共查询到19条相似文献,搜索用时 78 毫秒
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本文提出了一种基于最小一乘背景预测的红外小目标检测算法.首先在建立最小一乘准则背景预测模型的基础上,根据最小一乘估计的性质,应用线性规划的方法解决最小一乘估计中极值的选取问题;然后将原始图像与预测图像相减得到预测残差图像;最后利用基于二维指数熵的图像阚值选取快速算法进行分割.文中给出了实验结果与分析,并与基于最小二乘背景预测的检测算法作了比较.实验结果表明,本文提出的算法具有更高的检测概率,优于基于最小二乘背景预测的检测算法. 相似文献
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无人机产业近年来发展迅猛,在军用和民用方面都拥有广泛的应用前景。无人机的航迹记录在其航行过程中发挥着重要作用,无人机的航迹预测也成为当前世界研究的热点,使用神经网络进行航迹预测更可以充分发挥其优势。首先对国内外学者关于航迹预测的文献进行了梳理,根据航迹预测的原理对目前飞行器航迹预测算法进行了总结和分类,针对利用神经网络模型预测无人机航迹并逐步改进模型以提高预测精度的问题进行了研究。接着对于传统神经网络模型预测精度不够高的问题,提出一种带误差修正的嵌套长短期记忆 (ENLSTM) 神经网络预测模型。ENLSTM 在嵌套长短期记忆网络模型的基础上引入了误差修正项,从而使得预测精度更高。最后使用 BP、RNN、LSTM 和 ENLSTM 四种神经网络模型分别对无人机的真实航迹数据和模拟航迹数据进行仿真实验,得出结论:循环神经网络相对 BP 神经网络在无人机航迹的预测上更具有优势,基于基础循环神经网络的逐步改进提升了模型的预测能力,ENLSTM 模型对于无人机的航迹预测具有更好的效果。 相似文献
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目的为了改进当前布匹检测算法覆盖瑕疵种类不全、瑕疵检测准确率低和定位精度差的问题,提出一种端到端的素色布匹瑕疵检测的实用算法。方法首先通过图像增强扩充样本数量,使用以Resnet50为主干的Cascade-RCNN网络,通过加入可变形卷积、特征融合网络,增加锚框数目的方法实现素色布匹瑕疵检测。结果通过实验对比表明,该算法可实现检测20种布匹瑕疵,检测是否为瑕疵布匹的准确率为97%,瑕疵定位的平均检测精度为65%,每张样本平均时间为80 ms。结论该算法有效提升了布匹瑕疵检测的准确率和精度,检测瑕疵类别更全面,并且可以获取缺陷位置和类别,能够满足工业上的生产需求。 相似文献
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Machine Learning (ML) algorithms have been widely used for financial time series prediction and trading through bots. In this work, we propose a Predictive Error Compensated Wavelet Neural Network (PEC-WNN) ML model that improves the prediction of next day closing prices. In the proposed model we use multiple neural networks where the first one uses the closing stock prices from multiple-scale time-domain inputs. An additional network is used for error estimation to compensate and reduce the prediction error of the main network instead of using recurrence. The performance of the proposed model is evaluated using six different stock data samples in the New York stock exchange. The results have demonstrated significant improvement in forecasting accuracy in all cases when the second network is used in accordance with the first one by adding the outputs. The RMSE error is 33% improved when the proposed PEC-WNN model is used compared to the Long Short-Term Memory (LSTM) model. Furthermore, through the analysis of training mechanisms, we found that using the updated training the performance of the proposed model is improved. The contribution of this study is the applicability of simultaneously different time frames as inputs. Cascading the predictive error compensation not only reduces the error rate but also helps in avoiding overfitting problems. 相似文献
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混合色彩空间多信息融合的运动目标检测算法 总被引:1,自引:0,他引:1
针对传统帧间差分算法存在漏检、空洞和虚假目标等问题,提出一种改进的帧间差分算法。对几种常见色彩空间的运动目标检测效果进行实验对比分析,选取检测效果优良的色彩通道分量构建运动目标检测的混合色彩空间CbVb*。为充分利用帧间信息的相关性,根据CbVb*空间的场景像素变化特性,提出七帧帧间差分算法以获取运动目标的时域帧间差分;采用自适应阈值的Canny算子得到梯度域的运动目标边缘,将时域帧间差分与梯度域目标边缘进行融合,并对融合信息进行腐蚀和膨胀处理得到最终的检测结果。实验结果表明,改进的算法可以更准确地检测出运动目标,并具有较好的鲁棒性、适应性和实时性。 相似文献
