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Group Hybrid Coordination Control of Multi-Agent Systems With Time-Delays and Additive Noises
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作者 Chuanjian Li Xiaofeng Zong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第3期737-748,共12页
A new kind of group coordination control problemgroup hybrid coordination control is investigated in this paper.The group hybrid coordination control means that in a whole multi-agent system(MAS)that consists of two s... A new kind of group coordination control problemgroup hybrid coordination control is investigated in this paper.The group hybrid coordination control means that in a whole multi-agent system(MAS)that consists of two subgroups with communications between them,agents in the two subgroups achieve consensus and containment,respectively.For MASs with both time-delays and additive noises,two group control protocols are proposed to solve this problem for the containment-oriented case and consensus-oriented case,respectively.By developing a new analysis idea,some sufficient conditions and necessary conditions related to the communication intensity betw een the two subgroups are obtained for the following two types of group hybrid coordination behavior:1)Agents in one subgroup and in another subgroup achieve weak consensus and containment,respectively;2)Agents in one subgroup and in another subgroup achieve strong consensus and containment,respectively.It is revealed that the decay of the communication impact betw een the two subgroups is necessary for the consensus-oriented case.Finally,the validity of the group control results is verified by several simulation examples. 展开更多
关键词 Additive noises consensus control containment control group hybrid coordination control multi-agent systems(MASs) TIME-DELAYS
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A Method for Reducing Ocean Wave-Induced Magnetic Noises in Shallow-Water MT Data Using a Complex Adaptive Filter
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作者 WU Yunju LUO Ming +2 位作者 LI Yuguo GE Jiaqi PAN Lindong 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第1期99-106,共8页
In shallow-water areas,the marine magnetotelluric(MT)method faces a challenge in the investigation of seabed conductivity structures due to electrical and magnetic noises induced by ocean waves,which seriously contami... In shallow-water areas,the marine magnetotelluric(MT)method faces a challenge in the investigation of seabed conductivity structures due to electrical and magnetic noises induced by ocean waves,which seriously contaminate MT data.Ocean waves can affect electric and magnetic fields to different extents.In general,their influence on magnetic fields is considerably greater than that on electric fields.In this paper,a complex adaptive filter is adopted to reduce wave-induced magnetic noises in the frequency domain.The processing results of synthetic and measured MT data indicate that the proposed method can effectively reduce wave-induced magnetic noises and provide reliable apparent resistivity and phase data. 展开更多
关键词 shallow-water areas wave-induced magnetic noises complex adaptive filter MT data processing
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Effective Denoising Architecture for Handling Multiple Noises
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作者 Na Hyoun Kim Namgyu Kim 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2667-2682,共16页
Object detection,one of the core research topics in computer vision,is extensively used in various industrial activities.Although there have been many studies of daytime images where objects can be easily detected,the... Object detection,one of the core research topics in computer vision,is extensively used in various industrial activities.Although there have been many studies of daytime images where objects can be easily detected,there is relatively little research on nighttime images.In the case of nighttime,various types of noises,such as darkness,haze,and light blur,deteriorate image quality.Thus,an appropriate process for removing noise must precede to improve object detection performance.Although there are many studies on removing individual noise,only a few studies handle multiple noises simultaneously.In this paper,we pro-pose a convolutional denoising autoencoder(CDAE)-based architecture trained on various types of noises.We also present various composing modules for each noise to improve object detection performance for night images.Using the exclusively dark(ExDark)Image dataset,experimental results show that the Sequentialfiltering architecture showed superior mean average precision(mAP)compared to other architectures. 展开更多
关键词 Object detection computer vision NIGHTTIME multiple noises convolutional denoising autoencoder
