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基于Input-Output模型的新疆水资源合理配置研究 被引量:2
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作者 刘爽 李莉 荣伟 《江西农业学报》 CAS 2018年第5期101-105,109,共6页
根据2007和2012年新疆统计年鉴和投入产出表等相关资料,利用Input-output模型和水资源结构偏差系数对国民经济各产业的用水效率、用水效益指数等进行了分析。研究表明:2012年新疆各产业水资源利用效率和效益显著提高,但农业用水消耗量... 根据2007和2012年新疆统计年鉴和投入产出表等相关资料,利用Input-output模型和水资源结构偏差系数对国民经济各产业的用水效率、用水效益指数等进行了分析。研究表明:2012年新疆各产业水资源利用效率和效益显著提高,但农业用水消耗量远高于其产出效益,第三产业和生态环境产业的水资源消耗呈现递减趋势。此外,工业和建筑业的水资源配置较为合理。最后,为促进新疆水资源优化配置提出了相应的对策建议。 展开更多
关键词 水资源 合理配置 Input-output模型 新疆
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Adaptive robust output force tracking control of pneumatic cylinder while maximizing/minimizing its stiffness 被引量:4
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作者 孟德远 陶国良 +1 位作者 班伟 钱鹏飞 《Journal of Central South University》 SCIE EI CAS 2013年第6期1510-1518,共9页
The system considered in this work consists of a cylinder which is controlled by a pair of three-way servo valves rather than a four-way one.Therefore,the cylinder output stiffness is independently controllable of the... The system considered in this work consists of a cylinder which is controlled by a pair of three-way servo valves rather than a four-way one.Therefore,the cylinder output stiffness is independently controllable of the output force.A discontinuous projection based adaptive robust controller (ARC) was constructed to achieve high-accuracy output force trajectory tracking for the system.In ARC,on-line parameter adaptation method was adopted to reduce the extent of parametric uncertainties due to the variation of friction parameters,and sliding mode control method was utilized to attenuate the effects of parameter estimation errors,unmodelled dynamics and disturbance.Furthermore,output stiffness maximization/minimization was introduced to fulfill the requirement of many robotic applications.Extensive experimental results were presented to illustrate the effectiveness and the achievable performance of the proposed scheme.For tracking a 0.5 Hz sinusoidal trajectory,maximum tracking error is 4.1 N and average tracking error is 2.2 N.Meanwhile,the output stiffness can be made and maintained near its maximum/minimum. 展开更多
关键词 servo-pneumatic systems output force control cylinder output stiffness sliding mode control adaptive control
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Soft-output stack algorithm with lattice-reduction for MIMO detection
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作者 Yuan Yang Hailin Zhang Junfeng Hue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期197-203,共7页
A computationally efficient soft-output detector with lattice-reduction (LR) for the multiple-input multiple-output (MIMO) systems is proposed. In the proposed scheme, the sorted QR de- composition is applied on t... A computationally efficient soft-output detector with lattice-reduction (LR) for the multiple-input multiple-output (MIMO) systems is proposed. In the proposed scheme, the sorted QR de- composition is applied on the lattice-reduced equivalent channel to obtain the tree structure. With the aid of the boundary control, the stack algorithm searches a small part of the whole search tree to generate a handful of candidate lists in the reduced lattice. The proposed soft-output algorithm achieves near-optimal perfor- mance in a coded MIMO system and the associated computational complexity is substantially lower than that of previously proposed methods. 展开更多
关键词 multiple-input multiple-output (MIMO) soft-output de- tection lattice-reduction stack algorithm.
