The study was conducted to reduce blast damage, the use of pesticides residue, environment pollution and control costs, and to make a significant contribution to the improvement of grain production, quality and agricu...The study was conducted to reduce blast damage, the use of pesticides residue, environment pollution and control costs, and to make a significant contribution to the improvement of grain production, quality and agriculture ecological environment. Over these years, by the methods of systematical monitoring, regular surveys, field investigation, rice blast resistance identification, experiments and meteorological data analysis, the study on comprehensive prevention and control of rice blast in Nanchong City was conducted. The results showed that the rice varieties more sensitive to blast had a higher incidence of severe blast disease. Replacing,varieties with different source of resistance every three to five years and reasonable variety distribution can effectively reduce the prevalence of rice blast. Appropriate treatment of infected rice straw and pathogen, seed disinfection, seedling disinfection, and pesticide application at transplanting and etc. can delay blast occurrence and reduce the damage caused by blast. By analyzing the blast control efficiency of pesticides applied at different growth stages, we found that best control efficiency against blast was achieved by spraying pesticide twice during the whole growth stage, once 3 d before transplanting or 10 d after transplanting; and once at initial heading stage. Spraying 525 g/hm^2 75% tricyclazole was proven to be the best dosage for blast control. However, 375-450 g/hm^2 75% tricyclazole is enough if the blast incidence is not severe, or the rice varieties are slightly susceptible to blast.The control efficiency against leaf blast between 4% kasugamycin and 20% tricyclazole had no significant difference, but was significantly higher than that of 100 billion spores/g of Bacillus subtilis. The control efficiency against neck blast had no significant difference among 4% kasugamycin, 20% tricyclazole and 100 billion spores/g of B. subtilis. 450 g/hm^2 75% tricyclazole had better control efficiency against neck blast than 2 250 g/hm^2 2% 800 million spores/g Jinggangmycin-wax bud bacteria SC, 1 050 g/hm^2 41% kasugamycin-isoprothiolane WP and 900 g/hm^2 41%kasugamycin-isoprothiolane WP. The frequency of severe blast incidence in Nanchong City has reached 50% since 1997. The rice blast disease has been effectively controlled by comprehensive prevention and control technology, reducing the production loss to less than 2%, and pesticides by 4 523 t in total. In 2014, 327000 t rice grains were approved as pollution-free, green and organic agricultural products, indicating that the blast control measures produced great economic, social and ecological values.展开更多
Reproductive organ disease of geese is an endemic and multiple infectious disease in large-scale breeding of breeding geese, especially in anti-season production, which brings a great economic loss to goose production...Reproductive organ disease of geese is an endemic and multiple infectious disease in large-scale breeding of breeding geese, especially in anti-season production, which brings a great economic loss to goose production. To make effective prevention and control of reproductive organ disease of breeding geese under the anti-season breeding mode, the characteristics of control principles of infectious diseases of the poultry and the occurrence and prevalence of reproductive organ disease must be combined, so as to carry out scientific prevention and control.At the same time, according to the climate characteristics of summer, the feeding and management of breeding geese and water quality control should also be done well, and many corresponding measures should also be taken, thus obtaining better effect.展开更多
The control problem of trajectory based path following for passenger vehicles is studied. Comprehensive nonlinear vehicle model is utilized for simulation vehicle response during various maneuvers in MATLAB/Simulink. ...The control problem of trajectory based path following for passenger vehicles is studied. Comprehensive nonlinear vehicle model is utilized for simulation vehicle response during various maneuvers in MATLAB/Simulink. In order to follow desired path, a driver model is developed to enhance closed loop driver/vehicle model. Then, linear quadratic regulator(LQR) controller is developed which regulates direct yaw moment and corrective steering angle on wheels. Particle swam optimization(PSO) method is utilized to optimize the LQR controller for various dynamic conditions. Simulation results indicate that, over various maneuvers, side slip angle and lateral acceleration can be reduced by 10% and 15%, respectively, which sustain the vehicle stable. Also, anti-lock brake system is designed for longitudinal dynamics of vehicle to achieve desired slip during braking and accelerating. Proposed comprehensive controller demonstrates that vehicle steerability can increase by about 15% during severe braking by preventing wheel from locking and reducing stopping distance.展开更多
The origins and main control methods of gas in coal seams were introduced cursorily, and the processes that need to be done in controlling gas, which includes prediction of gas emissions, drainage systems, the means o...The origins and main control methods of gas in coal seams were introduced cursorily, and the processes that need to be done in controlling gas, which includes prediction of gas emissions, drainage systems, the means of prevention of gas outbursts, and some suggestions were put forward. The characteristic of different gas emissions and the corresponding counter measures were presented, and & case study of simultaneous extraction of coal and gas in Xieyi Coal Mine was carried out by coal mining and gas extraction without coal-pillar. The field application shows that gas drainage ratio in panel 5121(0) averages about 90% and reaches as high as 95~/0, which will give beneficial references to gas control in coal mines.展开更多
