Background Vacuum control and interlock system plays an important role in maintaining the vacuum condition for the normal operation of SESRI heavy ion accelerator.Vacuum failure of beam line at any position will cause...Background Vacuum control and interlock system plays an important role in maintaining the vacuum condition for the normal operation of SESRI heavy ion accelerator.Vacuum failure of beam line at any position will cause beam loss,experimental failure,and even serious consequences of accelerator shutdown.Methods This control system is designed and realized based on EPICS structure and PLC controller to realize the control and interlocking function of all kinds of vacuum equipment and ensure the operation and safety of the equipment.PLC level interlock and contact-based hardware interlock methods are used to realize both stability andflexibility.Results After a period of test running and actual operation,it is proved that this vacuum control and interlock system shows good stability,reliability andflexibility.Conclusion The vacuum control and interlock system in this paper realizes the design requirements of vacuum degree display,valve operability,correct and adjustable interlocking for the SESRI heavy ion accelerator vacuum system.展开更多
A novel pressure and vacuum continuous control system, which adopts a hybrid pump as pressure and vacuum source, is presented. The mathematical model of the system is developed. The theoretical simulation and analysis...A novel pressure and vacuum continuous control system, which adopts a hybrid pump as pressure and vacuum source, is presented. The mathematical model of the system is developed. The theoretical simulation and analysis on the system are implemented in order to study the relationships among the characteristics, parameters and working points of the system. The experimental investigations on the system characteristics are presented with the adoption ofa fuzzy-PID controller. The simulation and experimental results indicate that the pressure and vacuum continuous control system based on hybrid pump has good dynamic and static performance, strong robustness and satisfactory adaptability to various system parameters. According to the results, system can successfully gain high accuracy and fast response signal. Also, the mathematical model of system is also testified by the experimental results.展开更多
A hybrid neural network model,in which RH process(theoretical)model is combined organically with neural network(NN)and case-base reasoning(CBR),was established.The CBR method was used to select the operation mode and ...A hybrid neural network model,in which RH process(theoretical)model is combined organically with neural network(NN)and case-base reasoning(CBR),was established.The CBR method was used to select the operation mode and the RH operational guide parameters for different steel grades according to the initial conditions of molten steel,and a three-layer BP neural network was adopted to deal with nonlinear factors for improving and compensating the limitations of technological model for RH process control and end-point prediction.It was verified that the hybrid neural network is effective for improving the precision and calculation efficiency of the model.展开更多
Through simulation analyses of vacuum counter-pressure casting fuzzy control systems based on MATLAB, fuzzy control systems designed by simulation can track technical route established well. When transmission function...Through simulation analyses of vacuum counter-pressure casting fuzzy control systems based on MATLAB, fuzzy control systems designed by simulation can track technical route established well. When transmission functions of vacuum counter-pressure casting controlled objects are changed in operation, fuzzy control systems can carry on self-regulation and stabilize quickly, and embody the advantages of fleet response velocity and little adjusting quantity. The design of vacuum counter-pressure casting fuzzy control systems is accelerated and improved greatly by simulation based on MATLAB. Meanwhile, their design is accurate and reliable. Moreover, microstructure and properties of thin-wall aluminum alloy castings are improved effectively by using fuzzy control systems.展开更多
The principle and working process of Vacuum Resin Shot Dosing Equipment(VRSDE) are analyzed and the characteristics of IP1612-220PLC (Programmable Logical Controller) areintroduced briefly at first. Then the authors d...The principle and working process of Vacuum Resin Shot Dosing Equipment(VRSDE) are analyzed and the characteristics of IP1612-220PLC (Programmable Logical Controller) areintroduced briefly at first. Then the authors discuss the flow of program, the assignment of PLCI/O ports, the wiring diagram, and the ladder logic program of the PLC control system of VRSDE indetail. Some application issues of the system are accounted for in addition. Finally, according tothe information acquired from users, the authors draw the conclusion: this system owns a highreliability and a-vailability and greatly improves the automatic degree of VRDE.展开更多
This paper discusses some crucial problems arising in the implementation of the inelli-gent control of the vacuum distillation,such as the analysis of the plant characteristics,con-trol strategy selection,knowledge re...This paper discusses some crucial problems arising in the implementation of the inelli-gent control of the vacuum distillation,such as the analysis of the plant characteristics,con-trol strategy selection,knowledge representation,specification of maintenance strategy forthe knowledge base and accomplishment of the control system,etc.At the same time,wegive a concrete system along with its results and evaluations.展开更多
文摘Background Vacuum control and interlock system plays an important role in maintaining the vacuum condition for the normal operation of SESRI heavy ion accelerator.Vacuum failure of beam line at any position will cause beam loss,experimental failure,and even serious consequences of accelerator shutdown.Methods This control system is designed and realized based on EPICS structure and PLC controller to realize the control and interlocking function of all kinds of vacuum equipment and ensure the operation and safety of the equipment.PLC level interlock and contact-based hardware interlock methods are used to realize both stability andflexibility.Results After a period of test running and actual operation,it is proved that this vacuum control and interlock system shows good stability,reliability andflexibility.Conclusion The vacuum control and interlock system in this paper realizes the design requirements of vacuum degree display,valve operability,correct and adjustable interlocking for the SESRI heavy ion accelerator vacuum system.
