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STABILITY OF CERTAIN RINGS OF HIGHEST WEIGHT VECTORS 被引量:1
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作者 邓少强 候自新 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2001年第1期57-62,共6页
The authors prove the stability of the rings of highest weight vectors of the action of Om x GLn on the complex polynomial rings on Cm,n. As an application, the structure of the rings for m = 3 is determined.
关键词 Rational representations Maximal unipotent subgroups Rings of highest weight vectors
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Neurocomputing van der Pauw function for the measurement of a semiconductor's resistivity without use of the learning rate of weight vector regulation
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作者 李宏力 孙以材 +1 位作者 王伟 Harry Hutchinson 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2011年第12期32-39,共8页
Van der Pauw's function is often used in the measurement of a semiconductor's resistivity. However, it is difficult to obtain its value from voltage measurements because it has an implicit form. If it can be express... Van der Pauw's function is often used in the measurement of a semiconductor's resistivity. However, it is difficult to obtain its value from voltage measurements because it has an implicit form. If it can be expressed as a polynomial, a semiconductor's resistivity can be obtained from such measurements. Normally, five orders of the abscissa can provide sufficient precision during the expression of any non-linear function. Therefore, the key is to determine the coefficients of the polynomial. By taking five coefficients as weights to construct a neuronetwork, neurocomputing has been used to solve this problem. Finally, the polynomial expression for van der Pauw's function is obtained. 展开更多
关键词 measurement of the semiconductor's resistivity van der Pauw function reversal development neu-rocomputing polynomial match learning rate of weight vector regulation
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Photovoltaic Models Parameters Estimation Based on Weighted Mean of Vectors 被引量:1
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作者 Mohamed Elnagi Salah Kamel +1 位作者 Abdelhady Ramadan Mohamed F.Elnaggar 《Computers, Materials & Continua》 SCIE EI 2023年第3期5229-5250,共22页
Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy source.This is evident in the advancement of scientific research aimed at improving solar cell performance.Due to the ... Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy source.This is evident in the advancement of scientific research aimed at improving solar cell performance.Due to the non-linear nature of the photovoltaic cell,modeling solar cells and extracting their parameters is one of the most important challenges in this discipline.As a result,the use of optimization algorithms to solve this problem is expanding and evolving at a rapid rate.In this paper,a weIghted meaN oF vectOrs algorithm(INFO)that calculates the weighted mean for a set of vectors in the search space has been applied to estimate the parameters of solar cells in an efficient and precise way.In each generation,the INFO utilizes three operations to update the vectors’locations:updating rules,vector merging,and local search.The INFO is applied to estimate the parameters of static models such as single and double diodes,as well as dynamic models such as integral and fractional models.The outcomes of all applications are examined and compared to several recent algorithms.As well as the results are evaluated through statistical analysis.The results analyzed supported the proposed algorithm’s efficiency,accuracy,and durability when compared to recent optimization algorithms. 展开更多
关键词 Photovoltaic(PV)modules weighted meaN oF vectors algorithm(INFO) renewable energy static PV models dynamic PV models solar energy
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Multi-mode process monitoring based on a novel weighted local standardization strategy and support vector data description 被引量:9
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作者 赵付洲 宋冰 侍洪波 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第11期2896-2905,共10页
There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because the... There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because their presumptions are that sampled-data should obey the single Gaussian distribution or non-Gaussian distribution. In order to solve these problems, a novel weighted local standardization(WLS) strategy is proposed to standardize the multimodal data, which can eliminate the multi-mode characteristics of the collected data, and normalize them into unimodal data distribution. After detailed analysis of the raised data preprocessing strategy, a new algorithm using WLS strategy with support vector data description(SVDD) is put forward to apply for multi-mode monitoring process. Unlike the strategy of building multiple local models, the developed method only contains a model without the prior knowledge of multi-mode process. To demonstrate the proposed method's validity, it is applied to a numerical example and a Tennessee Eastman(TE) process. Finally, the simulation results show that the WLS strategy is very effective to standardize multimodal data, and the WLS-SVDD monitoring method has great advantages over the traditional SVDD and PCA combined with a local standardization strategy(LNS-PCA) in multi-mode process monitoring. 展开更多
关键词 multiple operating modes weighted local standardization support vector data description multi-mode monitoring
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A∞ weight estimates for vector-valued commutators of multilinear fractional integral 被引量:3
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作者 YU Xiao CHEN Jie-cheng ZHANG Yan-dan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第3期335-357,共23页
In this paper, the authors get the Coifman type weighted estimates and weak weighted LlogL estimates for vector-valued generalized commutators of multilinear fractional integral with w ∈ A∞. Furthermore, both the bo... In this paper, the authors get the Coifman type weighted estimates and weak weighted LlogL estimates for vector-valued generalized commutators of multilinear fractional integral with w ∈ A∞. Furthermore, both the boundedness of vector-valued multilinear frac- tional integral and the weak weighted LlogL estimates for vector-valued multilinear fractional integral are also obtained. 展开更多
关键词 vector-VALUED COMMUTATOR multilineax fractional integral weighted.
