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Adaptive Optimal Discrete-Time Output-Feedback Using an Internal Model Principle and Adaptive Dynamic Programming 被引量:1
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作者 Zhongyang Wang Youqing Wang Zdzisław Kowalczuk 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期131-140,共10页
In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed metho... In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed method, termed as IMP-ADP, does not require complete state feedback-merely the measurement of input and output data. More specifically, based on the IMP, the output control problem can first be converted into a stabilization problem. We then design an observer to reproduce the full state of the system by measuring the inputs and outputs. Moreover, this technique includes both a policy iteration algorithm and a value iteration algorithm to determine the optimal feedback gain without using a dynamic system model. It is important that with this concept one does not need to solve the regulator equation. Finally, this control method was tested on an inverter system of grid-connected LCLs to demonstrate that the proposed method provides the desired performance in terms of both tracking and disturbance rejection. 展开更多
关键词 Adaptive dynamic programming(ADP) internal model principle(IMP) output feedback problem policy iteration(PI) value iteration(VI)
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A 3D convolutional neural network model with multiple outputs for simultaneously estimating the reactive transport parameters of sandstone from its CT images
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作者 Haiying Fu Shuai Wang +3 位作者 Guicheng He Zhonghua Zhu Qing Yu Dexin Ding 《Artificial Intelligence in Geosciences》 2024年第1期310-319,共10页
Porosity,tortuosity,specific surface area(SSA),and permeability are four key parameters of reactive transport modeling in sandstone,which are important for understanding solute transport and geochemical reaction pro-c... Porosity,tortuosity,specific surface area(SSA),and permeability are four key parameters of reactive transport modeling in sandstone,which are important for understanding solute transport and geochemical reaction pro-cesses in sandstone aquifers.These four parameters reflect the characteristics of pore structure of sandstone from different perspectives,and the traditional empirical formulas cannot make accurate predictions of them due to their complexity and heterogeneity.In this paper,eleven types of sandstone CT images were firstly segmented into numerous subsample images,the porosity,tortuosity,SSA,and permeability of the subsamples were calculated,and the dataset was established.The 3D convolutional neural network(CNN)models were subse-quently established and trained to predict the key reactive transport parameters based on subsample CT images of sandstones.The results demonstrated that the 3D CNN model with multiple outputs exhibited excellent prediction ability for the four parameters compared to the traditional empirical formulas.In particular,for the prediction of tortuosity and permeability,the 3D CNN model with multiple outputs even showed slightly better prediction ability than its single-output variant model.Additionally,it demonstrated good generalization per-formance on sandstone CT images not included in the training dataset.The study showed that the 3D CNN model with multiple outputs has the advantages of simplifying operation and saving computational resources,which has the prospect of popularization and application. 展开更多
关键词 Reactive transport CNN model with multiple outputs SANDSTONE TORTUOSITY PERMEABILITY
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The Impact of The Three-Dimensional Cultivation Model on the Development of the Suzhou Tea Industry:Estimating Value of Output Per Acre and Diversified Sales Models
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作者 Shan Hao 《Proceedings of Business and Economic Studies》 2024年第3期126-132,共7页
This article explores the impact of the three-dimensional cultivation mode on the development of the Suzhou tea industry,focusing on the diversified estimation of the value of output per acre and sales mode.It introdu... This article explores the impact of the three-dimensional cultivation mode on the development of the Suzhou tea industry,focusing on the diversified estimation of the value of output per acre and sales mode.It introduces the history and traditional cultivation practices of tea in Suzhou,as well as the current challenges and problems faced by the industry.An in-depth analysis was conducted on the overview and improvement plans of the three-dimensional cultivation mode,covering relevant technical methods.Based on this analysis,the impact of the three-dimensional cultivation on the value of output per acre was studied and predicted.Its potential and advantages were explored and compared with the effectiveness of traditional