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Asymptotic Behavior of the Drift Coefficient Estimator of Stochastic Differential Equations Driven by Small Noises 被引量:3
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作者 沈亮 许青松 《Journal of Donghua University(English Edition)》 EI CAS 2015年第1期19-22,共4页
The parametric estimation problem for diffusion processes with small white noise based on continuous time observations is well developed. However,in parametric inference,it is more realistic and interesting to conside... The parametric estimation problem for diffusion processes with small white noise based on continuous time observations is well developed. However,in parametric inference,it is more realistic and interesting to consider asymptotic estimation for diffusion processes based on discrete observations. The least squares method is used to obtain the estimator of the drift parameter for stochastic differential equations( SDEs) driven by general Lévy noises when the process is observed discretely. Its strong consistency and the rate of convergence of the squares estimator are studied under some regularity conditions. 展开更多
关键词 stochastic differential equations(SDEs) consistency least squares estimator(LSE) discrete observations noises
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Stochastic resonance for a metapopulation system driven by multiplicative and additive colored noises 被引量:1
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作者 王康康 刘先斌 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期119-124,共6页
We investigate the stochastic resonance(SR) phenomenon induced by the periodic signal in a metapopulation system with colored noises. The analytical expression of signal-to-noise is derived in the adiabatic limit. By ... We investigate the stochastic resonance(SR) phenomenon induced by the periodic signal in a metapopulation system with colored noises. The analytical expression of signal-to-noise is derived in the adiabatic limit. By numerical calculation, the effects of the addictive noise intensity, the multiplicative noise intensity and two noise self-correlation times on SNR are respectively discussed. It shows that:(i) in the case that the addictive noise intensity M takes a small value, a SR phenomenon for the curve of SNR appears; however, when M takes a large value, SNR turns into a monotonic function on the multiplicative noise intensity Q.(ii) The resonance peaks in the plots of the multiplicative noise intensity Q versus its self-correlation time τ1 and the addictive noise intensity M versus its self-correlation time τ2 translate in parallel. Meanwhile, a parallel translation also appears in the plots of τ1 versus Q and τ2 versus M.(iii) The interactive effects between self-correlation times τ1 and τ2 are opposite. 展开更多
关键词 metapopulation Levins model COLORED noises SIGNAL-TO-NOISE ratio
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Escape of Brownian Particles in the System Driven by Correlated White Noises:Comparison of Three Models
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作者 YOU Jing-Yun CAO Li WU Da-Jin ZHANG Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第11期535-540,共6页
The relative escape rate (RER) in the bistable sawtooth system driven by correlated white noises was studied in the case of linear multiplicative noise coefficient.And we compare the RER of linear multiplicative noise... The relative escape rate (RER) in the bistable sawtooth system driven by correlated white noises was studied in the case of linear multiplicative noise coefficient.And we compare the RER of linear multiplicative noise coefficient with the RER of the piecewise constant multiplicative noise coefficient in the bistable sawtooth system,finally compare the RER of the bistable sawtooth potential with the RER of the quartic potential in the case of linear multiplicative noise coefficient.It can be seen that the form of the multiplicative noise coefficient and the nonlinearity of potential have an important influence on the resonant activation and the suppression of the RER.The resonant activation of the RER vanishes in the negative correlation when the multiplicative noise coefficient was shifted from piecewise constant to linear function in the bistable sawtooth potential.The suppression of the RER disappears in the negative correlation when thelinear potential is converted into nonlinear one. 展开更多
关键词 the CORRELATED noises escape rate resonant activation suppression
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Current transport and mass separation for an asymmetric fluctuation system with correlated noises
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作者 王杰 宁丽娟 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第1期289-293,共5页