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Sizing of Energy Storage Systems for Output Smoothing of Renewable Energy Systems 被引量:131
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作者 王成山 于波 +1 位作者 肖峻 郭力 《中国电机工程学报》 EI CSCD 北大核心 2012年第16期I0001-I0026,共26页
光伏、风力发电等可再生能源(renewable energysources,RESs)具有随机性、间歇性等特点。为了抑制RESs输出波动对电网的不利影响,提出了用于平滑RESs发电系统功率输出的储能系统(energy storage system,ESS)容量优化确定方法。... 光伏、风力发电等可再生能源(renewable energysources,RESs)具有随机性、间歇性等特点。为了抑制RESs输出波动对电网的不利影响,提出了用于平滑RESs发电系统功率输出的储能系统(energy storage system,ESS)容量优化确定方法。利用离散傅里叶变换(discrete Fouriertransform,DFT)对RESs输出功率进行频谱分析,基于频谱分析结果,考虑ESS充放电效率、荷电状态(stateofcharge,soc)及RESs发电系统目标功率输出波动率的约束,确定所需ESS最小容量。采用美国华盛顿州实际观测风速数据及日本东北电力公司风电场接入电网20rnin有功功率波动规范(最大波动率为10%),在一风力发电系统中对该方法进行了验证。算例结果表明采用该方法能够以较小的容量将风机输出最大波动率由61.7%降到9.9%。 展开更多
关键词 可再生能源 输出能量 存储系统 能源系统 平滑 RESS 选型 随机波动
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Static Output Feedback Control for Discrete-time Piecewise Linear Systems: an LMI Approach 被引量:7
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作者 DING Da-Wei YANG Guang-Hong 《自动化学报》 EI CSCD 北大核心 2009年第4期337-344,共8页
关键词 Piecewise linear systems piecewise quadratic Lyapunov function Finsler's lemma static output feedback (SOF) linear matrix inequality (LMI)
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Robust H_∞ output feedback controller design for uncertain discrete-time switched systems via switched Lyapunov functions 被引量:3
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作者 Du Dongsheng Jiang Bin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期584-590,共7页
The H∞ output feedback control problem for uncertain discrete-time switched systems is reasearclled. A new characterization of stability and H∞ performance for the switched system under arbitrary switching is obtain... The H∞ output feedback control problem for uncertain discrete-time switched systems is reasearclled. A new characterization of stability and H∞ performance for the switched system under arbitrary switching is obtained by using switched Lyapunov function. Then, based on the characterization, a linear matrix inequality (LMI) approach is developed to design a switched output feedback controller which guarantees the stability and H∞ performance of the closed-loop system. A numerical example is presented to demonstrate the application of the proposed method. 展开更多
关键词 H∞ performance LMI output feedback robustly stable.
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Composite nonlinear feedback control for output regulation problem of linear discrete-time systems with input saturation 被引量:2
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作者 Chongwen Wang Xing Chu Weiyao Lan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期1043-1055,共13页
Transient performance for output regulation problems of linear discrete-time systems with input saturation is addressed by using the composite nonlinear feedback(CNF) control technique. The regulator is designed to ... Transient performance for output regulation problems of linear discrete-time systems with input saturation is addressed by using the composite nonlinear feedback(CNF) control technique. The regulator is designed to be an additive combination of a linear regulator part and a nonlinear feedback part. The linear regulator part solves the regulation problem independently which produces a quick output response but large oscillations. The nonlinear feedback part with well-tuned parameters is introduced to improve the transient performance by smoothing the oscillatory convergence. It is shown that the introduction of the nonlinear feedback part does not change the solvability conditions of the linear discrete-time output regulation problem. The effectiveness of transient improvement is illustrated by a numeric example. 展开更多
关键词 output regulation composite nonlinear feedback in-put saturation transient performance discrete-time system
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Prediction of efficient outputs based on GM(1,N) model and weak DEA efficiency 被引量:2
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作者 Jiefang Wang Sifeng Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第6期933-939,共7页
This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient ou... This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient outputs.The increased outputs are solved by linear programming using data envelopment analysis efficiency theories,wherein a new sample is introduced whose inputs are equal to the budget in the issue No.n + 1 and outputs are forecasted by the GM(1,N) model.The shortcoming in the existing methods that the forecasted efficient outputs may be less than the possible actual outputs according to developing trends of input-output rate in the periods of pre-n is overcome.The new prediction method provides decision-makers with more decisionmaking information,and the initial conditions are easy to be given. 展开更多
关键词 efficient outputs GM(1 N) model data envelopment analysis(DEA) weak DEA efficiency prediction.
