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Reliability Function of Non-independent Random Variables Subject to Two-Dimensional Standard Normal Distribution
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作者 Yangjing Chong Xinhui Zhou +2 位作者 Yutong Zhu Hailing Lan Yunfei Guo 《信息工程期刊(中英文版)》 2016年第4期93-98,共6页
关键词 可靠性 分发 标准 二维 非独立 随机 案例分析
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Neural network study of the nuclear ground-state spin distribution within a random interaction ensemble
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作者 Deng Liu Alam Noor A +1 位作者 Zhen-Zhen Qin Yang Lei 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期216-227,共12页
The distribution of the nuclear ground-state spin in a two-body random ensemble(TBRE)was studied using a general classification neural network(NN)model with two-body interaction matrix elements as input features and t... The distribution of the nuclear ground-state spin in a two-body random ensemble(TBRE)was studied using a general classification neural network(NN)model with two-body interaction matrix elements as input features and the corresponding ground-state spins as labels or output predictions.The quantum many-body system problem exceeds the capability of our optimized NNs in terms of accurately predicting the ground-state spin of each sample within the TBRE.However,our NN model effectively captured the statistical properties of the ground-state spin because it learned the empirical regularity of the ground-state spin distribution in TBRE,as discovered by physicists. 展开更多
关键词 Neural network Two-body random ensemble Spin distribution of nuclear ground state
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Three dimensional distribution of surfactant in microspheres revealed by synchrotron radiation X-ray microcomputed tomography 被引量:2
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作者 Li Wu Manli Wang +7 位作者 Vikramjeet Singh Haiyan Li Zhen Guo Shuangying Gui Peter York Tiqiao Xiao Xianzhen Yin Jiwen Zhang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2017年第4期326-334,共9页
This study investigated the formulation mechanism of microspheres via internal surfactant distribution. Eudragit L100 based microspheres loaded with bovine serum albumin were prepared by solid in oil in oil emulsion s... This study investigated the formulation mechanism of microspheres via internal surfactant distribution. Eudragit L100 based microspheres loaded with bovine serum albumin were prepared by solid in oil in oil emulsion solvent evaporation method using acetone and liquid paraffin system containing sucrose stearate as a surfactant. The fabricated microspheres were evaluated for encapsulation efficiency, particle size, production yield, and in vitro release characteristics. The internal structures of microspheres were characterized using synchrotron radiation X-ray microcomputed tomography(SR-μCT). The enhanced contrast made the sucrose stearate distinguished from Eudragit to have its three dimensional(3D) distribution. Results indicated that the content and concentration determined the state of sucrose stearate and had significant influences on the release kinetics of protein. The dispersity of sucrose stearate was the primary factor that controlled the structure of the microspheres and further affected the encapsulation efficiency, effective drug loading, as well as in vitro release behavior. In conclusion, the 3D internal distribution of surfactant in microspheres and its effects on protein release behaviors have been revealed for the first time. The highly resolved 3D architecture provides new evidence for the deep understanding of the microsphere formation mechanism. 展开更多
关键词 Three dimensional SYNCHROTRON radiation X-RAY microcomputed tomography distribution MICROSPHERE SUCROSE STEARATE
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Three-dimensional analysis of elastic stress distribution of indented ceramic surface by finite element method 被引量:1
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作者 Tatsuyuki NEZU 《中国有色金属学会会刊:英文版》 CSCD 2006年第B02期551-557,共7页
The three-dimensional stress distributions in the area surrounding indentation pattern for three different materials, Al2O3, Si3N4 and SiC were analyzed by finite element method(FEM). Those theoretical results were al... The three-dimensional stress distributions in the area surrounding indentation pattern for three different materials, Al2O3, Si3N4 and SiC were analyzed by finite element method(FEM). Those theoretical results were also compared with the experimental ones by Rockwell hardness test. The effect of loading stress on the plastic deformation in specimens, surface was investigated on the assumption of shear strain energy theory by Huber-Mises when the materials were indented. The distributions of nomal stress, shear stress, and Mises stress were analysed with variations of loading conditions. It is clear that the analytical results for the stress distributions, the crack length and its density of probability are in good agreement with the experimental results. 展开更多
关键词 锯齿状陶瓷表面 弹性应力分布 有限元法 三维分析
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Spatial Density Distributions and Correlations in a Quasi-one-Dimensional Polydisperse Granular Gas
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作者 CHEN Zhi-Yuan ZHANG Duan-Ming 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期259-264,共6页