We discuss the transport of an underdamped particle driven by an external fluctuation force in a spatially periodic asymmetric potential with correlated noises. The corresponding mathematical model is established. The... We discuss the transport of an underdamped particle driven by an external fluctuation force in a spatially periodic asymmetric potential with correlated noises. The corresponding mathematical model is established. The movement of the steady current of an underdamped particle is presented by the method of the numerical simulation. It is indicated that the value of the current may be negative, zero, or positive. The external fluctuation force and correlated noises can effect the current direction. Under the appropriate parameters, the correlated noises intensity may even raise a reversal of the current.Besides, we have noticed a phenomenon that particles with different weight have different directions during movement by the impact of the correlated noises and external fluctuation force. Therefore, the Brownian particles can be effectively separated according to their masses. 展开更多
关键词 current transport correlated noises fluctuation force Brownian motion
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Nearly nonstationary processes under infinite variance GARCH noises
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作者 ZHANG Rong-mao LIU Qi-meng SHI Jian-hua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第2期246-257,共12页
Let Y_(t) be an autoregressive process with order one,i.e.,Y_(t)=μ+ϕnY_(t-1)+εt,where fεtg is a heavy tailed general GARCH noise with tail indexα.Letϕn be the least squares estimator(LSE)ofϕn.Forμ=0 andα<2,it... Let Y_(t) be an autoregressive process with order one,i.e.,Y_(t)=μ+ϕnY_(t-1)+εt,where fεtg is a heavy tailed general GARCH noise with tail indexα.Letϕn be the least squares estimator(LSE)ofϕn.Forμ=0 andα<2,it is shown by Zhang and Ling(2015)thatϕn is inconsistent when Y_(t) is stationary(i.e.,ϕn.,ϕ<1),however,Chan and Zhang(2010)showed thatϕn is still consistent with convergence rate n when Y_(t) is a unit-root process(i.e.,ϕn=1)and fεtg is a GARCH(1,1)noise.There is a gap between the stationary and nonstationary cases.In this paper,two important issues will be considered:(1)what about the nearly unit root case?(2)When canϕbe estimated consistently by the LSE?We show that whenϕn=1-c/n,then bϕn converges to a functional of stable process with convergence rate n.Further,we show that if limn!1 kn(1-ϕn)=c for a positive constant c,then kn(ϕn-ϕ)converges to a functional of two stable variables with tail indexα/2,which means thatϕn can be estimated consistently only when kn!1. 展开更多
关键词 GARCH noises heavy-tailed stable processes and unit-root
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Global Dynamics of a Stochastic Two-Prey One-Predator Model with <i>S</i>-Type Distributed Delays and Lévy Noises
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作者 Taolin Zhang Yuanfu Shao Xiaowan She 《Journal of Applied Mathematics and Physics》 2020年第9期1959-1989,共31页
In this paper, a stochastic two-prey one-predator model with <em>S</em>-type distributed time delays and Lévy noises is considered. Using the comparison theorem and Ito’s formula, sufficient conditio... In this paper, a stochastic two-prey one-predator model with <em>S</em>-type distributed time delays and Lévy noises is considered. Using the comparison theorem and Ito’s formula, sufficient conditions of persistence in the mean and extinct for each population are established. Then, conditions of global attractivity and stability in distribution by Barbalat’s conclusion are also obtained. Furthermore, Euler numerical simulation method is given to demonstrate our conclusions. 展开更多
关键词 Distributed Delays Lévy noises Global Attractivity Stability in Distribution
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Nonstationary Filtering for Markov Jumping Systems with Fading Channel and Multiplicative Noises
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作者 Yang Zhan Daijun Wei 《Journal of Applied Mathematics and Physics》 2021年第4期529-544,共16页
This paper studies the nonstationary filtering problem of Markov jump system under <span style="white-space:nowrap;"><i>l</i><sub>2</sub> - <i>l</i><sub>... This paper studies the nonstationary filtering problem of Markov jump system under <span style="white-space:nowrap;"><i>l</i><sub>2</sub> - <i>l</i><sub>∞</sub> </span>performance. Due to the difference in propagation channels, signal strength and phase will inevitably change randomly and cause the waste of signals resources. In response to this problem, a channel fading model with multiplicative noise is introduced. And then a nonstationary filter, which receives signals more efficiently is designed. Meanwhile Lyapunov function is constructed for error analysis. Finally, the gain matrix for filtering is obtained by solving the matrix inequality, and the results showed that the nonstationary filter converges to the stable point more quickly than the traditional asynchronous filter, the stability of the designed filter is verified. 展开更多
