随着武器技术的不断发展,常规弹药的制导化改造已成为一种必然趋势。通过应用精确制导技术,可以显著提高弹药的打击精度和效率。而在实现弹药制导化改造的过程中,精准测量角速度是一项关键核心技术。微机电系统(Micro-Electro Mechanica...随着武器技术的不断发展,常规弹药的制导化改造已成为一种必然趋势。通过应用精确制导技术,可以显著提高弹药的打击精度和效率。而在实现弹药制导化改造的过程中,精准测量角速度是一项关键核心技术。微机电系统(Micro-Electro Mechanical System,MEMS)陀螺仪存在输出信号噪声大、精度低的问题,针对上述问题,提出了一种自适应噪声完备集合鲁棒局部均值分解(CERLMDAN)和归一化LMS算法(Normalized Least Mean Square,NLMS)结合的滤波模型。该模型通过在鲁棒局部均值分解(Robust Local Mean Decomposition,RLMD)过程中添加白噪声将原始数据分解为多个乘积函数(Product Functions,PF),并根据排列熵(Permutation Entropy,PE)将PF分为混合PF和有用PF;其次对混合PF使用NLMS去噪;最后,把处理后的PF和有用PF进行重构,得到去噪后的信号。试验表明,本文提出的去噪模型对信号均值与方差有显著提升,信号均值由0.5891提升至0.5396,信号方差由44.473提升至5.2692。展开更多
针对大地测量型GNSS接收机获取的信噪比(Signal to Noise Ratio,SNR)观测值存在趋势项分离不佳和信号叠加干涉的问题,融合自适应噪声完备集合鲁棒局部均值分解方法对原始SNR信号进行分解,有效分离SNR观测值中的趋势项并提取相应的潮位信...针对大地测量型GNSS接收机获取的信噪比(Signal to Noise Ratio,SNR)观测值存在趋势项分离不佳和信号叠加干涉的问题,融合自适应噪声完备集合鲁棒局部均值分解方法对原始SNR信号进行分解,有效分离SNR观测值中的趋势项并提取相应的潮位信号,以布设在美国华盛顿州星期五海港岸边的SC02测站为例,利用实测数据反演潮位变化并与传统的低阶多项式拟合方法进行对比分析。结果表明,融合CERLMDAN方法的反演结果的均方根误差(Root Mean Square Error,RMSE)、相关系数分别为0.56 m和0.97,相比于传统方法的反演精度提升了33.7%。展开更多
Nonlocal means filtering is a noise attenuation method based on redundancies in image information. It is also a nonlocal denoising method that uses the self-similarity of an image, assuming that the valid structures o...Nonlocal means filtering is a noise attenuation method based on redundancies in image information. It is also a nonlocal denoising method that uses the self-similarity of an image, assuming that the valid structures of the image have a certain degree of repeatability that the random noise lacks. In this paper, we use nonlocal means filtering in seismic random noise suppression. To overcome the problems caused by expensive computational costs and improper filter parameters, this paper proposes a block-wise implementation of the nonlocal means method with adaptive filter parameter estimation. Tests with synthetic data and real 2D post-stack seismic data demonstrate that the proposed algorithm better preserves valid seismic information and has a higher accuracy when compared with traditional seismic denoising methods （e.g., f-x deconvolution）, which is important for subsequent seismic processing and interpretation.展开更多
For random noise suppression of seismic data, we present a non-local Bayes （NL- Bayes） filtering algorithm. The NL-Bayes algorithm uses the Gaussian model instead of the weighted average of all similar patches in th...For random noise suppression of seismic data, we present a non-local Bayes （NL- Bayes） filtering algorithm. The NL-Bayes algorithm uses the Gaussian model instead of the weighted average of all similar patches in the NL-means algorithm to reduce the fuzzy of structural details, thereby improving the denoising performance. In the denoising process of seismic data, the size and the number of patches in the Gaussian model are adaptively calculated according to the standard deviation of noise. The NL-Bayes algorithm requires two iterations to complete seismic data denoising, but the second iteration makes use of denoised seismic data from the first iteration to calculate the better mean and covariance of the patch Gaussian model for improving the similarity of patches and achieving the purpose of denoising. Tests with synthetic and real data sets demonstrate that the NL-Bayes algorithm can effectively improve the SNR and preserve the fidelity of seismic data.展开更多
In this paper, an adaptive noise detection and removal algorithm using local statistics for salt-and-pepper noise are proposed. In order to determine constraints for noise detection, the local mean, varianoe, and maxi...In this paper, an adaptive noise detection and removal algorithm using local statistics for salt-and-pepper noise are proposed. In order to determine constraints for noise detection, the local mean, varianoe, and maximum value are used. In addition, a weighted median filter is employed to remove the detected noise. The simulation results show the capability of the proposed algorithm removes the noise effectively.展开更多
