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Research on fiber optic gyro signal de-noising based on wavelet packet soft-threshold 被引量:7
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作者 Qian Huaming & Ma Jichen Coll.of Automation,Harbin Engineering Univ.,Harbin 150001,P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期607-612,共6页
Gyro's drift is not only the main drift error which influences gyro's precision but also the primary factor that affects gyro's reliability. Reducing zero drift and random drift is a key problem to the output of a ... Gyro's drift is not only the main drift error which influences gyro's precision but also the primary factor that affects gyro's reliability. Reducing zero drift and random drift is a key problem to the output of a gyro signal. A three-layer de-nosing threshold algorithm is proposed based on the wavelet decomposition to dispose the signal which is collected from a running fiber optic gyro (FOG). The coefficients are obtained from the three-layer wavelet packet decomposition. By setting the high frequency part which is greater than wavelet packet threshold as zero, then reconstructing the nodes which have been filtered out noise and interruption, the soft threshold function is constructed by the coefficients of the third nodes. Compared wavelet packet de-noise with forced de-noising method, the proposed method is more effective. Simulation results show that the random drift compensation is enhanced by 13.1%, and reduces zero drift by 0.052 6°/h. 展开更多
关键词 wavelet transform DRIFT fiber optic gyro soft-threshold signal de-noising
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Moving horizon based wavelet de-noising method of dual-observed geomagnetic signal for nonlinear high spin projectile roll positioning 被引量:3
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作者 Ting-ting Yin Fang-xiu Jia Xiao-ming Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第2期417-424,共8页
Phase-frequency characte ristics of approximate sinusoidal geomagnetic signals can be used fo r projectile roll positioning and other high-precision trajectory correction applications.The sinusoidal geomagnetic signal... Phase-frequency characte ristics of approximate sinusoidal geomagnetic signals can be used fo r projectile roll positioning and other high-precision trajectory correction applications.The sinusoidal geomagnetic signal deforms in the exposed and magnetically contaminated environment.In order to preciously recognize the roll information and effectively separate the noise component from the original geomagnetic sequence,based on the error source analysis,we propose a moving horizon based wavelet de-noising method for the dual-observed geomagnetic signal filtering where the captured rough roll frequency value provides reasonable wavelet decomposition and reconstruction level selection basis for sampled sequence;a moving horizon window guarantees real-time performance and non-cumulative calculation amount.The complete geomagnetic data in full ballistic range and three intercepted paragraphs are used for performance assessment.The positioning performance of the moving horizon wavelet de-noising method is compared with the band-pass filter.The results show that both noise reduction techniques improve the positioning accuracy while the wavelet de-noising method is always better than the band-pass filter.These results suggest that the proposed moving horizon based wavelet de-noising method of the dual-observed geomagnetic signal is more applicable for various launch conditions with better positioning performance. 展开更多
关键词 High-spin PROJECTILE ROLL POSITIONING Dual-observed GEOMAGNETIC signal WAVELET de-noising Discrete WAVELET transform
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Application and prospects of proteomic technology in inflammation:a review
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作者 Senye Wang Yanhai Chu +4 位作者 Jiajia Yuan Yiqi Li Zhenhua Liu Xiaoyu Chen Wenyi Kang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2373-2385,共13页