关键词 Markov Jumping System l2 - l Performance Fading Channel Nonstationary Filtering Multiplicative noises
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Invariance and Noises of Shannon Entropy for Information on Oxidative Activity of DNA in All Living Cells for Medical Diagnostics
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作者 Nikolay E. Galich 《American Journal of Operations Research》 2014年第2期72-89,共18页
We analyze oxidative activity of DNA due to fluorescence of chromosomes inside cells, using flow cytometry method with nanometer spatial resolution. Statistics of fluorescence is presented in histogram as frequency di... We analyze oxidative activity of DNA due to fluorescence of chromosomes inside cells, using flow cytometry method with nanometer spatial resolution. Statistics of fluorescence is presented in histogram as frequency distributions of flashes in the dependence on their intensity and in distributions of Shannon entropy, which was defined on the base of normalized distribution of information in original histogram for frequency of flashes. We show that overall sum of entropy, i.e. total entropy E , for any histogram is invariant and has identical trends of changes all values of E(r) = lnr at reduction of histogram’ rank r. This invariance reflects informational homeostasis of chromosomes activity in multi-scale networks of entropy inside all cells in various samples of blood for DNA inside neutrophils, lymphocytes, inside all leukocytes of human and inside chicken erythrocytes for various dyes, colors and various excitations of fluorescence. Informational homeostasis of oxidative activity of 3D DNA in the full set of chromosomes inside living cells exists for any Shannon-Weaver index of biodiversity of cells, at any state of health different beings. Regulation perturbations in information activity DNA provides informational adaptability and vitality of cells at homeostasis support. Noises of entropy, during regulation of informational homeostasis, depend on the states of health in real time. The main structural reconstructions of chromosomal correlations, corresponding to self-regulation of homeostasis, occur in the most large-scale networks of entropy, for rank r<32. We show that stability of homeostasis is supported by activity of all 46 chromosomes inside cells. Patterns, hidden switching and branching in sequences of averages of H?lder and central moments for noises in regulation of homeostasis define new opportunities in diagnostics of health and immunity. All people and all aerobic beings have one overall homeostatic level for countdown of information activity of DNA inside cells. We noted very bad and dangerous properties of artificial cells with other levels of informational homeostasis for all aerobic beings in foods, medical treatment and in biotechnologies. 展开更多
关键词 Averages of Holder for noises of Shannon Entropy in Homeostasis Regulation of Total Shannon Entropy Entropy and Information of DNA Activity in Cells Information Entropy for Oxidizing Activity of DNA Informational Homeostasis and Self-Regulation of DNA Activity in Cells Noise of Information Entropy
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Statistical Properties of the Output Light Intensity in a Single-Mode Laser Driven by Correlated Noises 被引量:3
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作者 周小计 曹力 吴大进 《Chinese Physics Letters》 SCIE CAS CSCD 1998年第3期183-185,共3页
By using linear approximation we derive expressions for the correlation function,power spectrum and correlation time of the output light intensity in a single-mode laser driven by additive white noise and multiplicati... By using linear approximation we derive expressions for the correlation function,power spectrum and correlation time of the output light intensity in a single-mode laser driven by additive white noise and multiplicative colored noise with an exponential correlation form.The effects of correlation strength and correlation time of the noises on the above quantities are discussed and compared with the case of a delta function correlation form for the noises. 展开更多
关键词 noise FUNCTION INTENSITY
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Iterative Learning Disturbance Observer Based Attitude Stabilization of Flexible Spacecraft Subject to Complex Disturbances and Measurement Noises 被引量:3
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作者 Tongfu He Zhong Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第9期1576-1587,共12页
