恶意代码检测模型,并开发了一套手机恶意代码检测与防护系统,可以对其进行快速检测和深度检测。系统经Android手机测试结果表明,其具有较好的检测精度以及较低的恶意代码漏报率。  相似文献   
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94.
In this paper, we propose a novel approach for key frames extraction on human action recognition from 3D video sequences. To represent human actions, an Energy Feature (EF), combining kinetic energy and potential energy, is extracted from 3D video sequences. A Self-adaptive Weighted Affinity Propagation (SWAP) algorithm is then proposed to extract the key frames. Finally, we employ SVM to recognize human actions on the EFs of selected key frames. The experiments show the information including whole action course can be effectively extracted by our method, and we obtain good recognition performance without losing classification accuracy. Moreover, the recognition speed is greatly improved.  相似文献   
95.
This paper presents a novel computer aided technique for measurement of melanoma depth of invasion. Melanoma is the deadliest form of skin cancer with worldwide increasing incidences. For a conclusive diagnosis of melanoma, skin biopsies should be examined under a microscope. Visual inspection of microscopic samples is often subjective, time-consuming, cumbersome and prone to human errors. This fact demonstrates the necessity of developing an automated method which assists pathologists in evaluating histopathological samples more accurately in the busy clinical environment. To the best of our knowledge, this is the first time that a computer-assisted diagnosis algorithm has been applied in measurement of melanoma invasion depth. The proposed method uses a clustering algorithm for granular layer extraction and a pre-trained SVM classifier for detection of malignant melanocytes. The experimental results with average error of 3.9 μm demonstrate that the proposed method is reliable and effective.  相似文献   
96.
In sport sceneries, automatically recognizing human actions is a useful technique that can be popularly applied in may domains, such as human body tracking and athlete behavior analysis Most state-of-the-art deep architectures have achieved competitive performance in recognizing human action. However, it is still a challenging task due to the unavoidable occlusion, camera angle changes, and varied human posture. In this paper, we propose a novel deep multimodal feature fusion algorithm for human action recognition. The key technique is a multi-model feature fusion scheme. More specifically, we fuse visual feature, skeleton posture, probability maps and audio signal into a hybrid feature, which is utilized to represent human action. Then these feature channels are optimally combined using a deep model, wherein the weights of multiple feature channels can be predicted intelligently. Finally, the optimally fused feature are fed into a multi-class SVM for conducting human action recognition. Extensive comparative results and parameter analysis have shown the effectiveness of our proposed method.  相似文献   
97.
《Electrophoresis》2018,39(7):948-956
Microwell arrays are widely used for the analysis of fluorescent‐labelled biomaterials. For rapid detection and automated analysis of microwell arrays, the computational image analysis is required. Support Vector Machines (SVM) can be used for this task. Here, we present a SVM‐based approach for the analysis of microwell arrays consisting of three distinct steps: labeling, training for feature selection, and classification into three classes. The three classes are filled, partially filled, and unfilled microwells. Next, the partially filled wells are analyzed by SVM and their tendency towards filled or unfilled tested through applying a Gaussian filter. Through this, all microwells can be categorized as either filled or unfilled by our algorithm. Therefore, this SVM‐based computational image analysis allows for an accurate and simple classification of microwell arrays.  相似文献   
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99.
李灿标  郑楚君 《激光杂志》2020,41(1):185-191
视网膜血管自动分割能辅助诊断某些眼底疾病和系统性血管疾病。为了提高血管自动分割的效率,因此提出了一种线算子引导Gabor小波的视网膜血管分割方法。利用线算子检测血管方向的最优匹配角,将其作为Gabor小波变换的旋转角构建4个不同尺度的Gabor小波,并提取4维Gabor小波特征,加上两个线强度和预处理后的图像灰度,构建7维特征向量,采用SVM进行分类。与其他基于Gabor小波的方法相比,本方法只需计算最优匹配角所对应方向的Gabor小波特征,大大降低了多尺度Gabor小波特征提取的计算量,此外线算子特征与Gabor小波特征的良好互补性,有利于提高血管与背景的辨别度。在DRIVE眼底数据库上进行实验,其平均准确率、灵敏度及特异性分别为0.9361、0.8238及0.9554,获得了不错的分割性能。  相似文献   
100.
汪威  李浩然  张开颜  李阳  吴兵硕 《半导体技术》2019,44(3):210-215,222
提出一种基于机器视觉的陶瓷方形扁平封装外观缺陷检测方法。对于封装外形尺寸较大而缺陷较细微的情形,将待检片分为多个区域与标准样片进行比对检测。首先通过Foerstner特征点检测法提取标准片图像的特征点,然后使用随机抽样一致性(RANSAC)图像匹配算法,将所有标准片图像拼接并融合生成一张标准片全幅面模板,再将待检片分区与标准片模板进行序贯比对,以提取可疑区域,最后利用支持向量机(SVM)分类器对可疑区域进行筛选分类。实验结果表明,这种方法不仅克服了传统视觉检测过程中视野范围与图像分辨率相互制约的矛盾,且对陶瓷方形扁平封装表面缺陷具有较高的检出率。  相似文献   
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