Objectives To evaluate the effects of white noise on pain-related cortical response,pain score,and behavioral and physiological parameters in neonates with procedural pain.Methods A double-blind,randomized controlled ...Objectives To evaluate the effects of white noise on pain-related cortical response,pain score,and behavioral and physiological parameters in neonates with procedural pain.Methods A double-blind,randomized controlled trial was conducted.Sixty-six neonates from the Neonatal Intensive Care Unit in a university-affiliated general hospital were randomly assigned to listen to white noise at 50 dB(experimental group)or 0 dB(control group)2 min before radial artery blood sampling and continued until 5 min after needle withdrawal.Pain-related cortical response was measured by regional cerebral oxygen saturation(rScO_(2))monitored with near-infrared spectroscopy,and facial expressions and physiological parameters were recorded by two video cameras.Two assessors scored the Premature Infant Pain Profile-Revised(PIPP-R)independently when viewing the videos.Primary outcomes were pain score and rScO_(2)during arterial puncture and 5 min after needle withdrawal.Secondary outcomes were pulse oximetric oxygen saturation(SpO_(2))and heart rate(HR)during arterial puncture,and duration of painful expressions.The study was registered at the Chinese Clinical Trial Registry(ChiCTR2200055571).Results Sixty neonates(experimental group,n=29;control group,n=31)were included in the final analysis.The maximum PIPP-R score in the experimental and control groups was 12.00(9.50,13.00),12.50(10.50,13.75),respectively(median difference−0.5,95%CI−2.0 to 0.5),and minimum rScO_(2)was(61.22±3.07)%,(61.32±2.79)%,respectively(mean difference−0.325,95%CI−1.382 to 0.732),without significant differences.During arterial puncture,the mean rScO_(2),HR,and SpO_(2)did not differ between groups.After needle withdrawal,the trends for rScO_(2),PIPP-R score,and facial expression returning to baseline were different between the two groups without statistical significance.Conclusion The white noise intervention did not show beneficial effects on pain-related cortical response as well as pain score,behavioral and physiological parameters in neonates with procedural pain.展开更多
文摘随着武器技术的不断发展,常规弹药的制导化改造已成为一种必然趋势。通过应用精确制导技术,可以显著提高弹药的打击精度和效率。而在实现弹药制导化改造的过程中,精准测量角速度是一项关键核心技术。微机电系统(Micro-Electro Mechanical System,MEMS)陀螺仪存在输出信号噪声大、精度低的问题,针对上述问题,提出了一种自适应噪声完备集合鲁棒局部均值分解(CERLMDAN)和归一化LMS算法(Normalized Least Mean Square,NLMS)结合的滤波模型。该模型通过在鲁棒局部均值分解(Robust Local Mean Decomposition,RLMD)过程中添加白噪声将原始数据分解为多个乘积函数(Product Functions,PF),并根据排列熵(Permutation Entropy,PE)将PF分为混合PF和有用PF;其次对混合PF使用NLMS去噪;最后,把处理后的PF和有用PF进行重构,得到去噪后的信号。试验表明,本文提出的去噪模型对信号均值与方差有显著提升,信号均值由0.5891提升至0.5396,信号方差由44.473提升至5.2692。
文摘针对大地测量型GNSS接收机获取的信噪比(Signal to Noise Ratio,SNR)观测值存在趋势项分离不佳和信号叠加干涉的问题,融合自适应噪声完备集合鲁棒局部均值分解方法对原始SNR信号进行分解,有效分离SNR观测值中的趋势项并提取相应的潮位信号,以布设在美国华盛顿州星期五海港岸边的SC02测站为例,利用实测数据反演潮位变化并与传统的低阶多项式拟合方法进行对比分析。结果表明,融合CERLMDAN方法的反演结果的均方根误差(Root Mean Square Error,RMSE)、相关系数分别为0.56 m和0.97,相比于传统方法的反演精度提升了33.7%。
基金supported by the National Natural Science Foundation of China(No.41074075)National Science and Technology Project(SinoProbe-03)+1 种基金National public industry special subject(No. 201011047-02)Graduate Innovation Fund of Jilin University(No. 20121070)
文摘Nonlocal means filtering is a noise attenuation method based on redundancies in image information. It is also a nonlocal denoising method that uses the self-similarity of an image, assuming that the valid structures of the image have a certain degree of repeatability that the random noise lacks. In this paper, we use nonlocal means filtering in seismic random noise suppression. To overcome the problems caused by expensive computational costs and improper filter parameters, this paper proposes a block-wise implementation of the nonlocal means method with adaptive filter parameter estimation. Tests with synthetic data and real 2D post-stack seismic data demonstrate that the proposed algorithm better preserves valid seismic information and has a higher accuracy when compared with traditional seismic denoising methods （e.g., f-x deconvolution）, which is important for subsequent seismic processing and interpretation.
