In the paper, an iterative method is presented to the optimal control of batch processes. Generally it is very difficult to acquire an accurate mechanistic model for a batch process. Because support vector machine is ...In the paper, an iterative method is presented to the optimal control of batch processes. Generally it is very difficult to acquire an accurate mechanistic model for a batch process. Because support vector machine is powerful for the problems characterized by small samples, nonlinearity, high dimension and local minima, support vector regression models are developed for the optimal control of batch processes where end-point properties are required. The model parameters are selected within the Bayesian evidence framework. Based on the model, an iterative method is used to exploit the repetitive nature of batch processes to determine the optimal operating policy. Numerical simulation shows that the iterative optimal control can improve the process performance through iterations.展开更多
The traditional least squares support vector regression(LS-SVR)model,using cross validation to determine the regularization parameter and kernel parameter,is time-consuming.We propose a Bayesian evidence framework t...The traditional least squares support vector regression(LS-SVR)model,using cross validation to determine the regularization parameter and kernel parameter,is time-consuming.We propose a Bayesian evidence framework to infer the LS-SVR model parameters.Three levels Bayesian inferences are used to determine the model parameters,regularization hyper-parameters and tune the nuclear parameters by model comparison.On this basis,we established Bayesian LS-SVR time-series gas forecasting models and provide steps for the algorithm.The gas outburst data of a Hebi 10th mine working face is used to validate the model.The optimal embedding dimension and delay time of the time series were obtained by the smallest differential entropy method.Finally,within a MATLAB7.1 environment,we used actual coal gas data to compare the traditional LS-SVR and the Bayesian LS-SVR with LS-SVMlab1.5 Toolbox simulation.The results show that the Bayesian framework of an LS-SVR significantly improves the speed and accuracy of the forecast.展开更多
There are many structural lateral systems used in tall buildings: rigid frames, braced frames, shear walls, tubular structures and core structures. The outrigger and belt truss systems are efficient structures for dr...There are many structural lateral systems used in tall buildings: rigid frames, braced frames, shear walls, tubular structures and core structures. The outrigger and belt truss systems are efficient structures for drift control and base moment reduction in tall buildings where the core alone is not rigid enough to resist lateral loads. Perimeter columns are mobilized for increasing the effective width of the structure, and they developed tension in the windward columns and compression in the leeward columns. Optimum locations for the outriggers have been studied because of the influence on the top displacement and base moment in the core. It was analyzed the optimal position for two to seven outriggers and belt trusses, aiming to achieve minimum bending moment and minimum drift.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.60504033)
文摘In the paper, an iterative method is presented to the optimal control of batch processes. Generally it is very difficult to acquire an accurate mechanistic model for a batch process. Because support vector machine is powerful for the problems characterized by small samples, nonlinearity, high dimension and local minima, support vector regression models are developed for the optimal control of batch processes where end-point properties are required. The model parameters are selected within the Bayesian evidence framework. Based on the model, an iterative method is used to exploit the repetitive nature of batch processes to determine the optimal operating policy. Numerical simulation shows that the iterative optimal control can improve the process performance through iterations.
基金Financial support for this work,provided by the National Natural Science Foundation of China(No.60974126)the Natural Science Foundation of Jiangsu Province(No.BK2009094)
文摘The traditional least squares support vector regression(LS-SVR)model,using cross validation to determine the regularization parameter and kernel parameter,is time-consuming.We propose a Bayesian evidence framework to infer the LS-SVR model parameters.Three levels Bayesian inferences are used to determine the model parameters,regularization hyper-parameters and tune the nuclear parameters by model comparison.On this basis,we established Bayesian LS-SVR time-series gas forecasting models and provide steps for the algorithm.The gas outburst data of a Hebi 10th mine working face is used to validate the model.The optimal embedding dimension and delay time of the time series were obtained by the smallest differential entropy method.Finally,within a MATLAB7.1 environment,we used actual coal gas data to compare the traditional LS-SVR and the Bayesian LS-SVR with LS-SVMlab1.5 Toolbox simulation.The results show that the Bayesian framework of an LS-SVR significantly improves the speed and accuracy of the forecast.
文摘There are many structural lateral systems used in tall buildings: rigid frames, braced frames, shear walls, tubular structures and core structures. The outrigger and belt truss systems are efficient structures for drift control and base moment reduction in tall buildings where the core alone is not rigid enough to resist lateral loads. Perimeter columns are mobilized for increasing the effective width of the structure, and they developed tension in the windward columns and compression in the leeward columns. Optimum locations for the outriggers have been studied because of the influence on the top displacement and base moment in the core. It was analyzed the optimal position for two to seven outriggers and belt trusses, aiming to achieve minimum bending moment and minimum drift.