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为了准确地从复杂干扰背景下检测出真实弱小目标,本文引入视觉显著性,设计了基于快速光谱尺度空间与动态管道滤波的红外目标检测算法。基于真实目标与背景内容之间的整体差异,引入快速光谱尺度空间与阈值分割技术,设计视觉显著性机制,对红外图像完成处理,输出全局显著性映射,以高效过滤干扰背景内容。考虑目标与背景的局部特征差异,构建自适应局部对比度增强机制,对粗检测结果实施处理,获取对应的局部显著性映射,改善视觉显著性区域内目标的对比度。引入高斯差分理论,通过估算每一帧红外图像中的目标像素直径,形成动态管道滤波,充分消除虚警,准确识别出弱小目标。多组实验数据显示:较已有的红外目标检测技术而言,在各种不同的复杂背景干扰下,所提算法呈现出更好的检测能力,拥有更理想的接收机工作特性R O C ![]()
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曲线。 相似文献
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Polarization imaging can retrieve inaccurate objects’ 3D shapes with fine textures, whereas coarse but accurate depths can be provided by binocular stereo vision. To take full advantage of these two complementary techniques, we investigate a novel 3D reconstruction method based on the fusion of polarization imaging and binocular stereo vision for high quality 3D reconstruction. We first generate the polarization surface by correcting the azimuth angle errors on the basis of registered binocular depth, to solve the azimuthal ambiguity in the polarization imaging. Then we propose a joint 3D reconstruction model for depth fusion, including a data fitting term and a robust low-rank matrix factorization constraint. The former is to transfer textures from the polarization surface to the fused depth by assuming their relationship linear, whereas the latter is to utilize the low-frequency part of binocular depth to improve the accuracy of the fused depth considering the influences of missing-entries and outliers. To solve the optimization problem in the proposed model, we adopt an efficient solution based on the alternating direction method of multipliers. Extensive experiments have been conducted to demonstrate the efficiency of the proposed method in comparison with state-of-the-art methods and to exhibit its wide application prospects in 3D reconstruction. 相似文献
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《Journal of dairy science》2022,105(3):2408-2425
Reggiana and Modenese are autochthonous cattle breeds, reared in the North of Italy, that can be mainly distinguished for their standard coat color (Reggiana is red, whereas Modenese is white with some pale gray shades). Almost all milk produced by these breeds is transformed into 2 mono-breed branded Parmigiano-Reggiano cheeses, from which farmers receive the economic incomes needed for the sustainable conservation of these animal genetic resources. After the setting up of their herd books in 1960s, these breeds experienced a strong reduction in the population size that was subsequently reverted starting in the 1990s (Reggiana) or more recently (Modenese) reaching at present a total of about 2,800 and 500 registered cows, respectively. Due to the small population size of these breeds, inbreeding is a very important cause of concern for their conservation programs. Inbreeding is traditionally estimated using pedigree data, which are summarized in an inbreeding coefficient calculated at the individual level (FPED). However, incompleteness of pedigree information and registration errors can affect the effectiveness of conservation strategies. High-throughput SNP genotyping platforms allow investigation of inbreeding using genome information that can overcome the limits of pedigree data. Several approaches have been proposed to estimate genomic inbreeding, with the use of runs of homozygosity (ROH) considered to be the more appropriate. In this study, several pedigree and genomic inbreeding parameters, calculated using the whole herd book populations or considering genotyping information (GeneSeek GGP Bovine 150K) from 1,684 Reggiana cattle and 323 Modenese cattle, were compared. Average inbreeding values per year were used to calculate effective population size. Reggiana breed had generally lower genomic inbreeding values than Modenese breed. The low correlation between pedigree-based and genomic-based parameters (ranging from 0.187 to 0.195 and 0.319 to 0.323 in the Reggiana and Modenese breeds, respectively) reflected the common problems of local populations in which pedigree records are not complete. The high