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Optimization of Fermentation Conditions for Xylanase Production by Aspergillus niger NS-1 被引量:4
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作者 Mengting LIU Juanjuan DU +2 位作者 Yan ZHOU Jiawei HUANG Xin WANG 《Agricultural Biotechnology》 CAS 2016年第1期54-56,共3页
In this study, a xylanase-produeing Aspergillus niger strain, NS-1, was screened and isolated from agricultural and forestry wastes. Based on single-fac- tor experiments, the effects of different carbon sources, compo... In this study, a xylanase-produeing Aspergillus niger strain, NS-1, was screened and isolated from agricultural and forestry wastes. Based on single-fac- tor experiments, the effects of different carbon sources, composite carbon sources, nitrogen sources, calcium carbonate concentrations, initial pH and surfactants on xylanase production by A. niger NS-1 were investigated. The results indicated that the most appropriate carbon source was corncobs ; the best composite carbon source was corncobs + xylan, which was conducive to xylanase secretion; the most suitable nitrogen source was ammonium sulfate. Xylanase activity reached the highest in the medium added with 1.5% calcium carbonate and SDS as a surfactant with an initial pH of 5.0. This study provided the basis for the production of high-activity xylanase. 展开更多
关键词 Aspergillus niger NS-1 XYLANASE optimization Fermentation conditions
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A NEURAL-BASED NONLINEAR L_1-NORM OPTIMIZATION ALGORITHM FOR DIAGNOSIS OF NETWORKS* 被引量:8
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作者 He Yigang (Department of Electrical Engineering, Hunan University, Changsha 410082)Luo Xianjue Qiu Guanyuan(School of Electrical Engineering, Xi’an Jiaotong University, Xi’an 710049) 《Journal of Electronics(China)》 1998年第4期365-371,共7页
Based on exact penalty function, a new neural network for solving the L1-norm optimization problem is proposed. In comparison with Kennedy and Chua’s network(1988), it has better properties.Based on Bandler’s fault ... Based on exact penalty function, a new neural network for solving the L1-norm optimization problem is proposed. In comparison with Kennedy and Chua’s network(1988), it has better properties.Based on Bandler’s fault location method(1982), a new nonlinearly constrained L1-norm problem is developed. It can be solved with less computing time through only one optimization processing. The proposed neural network can be used to solve the analog diagnosis L1 problem. The validity of the proposed neural networks and the fault location L1 method are illustrated by extensive computer simulations. 展开更多
关键词 FAULT DIAGNOSIS L1-norm NEURAL optimization
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A GLOBALLY AND SUPERLINEARLY CONVERGENT TRUST REGION METHOD FOR LC^1 OPTIMIZATION PROBLEMS 被引量:1
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作者 Zhang Liping Lai Yanlian Institute of Applied Mathematics,Academia Sinica,Beijing 100080. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第1期72-80,共9页
A new trust region algorithm for solving convex LC 1 optimization problem is presented.It is proved that the algorithm is globally convergent and the rate of convergence is superlinear under some reasonable assum... A new trust region algorithm for solving convex LC 1 optimization problem is presented.It is proved that the algorithm is globally convergent and the rate of convergence is superlinear under some reasonable assumptions. 展开更多
关键词 LC 1 optimization problem global and superlinear convergence trust region method.
