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高精度长光栅动态光刻机定位误差校正 总被引:1,自引:0,他引:1
本文介绍了一种采用微机对高精度长光栅动态光刻机定位误差进行实时校正的方法,提出了空间域脉冲增减法误差校正原理,设计了误差校正电路和校正软件。该方法可从空间域同时校正定位信号误差和温度误差,校正精度较高。实验结果表明该方法是可行的,该方法的提出为研制高精度长光栅提供了一条新的途径。 相似文献
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《Journal of Microcomputer Applications》1994,17(3):255-271
In this paper a statistical approach to error location and correction for data stored in secondary memories is developed. The approach is based on the observation that the data records in secondary storage have some inherent redundancy of information. This redundancy cannot precisely be predicted as in the case of typical error correction scheme's artificial redundancy. However, the redundancy can be exploited to provide error correction with some degree of confidence. We use simple and weighted checksum schemes for error detection and present algorithms for single and multiple error correction using statistical error location and correction (SELAC). An implementation of SELAC will be described with an elaborate study of its error-correction capabilities. A conspicuous aspect of SELAC is that it will not cost any processor time and storage overhead until after an error is encountered, unlike the classical schemes using single error correcting-double error detecting (SEC-DED) and double error correcting-triple error detecting (DEC-TED) codes. 相似文献
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梁玮 《计算技术与自动化》2020,39(2):155-159
针对传统英语发音学习过程中存在的发音不准确、缺乏发音评价和纠错指导的现状。提出了基于Android平台开发一款发音跟读、发音比对、发音评分和纠错多功能应用的英语发音训练系统。基于短时过零率端点检测进行语音预处理,获得较为稳定的语音段信号,利用美尔倒普系数(MFCC)提取语音信号特征值,获得每帧语音频谱特性。通过矢量间距离计算表征信号的匹配度,在自适应(AP)评价法来实现平均匹配距离与发音评分间的逻辑关系,得到发音共振峰包络图,利用生成的发音共振峰对比图构建发音共振峰和读音口型模型进行发音跟读质量反馈。实际应用结果表明:开发的系统应用能够准确进行定性化的发音口型纠正,有效满足现代英语学习过程中的智能化、实时性和便携化需求。 相似文献
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The servo tracks of hard disk drives are written at the time of manufacture with the equipment of servo track writer. The disk vibrations or head fluctuations during servo track writing process give rise to servo track writing error. The servo track writing error may cause some critical errors during data writing operation. In this paper, we propose a new correction algorithm for the servo track writing error based on the iterative learning control technique. The estimate of the servo track writing error is constructed from the position error signal and updated iteratively at each disk rotation. Then, the estimate of servo track writing error is used to correct the position error signal in a feed-forward manner. Our correction algorithm is robust to system model uncertainties, computationally quite simple, and has fast convergence rate. Furthermore, we give a rigorous analysis for the convergence of our correction algorithm. In order to demonstrate the practical use of our work, we present some experimental results using a commercially available hard disk drive. 相似文献
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杯形波动陀螺具有极高的Q值,一般都在20 000以上,因此仅仅0.3‰的驱动信号频率误差都会使陀螺机械灵敏度降低99%以上。针对这一问题实现了一种基于直接数字频率合成的高性能正弦信号生成算法,以此为基础从统计域的角度对引起频率源抖动的根源进行了估计分析,并给出了一种具有针对性的抖动分离方法,为频率源的设计提供了理论指导和依据,降低了修正和优化频率源的盲目性。由阿伦方差可知采用抖动分离方法优化后,频率源短期稳定度提高约为20%。通过对设计的频率源进行一系列时域和频域测试分析,证明最终的驱动信号频率稳定在1 mHz以内。 相似文献
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Hyun Jae Kang Sang Hyun Kim Seung-Hi Lee Chung Choo Chung 《Microsystem Technologies》2012,18(9-10):1247-1253