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PM2.5 has a non-negligible impact on visibility and air quality as an important component of haze and can affect cloud formation and rainfall and thus change the climate, and it is an evaluation indicator of air pollution level. Achieving PM2.5 concentration prediction based on relevant historical data mining can effectively improve air pollution forecasting ability and guide air pollution prevention and control. The past methods neglected the impact caused by PM2.5 flow between cities when analyzing the impact of inter-city PM2.5 concentrations, making it difficult to further improve the prediction accuracy. However, factors including geographical information such as altitude and distance and meteorological information such as wind speed and wind direction affect the flow of PM2.5 between cities, leading to the change of PM2.5 concentration in cities. So a PM2.5 directed flow graph is constructed in this paper. Geographic and meteorological data is introduced into the graph structure to simulate the spatial PM2.5 flow transmission relationship between cities. The introduction of meteorological factors like wind direction depicts the unequal flow relationship of PM2.5 between cities. Based on this, a PM2.5 concentration prediction method integrating spatial-temporal factors is proposed in this paper. A spatial feature extraction method based on weight aggregation graph attention network (WGAT) is proposed to extract the spatial correlation features of PM2.5 in the flow graph, and a multi-step PM2.5 prediction method based on attention gate control loop unit (AGRU) is proposed. The PM2.5 concentration prediction model WGAT-AGRU with fused spatiotemporal features is constructed by combining the two methods to achieve multi-step PM2.5 concentration prediction. Finally, accuracy and validity experiments are conducted on the KnowAir dataset, and the results show that the WGAT-AGRU model proposed in the paper has good performance in terms of prediction accuracy and validates the effectiveness of the model. 相似文献
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对于背景呈非线性变化的复杂图像,用背景预测的方法对红外点目标进行检测时,传统的线性最小二乘法(Least Squares,LS)的效果比较差.文章使用核方法(Kernel Methods,KMs)推导了最小二乘法的非线性版本:核最小二乘算法(Kernel Least Squares,KLS);进一步推导出了更适合动态系统时序预测的指数加权形式的核最小二乘算法(Kemel Exponential wleighted Least Squares,KEWLS).提出了一种基于核方法的红外点目标检测算法,先用KEWLS非线性回归算法预测红外图像背景,再通过自适应门限检测残差图像中的目标,非线性函数回归和红外序列图像检测实验表明核方法较大地改进了算法的非线性函数估计与红外背景预测能力. 相似文献
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零件面形精度满足要求是超精密装备实现其关键功能的重要保证.影响工件加工面形精度的因素很多,机床体误差是其中最关键的因素.通过构建机床误差元与加工面形误差之间的直接关系来进行面形误差预测研究.提出了一种基于机床体误差模型的频域多尺度面形误差预测方法,该方法可结合机床体误差模型、工艺参数、加工轨迹等进行频域多尺度面形误差预测,可为加工路径规划、机床设计等提供理论参考,从而提高加工精度.进行了低频PV面形误差预测的实例研究,采用的机床为一台五轴联动超精密机床,加工表面为凹形截圆锥台锥面.通过实验与理论分别获得PV面形误差,其相对误差为17.3%,证明基于机床体误差模型的低频PV面形误差预测是可行的. 相似文献