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Time series analysis-based seasonal autoregressive fractionally integrated moving average to estimate hepatitis B and C epidemics in China
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作者 Yong-Bin Wang Si-Yu Qing +3 位作者 Zi-Yue Liang Chang Ma Yi-Chun Bai Chun-Jie Xu 《World Journal of Gastroenterology》 SCIE CAS 2023年第42期5716-5727,共12页
BACKGROUND Hepatitis B(HB)and hepatitis C(HC)place the largest burden in China,and a goal of eliminating them as a major public health threat by 2030 has been set.Making more informed and accurate forecasts of their s... BACKGROUND Hepatitis B(HB)and hepatitis C(HC)place the largest burden in China,and a goal of eliminating them as a major public health threat by 2030 has been set.Making more informed and accurate forecasts of their spread is essential for developing effective strategies,heightening the requirement for early warning to deal with such a major public health threat.AIM To monitor HB and HC epidemics by the design of a paradigmatic seasonal autoregressive fractionally integrated moving average(SARFIMA)for projections into 2030,and to compare the effectiveness with the seasonal autoregressive integrated moving average(SARIMA).METHODS Monthly HB and HC incidence cases in China were obtained from January 2004 to June 2023.Descriptive analysis and the Hodrick-Prescott method were employed to identify trends and seasonality.Two periods(from January 2004 to June 2022 and from January 2004 to December 2015,respectively)were used as the training sets to develop both models,while the remaining periods served as the test sets to evaluate the forecasting accuracy.RESULTS There were incidents of 23400874 HB cases and 3590867 HC cases from January 2004 to June 2023.Overall,HB remained steady[average annual percentage change(AAPC)=0.44,95%confidence interval(95%CI):-0.94-1.84]while HC was increasing(AAPC=8.91,95%CI:6.98-10.88),and both had a peak in March and a trough in February.In the 12-step-ahead HB forecast,the mean absolute deviation(15211.94),root mean square error(18762.94),mean absolute percentage error(0.17),mean error rate(0.15),and root mean square percentage error(0.25)under the best SARFIMA(3,0,0)(0,0.449,2)12 were smaller than those under the best SARIMA(3,0,0)(0,1,2)12(16867.71,20775.12,0.19,0.17,and 0.27,respectively).Similar results were also observed for the 90-step-ahead HB,12-step-ahead HC,and 90-step-ahead HC forecasts.The predicted HB incidents totaled 9865400(95%CI:7508093-12222709)cases and HC totaled 1659485(95%CI:856681-2462290)cases during 2023-2030.CONCLUSION Under current interventions,China faces enormous challenges to eliminate HB and HC epidemics by 2030,and effective strategies must be reinforced.The integration of SARFIMA into public health for the management of HB and HC epidemics can potentially result in more informed and efficient interventions,surpassing the capabilities of SARIMA. 展开更多
关键词 HEPATITIS Seasonal autoregressive fractionally integrated moving average Seasonal autoregressive integrated moving average Prediction EPIDEMIC Time series analysis
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PSO-DBNet for Peak-to-Average Power Ratio Reduction Using Deep Belief Network
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作者 A.Jameer Basha M.Ramya Devi +3 位作者 S.Lokesh P.Sivaranjani D.Mansoor Hussain Venkat Padhy 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1483-1493,共11页
Data transmission through a wireless network has faced various signal problems in the past decades.The orthogonal frequency division multiplexing(OFDM)technique is widely accepted in multiple data transfer patterns at... Data transmission through a wireless network has faced various signal problems in the past decades.The orthogonal frequency division multiplexing(OFDM)technique is widely accepted in multiple data transfer patterns at various frequency bands.A recent wireless communication network uses OFDM in longterm evolution(LTE)and 5G,among others.The main problem faced by 5G wireless OFDM is distortion of transmission signals in the network.This transmission loss is called peak-to-average power ratio(PAPR).This wireless signal distortion can be reduced using various techniques.This study uses machine learning-based algorithm to solve the problem of PAPR in 5G wireless communication.Partial transmit sequence(PTS)helps in the fast transfer of data in wireless LTE.PTS is merged with deep belief neural network(DBNet)for the efficient processing of signals in wireless 5G networks.Result indicates that the proposed system outperforms other existing techniques.Therefore,PAPR reduction in OFDM by DBNet is optimized with the help of an evolutionary algorithm called particle swarm optimization.Hence,the specified design supports in improving the proposed PAPR reduction architecture. 展开更多
关键词 5G wireless network orthogonal frequency division multiplexing signal distortion peak to average power ratio partial transmit sequence deep belief network
