一种四螺旋混沌系统仿真研究

为了改善Lü系统的混沌特性,通过在混沌Lü系统上添加一维线性状态反馈控制器,构建了一个新的四维连续自治混沌系统,得到了奇异的四螺旋鲁棒混沌吸引子。利用相轨图、Lyapunov指数谱等数值方法,其最大Lyapunov指数为正值且几乎恒定不变,系统具有很好的鲁棒性.随控制参数变化,系统能够从四螺旋混沌吸引子演变成双螺旋混沌吸引子。通过在混沌Lü系统电路上外加一个简单的线性积分电路实现了新混沌系统的实验电路,实验仿真与数值方法所得结果有着很好的一致性。     

多参数恒Lyapunov指数谱Sprott-J系统及其数字硬件实现

在基本Sprott-J系统的基础上,引入四个系统参数并进行恒Lyapunov指数谱锁定,构建了一个多参数恒Lyapunov指数谱混沌系统。采用相轨图、Lyapunov指数谱和分岔图等动力学手段对系统进行了数值仿真。研究结果表明,系统对其中一个参数存在倍周期分岔和反向倍周期分岔等物理现象,而对另外三个参数则保持恒定的Lyapunov指数谱。基于微控制器MSP430F249设计了数字硬件电路,实现并验证了所构建的混沌系统。     

一种新的四维二次超混沌系统及其电路实现

在三维二次混沌系统的基础上,增加一个状态变量,构建了一种新的四维二次超混沌系统.对新的超混沌系统的Lyapunov指数谱和分岔图进行了分析;通过数值仿真,得到超混沌吸引子相图;设计了一个模拟电子电路,通过电路实验,在示波器上观察到超混沌吸引子相图.     

注入激光系统的混沌与超混沌行为

通过对一个注入激光系统的分岔图、李雅普诺夫（Lyapunov）指数谱、功率谱和相轨道的数值计算与分析，得到了系统出现不动点、极限环、混沌、超混沌的参数区间。为进一步研究该系统在混沌和起混沌状态下的统计性质奠定了基础。     

一个新的混沌系统及其电路设计与实现

提出了一个连续三维二次自治混沌系统.该系统与Lorenz、Rossler、Chen、Lu系统不同,它只含一个系统参数,但具有五个平衡点.通过理论分析、Lyapunov指数谱、分岔图以及电路设计与实验,验证了系统的混沌行为.     

基于FPGA的数字混沌序列的实现及性能分析

为了产生数字混沌PN序列,提出了一种基于FPGA平台的连续混沌数字化技术.针对一个混沌系统,利用理论和 数值仿真对系统的基本特性进行了分析,通过Lyapunov指数谱和分叉图对系统的状态转换进行了分析.在Matlab的Simulink 下,利用DSPBuilder设计了一个电路,并转换成VHDL代码程序,用Quartu...     

一种具有多对称同质吸引子的四维混沌系统的超级多稳定性研究

该文在一个经典3维混沌系统的基础上提出一个新的具有超级多稳定性的4维混沌系统.新系统具有一个线平衡点,可以产生无限多对称的同质吸引子.通过相轨图和庞加莱截面等方法分析了系统的混沌特性.重点利用相轨图、分岔图和Lyapunov指数谱等方法分析了初始条件对系统超级多稳定性的影响,分析表明该系统具有很大的初值变化范围,除零点...     

基于线性反馈控制的超混沌系统设计与电路实现

基于最新提出的简化Lorenz混沌系统,采用线性控制策略,设计了一个超混沌系统。利用相图、Lyapunov指数谱、分岔图以及Poincaré截面分析方法,详细地研究了系统参数变化时简化Lorenz超混沌系统的动力学行为,数值仿真结果显示,Lyapunov指数谱与分岔图分析一致。采用分立元件,设计并实现了该系统的模拟电子电路,通过调节电路中的可变电阻,观察到了该系统的极限环、叉式分岔、倍周期分岔、混沌和超混沌,以及由倍周期分岔而进入混沌的道路等动力学现象。数值仿真和电路实验结果表明,该系统具有丰富的动力学特性,且电路实验结果与数值仿真相吻合。     

六维分数阶Lorenz-duffing系统仿真

设计一个混沌行为复杂且具有物理学特性的整数阶混沌系统很难。为了解决这个问题,在整数阶混沌系统中引入了分数阶微分算子,并设计了一个六维分数阶Lorenz-duffing混沌系统;还重点分析了该分数阶混沌系统的平衡点和稳定性以及系统的吸引子、分岔图和Lyapunov指数谱;最后,设计该分数阶混沌电路,并利用Multisim软件仿真分析了该电路。仿真结果表明,该分数阶混沌系统能够产生混沌信号。     

一个新的四维超混沌系统的动力学分析及混沌反同步

提出了一个新的四维Chen-Qi-like混沌系统.通过计算该系统的时间序列的Lyapunov指数谱、Lyapunov 维数、分岔图、Poincaré截面图等分析了控制参数变化时,系统的非线性动力学特征.结果表明该新系统不但和Chen-Qi 系统族有类似的性质,而且又呈现不同的非线性特征.在微分方程不变性原理基础上,运...     

Technology innovation and process integrations for sub-100nm gate patterning

This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

Complete approach to automatic identification and subpixel center location for ellipse feature

To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.     

小角度扩展相关性近似算法分析

本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

A Versatile Mixed-Signal Pin Approach for Cost-Effective Test of Automotive ICs

Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

Optical vibration and deviation measurement of rotating machine parts

It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer （LDV）.