Proteomics is a new technology that has been widely applied in the field of life and health science.It effectively addresses issues related to the impact of dietary structure on organs,tissues,and cells,as well as the... Proteomics is a new technology that has been widely applied in the field of life and health science.It effectively addresses issues related to the impact of dietary structure on organs,tissues,and cells,as well as the changes in proteins in various organs,tissues,and cells under disease conditions.The differential proteins identified through proteomics can serve as disease biomarkers and target proteins affecting health and can be used for disease diagnosis and health regulation.In this paper,the application of proteomics in the field of infl ammation in recent years was summarized,especially in the therapeutic target and mechanism of action,which opens up a new way for more effective prevention,diagnosis,and treatment of inflammation,and provides medical protection for human life and health. 展开更多
关键词 Proteomics technology INFLAMMATION Biomarkers Potential target signaling pathway
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Automatic de-noising and recognition algorithm for drilling fluid pulse signal 被引量:1
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作者 HU Yongjian HUANG Yanfu LI Xianyi 《Petroleum Exploration and Development》 2019年第2期393-400,共8页
Wavelet forced de-noising algorithm is suitable for denoising of unsteady drilling fluid pulse signal, including baseline drift rectification and two-stage de-noising processing of frame synchronization signal and ins... Wavelet forced de-noising algorithm is suitable for denoising of unsteady drilling fluid pulse signal, including baseline drift rectification and two-stage de-noising processing of frame synchronization signal and instruction signal. Two-stage de-noising processing can reduce the impact of baseline drift and determine automatic peak detection threshold range for signal recognition by distinguishing different features of frame synchronization pulse and instruction pulse. Rising and falling edge relative protruding threshold is defined for peak detection in signal recognition, which can make full use of the degree of the signal peak change and detect peaks flexibly with rising and falling edge relative protruding threshold combination. A synchronous decoding method was designed to reduce position uncertainty of the frame synchronization pulse and eliminate the accumulative error of time base drift, which determines the first instruction pulse position according to position of the frame synchronization pulse and decodes subsequent instruction pulse by taking current instruction pulse as new bit synchronization pulse. Special tool software was developed to tune algorithm parameters, which has a decoding success rate of about 95% for the universal coded signals. For the special coded signals with check byte, decoding success rate using the automatic threshold adjustment algorithm is as high as 99%. 展开更多
关键词 drilling fluid pulse signal signal processing DECODING SUCCESS rate AUTOMATIC de-noising and recognition wavelet FORCED de-noising peak detection synchronous DECODING
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Implementation of GPR Signals De-Noising Based on DSP
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作者 CHEN Xiao-li TIAN Mao ZHOU Hui-lin 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第6期1005-1008,共4页
An important issue of ground-penetrating radar (GPR) signals analysis is de-noising thai is the guarantee of acquiring good detecting effect. The paper illustrates a successful application of digital single process... An important issue of ground-penetrating radar (GPR) signals analysis is de-noising thai is the guarantee of acquiring good detecting effect. The paper illustrates a successful application of digital single processor (DSP) based on wavelet shrinkage algorithm. In order to realize real-time GPP, signals analysis, some key issues are discussed such as the realization of fast wavelet transformation, the selection of CPU chip and the optimization of data movement. Experimenial results show that the DSP based application not only basically meets the real-time requirement of GPP, signals analysis, but also assures the quality of the GPR signals analysis. 展开更多
关键词 wavelet shrinkage de-noising GPR digital signal processor real time soft thresholding SNR
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Prediction of Traffic Volume of Motor Vehicles Based on Mobile Phone Signaling Technology