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Periodic signal extraction of GNSS height time series based on adaptive singular spectrum analysis
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作者 Chenfeng Li Peibing Yang +1 位作者 Tengxu Zhang Jiachun Guo 《Geodesy and Geodynamics》 EI CSCD 2024年第1期50-60,共11页
Singular spectrum analysis is widely used in geodetic time series analysis.However,when extracting time-varying periodic signals from a large number of Global Navigation Satellite System(GNSS)time series,the selection... Singular spectrum analysis is widely used in geodetic time series analysis.However,when extracting time-varying periodic signals from a large number of Global Navigation Satellite System(GNSS)time series,the selection of appropriate embedding window size and principal components makes this method cumbersome and inefficient.To improve the efficiency and accuracy of singular spectrum analysis,this paper proposes an adaptive singular spectrum analysis method by combining spectrum analysis with a new trace matrix.The running time and correlation analysis indicate that the proposed method can adaptively set the embedding window size to extract the time-varying periodic signals from GNSS time series,and the extraction efficiency of a single time series is six times that of singular spectrum analysis.The method is also accurate and more suitable for time-varying periodic signal analysis of global GNSS sites. 展开更多
关键词 GNSS Time series Singular spectrum analysis Trace matrix Periodic signal
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Subtraction of liposome signals in cryo-EM structural determination of protein-liposome complexes
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作者 李首卿 李明 +1 位作者 王玉梅 李雪明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期569-577,共9页
Reconstituting membrane proteins in liposomes and determining their structure is a common method for determining membrane protein structures using single-particle cryo-electron microscopy(cryo-EM).However,the strong s... Reconstituting membrane proteins in liposomes and determining their structure is a common method for determining membrane protein structures using single-particle cryo-electron microscopy(cryo-EM).However,the strong signal of liposomes under cryo-EM imaging conditions often interferes with the structural determination of the embedded membrane proteins.Here,we propose a liposome signal subtraction method based on single-particle two-dimensional(2D)classification average images,aimed at enhancing the reconstruction resolution of membrane proteins.We analyzed the signal distribution characteristics of liposomes and proteins within the 2D classification average images of protein–liposome complexes in the frequency domain.Based on this analysis,we designed a method to subtract the liposome signals from the original particle images.After the subtraction,the accuracy of single-particle three-dimensional(3D)alignment was improved,enhancing the resolution of the final 3D reconstruction.We demonstrated this method using a PIEZO1-proteoliposome dataset by improving the resolution of the PIEZO1 protein. 展开更多
关键词 CRYO-EM protein–liposome complexes liposome signal subtraction 2D classification averaging
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Automated Machine Learning Algorithm Using Recurrent Neural Network to Perform Long-Term Time Series Forecasting
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作者 Ying Su Morgan C.Wang Shuai Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期3529-3549,共21页
Long-term time series forecasting stands as a crucial research domain within the realm of automated machine learning(AutoML).At present,forecasting,whether rooted in machine learning or statistical learning,typically ... Long-term time series forecasting stands as a crucial research domain within the realm of automated machine learning(AutoML).At present,forecasting,whether rooted in machine learning or statistical learning,typically relies on expert input and necessitates substantial manual involvement.This manual effort spans model development,feature engineering,hyper-parameter tuning,and the intricate construction of time series models.The complexity of these tasks renders complete automation unfeasible,as they inherently demand human intervention at multiple junctures.To surmount these challenges,this article proposes leveraging Long Short-Term Memory,which is the variant of Recurrent Neural Networks,harnessing memory cells and gating mechanisms to facilitate long-term time series prediction.However,forecasting accuracy by particular neural network and traditional models can degrade significantly,when addressing long-term time-series tasks.Therefore,our research demonstrates that this innovative approach outperforms the traditional Autoregressive Integrated Moving Average(ARIMA)method in forecasting long-term univariate time series.ARIMA is a high-quality and competitive model in time series prediction,and yet it requires significant preprocessing efforts.Using multiple accuracy metrics,we have evaluated both ARIMA and proposed method on the simulated time-series data and real data in both short and long term.Furthermore,our findings indicate its superiority over alternative network architectures,including Fully Connected Neural Networks,Convolutional Neural Networks,and Nonpooling Convolutional Neural Networks.Our AutoML approach enables non-professional to attain highly accurate and effective time series forecasting,and can be widely applied to various domains,particularly in business and finance. 展开更多
