共查询到19条相似文献,搜索用时 31 毫秒
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分析了动力装置运行状态特点和预测要求,依据分形和支持向量回归理论,建立了基于分形与支持向量回归的状态趋势预测模型。其中,以振动烈度作为描述机组状态的特征数据来构建时间序列,对其进行相空间重构,根据最小嵌入维数来确定支持向量机输入节点数,采用支持向量回归算法对机组状态趋势进行预测。应用案例研究和实验对比分析的结果表明,研究的状态预测模型单步预测的平均相对误差为1.7881%, 30步预测的平均相对误差为3.3983%,预测模型能较好地满足动力装置状态趋势预测要求。 相似文献
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针对神经网络方法在切削力预测方面存在的缺陷,提出了一种新的基于支持向量回归机的切削力智能预测方法。分析了以往切削力预测模型中输入参数和输出参数的选择问题,在此基础上选择轴向切深、进给量、主轴转速和曲面半径四个关键指标作为预测模型的输入,选择XY平面上的切削力合力和轴向切削力作为预测模型的输出,进一步建立了基于支持向量回归机的切削力预测模型。仿真实例的预测结果表明,建立的智能切削力预测模型合理有效。 相似文献
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采用支持向量机回归算法对切削参数进行预测,并与试验数据进行比较,计算结果证明了该算法在切削参数预测中的有效性和实用性。 相似文献
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根据材料疲劳损伤的特点,提出了基于支持向量机回归算法的材料疲劳寿命预测方法。收集材料疲劳性能数据构建训练样本集,建立基于支持向量机回归算法的疲劳寿命预测模型,对疲劳载荷预处理后就可以计算出疲劳寿命。预测结果表明,该方法可利用较少的材料疲劳性能数据,实现疲劳寿命的预测。 相似文献
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Data-driven prognostics based on sensor or historical test data have become appropriate prediction means in prognostics and health management (PHM) application. However, most traditional data-driven prognostics methods are off-line which would be seriously limited in many PHM systems needed on-line predicting or real-time processing. Furthermore, even in some on-line prediction algorithms such as Online Support Vector Regression (Online SVR) and Incremental learning algorithm, there are conflicts and trade-offs between prediction efficiency and accuracy. Therefore, in different PHM applications, prognostics algorithms should be on-line, flexible and adaptive to balance the prediction efficiency and accuracy. An on-line adaptive data-driven prognostics strategy is proposed with five various optimized on-line prediction algorithms based on Online SVR. These five algorithms are improved with kernel combination and sample reduction to realize higher precision and efficiency. These algorithms can achieve more accurate results by data pre-processing and model optimization, moreover, faster operating speed and lower computational complexity can be obtained by optimization of training process with on-line data reduction. With these different improved Online SVR methods, varies of prediction with different precision and efficiency demands could be fulfilled by an adaptive strategy. To evaluate the proposed prognostics strategy, we have executed simulation experiments with Tennessee Eastman (TE) process. In addition, the prediction strategies are also applied and evaluated by traffic mobile communication data from China Mobile Communications Corporation Heilongjiang Co., Ltd. Experiments and test results prove its effectiveness and confirm that the algorithms can be effectively applied to the on-line status prediction with increased performance in both precision and efficiency. 相似文献
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针对室内无线局域网环境中无线信号不稳定,以及传统支持向量回归定位算法在构建位置坐标与信号强度时的单输出导致位置坐标信息之间的关联性降低的问题,提出一种基于改进支持向量回归的室内定位方法。该算法首先对采集到的接收信号强度(RSS)指纹进行对数处理使其更符合正态分布,然后采用高斯滤波过滤掉小概率的指纹值之后构建指纹数据库;其次,为了降低单独构建x与y坐标模型的误差,提高二维位置信息与RSS之间的关联性,在训练阶段增加训练一个校正坐标z=x·y;最后,根据加权反K近邻的方法得到最优的位置坐标。实验结果表明,提出的算法可以减少室内复杂环境带来的噪声干扰,与传统的支持向量回归定位算法相比有更高的定位精度。 相似文献
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Linearization error of the simplified linear electrical capacitance tomography (ECT) model is one of the leading causes of ECT reconstruction errors. In this paper, the least squares support vector regression (LSSVR) is used to fit the correlation between the capacitance vector and the linearization error. And it is trained by the training samples of typical phase distributions. When removing the linearization error from equations derived by the linear model, the reconstruction problem becomes an exact linear inverse problem because the nonlinearity of ECT is completely included in the linearization error. Then a reconstruction algorithm combining the LSSVR and the Landweber iteration is proposed. Numerical results show that the proposed algorithm achieves significantly better reconstruction accuracies than the linear back projection and the Landweber algorithm for both the noise-free and noisy cases. Compared with the Landweber algorithm, The image errors of the reconstructions are reduced by about 23%–68%, and the correlation coefficient increased by about 0.04–0.14. And the calculation time of the proposed algorithm for all the tested cases is about 0.4–0.6s, which makes it have the potential for real-time imaging. Static experimental results show that the reconstructions of the proposed algorithm have more accurate phase boundary shapes and fewer artifacts. 相似文献
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Yongbin Lee Sangyup Oh Dong-Hoon Choi 《Journal of Mechanical Science and Technology》2008,22(2):213-220
Polynomial regression (PR) and kriging are standard meta-model techniques used for approximate optimization (AO). Support
vector regression (SVR) is a new meta-model technique with higher accuracy and a lower standard deviation than existing techniques.