基金financially sponsored by Research Institute of Petroleum Exploration&Development(PETROCHINA)Scientific Research And Technology Development Projects(No.2016ycq02)China National Petroleum Corporation Science&Technology Development Projects(No.2015B-3712)Ministry of National Science&Technique(No.2016ZX05007-006)
文摘For random noise suppression of seismic data, we present a non-local Bayes （NL- Bayes） filtering algorithm. The NL-Bayes algorithm uses the Gaussian model instead of the weighted average of all similar patches in the NL-means algorithm to reduce the fuzzy of structural details, thereby improving the denoising performance. In the denoising process of seismic data, the size and the number of patches in the Gaussian model are adaptively calculated according to the standard deviation of noise. The NL-Bayes algorithm requires two iterations to complete seismic data denoising, but the second iteration makes use of denoised seismic data from the first iteration to calculate the better mean and covariance of the patch Gaussian model for improving the similarity of patches and achieving the purpose of denoising. Tests with synthetic and real data sets demonstrate that the NL-Bayes algorithm can effectively improve the SNR and preserve the fidelity of seismic data.
基金supported by the Korea Science and Engineering Foundation(KOSEF)granted bythe Korea government(MEST)(No.2009-0079776)
文摘In this paper, an adaptive noise detection and removal algorithm using local statistics for salt-and-pepper noise are proposed. In order to determine constraints for noise detection, the local mean, varianoe, and maximum value are used. In addition, a weighted median filter is employed to remove the detected noise. The simulation results show the capability of the proposed algorithm removes the noise effectively.
基金This work was supported by grants from Guangdong Nurse Association[gdshsxh2021a058]Department of Science and Technology of Guangdong Province[2014A020212396].
文摘Objectives To evaluate the effects of white noise on pain-related cortical response,pain score,and behavioral and physiological parameters in neonates with procedural pain.Methods A double-blind,randomized controlled trial was conducted.Sixty-six neonates from the Neonatal Intensive Care Unit in a university-affiliated general hospital were randomly assigned to listen to white noise at 50 dB(experimental group)or 0 dB(control group)2 min before radial artery blood sampling and continued until 5 min after needle withdrawal.Pain-related cortical response was measured by regional cerebral oxygen saturation(rScO_(2))monitored with near-infrared spectroscopy,and facial expressions and physiological parameters were recorded by two video cameras.Two assessors scored the Premature Infant Pain Profile-Revised(PIPP-R)independently when viewing the videos.Primary outcomes were pain score and rScO_(2)during arterial puncture and 5 min after needle withdrawal.Secondary outcomes were pulse oximetric oxygen saturation(SpO_(2))and heart rate(HR)during arterial puncture,and duration of painful expressions.The study was registered at the Chinese Clinical Trial Registry(ChiCTR2200055571).Results Sixty neonates(experimental group,n=29;control group,n=31)were included in the final analysis.The maximum PIPP-R score in the experimental and control groups was 12.00(9.50,13.00),12.50(10.50,13.75),respectively(median difference−0.5,95%CI−2.0 to 0.5),and minimum rScO_(2)was(61.22±3.07)%,(61.32±2.79)%,respectively(mean difference−0.325,95%CI−1.382 to 0.732),without significant differences.During arterial puncture,the mean rScO_(2),HR,and SpO_(2)did not differ between groups.After needle withdrawal,the trends for rScO_(2),PIPP-R score,and facial expression returning to baseline were different between the two groups without statistical significance.Conclusion The white noise intervention did not show beneficial effects on pain-related cortical response as well as pain score,behavioral and physiological parameters in neonates with procedural pain.