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A Superlinerly Convergent ODE-type Trust Region Algorithm for LC^1 Optimization Problems 被引量:5
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作者 OUYi-gui HOUDing-pi 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第2期140-145,共6页
In this paper, a new trust region algorithm for unconstrained LC1 optimization problems is given. Compare with those existing trust regiion methods, this algorithm has a different feature: it obtains a stepsize at eac... In this paper, a new trust region algorithm for unconstrained LC1 optimization problems is given. Compare with those existing trust regiion methods, this algorithm has a different feature: it obtains a stepsize at each iteration not by soloving a quadratic subproblem with a trust region bound, but by solving a system of linear equations. Thus it reduces computational complexity and improves computation efficiency. It is proven that this algorithm is globally convergent and locally superlinear under some conditions. 展开更多
关键词 LC1 optimization ODE methods trust region algorithm superlinear convergence
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A SUPERLINEARLY CONVERGENT TRUST REGION ALGORITHM FOR LC^1 CONSTRAINED OPTIMIZATION PROBLEMS 被引量:3
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作者 欧宜贵 侯定丕 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期67-80,共14页
In this paper, a new trust region algorithm for nonlinear equality constrained LC1 optimization problems is given. It obtains a search direction at each iteration not by solving a quadratic programming subprobiem with... In this paper, a new trust region algorithm for nonlinear equality constrained LC1 optimization problems is given. It obtains a search direction at each iteration not by solving a quadratic programming subprobiem with a trust region bound, but by solving a system of linear equations. Since the computational complexity of a QP-Problem is in general much larger than that of a system of linear equations, this method proposed in this paper may reduce the computational complexity and hence improve computational efficiency. Furthermore, it is proved under appropriate assumptions that this algorithm is globally and super-linearly convergent to a solution of the original problem. Some numerical examples are reported, showing the proposed algorithm can be beneficial from a computational point of view. 展开更多
关键词 LC1 optimization ODE methods trust region methods superlinear convergence
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Pulmonary Edema and Pleural Effusion Detection Using Efficient Net-V1-B4 Architecture and AdamW Optimizer from Chest X-Rays Images
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作者 Anas AbuKaraki Tawfi Alrawashdeh +4 位作者 Sumaya Abusaleh Malek Zakarya Alksasbeh Bilal Alqudah Khalid Alemerien Hamzah Alshamaseen 《Computers, Materials & Continua》 SCIE EI 2024年第7期1055-1073,共19页
This paper presents a novelmulticlass systemdesigned to detect pleural effusion and pulmonary edema on chest Xray images,addressing the critical need for early detection in healthcare.A new comprehensive dataset was f... This paper presents a novelmulticlass systemdesigned to detect pleural effusion and pulmonary edema on chest Xray images,addressing the critical need for early detection in healthcare.A new comprehensive dataset was formed by combining 28,309 samples from the ChestX-ray14,PadChest,and CheXpert databases,with 10,287,6022,and 12,000 samples representing Pleural Effusion,Pulmonary Edema,and Normal cases,respectively.Consequently,the preprocessing step involves applying the Contrast Limited Adaptive Histogram Equalization(CLAHE)method to boost the local contrast of the X-ray samples,then resizing the images to 380×380 dimensions,followed by using the data augmentation technique.The classification task employs a deep learning model based on the EfficientNet-V1-B4 architecture and is trained using the AdamW optimizer.The proposed multiclass system achieved an accuracy(ACC)of 98.3%,recall of 98.3%,precision of 98.7%,and F1-score of 98.7%.Moreover,the robustness of the model was revealed by the Receiver Operating Characteristic(ROC)analysis,which demonstrated an Area Under the Curve(AUC)of 1.00 for edema and normal cases and 0.99 for effusion.The experimental results demonstrate the superiority of the proposedmulti-class system,which has the potential to assist clinicians in timely and accurate diagnosis,leading to improved patient outcomes.Notably,ablation-CAM visualization at the last convolutional layer portrayed further enhanced diagnostic capabilities with heat maps on X-ray images,which will aid clinicians in interpreting and localizing abnormalities more effectively. 展开更多
关键词 Image classification decision support system EfficientNet-V1-B4 AdamW optimizer pulmonary edema pleural effusion chest X-rays
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Performance Optimization of Torque Converters Based on Modified 1D Flow Model 被引量:3
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作者 吴光强 王立军 《Journal of Donghua University(English Edition)》 EI CAS 2012年第5期380-384,共5页
A methodology for performance optimization of torque converters is put forward based on the one-dimensional (1D) flow model. It is found that the inaccuracy of 1D flow model for predicting hydraulic performance at the... A methodology for performance optimization of torque converters is put forward based on the one-dimensional (1D) flow model. It is found that the inaccuracy of 1D flow model for predicting hydraulic performance at the low speed ratio is mainly caused by the separation phenomenon at the stator cascade which is induced by large flow impinging at the pressure side of the stator blades. A semi-empirical separation model is presented and incorporated to the original 1D flow model. It is illustrated that the improved model is able to predict the circumferential velocity components accurately, which can be applied to performance optimization. Then, the Pareto front is obtained by using the genetic algorithm (GA) in order to inspect the coupled relationship among stalling impeller torque capacity, stalling torque ratio and efficiency. The efficiency is maximized on the premise that a target stalling impeller torque capacity and torque ratio are achieved. Finally, the optimized result is verified by the computational fluid dynamics(CFD) simulation, which indicates that the maximal efficiency is increased by 0.96%. 展开更多
