The effects of super absorbent polymers （SAP） on yield as well as water-saving and drought-escaping mechanism in spring maize in the seasonal drought region were studied. As shown by the results, during the seasonal...The effects of super absorbent polymers （SAP） on yield as well as water-saving and drought-escaping mechanism in spring maize in the seasonal drought region were studied. As shown by the results, during the seasonal drought in southern China, SAP treatment promoted the soil moisture, improved the capability of absorption and transportation of roots, promoted physiological and biochemical functions, increased the chlorophyll content, photosynthetic rate and intercellular CO2 concentration, and reduced the stomatal conductance and transplre.tion rate. As a result, the economic characters of spring maize were improved, and the yield was increased.展开更多
The low altitude airspace will be open in China, general aviation flights are tremendously increased. Whether aircrafts can fly safely and how to determine the requirements of safety flight are the problems needed to ...The low altitude airspace will be open in China, general aviation flights are tremendously increased. Whether aircrafts can fly safely and how to determine the requirements of safety flight are the problems needed to be confirmed. Under this circumstances, based on the international Civil Aviation Organization（ICAO） criteria and the standards made by CAAC, this paper adopts the ＂See and Avoid＂ principle. Under the binding conditions of flight rules, visibility requirements, responding time, the aircraft speed, circle banking angle or the climbing angle, based on its study on aircraft dynamics principles, this paper establishes a mathematical collision avoidance model for head-to-head traffic and crossing converging traffic at the same level. And the safety separation requirements of the aircrafts in low altitude flight are equantitatively analyzed. Finally, the Matlab software is used to analyze the above method. The result shows that the safe traffic avoidance of the converging traffic at the same level meets certain flight conditions, while intersecting the traffic at the same level can safely avoid the collision.展开更多
Robotic lawn mowers available in markets are much more complicated with high cost, hence, a new robot is designed in the research. In detail, the control system is made up of Arduino Mega2560 and 11 sensors and the ro...Robotic lawn mowers available in markets are much more complicated with high cost, hence, a new robot is designed in the research. In detail, the control system is made up of Arduino Mega2560 and 11 sensors and the robot works with four wheels （two front and back wheels） driven by an electric motor. Furthermore, the platform of lawn-mowing is designed semicircle, equipped with three small high- speed and low-power electric motors; the cutting distance is determined by width of motherboard. In addition, the hardware of the system is made up of circuit control and working machines, of which the former includes a single chip unit, a wireless remote control, a sensor unit, an infrared array module, a driving module of electric motor, a display unit and a power source; the latter includes a mowing platform and a sensor window. In addition, the related software is programmed using C language and modular programming involving PWM program, Hall sensor program, liquid-crys- tal display, tilt program, supersonic sounding program, infrared obstacle-avoidance program, parking program, and remote control program. After hardware was adjust- ed, the robotic lawn mower was tested for multiple times in a standard lawn, and a satisfied effect was achieved.展开更多
Grapevine shelter cultivation produces some influence on the quality of grape berry,at the same time of reducing the occurrence of diseases.Under the condition of rain-shelter cultivation,the effects of microenvironme...Grapevine shelter cultivation produces some influence on the quality of grape berry,at the same time of reducing the occurrence of diseases.Under the condition of rain-shelter cultivation,the effects of microenvironment,such as light,temperature and humidity,on the quality of grape berry were investigated in this paper.In addition,the relationships between microenvironmental changes and sugar,acid,color,aromatic substances and phenolic substances contents of the grape berry were analyzed.The current research status was analyzed,and the future study direction was discussed.展开更多
In order to improve a mobile robot＇s autonomy in unknown environments, a novel intelligent controller is designed. The proposed controller is based on fuzzy logic with the aim of assisting a multi-sensor equipped mob...In order to improve a mobile robot＇s autonomy in unknown environments, a novel intelligent controller is designed. The proposed controller is based on fuzzy logic with the aim of assisting a multi-sensor equipped mobile robot to safely navigate in an indoor environment. First, the designs of two behaviors for a robot＇s autonomous navigation are described, including path tracking and obstacle avoidance, which emulate human driving behaviors and reduce the complexity of the robot＇s navigation problems in unknown environments. Secondly, the two behaviors are combined by using a finite state machine （FSM）, which ensures that the robot can safely track a predefined path in an unknown indoor environment. The inputs to this controller are the readings from the sensors. The corresponding output is the desired direction of the robot. Finally, both the simulation and experimental results verify the effectiveness of the proposed method.展开更多
基金Supported by Key Projects in the National Science&TechnologyPillar Program(2006BAD04B07-2)Sic-tech Innovation Projectof Hunan Academy of Agricultural Sciences(2009hnnkycx30)~~
文摘The effects of super absorbent polymers （SAP） on yield as well as water-saving and drought-escaping mechanism in spring maize in the seasonal drought region were studied. As shown by the results, during the seasonal drought in southern China, SAP treatment promoted the soil moisture, improved the capability of absorption and transportation of roots, promoted physiological and biochemical functions, increased the chlorophyll content, photosynthetic rate and intercellular CO2 concentration, and reduced the stomatal conductance and transplre.tion rate. As a result, the economic characters of spring maize were improved, and the yield was increased.
