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Composition Analysis and Identification of Ancient Glass Products Based on L1 Regularization Logistic Regression
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作者 Yuqiao Zhou Xinyang Xu Wenjing Ma 《Applied Mathematics》 2024年第1期51-64,共14页
In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluste... In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluster analysis, hyper-parameter test and other models, and SPSS, Python and other tools were used to obtain the classification rules of glass products under different fluxes, sub classification under different chemical compositions, hyper-parameter K value test and rationality analysis. Research can provide theoretical support for the protection and restoration of ancient glass relics. 展开更多
关键词 Glass Composition L1 regularization Logistic Regression model K-Means Clustering Analysis Elbow Rule Parameter Verification
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Subspace Minimization Conjugate Gradient Method Based on Cubic Regularization Model for Unconstrained Optimization 被引量:1
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作者 Ting Zhao Hongwei Liu 《Journal of Harbin Institute of Technology(New Series)》 CAS 2021年第5期61-69,共9页
Many methods have been put forward to solve unconstrained optimization problems,among which conjugate gradient method(CG)is very important.With the increasing emergence of large⁃scale problems,the subspace technology ... Many methods have been put forward to solve unconstrained optimization problems,among which conjugate gradient method(CG)is very important.With the increasing emergence of large⁃scale problems,the subspace technology has become particularly important and widely used in the field of optimization.In this study,a new CG method was put forward,which combined subspace technology and a cubic regularization model.Besides,a special scaled norm in a cubic regularization model was analyzed.Under certain conditions,some significant characteristics of the search direction were given and the convergence of the algorithm was built.Numerical comparisons show that for the 145 test functions under the CUTEr library,the proposed method is better than two classical CG methods and two new subspaces conjugate gradient methods. 展开更多
关键词 cubic regularization model conjugate gradient method subspace technique unconstrained optimization
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Some Properties of a Recursive Procedure for High Dimensional Parameter Estimation in Linear Model with Regularization
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作者 Hong Son Hoang Remy Baraille 《Open Journal of Statistics》 2014年第11期921-932,共12页
Theoretical results related to properties of a regularized recursive algorithm for estimation of a high dimensional vector of parameters are presented and proved. The recursive character of the procedure is proposed t... Theoretical results related to properties of a regularized recursive algorithm for estimation of a high dimensional vector of parameters are presented and proved. The recursive character of the procedure is proposed to overcome the difficulties with high dimension of the observation vector in computation of a statistical regularized estimator. As to deal with high dimension of the vector of unknown parameters, the regularization is introduced by specifying a priori non-negative covariance structure for the vector of estimated parameters. Numerical example with Monte-Carlo simulation for a low-dimensional system as well as the state/parameter estimation in a very high dimensional oceanic model is presented to demonstrate the efficiency of the proposed approach. 展开更多