关键词 Automated machine learning autoregressive integrated moving average neural networks time series analysis
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The IDD Transcription Factors:Their Functions in Plant Development and Environmental Response
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作者 Jing Liu Defeng Shu +5 位作者 Zilong Tan Mei Ma Huanhuan Yang Ning Guo Shipeng Li Dayong Cui 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第1期63-79,共17页
INDETERMINATE-DOMAIN proteins(IDDs)are a plant-specific transcription factor family characterized by a conserved ID domain with four zinc finger motifs.Previous studies have demonstrated that IDDs coordinate a diversi... INDETERMINATE-DOMAIN proteins(IDDs)are a plant-specific transcription factor family characterized by a conserved ID domain with four zinc finger motifs.Previous studies have demonstrated that IDDs coordinate a diversity of physiological processes and functions in plant growth and development,including floral transition,plant architecture,seed and root development,and hormone signaling.In this review,we especially summarized the latest knowledge on the functions and working models of IDD members in Arabidopsis,rice,and maize,particularly focusing on their role in the regulatory network of biotic and abiotic environmental responses,such as gravity,temperature,water,and pathogens.Understanding these mechanisms underlying the function of IDD proteins in these processes is important for improving crop yields by manipulating their activity.Overall,the review offers valuable insights into the functions and mechanisms of IDD proteins in plants,providing a foundation for further research and potential applications in agriculture. 展开更多
关键词 INDETERMINATE DOMAIN flowering time root development shoot gravitropism plant immunity hormonal signaling environmental responses
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Research on Instantaneous Angular Speed Signal Separation Method for Planetary Gear Fault Diagnosis
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作者 Xinkai Song Yibao Zhang Shuo Zhang 《Modern Mechanical Engineering》 2024年第2期39-50,共12页
Planetary gear train is a critical transmission component in large equipment such as helicopters and wind turbines. Conducting damage perception of planetary gear trains is of great significance for the safe operation... Planetary gear train is a critical transmission component in large equipment such as helicopters and wind turbines. Conducting damage perception of planetary gear trains is of great significance for the safe operation of equipment. Existing methods for damage perception of planetary gear trains mainly rely on linear vibration analysis. However, these methods based on linear vibration signal analysis face challenges such as rich vibration sources, complex signal coupling and modulation mechanisms, significant influence of transmission paths, and difficulties in separating damage information. This paper proposes a method for separating instantaneous angular speed (IAS) signals for planetary gear fault diagnosis. Firstly, this method obtains encoder pulse signals through a built-in encoder. Based on this, it calculates the IAS signals using the Hilbert transform, and obtains the time-domain synchronous average signal of the IAS of the planetary gear through time-domain synchronous averaging technology, thus realizing the fault diagnosis of the planetary gear train. Experimental results validate the effectiveness of the calculated IAS signals, demonstrating that the time-domain synchronous averaging technology can highlight impact characteristics, effectively separate and extract fault impacts, greatly reduce the testing cost of experiments, and provide an effective tool for the fault diagnosis of planetary gear trains. 展开更多
关键词 Planetary Gear Train Encoder signal Instantaneous Angular Speed signal Time-Domain Synchronous Averaging Fault Diagnosis
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An Improved Signal Segmentation Using Moving Average and Savitzky-Golay Filter 被引量:8
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作者 Hamed Azami Karim Mohammadi Behzad Bozorgtabar 《Journal of Signal and Information Processing》 2012年第1期39-44,共6页
