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The application of Gaussian distribution deconvolution method to separate the overlapping signals in the 2D NMR map
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作者 Kou-Qi Liu Zheng-Chen Zhang Mehdi Ostadhassan 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1513-1520,共8页
The 2D NMR(T_(1)-T_(2))mapping technique,which can be used to separate different proton populations from various sources(hydroxyls,solid organic matter,free water,and free HC)has gained attention in petroleum industry... The 2D NMR(T_(1)-T_(2))mapping technique,which can be used to separate different proton populations from various sources(hydroxyls,solid organic matter,free water,and free HC)has gained attention in petroleum industry.To separate proton contributions,a fixed straight line is commonly employed to separate different regions representing proton sources on the map.However,some of these regions(Region 1 and 2)might overlap which makes extracting the NMR signal amplitude from these regions inaccurate.In order to solve this issue,in this study,we applied the Gaussian distribution deconvolution method to separate the T_(1)and T_(2)relaxation distributions and then derived the signal amplitude of each region instead of following the common fixed line approach.Next,we employed this method to analyze several shale samples from the literature and compared the results following both methods to verify our methodology.Finally,samples from the Bakken Shale were studied to separate signals from Region 1 and Region 2 and corelated the results with geochemical properties that were obtained from programmed(Rock Eval)pyrolysis.Results demonstrated an improvement in their relation when our approach is employed compared to the fixed line technique to differentiate signal from overlapping regions.This means the Gaussian distribution deconvolution method can be used with confidence to provide us with more accurate petrophysical and geochemical understanding of complex formations. 展开更多
关键词 2D NMR Signal amplitude gaussian distribution Shale formations
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Particle size spatial distribution in landslide dams
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作者 ZHANG Jingyi ZHANG Jianmin 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1886-1903,共18页
The particle composition and spatial distribution of landslide-induced dam bodies are critical geotechnical parameters for studying the hazards of dam-break floods.However,current research often neglects the influence... The particle composition and spatial distribution of landslide-induced dam bodies are critical geotechnical parameters for studying the hazards of dam-break floods.However,current research often neglects the influence of the initial particle composition and spatial distribution of the landslide on the particle composition and spatial distribution of the landslide dam.This study investigated the impact of initial particle size distribution,volume,and sliding length on the energy and velocity changes of characteristic particles during the sliding process and the spatial distribution of particle sizes in the landslide dam body.Numerical simulations and physical models were employed to examine the effects of sequential gradient arrangements(where particle sizes decrease from top to bottom)and four other different initial particle arrangements on the energy and velocity changes of particles and the spatial distribution of particle sizes in the dam body.The study reveals the characteristics of translational and rotational energy of different particles and the laws of mechanical energy conversion,obtaining the spatial distribution patterns of particle sizes in landslide-induced dams.The results show that under the sequential gradient arrangement,the energy dissipation of the landslide movement is lower,with larger particles mainly distributed at the distal end and smaller particles at the proximal end of the landslide dam.In contrast,under the reverse gradient arrangement,the energy dissipation of the landslide movement is higher,and the distribution pattern of the dam particles is opposite to that of the sequential gradient arrangement.For the other arrangement modes,the spatial distribution of dam particles falls between the aforementioned two.There is a positive correlation between particle size and translational kinetic energy within the particle flow during the landslide process,and rotational motion increases energy dissipation.Under constant slope conditions,sliding length does not affect the movement pattern of the particle flow or the spatial distribution of particles in the dam body.The findings of this study provide a scientific basis for the accurate simulation and prediction of dam-break flood processes. 展开更多