关键词 Linear model regularization RECURSIVE Algorithm Non-Negative COVARIANCE Structure EIGENVALUE Decomposition
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A GAUSSIAN MIXTURE MODEL-BASED REGULARIZATION METHOD IN ADAPTIVE IMAGE RESTORATION
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作者 Liu Peng Zhang Yan Mao Zhigang 《Journal of Electronics(China)》 2007年第1期83-89,共7页
A GMM (Gaussian Mixture Model) based adaptive image restoration is proposed in this paper. The feature vectors of pixels are selected and extracted. Pixels are clustered into smooth,edge or detail texture region accor... A GMM (Gaussian Mixture Model) based adaptive image restoration is proposed in this paper. The feature vectors of pixels are selected and extracted. Pixels are clustered into smooth,edge or detail texture region according to variance-sum criteria function of the feature vectors. Then pa-rameters of GMM are calculated by using the statistical information of these feature vectors. GMM predicts the regularization parameter for each pixel adaptively. Hopfield Neural Network (Hopfield-NN) is used to optimize the objective function of image restoration,and network weight value matrix is updated by the output of GMM. Since GMM is used,the regularization parameters share properties of different kind of regions. In addition,the regularization parameters are different from pixel to pixel. GMM-based regularization method is consistent with human visual system,and it has strong gener-alization capability. Comparing with non-adaptive and some adaptive image restoration algorithms,experimental results show that the proposed algorithm obtains more preferable restored images. 展开更多
关键词 Image processing Gaussian Mixture model (GMM) Hopfield Neural Network (Hopfield-NN) regularization Adaptive image restoration
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Three-dimensional magnetotelluric regularized inversion based on smoothness-constrained model
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作者 童孝忠 柳建新 +2 位作者 郭荣文 刘海飞 龚露 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期509-513,共5页
How to get the rapid and stable inversion results and reconstruct the clear subsurface resistivity structures is a focus problem in current magnetotelluric inversion. A stable solution of an ill-posed inverse problem ... How to get the rapid and stable inversion results and reconstruct the clear subsurface resistivity structures is a focus problem in current magnetotelluric inversion. A stable solution of an ill-posed inverse problem was obtained by the regularization methods in which some desired structures were imposed to stabilize the inverse problem. By the smoothness-constrained model and approximate sensitivity method, the stable subsurface resistivity structures were reconstructed. The synthetic examples show that the smoothness-constrained regularized inversion method is effective and can be reasonable to reconstruct three-dimensional subsurface resistivity structures. 展开更多
关键词 MAGNETOTELLURIC regularized inversion approximate sensitivity smoothness-constrained model
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Iterative regularization method for image denoising with adaptive scale parameter
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作者 李文书 骆建华 +2 位作者 刘且根 何芳芳 魏秀金 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期453-456,共4页