Analysis of long-term EEG signals needs that it be segmented into pseudo stationary epochs. That work is done by regarding to statistical characteristics of a signal such as amplitude and frequency. Time series measur... Analysis of long-term EEG signals needs that it be segmented into pseudo stationary epochs. That work is done by regarding to statistical characteristics of a signal such as amplitude and frequency. Time series measured in real world is frequently non-stationary and to extract important information from the measured time series it is significant to utilize a filter or smoother as a pre-processing step. In the proposed approach, the signal is initially filtered by Moving Average (MA) or Savitzky-Golay filter to attenuate its short-term variations. Then, changes of the amplitude or frequency of the signal is calculated by Modified Varri method which is an acceptable algorithm for segmenting a signal. By using synthetic and real EEG data, the proposed methods are compared with original approach (simple Modified Varri). The simulation results indicate the absolute advantage of the proposed methods. 展开更多
关键词 NON-STATIONARY signal Adaptive Segmentation Modified Varri MOVING average (MA) FILTER Sa-vitzky-Golay FILTER
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Development of a wide-range and fast-response digitizing pulse signal acquisition and processing system for neutron flux monitoring on EAST 被引量:2
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作者 Li Yang Hong-Rui Cao +7 位作者 Jin-Long Zhao Zi-Han Zhang Qiang Li Guo-Bin Wu Yong-Qiang Zhang Guo-Qiang Zhong Li-Qun Hu Zi-Jun Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第3期126-136,共11页
The neutron count rate fluctuation reaches six orders of magnitude between the ohmic plasma scenario and high power of auxiliary heating on an experimental advanced superconducting tokamak(EAST).The measurement result... The neutron count rate fluctuation reaches six orders of magnitude between the ohmic plasma scenario and high power of auxiliary heating on an experimental advanced superconducting tokamak(EAST).The measurement result of neutron flux monitoring(NFM)is a significant feedback parameter related to the acquisition of radiation protection-related information and rapid fluctuations in neutron emission induced by plasma magnetohydrodynamic activity.Therefore,a wide range and high time resolution are required for the NFM system on EAST.To satisfy these requirements,a digital pulse signal acquisition and processing system with a wide dynamic range and fast response time was developed.The present study was conducted using a field-programmable gate array(FPGA)and peripheral component interconnect extension for instrument express(PXIe)platform.The digital dual measurement modes,which are composed of the pulse-counting mode and AC coupled square integral's Campbelling mode,were designed to expand the measurement range of the signal acquisition and processing system.The time resolution of the signal acquisition and processing system was improved from 10 to 1 ms owing to utilizing highspeed analog-to-digital converters(ADCs),a high-speed PXIe communication with a direct memory access(DMA)mode,and online data preprocessing technology of FPGA.The signal acquisition and processing system was tested experimentally in the EAST radiation field.The test results showed that the time resolution of NFM was improved to 1 ms,and the dynamic range of the neutron counts rate was expanded to more than 10^(6) counts per second.The Campbelling mode was calibrated using a multipoint average linear fitting method;subsequently,the fitting coefficient reached 0.9911.Therefore,the newly developed pulse signal acquisition and processing system ensures that the NFM system meets the requirements of high-parameter experiments conducted on EAST more effectively. 展开更多
关键词 EAST Neutron flux monitoring High time resolution Wide range Pulse signal acquisition and processing system
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Forecasting risk using auto regressive integrated moving average approach: an evidence from S&P BSE Sensex 被引量:2
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作者 Madhavi Latha Challa Venkataramanaiah Malepati Siva Nageswara Rao Kolusu 《Financial Innovation》 2018年第1期344-360,共17页
The primary objective of the paper is to forecast the beta values of companies listed on Sensex,Bombay Stock Exchange(BSE).The BSE Sensex constitutes 30 top most companies listed which are popularly known as blue-chip... The primary objective of the paper is to forecast the beta values of companies listed on Sensex,Bombay Stock Exchange(BSE).The BSE Sensex constitutes 30 top most companies listed which are popularly known as blue-chip companies.To reach out the predefined objectives of the research,Auto Regressive Integrated Moving Average method is used to forecast the future risk and returns for 10 years of historical data from April 2007 to March 2017.Validation accomplished by comparison of forecasted and actual beta values for the hold back period of 2 years.Root-Mean-Square-Error and Mean-Absolute-Error both are used for accuracy measurement.The results revealed that out of 30 listed companies in the BSE Sensex,10 companies’exhibits high beta values,12 companies are with moderate and 8 companies are with low beta