cultivation models.Additionally,the impact of the three-dimensional cultivation mode on sales was analyzed,examining its market adaptability and competitiveness,as well as its advantages in expanding sales channels and market coverage.The study also focused on the promoting effect of diversified sales models on the Suzhou tea industry,including direct consumption market development,tea processing product development and promotion,and the integration of tea culture and the tourism industry.To ensure sustainable development,the article evaluates the environmental impact,economic feasibility,social benefits,and farmer benefits of the three-dimensional cultivation model.Finally,the prospects for the development of the Suzhou tea industry were discussed,and the positioning and response strategies of the threedimensional cultivation model were proposed. 展开更多
关键词 Suzhou tea industry Stereoscopic cultivation mode Value of output per acre Sales model DIVERSIFICATION
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湖南省农业生态效率评价研究——基于SBM-undesirable模型与CCR模型的对比分析 被引量:30
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作者 刘志成 张晨成 《中南林业科技大学学报(社会科学版)》 2015年第6期32-36,66,共6页
湖南省是农业大省,农业生态效率是农业经济增长与环境协调发展的真实反映,将农业面源污染CODcr、TN、TP的排放量作为湖南省农业生态效率非期望产出的考量,分别运用dea-ccr模型和sbmundesirable模型对湖南省及14个市区2004-2013年的农业... 湖南省是农业大省,农业生态效率是农业经济增长与环境协调发展的真实反映,将农业面源污染CODcr、TN、TP的排放量作为湖南省农业生态效率非期望产出的考量,分别运用dea-ccr模型和sbmundesirable模型对湖南省及14个市区2004-2013年的农业生态效率进行测算对比分析,结果表明导致农业生态效率损失的主要原因是农业化肥使用过剩、农业用水消耗较大和农业污染问题三方面。最后为保障湖南省农业高效、生态、环保、协调、可持续发展,给出了相关措施及建议。 展开更多
关键词 农业生态效率 非期望产出 SBM模型 CCR模型
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基于SBM-undesirable模型的综合运输效率评价 被引量:18
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作者 宋京妮 吴群琪 +2 位作者 孙启鹏 包旭 杜凯 《交通运输系统工程与信息》 EI CSCD 北大核心 2015年第5期32-38,共7页
综合运输效率高低是衡量运输结构是否合理、方式间是否协调的重要依据.引入SBM-undesirable模型,基于时序演变,系统分析了1979~2012年中国的综合运输效率,并对投入产出要素作定量调整.结果表明,非期望产出对综合运输效率具有显著负影响... 综合运输效率高低是衡量运输结构是否合理、方式间是否协调的重要依据.引入SBM-undesirable模型,基于时序演变,系统分析了1979~2012年中国的综合运输效率,并对投入产出要素作定量调整.结果表明,非期望产出对综合运输效率具有显著负影响;1979~2012年中国的综合运输效率呈"凹"字形波动,均值为0.68,其中1999年效率值最低,不及均值一半;从分解效率看,综合运输效率同时受纯技术效率与规模效率的双重影响,且纯技术效率的制约力略强于规模效率,整体呈"综合效率≤纯技术效率≤规模效率";运输从业人员、铁路机车拥有量及死亡人数是影响综合运输效率的前三个重要因素.因此,调整运输资源结构、减少非期望产出和提高技术效率是提升综合运输效率的现实途径. 展开更多
关键词 综合交通运输 运输效率测度 sbm-undesirable模型 运输系统 非期望产出
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A Model for Retrieval of Dual Linear Polarization Radar Fields from Model Simulation Outputs 被引量:5
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作者 刘黎平 张鹏飞 +1 位作者 孔凡铀 刘瞬 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第5期711-719,共9页
An algorithm for retrieving polarimetric variables from numerical model fields is developed. By using this technique, radar reflectivity at horizontal polarization~ differential reflectivity, specific differential pha... An algorithm for retrieving polarimetric variables from numerical model fields is developed. By using this technique, radar reflectivity at horizontal polarization~ differential reflectivity, specific differential phase shift and correlation coefficients between the horizontal and vertical polarization signals at zero lag can be derived from rain, snow and hail contents of numerical model outputs. Effects of environmental temperature and the melting process on polarimetric variables are considered in the algorithm. The algorithm is applied to the Advanced Regional Prediction System (ARPS) model simulation results for a hail storm. The spatial distributions of the derived parameters are reasonable when compared with observational knowledge. This work provides a forward model for assimilation of dual linear polarization radar data into a mesoscale model. 展开更多
关键词 polarimetric radar retrieval of polarimetric variables model output
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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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Pattern-Moving-Based Parameter Identification of Output Error Models with Multi-Threshold Quantized Observations 被引量:2
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作者 Xiangquan Li Zhengguang Xu +1 位作者 Cheng Han Ning Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第3期1807-1825,共19页
This paper addresses a modified auxiliary model stochastic gradient recursive parameter identification algorithm(M-AM-SGRPIA)for a class of single input single output(SISO)linear output error models with multi-thresho... This paper addresses a modified auxiliary model stochastic gradient recursive parameter identification algorithm(M-AM-SGRPIA)for a class of single input single output(SISO)linear output error models with multi-threshold quantized observations.It proves the convergence of the designed algorithm.A pattern-moving-based system dynamics description method with hybrid metrics is proposed for a kind of practical single input multiple output(SIMO)or SISO nonlinear systems,and a SISO linear output error model with multi-threshold quantized observations is adopted to approximate the unknown system.The system input design is accomplished using the measurement technology of random repeatability test,and the probabilistic characteristic of the explicit metric value is employed to estimate the implicit metric value of the pattern class variable.A modified auxiliary model stochastic gradient recursive algorithm(M-AM-SGRA)is designed to identify the model parameters,and the contraction mapping principle proves its convergence.Two numerical examples are given to demonstrate the feasibility and effectiveness of the achieved identification algorithm. 展开更多