In order to decrease the sensitivity of the constant scale parameter, adaptively optimize the scale parameter in the iteration regularization model (IRM) and attain a desirable level of applicability for image denoi... In order to decrease the sensitivity of the constant scale parameter, adaptively optimize the scale parameter in the iteration regularization model (IRM) and attain a desirable level of applicability for image denoising, a novel IRM with the adaptive scale parameter is proposed. First, the classic regularization item is modified and the equation of the adaptive scale parameter is deduced. Then, the initial value of the varying scale parameter is obtained by the trend of the number of iterations and the scale parameter sequence vectors. Finally, the novel iterative regularization method is used for image denoising. Numerical experiments show that compared with the IRM with the constant scale parameter, the proposed method with the varying scale parameter can not only reduce the number of iterations when the scale parameter becomes smaller, but also efficiently remove noise when the scale parameter becomes bigger and well preserve the details of images. 展开更多
关键词 iterative regularization model (IRM) total variation varying scale parameter image denoising
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Application of Bayesian regularized BP neural network model for analysis of aquatic ecological data—A case study of chlorophyll-a prediction in Nanzui water area of Dongting Lake 被引量:5
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作者 XU Min ZENG Guang-ming +3 位作者 XU Xin-yi HUANG Guo-he SUN Wei JIANG Xiao-yun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第6期946-952,共7页
Bayesian regularized BP neural network(BRBPNN) technique was applied in the chlorophyll-α prediction of Nanzui water area in Dongting Lake. Through BP network interpolation method, the input and output samples of t... Bayesian regularized BP neural network(BRBPNN) technique was applied in the chlorophyll-α prediction of Nanzui water area in Dongting Lake. Through BP network interpolation method, the input and output samples of the network were obtained. After the selection of input variables using stepwise/multiple linear regression method in SPSS i1.0 software, the BRBPNN model was established between chlorophyll-α and environmental parameters, biological parameters. The achieved optimal network structure was 3-11-1 with the correlation coefficients and the mean square errors for the training set and the test set as 0.999 and 0.000?8426, 0.981 and 0.0216 respectively. The sum of square weights between each input neuron and the hidden layer of optimal BRBPNN models of different structures indicated that the effect of individual input parameter on chlorophyll- α declined in the order of alga amount 〉 secchi disc depth(SD) 〉 electrical conductivity (EC). Additionally, it also demonstrated that the contributions of these three factors were the maximal for the change of chlorophyll-α concentration, total phosphorus(TP) and total nitrogen(TN) were the minimal. All the results showed that BRBPNN model was capable of automated regularization parameter selection and thus it may ensure the excellent generation ability and robustness. Thus, this study laid the foundation for the application of BRBPNN model in the analysis of aquatic ecological data(chlorophyll-α prediction) and the explanation about the effective eutrophication treatment measures for Nanzui water area in Dongting Lake. 展开更多