values.Further,it is to note that Housing Development Finance Corporation(HDFC)exhibits more inconsistency in terms of beta values though the average beta value is lowest among the companies under the study.A mixed trend is found in forecasted beta values of the BSE Sensex.In this analysis,all the p-values are less than the F-stat values except the case of Tata Steel and Wipro.Therefore,the null hypotheses were rejected leaving Tata Steel and Wipro.The values of actual and forecasted values are showing the almost same results with low error percentage.Therefore,it is concluded from the study that the estimation ARIMA could be acceptable,and forecasted beta values are accurate.So far,there are many studies on ARIMA model to forecast the returns of the stocks based on their historical data.But,hardly there are very few studies which attempt to forecast the returns on the basis of their beta values.Certainly,the attempt so made is a novel approach which has linked risk directly with return.On the basis of the present study,authors try to through light on investment decisions by linking it with beta values of respective stocks.Further,the outcomes of the present study undoubtedly useful to academicians,researchers,and policy makers in their respective area of studies. 展开更多
关键词 Akaike Information Criteria(AIC) Bombay Stock Exchange(BSE) Auto Regressive Integrated Moving average(ARIMA) Beta Time series
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A QTC-based signal readout for position-sensitive multi-output detectors 被引量:2
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作者 Wei Zhou Zhi-Ming Zhang +14 位作者 Dao-Wu Li Pei-Lin Wang Bao-Tong Feng Xian-Chao Huang Ting-Ting Hu Xiao-Hui Li Yan Chen Ying-Jie Wang Yan-Tao Liu Yi-Wen Zhang Shi-Feng Sun Xiao-Yue Gu Ming-Jie Yang Xiong Xiao Long Wei 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第5期208-214,共7页
A new signal readout method for position-sensitive multi-output detectors,such as those in high-energy spectroscopy measurement and nuclear imaging,was developed by combining the charge division circuit,summing circui... A new signal readout method for position-sensitive multi-output detectors,such as those in high-energy spectroscopy measurement and nuclear imaging,was developed by combining the charge division circuit,summing circuit and charge-to-time conversion(QTC) circuit.The 64 outputs of a Hamamatsu H8500 position-sensitive photomultiplier tube were processed,and three digital pulses were generated.The widths of digital pulses were determined using the time-to-digital converter in an field programmable gate array.The energy and position information of incident y-rays is estimated based on the proportionality between the width of digital pulses and input charge created by y-photons.A prototype was built using discrete components and tested,and the energy and position resolutions were improved compared with that obtained with standard ADCs.This method greatly simplifies the front-end electronics and the digital interface.It enables a compact electronics system and an easy integration into an ASIC. 展开更多
关键词 输出信号 位置灵敏探测器 多输出 读出 位置灵敏光电倍增管 现场可编程门阵列 时间-数字转换器 位置敏感探测器
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The correlation between stochastic resonance and the average phase-synchronization time of a bistable system driven by colour-correlated noises
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作者 董小娟 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期136-142,共7页
This paper investigates the correlation between stochastic resonance (SR) and the average phase-synchronization time which is between the input signal and the output signal in a bistable system driven by colour-corr... This paper investigates the correlation between stochastic resonance (SR) and the average phase-synchronization time which is between the input signal and the output signal in a bistable system driven by colour-correlated noises. The results show that the output signal-to-noise ratio can reach a maximum with the increase of the average phase- synchronization time, which may be helpful for understanding the principle of SR from the point of synchronization; however, SR and the maximum of the average phase-synchronization time appear at different optimal noise level, moreover, the effects on them of additive and multiplicative noise are different. 展开更多
关键词 stochastic resonance phase-synchronization signal-to-noise ratio average phase- synchronization time
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Stochastic resonance in a time-delayed asymmetric bistable system with mixed periodic signal 被引量:1
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作者 郭永峰 徐伟 王亮 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期90-95,共6页