文摘The low altitude airspace will be open in China, general aviation flights are tremendously increased. Whether aircrafts can fly safely and how to determine the requirements of safety flight are the problems needed to be confirmed. Under this circumstances, based on the international Civil Aviation Organization（ICAO） criteria and the standards made by CAAC, this paper adopts the ＂See and Avoid＂ principle. Under the binding conditions of flight rules, visibility requirements, responding time, the aircraft speed, circle banking angle or the climbing angle, based on its study on aircraft dynamics principles, this paper establishes a mathematical collision avoidance model for head-to-head traffic and crossing converging traffic at the same level. And the safety separation requirements of the aircrafts in low altitude flight are equantitatively analyzed. Finally, the Matlab software is used to analyze the above method. The result shows that the safe traffic avoidance of the converging traffic at the same level meets certain flight conditions, while intersecting the traffic at the same level can safely avoid the collision.
基金Supported by National Natural Science Foundation of China (11275164)~~
文摘Robotic lawn mowers available in markets are much more complicated with high cost, hence, a new robot is designed in the research. In detail, the control system is made up of Arduino Mega2560 and 11 sensors and the robot works with four wheels （two front and back wheels） driven by an electric motor. Furthermore, the platform of lawn-mowing is designed semicircle, equipped with three small high- speed and low-power electric motors; the cutting distance is determined by width of motherboard. In addition, the hardware of the system is made up of circuit control and working machines, of which the former includes a single chip unit, a wireless remote control, a sensor unit, an infrared array module, a driving module of electric motor, a display unit and a power source; the latter includes a mowing platform and a sensor window. In addition, the related software is programmed using C language and modular programming involving PWM program, Hall sensor program, liquid-crys- tal display, tilt program, supersonic sounding program, infrared obstacle-avoidance program, parking program, and remote control program. After hardware was adjust- ed, the robotic lawn mower was tested for multiple times in a standard lawn, and a satisfied effect was achieved.
文摘Grapevine shelter cultivation produces some influence on the quality of grape berry,at the same time of reducing the occurrence of diseases.Under the condition of rain-shelter cultivation,the effects of microenvironment,such as light,temperature and humidity,on the quality of grape berry were investigated in this paper.In addition,the relationships between microenvironmental changes and sugar,acid,color,aromatic substances and phenolic substances contents of the grape berry were analyzed.The current research status was analyzed,and the future study direction was discussed.
基金Cultivation Fund for Innovation Project of Ministry of Education (No.708045)
文摘In order to improve a mobile robot＇s autonomy in unknown environments, a novel intelligent controller is designed. The proposed controller is based on fuzzy logic with the aim of assisting a multi-sensor equipped mobile robot to safely navigate in an indoor environment. First, the designs of two behaviors for a robot＇s autonomous navigation are described, including path tracking and obstacle avoidance, which emulate human driving behaviors and reduce the complexity of the robot＇s navigation problems in unknown environments. Secondly, the two behaviors are combined by using a finite state machine （FSM）, which ensures that the robot can safely track a predefined path in an unknown indoor environment. The inputs to this controller are the readings from the sensors. The corresponding output is the desired direction of the robot. Finally, both the simulation and experimental results verify the effectiveness of the proposed method.
