旋转导向钻井工具姿态测量陀螺仪故障估计与处理方法

针对旋转导向钻井工具姿态测量系统陀螺仪故障问题,提出一种陀螺仪加性故障估计与处理方法.首先将陀螺仪故障增广为状态变量,融合加速度计测量信息建立非线性测量模型;然后针对由于模型线性化、陀螺仪漂移、钻井过程的高温、高压、强振动等因素导致卡尔曼滤波算法估计精度变差的问题,将测量误差等效为幅值有界但分布未知的误差,提出了一种自...     

用数字干涉仪测量变形镜影响函数的实验研究

分析了变形反射镜面形影响函数的意义，鉴于自适应光学系统中波前探测大都以测量波前斜率为基础的特点，提出应研究斜率影响函数，并在此基础上构成波前复原矩阵。还介绍了用数字干涉仪测量变形镜影响函数的方法和结果，并对测量结果进行了分析，得到了影响函数的各种参数，例如：交连值，高斯指数，特征宽度等。并将干涉法测量斜率影响函数的结果与实际的哈特探测器的测试结果进行了比较。     

Investigation of self-adaptive algebraic tomography for gas reconstruction in larger temperature range by multiple wavelengths absorption spectroscopy

We develop a self-adaptive algebraic tomography algorithm （SAATA） to investigate the simultaneons reconstruction of concentration and temperature distributions in larger temperature range from two views. The simplified optical arrangement with fewer projections is realized by extension of spectral information at multiple wavelengths, resulting in great potential in applications of practical combustion diagnosis. Tile results show SAATA can perform much better reconstructions in 300 3000 K temperature range than genetic simulated annealing algorithm and least-square orthogonal-triangular decomposition method with two- wavelength scheme. More phantoms are created to demonstrate the capability of SAATA to capture the peaks and adapt for both flat and sharp temperature distributions. Meanwhile, the advantage of high stability ensures better reconstruction performance at noise levels from 0.1% to 10% in projections.     

On Stability and Trajectory Boundedness in Mean-square Sense for ARMA Processes

Abstract For the multidimensional ARMA system A(z)y_k=C(z)w_k it is shown that stability(det A(z)≠0,z:│z│≤1)of A(z) is equivalent to the trajectory boundedness in the mean square sense(MSS)which,as a rule,is a consequence of a successful stochastic adaptive control leading the closed-loop of an ARMAXsystem to a steady state ARMA system.In comparison with existing results the stability condition imposed onC(z)is no longer needed.The only structural requirement on the system is that det A(z) and det C(z) have nounstable common factor.     

直接扩频系统自适应抗干扰技术仿真

近年由于扩频技术具有强的抗干扰能力、隐蔽性、抗多径干扰能力、精确定时和测距，并具有多址能力，所以无论在军事还是在民用方面都受到很大的关注，并且有了很大的发展。为了进一步提高扩频系统的抗干扰能力，将自适应抗干扰技术应用于扩频系统，通过计算机仿真研究了LMS算法的抗干扰性能．结果表明，LMS算法简单，可以应用于扩频系统的前端，对窄带干扰有良好的抑制．     

一种近红外光谱在线监测新方法及其在中药柱层析过程中的应用

近红外光谱(NIRS)广泛应用于生产过程分析与监测,常需事先建立定量校正或定性判别模型,并需在生产条件变化后调整模型,使用较复杂。本文从相异度和相似度两个对立互补的角度,提出自适应移动窗口标准差法和过程光谱相似度法,并以此为基础建立一种针对生产过程的无需校正模型的简易光谱在线监测方法。论文以中药柱层析过程为例,对监测过程作NIRS自适应移动窗口标准差趋势图和过程光谱相似度趋势图,并通过HPLC离线分析所得的多指标成分含量变化趋势图进行对比验证,发现可用于工艺状况实时监测,指导收集起点、终点、溶液相变点的判断,表明论文提出的方法合理可行。该方法亦可用于紫外/可见、红外、拉曼、荧光等光谱及色谱、质谱等其他过程分析技术。     

Optimization designed large-stroke MEMS micromirror for adaptive optics

A novel micromirror based on the PolyMUMPs process is designed and presented. The hexagonal micromirror with a diameter of 450 μm consists of three supporting bilayer cantilevers and a mirror plate. The bilayer cantilevers, formed with a polysilicon layer and a gold layer, elevate the mirror plate according to residual stress-induced bending. Both analytical and finite element analysis (FEA) models are built to calculate the elevated height of the free end of the cantilever. The analytical solution is in accordance with the FEA simulation results, with longitudinal stresses applied only. Results of a three-dimensional (3D) simulation with two direction stresses applied also show the elevated height to be proportional to the width of the cantilever and the length of the gold layer. Due to the torque of the joint, the elevated heights of the two kinds of cantilevers assembled with the mirror plates are much smaller than those of the free end of the cantilevers. Both micromirrors with different cantilevers are fabricated. The elevated heights of the fabricated micromirrors are measured using Veeco optical profiler, which show good coincidence with simulation results.     

波形调制多阶光盘的自适应阶次检测

波形调制多阶的时钟恢复后的读出信号跟符号序列没有对应关系,部分响应最大似然(PRML)检测不能直接使用。提出了一种基于最小欧氏距离的自适应阶次检测方法,该方法用实际波形与标准波形的欧氏距离作为阶次检测的依据。自适应调整能让设定的标准波形值向实际波形接近。保护机制能防止设定的标准波形严重偏离真实值。实验结果表明,在不调整参数的情况下,该检测方法能对不同批次盘片获得相当的阶次错误率——2×10~(-4)以下。该方法对缺陷盘片也有很好的适应性。使用该检测方法的播放系统实现了高清视频的连续稳定播放。     

能动镜中力驱动器的实现及性能测试

用于能动镜中的力驱动器采用直流电机作为驱动源,经减速器后利用滚珠丝杆传动加弹簧组件实现纳米级微位移,而采用丝杆副实现自锁。驱动器基于拉压力传感器实现闭环控制,高增益的PID控制器克服了机械摩擦的微动特性获得比较好的线性度。用4个力驱动器和3个刚性支撑组成了一个能动镜原型样机,光学干涉仪测量结果表明,力驱动器平均位移分辨力约为10nm、最大可变形量达±8μm、最大驱动力达±700N。实验结果证明了力驱动器应用于能动镜驱动器的可行性,为能动镜的实用化提供了实验依据。