This paper studies the phenomenon of stochastic resonance in an asymmetric bistable system with time-delayed feedback and mixed periodic signal by using the theory of signal-to-noise ratio in the adiabatic limit. A ge... This paper studies the phenomenon of stochastic resonance in an asymmetric bistable system with time-delayed feedback and mixed periodic signal by using the theory of signal-to-noise ratio in the adiabatic limit. A general approximate Fokker-Planck equation and the expression of the signal-to-noise ratio are derived through the small time delay approximation at both fundamental harmonics and mixed harmonics. The effects of the additive noise intensity Q, multiplicative noise intensity D, static asymmetry r and delay time T on the signal-to-noise ratio are discussed. It is found that the higher mixed harmonics and the static asymmetry r can restrain stochastic resonance, and the delay time τ can enhance stochastic resonance. Moreover, the longer the delay time τ is, the larger the additive noise intensity Q and the multiplicative noise intensity D are, when the stochastic resonance appears. 展开更多
关键词 stochastic resonance time-delayed feedback mixed periodic signal signal-to-noise ratio
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Average Dwell-time Conditions for Consensus of Discrete-time Linear Multi-agent Systems with Switching Topologies and Time-varying Delays 被引量:4
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作者 GE Yan-Rong CHEN Yang-Zhou ZHANG Ya-Xiao 《自动化学报》 EI CSCD 北大核心 2014年第11期2609-2617,共9页
关键词 平均停留时间 拓扑结构 多AGENT系统 线性变换 时变延迟 离散时间 LYAPUNOV泛函 线性矩阵不等式
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X-ray pulsar signal detection using photon interarrival time
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作者 Qiang Xie Luping Xu Hua Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期899-905,共7页
The distribution probability of the photon interarrival time (PIT) without signal initial phases is derived based on the Poisson model of X-ray pulsar signals, and a pulsar signal detection algorithm employing the P... The distribution probability of the photon interarrival time (PIT) without signal initial phases is derived based on the Poisson model of X-ray pulsar signals, and a pulsar signal detection algorithm employing the PIT sequence is put forward. The joint probability of the PIT sequence is regarded as a function of the distribution probability and used to compare a constant radiation intensity model with the nonhomogeneous Poisson model for the signal detection. The relationship between the number of detected photons and the probabilities of false negative and positive is studied, and the success rate and mean detection time are estimated based on the number of the given photons. For the spacecraft velocity data detection, the changes of time of photon arrival (TOPA) and PIT caused by spacecraft motion are presented first, then the influences on detection are analyzed respectively. By using the analytical pulse profile of PSR B0531+21, the simulation of the Xray pulsar signal detection is implemented. The simulation results verify the effectiveness of the proposed method, and the contrast tests show that the proposed method is suitable for the spacecraft velocity data detection. 展开更多
关键词 pulsar signal detection photon interarrival time (PIT) Poisson model
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A Novel Peak-to-Average Power Ratio Reduction Scheme via Tone Reservation in OFDM Systems 被引量:1
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作者 Jurong Bai Yong Li +2 位作者 Wei Cheng Huimin Du Yanben Wang 《China Communications》 SCIE CSCD 2017年第11期279-290,共12页
In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme(SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multipl... In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme(SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multiplexing systems. During the SCR procedure, only the element with the maximal amplitude is picked for processing, which not only decreases the algorithm complexity, but also helps to overcome the BER deterioration. With the LSA method, the amplitude of the peak-cancelling signals can approximate to that of the original clipping noise as much as possible. Through the combination of the optimization factor in the LSA method, the classic SCR method can achieve better PAPR reduction with faster convergence. Simulation results show that the proposed SCR-LSA TR scheme has less in-band distortion and smaller out-of-band spectral radiation. The BER of the proposed scheme shows a better performance especially under the 16-QAM over the additive white Gaussian noise channel. 展开更多
关键词 orthogonal frequency division multiplexing peak-to-average power ratio tone reservation signal to clipping noise ratio
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Signal averaging for noise reduction in anesthesia monitoring and control with communication channels
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作者 Zhi-Bin Tan Le-Yi Wang Hong Wang 《Journal of Biomedical Science and Engineering》 2009年第7期564-573,共10页
