加热炉温度是钢厂中重要控制参数之一,温度控制系统具有非线性、时变性、滞后性等特性。利用COM组件技术,运用MCGS(Monitor and Control Generated System)组态软件的可视化画面制作技术,利用MATLAB软件的丰富算法来完成模糊自适应PID控...加热炉温度是钢厂中重要控制参数之一,温度控制系统具有非线性、时变性、滞后性等特性。利用COM组件技术,运用MCGS(Monitor and Control Generated System)组态软件的可视化画面制作技术,利用MATLAB软件的丰富算法来完成模糊自适应PID控制,实现了稳定的温度控制系统的人机界面。结果表明,不仅获得强鲁棒性、强抗干扰性和满意的控制性能,同时提高了实时控制能力,方便地用于实际工业控制中。展开更多
Proportional integral plus feedforward (PI+FF) control was proposed for identifying the pipe temperature in hot water heating greenhouse. To get satisfying control result, ten coefficients must be adjusted properly. T...Proportional integral plus feedforward (PI+FF) control was proposed for identifying the pipe temperature in hot water heating greenhouse. To get satisfying control result, ten coefficients must be adjusted properly. The data for training and testing the radial basic function (RBF) neural-networks model of greenhouse were collected in a 1028 m2 multi-span glasshouse. Based on this model, a method of coefficients adjustment is described in this article.展开更多
A method to reach the globular weld structure of A356 aluminum alloy using stirring the localized semisolid zone during butt-joining is developed.Since the heat conductivity of this alloy is very high, the accurate co...A method to reach the globular weld structure of A356 aluminum alloy using stirring the localized semisolid zone during butt-joining is developed.Since the heat conductivity of this alloy is very high, the accurate controlling of temperature during joining must be considered.A gas heating system was used to heat up the nitrogen gas up to the required temperature.A dried and free oxygen gas was prepared when a stream of nitrogen gas could pass closely around a hot element.Hot and pure nitrogen gas flow through a precise ceramic nozzle was used to create a localized semisolid pool.At this stage a fine stirrer was introduced into the weld seam in order to mix the two sides into a single uniform joint.Substrates were moved in direction of joint line by a small trolley to avoid the deviation of nozzle from the joint line and its distance and angle from the substrate.A fixture system was used to hold two substrates together on the trolley.A narrow hot plate was located on the trolley to heat up the joint line due to high heat conductivity of aluminum.Effect of gas temperature was investigated on the microstructure and mechanical properties of weld seam.Results showed that increase in temperature promoted the final welding properties, and also at liquid fractions less than 50% joining was not fully practical.The best mechanical properties were achieved with liquid fraction of about 70%.展开更多
文摘加热炉温度是钢厂中重要控制参数之一,温度控制系统具有非线性、时变性、滞后性等特性。利用COM组件技术,运用MCGS(Monitor and Control Generated System)组态软件的可视化画面制作技术,利用MATLAB软件的丰富算法来完成模糊自适应PID控制,实现了稳定的温度控制系统的人机界面。结果表明,不仅获得强鲁棒性、强抗干扰性和满意的控制性能,同时提高了实时控制能力,方便地用于实际工业控制中。
基金Project (No. 2002C12021) supported by the Science and Technology Department of Zhejiang Province,China
文摘Proportional integral plus feedforward (PI+FF) control was proposed for identifying the pipe temperature in hot water heating greenhouse. To get satisfying control result, ten coefficients must be adjusted properly. The data for training and testing the radial basic function (RBF) neural-networks model of greenhouse were collected in a 1028 m2 multi-span glasshouse. Based on this model, a method of coefficients adjustment is described in this article.
文摘A method to reach the globular weld structure of A356 aluminum alloy using stirring the localized semisolid zone during butt-joining is developed.Since the heat conductivity of this alloy is very high, the accurate controlling of temperature during joining must be considered.A gas heating system was used to heat up the nitrogen gas up to the required temperature.A dried and free oxygen gas was prepared when a stream of nitrogen gas could pass closely around a hot element.Hot and pure nitrogen gas flow through a precise ceramic nozzle was used to create a localized semisolid pool.At this stage a fine stirrer was introduced into the weld seam in order to mix the two sides into a single uniform joint.Substrates were moved in direction of joint line by a small trolley to avoid the deviation of nozzle from the joint line and its distance and angle from the substrate.A fixture system was used to hold two substrates together on the trolley.A narrow hot plate was located on the trolley to heat up the joint line due to high heat conductivity of aluminum.Effect of gas temperature was investigated on the microstructure and mechanical properties of weld seam.Results showed that increase in temperature promoted the final welding properties, and also at liquid fractions less than 50% joining was not fully practical.The best mechanical properties were achieved with liquid fraction of about 70%.