By Monte Carlo simulations, the effect of the dispersion of particle size distribution on the spatial density distributions and correlations of a quasi one-dimensional polydisperse granular gas with fractal size distr... By Monte Carlo simulations, the effect of the dispersion of particle size distribution on the spatial density distributions and correlations of a quasi one-dimensional polydisperse granular gas with fractal size distribution is investigated in the same inelasticity. The dispersive degree of the particle size distribution can be measured by a fractal dimension dr, and the smooth particles are constrained to move along a circle of length L, colliding inelastically with each other and thermalized by a viscosity heat bath. When the typical relaxation time τ of the driving Brownian process is longer than the mean collision time To, the system can reach a nonequilibrium steady state. The average energy of the system decays exponentially with time towards a stable asymptotic value, and the energy relaxation time τB to the steady state becomes shorter with increasing values of df. In the steady state, the spatial density distribution becomes more clusterized as df increases, which can be quantitatively characterized by statistical entropy of the system. Furthermore, the spatial correlation functions of density and velocities are found to be a power-law form for small separation distance of particles, and both of the correlations become stronger with the increase of df. Also, tile density clusterization is explained from the correlations. 展开更多
关键词 granular gas INELASTICITY fractal dimension df spatial density distributions spatial correlationsof density and velocities
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Simulation study on reconstruction model of three-dimensional temperature distribution within visible range in furnace 被引量:1
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作者 刘冬 王飞 +3 位作者 黄群星 严建华 池涌 岑可法 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第4期1312-1317,共6页
This paper presents a reconstruction model of three-dimensional temperature distribution in furnace based on radiative energy images captured by charge-coupled device (CCD) cameras within the visible wavelength rang... This paper presents a reconstruction model of three-dimensional temperature distribution in furnace based on radiative energy images captured by charge-coupled device (CCD) cameras within the visible wavelength range. Numerical simulation case was used in this study and a zigzag eccentric temperature distribution was assumed to verify the model. Least square QR-factorization (LSQR) method was introduced to deal with reconstruction equation. It is found that the reconstructed temperature distributions in low-temperature areas had some fluctuations and high-temperature areas were reconstructed well. The whole reconstruction relative error was mainly due to errors in low-temperature areas and the relative error for highest-temperature reconstruction was quite small. 展开更多
关键词 three-dimensional temperature distribution radiative energy images visible range charge-coupled device
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Attacking a high-dimensional quantum key distribution system with wavelength-dependent beam splitter
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作者 Ge-Hai Du Hong-Wei Li +1 位作者 Yang Wang Wan-Su Bao 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第9期87-92,共6页
The unconditional security of quantum key distribution(QKD) can be guaranteed by the nature of quantum physics.Compared with the traditional two-dimensional BB84 QKD protocol, high-dimensional quantum key distribution... The unconditional security of quantum key distribution(QKD) can be guaranteed by the nature of quantum physics.Compared with the traditional two-dimensional BB84 QKD protocol, high-dimensional quantum key distribution(HDQKD) can be applied to generate much more secret key.Nonetheless, practical imperfections in realistic systems can be exploited by the third party to eavesdrop the secret key.The practical beam splitter has a correlation with wavelength,where different wavelengths have different coupling ratios.Using this property, we propose a wavelength-dependent attack towards time-bin high-dimensional QKD system.What is more, we demonstrate that this attacking protocol can be applied to arbitrary d-dimensional QKD system, and higher-dimensional QKD system is more vulnerable to this attacking strategy. 展开更多
关键词 HIGH-dimensional quantum key distribution beam SPLITTER wavelength ATTACK
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Observation of the Two-Dimensional Distribution of Impurity Line Emissions Using a Space-Resolved EUV Spectrometer in LHD
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作者 王二辉 S.MORITA +1 位作者 M.GOTO 董春凤 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第2期106-109,共4页
A space-resolved EUV spectrometer for measuring the one-dimensional distribution of impurity line emissions in Large Helical Device (LHD) has been upgraded to measure two- dimensional distributions of impurity line ... A space-resolved EUV spectrometer for measuring the one-dimensional distribution of impurity line emissions in Large Helical Device (LHD) has been upgraded to measure two- dimensional distributions of impurity line emissions with an extension of working wavelength range to 30-650% The two-dimensional measurement is performed by scanning the observation chord horizontally. A rectangular plasma region of 520 × 700 mm2 in vertical and horizontal sizes can be observed during a single horizontal scan. The horizontal scan requires a time duration of 5 s at least. The spatial resolution is 10 mm in the vertical direction when a spatial-resolution slit of 0.2 mm in width is adopted. Although a spatial resolution in the toroidal direction is 75 mm, it is a function of CCD exposure time and horizontal scanning speed. Two-dimensional distribution of EUV line emissions from several impurities has been successfully observed for the first time from steady discharges in LHD. In this paper two-dimensional distributions of He II (303.78A), C V (40.27A), C VI (33.73A) and Fe XX (132.85A) located at different radial positions are presented with simple analysis on the magnetic field structure of LHD. 展开更多