关键词 Particle size distribution LANDSLIDE Numerical simulation discrete element method
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A Gaussian Noise-Based Algorithm for Enhancing Backdoor Attacks
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作者 Hong Huang Yunfei Wang +1 位作者 Guotao Yuan Xin Li 《Computers, Materials & Continua》 SCIE EI 2024年第7期361-387,共27页
Deep Neural Networks(DNNs)are integral to various aspects of modern life,enhancing work efficiency.Nonethe-less,their susceptibility to diverse attack methods,including backdoor attacks,raises security concerns.We aim... Deep Neural Networks(DNNs)are integral to various aspects of modern life,enhancing work efficiency.Nonethe-less,their susceptibility to diverse attack methods,including backdoor attacks,raises security concerns.We aim to investigate backdoor attack methods for image categorization tasks,to promote the development of DNN towards higher security.Research on backdoor attacks currently faces significant challenges due to the distinct and abnormal data patterns of malicious samples,and the meticulous data screening by developers,hindering practical attack implementation.To overcome these challenges,this study proposes a Gaussian Noise-Targeted Universal Adversarial Perturbation(GN-TUAP)algorithm.This approach restricts the direction of perturbations and normalizes abnormal pixel values,ensuring that perturbations progress as much as possible in a direction perpendicular to the decision hyperplane in linear problems.This limits anomalies within the perturbations improves their visual stealthiness,and makes them more challenging for defense methods to detect.To verify the effectiveness,stealthiness,and robustness of GN-TUAP,we proposed a comprehensive threat model.Based on this model,extensive experiments were conducted using the CIFAR-10,CIFAR-100,GTSRB,and MNIST datasets,comparing our method with existing state-of-the-art attack methods.We also tested our perturbation triggers using various defense methods and further experimented on the robustness of the triggers against noise filtering techniques.The experimental outcomes demonstrate that backdoor attacks leveraging perturbations generated via our algorithm exhibit cross-model attack effectiveness and superior stealthiness.Furthermore,they possess robust anti-detection capabilities and maintain commendable performance when subjected to noise-filtering methods. 展开更多
关键词 Image classification model backdoor attack gaussian distribution Artificial Intelligence(AI)security
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Estimation of Hourly and Daily Global Solar Radiation at Clear Days Using an Approach Based on Modified Version of Gaussian Distribution 被引量:4
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作者 S.M EI shazly 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1996年第3期349-358,共10页
The performance of two models,Jam and Baig,based on the modified version of Gaussian distribution function in estimating the daily total of global solar radiation and its distribution through the hours of the day from... The performance of two models,Jam and Baig,based on the modified version of Gaussian distribution function in estimating the daily total of global solar radiation and its distribution through the hours of the day from sunrise to sunset al any clear day is evaluated with our own measured data in the period from June 1992 to May 1993 in Qena Egypt The results show a high relative deviation of calculated values from measured ones,especially for Jain model,in the most hours of the day,except for those near to local noon.This misfit behavior is quite obvious in the early morning and late afternoon A new approach has been proposed in this paper to estimate the daily and hourly global solar radiation This model performs with very high accuracy on the recorded data in our region.The validity of this approach was verified with new measurements in some clear days in June and August 1994.The resultant very low relative deviation of the calculated values of global solar radiation from the measured ones confirms the high performance of the approach proposed in this work 展开更多
关键词 Glohal solar radiation . Measurements Models gaussian distribution function Statistical treatment
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LEAST SQUARES TYPE ESTIMATION FOR DISCRETELY OBSERVED NON-ERGODIC GAUSSIAN ORNSTEIN-UHLENBECK PROCESSES 被引量:1
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作者 Khalifa ES-SEBAIY Fares ALAZEMI Mishari AL-FORAIH 《Acta Mathematica Scientia》 SCIE CSCD 2019年第4期989-1002,共14页
