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11.
自适应双边滤波红外弱小目标检测方法   总被引:1,自引:0,他引:1  
针对红外弱小目标检测,提出一种基于自适应双边滤波的背景预测算法.该算法利用空域低通滤波和图像灰度信息的非线性组合,自适应的对背景进行预测,达到提高弱小目标检测性能的目的.仿真和实验表明:与小波滤波的检测算法相比,该算法能够更加有效地从结构化背景中检测目标抑制背景.  相似文献   
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运用动力响应时程分析和应用理论,结合国内首次出现的对称土工格栅加筋土双边坡实体工程,建立三维有限元分析模型,研究对称土工格栅加筋土双边坡的动态特征。分析在地震加速度下的位移大小、变形情况、拐角处填土剪切应力、坡脚处土工格栅的拉力和结构加速度,以及最大变形、位移部位。通过数值模拟分析得到地震加速度为0.3509g下结构的各项响应值均未超过设计极限值,表明该结构在地震加速度下稳定好、抗震性能好。分析结果能为对称土工格栅加筋土双边坡的抗震设计提供一定的参考价值。  相似文献   
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The basic TDLMS (Two-Dimensional Least Mean Square) filter fails to detect infrared small targets consistently, especially under conditions of heavy noise and distinct cloud edges. This paper proposes a robust and efficient small-target detection method based on the basic TDLMS filter. The method first smooths the input image with a Gaussian filter of adaptive variance, and then employs TDLMS with a selected step size to filter the image with rightward and leftward iterations. Two prediction error images are obtained by subtracting the prediction images of the bilateral filtering from the original input image. Each prediction error image is separated into positive and negative prediction error images. That is, four images are generated in the bilateral filtering. The final image is obtained by fusing these four images. Experimental results show that the proposed method achieves significant improvement in background suppression and detection performance over the basic TDLMS filter and other improved TDLMS filters.  相似文献   
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Hard or abrupt glottal attack (HGA) is one of the vocal behaviors often associated with benign lesion of the vocal folds. This study was designed to determine whether the frequency of HGA was different in hyperfunctional voice patients with and without vocal fold masses. One hundred and forty-seven subjects were studied. All subjects received a complete otolaryngological evaluation including strobovideolaryngoscopy, objective voice measures, and evaluation by a speech-language pathologist. Thirty-two patients were diagnosed with muscle tension dysphonia (19 male, 13 female) without vocal fold masses. Fifty-seven patients were diagnosed with unilateral vocal fold masses (29 male, 28 female), most of which were cysts. Fifty-eight patients were diagnosed with bilateral vocal fold masses (13 male, 45 female). Of the 45 females with bilateral vocal fold masses. 26 had a vocal cyst and reactive nodule and 19 had bilateral vocal fold nodules. The control group was balanced and matched based on sex and on percentage of singers and nonsingers. It consisted of 49 subjects with no vocal fold pathology (20 male, 29 female). The group was composed of professional speakers, singers, and nonprofessional speakers. All voice disordered groups demonstrated higher frequencies of HGA than the control group. Differences were found between the male and female subjects in this study. No differences were found between the various disorders. Differences were also found between the subgroups of bilateral masses, where the bilateral nodules group presented a higher frequency of HGA than the cyst and contralateral reactive nodule.  相似文献   
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唐卡图像的抽象化是用非真实感技术表现唐卡的一种形式。根据唐卡图像线条和色彩的特点,提出一种抽象化绘制方法。首先,根据唐卡RGB颜色空间的梯度提出粗略的轮廓,以此为输入对其进行边缘切向流构造,在此基础上进行基于高斯差分滤波提取平滑的唐卡线条画;与此同时,对唐卡图像进行双边滤波、剔除干扰信息并模糊化图像;然后将线条画和模糊的图像进行融合。针对不同的唐卡图像进行实验,结果显示该方法能对唐卡图像进行有效、高质量的抽象化处理。  相似文献   
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Inspired by a recent result that a weakly hypercyclic operator may fail to be norm hypercyclic, we show there exists a weakly supercyclic operator that fails to be norm supercyclic. Moreover, despite a classical result of Hilden and Wallen that every unilateral weighted backward shift is supercyclic, we show such an operator may have a weakly supercyclic vector that is not a norm supercyclic vector. In addition to these results, we extend a result of Kitai by showing a hyponormal operator cannot be weakly hypercyclic.  相似文献   
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Exchange of risks is considered here as a transferable-utility, cooperative game, featuring risk averse players. Like in competitive equilibrium, a core solution is determined by shadow prices on state-dependent claims. And like in finance, no risk can properly be priced merely in terms of its marginal distribution. Pricing rather depends on the pooled risk and on the convolution of individual preferences. The paper elaborates on these features, placing emphasis on the role of prices and incompleteness. Some novelties come by bringing questions about existence, computation and uniqueness of solutions to revolve around standard Lagrangian duality. Especially outlined is how repeated bilateral trade may bring about a price-supported core allocation.  相似文献   
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