关键词 EUV spectrometer impurity line emission two-dimensional distribution
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A new finite-dimensional thermal coherent state and its Wigner distribution function
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作者 孟祥国 王继锁 梁宝龙 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期371-376,共6页
This paper constructs a new type of finite-dimensional thermal coherent states (FDTCS), which differs from the proceeding thermal coherent state in construction, as realisations of SU(2) Lie algebra. Using the tec... This paper constructs a new type of finite-dimensional thermal coherent states (FDTCS), which differs from the proceeding thermal coherent state in construction, as realisations of SU(2) Lie algebra. Using the technique of integration within an ordered product of operator, it investigates the orthonormality and completeness relation of the FDTCS. Based on the thermal Wigner operator in the thermal entangled state representation, the Wigner function of the FDTCS is obtained. The nonclassical properties of the FDTCS are discussed in terms of the negativity of its Wigner function. 展开更多
关键词 new finite-dimensional thermal coherent state thermal entangled state representation Wigner distribution function
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Gravity effect calculation of threedimensional linear density distribution andits application
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作者 楼海 王椿镛 《Acta Seismologica Sinica(English Edition)》 EI CSCD 1999年第3期327-334,共8页
An algorithm for calculating gravity effect of three-dimensional (3D) linear density distribution is presented in this paper. The linear continuous density distribution is represented with 3D grid model, which has a ... An algorithm for calculating gravity effect of three-dimensional (3D) linear density distribution is presented in this paper. The linear continuous density distribution is represented with 3D grid model, which has a resemblance to the velocity model used in some seismic tomography codes. The consensus in representation method of density model and velocity model facilitates the seismic-gravity-integrated interpretation or simultaneous inversion. The numerical test of synthetic data shows that although the analytical gravity formula for linear density distribution is more complex than that for piecewise constant density distribution, it takes less time to calculate the gravity effect with linear density model than that with piecewise constant density model. In addition, this method is used in the integrated interpretation of 3D seismological tomography and gravity data in Dabie Mountain area. 展开更多
关键词 three-dimensional linear density distribution analytical gravity formula seismic-gravityintegrated interpretation
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Stability Analysis of Multi-Dimensional Linear Discrete System and Root Distribution Using Sign Criterion with Real Coefficients
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作者 Periyasamy Ramesh 《Circuits and Systems》 2016年第3期100-109,共10页
A new idea was proposed to find out the stability and root location of multi-dimensional linear time invariant discrete system (LTIDS) for real coefficient polynomials. For determining stability the sign criterion is ... A new idea was proposed to find out the stability and root location of multi-dimensional linear time invariant discrete system (LTIDS) for real coefficient polynomials. For determining stability the sign criterion is synthesized from the Jury’s method for stability which is derived from the characteristic polynomial coefficients of the discrete system. The number of roots lying inside or outside the unit circle and hence on the unit circle is directly determined from the proposed single modified Jury tabulation and the sign criterion. The proposed scheme is simple and the examples are given to bring out the merits of the proposed scheme which is also applicable for the singular and non-singular cases. 展开更多
关键词 Root distribution Inside the Unit Circle Outside the Unit Circle Characteristics Polynomial MULTI-dimensional
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CONSISTENCY OF MLE OF THE PARAMETER OF EXPONENTIAL LIFETIME DISTRIBUTION FOR RANDOM CENSORING MODEL WITH INCOMPLETE INFORMATION 被引量:18
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作者 YE ERHUA 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1995年第4期379-386,共8页
In this paper, we have discussed a random censoring test with incomplete information, and proved that the maximum likelihood estimator(MLE) of the parameter based on the randomly censored data with incomplete informat... In this paper, we have discussed a random censoring test with incomplete information, and proved that the maximum likelihood estimator(MLE) of the parameter based on the randomly censored data with incomplete information in the case of the exponential distribution has the strong consistency. 展开更多
关键词 random censoring test with incomplete information exponential distribution maximum likelihood estimator consistency.