In this article, we consider the drift parameter estimation problem for the nonergodic Ornstein-Uhlenbeck process defined as dXt = OXtdt + dGt, i > 0 with an unknown parameter θ> 0, where G is a Gaussian proces... In this article, we consider the drift parameter estimation problem for the nonergodic Ornstein-Uhlenbeck process defined as dXt = OXtdt + dGt, i > 0 with an unknown parameter θ> 0, where G is a Gaussian process. We assume that the process {xt,t≥ 0} is observed at discrete time instants t1=△n,…, tn = n△n, and we construct two least squares type estimators θn and θn for θ on the basis of the discrete observations ,{xti,i= 1,…, n} as →∞. Then, we provide sufficient conditions, based on properties of G, which ensure that θn and θn are strongly consistent and the sequences √n△n(θn-θ) and √n△n(θn-θ) are tight. Our approach offers an elementary proof of [11], which studied the case when G is a fractional Brownian motion with Hurst parameter H∈(1/2, 1). As such, our results extend the recent findings by [11] to the case of general Hurst parameter H∈(0,1). We also apply our approach to study subfractional Ornstein-Uhlenbeck and bifractional Ornstein-Uhlenbeck processes. 展开更多
关键词 Drift parameter ESTIMATION non-ergodic gaussian ORNSTEIN-UHLENBECK process discrete observations
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Deterministic quantum key distribution based on Gaussian-modulated EPR correlations 被引量:1
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作者 何广强 曾贵华 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第6期1284-1289,共6页
This paper proposes a deterministic quantum key distribution scheme based on Gaussian-modulated continuous variable EPR correlations. This scheme can implement fast and efficient key distribution. The security is guar... This paper proposes a deterministic quantum key distribution scheme based on Gaussian-modulated continuous variable EPR correlations. This scheme can implement fast and efficient key distribution. The security is guaranteed by continuous variable EPR entanglement correlations produced by nondegenerate optical parametric amplifier. For general beam splitter eavesdropping strategy, the secret information rate ΔI = I(α, β)-I(α, ε) is calculated in view of Shannon information theory. Finally the security analysis is presented. 展开更多
关键词 quantum key distribution continuous variable EPR correlation gaussian modulation
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Derivation of Gaussian Probability Distribution: A New Approach 被引量:2
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作者 A. T. Adeniran O. Faweya +1 位作者 T. O. Ogunlade K. O. Balogun 《Applied Mathematics》 2020年第6期436-446,共11页
The famous de Moivre’s Laplace limit theorem proved the probability density function of Gaussian distribution from binomial probability mass function under specified conditions. De Moivre’s Laplace approach is cumbe... The famous de Moivre’s Laplace limit theorem proved the probability density function of Gaussian distribution from binomial probability mass function under specified conditions. De Moivre’s Laplace approach is cumbersome as it relies heavily on many lemmas and theorems. This paper invented an alternative and less rigorous method of deriving Gaussian distribution from basic random experiment conditional on some assumptions. 展开更多
关键词 De Moivres Laplace Limit Theorem Binomial Probability Mass Function gaussian distribution Random Experiment
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Mechanical properties of double-stranded DNA biofilm with Gaussian distribution 被引量:1
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作者 Heng-Song Tang Wei-Lie Meng Neng-Hui Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第1期15-19,共5页
In microcantilever-based label-free biodetection technologies, deflection changes induced by adsorptions of double-stranded DNA (dsDNA) molecules on Au-layer surface are greatly affected by the mechanical, thermal a... In microcantilever-based label-free biodetection technologies, deflection changes induced by adsorptions of double-stranded DNA (dsDNA) molecules on Au-layer surface are greatly affected by the mechanical, thermal and electrical properties of DNA biofilm. In this paper, the elastic properties of dsDNA biofilm are studied. First, the Parsegian's empirical potential based on a mesoscopic liq- uid crystal theory is employed to describe the interaction energy among coarse-grained DNA cylinders. Then, con- sidering a Gaussian distribution of DNA interaxial distance, the thought experiment method is used to derive an analyti- cal expression for Young's modulus of DNA biofilm with a stochastic packing pattern for the first time. Results show that Young's modulus of DNA biofilm is on the order of 10 MPa. These findings could provide a simple and effective method to evaluate the mechanical properties of soft biofilm on snbstrate. 展开更多