关键词 Pattern moving multi-threshold quantized observations output error model auxiliary model parameter identification
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Application of Gray Metabolic Model in the Prediction of the Cotton Output in China 被引量:2
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作者 ZHOU Zu-liang YIN Chun-wu 《Asian Agricultural Research》 2011年第1期1-2,6,共3页
In order to forecast the cotton output of China in the year 2011, Gray Metabolic Forecast Model is established based on both the Gray Forecast Model and the Metabolic Theory. According to the actual situation, forecas... In order to forecast the cotton output of China in the year 2011, Gray Metabolic Forecast Model is established based on both the Gray Forecast Model and the Metabolic Theory. According to the actual situation, forecast results of conventional GM (1, 1) Model and Metabolism GM (1, 1) Model are analyzed, showing that Metabolic Forecast Model has higher precision than the conventional forecast model. Therefore, Metabolism GM (1, 1) Model is used to forecast the cotton output of China in the year 2011, which is 614 968.3 thousand tons. 展开更多
关键词 Gray system GM(1 1)model Cotton output China
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Prediction Model of Data Envelopment Analysis with Undesirable Outputs 被引量:2
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作者 边馥萍 范宇 《Transactions of Tianjin University》 EI CAS 2004年第1期34-38,共5页
Data envelopment analysis (DEA) has become a standard non parametric approach to productivity analysis, especially to relative efficiency analysis of decision making units (DMUs). Extended to the prediction field, it ... Data envelopment analysis (DEA) has become a standard non parametric approach to productivity analysis, especially to relative efficiency analysis of decision making units (DMUs). Extended to the prediction field, it can solve the prediction problem with multiple inputs and outputs which can not be solved easily by the regression analysis method.But the traditional DEA models can not solve the problem with undesirable outputs,so in this paper the inherent relationship between goal programming and the DEA method based on the relationship between multiple goal programming and goal programming is explored,and a mixed DEA model which can make all factors of inputs and undesirable outputs decrease in different proportions is built.And at the same time,all the factors of desirable outputs increase in different proportions. 展开更多
关键词 data envelopment analysis(DEA) undesirable outputs multiple goal programming mixed DEA model PREDICTION
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Static output feedback stabilization for second-order singular systems using model reduction methods 被引量:1
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作者 Zheng WANG Yuhao CONG Xiulin HU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第3期457-466,共10页
In this paper,the static output feedback stabilization for large-scale unstable second-order singular systems is investigated.First,the upper bound of all unstable eigenvalues of second-order singular systems is deriv... In this paper,the static output feedback stabilization for large-scale unstable second-order singular systems is investigated.First,the upper bound of all unstable eigenvalues of second-order singular systems is derived.Then,by using the argument principle,a computable stability criterion is proposed to check the stability of secondorder singular systems.Furthermore,by applying model reduction methods to original systems,a static output feedback design algorithm for stabilizing second-order singular systems is presented.A simulation example is provided to illustrate the effectiveness of the design algorithm. 展开更多
关键词 second-order singular system static output feedback model reduction method argument principle
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基于SBM-Undesirable模型的省际农业用水效率比较及节水潜力研究 被引量:4
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作者 王普查 瞿彤 金姗姗 《湖北农业科学》 2018年第22期171-176,共6页
为缓解中国农业用水短缺与污染状况,落实国家水安全战略和保证粮食安全,运用考虑非期望产出的SBM-Undesirable模型,比较研究了中国省际农业用水效率和农业用水优化路径。从全要素的角度出发,在识别主要影响农业用水效率因素的基础上,设... 为缓解中国农业用水短缺与污染状况,落实国家水安全战略和保证粮食安全,运用考虑非期望产出的SBM-Undesirable模型,比较研究了中国省际农业用水效率和农业用水优化路径。从全要素的角度出发,在识别主要影响农业用水效率因素的基础上,设计模型的投入指标并测算2011—2014年中国大陆31个省(区、市)的农业用水效率。结果表明,中国农业用水效率总体呈上升趋势,但仍然具有较大的提升空间,各个省(区、市)的农业用水效率呈现不同的发展趋势,新疆、江苏、广东等省份的农业用水效率提升空间大,具有很大的节水潜力。基于农业用水效率的实证结果和污染排放指标,对未达到农业用水效率有效前沿面的25个省份进行聚类分析,将25个省份的农业用水方式分为低农业用水效率-低污染排放、低农业用水效率-高污染排放类型、高农业用水效率-低污染排放类型和高农业用水效率-高污染排放类型四类,并分别提出了农业用水优化策略。 展开更多
