基于FDO非线性预测方法的翼伞航迹跟踪控制

在翼伞系统的状态空间模型的基础上,分析了翼伞的归航轨迹,给出翼伞轨迹跟踪控制问题的数学描述.针对翼伞归航飞行过程中,受到较大的外干扰及不确定性影响,提出基于模糊干扰观测器(FDO)的非线性预测控制策略,设计了翼伞归航系统航迹跟踪控制器.通过仿真试验,表明该飞控系统具有良好鲁棒特性和抗干扰特性.     

翼伞转弯机理及其影响因素仿真分析

翼伞系统要实现精确空投的目的,其良好的转弯性能极其重要。本文以典型翼伞系统为对象,深入分析了翼伞的转弯机制,并建立了翼伞系统六自由度非线性模型。通过仿真实验,重点研究了翼伞的航向安定性和阻力方向舵对翼伞系统转弯性能的影响,所得结论可为翼伞系统的设计提供一定的理论参考。     

相互作用多模型跟踪过程中的航迹外推算法

提出运用IMM对目标进行跟踪时的航迹外推算法,解决了机动目标跟踪中的航迹外推问题。利用历史信息和转移概率推导出模型预测概率,结合单一模型的预测航迹和模型预测概率得到了相互作用多模型跟踪过程中的外推航迹。通过Monte-carlo仿真表明,运用外推方法在机动目标跟踪时能将误差控制在较小的范围内,具有很好的跟踪性能。     

基于直接力的着舰航迹动态逆控制仿真研究

面对舰载机人工进场着舰精确航迹控制中飞行员操纵负担重、着舰环境复杂的问题,提出采用两层并联动态逆控制框架设计基于直接升力的精确着舰航迹控制方案,具体采用控制分配处理直接升力面与常规舵面的舵效耦合和多操纵面问题,并从航迹与姿态解耦角度出发,仿真分析了所提的控制框架,证明了它在实现舰载机"魔毯"式精确着舰中的有效性,最后采用全量非线性E-2C涡桨飞机模型仿真验证控制效果可行,满足着舰航迹控制要求.     

基于IAGA的翼伞系统分段归航轨迹的优化

归航轨迹的设计和优化对实现翼伞系统的精确空投至关重要.为了实现翼伞系统的准确、安全着陆,根据翼伞系统自身的可操纵性和基本运动特性,采用经典分段归航策略.利用各段轨迹的几何关系将轨迹优化问题转化为参数优化问题,并对基本遗传算法进行了改进,运用新的改进自适应遗传算法(IAGA)进行了有效的求解.仿真试验表明:此方法是可行的...     

引入目标径向速度信息的多假设跟踪方法

提出了一种新的基于目标径向速度信息的多假设跟踪算法,来解决边搜索边跟踪雷达系统中数据互联问题,即在SB/MHT算法中,通过引入目标径向速度信息,构造新的航迹置信度公式,完善航迹启动条件。系统仿真结果证明,新算法可有效减少航迹数目,从而缩短系统计算时间,具有更强的抑制虚警的能力。     

基于Bezier和改进PSO算法的风环境下翼伞航迹规划

针对当前翼伞空投航迹规划中未考虑复杂风场影响,文中提出一种利用风场优势求解最优航迹的算法。将航迹规划问题转换成Bezier曲线的参数寻优问题,针对风场环境下可行轨迹特点提出优化策略,提出改进的粒子群优化算法求取最优解。实验结果表明,该航迹规划算法能在复杂风场环境下求出一条满足各种要求的最优航迹,算法设计合理,工程易实现。     

基于航迹隶属度的分布式系统数据融合算法

航迹关联与航迹融合是分布式目标跟踪系统数据融合的关键.本文研究了基于航迹隶属度的数据融合算法.综合各传感器航迹估计形成的目标运动状态特征向量与传感器分辨率,根据模糊聚类算法建立各观测时刻航迹隶属度矩阵与系统航迹关联决策矩阵,解决融合中心航迹关联问题.根据加权融合算法思想,结合各观测时刻航迹隶属度矩阵,实时、动态分配航迹号集合中各局部航迹权值,解决目标航迹融合问题.蒙特卡罗仿真表明,算法航迹关联效果明显优于加权航迹关联算法,并得到与简单航迹融合算法一致的目标融合航迹.     

基于跟踪状态监视的稳健航迹关联与融合算法

空间邻近目标跟踪过程中存在航迹交错现象,传统的航迹关联与融合算法可靠性大大降低。提出基于跟踪状态监视的稳健航迹关联与融合跟踪算法:首先,采用滑窗式全局最优关联方法利用多帧航迹数据确认航迹关联对,并建立系统航迹;然后,根据确认关联航迹的实时关联状态检测航迹交错;最后,根据航迹衰减残差识别运动状态,自适应选择融合量测或者融合状态估计完成系统航迹的状态更新。仿真结果表明,算法能够提高融合航迹精度,实现稳健航迹关联与融合。     

基于动态证据推理的异常航路目标检测

针对概率框架下的航迹航路相关不能有效处理低信噪比跟踪系统中存在的高冲突以及不确定性的问题,考虑到证据推理在度量、处理不确定和高冲突信息的独特优势,提出了在证据推理框架下的航路目标分类算法。为了实现对空中伪装航路目标的识别,提出了一种基于动态证据推理的航迹航路相关算法,并完成相关的仿真验证。针对低信噪比下的雷达跟踪系统进行仿真验证,结果表明,该算法实现了对航迹目标的属性识别,并有效地完成了对异常航路的目标的检测和识别。     

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.     

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.     

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.     

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.     

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.     

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.     

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.     

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.     

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.