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Quantized dynamic output feedback control for networked control systems 被引量:1
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作者 Chong Jiang Dexin Zou +1 位作者 Qingling Zhang Song Guo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1025-1032,共8页
The problem of the quantized dynamic output feedback controller design for networked control systems is mainly discussed. By using the quantized information of the system measurement output and the control input, a no... The problem of the quantized dynamic output feedback controller design for networked control systems is mainly discussed. By using the quantized information of the system measurement output and the control input, a novel networked control system model is described. This model includes many networkinduced features, such as multi-rate sampled-data, quantized signal, time-varying delay and packet dropout. By constructing suitable Lyapunov-Krasovskii functional, a less conservative stabilization criterion is established in terms of linear matrix inequalities. The quantized control strategy involves the updating values of the quantizer parameters μi(i = 1, 2)(μi take on countable sets of values which dependent on the information of the system measurement outputs and the control inputs). Furthermore, a numerical example is given to illustrate the effectiveness of the proposed method. 展开更多
关键词 networked control systems SAMPLED-DATA linear matrix inequalities quantized dynamic output feedback.
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Adaptive output feedback control for uncertain nonholonomic chained systems 被引量:1
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作者 袁占平 王祝萍 陈启军 《Journal of Central South University》 SCIE EI CAS 2010年第3期572-579,共8页
An adaptive output feedback control was proposed to deal with a class of nonholonomic systems in chained form with strong nonlinear disturbances and drift terms. The objective was to design adaptive nonlinear output f... An adaptive output feedback control was proposed to deal with a class of nonholonomic systems in chained form with strong nonlinear disturbances and drift terms. The objective was to design adaptive nonlinear output feedback laws such that the closed-loop systems were globally asymptotically stable, while the estimated parameters remained bounded. The proposed systematic strategy combined input-state-scaling with backstepping technique. The adaptive output feedback controller was designed for a general case of uncertain chained system. Furthermore, one special case was considered. Simulation results demonstrate the effectiveness of the proposed controllers. 展开更多
关键词 adaptive output feedback input-state scaling BACKSTEPPING nonholonomic system
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Exact uncertainty compensation of linear systems by continuous fixed-time output-feedback controller 被引量:1
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作者 SHI Shang ZHANG Guosheng +2 位作者 MIN Huifang HU Yinlong SUN Yonghui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第3期706-715,共10页
This paper studies the fixed-time output-feedback control for a class of linear systems subject to matched uncertainties.To estimate the uncertainties and system states,we design a composite observer which consists of... This paper studies the fixed-time output-feedback control for a class of linear systems subject to matched uncertainties.To estimate the uncertainties and system states,we design a composite observer which consists of a high-order sliding mode observer and a Luenberger observer.Then,a robust output-feedback controller with fixed-time convergence guarantee is constructed.Rigorous theoretical proof shows that with the proposed controller,the system states can converge to zero in fixed-time free of the initial conditions.Finally,simulation comparison with existing algorithms is given.Simulation results verify the effectiveness of the proposed controller in terms of its fixed-time convergence and perfect disturbance rejection. 展开更多
关键词 linear system output feedback matched uncertainty fixed-time control OBSERVER
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Cloud removal of remote sensing image based on multi-output support vector regression 被引量:3
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作者 Gensheng Hu Xiaoqi Sun +1 位作者 Dong Liang Yingying Sun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期1082-1088,共7页
Removal of cloud cover on the satellite remote sensing image can effectively improve the availability of remote sensing images. For thin cloud cover, support vector value contourlet transform is used to achieve multi-... Removal of cloud cover on the satellite remote sensing image can effectively improve the availability of remote sensing images. For thin cloud cover, support vector value contourlet transform is used to achieve multi-scale decomposition of the area of thin cloud cover on remote sensing images. Through enhancing coefficients of high frequency and suppressing coefficients of low frequency, the thin cloud is removed. For thick cloud cover, if the areas of thick cloud cover on multi-source or multi-temporal remote sensing images do not overlap, the multi-output support vector regression learning method is used to remove this kind of thick clouds. If the thick cloud cover areas overlap, by using the multi-output learning of the surrounding areas to predict the surface features of the overlapped thick cloud cover areas, this kind of thick cloud is removed. Experimental results show that the proposed cloud removal method can effectively solve the problems of the cloud overlapping and radiation difference among multi-source images. The cloud removal image is clear and smooth. 展开更多
关键词 remote sensing image cloud removal support vector regression MULTI-output
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Application of multi-outputs LSSVR by PSO to the aero-engine model 被引量:5
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作者 Lu Feng Huang Jinquan Qiu Xiaojie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第5期1153-1158,共6页
Considering the modeling errors of on-board self-tuning model in the fault diagnosis of aero-engine, a new mechanism for compensating the model outputs is proposed. A discrete series predictor based on multi-outputs l... Considering the modeling errors of on-board self-tuning model in the fault diagnosis of aero-engine, a new mechanism for compensating the model outputs is proposed. A discrete series predictor based on multi-outputs least square support vector regression (LSSVR) is applied to the compensation of on-board self-tuning model of aero-engine, and particle swarm optimization (PSO) is used to the kernels selection of multi-outputs LSSVR. The method need not reconstruct the model of aero-engine because of the differences in the individuals of the same type engines and engine degradation after use. The concrete steps for the application of the method are given, and the simulation results show the effectiveness of the algorithm. 展开更多
关键词 AERO-ENGINE on-board self-tuning model multi-outputs least square support vector regression particle swarm optimization.
