With a focus on an industrial multivariable system, two subsystems including the flow and the level outputs are analysed and controlled, which have applicability in both real and academic environments. In such a case,...With a focus on an industrial multivariable system, two subsystems including the flow and the level outputs are analysed and controlled, which have applicability in both real and academic environments. In such a case, at first, each subsystem is distinctively represented by its model, since the outcomes point out that the chosen models have the same behavior as corresponding ones. Then, the industrial multivariable system and its presentation are achieved in line with the integration of these subsystems, since the interaction between them can not actually be ignored. To analyze the interaction presented, the Gershgorin bands need to be acquired, where the results are used to modify the system parameters to appropriate values. Subsequently, in the view of modeling results, the control concept in two different techniques including sequential loop closing control(SLCC) scheme and diagonal dominance control(DDC) schemes is proposed to implement on the system through the Profibus network, as long as the OPC(OLE for process control) server is utilized to communicate between the control schemes presented and the multivariable system. The real test scenarios are carried out and the corresponding outcomes in their present forms are acquired. In the same way, the proposed control schemes results are compared with each other, where the real consequences verify the validity of them in the field of the presented industrial multivariable system control.展开更多
Data-driven partial differential equation identification is a potential breakthrough to solve the lack of physical equations in complex dynamic systems.However,existing equation identification methods still cannot eff...Data-driven partial differential equation identification is a potential breakthrough to solve the lack of physical equations in complex dynamic systems.However,existing equation identification methods still cannot effectively identify equations from multivariable complex systems.In this work,we combine physical constraints such as dimension and direction of equation with data-driven method,and successfully identify the Navier-Stocks equations from the flow field data of Karman vortex street.This method provides an effective approach to identify partial differential equations of multivariable complex systems.展开更多
This paper considers the pole placement in multivariable systems involving known delays by using dynamic controllers subject to multirate sampling. The controller parameterizations are calculated from algebraic equati...This paper considers the pole placement in multivariable systems involving known delays by using dynamic controllers subject to multirate sampling. The controller parameterizations are calculated from algebraic equations which are solved by using the Kronecker product of matrices. It is pointed out that the sampling periods can be selected in a convenient way for the solvability of such equations under rather weak conditions provided that the continuous plant is spectrally controllable. Some overview about the use of nonuniform sampling is also given in order to improve the system's performance.展开更多
In order to solve the decoupling control problem of multivariable system with time delays,a new decoupling Smith control method for multivariable system with time delays was proposed. Firstly,the decoupler based on th...In order to solve the decoupling control problem of multivariable system with time delays,a new decoupling Smith control method for multivariable system with time delays was proposed. Firstly,the decoupler based on the adjoint matrix of the multivariable system model with time delays was introduced,and the decoupled models were reduced to first-order plus time delay models by analyzing the amplitude-frequency and phase-frequency characteristics. Secondly,according to the closed-loop characteristic equation of Smith predictor structure,proportion integration (PI) controllers were designed following the principle of pole assignment for Butterworth filter. Finally,using small-gain theorem and Nyquist stability criterion,sufficient and necessary conditions for robust stability were analyzed with multiplicative uncertainties,which could be encountered frequently in practice. The result shows that the method proposed has superiority for response speed and load disturbance rejection performance.展开更多
A new algorithm for constructing an inverse of a multivariable linear system is presented. This algorithm makes the constructing an inverse of the higher order matrices into searching for the equivalent normal form o...A new algorithm for constructing an inverse of a multivariable linear system is presented. This algorithm makes the constructing an inverse of the higher order matrices into searching for the equivalent normal form of the lower order matrices. Consequently, the calculation is more simple efficient and programmed than previous methods. Another result of the paper is that the lower reduced inverse system is obtained, by selecting special bases of the observable space of the original systems, it reveals the effect of the observability of the original systems on the order of the inverse systems.展开更多