关键词 multi-objective optimization torque converter separation flow Pareto front one-dimensional 1 D) flow model
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A FILTER-TRUST-REGION METHOD FOR LC^1 UNCONSTRAINED OPTIMIZATION AND ITS GLOBAL CONVERGENCE 被引量:1
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作者 ZhenghaoYang Wenyu Sun Chuangyin Dang 《Analysis in Theory and Applications》 2008年第1期55-66,共12页
In this paper we present a filter-trust-region algorithm for solving LC1 unconstrained optimization problems which uses the second Dini upper directional derivative. We establish the global convergence of the algorith... In this paper we present a filter-trust-region algorithm for solving LC1 unconstrained optimization problems which uses the second Dini upper directional derivative. We establish the global convergence of the algorithm under reasonable assumptions. 展开更多
关键词 nonsmooth optimization filter method trust region algorithm global conver- gence LC1 optimization
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Enhancing Human Action Recognition with Adaptive Hybrid Deep Attentive Networks and Archerfish Optimization
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作者 Ahmad Yahiya Ahmad Bani Ahmad Jafar Alzubi +3 位作者 Sophers James Vincent Omollo Nyangaresi Chanthirasekaran Kutralakani Anguraju Krishnan 《Computers, Materials & Continua》 SCIE EI 2024年第9期4791-4812,共22页
In recent years,wearable devices-based Human Activity Recognition(HAR)models have received significant attention.Previously developed HAR models use hand-crafted features to recognize human activities,leading to the e... In recent years,wearable devices-based Human Activity Recognition(HAR)models have received significant attention.Previously developed HAR models use hand-crafted features to recognize human activities,leading to the extraction of basic features.The images captured by wearable sensors contain advanced features,allowing them to be analyzed by deep learning algorithms to enhance the detection and recognition of human actions.Poor lighting and limited sensor capabilities can impact data quality,making the recognition of human actions a challenging task.The unimodal-based HAR approaches are not suitable in a real-time environment.Therefore,an updated HAR model is developed using multiple types of data and an advanced deep-learning approach.Firstly,the required signals and sensor data are accumulated from the standard databases.From these signals,the wave features are retrieved.Then the extracted wave features and sensor data are given as the input to recognize the human activity.An Adaptive Hybrid Deep Attentive Network(AHDAN)is developed by incorporating a“1D Convolutional Neural Network(1DCNN)”with a“Gated Recurrent Unit(GRU)”for the human activity recognition process.Additionally,the Enhanced Archerfish Hunting Optimizer(EAHO)is suggested to fine-tune the network parameters for enhancing the recognition process.An experimental evaluation is performed on various deep learning networks and heuristic algorithms to confirm the effectiveness of the proposed HAR model.The EAHO-based HAR model outperforms traditional deep learning networks with an accuracy of 95.36,95.25 for recall,95.48 for specificity,and 95.47 for precision,respectively.The result proved that the developed model is effective in recognizing human action by taking less time.Additionally,it reduces the computation complexity and overfitting issue through using an optimization approach. 展开更多
关键词 Human action recognition multi-modal sensor data and signals adaptive hybrid deep attentive network enhanced archerfish hunting optimizer 1D convolutional neural network gated recurrent units
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Approximation methods of mixed l_1/H_2 optimization problems for MIMO discrete-time systems
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作者 李昇平 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第3期319-326,共8页
The mixed l1/H2 optimization problem for MIMO (multiple input-multiple output) discrete-time systems is considered. This problem is formulated as minimizing the l1-norm of a closed-loop transfer matrix while maintaini... The mixed l1/H2 optimization problem for MIMO (multiple input-multiple output) discrete-time systems is considered. This problem is formulated as minimizing the l1-norm of a closed-loop transfer matrix while maintaining the H2-norm of another closed-loop transfer matrix at prescribed level. The continuity property of the optimal value in respect to changes in the H2-norm constraint is studied. The existence of the optimal solutions of mixed l1/H2 problem is proved. Because the solution of the mixed l1/H2 problem is based on the scaled-Q method, it avoids the zero interpolation difficulties. The convergent upper and lower bounds can be obtained by solving a sequence of finite dimensional nonlinear programming for which many efficient numerical optimization algorithms exist. 展开更多
关键词 MIMO system discrete-time systems mixed l1/H2 optimization.
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Optimization on Extraction Conditions of Flavonoids from Edgeworthia chrysantha Lind1.