关键词 Double-stranded DNA. BiofilmElastic modu-lus - Cylinder model gaussian distribution
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Moved Score Confidence Intervals for Means of Discrete Distributions 被引量:1
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作者 Yu Guan 《Open Journal of Statistics》 2011年第2期81-86,共6页
Let X denote a discrete distribution as Poisson, binomial or negative binomial variable. The score confidence interval for the mean of X is obtained based on inverting the hypothesis test and the central limit theorem... Let X denote a discrete distribution as Poisson, binomial or negative binomial variable. The score confidence interval for the mean of X is obtained based on inverting the hypothesis test and the central limit theorem is discussed and recommended widely. But it has sharp downward spikes for small means. This paper proposes to move the score interval left a little (about 0.04 unit), called by moved score confidence interval. Numerical computation and Edgeworth expansion show that the moved score interval is analogous to the score interval completely and behaves better for moderate means;for small means the moved interval raises the infimum of the coverage probability and improves the sharp spikes significantly. Especially, it has unified explicit formulations to compute easily. 展开更多
关键词 CONFIDENCE INTERVAL CONFIDENCE Level COVERAGE PROBABILITY discrete distribution Moved SCORE CONFIDENCE INTERVAL
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Gaussian process assisted coevolutionary estimation of distribution algorithm for computationally expensive problems 被引量:1
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作者 罗娜 钱锋 +1 位作者 赵亮 钟伟民 《Journal of Central South University》 SCIE EI CAS 2012年第2期443-452,共10页
In order to reduce the computation of complex problems, a new surrogate-assisted estimation of distribution algorithm with Gaussian process was proposed. Coevolution was used in dual populations which evolved in paral... In order to reduce the computation of complex problems, a new surrogate-assisted estimation of distribution algorithm with Gaussian process was proposed. Coevolution was used in dual populations which evolved in parallel. The search space was projected into multiple subspaces and searched by sub-populations. Also, the whole space was exploited by the other population which exchanges information with the sub-populations. In order to make the evolutionary course efficient, multivariate Gaussian model and Gaussian mixture model were used in both populations separately to estimate the distribution of individuals and reproduce new generations. For the surrogate model, Gaussian process was combined with the algorithm which predicted variance of the predictions. The results on six benchmark functions show that the new algorithm performs better than other surrogate-model based algorithms and the computation complexity is only 10% of the original estimation of distribution algorithm. 展开更多
关键词 estimation of distribution algorithm fitness function modeling gaussian process surrogate approach
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Investigation of the inhomogeneous barrier height of an Au/Bi_4Ti_3O_(12)/n-Si structure through Gaussian distribution of barrier height
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作者 M.Gken M.Yildirim 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期538-543,共6页
A Au/Bi4Ti3O12/n-Si structure is fabricated in order to investigate its current voltage (IV) characteristics in a temperature range of 300 K-400 K. Obtained I-V data are evaluated by the thermionic emission (TE) t... A Au/Bi4Ti3O12/n-Si structure is fabricated in order to investigate its current voltage (IV) characteristics in a temperature range of 300 K-400 K. Obtained I-V data are evaluated by the thermionic emission (TE) theory. Zero-bias barrier height (Ф0) and ideality factor (n) calculated from I-V characteristics, are found to be temperature-dependent such that ФB0 increases with temperature increasing, whereas n decreases. The obtained temperature dependence of ФB0 and linearity in ФB0 versus the n plot, together with a lower barrier height and Richardson constant values obtained from the Richardson plot, indicate that the barrier height of the structure is inhomogeneous in nature. Therefore, I-V characteristics are explained on the basis of Caussian distribution of barrier height. 展开更多
关键词 BI4TI3O12 I-V characterization temperature dependence gaussian distribution
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What Is the Difference between Gamma and Gaussian Distributions?