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作者 Jin Shang Hailong Su +2 位作者 Kai Hu Xin Guo Defa Sun 《Computers, Materials & Continua》 SCIE EI 2023年第4期799-814,共16页
Urban traffic volume detection is an essential part of trafficplanning in terms of urban planning in China. To improve the statisticsefficiency of road traffic volume, this thesis proposes a method for predictingmotor... Urban traffic volume detection is an essential part of trafficplanning in terms of urban planning in China. To improve the statisticsefficiency of road traffic volume, this thesis proposes a method for predictingmotor vehicle traffic volume on urban roads in small and medium-sizedcities during the traffic peak hour by using mobile signal technology. Themethod is verified through simulation experiments, and the limitations andthe improvement methods are discussed. This research can be divided intothree parts: Firstly, the traffic patterns of small and medium-sized cities areobtained through a questionnaire survey. A total of 19745 residents weresurveyed in Luohe, a medium-sized city in China and five travel modes oflocal people were obtained. Secondly, after the characteristics of residents’rest and working time are investigated, a method is proposed in this studyfor the distribution of urban residential and working places based on mobilephone signaling technology. Finally, methods for predicting traffic volume ofthese travel modes are proposed after the characteristics of these travel modesand methods for the distribution of urban residential and working placesare analyzed. Based on the actual traffic volume data observed at offlineintersections, the project team takes Luohe city as the research object and itverifies the accuracy of the prediction method by comparing the predictiondata. The prediction simulation results of traffic volume show that the averageerror rate of traffic volume is unstable. The error rate ranges from 10% to 30%.In this thesis, simulation experiments and field investigations are adopted toanalyze why these errors occur. 展开更多
关键词 Traffic planning prediction of traffic volume mobile phone signaling technology small and medium-sized cities traffic peak hour
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Signal Processing Circuit Design of Infrared Detection System with SO2 Concentration Based on Correlation Filter Technology
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作者 赵雁雨 姚娜 《Journal of Measurement Science and Instrumentation》 CAS 2011年第4期394-397,共4页
Signals from infrared detector are very weak in SO2 concentration measuring system.In order to improve the sensitivity of detection,combining with filter correlation technology and infrared absorption principle,the we... Signals from infrared detector are very weak in SO2 concentration measuring system.In order to improve the sensitivity of detection,combining with filter correlation technology and infrared absorption principle,the weak signal processing circuit is designed according to correlation detection technology.Under laboratory conditions,system performance of SO2 concentration is tested,and the experimental data are analyzed and processed.Then relationship of SO2 concentration and the measuring voltage is provided to prove that the design improves measuring sensitivity of the system. 展开更多
关键词 SO2 infrared absorption correlation detecting and filtering technology weak signal processing
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A De-Noising Method for Track State Detection Signal Based on EMD
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作者 Liming Li Xiaodong Chai +1 位作者 Shubin Zheng Wenfa Zhu 《Journal of Signal and Information Processing》 2014年第4期104-111,共8页