关键词 Dongting Lake CHLOROPHYLL-A Bayesian regularized BP neural network model sum of square weights
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Calculation of Activity Coefficient from Immiscible Binary Alloy Phase Diagram by Means of Modified Sub-regular Solution Model 被引量:3
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作者 张兆春 吴铸 +2 位作者 曾文明 陈念贻 彭瑞伍 《Rare Metals》 SCIE EI CAS CSCD 1998年第3期34-38,共5页
The modified sub regular solution model was used for a calculation of the activity coefficient of immiscible binary alloy systems. The parameters needed for the calculation are the interaction parameters, λ 1 a... The modified sub regular solution model was used for a calculation of the activity coefficient of immiscible binary alloy systems. The parameters needed for the calculation are the interaction parameters, λ 1 and λ 2, which are represented as a linear function of temperature, T . The molar excess Gibbs free energy, G m E, can be written in the form G m E= x A x B[( λ 11 + λ 12 T )+( λ 21 + λ 22 T ) x B ] The calculation is carried out numerically for three immiscible binary alloy systems, Al Pb, Cu Tl and In V. The agreement between the calculated and experimentally determined values of activity coefficient is excellent. 展开更多
关键词 Modified sub regular solution model Activity coefficient Immiscible binary alloy system
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Image Denoising Combining the P-M Model and the LLT Model 被引量:1
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作者 Qian Yang 《Journal of Computer and Communications》 2015年第10期22-30,共9页
In this paper, we present a noise removal technique by combining the P-M model with the LLT model. The combined technique takes full use of the advantage of both filters which is able to preserve edges and simultaneou... In this paper, we present a noise removal technique by combining the P-M model with the LLT model. The combined technique takes full use of the advantage of both filters which is able to preserve edges and simultaneously overcomes the staircase effect. We use a weighting function in our model, and compare this model with the P-M model as well as other fourth-order functional both in theory and numerical experiment. 展开更多
关键词 p-m model LLT model FOURTH-ORDER PDES COMBINATION Image DENOISING
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Regularization by Intrinsic Plasticity and Its Synergies with Recurrence for Random Projection Methods 被引量:1
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作者 Klaus Neumann Christian Emmerich Jochen J. Steil 《Journal of Intelligent Learning Systems and Applications》 2012年第3期230-246,共17页
Neural networks based on high-dimensional random feature generation have become popular under the notions extreme learning machine (ELM) and reservoir computing (RC). We provide an in-depth analysis of such networks w... Neural networks based on high-dimensional random feature generation have become popular under the notions extreme learning machine (ELM) and reservoir computing (RC). We provide an in-depth analysis of such networks with respect to feature selection, model complexity, and regularization. Starting from an ELM, we show how recurrent connections increase the effective complexity leading to reservoir networks. On the contrary, intrinsic plasticity (IP), a biologically inspired, unsupervised learning rule, acts as a task-specific feature regularizer, which tunes