To estimate atmospheric predictability for multivariable system, based on information theory in nonlinear error growth dynamics, a quantitative method is introduced in this paper using multivariable joint predictabili...To estimate atmospheric predictability for multivariable system, based on information theory in nonlinear error growth dynamics, a quantitative method is introduced in this paper using multivariable joint predictability limit(MJPL) and corresponding single variable predictability limit(SVPL). The predictability limit, obtained from the evolutions of nonlinear error entropy and climatological state entropy, is not only used to measure the predictability of dynamical system with the constant climatological state entropy, but also appropriate to the case of climatological state entropy changed with time. With the help of daily NCEP-NCAR reanalysis data, by using a method of local dynamical analog, the nonlinear error entropy, climatological state entropy, and predictability limit are obtained, and the SVPLs and MJPL of the winter 500-hPa temperature field, zonal wind field and meridional wind field are also investigated. The results show that atmospheric predictability is well associated with the analytical variable. For single variable predictability, there exists a big difference for the three variables, with the higher predictability found for the temperature field and zonal wind field and the lower predictability for the meridional wind field. As seen from their spatial distributions, the SVPLs of the three variables appear to have a property of zonal distribution, especially for the meridional wind field, which has three zonal belts with low predictability and four zonal belts with high predictability. For multivariable joint predictability, the MJPL of multivariable system with the three variables is not a simple mean or linear combination of its SVPLs. It presents an obvious regional difference characteristic. Different regions have different results. In some regions, the MJPL is among its SVPLs. However, in other regions, the MJPL is less than its all SVPLs.展开更多
In the present paper, the formulae for matrix Padé-type approximation were improved. The mixed model reduction method of matrix Padé-type-Routh for the multivariable linear systems was presented. A well-know...In the present paper, the formulae for matrix Padé-type approximation were improved. The mixed model reduction method of matrix Padé-type-Routh for the multivariable linear systems was presented. A well-known example was given to illustrate that the mixed method is efficient.展开更多
The objective of this paper is to develop a variable learning rate for neural modeling of multivariable nonlinear stochastic system. The corresponding parameter is obtained by gradient descent method optimization. The...The objective of this paper is to develop a variable learning rate for neural modeling of multivariable nonlinear stochastic system. The corresponding parameter is obtained by gradient descent method optimization. The effectiveness of the suggested algorithm applied to the identification of behavior of two nonlinear stochastic systems is demonstrated by simulation experiments.展开更多
In this paper, multimodel and neural emulators are proposed for uncoupled multivariable nonlinear plants with unknown dynamics. The contributions of this paper are to extend the emulators to multivariable non square s...In this paper, multimodel and neural emulators are proposed for uncoupled multivariable nonlinear plants with unknown dynamics. The contributions of this paper are to extend the emulators to multivariable non square systems and to propose a systematic method to compute the multimodel synthesis parameters. The effectiveness of the proposed emulators is shown through two simulation examples. The obtained results are very satisfactory, they illustrate the performance of both emulators and show the advantages of the multimodel emulator relatively to the neural one.展开更多
Traditional centralized Proportional Integral(PI)controller design methods based on Equivalent Transfer Functions(ETFs)have poor decoupling effect in turboprop engines.In this paper,a centralized PI design method base...Traditional centralized Proportional Integral(PI)controller design methods based on Equivalent Transfer Functions(ETFs)have poor decoupling effect in turboprop engines.In this paper,a centralized PI design method based on dynamic imaginary matrix and equivalent transfer function is proposed.Firstly,a method for solving equivalent transfer functions based on the dynamic imaginary matrix is proposed,which adopts dynamic imaginary matrix to describe the dynamic characteristics of the system,and obtains the equivalent transfer function based on the dynamic imaginary matrix characteristics.Secondly,for the equivalent transfer function,a central-ized PI control gain is designed using the Taylor expansion method.Meanwhile,this paper further proves that the centralized PI design method proposed in this paper has integral stability.Consid-ering the impact of altitude and Mach number on turboprop engines,a linear feedforward control method based on the transfer function matrix is further proposed based on the centralized PI con-troller,and the stability of the entire comprehensive control method is proved.Finally,to ensure the safe and effective operation of the turboprop engine,a temperature and torque limiting protection controller is designed for the turboprop engine.Simulation results show that the centralized PI con-troller design method and linear feedforward control method proposed can effectively improve the control quality of turboprop engine control systems.展开更多