To realize high-precision attitude stabilization of a flexible spacecraft in the presence of complex disturbances and measurement noises,an iterative learning disturbance observer(ILDO)is presented in this paper.First... To realize high-precision attitude stabilization of a flexible spacecraft in the presence of complex disturbances and measurement noises,an iterative learning disturbance observer(ILDO)is presented in this paper.Firstly,a dynamic model of disturbance is built by augmenting the integral of the lumped disturbance as a state.Based on it,ILDO is designed by introducing iterative learning structures.Then,comparative analyses of ILDO and traditional disturbance observers are carried out in frequency domain.It demonstrates that ILDO combines the advantages of high accuracy in disturbance estimation and favorable robustness to measurement noise.After that,an ILDO based composite controller is designed to stabilize the spacecraft attitude.Finally,the effectiveness of the proposed control scheme is verified by simulations. 展开更多
关键词 Disturbance observer iterative learning measure-ment noise spacecraft attitude control
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Reentrant Transitions Induced by Correlation Between Colored Noises 被引量:2
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作者 周小计 曹力 吴大进 《Chinese Physics Letters》 SCIE CAS CSCD 1998年第4期243-245,共3页
In the study,a bistable system is driven by additive colored noise and multiplicative colored noise,whose correlation is of an exponential farm.When the noises are correlated,it is found that the system undergoes a re... In the study,a bistable system is driven by additive colored noise and multiplicative colored noise,whose correlation is of an exponential farm.When the noises are correlated,it is found that the system undergoes a reentrant transition as the correlation strength between noises or multiplicative noise intensity changes,while there is no such phenomenon as the additive noise intensity or the time of correlation changes.No reentrant transition exists when the noises are uncorrelated. 展开更多
关键词 ADDITIVE noise COLORED
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Escape Rate in the Bistable Sawtooth System Driven by Correlated Multiplicative and Additive White Noises 被引量:2
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作者 游敬云 曹力 +1 位作者 吴大进 梁贵云 《Chinese Physics Letters》 SCIE CAS CSCD 2001年第2期175-177,共3页
We study the escape problem of a bistable sawtooth system driven by correlated multiplicative and additive white noises.Exact analytic representation of the relative escape rate is obtained.Some novel phenomena are fo... We study the escape problem of a bistable sawtooth system driven by correlated multiplicative and additive white noises.Exact analytic representation of the relative escape rate is obtained.Some novel phenomena are found from the calculation result;“suppression platform”appears in the relative escape rate when the noise correlation coefficientλis positive.Moreover,for small positive values ofλ,the relative escape rate exhibits“suppression platform”and then“resonant activation”with the increasing noise strength ratio R. 展开更多
关键词 SAWTOOTH noise ACTIVATION
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Well-Posedness and Finite Element Approximations for Elliptic SPDEs with Gaussian Noises 被引量:2
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作者 Yanzhao Cao Jialin Hong Zhihui Liu 《Communications in Mathematical Research》 CSCD 2020年第2期113-127,共15页
The paper studies the well-posedness and optimal error estimates of spectral finite element approximations for the boundary value problems of semi-linear elliptic SPDEs driven by white or colored Gaussian noises.The n... The paper studies the well-posedness and optimal error estimates of spectral finite element approximations for the boundary value problems of semi-linear elliptic SPDEs driven by white or colored Gaussian noises.The noise term is approximated through the spectral projection of the covariance operator,which is not required to be commutative with the Laplacian operator.Through the convergence analysis of SPDEs with the noise terms replaced by the projected noises,the well-posedness of the SPDE is established under certain covariance operator-dependent conditions.These SPDEs with projected noises are then numerically approximated with the finite element method.A general error estimate framework is established for the finite element approximations.Based on this framework,optimal error estimates of finite element approximations for elliptic SPDEs driven by power-law noises are obtained.It is shown that with the proposed approach,convergence order of white noise driven SPDEs is improved by half for one-dimensional problems,and by an infinitesimal factor for higher-dimensional problems. 展开更多
关键词 Elliptic stochastic partial differential equation spectral approximations finite element approximations power-law noise
