This study compared the control effect of 110 g/L etoxazole SC,15%abamectin·etoxazole SC,30%cyetpyrafen SC,43%bifenazate SC and 1.8%abamectin EC five acaricides sprayed by unmanned aerial vehicle(UAV)on Panonychu...This study compared the control effect of 110 g/L etoxazole SC,15%abamectin·etoxazole SC,30%cyetpyrafen SC,43%bifenazate SC and 1.8%abamectin EC five acaricides sprayed by unmanned aerial vehicle(UAV)on Panonychus citri,aiming to screen out the appropriate acaricide for the control of this pest by UAV spraying.The results showed that 15%abamectin·etoxazole SC and 30%cyetpyrafen SC had the highest control efficacy,which remained above 90%14 d after application.Secondary performance was observed in 43%bifenazate SC and 110 g/L etoxazole SC,which demonstrated enhancing control effect.However,1.8%abamectin EC showed slower effect.Considering the control effect and population reduction rate of P.citri,15%abamectin·etoxazole SC and 30%cyetpyrafen SC were suggested as the effective acaricides for the control of this pest.展开更多
The finite/fixed-time stabilization and tracking control is currently a hot field in various systems since the faster convergence can be obtained. By contrast to the asymptotic stability,the finite-time stability poss...The finite/fixed-time stabilization and tracking control is currently a hot field in various systems since the faster convergence can be obtained. By contrast to the asymptotic stability,the finite-time stability possesses the better control performance and disturbance rejection property. Different from the finite-time stability, the fixed-time stability has a faster convergence speed and the upper bound of the settling time can be estimated. Moreover, the convergent time does not rely on the initial information.This work aims at presenting an overview of the finite/fixed-time stabilization and tracking control and its applications in engineering systems. Firstly, several fundamental definitions on the finite/fixed-time stability are recalled. Then, the research results on the finite/fixed-time stabilization and tracking control are reviewed in detail and categorized via diverse input signal structures and engineering applications. Finally, some challenging problems needed to be solved are presented.展开更多
[Objective]The paper was to screen a new ideal sustained-release,long-lasting and low-toxic pesticide and convenient and efficient pesticide application technology for controlling Ceratovacuna lanigera and Baliathrips...[Objective]The paper was to screen a new ideal sustained-release,long-lasting and low-toxic pesticide and convenient and efficient pesticide application technology for controlling Ceratovacuna lanigera and Baliathrips serratus. [Method]2% Imidacloprid GR were selected and applied in the soil for field efficacy trial. [Result] The optimum dosage of 2% imidacloprid GR was 30 kg/hm^2（ active ingredient 600 g）,which can be mixed with fertilizer（ 30 kg pesticide and 40-80 kg fertilizer per hm^2） once combined with sugarcane planting management or big ridging during February and June. The control effects against C. lanigera and B. serratus could be more than 98. 2% and 81. 1%,respectively. The actual yield and sugar content in various pesticide treatments were increased by 33 390 kg/hm^2 and 6. 6% respectively compared to blank control. [Conclusion]2% imidacloprid GR has good control effects on C. lanigera and B. serratus. It is a new pesticide with ideal sustained-release,long-lasting and low-toxin effects against C. lanigera and B. serratus. Therefore,it could be used alternatively with other pesticides,to delay production and development of drug resistance.展开更多
In order to provide a theoretical basis for apple cultivation techniques and to provide a reference for preparation of scientific management measures,the occurrence and damage status of apple little leaf in northern G...In order to provide a theoretical basis for apple cultivation techniques and to provide a reference for preparation of scientific management measures,the occurrence and damage status of apple little leaf in northern Guizhou was investigated,and fertilizer control test against the disease was also conducted.（1）Apple little leaf occurred from April to October in apple producing areas in northern Guizhou every year,with heavy incidence from April to May,light incidence from June to July,and the lightest incidence from August to October.（2） Effectiveness test showed that application of zinc sulfate fertilizer 135 g ＋ cow dung 10 kg received the best control effect,followed by zinc sulfate fertilizer 165 g ＋ cow dung 10 kg,then zinc sulfate fertilizer 105 g ＋ cow dung 10 kg and zinc sulfate fertilizer 150 g ＋ cow dung 10 kg.（3） Based on local environmental conditions,occurrence and damage situation,incidence conditions and fertilizer efficacy test,comprehensive prevention and control technology with rational supplement of zinc fertilizer could be used to control apple little leaf.展开更多
Complexity is one of the leading features of modem control systems. It is caused by the complex properties of controlled plants and the varied requirements in controller designs. In dealing with the control problems w...Complexity is one of the leading features of modem control systems. It is caused by the complex properties of controlled plants and the varied requirements in controller designs. In dealing with the control problems with complexity, in the past two decades, a lot of papers have been published that reported fruitful results on different theoretical backgrounds and with different methodologies, such as differential geometry-based design methods, hybrid system theory, switching control, neural network-based intelligent control, etc.展开更多