A discrete-dine control system model of equipment spare parts is proposed In this model,the stochastic demand, of the spare parts is described by the state equation disturbance. The controlpolicy of the system was ded...A discrete-dine control system model of equipment spare parts is proposed In this model,the stochastic demand, of the spare parts is described by the state equation disturbance. The controlpolicy of the system was deduced by means of the methods of a multivariable self-tuning regulatorand reduced-cud r state observer. An example was given in the end.展开更多
In this article,the dynamical model and trajectory tracking problem for a tilt-rotor unmanned aerial vehicle is tackled through linear Active Disturbance Rejection Control(ADRC)applied on the tangent linearized system...In this article,the dynamical model and trajectory tracking problem for a tilt-rotor unmanned aerial vehicle is tackled through linear Active Disturbance Rejection Control(ADRC)applied on the tangent linearized system.To apply the ADRC scheme,it is considered the subsystem without the Y-axis component,which is differentially flat and whose flat outputs are obtained using the Kronecker matrix.Numerical assessment using as system parameters the ones of a scale prototype is provided to show the effectiveness of the proposal leading to accurate tracking results using admissible control values for an experimental scenario.展开更多
This paper presents in organized form a number of results that have appeared in the literature in the last two decades,concerning the design of control laws for multi-input multi-output nonlinear systems,with emphasis...This paper presents in organized form a number of results that have appeared in the literature in the last two decades,concerning the design of control laws for multi-input multi-output nonlinear systems,with emphasis on the problem of stabilizing an equilibrium,and addresses,at a broad level generality,systems that are invertible from an input-output viewpoint.展开更多
A constrained decoupling (generalized predictive control) GPC algorithm is proposed for MIMO (malti-input multi-output) system. This algorithm takes account of all constraints of inputs and their increments. By solvin...A constrained decoupling (generalized predictive control) GPC algorithm is proposed for MIMO (malti-input multi-output) system. This algorithm takes account of all constraints of inputs and their increments. By solving matrix equations, the multi-step predictive decoupling controllers are realized. This algorithm need not solve Diophantine functions, and weakens the cross-coupling of the variables. At last the simulation results demon- strate the effectiveness of this proposed strategy.展开更多
In order to estimate the reliability of wind turbine gearbox based on the system level, a generalized stress-strength model is introduced. Considering that the system works properly under a variety of random stresses ...In order to estimate the reliability of wind turbine gearbox based on the system level, a generalized stress-strength model is introduced. Considering that the system works properly under a variety of random stresses which affect every component, the total stress on the system is given by a known linear combination of the stresses of all components. Then the strength of the system can be viewed as a linear combination of the strengths of relative components. In this model, stress and strength are independent of each other. Reliability of the system is the probability that strength exceeds stress. Finally, the reliability of wind turbine gearbox is estimated by the multivariable reliability calculation method. The corresponding result is compared with the results of reliability in the extreme cases(completely dependent and completely independent) by the traditional evaluation method.展开更多
Through modifying the CPN model, a kind of multivariable fuzzy model is put forward, and the matching fuzzy multistep predictive control algorithm is deduced based on the model. The modified model works in a competiti...Through modifying the CPN model, a kind of multivariable fuzzy model is put forward, and the matching fuzzy multistep predictive control algorithm is deduced based on the model. The modified model works in a competitive output manner which results in its local representation property. While studying on line, only a few parameters need to be regulated. So the model has the merits of fast learning and on line self organizing modeling. The control algorithm is simple, adaptive and useful in multivariable and time delay systems. Applying the algorithm in a paper making system, simulation shows its good effect.展开更多