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Adaptive output-feedback control for MIMO nonlinear systems with time-varying delays using neural networks 被引量:1
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作者 Weisheng Chen Ruihong Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第5期850-858,共9页
An adaptive neural network output-feedback regulation approach is proposed for a class of multi-input-multi-output nonlinear time-varying delayed systems.Both the designed observer and controller are free from time de... An adaptive neural network output-feedback regulation approach is proposed for a class of multi-input-multi-output nonlinear time-varying delayed systems.Both the designed observer and controller are free from time delays.Different from the existing results,this paper need not the assumption that the upper bounding functions of time-delay terms are known,and only a neural network is employed to compensate for all the upper bounding functions of time-delay terms,so the designed controller procedure is more simplified.In addition,the resulting closed-loop system is proved to be semi-globally ultimately uniformly bounded,and the output regulation error converges to a small residual set around the origin.Two simulation examples are provided to verify the effectiveness of control scheme. 展开更多
关键词 neural network output-FEEDBACK nonlinear time-delay systems backstepping.
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Global robust output regulation for a class of affine singular nonlinear systems
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作者 Bomin Huang Lingmei Chen Weiyao Lan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第4期745-755,共11页
The global robust output regulation problem of the singular nonlinear system is investigated. Motivated by the input-output linearization of the normal affine nonlinear system, a global diffeomorphism map is designed ... The global robust output regulation problem of the singular nonlinear system is investigated. Motivated by the input-output linearization of the normal affine nonlinear system, a global diffeomorphism map is designed under the assumption that the singular nonlinear system has a strong relative degree. The global diffeomorphism map transfers the singular nonlinear system into a new singular nonlinear system with a special structure. Attaching an internal model to the new singular nonlinear system yields an augmented singular nonlinear system and the global robust stabilization solution of the augmented system implies the global robust output regulation solution of the original singular nonlinear system. Then the global stabilization problem is solved by some appropriate assumptions and the solvability conditions of the global robust output regulation problem are established. Finally, a simulation example is given to illustrate the design approach. 展开更多
关键词 singular nonlinear system diffeomorphism map output regulation robust control
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Channel capacity of multiple-input multiple-output systems with transmit and receive correlation
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作者 Wang Jun Zhu Shihua +1 位作者 Wang Lei Liu Fang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期21-26,共6页
In order to investigate the impact of channel model parameters on the channel capacity of a multipleinput multiple-output (MIMO) system, a novel method is proposed to explore the channel capacity under Rayleigh fiat... In order to investigate the impact of channel model parameters on the channel capacity of a multipleinput multiple-output (MIMO) system, a novel method is proposed to explore the channel capacity under Rayleigh fiat fading with correlated transmit and receive antennas. The optimal transmitting direction which can achieve maximum channel capacity is derived using random matrices theory. In addition, the closed-form expression for the channel capacity of MIMO systems is given by utilizing the properties of Wishart distribution when SNR is high. Computer simulation results show that the channel capacity is maximized when the antenna spacing increases to a certain point, and furthermore, the larger the scattering angle is, the more quickly the channel capacity converges to its maximum. At high SNR (〉12 dB), the estimation of capacity is close to its true wlue. And, when the same array configuration is adopted both at the transmitter and the receiver, the UCA yields higher channel capacity than ULA. 展开更多
关键词 multiple input multiple output channel capacity spatial correlation channel state information
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Output regulation of singular linear systems with input saturation by composite nonlinear feedback control
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作者 LIN Xiaoyan CHEN Lingmei +1 位作者 LIN Dongyun LAN Weiyao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期834-843,共10页