This paper investigates impact of noise and signal averaging on patient control in anesthesia applications, especially in networked control system settings such as wireless connected systems, sensor networks, local ar... This paper investigates impact of noise and signal averaging on patient control in anesthesia applications, especially in networked control system settings such as wireless connected systems, sensor networks, local area networks, or tele-medicine over a wide area network. Such systems involve communication channels which introduce noises due to quantization, channel noises, and have limited communication bandwidth resources. Usually signal averaging can be used effectively in reducing noise effects when remote monitoring and diagnosis are involved. However, when feedback is intended, we show that signal averaging will lose its utility substantially. To explain this phenomenon, we analyze stability margins under signal averaging and derive some optimal strategies for selecting window sizes. A typical case of anesthe-sia depth control problems is used in this development. 展开更多
关键词 ANESTHESIA Depth ANESTHESIA Monitoring ANESTHESIA Control signal AVERAGING Noise Reduction Open and CLOSED LOOP SYSTEMS Communications NETWORKED SYSTEMS
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Parameter estimation of LFM signals based on time reversal 被引量:1
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作者 MA Xinjie QI Wei +1 位作者 CHE Kaijun WU Gang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期674-681,共8页
In this paper,parameter estimation of linear frequency modulation(LFM)signals containing additive white Gaussian noise is studied.Because the center frequency estimation of an LFM signal is affected by the error propa... In this paper,parameter estimation of linear frequency modulation(LFM)signals containing additive white Gaussian noise is studied.Because the center frequency estimation of an LFM signal is affected by the error propagation effect,resulting in a higher signal to noise ratio(SNR)threshold,a parameter estimation method for LFM signals based on time reversal is proposed.The proposed method avoids SNR loss in the process of estimating the frequency,thus reducing the SNR threshold.The simulation results show that the threshold is reduced by 5 dB compared with the discrete polynomial transform(DPT)method,and the root-mean-square error(RMSE)of the proposed estimator is close to the Cramer-Rao lower bound(CRLB). 展开更多
关键词 linear frequency modulation(LFM)signal time reversal Cramer-Rao lower bound(CRLB) parameter estimation
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Parameterized time-frequency analysis to separate multi-radar signals 被引量:1
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作者 Wenlong Lu Junwei Xie +1 位作者 Heming Wang Chuan Sheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期493-502,共10页
Multi-radar signal separation is a critical process in modern reconnaissance systems. However, the complicated battlefield is typically confronted with increasing electronic equipment and complex radar waveforms. The ... Multi-radar signal separation is a critical process in modern reconnaissance systems. However, the complicated battlefield is typically confronted with increasing electronic equipment and complex radar waveforms. The intercepted signal is difficult to separate with conventional parameters because of severe overlapping in both time and frequency domains. On the contrary, time-frequency analysis maps the 1D signal into a 2D time-frequency plane, which provides a better insight into the signal than traditional methods. Particularly, the parameterized time-frequency analysis (PTFA) shows great potential in processing such non stationary signals. Five procedures for the PTFA are proposed to separate the overlapped multi-radar signal, including initiation, instantaneous frequency estimation with PTFA, signal demodulation, signal separation with adaptive filter and signal recovery. The proposed method is verified with both simulated and real signals, which shows good performance in the application on multi-radar signal separation. 展开更多
关键词 intercepted multi-radar signal parameterized time-frequency analysis DEMODULATION adaptive filtering
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Kravchenko atomic transforms in digital signal processing 被引量:2
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作者 V.F.Kravchenko D.V.Churikov 《Journal of Measurement Science and Instrumentation》 CAS 2012年第3期228-234,共7页
The modified atomic transformations are constructed and proved. On their basis the new complex analytic wavelets are obtained. The proof of the Fourier transforms existence in L~ and L2 on the basis of the theory of a... The modified atomic transformations are constructed and proved. On their basis the new complex analytic wavelets are obtained. The proof of the Fourier transforms existence in L~ and L2 on the basis of the theory of atomic functions (AF) are presented. The numerical experiments of digital time series processing and physical analysis of the results confirm the efficiency of the proposed transforms. 展开更多
关键词 atomic functions(AF) Fourier series space-time transforms digital signal processing(DSP)
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