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Research on Node Classification Based on Joint Weighted Node Vectors
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作者 Li Dai 《Journal of Applied Mathematics and Physics》 2024年第1期210-225,共16页
Node of network has lots of information, such as topology, text and label information. Therefore, node classification is an open issue. Recently, one vector of node is directly connected at the end of another vector. ... Node of network has lots of information, such as topology, text and label information. Therefore, node classification is an open issue. Recently, one vector of node is directly connected at the end of another vector. However, this method actually obtains the performance by extending dimensions and considering that the text and structural information are one-to-one, which is obviously unreasonable. Regarding this issue, a method by weighting vectors is proposed in this paper. Three methods, negative logarithm, modulus and sigmoid function are used to weight-trained vectors, then recombine the weighted vectors and put them into the SVM classifier for evaluation output. By comparing three different weighting methods, the results showed that using negative logarithm weighting achieved better results than the other two using modulus and sigmoid function weighting, and was superior to directly concatenating vectors in the same dimension. 展开更多
关键词 Node Classification Network Embedding Representation Learning weighted vectors Training
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Fault Diagnosis Model Based on Fuzzy Support Vector Machine Combined with Weighted Fuzzy Clustering 被引量:3
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作者 张俊红 马文朋 +1 位作者 马梁 何振鹏 《Transactions of Tianjin University》 EI CAS 2013年第3期174-181,共8页
A fault diagnosis model is proposed based on fuzzy support vector machine (FSVM) combined with fuzzy clustering (FC).Considering the relationship between the sample point and non-self class,FC algorithm is applied to ... A fault diagnosis model is proposed based on fuzzy support vector machine (FSVM) combined with fuzzy clustering (FC).Considering the relationship between the sample point and non-self class,FC algorithm is applied to generate fuzzy memberships.In the algorithm,sample weights based on a distribution density function of data point and genetic algorithm (GA) are introduced to enhance the performance of FC.Then a multi-class FSVM with radial basis function kernel is established according to directed acyclic graph algorithm,the penalty factor and kernel parameter of which are optimized by GA.Finally,the model is executed for multi-class fault diagnosis of rolling element bearings.The results show that the presented model achieves high performances both in identifying fault types and fault degrees.The performance comparisons of the presented model with SVM and distance-based FSVM for noisy case demonstrate the capacity of dealing with noise and generalization. 展开更多
关键词 FUZZY support vector machine FUZZY clustering SAMPLE weight GENETIC algorithm parameter optimization FAULT diagnosis
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基于i-vector局部加权线性判别分析的说话人识别 被引量:7
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作者 王明合 唐振民 张二华 《仪器仪表学报》 EI CAS CSCD 北大核心 2015年第12期2842-2848,共7页
基于i-vector的说话人识别系统通常采用LDA来消除训练和测试语音之间信道失配,不能保证样本在待识别语音近邻区域内具有最佳的分离度,这就使得目标说话人和其近邻间的得分差异较小,进而导致识别准确性下降。针对该问题,提出基于i-vecto... 基于i-vector的说话人识别系统通常采用LDA来消除训练和测试语音之间信道失配,不能保证样本在待识别语音近邻区域内具有最佳的分离度,这就使得目标说话人和其近邻间的得分差异较小,进而导致识别准确性下降。针对该问题,提出基于i-vector局部加权线性判别分析的说话人识别方法(LWLDA)。在计算类内和类间散度时,增加待识别语音近邻样本权重。在此基础上,通过提高待识别语音近邻域局部类间的分辨能力,尽可能减少因信道差异而产生的识别错误。在不同语音库上的实验结果表明:LWLDA在复杂信道环境下能够保持良好的鲁棒性;在交叉信道条件下的识别准确率比LDA平均提高3.6%。 展开更多
关键词 语音处理 说话人识别 身份认证向量 局部加权线性判别分析
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基于weight-pooling词向量的上下文广告推荐算法 被引量:1
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作者 杨长春 王俊 +1 位作者 袁敏 雷晨阳 《计算机应用与软件》 CSCD 2016年第12期224-229,共6页
提出一种基于weight-pooling词向量的上下文广告推荐算法,利用用户访问记录的互信息权重,计算weight-pooling词向量的余弦相似度。该算法改进了传统基于关键词匹配的推荐算法,避免了数据稀疏性和冷启动问题。通过实验分析,基于weightpoo... 提出一种基于weight-pooling词向量的上下文广告推荐算法,利用用户访问记录的互信息权重,计算weight-pooling词向量的余弦相似度。该算法改进了传统基于关键词匹配的推荐算法,避免了数据稀疏性和冷启动问题。通过实验分析,基于weightpooling词向量的上下文广告推荐算法在推荐效果上明显优于传统算法。 展开更多
关键词 词向量 相似度 weight-pooling上下文广告
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Assessment on the Water Resources Carrying Capacity in Karst Area Based on the Cosine Vector Included Angle 被引量:5
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作者 袁子勇 焦树林 +1 位作者 杨萍 金开梅 《Meteorological and Environmental Research》 CAS 2010年第12期1-2,13,共3页
[Objective] The research aimed to assess the water resources carrying capacity in Guizhou Province based on the cosine vector included angle method. [Method] By using the cosine vector included angle method, the index... [Objective] The research aimed to assess the water resources carrying capacity in Guizhou Province based on the cosine vector included angle method. [Method] By using the cosine vector included angle method, the index weight was determined. The projection value of water resources carrying capacity in Guizhou Province was counted by using the multi-objective gray relational projection method. Moreover, the projection value which was counted by the index weight determined by the mean-variance method was as the control. [Result] The projection values which were obtained by two kinds of methods were very close, and the ordering result was consistent. [Conclusion] In the assessment of water resources carrying capacity, it was feasible to use the cosine vector included angle method to determine the index weight. 展开更多