An adaptive digital demodulation method for a sinusoidal encoder signal is proposed for fast and accurate analysis of spiral servo track writing (SSTW). The proposed methods combine adaptive signal correction and digital interpolation. In addition, digital phase-shifted sinusoid (PSS) interpolation is proposed in order to acquire precise position information. The adaptive signal correction method compensates for a fast-motion non-ideal encoder signal. The digital PSS can be simply implemented and can resolve the switching noise of conventional analog methods. The proposed adaptive digital demodulation scheme can be simply digitalized and can improve the position control in SSTW. From the simulation and experimental results, we have validated the proposed methods, which show noticeable improvement in terms of the Lissajous error and the position error signal. 相似文献
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提出通过遥测加速度振动信号时域数值积分和最小二乘相结合的方法消除零漂对积分结果精度的影响,即采用最小二乘原则对加速度振动信号时域数值积分结果根据其包含的趋势项形式进行多项式拟合,获得修正参数,进一步对积分结果进行修正,获取遥测速度和位移振动信号的修正值。方法在仿真信号上进行了应用,修正结果和真实结果的误差较小,结果精度较高,说明方法的有效性,在此基础上将方法在遥测加速度振动信号的处理上进行了应用,鉴于方法模型的在仿真信号上的有效性,可以推断获取的遥测速度和位移振动信号的修正结果具有较高的置信度。 相似文献
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To improve the performances of the wireless mobile communication system, a statistical method is illustrated in this paper. It consists in separating the signals at the reception of communication systems based on code division multiple access technology. The idea is to optimize the separation of the various users sharing the same frequency and temporal resources using the emergent statistical method of independent component analysis (ICA). ICA makes it possible to extract emitted signals that are as statistically independent as possible. The bit error rate and the signal to noise ratio are used as criteria for evaluating the performances of the ICA receiver. Adding white Gaussian noise to the input signal channel and the Rayleigh channel (fading channel) cases has been considered. A comparative study with conventional receivers such as the RAKE, the matched filter (MF), and the minimum mean-squared error is carried out. The obtained results show the superiority of an ICA receiver compared to an MF receiver. 相似文献
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针对光电制导导弹高精度指向需求,通过研究导弹校靶方法以修正系统误差,提升光电导引头指向精度;提出解析法和几何法两种校靶方法,解析法是从数学推导的角度出发,利用坐标等效变换列写方程组,通过求解多元方程组获得校靶修正角度;几何法是从距离逼近的角度出发,通过多点测量实际指向误差,利用最小二乘、几何旋转变换等方法得到校靶修正角度;最后利用数字仿真分别模拟了两种校靶算法,并进行了对比分析,验证了两种算法的有效性. 相似文献
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针对原有桥梁检测仪器误差矫正方法数据矫正精度较差的问题,设计基于激光线扫描的桥梁检测仪器误差自动化矫正方法。设定激光扫描仪参数并应用其完成误差数据的捕捉与处理,应用模糊C均值算法得出误差值的变化区间,结合马尔科夫链构建桥梁检测仪器误差矫正模型,完成检测数据矫正。引用Excel VBA程序实现桥梁检测仪器误差自动化矫正,设定数据库数据项格式,保证数据精度。至此,基于激光线扫描的桥梁检测仪器误差自动化矫正方法设计完成。设计对比实验,制定实验流程,选定实验测试点获取实验结果。与原有方法相比,此方法数据矫正精度较高且精度波动较小。由此可知,此方法优于原有方法,将其应用可有效降低桥梁检测误差的产生。 相似文献
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对扫描探针显微镜中的单管压电执行器在x—y平面扫描的电压一位移特性进行了物理和数据分析,提出了一种基于采集数据和Matlab数值计算的建模方法。经过大量的实验数据的统计分析,充分考虑了扫描速度、扫描角度、非正交和耦合误差因素对单管压电扫描器模型误差的影响,建立的模型的数学表达式在形式上表现为二项式叠加各种误差表达式。基于此模型推导出了单管压电扫描器的非线性校正的数学表达式,通过计算机仿真软件Matlab对其进行了仿真研究。仿真实验证明建立的模型能有效的消除各种误差。该方法避免了建模时对压电陶瓷内部机理(极化等)的分析,使模型参数的个数降低到很少,是一种在工程实践中非常实用的建模方法。 相似文献
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飞机机翼垂尾壁板制孔系统孔位容易受到随机波动干扰产生误差,提出基于电控机械式误差调节的飞机机翼垂尾壁板制孔系统孔位自动校正方法,构建飞机机翼垂尾壁板制孔系统孔位校正的执行机构控制模型,采用位移传感器进行垂尾壁板制孔系统孔位的误差偏移测量,在执行机构中进行误差的自适应调节和输出稳定性控制,结合迭代学习控制方法进行飞机机翼垂尾壁板制孔系统孔位自动校正过程中的误差偏移修正,采用电控式的机械误差调节方法,实现机翼垂尾壁板制孔系统孔位自动校正优化。仿真结果表明,采用该方法进行机翼垂尾壁板制孔系统孔位校正的自动性较好,误差修正能力极强,提高了飞机机翼垂尾壁板制孔系统孔位主动调节和误差自适应修正性能。 相似文献
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在工业现场,角位移传感器校准受特殊条件的限制,很难用标准器进行密集误差采样来提高精度。针对该问题提出了一种稀疏误差采样及补偿方法。在分析时栅角位移传感器的感应信号的基础上,提出稀疏采样第1个对极内细分误差+对极点零位误差的测补方式,给出用激光干涉仪获取零位和细分误差的方法及采用稀疏采样的误差补偿模型进行补偿的具体过程。以72对极时栅角位移传感器为对象进行研究,实验结果表明:该方法充分剔除了零位误差且补偿了细分误差,在稀疏采样的条件下即可实现整周范围的有效补偿,大大提高了修正效率和测量精度,时栅传感器的精度达到2.69″。 相似文献