For a stochastic non-minimum phase multivariable system,a multiple models direct adaptive controller is presented.It is composed of multiple fixed models with two adaptive models.The fixed models are used to cover the...For a stochastic non-minimum phase multivariable system,a multiple models direct adaptive controller is presented.It is composed of multiple fixed models with two adaptive models.The fixed models are used to cover the region where the system parameters jump and improve the transient response,while another two adaptive models are used to guarantee the stability.Utilizing generalized minimum variance design method,it adopts the stochastic system estimation algorithm with optimal controller design method to identify the controller parameter directly.Finally,the global convergence is given.The simulation proves the effectives of the controller proposed.展开更多
The One Health concept acknowledges the importance of multiple dimensions in controlling antimicrobial resistance(AMR).However,our understanding of how anthropological,socioeconomic,and environmental factors drive AMR...The One Health concept acknowledges the importance of multiple dimensions in controlling antimicrobial resistance(AMR).However,our understanding of how anthropological,socioeconomic,and environmental factors drive AMR at a national level remains limited.To explore associations between potential contributing factors and AMR,this study analyzed an extensive database comprising 13 major antibioticresistant bacteria and over 30 predictors(e.g.,air pollution,antibiotic usage,economy,husbandry,public services,health services,education,diet,climate,and population)from 2014 to 2020 across China.The multivariate analysis results indicate that fine particulate matter with a diameter of 2.5 μm or less(PM_(2.5))is associated with AMR,accounting for 12%of the variation,followed by residents’income(10.3%)and antibiotic usage density(5.1%).A reduction in PM_(2.5)of 1 μg·m^(-3)is linked to a 0.17%decrease in aggregate antibiotic resistance(p<0.001,R^(2)=0.74).Under different scenarios of China’s PM_(2.5)airquality projections,we further estimated the premature death toll and economic burden derived from PM_(2.5)-related antibiotic resistance in China until 2060.PM_(2.5)-derived AMR is estimated to cause approximately 27000(95%confidence interval(CI):646848830)premature deaths and about 0.51(95%CI;0.12-0.92)million years of life lost annually in China,equivalent to an annual welfare loss of 8.4(95%CI;2.0-15.0)billion USD.Implementing the“Ambitious Pollution 1.5℃ Goals”scenario to reduce PM_(2.5)concentrations could prevent roughly 14000(95%CI;3324-26320)premature deaths—with a potential monetary value of 9.8(95%CI;2.2-17.6)billion USD—from AMR by 2060.These results suggest that reducing air pollution may offer co-benefits in the health and economic sectors by mitigating AMR.展开更多
The invertible of the Large Air Dense Medium Fluidized Bed (ADMFB) were studied by introducing the concept of the inverse system theory of nonlinear systems. Then the ADMFB, which was a multivariable, nonlinear and co...The invertible of the Large Air Dense Medium Fluidized Bed (ADMFB) were studied by introducing the concept of the inverse system theory of nonlinear systems. Then the ADMFB, which was a multivariable, nonlinear and coupled strongly system, was decoupled into independent SISO pseudo-linear subsystems. Linear controllers were designed for each of subsystems based on linear systems theory. The practice output proves that this method improves the stability of the ADMFB obviously.展开更多
文摘With a focus on an industrial multivariable system, two subsystems including the flow and the level outputs are analysed and controlled, which have applicability in both real and academic environments. In such a case, at first, each subsystem is distinctively represented by its model, since the outcomes point out that the chosen models have the same behavior as corresponding ones. Then, the industrial multivariable system and its presentation are achieved in line with the integration of these subsystems, since the interaction between them can not actually be ignored. To analyze the interaction presented, the Gershgorin bands need to be acquired, where the results are used to modify the system parameters to appropriate values. Subsequently, in the view of modeling results, the control concept in two different techniques including sequential loop closing control(SLCC) scheme and diagonal dominance control(DDC) schemes is proposed to implement on the system through the Profibus network, as long as the OPC(OLE for process control) server is utilized to communicate between the control schemes presented and the multivariable system. The real test scenarios are carried out and the corresponding outcomes in their present forms are acquired. In the same way, the proposed control schemes results are compared with each other, where the real consequences verify the validity of them in the field of the presented industrial multivariable system control.
基金supported by the National Natural Science Foundation of China(No.92152301).
文摘Data-driven partial differential equation identification is a potential breakthrough to solve the lack of physical equations in complex dynamic systems.However,existing equation identification methods still cannot effectively identify equations from multivariable complex systems.In this work,we combine physical constraints such as dimension and direction of equation with data-driven method,and successfully identify the Navier-Stocks equations from the flow field data of Karman vortex street.This method provides an effective approach to identify partial differential equations of multivariable complex systems.