Composite nonlinear feedback (CNF) control techniquefor tracking control problems is extended to the output regulationproblem of singular linear systems with input saturation. A statefeedback CNF control law and an ... Composite nonlinear feedback (CNF) control techniquefor tracking control problems is extended to the output regulationproblem of singular linear systems with input saturation. A statefeedback CNF control law and an output feedback CNF controllaw are constructed respectively for the output regulation problemof singular linear systems with input saturation. It is shown thatthe output regulation problem by CNF control is solvable underthe same solvability conditions of the output regulation problemby linear control. However, with the virtue of the CNF control, thetransient performance of the closed-loop system can be improvedby carefully designing the linear part and the nonlinear part of theCNF control law. The design procedure and the improvement ofthe transient performance of the closed-loop system are illustratedwith a numerical simulation. 展开更多
关键词 singular linear system input saturation output regula-tion composite nonlinear feedback
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Robust decentralized adaptive output feedback fuzzy controller design and application to AHS
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作者 Yishao Huang Dequn Zhou +2 位作者 Xiaoxin Chen Xueyun Chen Zhengwu Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第5期842-849,共8页
A novel decentralized indirect adaptive output feedback fuzzy controller is developed for a class of large-scale uncertain nonlinear systems using error filtering.By the properly filtering of the observation error dyn... A novel decentralized indirect adaptive output feedback fuzzy controller is developed for a class of large-scale uncertain nonlinear systems using error filtering.By the properly filtering of the observation error dynamics,the strictly positive-real condition is guaranteed to hold such that the proposed output feedback and adaptation mechanisms are practicable in practice owing to the fact that its implementation does not require the observation error vector itself any more,which corrects the impracticable schemes in the previous literature involved.The presented control algorithm can ensure that all the signals of the closed-loop large-scale system keep uniformly ultimately bounded and that the tracking error converges to zero asymptotically.The decentralized output feedback fuzzy controller can be applied to address the longitudinal control problem of a string of vehicles within an automated highway system(AHS) and the effectiveness of the design procedure is supported by simulation results. 展开更多
关键词 large-scale nonlinear system fuzzy control output feedback decentralized control strictly positive real(SPR) condition automated highway system(AHS).
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Robust output regulation problem with prescribed performance for nonlinear strict feedback systems
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作者 ZHU Haichao LAN Weiyao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期1033-1041,共9页
This paper investigates the problem of robust output regulation control with prospected transient property for strict feedback systems.By employing the internal model principle,the robust output regulation problem wit... This paper investigates the problem of robust output regulation control with prospected transient property for strict feedback systems.By employing the internal model principle,the robust output regulation problem with a prospected property can be transformed to a robust stabilization problem with a new output constraint.Then,by constructing the speed function and adopting barrier Lyapunov function technique,the dynamic feedback controller can be designed not only to drive error output of the closed-loop system entering into a prescribed performance bound within a given finite time,but also to achieve that the error output converges to zero asymptotically.The effectiveness of the results is illustrated by a simulation example. 展开更多
关键词 robust output regulation nonlinear system prescribed performance bound speed function finite time
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On-line forecasting model for zinc output based on self-tuning support vector regression and its application
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作者 胡志坤 桂卫华 彭小奇 《Journal of Central South University of Technology》 2004年第4期461-464,共4页
An on-line forecasting model based on self-tuning support vectors regression for zinc output was put forward to maximize zinc output by adjusting operational parameters in the process of imperial smelting furnace. In ... An on-line forecasting model based on self-tuning support vectors regression for zinc output was put forward to maximize zinc output by adjusting operational parameters in the process of imperial smelting furnace. In this model, the mathematical model of support vector regression was converted into the same format as support vector machine for classification. Then a simplified sequential minimal optimization for classification was applied to train the regression coefficient vector α- α* and threshold b. Sequentially penalty parameter C was tuned dynamically through forecasting result during the training process. Finally, an on-line forecasting algorithm for zinc output was proposed. The simulation result shows that in spite of a relatively small industrial data set, the effective error is less than 10% with a remarkable performance of real time. The model was applied to the optimization operation and fault diagnosis system for imperial smelting furnace. 展开更多
关键词 imperial smelting furnace support vectors regression sequential minimal optimization zinc output on-line forecasting
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