the effective model complexity. Combing both mechanisms in the framework of static reservoir computing, we achieve an excellent balance of feature complexity and regularization, which provides an impressive robustness to other model selection parameters like network size, initialization ranges, or the regularization parameter of the output learning. We demonstrate the advantages on several synthetic data as well as on benchmark tasks from the UCI repository providing practical insights how to use high-dimensional random networks for data processing. 展开更多
关键词 Extreme Learning Machine Reservoir Computing model SELECTION Feature SELECTION model Complexity INTRINSIC PLASTICITY regularization
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A Gradient Regularization Method in Crosswell Seismic Tomography
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作者 Wang Shoudong 《Petroleum Science》 SCIE CAS CSCD 2006年第3期36-40,共5页
Crosswell seismic tomography can be used to study the lateral variation of reservoirs, reservoir properties and the dynamic movement of fluids. In view of the instability of crosswell seismic tomography, the gradient ... Crosswell seismic tomography can be used to study the lateral variation of reservoirs, reservoir properties and the dynamic movement of fluids. In view of the instability of crosswell seismic tomography, the gradient method was improved by introducing regularization, and a gradient regularization method is presented in this paper. This method was verified by processing numerical simulation data and physical model data. 展开更多
关键词 Crosswell seismic tomography gradient regularization method numerical simulation physical model
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Occurrence Regularity and Prediction Model of Underground Pest Adults in Hangzhou District of China
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作者 Wang Daoze Hong Wenying +2 位作者 Wu Yanjun Wang Aijuan Wei Jiqian 《Plant Diseases and Pests》 CAS 2013年第1期1-6,27,共7页
To improve forecasting and sustained control level of underground pests, trapping quantity of underground pests (black cutworm,mole cricket and scar-ab) by lamps and their field dynamics in Hangzhou district from 20... To improve forecasting and sustained control level of underground pests, trapping quantity of underground pests (black cutworm,mole cricket and scar-ab) by lamps and their field dynamics in Hangzhou district from 2005 to 2011 were investigated in the paper. The results showed that different pests had obvious differences in population dynamic. The black cutworm (Agrotis ypsilon) had several damage peaks (late May, late June and late July) and the moth amount in early period was relatively high. The mole cricket ( Gryllotalpa africana) had two damage peaks (late May to early July, early September to mid and late October). The scarab (Anomala corpulenta) had one damage peak (late May to late June). There were periodic changes in total quantity of underground pests among years, and the peak period appeared in the year of 2005, 2007 to 2009 and 2011, respectively. On this basis, temperature, humidity, rainfall and light were used as forecas- ting factors, using the method of stepwise regression, 19 factors with significant correlation were screened out and prediction models for occurrence quantity and oc- currence period of the three pests were established. By using accuracy degree judge model for verification, the score values of prediction model for occurrence quan-tity and occurrence period of the three underground pests were more than 58 and 70, which indicated that the historical coincident rate and prediction accuracy of estabhshed prediction models were good. 展开更多