文摘This paper considers the pole placement in multivariable systems involving known delays by using dynamic controllers subject to multirate sampling. The controller parameterizations are calculated from algebraic equations which are solved by using the Kronecker product of matrices. It is pointed out that the sampling periods can be selected in a convenient way for the solvability of such equations under rather weak conditions provided that the continuous plant is spectrally controllable. Some overview about the use of nonuniform sampling is also given in order to improve the system's performance.
基金Projects(60634020, 61074117) supported by the National Natural Science Foundation of China
文摘In order to solve the decoupling control problem of multivariable system with time delays,a new decoupling Smith control method for multivariable system with time delays was proposed. Firstly,the decoupler based on the adjoint matrix of the multivariable system model with time delays was introduced,and the decoupled models were reduced to first-order plus time delay models by analyzing the amplitude-frequency and phase-frequency characteristics. Secondly,according to the closed-loop characteristic equation of Smith predictor structure,proportion integration (PI) controllers were designed following the principle of pole assignment for Butterworth filter. Finally,using small-gain theorem and Nyquist stability criterion,sufficient and necessary conditions for robust stability were analyzed with multiplicative uncertainties,which could be encountered frequently in practice. The result shows that the method proposed has superiority for response speed and load disturbance rejection performance.
文摘A new algorithm for constructing an inverse of a multivariable linear system is presented. This algorithm makes the constructing an inverse of the higher order matrices into searching for the equivalent normal form of the lower order matrices. Consequently, the calculation is more simple efficient and programmed than previous methods. Another result of the paper is that the lower reduced inverse system is obtained, by selecting special bases of the observable space of the original systems, it reveals the effect of the observability of the original systems on the order of the inverse systems.
基金supported by the National Natural Science Foundation of China (Grant No. 41375063)
文摘To estimate atmospheric predictability for multivariable system, based on information theory in nonlinear error growth dynamics, a quantitative method is introduced in this paper using multivariable joint predictability limit(MJPL) and corresponding single variable predictability limit(SVPL). The predictability limit, obtained from the evolutions of nonlinear error entropy and climatological state entropy, is not only used to measure the predictability of dynamical system with the constant climatological state entropy, but also appropriate to the case of climatological state entropy changed with time. With the help of daily NCEP-NCAR reanalysis data, by using a method of local dynamical analog, the nonlinear error entropy, climatological state entropy, and predictability limit are obtained, and the SVPLs and MJPL of the winter 500-hPa temperature field, zonal wind field and meridional wind field are also investigated. The results show that atmospheric predictability is well associated with the analytical variable. For single variable predictability, there exists a big difference for the three variables, with the higher predictability found for the temperature field and zonal wind field and the lower predictability for the meridional wind field. As seen from their spatial distributions, the SVPLs of the three variables appear to have a property of zonal distribution, especially for the meridional wind field, which has three zonal belts with low predictability and four zonal belts with high predictability. For multivariable joint predictability, the MJPL of multivariable system with the three variables is not a simple mean or linear combination of its SVPLs. It presents an obvious regional difference characteristic. Different regions have different results. In some regions, the MJPL is among its SVPLs. However, in other regions, the MJPL is less than its all SVPLs.
基金Project supported by National Natural Science Foundation of China (Grant No .10271074)
文摘In the present paper, the formulae for matrix Padé-type approximation were improved. The mixed model reduction method of matrix Padé-type-Routh for the multivariable linear systems was presented. A well-known example was given to illustrate that the mixed method is efficient.
文摘The objective of this paper is to develop a variable learning rate for neural modeling of multivariable nonlinear stochastic system. The corresponding parameter is obtained by gradient descent method optimization. The effectiveness of the suggested algorithm applied to the identification of behavior of two nonlinear stochastic systems is demonstrated by simulation experiments.
文摘In this paper, multimodel and neural emulators are proposed for uncoupled multivariable nonlinear plants with unknown dynamics. The contributions of this paper are to extend the emulators to multivariable non square systems and to propose a systematic method to compute the multimodel synthesis parameters. The effectiveness of the proposed emulators is shown through two simulation examples. The obtained results are very satisfactory, they illustrate the performance of both emulators and show the advantages of the multimodel emulator relatively to the neural one.