关键词 Cosine vector included angle Index weight Gray relational projection Water resources carrying capacity China
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V-BILIPSCHITZ DETERMINACY OF WEIGHTED HOMOGENEOUS ANALYTIC FUNCTION-GERMS ON WEIGHTED HOMOGENEOUS REAL ANALYTIC VARIETIES 被引量:1
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作者 刘恒兴 张敦穆 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1249-1256,共8页
In this article, we provide estimates for the degree of V bilipschitz determinacy of weighted homogeneous function germs defined on weighted homogeneous analytic variety V satisfying a convenient Lojasiewicz condition... In this article, we provide estimates for the degree of V bilipschitz determinacy of weighted homogeneous function germs defined on weighted homogeneous analytic variety V satisfying a convenient Lojasiewicz condition.The result gives an explicit order such that the geometrical structure of a weighted homogeneous polynomial function germs is preserved after higher order perturbations. 展开更多
关键词 V bilipschitz determinacy weighted homogeneous polynomial function germs controlled vector field weighted homogeneous control functions
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Density Weighted Averaging Operator and Application
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作者 ZHANG Danning YI Pingtao LI Weiwei 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第6期535-540,共6页
Exploring structural characteristics implied in initialdecision making information is an important issue in the process of aggregation. In this paper we provide a new family of aggregation operator called density weig... Exploring structural characteristics implied in initialdecision making information is an important issue in the process of aggregation. In this paper we provide a new family of aggregation operator called density weighted averaging operator(abbreviated as DWA operator), which carries out the aggregation by classification. In this case, not only the hidden structural characteristics can be identified, some commonly known aggregation operators can also be incorporated into the function of the DWA operator. We further discuss the basic properties of this new operator, such as commutativity, idempotency, boundedness and monotonicity withcertain condition. Afterwards, two important issues related to the DWA operator are investigated, including the arguments partition and the determination of density weights. At last a numerical example regarding performance evaluation of employees is developed to illustrate the using of this new operator. 展开更多
关键词 decision making information aggregation density weighted averaging operator density weighting vector
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Molecular weight determination of a newly synthesized guanidinylated disulfide-containing poly(amido amine) by gel permeation chromatography 被引量:3
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作者 Haonan Xing Mei Lu +4 位作者 Lei Xian Jinmin Zhang Tianzhi Yang Li Yang Pingtian Ding 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2017年第3期292-298,共7页
A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). ... A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). Gel permeation chromatography(GPC) was used to evaluate the molecular weight of synthesized CAR-CBA. Polyethyleneimine(PEI) with molecular weight of 25 kDa was adopted as a reference, and polyethylene glycols(PEG) with different molecular weights were used to establish a standard curve for determining the molecular weight of CAR-CBA. The effects of two critical factors, namely columns and eluents,on the molecular weight measurement of CAR-CBA were investigated to optimize the GPC quantitative method. The results showed that Ultrahydrogel columns(120, 250) and HAc–NaAc(0.5 M, pH 4.5) buffer solution were the optimal column and GPC eluent, respectively.The molecular weight of the synthesized CAR-CBA was analyzed by the optimized GPC method and determined to be 24.66 kDa. 展开更多
关键词 Guanidinylated disulfide-containing poly(amido amine) Synthesis Cationic gene delivery vector Molecular weight determination Gel PERMEATION chromatography
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Design and realization of threshold secret sharing scheme with random weights
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作者 Ye Zhenjun Fang Zhenming +1 位作者 Wang Chunfeng Meng Fanzhen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第5期1091-1095,共5页
A new threshold secret sharing scheme is constructed by introducing the concept of share vector, in which the number of shareholders can be adjusted by randomly changing the weights of them. This kind of scheme overco... A new threshold secret sharing scheme is constructed by introducing the concept of share vector, in which the number of shareholders can be adjusted by randomly changing the weights of them. This kind of scheme overcomes the limitation of the static weighted secret sharing schemes that cannot change the weights in the process of carrying out and the deficiency of low efficiency of the ordinary dynamic weighted sharing schemes for its resending process. Thus, this scheme is more suitable to the case that the number of shareholders needs to be changed randomly during the scheme is carrying out. 展开更多
关键词 random weight secret sharing share vector.