In the track irregularity detection, the acceleration signals of the inertial measurement unit (IMU) output which with low frequency components and noise, this paper studied a de-noising algorithm. Based on the criter... In the track irregularity detection, the acceleration signals of the inertial measurement unit (IMU) output which with low frequency components and noise, this paper studied a de-noising algorithm. Based on the criterion of consecutive mean square error, a de-noising method for IMU acceleration signals based on empirical mode decomposition (EMD) was proposed. This method can divide the intrinsic mode functions (IMFs) derived from EMD into signal dominant modes and noise dominant modes, then the modes reflecting the important structures of a signal were combined together to form partially reconstructed de-noised signal. Simulations were conducted for simulated signals and a real IMU acceleration signals using this method. Experimental results indicate that this method can efficiently and adaptively remove noise, and this method can better meet the precision requirement. 展开更多
关键词 TRACK IRREGULARITY signal de-noising Empirical Mode Decomposition Consecutive Mean SQUARE Error
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De-Noising of ECG Signals by Design of an Optimized Wavelet
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作者 Vahid Makhdoomi Kaviri Masoud Sabaghi Saeid Marjani 《Circuits and Systems》 2016年第11期3746-3755,共10页
In this paper, a different method for de-noising of ECG signals using wavelets is presented. In this strategy, we will try to design the best wavelet for de-nosing. Genetic algorithm tests wide range of quadrature fil... In this paper, a different method for de-noising of ECG signals using wavelets is presented. In this strategy, we will try to design the best wavelet for de-nosing. Genetic algorithm tests wide range of quadrature filter banks and the best of them will be chosen that minimize the Signal-to-Noise Ratio (SNR). Furthermore, the wavelet function and scaling function related to these filters are reported as the best wavelet for de-noising. Simulation results for de-noising of a noisy ECG signal show that using obtained wavelet by proposed method improves the SNR of about 2.5 dB. 展开更多
关键词 WAVELETS de-noising Genetic Algorithm ECG signals
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A NEW DE-NOISING METHOD BASED ON 3-BAND WAVELET AND NONPARAMETRIC ADAPTIVE ESTIMATION
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作者 Li Li Peng Yuhua +1 位作者 Yang Mingqiang Xue Peijun 《Journal of Electronics(China)》 2007年第3期358-362,共5页
Wavelet de-noising has been well known as an important method of signal de-noising. Recently,most of the research efforts about wavelet de-noising focus on how to select the threshold,where Donoho method is applied wi... Wavelet de-noising has been well known as an important method of signal de-noising. Recently,most of the research efforts about wavelet de-noising focus on how to select the threshold,where Donoho method is applied widely. Compared with traditional 2-band wavelet,3-band wavelet has advantages in many aspects. According to this theory,an adaptive signal de-noising method in 3-band wavelet domain based on nonparametric adaptive estimation is proposed. The experimental results show that in 3-band wavelet domain,the proposed method represents better characteristics than Donoho method in protecting detail and improving the signal-to-noise ratio of reconstruction signal. 展开更多
关键词 NONPARAMETRIC Adaptive estimation 3-band wavelet signal de-noising
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Coefficients de-noising with wavelet transform for magnetic flux leakage data obtained from oil pipeline
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作者 韩文花 Que Peiwen 《High Technology Letters》 EI CAS 2005年第4期406-409,共4页
This paper considers the problem of noise cancellation for the magnetic flux leakage (MFL) data obtained from the inspection of oil pipelines. MFL data is contaminated by various sources of noise, and the noise can co... This paper considers the problem of noise cancellation for the magnetic flux leakage (MFL) data obtained from the inspection of oil pipelines. MFL data is contaminated by various sources of noise, and the noise can considerably reduce the detectability of flaw signals in MFL data. This paper presents a new de-noising approach for removing the system noise contained in the MFL data by using the coefficients de-noising with wavelet transform. Experimental results are presented to demonstrate the advantages of this de-noising approach over the conventional wavelet de-noising method. 展开更多
关键词 magnetic flux leakage coefficients de-noising wavelet transform pipeline inspection system noise flaw signals