基金support by the National Natural Science Foundation of China (No.52202474)China Postdoctoral Science Foundation (No.2023M731655)+3 种基金Major Projects of National Science and Technology,China (No.J2019-I-0020-0019)Advanced Aviation Power Innovation Workstation Project,China (No.HKCX2022-01-026-03)Basic Research Business Fees for Central Universities,China (No.NT2023004)Nanjing University of Aeronautics and Astronautics Forward-looking Layout Research Project,China (No.1002-ILA22037-1A22).
文摘Traditional centralized Proportional Integral(PI)controller design methods based on Equivalent Transfer Functions(ETFs)have poor decoupling effect in turboprop engines.In this paper,a centralized PI design method based on dynamic imaginary matrix and equivalent transfer function is proposed.Firstly,a method for solving equivalent transfer functions based on the dynamic imaginary matrix is proposed,which adopts dynamic imaginary matrix to describe the dynamic characteristics of the system,and obtains the equivalent transfer function based on the dynamic imaginary matrix characteristics.Secondly,for the equivalent transfer function,a central-ized PI control gain is designed using the Taylor expansion method.Meanwhile,this paper further proves that the centralized PI design method proposed in this paper has integral stability.Consid-ering the impact of altitude and Mach number on turboprop engines,a linear feedforward control method based on the transfer function matrix is further proposed based on the centralized PI con-troller,and the stability of the entire comprehensive control method is proved.Finally,to ensure the safe and effective operation of the turboprop engine,a temperature and torque limiting protection controller is designed for the turboprop engine.Simulation results show that the centralized PI con-troller design method and linear feedforward control method proposed can effectively improve the control quality of turboprop engine control systems.
文摘A discrete-dine control system model of equipment spare parts is proposed In this model,the stochastic demand, of the spare parts is described by the state equation disturbance. The controlpolicy of the system was deduced by means of the methods of a multivariable self-tuning regulatorand reduced-cud r state observer. An example was given in the end.
基金supported by the Secretaría de Investigación y Posgrado del Instituto Politécnico Nacional(SIP-IPN)under grants 20250098,20250168,20251291 and 20254791by Universidad Iberoamericana Ciudad de México+1 种基金Victor G.Sánchez-Meza is a Secretaría de Ciencia,Humanidades,Tecnología e Innovación(Secihti)fellow(CVU 964590)support received.Yair Lozano thanks the support of the Coordinación de Operación y Redes de Investigación y Posgrado of the IPN through the Red de Inteligencia Artificial y Ciencia de Datos and the Red de Expertos en Innovación Automotriz.
文摘In this article,the dynamical model and trajectory tracking problem for a tilt-rotor unmanned aerial vehicle is tackled through linear Active Disturbance Rejection Control(ADRC)applied on the tangent linearized system.To apply the ADRC scheme,it is considered the subsystem without the Y-axis component,which is differentially flat and whose flat outputs are obtained using the Kronecker matrix.Numerical assessment using as system parameters the ones of a scale prototype is provided to show the effectiveness of the proposal leading to accurate tracking results using admissible control values for an experimental scenario.
文摘This paper presents in organized form a number of results that have appeared in the literature in the last two decades,concerning the design of control laws for multi-input multi-output nonlinear systems,with emphasis on the problem of stabilizing an equilibrium,and addresses,at a broad level generality,systems that are invertible from an input-output viewpoint.
基金Supported by the National Natural Science Foundation of China (No.60374037, No.60574036), the Program for New Century Excellent Talents in University of China (NCET), and the Specialized Research Fund for the Doctoral Program of Higher Edu-cation of China (No.20050055013).
文摘A constrained decoupling (generalized predictive control) GPC algorithm is proposed for MIMO (malti-input multi-output) system. This algorithm takes account of all constraints of inputs and their increments. By solving matrix equations, the multi-step predictive decoupling controllers are realized. This algorithm need not solve Diophantine functions, and weakens the cross-coupling of the variables. At last the simulation results demon- strate the effectiveness of this proposed strategy.
