基于模糊PID算法的锅炉温度控制系统研究

温度控制在工业上的应用非常广泛,温度控制系统大惯性、大的延迟和非线性特征。针对这一特征应用PID控制算法和模糊算法相结合的方法,模糊PID算法用于锅炉温度控制系统的研究。并开发使用PIC单片机作为控制器芯片,应用模糊PID算法对电锅炉温度进行控制。本文介绍了锅炉温度系统的组成,系统的软件流程和模糊PID控制器的设计。     

基于DMC算法的单晶炉热场温度控制系统

介绍了以AT89C51单片机为核心的单晶炉热场温度控制系统的组成及工作原理.研究了动态矩阵控制(DMC)算法在单晶炉热场温度控制系统中的应用.给出了系统的硬件与软件设计的实现方法.研究表明,与PID控制结果相比较,应用动态矩阵控制算法能使系统具有更好的控制性能.     

模糊PID算法在泡沫玻璃窑炉温度控制中的应用

在工业窑炉温度控制系统中,由于被控参数具有时变性、非线性、不确定性,常规PID控制算法难以满足控制要求。该文采用模糊PID自整定控制算法,重点介绍模糊PID控制的基本原理及其在泡沫玻璃生产中的应用。     

气溶胶在线添加基质温度控制系统设计

为发展大气气溶胶基质辅助激光解吸附飞行时间质谱仪,研制了一套可用于调谐和控制气溶胶粒子在线添加基质蒸发/冷凝装置的温度测控系统.该系统以高性能的PIC16F877A单片机为控制核心,采用变速积分PID控制算法分别对加热池和冷凝管温度进行控制,单片机通过串口与计算机通信,在计算机上可以设定和显示温度以及温度曲线.实验结果表明:加热池的温度控制精度达±0.3 ℃,冷凝管的温度控制精度达±0.1 ℃,满足了气溶胶在线添加基质对温度的要求.     

MPCVD金刚石薄膜设备冷却水温控系统的设计

为了解决MPCVD设备运行时冷却水手动调节方式存在的弊端，实现冷却水温的自动调节，设计了一种冷却水温度控制系统。该系统以STM32单片机为控制器的核心，步进电机为执行机构，采用BP神经网络PID控制算法。对系统进行了仿真和试验验证，结果表明：该系统能够实现MPCVD设备生产制备金刚石薄膜过程中冷却水温度的自动控制，与传统的PID控制相比，系统采用BP神经网络PID控制算法时超调量更小，控制精度更高，均方根误差和平均绝对误差更小，具有更好的温度控制效果。     

基于数字PID的空调系统温度检测与控制设计

文中研究了空调控制系统中温度检测与控制算法及输出驱动电路的实现.系统的组成包括:温度检测与处理系统、A/D转换电路、单片机系统电路、键盘和显示电路以及输出驱动电路.系统的功能是由单片机中的控制程序来控制调节单相调功模块,从而实现温度控制,将从外界环境中采集到的温度信号转换成为高精度的数字信号,通过单片机进行处理在显示器上精确地显示出来.针对被测对象的温度在不同变化范围需要不同的PID 参数的特点,根据检测温度自动选择合适的一组PID 参数进行控制.实践表明该系统能可靠运行.     

应用单片机的热流道控制系统的设计

开发基于PID控制的单片机测控系统,利用单片机采集和控制温度,采用PID的改进算法,对热流道系统的流道板和各喷嘴进行精确的温度控制.     

基于CMAC神经网络的PID控制算法在温度控制中的仿真研究

为了更好地实现对工业过程温度的控制,文章设计了一种基于CMAC神经网络模型的PID控制算法。将该算法应用于温度控制中,研究了改变被控对象参数时的系统响应特性。仿真结果表明,该算法具有较强的自适应能力和鲁棒性,其性能优于常规PID控制算法。     

船用油漆导热油温度控制系统

针对导热油温度的有效控制以及效率的问题,对基于普通PID控制算法以及基于规则表的模糊控制算法进行了研究,对温度控制系统的温度采集模块、温度显示模块、声光报警模块以及加热模块等进行了改进,对温度控制系统的工作原理包括采用的模糊控制法、脉冲调制法等进行了分析。提出了一种基于89C52单片机以及基于模糊控制的船用油漆导热油温度控制系统,利用Proteus仿真平台构建温度控制系统的简化模型,分别对基于普通PID控制算法以及基于规则表的模糊控制算法进行了仿真。研究结果表明,采用基于规则表的模糊控制算法的导热油温度控制系统性能更好、效率更高,具有良好的温度控制效果,该系统能够在温度发生异常时声光报警并命令系统停止工作,能够满足实际生产加工的需求。     

基于C8051F020单片机的模糊PID温度测控系统设计

设计了一种基于C8051F020单片机的温度测控系统,该系统采用模糊PID方法进行温度控制,能克服普通的单片机PID温度控制系统的一些不足之处,达到较为理想的控制效果。给出了该系统的硬件结构,阐述了该系统的控制原理,提供了该系统的程序框图。     

Emerging chemical sensor technologies for use in on-line applications

Advances in instrumentation and process control capabilities are being driven by the increased sensitivity of analytical chemistry methods, the commoditization and ruggedization of instruments and associated electronics, and changing consumer concerns and expectations, as well as government regulations. The emergence of biotechnology methods for the detection of contaminants, and the miniaturization and ruggedization of more standard analytical instruments based on mass spectrometry and infrared spectroscopy will be discussed as related to on-line process monitoring.     