基金This project is supported by National Natural Science Foundation of China (No.50675075).
文摘A novel pressure and vacuum continuous control system, which adopts a hybrid pump as pressure and vacuum source, is presented. The mathematical model of the system is developed. The theoretical simulation and analysis on the system are implemented in order to study the relationships among the characteristics, parameters and working points of the system. The experimental investigations on the system characteristics are presented with the adoption ofa fuzzy-PID controller. The simulation and experimental results indicate that the pressure and vacuum continuous control system based on hybrid pump has good dynamic and static performance, strong robustness and satisfactory adaptability to various system parameters. According to the results, system can successfully gain high accuracy and fast response signal. Also, the mathematical model of system is also testified by the experimental results.
基金Item Sponsored by National Natural Science Foundation of China(50074026)
文摘A hybrid neural network model,in which RH process(theoretical)model is combined organically with neural network(NN)and case-base reasoning(CBR),was established.The CBR method was used to select the operation mode and the RH operational guide parameters for different steel grades according to the initial conditions of molten steel,and a three-layer BP neural network was adopted to deal with nonlinear factors for improving and compensating the limitations of technological model for RH process control and end-point prediction.It was verified that the hybrid neural network is effective for improving the precision and calculation efficiency of the model.
基金Project(BB200300088) supported by the Commission of Science Technology and Industry for National Defence Fund ofChina
文摘Through simulation analyses of vacuum counter-pressure casting fuzzy control systems based on MATLAB, fuzzy control systems designed by simulation can track technical route established well. When transmission functions of vacuum counter-pressure casting controlled objects are changed in operation, fuzzy control systems can carry on self-regulation and stabilize quickly, and embody the advantages of fleet response velocity and little adjusting quantity. The design of vacuum counter-pressure casting fuzzy control systems is accelerated and improved greatly by simulation based on MATLAB. Meanwhile, their design is accurate and reliable. Moreover, microstructure and properties of thin-wall aluminum alloy castings are improved effectively by using fuzzy control systems.
文摘The principle and working process of Vacuum Resin Shot Dosing Equipment(VRSDE) are analyzed and the characteristics of IP1612-220PLC (Programmable Logical Controller) areintroduced briefly at first. Then the authors discuss the flow of program, the assignment of PLCI/O ports, the wiring diagram, and the ladder logic program of the PLC control system of VRSDE indetail. Some application issues of the system are accounted for in addition. Finally, according tothe information acquired from users, the authors draw the conclusion: this system owns a highreliability and a-vailability and greatly improves the automatic degree of VRDE.
基金Supported by the High Technology Research and Development Programme of ChinaNational Natural Science Foundation of China and China Petro-chemical Corporation.
文摘This paper discusses some crucial problems arising in the implementation of the inelli-gent control of the vacuum distillation,such as the analysis of the plant characteristics,con-trol strategy selection,knowledge representation,specification of maintenance strategy forthe knowledge base and accomplishment of the control system,etc.At the same time,wegive a concrete system along with its results and evaluations.
文摘为提高红托竹荪干燥品质并获得最佳干燥工艺,采用真空红外干燥(vacuum infrared drying,VID)、气流冲击干燥(air impingement drying,AID)、控湿干燥(moisture control drying,MCD)等不同干燥方式对红托竹荪进行对比研究,以热风干燥(hot air drying,HAD)作为对照组,研究不同干燥方式及温度对红托竹荪干燥品质的影响。试验结果表明不同干燥方式对竹荪宏观品质产生了显著影响,其中MCD可获得最小的色差∆E和收缩率,AID则能够保证较高的复水比;干燥速率方面,MCD在前期能够获得较高的干燥速率,但后期干燥速率会放缓,而AID在整个干燥过程都具有较高的干燥速率,干燥时间较短;在成分保留上,MCD可以保留较高含量的多糖、三萜和黄酮,而采用VID可以有效保护多酚。单位能耗随干燥温度的升高明显降低,不同方式下VID的干燥能耗值整体偏大,MCD的单位能耗最低(18.82 kW·h/kg)。通过主成分分析法,上述干燥方式对红托竹荪综合评分后得到的结果排序为:MCD>AID>VID>HAD,MCD干燥方式中采用60℃相对湿度为40%,保湿时间15min的干燥工艺综合品质较佳,在此加工方式下的红托竹荪综合评分为2.94,该研究可为红托竹荪高品质干燥提供一定参考。