基金Supported by Notice on the First Batch of National Modern Agricultural Demonstration Zone by the Ministry of Agriculture(Agricultural Project No.[2010]22)One of the Major Pest and Disease Early Warning and Prevention Research Programs for Main Grain and Oil Crops(N1997-ZC002)~~
文摘The study was conducted to reduce blast damage, the use of pesticides residue, environment pollution and control costs, and to make a significant contribution to the improvement of grain production, quality and agriculture ecological environment. Over these years, by the methods of systematical monitoring, regular surveys, field investigation, rice blast resistance identification, experiments and meteorological data analysis, the study on comprehensive prevention and control of rice blast in Nanchong City was conducted. The results showed that the rice varieties more sensitive to blast had a higher incidence of severe blast disease. Replacing,varieties with different source of resistance every three to five years and reasonable variety distribution can effectively reduce the prevalence of rice blast. Appropriate treatment of infected rice straw and pathogen, seed disinfection, seedling disinfection, and pesticide application at transplanting and etc. can delay blast occurrence and reduce the damage caused by blast. By analyzing the blast control efficiency of pesticides applied at different growth stages, we found that best control efficiency against blast was achieved by spraying pesticide twice during the whole growth stage, once 3 d before transplanting or 10 d after transplanting; and once at initial heading stage. Spraying 525 g/hm^2 75% tricyclazole was proven to be the best dosage for blast control. However, 375-450 g/hm^2 75% tricyclazole is enough if the blast incidence is not severe, or the rice varieties are slightly susceptible to blast.The control efficiency against leaf blast between 4% kasugamycin and 20% tricyclazole had no significant difference, but was significantly higher than that of 100 billion spores/g of Bacillus subtilis. The control efficiency against neck blast had no significant difference among 4% kasugamycin, 20% tricyclazole and 100 billion spores/g of B. subtilis. 450 g/hm^2 75% tricyclazole had better control efficiency against neck blast than 2 250 g/hm^2 2% 800 million spores/g Jinggangmycin-wax bud bacteria SC, 1 050 g/hm^2 41% kasugamycin-isoprothiolane WP and 900 g/hm^2 41%kasugamycin-isoprothiolane WP. The frequency of severe blast incidence in Nanchong City has reached 50% since 1997. The rice blast disease has been effectively controlled by comprehensive prevention and control technology, reducing the production loss to less than 2%, and pesticides by 4 523 t in total. In 2014, 327000 t rice grains were approved as pollution-free, green and organic agricultural products, indicating that the blast control measures produced great economic, social and ecological values.
基金Supported by Agricultural Science and Technology Supporting Program of Huai'an City in Jiangsu Province(No.:SN13057)~~
文摘Reproductive organ disease of geese is an endemic and multiple infectious disease in large-scale breeding of breeding geese, especially in anti-season production, which brings a great economic loss to goose production. To make effective prevention and control of reproductive organ disease of breeding geese under the anti-season breeding mode, the characteristics of control principles of infectious diseases of the poultry and the occurrence and prevalence of reproductive organ disease must be combined, so as to carry out scientific prevention and control.At the same time, according to the climate characteristics of summer, the feeding and management of breeding geese and water quality control should also be done well, and many corresponding measures should also be taken, thus obtaining better effect.
文摘The control problem of trajectory based path following for passenger vehicles is studied. Comprehensive nonlinear vehicle model is utilized for simulation vehicle response during various maneuvers in MATLAB/Simulink. In order to follow desired path, a driver model is developed to enhance closed loop driver/vehicle model. Then, linear quadratic regulator(LQR) controller is developed which regulates direct yaw moment and corrective steering angle on wheels. Particle swam optimization(PSO) method is utilized to optimize the LQR controller for various dynamic conditions. Simulation results indicate that, over various maneuvers, side slip angle and lateral acceleration can be reduced by 10% and 15%, respectively, which sustain the vehicle stable. Also, anti-lock brake system is designed for longitudinal dynamics of vehicle to achieve desired slip during braking and accelerating. Proposed comprehensive controller demonstrates that vehicle steerability can increase by about 15% during severe braking by preventing wheel from locking and reducing stopping distance.
文摘The origins and main control methods of gas in coal seams were introduced cursorily, and the processes that need to be done in controlling gas, which includes prediction of gas emissions, drainage systems, the means of prevention of gas outbursts, and some suggestions were put forward. The characteristic of different gas emissions and the corresponding counter measures were presented, and & case study of simultaneous extraction of coal and gas in Xieyi Coal Mine was carried out by coal mining and gas extraction without coal-pillar. The field application shows that gas drainage ratio in panel 5121(0) averages about 90% and reaches as high as 95~/0, which will give beneficial references to gas control in coal mines.