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作者 Pengfei CAO Huafen WU Yinhua CHEN 《Agricultural Biotechnology》 CAS 2020年第4期159-167,共9页
[Objectives]The extraction conditions of flavonoids from flowers of Edgeworthia chrysantha Lind1.were optimized.[Methods]With ethanol as an extraction agent,firstly by single-factor tests,the best levels of ethanol co... [Objectives]The extraction conditions of flavonoids from flowers of Edgeworthia chrysantha Lind1.were optimized.[Methods]With ethanol as an extraction agent,firstly by single-factor tests,the best levels of ethanol concentration,material-to-liquid ratio,extraction temperature and extraction time were determined.Then the optimal extraction conditions were determined through the quadratic orthogonal regression rotatable design.[Results]The optimal extraction conditions for flavonoids from E.chrysantha were∶material-to-liquid ratio 1∶15.4,extraction temperature 75℃,extraction time 120 min and ethanol concentration 75%,with which the highest yield of flavonoids was 6.02 mg/g.[Conclusions]This study provides a theoretical basis for the further development and utilization of E.chrysantha flowers. 展开更多
关键词 Edgeworthia chrysantha Lind1. Flavonoid Extraction process optimization
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Simulating Particle Swarm Optimization Algorithm to Estimate Likelihood Function of ARMA(1, 1) Model
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作者 Basad Ali Hussain Al-sarray 《Journal of Mathematics and System Science》 2015年第10期399-410,共12页
This paper present a simulation study of an evolutionary algorithms, Particle Swarm Optimization PSO algorithm to optimize likelihood function of ARMA(1, 1) model, where maximizing likelihood function is equivalent ... This paper present a simulation study of an evolutionary algorithms, Particle Swarm Optimization PSO algorithm to optimize likelihood function of ARMA(1, 1) model, where maximizing likelihood function is equivalent to maximizing its logarithm, so the objective function 'obj.fun' is maximizing log-likelihood function. Monte Carlo method adapted for implementing and designing the experiments of this simulation. This study including a comparison among three versions of PSO algorithm “Constriction coefficient CCPSO, Inertia weight IWPSO, and Fully Informed FIPSO”, the experiments designed by setting different values of model parameters al, bs sample size n, moreover the parameters of PSO algorithms. MSE used as test statistic to measure the efficiency PSO to estimate model. The results show the ability of PSO to estimate ARMA' s parameters, and the minimum values of MSE getting for COPSO. 展开更多
关键词 Particle Swarm optimization algorithm Likelihood function ARMA(1 1 Model
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0-1背包问题上界的快速计算方法
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作者 王正元 《火箭军工程大学学报》 2025年第1期31-40,共10页
为提高0-1背包问题上界求解的速度与精确度,分析了拉格朗日松弛方法构造的精确0-1背包问题上界模型,建立了该模型的快速求解算法,证明了精确0-1背包问题上界是拉格朗日乘子的凸函数。由此,提出了精确0-1背包问题最小上界的求解方法,证... 为提高0-1背包问题上界求解的速度与精确度,分析了拉格朗日松弛方法构造的精确0-1背包问题上界模型,建立了该模型的快速求解算法,证明了精确0-1背包问题上界是拉格朗日乘子的凸函数。由此,提出了精确0-1背包问题最小上界的求解方法,证明了精确0-1背包问题上界是物品数的单峰函数,且0-1背包问题的上界恰好等于物品数为关键物品数(关键物品数-1)时精确0-1背包问题最小上界的最大值。结果表明:该计算方法所需计算量与背包问题物品数成比例,计算速度较快,上界相对较小。通过6500例不同上界计算实验对比,提出的上界计算所需时间约为其他较优算法的15.1%;上界占优比例94.29%,而其他较优算法占优比例仅68.71%。进一步表明该上界算法可以快速构造较好的近似解,从而降低0-1背包问题的维数。 展开更多
