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排序方式: 共有275条查询结果,搜索用时 234 毫秒
81.
82.
基于Rudin-Osher-Fatemi模型的图像除模糊和除噪音新模型 总被引:1,自引:0,他引:1
介绍一种依赖时间的新模型来解决图像除噪音和除模糊问题.分别使用逆反射、中值两种边界条件的数值试验比较本文新模型和Rudin-Osher-Fatemi模型.试验结果表明中值边界条件的误差比逆反射边界条件误差小. 相似文献
83.
The optic-bound effect on fibre optic gyro (FOG) precision is
analysed theoretically, and formulas describing the change of FOG
light power under the action of optic-bound effect are given. It is
confirmed that optic-bound effect is a main instantaneous
non-reciprocity effect of FOG in addition to the Sagnac effect and
can lead to a dynamic error of FOG in practical environments. An
approach to suppressing or eliminating the error due to the
optic-bound effect is presented and verified experimentally. The
result shows that the approach is valid and the precision of FOG is
improved observably. 相似文献
84.
Stochastic resonance (SR) is based on the cooperative effect between
the stochastic dynamical system and the external forcing. As is well
known, the cooperative effect is produced by adding noises. In this
paper, we show the evidence that by changing the system parameters
and the signal intensity, a nonlinear system in the presence of an
input aperiodic signal can yield the cooperative effect, with the
noise fixed. To quantify the nonlinear system output, we determine
the theoretical bit error rate (BER). By numerical simulation, the
validity of the theoretical derivation is checked. Besides, we show
that parameter-induced SR is more realizable than SR via adding
noises, especially when the noise intensity exceeds the resonance
level, or when the characteristic of the noise is not known. 相似文献
85.
HAN Yin-Xia LI Jing-Hui CHEN Shi-Gang 《理论物理通讯》2005,44(3):426-430
Stochastic resonance (SR) phenomenon of the system that is subject to the asymmetric two-state noise is investigated from the broad sense. It is shown that the amplitudes of the output signal exhibit the non-monotonic dependence on the input signal frequency w, and the parameters describing the asymmetric two-state noise, such as the transition rate A, the order parameter k describing the asymmetric degree of the two-state noise, and the noise strength D. 相似文献
86.
LI Tai-Quan DONG Ping YANG Hong-Quan HAN Li-Bo 《理论物理通讯》2005,44(2):288-292
Defining the quantity K as the signal-to-noise ratio (SNR) and the normalized intensity fluctuation C(O) of a single-mode laser for bias signal modulation driven by color noises with colored correlation, the whole output properties of the laser system is described by K. It is found that there is a maximum in the curves of K versus D, Q, and io. The optimization parameters are gained. 相似文献
87.
何军 《应用数学和力学(英文版)》2009,30(2):255-262
An approximate method is presented for obtaining analytical solutions for the conditional first passage probability of systems under modulated white noise excitation. As the method is based on VanMarcke's approximation, with normalization of the response introduced, the expected decay rates can be evaluated from the second-moment statistics instead of the correlation functions or spectrum density functions of the response of considered structures. Explicit solutions to the second-moment statistics of the response are given. Accuracy, efficiency and usage of the proposed method are demonstrated by the first passage analysis of single-degree-of-freedom (SDOF) linear systems under two special types of modulated white noise excitations. 相似文献
88.
The paper not only studies the noise reduction methods of chaotic time series with noise and its reconstruction techniques,but also discusses prediction techniques of chaotic time series and its applications based on chaotic data noise reduction.In the paper,we first decompose the phase space of chaotic time series to range space and null noise space.Secondly we restructure original chaotic time series in range space.Lastly on the basis of the above,we establish order of the nonlinear model and make use of the nonlinear model to predict some research.The result indicates that the nonlinear model has very strong ability of approximation function,and Chaos predict method has certain tutorial significance to the practical problems. 相似文献
89.
90.
为了有效消除光源抖动及系统不稳定因素给光纤传感器带来的噪音干扰,提高光纤传感器的准确度,本文提出了一种基于光子晶体光纤长周期光栅的差分算法.利用光子晶体光纤长周期光栅良好的温度稳定性及宽光谱滤波特性,同时监测位于光子晶体光纤长周期光栅透射谱正负斜率线性区域内的两个信号功率变化.这两个信号是经同一路径到监测设备的,包含光源抖动以及系统其它不稳定因素带来的噪音干扰,对这两个信号进行差分处理即可有效消除噪音干扰,并将其应用于光纤环镜温度传感器.结果表明:通过基于光子晶体光纤长周期光栅的差分处理,在光源功率变化±10%的情况下,差分值基本保持不变,由此获得的温度测量值与真实值相对误差分别为0.04和0.03|与未引入差分算法相比,传感器准确度从约76%提高到约97%.本文提出的基于光子晶体光纤长周期光栅的差分算法可以有效消除光纤传感器内功率抖动所带来的噪音干扰,大大提高系统的准确度. 相似文献