10 Betula luminifera trees were chosen from biennial forest as test material in Zhentou Forestry Station,Jixi County,Anhui Province,from March to October in 2004.Every 10 days from March 10 on the indexes of growing c...10 Betula luminifera trees were chosen from biennial forest as test material in Zhentou Forestry Station,Jixi County,Anhui Province,from March to October in 2004.Every 10 days from March 10 on the indexes of growing characteristics were investigated,such as the leading shoot,the length of side shoot and thick degree,etc.The results showed the growth rhythm,lots of leaves forming in the middle of March,flower blooming at the last ten days of March and the first ten days of April,the fruit becoming mature in May,leaves falling in the first ten days of November.During one year’s growing period,both the leading shoot and diameter breast height of B.luminifera had three obviously living period,appearing respectively from the beginning of May to the last ten days of May,from the last ten days of June to the middle of July and from the middle of August to the beginning of September,among them the increment in the second period was the largest,the third was the least one.The increment in the 3 periods took the main proportion of the whole year.This paper purposed to put forward effective feasible technological measure for nurturing management of young stand.展开更多
This paper proposes a sliding mode controller based on robust model reference adaptive proportional-integral(RMRA-PI)control for a stand-alone voltage source inverter(SA-VSI).The proposed controller has two control lo...This paper proposes a sliding mode controller based on robust model reference adaptive proportional-integral(RMRA-PI)control for a stand-alone voltage source inverter(SA-VSI).The proposed controller has two control loops where the coefficients of PI controller are regulated by the adaptive sliding law.This method is used to regulate the output voltage of the inverter under different load conditions and uncertainty,and adapts the output to the reference model to reduce the total harmonic distortion(THD).In this paper,the stability of the proposed controller is proven by using Lyapunov's theory and Barbalet’s lemma.The proposed controller performs well in voltage regulation such as low THD under sudden load change and uncertainty.Also,the results of the proposed controller are compared with PI controller to show the effectiveness of the presented control system.展开更多
文摘10 Betula luminifera trees were chosen from biennial forest as test material in Zhentou Forestry Station,Jixi County,Anhui Province,from March to October in 2004.Every 10 days from March 10 on the indexes of growing characteristics were investigated,such as the leading shoot,the length of side shoot and thick degree,etc.The results showed the growth rhythm,lots of leaves forming in the middle of March,flower blooming at the last ten days of March and the first ten days of April,the fruit becoming mature in May,leaves falling in the first ten days of November.During one year’s growing period,both the leading shoot and diameter breast height of B.luminifera had three obviously living period,appearing respectively from the beginning of May to the last ten days of May,from the last ten days of June to the middle of July and from the middle of August to the beginning of September,among them the increment in the second period was the largest,the third was the least one.The increment in the 3 periods took the main proportion of the whole year.This paper purposed to put forward effective feasible technological measure for nurturing management of young stand.
文摘This paper proposes a sliding mode controller based on robust model reference adaptive proportional-integral(RMRA-PI)control for a stand-alone voltage source inverter(SA-VSI).The proposed controller has two control loops where the coefficients of PI controller are regulated by the adaptive sliding law.This method is used to regulate the output voltage of the inverter under different load conditions and uncertainty,and adapts the output to the reference model to reduce the total harmonic distortion(THD).In this paper,the stability of the proposed controller is proven by using Lyapunov's theory and Barbalet’s lemma.The proposed controller performs well in voltage regulation such as low THD under sudden load change and uncertainty.Also,the results of the proposed controller are compared with PI controller to show the effectiveness of the presented control system.