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作者 Xiao-Li Hu 《Applied Mathematics》 2013年第2期285-289,共5页
An inequality describing the difference between Gamma and Gaussian distributions is derived. The asymptotic bound is much better than by existing uniform bound from Berry-Esseen inequality.
关键词 GAMMA distribution gaussian distribution Berry-Esseen INEQUALITY CHARACTERISTIC Function
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Heavy-Tailed Distributions Generated by Randomly Sampled Gaussian, Exponential and Power-Law Functions
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作者 Frederic von Wegner 《Applied Mathematics》 2014年第13期2050-2056,共7页
A simple stochastic mechanism that produces exact and approximate power-law distributions is presented. The model considers radially symmetric Gaussian, exponential and power-law functions inn= 1, 2, 3 dimensions. Ran... A simple stochastic mechanism that produces exact and approximate power-law distributions is presented. The model considers radially symmetric Gaussian, exponential and power-law functions inn= 1, 2, 3 dimensions. Randomly sampling these functions with a radially uniform sampling scheme produces heavy-tailed distributions. For two-dimensional Gaussians and one-dimensional exponential functions, exact power-laws with exponent –1 are obtained. In other cases, densities with an approximate power-law behaviour close to the origin arise. These densities are analyzed using Padé approximants in order to show the approximate power-law behaviour. If the sampled function itself follows a power-law with exponent –α, random sampling leads to densities that also follow an exact power-law, with exponent -n/a – 1. The presented mechanism shows that power-laws can arise in generic situations different from previously considered specialized systems such as multi-particle systems close to phase transitions, dynamical systems at bifurcation points or systems displaying self-organized criticality. Thus, the presented mechanism may serve as an alternative hypothesis in system identification problems. 展开更多
关键词 Heavy-Tailed distributionS Random Sampling gaussian EXPONENTIAL POWER-LAW
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Mathematical simulation of burden distribution in COREX 3000 shaft by discrete element method
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作者 LI Qiang~(1)),ZHANG Lijuan~(2)) and ZOU Zongshu~(1)) 1) Northeastern University,Shenyang 110004,Liaoning,China 2) Baoshan Iron & Steel Co.,Ltd.,Shanghai 200941,China 《Baosteel Technical Research》 CAS 2010年第S1期7-,共1页
The distribution of reducing gas in a shaft furnace dominates the temperature profile,gas utilization ratio,metallization degree and is the overwhelming factor for stable,high productivities and low-energy-consumption... The distribution of reducing gas in a shaft furnace dominates the temperature profile,gas utilization ratio,metallization degree and is the overwhelming factor for stable,high productivities and low-energy-consumption operation.At the same time,the distribution of gas flow is mainly determined by the position of gas inlet,the packed bed porosity distribution as well as its change due to the difference on the mode of top charge and bottom discharge.When injecting position of the process is fixed,the charge mode is the only means for regulating the gas flow distribution.In this paper,a numerical simulation model of burden distribution in the shaft furnace of COREX 3000 has been developed to analyze the porosity distribution under the different charge modes by means of Discrete Element Method(DEM).The effects of the particle size and its distribution under conditions of different charge batches,chute angle,stoke line on the burden surface shape and burden bed particle size distribution and segregation were investigated,and then the porosity distribution in the shaft of corresponding charging pattern was quantitatively accessed.Therefore,the results can be used to optimize the charge patterns base on required gas distribution. 展开更多
关键词 COREX shaft furnace burden distribution reduce gas flow discrete Element Method
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Oversampling Method Based on Gaussian Distribution and K-Means Clustering
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作者 Masoud Muhammed Hassan Adel Sabry Eesa +1 位作者 Ahmed Jameel Mohammed Wahab Kh.Arabo 《Computers, Materials & Continua》 SCIE EI 2021年第10期451-469,共19页