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WEIGHTED COMPOSITION OPERATORS BETWEEN DIRICHLET SPACES 被引量:5
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作者 王茂发 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期641-651,共11页
In this article, we study the boundedness of weighted composition operators between different vector-valued Dirichlet spaces. Some sufficient and necessary conditions for such operators to be bounded are obtained exac... In this article, we study the boundedness of weighted composition operators between different vector-valued Dirichlet spaces. Some sufficient and necessary conditions for such operators to be bounded are obtained exactly, which are different completely from the scalar-valued case. As applications, we show that these vector-valued Dirichlet spaces are different counterparts of the classical scalar-valued Dirichlet space and characterize the boundedness of multiplication operators between these different spaces. 展开更多
关键词 vector-valued analytic function Dirichlet space weighted composition op-erator BOUNDEDNESS
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基于子问题有效性引导的多目标进化算法
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作者 孙良旭 李林林 刘国莉 《计算机科学》 北大核心 2025年第10期296-307,共12页
为了解决基于分解多目标进化算法求解具有非常规Pareto前沿(Pareto Front,PF)的多目标优化问题(Multi-Objective Problems,MOPs)出现的性能变差、普适性不高等问题,提出了一种新的基于子问题有效性引导的多目标进化算法(Sub-problem Eff... 为了解决基于分解多目标进化算法求解具有非常规Pareto前沿(Pareto Front,PF)的多目标优化问题(Multi-Objective Problems,MOPs)出现的性能变差、普适性不高等问题,提出了一种新的基于子问题有效性引导的多目标进化算法(Sub-problem Effectiveness Guided Multi-Objective Evolution Algorithm Based on Decomposition,MOEA/D-SEG)。算法扩展了子问题结构并描述权向量在进化过程的表现。通过裂变“高效”子问题实现权向量调整,使算法能够更好地适应不同特征的多目标优化问题,保证求得解集的收敛性和多样性,提高算法求解各类复杂多目标优化问题的能力。通过一系列实验,证明了提出算法在不同特征测试问题上的有效性。通过与其他先进算法进行比较分析,证明了提出算法的优越性。该算法在炼钢-连铸调度问题中的应用进一步验证了算法的实用性。 展开更多
关键词 多目标优化 权向量 子问题 分解
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An improved algorithm for weighting keywords in web documents 被引量:1
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作者 孙双 贺樑 +1 位作者 杨静 顾君忠 《Journal of Shanghai University(English Edition)》 CAS 2008年第3期235-239,共5页
In this paper, an improved algorithm, web-based keyword weight algorithm (WKWA), is presented to weight keywords in web documents. WKWA takes into account representation features of web documents and advantages of t... In this paper, an improved algorithm, web-based keyword weight algorithm (WKWA), is presented to weight keywords in web documents. WKWA takes into account representation features of web documents and advantages of the TF*IDF, TFC and ITC algorithms in order to make it more appropriate for web documents. Meanwhile, the presented algorithm is applied to improved vector space model (IVSM). A real system has been implemented for calculating semantic similarities of web documents. Four experiments have been carried out. They are keyword weight calculation, feature item selection, semantic similarity calculation, and WKWA time performance. The results demonstrate accuracy of keyword weight, and semantic similarity is improved. 展开更多