关键词 组合优化问题 0-1背包问题 上界 精确0-1背包问题 拉格朗日松弛
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基于交替惩罚基的大规模MIMO低复杂度1-bit预编码算法
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作者 褚衍明 王亚军 《通信技术》 2025年第3期270-276,共7页
1-bit恒定包络(Constant Envelope,CE)预编码能够显著降低大规模多用户多输入多输出(Multi-user Multiple-input Multiple-output,MU-MIMO)系统中硬件功耗和成本,因此成为当下的研究热点。为了设计更低复杂度的1-bit恒定包络预编码算法... 1-bit恒定包络(Constant Envelope,CE)预编码能够显著降低大规模多用户多输入多输出(Multi-user Multiple-input Multiple-output,MU-MIMO)系统中硬件功耗和成本,因此成为当下的研究热点。为了设计更低复杂度的1-bit恒定包络预编码算法,需要解决一个非凸组合优化问题,并且预编码因子和预编码向量是耦合在一起的。为了解决这一难题,定义了一种新的点乘等价约束(Dot Product Equivalent Constraint,DPEC)来将原始非凸组合优化问题转化为凸优化问题,并提出了交替惩罚基(Alternate Penalty Basis,APB)算法来更新对偶变量和目标变量。通过仿真实验证明,APB算法能够获得更快的收敛速度及更低的误码率。 展开更多
关键词 大规模多用户多输入多输出系统 恒定包络预编码 1-bit预编码 非凸组合优化问题
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结合L^1拟合项的Chan-Vese模型 被引量:9
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作者 唐利明 方壮 +2 位作者 向长城 黄大荣 陈世强 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2015年第9期1707-1715,共9页
为了提高Chan-Vese(CV)模型对椒盐噪声的鲁棒性,提出一个结合L1拟合项的CV模型.首先采用L1拟合和L2拟合的线性组合构造一个新的拟合项,然后通过调整这2个拟合的权重以提升该模型对不同噪声图像分割的灵活性,最后利用交替迭代算法对模型... 为了提高Chan-Vese(CV)模型对椒盐噪声的鲁棒性,提出一个结合L1拟合项的CV模型.首先采用L1拟合和L2拟合的线性组合构造一个新的拟合项,然后通过调整这2个拟合的权重以提升该模型对不同噪声图像分割的灵活性,最后利用交替迭代算法对模型进行求解.采用被不同噪声污染的人造图像和自然图像进行实验的结果表明,该模型对噪声图像可以取得较好的分割结果,并且对于椒盐噪声污染图像的分割,比CV模型、LBF模型和VFCMS模型更具优势. 展开更多
关键词 图像分割 CHAN-VESE模型 椒盐噪声 高斯噪声 L^1范数
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集值L^1-极限鞅的集值鞅逼近及其收敛性 被引量:6
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作者 薛红 施雨 聂赞坎 《应用概率统计》 CSCD 北大核心 1999年第4期397-401,共5页
本文证明了集值L~1-极限鞅的集值鞅逼近定理,并利用此结果以及集值鞅的收敛性结果讨论了集值L~1-极限鞅的收敛性.
关键词 集值L^1-极限鞅 集值鞅逼近 随机过程 收敛性
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基于观测器的l^1鲁棒故障检测方法 被引量:2
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作者 方华京 《控制理论与应用》 EI CAS CSCD 北大核心 2001年第1期36-40,共5页
基于参数化的控制系统输出观测器 ,将鲁棒控制理论中的l1最优化方法用于故障检测技术 ,提出一种新的控制系统鲁棒故障检测方法 .通过求解一个混合 0 1型整数线性规划问题 ,可得出l1优化残差函数 .
关键词 故障检测 鲁棒 L^1最优化 鲁棒控制理论 观测器 线性规划
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基于L^1拟合与光滑正则化的图像去噪声问题的半光滑性分析 被引量:1
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作者 林玲 杨余飞 《湖南师范大学自然科学学报》 EI CAS 北大核心 2006年第2期32-34,共3页
基于L1拟合与光滑正则化的图像去噪声问题能够转化为一个非光滑方程.在此基础上,证明了非光滑方程是强半光滑的,因而解此方程的广义牛顿法具有局部二次收敛性.
关键词 广义牛顿法 二次收敛性 图像去噪 L^1拟合
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M/M/1排队模型的l^1动态解及其稳定性 被引量:7
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作者 李扬荣 《应用泛函分析学报》 CSCD 2000年第2期150-154,共5页
运用算子半群理论证明了 M/M/1排队模型的 l1动态解的稳定性和正等距性 .
关键词 M/M/1排队模型 等距半群 稳定性 L^1动态解 正等距性
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l^1鲁棒辨识:一种递推插值方法 被引量:4
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作者 李昇平 《控制理论与应用》 EI CAS CSCD 北大核心 2002年第6期932-936,共5页
针对l1鲁棒辨识不能有效利用试验数据和进行在线辨识的问题 ,提出了一种在线递推插值辨识方法 .用几何方法描述试验信息 ,利用系统可行集与新的试验信息所构成的半空间的包含关系判断数据信息 ,有效地利用了试验数据 ,提高了辨识精度 .... 针对l1鲁棒辨识不能有效利用试验数据和进行在线辨识的问题 ,提出了一种在线递推插值辨识方法 .用几何方法描述试验信息 ,利用系统可行集与新的试验信息所构成的半空间的包含关系判断数据信息 ,有效地利用了试验数据 ,提高了辨识精度 .同时提出了一种新的计算辨识误差紧界的方法 .仿真结果表明了算法的有效性和可行性 . 展开更多
关键词 l^1鲁棒辨识 递推插值方法 系统辨识 模型集 递推算法
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