关键词 非期望产出 农业用水效率 节水潜力 sbm-undesirable模型 聚类分析
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Comparisons of Three-Dimensional Variational Data Assimilation and Model Output Statistics in Improving Atmospheric Chemistry Forecasts 被引量:1
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作者 Chaoqun MA Tijian WANG +1 位作者 Zengliang ZANG Zhijin LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第7期813-825,共13页
Atmospheric chemistry models usually perform badly in forecasting wintertime air pollution because of their uncertainties. Generally, such uncertainties can be decreased effectively by techniques such as data assimila... Atmospheric chemistry models usually perform badly in forecasting wintertime air pollution because of their uncertainties. Generally, such uncertainties can be decreased effectively by techniques such as data assimilation(DA) and model output statistics(MOS). However, the relative importance and combined effects of the two techniques have not been clarified. Here,a one-month air quality forecast with the Weather Research and Forecasting-Chemistry(WRF-Chem) model was carried out in a virtually operational setup focusing on Hebei Province, China. Meanwhile, three-dimensional variational(3 DVar) DA and MOS based on one-dimensional Kalman filtering were implemented separately and simultaneously to investigate their performance in improving the model forecast. Comparison with observations shows that the chemistry forecast with MOS outperforms that with 3 DVar DA, which could be seen in all the species tested over the whole 72 forecast hours. Combined use of both techniques does not guarantee a better forecast than MOS only, with the improvements and degradations being small and appearing rather randomly. Results indicate that the implementation of MOS is more suitable than 3 DVar DA in improving the operational forecasting ability of WRF-Chem. 展开更多
关键词 data assimilation model output statistics WRF-Chem operational forecast
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Credit Risk Model Taking Account of Inflation and Its Contribution to Macroeconomic Discussion on Effect of Inflation on Output Growth 被引量:2
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作者 Valery V.Shemetov 《Management Studies》 2020年第6期430-452,共23页
We use Extended Merton model(EMM)for estimating the firm’s credit risks in the presence of inflation.We show quantitatively that inflation is an influential factor making either a benign or adverse effect on the firm... We use Extended Merton model(EMM)for estimating the firm’s credit risks in the presence of inflation.We show quantitatively that inflation is an influential factor making either a benign or adverse effect on the firm’s survival,supporting at the microeconomic level New Keynesian findings of the nonlinear inflation effect on output growth.Lower inflation increasing the firm’s expected rate of return can raise its mean year returns and decrease its default probability.Higher inflation,decreasing the expected rate return,makes the opposite effect.The magnitude of the adverse effect depends on the firm strength:for a steady firm,this effect is small,whereas for a weaker firm,it can be fatal.EMM is the only model taking account of inflation.It can be useful for banks or insurance companies estimating credit risks of commercial borrowers over the debt maturity,and for the firm’s management planning long-term business operations. 展开更多
关键词 INFLATION corporate credit risks structural model non-linear inflation effect on output growth New Keynesian macroeconomics
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Iterative identification of output error model for industrial processes with time delay subject to colored noise 被引量:1
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作者 董世健 刘涛 +1 位作者 李明忠 曹毅 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期2005-2012,共8页
To deal with colored noise and unexpected load disturbance in identification of industrial processes with time delay, a bias-eliminated iterative least-squares(ILS) identification method is proposed in this paper to e... To deal with colored noise and unexpected load disturbance in identification of industrial processes with time delay, a bias-eliminated iterative least-squares(ILS) identification method is proposed in this paper to estimate the output error model parameters and time delay simultaneously. An extended observation vector is constructed to establish an ILS identification algorithm. Moreover, a variable forgetting factor is introduced to enhance the convergence rate of parameter estimation. For consistent estimation, an instrumental variable method is given to deal with the colored noise. The convergence and upper bound error of parameter estimation are analyzed. Two illustrative examples are used to show the effectiveness and merits of the proposed method. 展开更多