关键词 Hangzhou district Underground pests Population dynamic Occurrence regularity Prediction model
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Modeling of 3D-structure for regular fragments of low similarity unknown structure proteins
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作者 彭志红 Chen Jie Lin Xiwen Sang Yanchao 《High Technology Letters》 EI CAS 2007年第4期431-435,共5页
Because it is hard to search similar structure for low similarity unknown structure proteins directly from the Protein Data Bank (PDB) database, 3D-structure is modeled in this paper for secondary structure regular ... Because it is hard to search similar structure for low similarity unknown structure proteins directly from the Protein Data Bank (PDB) database, 3D-structure is modeled in this paper for secondary structure regular fragments (α-Helices, β-Strands) of such proteins by the protein secondary structure prediction software, the Basic Local Alignment Search Tool (BLAST) and the side chain construction software SCWRL3. First, the protein secondary structure prediction software is adopted to extract secondary structure fragments from the unknown structure proteins. Then, regular fragments are regulated by BLAST based on comparative modeling, providing main chain configurations. Finally, SCWRL3 is applied to assemble side chains for regular fragments, so that 3D-structure of regular fragments of low similarity unknown structure protein is obtained. Regular fragments of several neurotoxins are used for test. Simulation results show that the prediction errors are less than 0.06nm for regular fragments less than 10 amino acids, implying the simpleness and effectiveness of the proposed method. 展开更多
关键词 low similarity unknown structure regular segment 3D-structure modeling main chain confonnation side chain assembly
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基于非凸与不可分离正则化算法的电容层析成像图像重建 被引量:1
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作者 李宁 朱朋飞 +1 位作者 张立峰 卢栋臣 《化工学报》 EI CSCD 北大核心 2024年第3期836-846,共11页
搅拌器内两相混合是化工生产中常见的现象,电容层析成像(ECT)技术主要对两相分布进行可视化重构,以达到监测的目的。受稀疏贝叶斯学习的启发,提出了一种非凸与不可分离正则化(NNR)算法重建ECT图像。在稀疏先验的基础上引入矩阵低秩特性... 搅拌器内两相混合是化工生产中常见的现象,电容层析成像(ECT)技术主要对两相分布进行可视化重构,以达到监测的目的。受稀疏贝叶斯学习的启发,提出了一种非凸与不可分离正则化(NNR)算法重建ECT图像。在稀疏先验的基础上引入矩阵低秩特性,采用最大后验估计在潜在空间中提出一个新的优化问题,利用对偶变量将潜在空间的目标函数映射到原始空间进行迭代求解,用来恢复同时稀疏与低秩的矩阵。与凸近似L1范数相比,NNR算法可获得更准确的重建图像,同时比非凸可分离方法更容易收敛到全局最优解。为验证NNR算法的重建效果,通过数值仿真与静态实验的方法分别与其他5种算法进行重建对比。结果表明:NNR算法可以有效减少重建伪影,提升中心物体的重建质量,为搅拌器内两相分布提供了高质量的重建算法。 展开更多
关键词 电容层析成像 图像重建 非凸不可分离正则化 稀疏-低秩模型 两相混合
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空间结构模型优化的弹性参数FFT-MA随机建模
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作者 黄国娇 曾繁鑫 +2 位作者 王善涛 张宏兵 蒋甫玉 《石油地球物理勘探》 EI CSCD 北大核心 2024年第5期1121-1131,共11页
快速傅里叶变换滑动平均(FFT-MA)法是一种灵活高效的随机建模方法,在地下介质高分辨率建模、复杂介质非平稳建模和不确定性评价等方面具有重要的应用价值。准确构建空间结构模型是利用FFT-MA方法生成合理的随机模型的关键。然而,以往对F... 快速傅里叶变换滑动平均(FFT-MA)法是一种灵活高效的随机建模方法,在地下介质高分辨率建模、复杂介质非平稳建模和不确定性评价等方面具有重要的应用价值。准确构建空间结构模型是利用FFT-MA方法生成合理的随机模型的关键。然而,以往对FFT-MA方法的研究并未提出准确构建空间结构模型的有效方法。为此,文中提出了一种有效的空间结构模型估计方法。该方法基于反演思想,通过最小化随机模型与测井数据和地震数据的空间结构差异,分别估计空间结构模型的纵向自相关长度和横向自相关长度。同时,为了优化空间结构模型的估计效果,在纵向自相关长度的反演过程中引入边界保护正则化,以提高反演的稳定性。此外,将地震约束引入模型优选以提高随机模型的稳定性。实验结果表明:该方法能够稳定估计地下介质的非平稳空间结构模型,从而建立准确描述复杂储层非平稳空间相关特征的高分辨率随机模型。与基于序贯高斯协模拟的随机建模方法相比,使用空间结构模型优化的FFT-MA随机建模方法能够有效刻画多种复杂地质构造从而实现复杂储层建模。 展开更多