proportion of short ROH over the total number of ROH indicates no major recent inbreeding events in both breeds. ROH islands spread over the genome of the 2 breeds (15 in Reggiana and 14 in Modenese) identified several signatures of selection. Some of these included genes affecting milk production traits, stature, body conformation traits (with a main ROH island in both breeds on BTA6 containing the ABCG2, NCAPG, and LCORL genes) and coat color (on BTA13 in Modenese containing the ASIP gene). In conclusion, this work provides an extensive comparative analysis of pedigree and genomic inbreeding parameters and relevant genomic information that will be useful in the conservation strategies of these 2 iconic local cattle breeds. 相似文献
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Aggregate question answering essentially returns answers for given questions by obtaining query graphs with unique dependencies between values and corresponding objects. Word order dependency, as the key to uniquely identify dependency of the query graph, reflects the dependencies between the words in the question. However, due to the semantic gap caused by the expression difference between questions encoded with word vectors and query graphs represented with logical formal elements, it is not trivial to match the correct query graph for the question. Most existing approaches design more expressive query graphs for complex questions and rank them just by directly calculating their similarities, ignoring the semantic gap between them. In this paper, we propose a novel Structure-sensitive Semantic Matching(SSM) approach that learns aligned representations of dependencies in questions and query graphs to eliminate their gap. First, we propose a cross-structure matching module to bridge the gap between two modalities(i.e., textual question and query graph). Then, we propose an entropy-based gated AQG filter to remove the structural noise caused by the uncertainty of dependencies. Finally, we present a two-channel query graph representation that fuses the semantics of abstract structure and grounding content of the query graph explicitly. Experimental results show that SSM could learn aligned representations of questions and query graphs to eliminate the gaps between their dependencies, and improves up to 12% (F1 score) on aggregation questions of two benchmark datasets. 相似文献
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Copy Move is a technique widespreadly used in digital image tampering, meaning Copy Move Forgery Detection (CMFD) is still a significant research. In this paper, a novel CMFD method is proposed, including double matching process and region localizing process. In double matching process, the first matching is conducted on Delaunay triangles consisting of Local Intensity Order Pattern (LIOP) keypoints, to find the approximate location of suspicious regions. In order to find sufficient keypoint pairs, the existing set of matching triangles is expanded by adding their neighbors iteratively, covering the whole tampered regions, and the second matching with a looser threshold is conducted on the vertices. In the region localizing process, considering the case of multiple copies, Density-Based Spatial Clustering of Applications with Noise (DBSCAN) is used to classify the keypoint pairs described in a new model. Experimental results indicate that the proposed method, with good robustness, outperforms some state-of-the-art methods. 相似文献
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国内某炼钢厂为保证浇注周期较短的2号连铸机连浇,多座转炉需同时向该连铸机供应钢水,导致炉 机对应关系不明确,生产组织难度较大。通过对该厂炼钢 连铸过程的工序作业周期与生产运行模式进行解析,在保证连铸机连浇的基础上,探究合理的炉 机对应关系,改善该厂的生产顺行。结果表明,在“一一对应”运行模式下,2号连铸机最大连浇炉数仅为6炉;而在“定炉对定机”运行模式下,若适时接受3号转炉冶炼的钢水,2号连铸机最大连浇炉数可延长至19炉。在此基础上,通过对连铸机“柔性”的优化和钢水供应的合理调配,2号连铸机可满足实际生产的连浇要求。此外,运用“炉→机”匹配度进行评价,计算结果表明优化后的炉 机对应关系得到显著改善。 相似文献
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粒子群算法因其形式比较简洁,参数设置灵活,操作简便易行,并且能够快速收敛,从而引起广泛关注。但是传统的粒子群算法也有缺陷:收敛速度慢以及容易陷入局部最优等。针对这些问题,本文借鉴小生境的方法,在进化初始阶段,对种群进行划分,将初始种群分为子种群,对不同的子种群进行不同的变异策略;在进化过程中,针对不同的子种群,设置不同的惯性权重因子ω,用来增强全局搜索能力与局部搜索能力。实验结果表明,本文提出的算法较传统的粒子群算法具有较快的收敛性以及找寻的全局最优解更接近真实解集,收敛精度比较高。 相似文献