Tubular flow reactors are mainly used in chemical industry and waste water discharged units. Control of output variables is very difficult because of the existence of high dead-time in these types of reactors. In the ...Tubular flow reactors are mainly used in chemical industry and waste water discharged units. Control of output variables is very difficult because of the existence of high dead-time in these types of reactors. In the present work, sodium hydroxide and acetic acid solutions were sent to the tubular flow reactor. The aim was to control p H at 7 in the nonlinear region. The p H control of a tubular flow reactor with high time delay and a highly nonlinear behavior in p H neutralization reaction was investigated experimentally in the face of the various load and set point changes. Firstly, efficiency of conventional Proportional-Integral-Derivative(PID) algorithm in the experiments was tested. Then self-tuning PID(STPID) control system was applied by using the ARMAX model. The model parameters were calculated from input–output data by using PRBS signal as disturbance and Bierman algorithm. Lastly, the experimental fuzzy control of p H based on fuzzy model was achieved to compare the success of fuzzy approach with the performance of other control cases studied.展开更多
Absolute integrability and its absolute value inequality for fuzzy-number-valued func- tions are worth to be considered.In this paper,absolute integrability and its absolute value inequality for fuzzy-number-valued fu...Absolute integrability and its absolute value inequality for fuzzy-number-valued func- tions are worth to be considered.In this paper,absolute integrability and its absolute value inequality for fuzzy-number-valued functions are discussed by means of the characteristic the- orems of nonabsolute fuzzy integrals and the embedding theorem,i.e.,the fuzzy number space can be embedded into a concrete Banach space.Several necessary and sufficient conditions and examples are given.展开更多
文摘Tubular flow reactors are mainly used in chemical industry and waste water discharged units. Control of output variables is very difficult because of the existence of high dead-time in these types of reactors. In the present work, sodium hydroxide and acetic acid solutions were sent to the tubular flow reactor. The aim was to control p H at 7 in the nonlinear region. The p H control of a tubular flow reactor with high time delay and a highly nonlinear behavior in p H neutralization reaction was investigated experimentally in the face of the various load and set point changes. Firstly, efficiency of conventional Proportional-Integral-Derivative(PID) algorithm in the experiments was tested. Then self-tuning PID(STPID) control system was applied by using the ARMAX model. The model parameters were calculated from input–output data by using PRBS signal as disturbance and Bierman algorithm. Lastly, the experimental fuzzy control of p H based on fuzzy model was achieved to compare the success of fuzzy approach with the performance of other control cases studied.
基金the National Natural Science Foundation of China （No. 10771171） the Scientific Research Item of Gansu Education Department （No. 0601-20）.
文摘Absolute integrability and its absolute value inequality for fuzzy-number-valued func- tions are worth to be considered.In this paper,absolute integrability and its absolute value inequality for fuzzy-number-valued functions are discussed by means of the characteristic the- orems of nonabsolute fuzzy integrals and the embedding theorem,i.e.,the fuzzy number space can be embedded into a concrete Banach space.Several necessary and sufficient conditions and examples are given.