关键词 FFT-MA 方法 空间结构模型 参数反演 边界保护正则化 随机建模 非平稳性建模
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石英脉型钨多金属矿床的扇状成矿实例及找矿模型
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作者 方贵聪 王登红 +6 位作者 黄长帅 杨富强 许以明 冯佐海 李学彪 曾强 严长华 《矿床地质》 CAS CSCD 北大核心 2024年第3期613-628,共16页
石英脉型钨矿床是中国数量最多的钨矿床类型,但保有储量消耗迅速,迫切需要创新找矿模型,指导找矿突破。文章结合二十余年的找矿实践,通过详细分析扇状成矿矿床实例,构建了石英脉型钨矿床新的找矿模型。该模型强调赋矿裂隙为岩浆动力成因... 石英脉型钨矿床是中国数量最多的钨矿床类型,但保有储量消耗迅速,迫切需要创新找矿模型,指导找矿突破。文章结合二十余年的找矿实践,通过详细分析扇状成矿矿床实例,构建了石英脉型钨矿床新的找矿模型。该模型强调赋矿裂隙为岩浆动力成因,在花岗岩体顶部呈扇状分布型式,岩浆期后热液恰在裂隙张开时充填其中而形成扇状成矿系统;提出“就岩找矿”、“就矿找矿”、“就矿找岩”的地质、地球化学和地球物理标志,指导矿床尺度的勘查工程部署。截至目前,该模型已在广东禾尚田钨锡矿床、广西珊瑚钨锡矿床、广西社垌钨钼矿床、江西盘古山钨铋矿床等获得了验证,找矿成效显著。 展开更多
关键词 扇状成矿 成矿规律 找矿模型 花岗岩 石英脉型钨矿床
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基于扩散模型和爬坡趋势分类的风电功率自适应区间预测
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作者 韩丽 程颖洁 +1 位作者 王施琪 陈硕 《电网技术》 EI CSCD 北大核心 2024年第6期2448-2457,I0051-I0054,共14页
扩散模型基于马尔可夫链的概率性质,能够定量描述风电的随机性和不确定性。然而,传统基于扩散模型的时序预测方法以当前输入前一段样本的均值作为基准进行特征缩放,导致预测区间在高峰时段过大、低谷时段过小。因此,提出一种基于扩散模... 扩散模型基于马尔可夫链的概率性质,能够定量描述风电的随机性和不确定性。然而,传统基于扩散模型的时序预测方法以当前输入前一段样本的均值作为基准进行特征缩放,导致预测区间在高峰时段过大、低谷时段过小。因此,提出一种基于扩散模型和爬坡趋势分类的风电功率自适应区间预测方法。首先,利用基于扩散模型的区间预测框架获取初始预测区间。然后,将风电波动过程划分为6种模式,对不同模式下的预测区间采取自适应规整策略,进而获得初始改进区间。接着,针对高出力模式中非爬坡时段的区间带宽不匹配问题,建立爬坡趋势分类评估模型,并结合所属出力模式进行区间修正,获得最终的区间预测结果。最后,实验结果表明所提方法的区间预测效果更优。 展开更多
关键词 扩散模型 自适应规整 波动特征 爬坡趋势分类 区间预测
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基于核机器的加速失效时间模型及其应用
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作者 荣耀华 王江慧 +1 位作者 程维虎 曹美雅 《统计研究》 北大核心 2024年第2期139-148,共10页
加速失效时间模型是一种应用广泛的生存分析模型。本文借助LASSO惩罚剔除冗余预测变量,构建基于核机器的加速失效时间模型,用以刻画预测变量与生存期间的复杂关系。此外,提出一种新的正则化Garrotized核机器估计方法,可以较好地刻画预... 加速失效时间模型是一种应用广泛的生存分析模型。本文借助LASSO惩罚剔除冗余预测变量,构建基于核机器的加速失效时间模型,用以刻画预测变量与生存期间的复杂关系。此外,提出一种新的正则化Garrotized核机器估计方法,可以较好地刻画预测变量与生存期潜在的非线性关系,实现非参数分量中预测变量间交互作用的自动建模,提升模型预测精度。模拟研究表明,与已有的代表性方法相比,本文提出的方法对生存期的预测精度更高,特别是在复杂关系情形下优势更为显著。最后,将该方法应用于胃癌数据分析,利用临床信息和基因表达预测生存期和风险评分。实证结果显示,该方法能为病例基于风险分层的临床精准诊疗方案设计提供有益的参考。 展开更多
关键词 加速失效时间模型 核机器 风险预测 正则化 再生核希尔伯特空间
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辽东-吉南成矿带硼矿成矿规律与找矿探讨
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作者 赵岩 谢园宏 +6 位作者 辛后田 高荣臻 张艳飞 梁帅 陈井胜 杨中柱 吴新伟 《地质与资源》 CAS 2024年第4期493-508,594,共17页
辽东-吉南成矿带是我国最主要的硬岩型硼矿产地.本文在收集辽东-吉南地区前寒武纪地质、胶辽吉造山带等基础地质科研成果和成矿作用研究基础上,总结辽东地区古元古代造山作用与硼矿等成矿事件耦合关系,建立辽东-吉南成矿带硼矿成矿模式... 辽东-吉南成矿带是我国最主要的硬岩型硼矿产地.本文在收集辽东-吉南地区前寒武纪地质、胶辽吉造山带等基础地质科研成果和成矿作用研究基础上,总结辽东地区古元古代造山作用与硼矿等成矿事件耦合关系,建立辽东-吉南成矿带硼矿成矿模式.通过调研后仙峪、翁泉沟和砖庙-杨木杆等典型硼矿床,汇总前人对硼、镁同位素分析结果,重新作图分析.研究认为硼矿经历了早期富集、古元古代造山过程中成矿和后期改造3个主要过程;富镁大理岩和初始富集硼为主要成矿物质来源;基性和超基性岩块在造山变质过程中对富硼流体的圈闭起到了重要作用,也贡献了部分成矿物质;后期变质作用破坏矿体,局部也起到了部分提高矿体品位的作用.同时分析了目前辽东地区制约硼矿找矿的主要因素,认为有待加强古元古代建造构造填图、构造解析,选择合适的勘查手段,并探讨了下一步硼矿找矿思路. 展开更多
关键词 华北克拉通 战略性矿产 辽东-吉南成矿带 硼矿 成矿规律 成矿模式
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基于因果正则化极限学习机的风电功率短期预测方法
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作者 杨茂 张书天 王勃 《电力系统保护与控制》 EI CSCD 北大核心 2024年第11期127-136,共10页
随着风电并网比例的逐年提高,电力系统对风电功率预测的准确性和稳定性提出了更高要求。对于同一风电场而言,为了避免不同特征选择方法所选择的风电场特征子集不同,从因果关系的角度出发,提出了一种基于因果正则化极限学习机(causal reg... 随着风电并网比例的逐年提高,电力系统对风电功率预测的准确性和稳定性提出了更高要求。对于同一风电场而言,为了避免不同特征选择方法所选择的风电场特征子集不同,从因果关系的角度出发,提出了一种基于因果正则化极限学习机(causal regularized extreme learning machine, CRELM)的风电功率短期预测方法。首先将极限学习机(extreme learning machine, ELM)建模为结构因果模型(structural causal model, SCM),在此基础上计算隐藏层神经元与输出层神经元之间的平均因果效应向量。然后将该平均因果效应向量与输出层权重相结合构成因果正则化项,在最小化训练误差的同时最大化网络的因果关系,以进一步提升模型的预测准确性和预测稳定性。最后,以国内蒙西某风电场数据为例,与采用特征选择或不采用特征选择的预测模型相对比,验证了所提方法的有效性和适用性。 展开更多
关键词 特征选择 因果正则化 结构因果模型 平均因果效应向量 极限学习机
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