自适应单神经元网络在耦合系统中的应用

基于神经网络PID控制和解耦系统的特点,应用一种针对多输入多输出解耦系统的单神经元PID解耦算法和结构,并在算法中增加了自适应学习速率,更好的实现对耦合系统的解耦控制。仿真结果表明这种单神经元PID解耦算法实现的控制比常规的PID解耦不仅具有较好的动态性能和稳态性能,而且还具有很强的自学习功能和自适应解耦能力。     

基于单神经元模糊自适应PID控制的加热炉温度控制器设计

加热炉温度控制器要求精度高、动态性能好、抗干扰能力强、检测功能全,而常规的PID控制策略难以满足要求。为此,提出一种单神经元模糊自适应PID控制算法,为提高系统的控温精度和响应快速性,将模糊控制引入单神经元自适应PID控制中,提出单神经元模糊PID控制。它运用有监督的Hebb学习规则在线修正PID参数,而神经元的比例、积分、微分学习速率则由Sugeno模糊逻辑系统根据系统的误差和误差变化量大小进行调整,使控制系统对动态过程信息的利用程度达到最优。Matlab仿真和实验结果表明,系统不仅具有自学习、自适应能力和鲁棒性,且动态性能和稳态性能都优于经典PID控制,超调量减小,上升时间和调节时间均减小。     

基于神经网络的永磁同步电机矢量控制

本文提出了一种利用神经元PID的永磁同步电机矢量控制方案。给出了永磁同步电机的数学模型、神经网络PID结构、算法以及控制系统的仿真结果。仿真结果表明该系统具有良好的动态性能。     

基于改进神经网络算法控制开关电源的研究

针对数字开关电源的控制策略问题,提出一种改进共轭梯度算法的BP神经网络PID控制系统.以BUCK变换器为研究对象,在BP神经网络PID算法的基础上,通过改进共轭梯度算法优化控制系统的调节时间和恢复速度,以提高数字开关电源系统的控制性能和输出性能.基于MATLAB软件完成系统建模进行仿真研究.结果表明:改进后的控制系统比...     

基于单神经元PID的并联机构稳定控制研究

并联机构由于非线性强、控制过程复杂,导致常规PID控制参数难以整定。为了实现对二自由度并联机构更精确的控制,结合神经网络,文中提出了一种基于单神经元的自适应PID控制策略,以实现PID控制参数的实时整定。通过dSPACE对被控对象进行半实物仿真,仿真结果表明,设计的单神经元PID控制器控制效果优于传统PID控制器。     

高压断路器三相永磁无刷直流电机机构控制算法研究

针对高压断路器三相永磁无刷直流电机机构,研究了不同控制策略下电机操动机构的运动特性.考虑高压断路器的分、合闸操作过程,建立了永磁无刷直流电机操动机构运动控制系统的仿真模型,采用数字式双闲环控制,内环为电流环,采用PI控制,外环为速度环,基于传统PID控制器、单神经元PID控制两种不同控制策略控制.通过对伺服控制系统的仿真分析得到了电机操动机构速度跟踪控制特性.结果表明,单神经元PID控制器能够较好的实现触头速度的跟踪控制,使其按理想运动特性曲线运动,是一种较理想、有效的控制方法.     

基于模糊自适应PID的炉温控制系统设计

电锅炉已成为寒冷地区供热采暖的主要设备,对于新疆地区尤为重要.电锅炉的温度控制系统由于存在非线性、滞后性以及时变性等特点,常规的PID控制器很难达到较好的控制效果.考虑到模糊控制能对复杂的非线性、时变系统进行很好的控制,但无法消除静态误差的特点,本设计将模糊控制和常规的PID控制相结合,提出一种模糊自适应PID控制器的新方法.并对电锅炉温度控制系统进行了抗扰动的仿真试验,结果表明,和常规的PID控制器及模糊PID复合控制器相比,模糊自适应PID控制改善了系统的动态性能和鲁棒性,达到了较好的控制效果.     

基于模糊PID参数自整定的温度控制系统的研究

工业温度控制系统具有非线性、时变性和滞后性等特性,严重影响温度控制的快速性和准确性,为了解决常规PID参数调节在温度控制中适应性差,调节效果不理想的问题,这里采用了模糊PID参数自整定控制方法,用模糊控制规则对PID参数进行修改,利用Matlab的Simulink仿真工具箱做了常规PID与模糊PID的仿真对比试验。仿真结果表明,模糊PID参数自整定控制效果在超调量和调节时间上都小于常规PID,提高系统快速性和准确性,改善了温度系统动态性能。     

多轴电机同步运动控制器设计

针对多轴电机同步控制问题,研究一种基于模糊-单神经元PID控制策略的同步控制器。使用研究的同步控制方法与常规PID算法进行对比分析。结果表明,相比基于常规PID算法的多轴电机同步运动控制器,在基于模糊-单神经元PID算法的多轴电机同步运动控制器作用下,各个电机之前的同步误差更小,当第二台电机发生载荷突变时,控制器能够有效抑制载荷突变对整个多轴电机系统的影响。基于模糊-单神经元PID算法的多轴电机同步运动控制器能够有效提升多轴电机同步运动系统的动态特性和稳定性。     

基于混合优化算法的神经元PID控制策略

为解决传统比例-积分-微分(PID)控制器在实际工业过程中难以满足控制要求的问题,将二次型性能指标引入到神经元的加权系数的调整中,并利用自学习功能构成了神经元自适应PID控制器.利用混沌优化算法和最速下降法结合起来的混合优化算法,对神经元自适应PID控制器的学习速率和神经元比例系数进行了优化.仿真实验和结果分析表明:该混合优化神经元自适应PID控制器具有很好的动态和静态性能,系统的稳定性和鲁棒性增强,学习参数选择的盲目性和对经验的高度依赖性降低.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.