Learning from imbalanced data is one of the greatest challenging problems in binary classification,and this problem has gained more importance in recent years.When the class distribution is imbalanced,classical machin... Learning from imbalanced data is one of the greatest challenging problems in binary classification,and this problem has gained more importance in recent years.When the class distribution is imbalanced,classical machine learning algorithms tend to move strongly towards the majority class and disregard the minority.Therefore,the accuracy may be high,but the model cannot recognize data instances in the minority class to classify them,leading to many misclassifications.Different methods have been proposed in the literature to handle the imbalance problem,but most are complicated and tend to simulate unnecessary noise.In this paper,we propose a simple oversampling method based on Multivariate Gaussian distribution and K-means clustering,called GK-Means.The new method aims to avoid generating noise and control imbalances between and within classes.Various experiments have been carried out with six classifiers and four oversampling methods.Experimental results on different imbalanced datasets show that the proposed GK-Means outperforms other oversampling methods and improves classification performance as measured by F1-score and Accuracy. 展开更多
关键词 Class imbalance OVERSAMPLING gaussian multivariate distribution k-means clustering
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A Normal Weighted Inverse Gaussian Distribution for Skewed and Heavy-Tailed Data
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作者 Calvin B. Maina Patrick G. O. Weke +1 位作者 Carolyne A. Ogutu Joseph A. M. Ottieno 《Applied Mathematics》 2022年第2期163-177,共15页
High frequency financial data is characterized by non-normality: asymmetric, leptokurtic and fat-tailed behaviour. The normal distribution is therefore inadequate in capturing these characteristics. To this end, vario... High frequency financial data is characterized by non-normality: asymmetric, leptokurtic and fat-tailed behaviour. The normal distribution is therefore inadequate in capturing these characteristics. To this end, various flexible distributions have been proposed. It is well known that mixture distributions produce flexible models with good statistical and probabilistic properties. In this work, a finite mixture of two special cases of Generalized Inverse Gaussian distribution has been constructed. Using this finite mixture as a mixing distribution to the Normal Variance Mean Mixture we get a Normal Weighted Inverse Gaussian (NWIG) distribution. The second objective, therefore, is to construct and obtain properties of the NWIG distribution. The maximum likelihood parameter estimates of the proposed model are estimated via EM algorithm and three data sets are used for application. The result shows that the proposed model is flexible and fits the data well. 展开更多
关键词 Inverse gaussian Finite Mixture Weighted distribution Mixed Model EM-ALGORITHM
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Research on Gaussian distribution preprocess method of infrared multispectral image background clutter
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作者 张伟 武春风 +1 位作者 邓盼 范宁 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第5期513-515,共3页
This paper introduces a sliding-window mean removal high pass filter by which background clutter of infrared multispectral image is obtained. The method of selecting the optimum size of the sliding-window is based on ... This paper introduces a sliding-window mean removal high pass filter by which background clutter of infrared multispectral image is obtained. The method of selecting the optimum size of the sliding-window is based on the skewness-kurtosis test. In the end, a multivariate Gaussian distribution mathematical expression of background clutter image is given. 展开更多
关键词 infrared multispectral imagery background clutter Sliding-window mean removal Skewness-kurtosis test multivariate gaussian distribution
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Space Charge Effect of Bunched Beam With Gaussian Distribution
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作者 Chen, Yinbao Fu, Shinian +1 位作者 Huang, Zhibin Zhang, Zhenhai 《Chinese journal of nuclear physics》 EI 1995年第2期174-178,共5页