关键词 Time delay system output error model Recursive least-squares Instrumental variable Variable forgetting factor
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Output regulation of nonlinear singularly perturbed systems based on T-S fuzzy model
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作者 Shuwei CHEN 《控制理论与应用(英文版)》 EI 2005年第4期399-403,共5页
Based on the T-S model, the output regulation of nonlinear singularly perturbed systems via state feedback is discussed. It is shown that, under standard assumptions, this problean is solvable if and only if certain l... Based on the T-S model, the output regulation of nonlinear singularly perturbed systems via state feedback is discussed. It is shown that, under standard assumptions, this problean is solvable if and only if certain linear matrix equations are solvable. Once these equations are solvable, the state feedback regulator can easily be constructed. 展开更多
关键词 Nonlinear systems output regulation Singular perturbations Takagi-Sugeno fuzzy model
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Construction of Two-Region Input-output Model——A Case Study of Henan Province 被引量:1
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作者 SHANG Yong Department of Statistics, Henan University of Economics and Law, Zhengzhou 450002, China 《Asian Agricultural Research》 2012年第1期9-12,共4页
On the basis of input-output table of Henan Province and China in 2007, this paper advances a simple method of constructing two-region input-output model using MRIO model, to research the economic link between the ind... On the basis of input-output table of Henan Province and China in 2007, this paper advances a simple method of constructing two-region input-output model using MRIO model, to research the economic link between the industries of Henan Province and the industries of other regions. I summarize the characteristics of this method based on this as follows: when researching inter-regional economic link, the multi-region or two-region input-output model has prominent superiority, and we can conduct preliminary estimation on the multi-region input-output model using location quotient approach. 展开更多
关键词 INPUT-output model LOCATION QUOTIENT MRIO model In
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Environmental input-output model and its analysis with a focus on the solid waste management sectors
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作者 Zeng, Guang-Ming Yuan, Xing-Zhong +3 位作者 Zhang, Pan-Yue Guo, Huai-Cheng Huang, Gordon Guo-He Hemelaar, L. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第2期53-58,共6页
An environmental input output model (EIOM) was introduced to the regional solid waste management sectors, which can reflect the direct and indirect relations between the environment and the regional economy developme... An environmental input output model (EIOM) was introduced to the regional solid waste management sectors, which can reflect the direct and indirect relations between the environment and the regional economy development. Some details about how to use the EIOM was discussed. The EIOM was applied to the Changsha City in China. The example results indicate that much useful information related to the environment and the regional economy development can be gained from the solution of the EIOM. Thus, the EIOM can be used as a useful tool for the sustainable development planning including the solid waste management sectors. 展开更多
关键词 environmental input\|output model analysis of economy and environment solid waste management
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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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The Design of Output Feedback Distributed Model Predictive Controller for a Class of Nonlinear Systems
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作者 Baili Su Yingzhi Wang 《Applied Mathematics》 2017年第12期1832-1850,共19页
For a class of nonlinear systems whose states are immeasurable, when the outputs of the system are sampled asynchronously, by introducing a state observer, an output feedback distributed model predictive control algor... For a class of nonlinear systems whose states are immeasurable, when the outputs of the system are sampled asynchronously, by introducing a state observer, an output feedback distributed model predictive control algorithm is proposed. It is proved that the errors of estimated states and the actual system's states are bounded. And it is guaranteed that the estimated states of the closed-loop system are ultimately bounded in a region containing the origin. As a result, the states of the actual system are ultimately bounded. A simulation example verifies the effectiveness of the proposed distributed control method. 展开更多
关键词 Nonlinear Systems Distributed model PREDICTIVE Control State OBSERVER output Feedback ASYNCHRONOUS Measurements
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