工程机械中嵌入式控制器的应用

嵌入式控制器已经应用于自动化办公,电子消费,智能仪器等多个领域,它有着非同寻常的适用范围和市场前景.从硬件设计,控制系统等各个部分的功能入手,介绍了一种基于ARM嵌八式控制器在工程机械中的应用.     

基于ARM9和DS18B20的汽车空调系统设计

采用ARM9内核芯片S3C2410为控制器,设计了一种嵌入式汽车空调温度控制系统,可实现现场显示、实时控制等功能。传感器使用了单总线数字式温度传感器DS18B20测量温度值。阐述了系统的构成原理和实现流程,重点介绍了系统的硬件结构。结合温度模糊控制算法,实验表明系统的硬件电路简单、控制精度好、可靠性高,且易于扩展。     

Electrohydraulic fatigue apparatus for testing at cryogenic temperature

A closed-loop electrohydraulic fatigue apparatus was constructed for testing from above room temperature to 77 K. Several important improvements in the electronics of the reference function generator and the servo controller over previous apparatus are described. The electronics allows cool-down of the specimen to 77 K at zero stress, correction for thermal contraction, and then cyclic fatigue testing under strain control, all without interruption of hydraulic power.     

Manufacturing Flexibility: Assessing Managerial Perception and Utilization

This paper presents an empirical study of how consumer electronics companies in Brazil deal with the issue of manufacturing flexibility. The main purpose is to provide an understanding into how flexibility is being perceived and utilized in a newly industrialized country. It begins by explaining the relevance of this study. The participation of Brazil in the world economy is important. Here, companies can be very flexible, based on low cost and an abundant skilled work force, yet flexibility has not been addressed. The paper explains how indicators were established to obtain an analytical structure with which to assess the managerial perception and the actual industrial use of flexibility. Finally, we show the most relevant results of our investigation of 16 leading firms in Brazil, including multinational ones. The findings are divided according to managerial perception of flexibility and effective utilization of flexibility in the organization. The paper concludes that firms in the consumer electronics industry in Brazil do not use flexibility practices in the same proportion that they perceive its importance.     

Effects of compound diamond slurry with graphene for lapping of sapphire wafers

Recently, sapphire has been used in a wide range of applications including optics, consumer electronics, and especially the rapidly growing LED wafer manuf     

Instrumented tracer for Lagrangian measurements in Rayleigh-Bénard convection

We have developed novel instrumentation for making Lagrangian measurements of temperature in diverse fluid flows. A small neutrally buoyant capsule is equipped with on-board electronics which measures temperature and transmits the data via a wireless radio frequency link to a desktop computer. The device has 80 dB dynamic range, resolving millikelvin changes in temperature with up to 100 ms sampling time. The capabilities of these "smart particles" are demonstrated in turbulent thermal convection in water. We measure temperature variations as the particle is advected by the convective motion and analyze its statistics. Additional use of cameras allow us to track the particle position and to report here the first direct measurement of Lagrangian heat flux transfer in Rayleigh-Bénard convection. The device shows promise for opening new research in a broad variety of fluid systems.     

SMT-TAB: A process planning system for PCB assembly using TAB and SMT

Process planning is a critical function in any manufacturing domain. This is especially true in the electronics manufacturing area where substantial heuristic and experiential knowledge is commonly used during process plan development. While research in computer-aided process planning (CAPP) has tended to concentrate in the machining realm, few CAPP systems have been developed for electronics manufacturing applications and more specifically for the printed circuit board (PCB) assembly domain. Besides, the CAPP systems that have been developed for this area have dealt with either insertion mount or surface mount PCB assembly processes only.Tape automated bonding (TAB), though a relatively new technology, is gaining importance in electronics assembly owing to its inherent advantages. The advent of fine pitch technology together with the ever increasing need for more inputs/outputs and greater pin counts in integrated circuit applications has enhanced the use of TAB technology in electronics manufacturing. This trend has been further augmented by the increasing need for compactness in consumer electronics.This research designed and developed a prototype CAPP system for the PCB assembly domain. The system developed generates a process plan for PCBs populated with surface mount and/or TAB components. An artificial-intelligence based expert system approach has been used in the design and development of the CAPP system. Outputs generated by the system are presented along with ideas for future research.     

离子束溅射工艺中的基片温度及其控制方法

离子束溅射技术以其在制备薄膜中的独特优点,成为获得高性能薄膜材料的重要手段。对于薄膜的制备,基片的温度是一个重要参数。主要从薄膜结构、应力和附着力三个方面总结了基片温度对离子束溅射工艺中薄膜生长的影响,并结合实际情况,介绍了在离子束刻蚀、溅射和磁控溅射镀膜工艺中的一些温度控制方法。在实际操作中,要根据沉淀薄膜的要求和离子束溅射的具体方法及设备,并结合基片本身的结构特点来考虑基片的控温措施及温度范围。     

单片机在电冰箱智能模糊控制中的应用

介绍了采用模糊控制技术实现冰箱温度控制，包括食品表面温度的模糊检测、基于三星单片机的模糊控制器、硬件电路和软件的设计。