The nonlinear space charge effect of a bunched beam with Gaussian distribu-tion in the longitudinal direction is discussed.Some useful formulae are derived for cal-culating the potential induced by a cylinder model of... The nonlinear space charge effect of a bunched beam with Gaussian distribu-tion in the longitudinal direction is discussed.Some useful formulae are derived for cal-culating the potential induced by a cylinder model of space charge in the waveguide of alinac with different combinations of density distribution:Gaussian distribution in thelongitudinal direction versus Kapchinskij Vladimirskij,waterbag,parabolic andGaussian distribution in the transverse direction,rcspectively. 展开更多
关键词 gaussian distribution in the longitudinal direction SPACE CHARGE EFFECT Bunched BEAM
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Analytical Evaluation of Non-Elementary Integrals Involving Some Exponential, Hyperbolic and Trigonometric Elementary Functions and Derivation of New Probability Measures Generalizing the Gamma-Type and Gaussian-Type Distributions 被引量:1
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作者 Victor Nijimbere 《Advances in Pure Mathematics》 2020年第7期371-392,共22页
The non-elementary integrals involving elementary exponential, hyperbolic and trigonometric functions, <img src="Edit_699140d3-f569-463e-b835-7ccdab822717.png" width="290" height="22" ... The non-elementary integrals involving elementary exponential, hyperbolic and trigonometric functions, <img src="Edit_699140d3-f569-463e-b835-7ccdab822717.png" width="290" height="22" alt="" /><img src="Edit_bdd10470-9b63-4b2d-9cec-636969547ca5.png" width="90" height="22" alt="" /><span style="white-space:normal;">and <img src="Edit_e9cd6876-e2b8-45cf-ba17-391f054679b4.png" width="90" height="21" alt="" /></span>where <span style="white-space:nowrap;"><em>&#945;</em>,<span style="white-space:nowrap;"><em>&#951;</em></span><em></em></span> and <span style="white-space:nowrap;"><em>&#946;</em></span> are real or complex constants are evaluated in terms of the confluent hypergeometric function <sub>1</sub><em>F</em><sub>1</sub> and the hypergeometric function <sub>1</sub><em>F</em><sub>2</sub>. The hyperbolic and Euler identities are used to derive some identities involving exponential, hyperbolic, trigonometric functions and the hypergeometric functions <sub style="white-space:normal;">1</sub><em style="white-space:normal;">F</em><sub style="white-space:normal;">1</sub> and <sub style="white-space:normal;">1</sub><em style="white-space:normal;">F</em><sub style="white-space:normal;">2</sub>. Having evaluated, these non-elementary integrals, some new probability measures generalizing the gamma-type and Gaussian distributions are also obtained. The obtained generalized probability distributions may, for example, allow to perform better statistical tests than those already known (e.g. chi-square (<span style="white-space:nowrap;"><em>&#120;</em><sup>2</sup></span>) statistical tests and other statistical tests constructed based on the central limit theorem (CLT)), while avoiding the use of computational approximations (or methods) which are in general expensive and associated with numerical errors. 展开更多
关键词 Non-Elementary Integrals Hypergeometric Function Confluent Hypergeometric Function Probability Measure Generalized Gamma-Type distributions Generalized gaussian-Type distributions
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Free Energy and Emittance Growth Caused by Bunched Beam With Gaussian Distribution in Longitudinal Direction in Linac
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作者 Huang Zhibin Chen Yinbao Fu Shinian China Institule of Atomic Energy,P.O.Box 275(17),Beijing 102413 《Chinese journal of nuclear physics》 1996年第4期236-243,共8页
The nonlinear space charge effect of bunched beam in linac is one of the important factors thatinduces the emittance growth due to the conversion of the field energy to kinetic energy.In this paper,us-ing a cylinder m... The nonlinear space charge effect of bunched beam in linac is one of the important factors thatinduces the emittance growth due to the conversion of the field energy to kinetic energy.In this paper,us-ing a cylinder model of space charge in linac,we derived the internal energy for a bunched beam withsome nonuniform space charge distributions,such as longitudinal Gaussian distribution combined withKapchinskij-Vladimirski1,waterbag,parabolic or Gaussian transverse distribution.And the emittancegrowth caused by the above distributions is worked out. 展开更多
关键词 —Emittance growth Longitudinal gaussian distribution TRANSVERSE NONUNIFORM distribution
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