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Noises and Signal-to-Noise Ratio of Nanosize EIS and ISFET Biosensors 被引量:1
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作者 Lusine Gasparyan Ilya Mazo +1 位作者 Vahan Simonyan Ferdinand Gasparyan 《Open Journal of Biophysics》 2020年第1期1-12,共12页
The results of comparative theoretical analyzes of the behavior of internal low-frequency noises, signal-to-noise ratio and sensitivity to DNA molecules for EIS and ISFET based nanosize biosensors are presented. It is... The results of comparative theoretical analyzes of the behavior of internal low-frequency noises, signal-to-noise ratio and sensitivity to DNA molecules for EIS and ISFET based nanosize biosensors are presented. It is shown that EIS biosensor is more sensitive to the presence of DNA molecules in aqueous solution than ISFET sensor. Internal electrical noises level decreases with the increase of concentration of DNA molecules in aqueous solution. In the frequency range 10&minus;3 - 103 Hz noises level for EIS sensor about in three orders is higher than for ISFET sensor. In the other hand, signal-to-noise ratio for capacitive EIS biosensor is much higher than for ISFET sensor. 展开更多
关键词 BIOSENSOR Noise Sensitivity SIGNAL-TO-NOISE Ratio
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Internal Electrical Noises of BioFET Sensors Based on Various Architectures 被引量:1
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作者 Lusine Gasparyan Ferdinand Gasparyan Vahan Simonyan 《Open Journal of Biophysics》 2021年第2期177-204,共28页
The results of a comparative literature analysis of internal electrical noises and signal-to-noise ratio for nanoscale BioFET (biological field-effect transistor) and DNA (deoxyribonucleic acid) sensors based on diffe... The results of a comparative literature analysis of internal electrical noises and signal-to-noise ratio for nanoscale BioFET (biological field-effect transistor) and DNA (deoxyribonucleic acid) sensors based on different architectures MIS (metal-insulator-semiconductor), EIS (electrolyte-insulator-semi-conductor) and ISFET (ion-selective field-effect transistor) are presented. Main types, models and mechanisms of internal noises of bio- & chemical field-effect based sensors are analyzed, summarized and presented. For the first time, corresponding detail electrical equivalent circuits were built to calculate the spectral densities of noises generated in the active part of a solid (semiconductor, dielectric) and in an aqueous solution for MIS, EIS and ISFET structures based sensors. Complete expressions are obtained for the rms (root mean square) value of the noise current (or voltage), as well as the noise spectral densities for the architectures under study. The miniaturization of biosensors leads to a decrease in the level of the useful signal-current. For successful operation of the sensor, it is necessary to ensure a high value of the SNR (signal-to-noise ratio). In case of weak useful signals, it is necessary to reduce the level of internal electrical noise. This work is devoted to a detailed study of the types and mechanisms of internal electrical noises in specific biosensor architectures. 展开更多
关键词 Noise SENSOR BioFET Signal-to-Noise Ratio
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On-Line Suppression of Periodic Noises in Evoked Potentials
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作者 周卫 袁孝如 《The Journal of Biomedical Research》 CAS 1994年第1期1-4,共4页
On-LineSuppressionofPeriodicNoisesinEvokedPotentialsZhouWei(周卫)YuanXiaoru(袁孝如)(DepartmentofBiomathematics,Na... On-LineSuppressionofPeriodicNoisesinEvokedPotentialsZhouWei(周卫)YuanXiaoru(袁孝如)(DepartmentofBiomathematics,NanjingMedicalUnive... 展开更多
关键词 EVOKED POTENTIALS ON-LINE SUPPRESSION of PERIODIC noise
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ADAPTIVE ESTIMATION OF THE MEANS AND COVARIANCES OF SYSTEM NOISES
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作者 赵勇 《Journal of Southeast University(English Edition)》 EI CAS 1991年第1期91-98,共8页
This paper presents a simple and feasible method of estimating the means andcovariances of system noises.The information about the means and covariances is derivedfrom a suboptimal Kalman filter formed via the approxi... This paper presents a simple and feasible method of estimating the means andcovariances of system noises.The information about the means and covariances is derivedfrom a suboptimal Kalman filter formed via the approximate statistics.An efficientalgorithm is obtained through WLS(weighted-least-square)estimation by using themeasurement residuals of the suboptimal Kalman filter.Simulations are given to show theefficiency of the method. 展开更多
关键词 noise CHARACTERISTICS ESTIMATION KALMAN filtering/weighted-least-square ESTIMATION
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