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Optimization by Estimation of Distribution with DEUM Framework Based on Markov Random Fields 被引量:5
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作者 Siddhartha Shakya John McCall 《International Journal of Automation and computing》 EI 2007年第3期262-272,共11页
This paper presents a Markov random field (MRP) approach to estimating and sampling the probability distribution in populations of solutions. The approach is used to define a class of algorithms under the general he... This paper presents a Markov random field (MRP) approach to estimating and sampling the probability distribution in populations of solutions. The approach is used to define a class of algorithms under the general heading distribution estimation using Markov random fields (DEUM). DEUM is a subclass of estimation of distribution algorithms (EDAs) where interaction between solution variables is represented as an undirected graph and the joint probability of a solution is factorized as a Gibbs distribution derived from the structure of the graph. The focus of this paper will be on describing the three main characteristics of DEUM framework, which distinguishes it from the traditional EDA. They are: 1) use of MRF models, 2) fitness modeling approach to estimating the parameter of the model and 3) Monte Carlo approach to sampling from the model. 展开更多
关键词 Estimation of distribution algorithms evolutionary algorithms fitness modeling Markov random fields Gibbs distri-bution.
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Random Attractors for Stochastic Reaction-Diffusion Equations with Distribution Derivatives on Unbounded Domains 被引量:3
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作者 Eshag Mohamed Ahmed Ali Dafallah Abdelmajid +1 位作者 Ling Xu Qiaozhen Ma 《Applied Mathematics》 2015年第10期1790-1807,共18页
In this paper, we prove the existence of random attractors for a stochastic reaction-diffusion equation with distribution derivatives on unbounded domains. The nonlinearity is dissipative for large values of the state... In this paper, we prove the existence of random attractors for a stochastic reaction-diffusion equation with distribution derivatives on unbounded domains. The nonlinearity is dissipative for large values of the state and the stochastic nature of the equation appears spatially distributed temporal white noise. The stochastic reaction-diffusion equation is recast as a continuous random dynamical system and asymptotic compactness for this demonstrated by using uniform estimates far-field values of solutions. The results are new and appear to be optimal. 展开更多
关键词 STOCHASTIC REACTION-DIFFUSION Equation random ATTRACTORS distribution DERIVATIVES Asymptotic Compactness Unbounded Domain
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THE VALUE DISTRIBUTION OF RANDOM ANALYTIC DIRICHLET SERIES OF NEUTRAL GROWTH(I) 被引量:1
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作者 丁晓庆 《Acta Mathematica Scientia》 SCIE CSCD 1999年第2期234-240,共7页
This paper deals with the value distribution of random Dirichlet series whose coefficients are a martingale difference sequence, and which is of neutral growth.
关键词 Value distribution random DIRICHLET series MARTINGALE DIFFERENCE sequence.
