In this paper,a multi-loop internal model control(IMC) scheme in conjunction with feed-forward strategy based on the dynamic partial least squares(DyPLS) framework is proposed.Unlike the traditional methods to decoupl...In this paper,a multi-loop internal model control(IMC) scheme in conjunction with feed-forward strategy based on the dynamic partial least squares(DyPLS) framework is proposed.Unlike the traditional methods to decouple multi-input multi-output(MIMO) systems,the DyPLS framework automatically decomposes the MIMO process into a multi-loop system in the PLS subspace in the modeling stage.The dynamic filters with identical structure are used to build the dynamic PLS model,which retains the orthogonality among the latent variables.To address the model mismatch problem,an off-line least squares method is applied to obtain a set of optimal filter parameters in each latent space.Without losing the merits of model-based control,a simple and easy-tuned IMC structure is readily carried over to the dynamic PLS control framework.In addition,by projecting the measurable disturbance into the latent subspace,a multi-loop feed-forward control is yielded to achieve better performance for disturbance rejection.Simulation results of a distillation column are used to further demonstrate this new strategy outperforms conventional control schemes in servo behavior and disturbance rejection.展开更多
A multi-loop constrained model predictive control scheme based on autoregressive exogenous-partial least squares(ARX-PLS) framework is proposed to tackle the high dimension, coupled and constraints problems in industr...A multi-loop constrained model predictive control scheme based on autoregressive exogenous-partial least squares(ARX-PLS) framework is proposed to tackle the high dimension, coupled and constraints problems in industry processes due to safety limitation, environmental regulations, consumer specifications and physical restriction. ARX-PLS decoupling character enables to turn the multivariable model predictive control(MPC) controller design in original space into the multi-loop single input single output(SISO) MPC controllers design in latent space.An idea of iterative method is applied to decouple the constraints latent variables in PLS framework and recursive least square is introduced to identify ARX-PLS model. This algorithm is applied to a non-square simulation system and a stirred reactor for ethylene polymerizations comparing with adaptive internal model control(IMC) method based on ARX-PLS framework. Its application has shown that this method outperforms adaptive IMC method based on ARX-PLS framework to some extent.展开更多
Circadian clocks are comprised of self-sustained transcriptional/translational feedback loops, which regulate the rhythms of physiology and behavior in mammals. CLOCK-interacting protein, Circadian(CIPC), has been ind...Circadian clocks are comprised of self-sustained transcriptional/translational feedback loops, which regulate the rhythms of physiology and behavior in mammals. CLOCK-interacting protein, Circadian(CIPC), has been indicated as an additional negative-feedback regulator of the circadian clock in vitro, although its physiological roles in circadian clock are unknown. Here, we generated Cipc homozygous knockout(Cipc-/-) mice and assessed the resultant circadian phenotypes. Surprisingly, the m RNA expression profiles of core clock genes in the liver of Cipc-/- mice showed no significant differences from that in wild-type mice except for Per1. Cipc-/- mice displayed normal locomotor rhythm and entrained activity pattern in both 12:12 light-dark cycle and constant dark cycle. Furthermore, deletion of Cipc in lungs and adipose tissues did not influence their peripheral clock. The results from this work provided more conclusive data suggesting that CIPC is not critically required for basic clock function.展开更多
基金Supported by the National Natural Science Foundation of China（60574047） the National High Technology Research and Development Program of China（2007AA04Z168 2009AA04Z154） the Research Fund for the Doctoral Program of Higher Education in China（20050335018）
文摘In this paper,a multi-loop internal model control(IMC) scheme in conjunction with feed-forward strategy based on the dynamic partial least squares(DyPLS) framework is proposed.Unlike the traditional methods to decouple multi-input multi-output(MIMO) systems,the DyPLS framework automatically decomposes the MIMO process into a multi-loop system in the PLS subspace in the modeling stage.The dynamic filters with identical structure are used to build the dynamic PLS model,which retains the orthogonality among the latent variables.To address the model mismatch problem,an off-line least squares method is applied to obtain a set of optimal filter parameters in each latent space.Without losing the merits of model-based control,a simple and easy-tuned IMC structure is readily carried over to the dynamic PLS control framework.In addition,by projecting the measurable disturbance into the latent subspace,a multi-loop feed-forward control is yielded to achieve better performance for disturbance rejection.Simulation results of a distillation column are used to further demonstrate this new strategy outperforms conventional control schemes in servo behavior and disturbance rejection.
基金Supported by the National Natural Science Foundation of China （61174114, 60574047）, the National High Technology Re-search and Development Program of China （2007AA04Z168） and the Research Fund for the Doctoral Program of Higher Education of China （20120101130016）.
文摘A multi-loop constrained model predictive control scheme based on autoregressive exogenous-partial least squares(ARX-PLS) framework is proposed to tackle the high dimension, coupled and constraints problems in industry processes due to safety limitation, environmental regulations, consumer specifications and physical restriction. ARX-PLS decoupling character enables to turn the multivariable model predictive control(MPC) controller design in original space into the multi-loop single input single output(SISO) MPC controllers design in latent space.An idea of iterative method is applied to decouple the constraints latent variables in PLS framework and recursive least square is introduced to identify ARX-PLS model. This algorithm is applied to a non-square simulation system and a stirred reactor for ethylene polymerizations comparing with adaptive internal model control(IMC) method based on ARX-PLS framework. Its application has shown that this method outperforms adaptive IMC method based on ARX-PLS framework to some extent.
基金supported by the National Natural Science Foundation of China(31171343 and 31230049 to Xu Ying)Ministry of Science and Technology(2006BAI23B00 to Xu Ying and Gao Xiang)
文摘Circadian clocks are comprised of self-sustained transcriptional/translational feedback loops, which regulate the rhythms of physiology and behavior in mammals. CLOCK-interacting protein, Circadian(CIPC), has been indicated as an additional negative-feedback regulator of the circadian clock in vitro, although its physiological roles in circadian clock are unknown. Here, we generated Cipc homozygous knockout(Cipc-/-) mice and assessed the resultant circadian phenotypes. Surprisingly, the m RNA expression profiles of core clock genes in the liver of Cipc-/- mice showed no significant differences from that in wild-type mice except for Per1. Cipc-/- mice displayed normal locomotor rhythm and entrained activity pattern in both 12:12 light-dark cycle and constant dark cycle. Furthermore, deletion of Cipc in lungs and adipose tissues did not influence their peripheral clock. The results from this work provided more conclusive data suggesting that CIPC is not critically required for basic clock function.