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手表情感化设计的滤波和特征提取技术研究
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作者 谢黎 史丰硕 +5 位作者 王雨晴 康晓管 罗光荣 尤思雨 于龙飞 郭建文 《包装工程》 北大核心 2025年第8期218-237,共20页
目的探讨特定人群手表产品的适宜滤波方法与生理特征指标。方法在梳理产品情感化设计流程中生理信号滤波和特征提取研究现状的基础上,搭建手表情感化意象实验平台,利用皮电信号、心电信号和脑电信号,基于Lasso回归探究人群特性下(大学... 目的探讨特定人群手表产品的适宜滤波方法与生理特征指标。方法在梳理产品情感化设计流程中生理信号滤波和特征提取研究现状的基础上,搭建手表情感化意象实验平台,利用皮电信号、心电信号和脑电信号,基于Lasso回归探究人群特性下(大学生、高校教师和职场白领)不同滤波和特征提取方法与产品情感意象的差异关联。结果皮电信号指标在各种滤波方法下呈现出较低的波动性,心电信号指标受“高通+低通”滤波方法的影响较大,脑电信号指标受“IMF+小波变换”滤波方法的影响较大;高校教师相较于大学生和职场白领在滤波方式上呈现出较高的稳定性;不同人群在效价、唤醒的Lasso回归图中保留的生理情感特征维度和数量不同。结论在产品情感化设计中应根据不同人群的生理特性,优选相应的滤波方法和特征提取指标,以准确建立“生理-产品情感意象”映射模型,实现产品形态与情感状态的有效融合。 展开更多
关键词 生理信号 信号处理技术 滤波 特征提取 产品情感化设计
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超声导波轨底裂纹检测的信号增强技术
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作者 何继平 周永久 +5 位作者 钦佩 张岩 周守镇 王平 周文涛 刘勇 《城市轨道交通研究》 北大核心 2025年第4期260-263,268,共5页
[目的]导波在钢轨中的传播过程中存在抗干扰能力差和信号衰减严重问题,不利于识别轨底裂纹。为提高信噪比,有必要提出一种信号增强技术用于增强导波信号。[方法]在传统超声导波检测基础上,利用Barker码作为伪随机序列码,采用BPSK(二进... [目的]导波在钢轨中的传播过程中存在抗干扰能力差和信号衰减严重问题,不利于识别轨底裂纹。为提高信噪比,有必要提出一种信号增强技术用于增强导波信号。[方法]在传统超声导波检测基础上,利用Barker码作为伪随机序列码,采用BPSK(二进制相位编码)技术将原始激励信号经过编码调制后得到新的激励信号,实现对激励信号的扩频处理,并对采集的接收信号进行解扩。搭建超声导波轨底裂纹检测试验平台,分别对不同尺寸的钢轨轨底人工裂纹进行对比试验,分别在激励信号扩频与非扩频情况下,计算所接收导波信号的衰减系数。[结果及结论]试验结果表明,导波信号使用信号增强技术之后,相较于未经处理的原始导波信号,在传播相同距离时,衰减系数得到了明显降低,超声导波信号将能传播更远距离;相同尺寸人工裂纹所产生的影响更加明显,超声导波对钢轨轨底裂纹的检测灵敏度得到了明显提升。 展开更多
关键词 轨道交通 钢轨裂纹检测 Barker码 超声导波 信号增强技术
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电子通信中多径信号强干扰滤波抑制仿真技术研究
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作者 赵培洪 何流 《移动信息》 2025年第1期26-28,共3页
随着通信技术的快速发展,传统的滤波方法已难以满足高效通信的需求。文中分析了多径信号与强干扰的交互特性,研究了多种现代滤波技术,并在仿真环境中进行了性能评估,旨在为通信系统的设计与优化提供理论支持和技术参考。
关键词 多径信号 强干扰 滤波抑制 仿真技术
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Integrated circuit for single channel neural signal regeneration 被引量:1
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作者 李文渊 王志功 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期155-158,共4页
Based on the 4-channel neural signal regeneration system which is realized by using discrete devices and successfully used for in-vivo experiments on rats and rabbits, a single channel neural signal regeneration integ... Based on the 4-channel neural signal regeneration system which is realized by using discrete devices and successfully used for in-vivo experiments on rats and rabbits, a single channel neural signal regeneration integrated circuit (IC)is designed and realized in CSMC ' s 0. 6 μm CMOS ( complementary metal-oxide-semiconductor transistor ) technology. The IC consists of a neural signal detection circuit with an adjustable gain, a buffer, and a function electrical stimulation (FES) circuit. The neural signal regenerating IC occupies a die area of 1.42 mm × 1.34 mm. Under a dual supply voltage of ±2. 5 V, the DC power consumption is less than 10 mW. The on-wafer measurement results are as follows: the output resistor is 118 ml), the 3 dB bandwidth is greater than 30 kHz, and the gain can be variable from 50 to 90 dB. The circuit is used for in-vivo experiments on the rat' s sciatic nerve as well as on the spinal cord with the cuff type electrode array and the twin-needle electrode. The neural signal is successfully regenerated both on a rat' s sciatic nerve bundle and on the spinal cord. 展开更多
关键词 neural signal regeneration function electrical stimulation integrated circuit ELECTRODE CMOS technology
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基于DT-CWT-LMS算法的煤矿井筒光纤监测数据自适应降噪研究
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作者 李子祥 蔡海兵 +1 位作者 程桦 侯公羽 《防灾减灾工程学报》 北大核心 2025年第1期158-168,共11页
为了解决在煤矿立井井筒监测现场应用中布里渊光时域反射仪(BOTDR)系统信噪比低的问题,提出了一种基于双树复小波变换(DT-CWT)和改进的LMS算法的组合降噪模型,用于对BOTDR分布式光纤监测信号进行降噪处理。首先,设计了基于双树复小波变... 为了解决在煤矿立井井筒监测现场应用中布里渊光时域反射仪(BOTDR)系统信噪比低的问题,提出了一种基于双树复小波变换(DT-CWT)和改进的LMS算法的组合降噪模型,用于对BOTDR分布式光纤监测信号进行降噪处理。首先,设计了基于双树复小波变换分解原始信号,并使用样本熵作为目标函数自动选择最优小波分解层数的模型,随后,使用LMS算法计算原始信号的自适应降噪阈值,并通过优化双曲余弦函数来改进LMS算法的收敛速度和收敛性。为了验证所提出算法的有效性,进行了BOTDR温度信号降噪实验,最后,依托山东省郭屯煤矿井筒监测项目,使用DT-CWT-LMS算法对光纤监测信号进行了降噪研究。实验结果表明,DT-CWT-LMS算法的降噪效果明显优于传统的小波阈值降噪方法,平均SNR指标提高了32.03%,平均RMSE降低了33.2%;现场研究结果表明,经过降噪后信号的样本熵平均降低幅度为64.75%,与光纤光栅传感器的数据对比相差在5%以内,说明信号中的背景噪声得到了有效的抑制。该研究为BOTDR技术在煤矿立井监测中应用提供了一种有效的信号降噪方法。 展开更多
关键词 井筒监测 信号降噪 分布式光纤技术 小波分析
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