基金the National Natural Science Foundation of China(No.51265025)
文摘In order to estimate the reliability of wind turbine gearbox based on the system level, a generalized stress-strength model is introduced. Considering that the system works properly under a variety of random stresses which affect every component, the total stress on the system is given by a known linear combination of the stresses of all components. Then the strength of the system can be viewed as a linear combination of the strengths of relative components. In this model, stress and strength are independent of each other. Reliability of the system is the probability that strength exceeds stress. Finally, the reliability of wind turbine gearbox is estimated by the multivariable reliability calculation method. The corresponding result is compared with the results of reliability in the extreme cases(completely dependent and completely independent) by the traditional evaluation method.
文摘Through modifying the CPN model, a kind of multivariable fuzzy model is put forward, and the matching fuzzy multistep predictive control algorithm is deduced based on the model. The modified model works in a competitive output manner which results in its local representation property. While studying on line, only a few parameters need to be regulated. So the model has the merits of fast learning and on line self organizing modeling. The control algorithm is simple, adaptive and useful in multivariable and time delay systems. Applying the algorithm in a paper making system, simulation shows its good effect.
基金the National Natural Science Foundation of China (Nos.60504010 and 60774015)the National High Technology Research and Development Program (863) of China (No.2008AA04Z129)+1 种基金the Disbursal Budget Program of Shanghai Municipal Education Commission of China (No.2008093) the Innovation Program of Shanghai Municipal Education Commission of China (No.09YZ241)
文摘For a stochastic non-minimum phase multivariable system,a multiple models direct adaptive controller is presented.It is composed of multiple fixed models with two adaptive models.The fixed models are used to cover the region where the system parameters jump and improve the transient response,while another two adaptive models are used to guarantee the stability.Utilizing generalized minimum variance design method,it adopts the stochastic system estimation algorithm with optimal controller design method to identify the controller parameter directly.Finally,the global convergence is given.The simulation proves the effectives of the controller proposed.
基金funded by the National Natural Science Foun-dation of China(22406168,W2411031,and 52270201)the China Postdoctoral Science Foundation(2023M733061)the Zhejiang University Global Partnership Fund(100000-11320/198).
文摘The One Health concept acknowledges the importance of multiple dimensions in controlling antimicrobial resistance(AMR).However,our understanding of how anthropological,socioeconomic,and environmental factors drive AMR at a national level remains limited.To explore associations between potential contributing factors and AMR,this study analyzed an extensive database comprising 13 major antibioticresistant bacteria and over 30 predictors(e.g.,air pollution,antibiotic usage,economy,husbandry,public services,health services,education,diet,climate,and population)from 2014 to 2020 across China.The multivariate analysis results indicate that fine particulate matter with a diameter of 2.5 μm or less(PM_(2.5))is associated with AMR,accounting for 12%of the variation,followed by residents’income(10.3%)and antibiotic usage density(5.1%).A reduction in PM_(2.5)of 1 μg·m^(-3)is linked to a 0.17%decrease in aggregate antibiotic resistance(p<0.001,R^(2)=0.74).Under different scenarios of China’s PM_(2.5)airquality projections,we further estimated the premature death toll and economic burden derived from PM_(2.5)-related antibiotic resistance in China until 2060.PM_(2.5)-derived AMR is estimated to cause approximately 27000(95%confidence interval(CI):646848830)premature deaths and about 0.51(95%CI;0.12-0.92)million years of life lost annually in China,equivalent to an annual welfare loss of 8.4(95%CI;2.0-15.0)billion USD.Implementing the“Ambitious Pollution 1.5℃ Goals”scenario to reduce PM_(2.5)concentrations could prevent roughly 14000(95%CI;3324-26320)premature deaths—with a potential monetary value of 9.8(95%CI;2.2-17.6)billion USD—from AMR by 2060.These results suggest that reducing air pollution may offer co-benefits in the health and economic sectors by mitigating AMR.
文摘The invertible of the Large Air Dense Medium Fluidized Bed (ADMFB) were studied by introducing the concept of the inverse system theory of nonlinear systems. Then the ADMFB, which was a multivariable, nonlinear and coupled strongly system, was decoupled into independent SISO pseudo-linear subsystems. Linear controllers were designed for each of subsystems based on linear systems theory. The practice output proves that this method improves the stability of the ADMFB obviously.