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THE VALUE DISTRIBUTION OF RANDOM ANALYTIC DIRICHLET SERIES OF NEUTRAL GROWTH (Ⅱ) 被引量:1
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作者 丁晓庆 《Acta Mathematica Scientia》 SCIE CSCD 2000年第4期504-510,共7页
This paper studies the value distribution of random analytic Dirichlet series f(s) = Zn()e-sn, where {Zn} is a sequence of independent random variables, n = 1 with moments zero, such that infE{Zn}/E1/2{Zn2≥ α > ... This paper studies the value distribution of random analytic Dirichlet series f(s) = Zn()e-sn, where {Zn} is a sequence of independent random variables, n = 1 with moments zero, such that infE{Zn}/E1/2{Zn2≥ α > 0. Suppose [h*(σ)]2 = n converges for any α > 0, and diverges for = 0. It is shown that if = ρ E (0, ), then with probability one, where β is a constant depending only upon the constant α. 展开更多
关键词 Value distribution exceptional value random Dirichlet series independent random variab
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Efficient slope reliability analysis under soil spatial variability using maximum entropy distribution with fractional moments
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作者 Chengxin Feng Marcos A.Valdebenito +3 位作者 Marcin Chwała Kang Liao Matteo Broggi Michael Beer 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1140-1152,共13页
Spatial variability of soil properties imposes a challenge for practical analysis and design in geotechnical engineering.The latter is particularly true for slope stability assessment,where the effects of uncertainty ... Spatial variability of soil properties imposes a challenge for practical analysis and design in geotechnical engineering.The latter is particularly true for slope stability assessment,where the effects of uncertainty are synthesized in the so-called probability of failure.This probability quantifies the reliability of a slope and its numerical calculation is usually quite involved from a numerical viewpoint.In view of this issue,this paper proposes an approach for failure probability assessment based on Latinized partially stratified sampling and maximum entropy distribution with fractional moments.The spatial variability of geotechnical properties is represented by means of random fields and the Karhunen-Loève expansion.Then,failure probabilities are estimated employing maximum entropy distribution with fractional moments.The application of the proposed approach is examined with two examples:a case study of an undrained slope and a case study of a slope with cross-correlated random fields of strength parameters under a drained slope.The results show that the proposed approach has excellent accuracy and high efficiency,and it can be applied straightforwardly to similar geotechnical engineering problems. 展开更多
关键词 SLOPE random field Reliability analysis Maximum entropy distribution Latinized partial stratified sampling
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THE STATIONARY DISTRIBUTION OF A CONTINUOUS-TIME RANDOM GRAPH PROCESS WITH INTERACTING EDGES 被引量:1
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作者 韩东 《Acta Mathematica Scientia》 SCIE CSCD 1994年第S1期98-102,共5页
In previous papers, the stationary distributions of a class of discrete and continuoustime random graph processes with state space consisting of the simple and directed graphs on Nvenices were studied. In this paper, ... In previous papers, the stationary distributions of a class of discrete and continuoustime random graph processes with state space consisting of the simple and directed graphs on Nvenices were studied. In this paper, the random graph graph process is extended one impotent stepfurther by allowing interaction of edges. Similarly, We obtha the expressions of the stationarydistributions and prove that the process is ergodic under different editions. 展开更多
关键词 random graph prooes Minimum Q-process Stationary distribution Ergodicity.
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Degree distribution of random birth-and-death network with network size decline 被引量:1
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作者 张晓军 杨会兰 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期71-77,共7页
In this paper,we provide a general method to obtain the exact solutions of the degree distributions for random birthand-death network(RBDN) with network size decline.First,by stochastic process rules,the steady stat... In this paper,we provide a general method to obtain the exact solutions of the degree distributions for random birthand-death network(RBDN) with network size decline.First,by stochastic process rules,the steady state transformation equations and steady state degree distribution equations are given in the case of m ≥ 3 and 0 〈 p 〈 1/2,then the average degree of network with n nodes is introduced to calculate the degree distributions.Specifically,taking m = 3 for example,we explain the detailed solving process,in which computer simulation is used to verify our degree distribution solutions.In addition,the tail characteristics of the degree distribution are discussed.Our findings suggest that the degree distributions will exhibit Poisson tail property for the declining RBDN. 展开更多
关键词 random birth-and-death network(RBDN) Markov chain generating function degree distribution
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Modeling random telegraph signal noise in CMOS image sensor under low light based on binomial distribution 被引量:2
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作者 张钰 逯鑫淼 +2 位作者 王光义 胡永才 徐江涛 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期164-170,共7页
The random telegraph signal noise in the pixel source follower MOSFET is the principle component of the noise in the CMOS image sensor under low light. In this paper, the physical and statistical model of the random t... The random telegraph signal noise in the pixel source follower MOSFET is the principle component of the noise in the CMOS image sensor under low light. In this paper, the physical and statistical model of the random telegraph signal noise in the pixel source follower based on the binomial distribution is set up. The number of electrons captured or released by the oxide traps in the unit time is described as the random variables which obey the binomial distribution. As a result,the output states and the corresponding probabilities of the first and the second samples of the correlated double sampling circuit are acquired. The standard deviation of the output states after the correlated double sampling circuit can be obtained accordingly. In the simulation section, one hundred thousand samples of the source follower MOSFET have been simulated,and the simulation results show that the proposed model has the similar statistical characteristics with the existing models under the effect of the channel length and the density of the oxide trap. Moreover, the noise histogram of the proposed model has been evaluated at different environmental temperatures. 展开更多
关键词 random telegraph signal noise physical and statistical model binomial distribution CMOS image sensor
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