Recently, switched control systems have been attracting much attention m the control community because the problems are not only academically challenging for the inherent complexity, but also of practical importance d...Recently, switched control systems have been attracting much attention m the control community because the problems are not only academically challenging for the inherent complexity, but also of practical importance due to its wide ranges of applications in nature, engineering, and social sciences.展开更多
Wireless Sensor Network （WSN） is characterized by the dense deployment of sensor nodes that continuously observe physical phenomenon. The main advantages of WSN include its low cost, rapid deployment, self-organizat...Wireless Sensor Network （WSN） is characterized by the dense deployment of sensor nodes that continuously observe physical phenomenon. The main advantages of WSN include its low cost, rapid deployment, self-organization, and fault tolerance. WSN has received tremendous interests of various research communities,展开更多
It is our great pleasure to put up this special issue in Journal of Control Theory and Applications in honor of the 60th birthday of Professor Frank Lewis, who has made many significant contributions to the field of c...It is our great pleasure to put up this special issue in Journal of Control Theory and Applications in honor of the 60th birthday of Professor Frank Lewis, who has made many significant contributions to the field of control engineering through the years, and who is regarded as a pioneer in many areas in control and automation, which includes applied optimal control and geometric systems theory in his earlier research period, and his recent focus on intelligent nonlinear control,展开更多
The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory. In recent years control problems have been arising...The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory. In recent years control problems have been arising with increasing frequency in widely different areas, which cannot be addressed using conventional control techniques. The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where presence of large uncertainties as well as nonlinearities plays a major role. For instance, the design of unmanned aircraft, unmanned underwater vehicles, and automatic driving systems for automobiles are all typical examples of such difficult control problems. The large uncertainties concerning the plant may arise due to large external disturbances, large parameter variations because of faults in the system, or failure of some of the subsystems. In such cases, the controller has to determine the specific situation that exists at any instant, and take the appropriate control action. Accomplishing this rapidly, accurately, and in a stable fashion is the objective of control design.展开更多
Approximate dynamic programming (ADP) is a general and effective approach for solving optimal control and estimation problems by adapting to uncertain and nonconvex environments over time.
The numerical control technology application major in secondary vocational schools trains the technical workers of numerical control processing. Physics plays an irreplaceable role in promoting the study of numerical ...The numerical control technology application major in secondary vocational schools trains the technical workers of numerical control processing. Physics plays an irreplaceable role in promoting the study of numerical control major and provides a foundation for the knowledge of mechanical processing. Under the situation of popular numerical control specialty, physics teaching in secondary vocational schools is declining. The teachers analyzed the current situation of physics teaching of numerical control technology application major in secondary vocational schools, and proposed countermeasures to adapt to social changes and improve the effectiveness of physics teaching.展开更多
文摘This study compared the control effect of 110 g/L etoxazole SC,15%abamectin·etoxazole SC,30%cyetpyrafen SC,43%bifenazate SC and 1.8%abamectin EC five acaricides sprayed by unmanned aerial vehicle(UAV)on Panonychus citri,aiming to screen out the appropriate acaricide for the control of this pest by UAV spraying.The results showed that 15%abamectin·etoxazole SC and 30%cyetpyrafen SC had the highest control efficacy,which remained above 90%14 d after application.Secondary performance was observed in 43%bifenazate SC and 110 g/L etoxazole SC,which demonstrated enhancing control effect.However,1.8%abamectin EC showed slower effect.Considering the control effect and population reduction rate of P.citri,15%abamectin·etoxazole SC and 30%cyetpyrafen SC were suggested as the effective acaricides for the control of this pest.
基金partially supported by the National Natural Science Foundation of China(62003097,62121004,62033003,62073019)the Local Innovative and Research Teams Project of Guangdong Special Support Program(2019BT02X353)+2 种基金the Key Area Research and Development Program of Guangdong Province(2021B0101410005)the Joint Funds of Guangdong Basic and Applied Basic Research Foundation(2019A1515110505)。
文摘The finite/fixed-time stabilization and tracking control is currently a hot field in various systems since the faster convergence can be obtained. By contrast to the asymptotic stability,the finite-time stability possesses the better control performance and disturbance rejection property. Different from the finite-time stability, the fixed-time stability has a faster convergence speed and the upper bound of the settling time can be estimated. Moreover, the convergent time does not rely on the initial information.This work aims at presenting an overview of the finite/fixed-time stabilization and tracking control and its applications in engineering systems. Firstly, several fundamental definitions on the finite/fixed-time stability are recalled. Then, the research results on the finite/fixed-time stabilization and tracking control are reviewed in detail and categorized via diverse input signal structures and engineering applications. Finally, some challenging problems needed to be solved are presented.