In this paper, we propose a sequential approximate optimization (SAO) method using SVR. Inherited latin hypercube design (ILHD)
is used as the design of experiment (DOE), and the trust region algorithm is used as the model management technique, both
adopted to increase efficiency in problem solving. We demonstrate the superior accuracy and efficiency of the proposed method
by solving three mathematical problems and two engineering design problems. We also compare the proposed method with other
meta-models such as kriging, radial basis function (RBF), and polynomial regression. 相似文献
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用支持向量回归法实现单帧图像超分辨率重建 总被引:1,自引:0,他引:1
由于一些传统的超分辨率重建算法学习多幅不同类别的图像仍无法获得好的重建效果,本文提出了一种基于支持向量回归机和光栅扫描的单帧图像超分辨率重建算法。该算法首先采用光栅扫描法对一组高低分辨率训练图像提取图像块,从块中分别抽取输入向量和标签像素。利用Log算子判断这些块是属于高频空间还是低频空间,从而构建高低频空间向量对并对其进行优化。然后,用支持向量回归机(SVR)工具训练优化后的向量对,得到高低频空间下的两个字典;抽取测试低分辨率图像中的块并得到高低频空间下的输入向量,利用SVR工具回归对应的属于超分辨率图像块的标签像素并得到回归后的图像。最后,对图像进行后处理得到最终的超分辨率图像。与其它算法的对比实验表明:提出的算法具有较好的视觉效果。特别在放大倍数为2时,提出的算法在不同图像上的峰值信噪比(PSNR)和结构相似度(SSIM)值较双三次插值法分别提高了3.1%~5.3%和1.5%~8.1%。得到的结果显示提出的算法获得了更好的重建效果。 相似文献
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Amit Kumar Gupta Sharath Chandra Guntuku Raghuram Karthik Desu Aditya Balu 《The International Journal of Advanced Manufacturing Technology》2015,78(1-4):331-339
This paper focuses on optimisation of process parameters of the turning operation, using artificial intelligence techniques such as support vector regression (SVR) and artificial neural networks (ANN) integrated with genetic algorithm (GA). The model is trained using the turning parameters as the input and corresponding surface roughness, tool wear and power required as the output. Data, obtained from conducting experiments is analysed using support vector machine (SVM) and artificial neural network. SVM, a nonlinear model, is learned by linear learning machine by mapping into high-dimensional kernel-induced feature space. The genetic algorithm is integrated with these to find the optimum from the response surface generated. The results are compared with those obtained by integrating GA with traditional models like response surface methodology (RSM) and regression analysis (RA). This paper illustrates the impact that techniques based on artificial intelligence have on optimising processes. 相似文献
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针对WLAN室内定位系统中存在的接收信号强度指示(RSSI)时变特性降低定位精度的问题,提出一种基于主成分分析(PCA)和最小二乘支持向量回归机(LS-SVR)的PCA-LSSVR定位算法。该算法首先利用PCA对采集的各接入点(AP)的原始RSSI信号进行数据降维和去相关处理,提取主要的定位特征数据;然后利用LS-SVR构建指纹点的定位特征数据与其位置的非线性关系,并利用此关系对测试点的位置进行回归预测。实验结果表明,该算法的定位精度优于几种传统的定位算法,是一种性能良好的WLAN室内定位算法。 相似文献
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