关键词 improved vector space model (IVSM) representation feature feature item keyword weight semantic similarity
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基于多信息融合的INFO-VMD-CNN的齿轮箱故障诊断方法
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作者 吴胜利 郑子润 邢文婷 《振动与冲击》 北大核心 2025年第13期309-316,共8页
针对齿轮箱振动信号复杂多变,导致现有的齿轮箱故障诊断方法诊断精度不高、较弱故障特征容易被噪声淹没等问题,提出了一种基于向量加权平均优化算法(weighted mean of vectors,INFO)、变分模态分解(variational mode decomposition,VMD... 针对齿轮箱振动信号复杂多变,导致现有的齿轮箱故障诊断方法诊断精度不高、较弱故障特征容易被噪声淹没等问题,提出了一种基于向量加权平均优化算法(weighted mean of vectors,INFO)、变分模态分解(variational mode decomposition,VMD)和卷积神经网络(convolutional neural network,CNN)的齿轮故障诊断方法。该方法首先采用熵权法将不同位置的振动传感器信号信息进行融合,利用INFO对VMD算法中参数进行优化,并设计一个复合评价指标作为参数优化的评价标准,使用奇异峭度差分谱的方法对敏感分量进行重构;其次,从重构的信号中提取时域、频域特征并输入到CNN模型中进行分类;最后通过Shap(Shapley additive explanations)值法对模型输入特征的重要性进行排序,分析不同特征组合对模型分类和特定故障识别的影响。在东南大学行星齿轮数据集上进行验证,结果表明,利用所提特征组合进行故障诊断,CNN模型故障诊断准确率为98.24%,高于其他特征组合,为行星齿轮箱的故障诊断提供了一组有效的特征指标。 展开更多
关键词 行星齿轮箱故障诊断 向量加权平均算法(INFO) 奇异峭度差分谱 卷积神经网络(CNN) 评价指标 Shap值法
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基于第一主向量与子空间加权的改进多重信号分类声源定位技术研究
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作者 赵文 卜雄洙 《仪表技术》 2025年第6期61-65,共5页
针对传统多重信号分类(multiple signal classification,MUSIC)算法在低信噪比环境和小型化麦克风阵列影响下的性能下降问题,提出了一种结合第一主向量法和子空间加权法的改进MUSIC算法。首先利用第一主向量法对传统MUSIC算法进行优化,... 针对传统多重信号分类(multiple signal classification,MUSIC)算法在低信噪比环境和小型化麦克风阵列影响下的性能下降问题,提出了一种结合第一主向量法和子空间加权法的改进MUSIC算法。首先利用第一主向量法对传统MUSIC算法进行优化,得到改进的空间谱函数,以降低噪声对定位精度的影响:其次利用基于双指数模型的最小二乘法修正特征值,并对信号子空间和噪声子空间进行加权处理。仿真结果表明,改进后的MUSIC算法能够有效提升小型化麦克风阵列在低信噪比条件下对相近声源波达方向的估计精度,为声源定位系统的小型化应用提供了新的解决方案。 展开更多
关键词 阵列信号处理 方位估计 多重信号分类算法 第一主向量 子空间加权
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基于WSVM的火电机组能效寻优及运行状态评价 被引量:1
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作者 王志杰 吕当振 +1 位作者 田红 刘帅 《热能动力工程》 北大核心 2025年第2期67-75,共9页
为了提升火电机组在全工况范围内的能效水平,提出了基于加权支持向量机(WSVM)的火电机组能效寻优及运行状态评价方法:首先,利用机组运行数据,依据稳定性判据和样本密度法筛除非稳态及异常工况下的运行数据;其次,采用能效择优方法确定模... 为了提升火电机组在全工况范围内的能效水平,提出了基于加权支持向量机(WSVM)的火电机组能效寻优及运行状态评价方法:首先,利用机组运行数据,依据稳定性判据和样本密度法筛除非稳态及异常工况下的运行数据;其次,采用能效择优方法确定模型训练时的样本权重,利用WSVM建立火电机组能效寻优模型,依据该模型获得火电机组各工况下主要指标及参数最优值;最后,在机组运行过程中,将获得的最优值与过程值进行对比,并通过构建的Mandani模糊评价模型实现对机组运行状态的实时量化评价。通过对某660 MW超临界火电机组的应用实例表明:在30%~100%额定负荷区间,基于WSVM方法获得的最优供电煤耗较聚类算法低0.9~4.8 g/(kW·h),能较好地反映火电机组能效最优状态,为判断机组节能降耗空间提供依据;基于模糊模型的状态评价,可为火电机组运行优化调整提供指导。 展开更多
关键词 火电机组 加权支持向量机 能效 模糊模型 状态评价
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