基金Supported by Special Fund for China Agricultural Industry Research System(CARS-20-2-2)Special Fund for Agricultural Industry Research System of Yunnan Province(YNGZTX-4-92)
文摘[Objective]The paper was to screen a new ideal sustained-release,long-lasting and low-toxic pesticide and convenient and efficient pesticide application technology for controlling Ceratovacuna lanigera and Baliathrips serratus. [Method]2% Imidacloprid GR were selected and applied in the soil for field efficacy trial. [Result] The optimum dosage of 2% imidacloprid GR was 30 kg/hm^2（ active ingredient 600 g）,which can be mixed with fertilizer（ 30 kg pesticide and 40-80 kg fertilizer per hm^2） once combined with sugarcane planting management or big ridging during February and June. The control effects against C. lanigera and B. serratus could be more than 98. 2% and 81. 1%,respectively. The actual yield and sugar content in various pesticide treatments were increased by 33 390 kg/hm^2 and 6. 6% respectively compared to blank control. [Conclusion]2% imidacloprid GR has good control effects on C. lanigera and B. serratus. It is a new pesticide with ideal sustained-release,long-lasting and low-toxin effects against C. lanigera and B. serratus. Therefore,it could be used alternatively with other pesticides,to delay production and development of drug resistance.
文摘In order to provide a theoretical basis for apple cultivation techniques and to provide a reference for preparation of scientific management measures,the occurrence and damage status of apple little leaf in northern Guizhou was investigated,and fertilizer control test against the disease was also conducted.（1）Apple little leaf occurred from April to October in apple producing areas in northern Guizhou every year,with heavy incidence from April to May,light incidence from June to July,and the lightest incidence from August to October.（2） Effectiveness test showed that application of zinc sulfate fertilizer 135 g ＋ cow dung 10 kg received the best control effect,followed by zinc sulfate fertilizer 165 g ＋ cow dung 10 kg,then zinc sulfate fertilizer 105 g ＋ cow dung 10 kg and zinc sulfate fertilizer 150 g ＋ cow dung 10 kg.（3） Based on local environmental conditions,occurrence and damage situation,incidence conditions and fertilizer efficacy test,comprehensive prevention and control technology with rational supplement of zinc fertilizer could be used to control apple little leaf.
文摘Complexity is one of the leading features of modem control systems. It is caused by the complex properties of controlled plants and the varied requirements in controller designs. In dealing with the control problems with complexity, in the past two decades, a lot of papers have been published that reported fruitful results on different theoretical backgrounds and with different methodologies, such as differential geometry-based design methods, hybrid system theory, switching control, neural network-based intelligent control, etc.
文摘Recently, switched control systems have been attracting much attention m the control community because the problems are not only academically challenging for the inherent complexity, but also of practical importance due to its wide ranges of applications in nature, engineering, and social sciences.
文摘Wireless Sensor Network （WSN） is characterized by the dense deployment of sensor nodes that continuously observe physical phenomenon. The main advantages of WSN include its low cost, rapid deployment, self-organization, and fault tolerance. WSN has received tremendous interests of various research communities,
文摘It is our great pleasure to put up this special issue in Journal of Control Theory and Applications in honor of the 60th birthday of Professor Frank Lewis, who has made many significant contributions to the field of control engineering through the years, and who is regarded as a pioneer in many areas in control and automation, which includes applied optimal control and geometric systems theory in his earlier research period, and his recent focus on intelligent nonlinear control,
文摘The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory. In recent years control problems have been arising with increasing frequency in widely different areas, which cannot be addressed using conventional control techniques. The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where presence of large uncertainties as well as nonlinearities plays a major role. For instance, the design of unmanned aircraft, unmanned underwater vehicles, and automatic driving systems for automobiles are all typical examples of such difficult control problems. The large uncertainties concerning the plant may arise due to large external disturbances, large parameter variations because of faults in the system, or failure of some of the subsystems. In such cases, the controller has to determine the specific situation that exists at any instant, and take the appropriate control action. Accomplishing this rapidly, accurately, and in a stable fashion is the objective of control design.
文摘Approximate dynamic programming (ADP) is a general and effective approach for solving optimal control and estimation problems by adapting to uncertain and nonconvex environments over time.
文摘The numerical control technology application major in secondary vocational schools trains the technical workers of numerical control processing. Physics plays an irreplaceable role in promoting the study of numerical control major and provides a foundation for the knowledge of mechanical processing. Under the situation of popular numerical control specialty, physics teaching in secondary vocational schools is declining. The teachers analyzed the current situation of physics teaching of numerical control technology application major in secondary vocational schools, and proposed countermeasures to adapt to social changes and improve the effectiveness of physics teaching.
