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Chinese Physics B 2012年第12期21卷 538-543页

作者： M.Gken M.Yildirim Department of Physics Faculty of Arts and SciencesDuzce University

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.

关键词： Bi4Ti3O12 I-V characterization temperature dependence gaussian distribution

The application of gaussian distribution deconvolution method to separate the overlapping signals in the 2D NMR map

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Petroleum Science 2023年第3期20卷 1513-1520页

作者： Kou-Qi Liu Zheng-Chen Zhang Mehdi Ostadhassan Institute of Energy Peking UniversityBejing100871China Instituteof Gscienes Marineand Land Gmechanics and GeoeconicsChiian Abrech-Universitat KielGmay Department of Geology Ferdowsi University of MashhadMashadIran

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 *** separate proton contributions,a fixed straight line is commonly employed to separate different regions representing proton sources on the ***,some of these regions(Region 1 and 2)might overlap which makes extracting the NMR signal amplitude from these regions *** 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 ***,we employed this method to analyze several shale samples from the literature and compared the results following both methods to verify our ***,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)*** demonstrated an improvement in their relation when our approach is employed compared to the fixed line technique to differentiate signal from overlapping *** means the gaussian distribution deconvolution method can be used with confidence to provide us with more accurate petrophysical and geochemical understanding of complex formations.

关键词： 2D NMR Signal amplitude gaussian distribution Shale formations

Mechanical properties of double-stranded DNA biofilm with gaussian distribution

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Acta Mechanica Sinica 2014年第1期30卷 15-19页

作者： Heng-Song Tang Wei-Lie Meng Neng-Hui Zhang Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsShanghai University Department of Mechanics College of SciencesShanghai University

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.

关键词： Double-stranded DNA. BiofilmElastic modu-lus - Cylinder model gaussian distribution

Thermally assisted switching in FePt single-domain particles with a gaussian distribution of temperature

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Science China(Physics,Mechanics & Astronomy) 2011年第7期54卷 1263-1266页

作者： TANG Ke YANG HongJie CAO LinHong YU HongTao LIU JinSong WANG JunXia School of Electronics and Electrical Engineering Chongqing University of Arts and Sciences Yongchuan 402160 China State Key Laboratory Cultivation Base for Nonmetal Composite and Functional Materials Southwest University of Science and Technology Mianyang 621010 China

Magnetic nanoscale systems,including nanodots,nanofibers,nanowires and nanoparticles,are currently attracting great interest due to their interesting physical and promising applications in various fields,such as magnetic recording,sensors,target drugs and catalysts,as well as *** achieve ultrahigh recording density,the method of heat assisted magnetic recording(HAMR) has been *** this work,with the help of a Monte Carlo method,the mechanisms of thermally assisted magnetization switching in FePt single-domain particles driven by an external magnetic field are investigated,where the temperature in the particles is assumed to follow a gaussian *** nucleation modes are observed for different distributions of *** is initiated by many droplets,which join each other at the boundary of the system;the other is ini-tiated by many droplets at the boundary,but in growth tending toward the inner part of the *** inverse proportional relationship between the metastable lifetime and the distribution is also found.

关键词： magnetization switching Monte Carlo simulation nucleation gaussian distribution

Derivation of gaussian Probability distribution: A New Approach

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Applied Mathematics 2020年第6期11卷 436-446页

作者： A. T. Adeniran O. Faweya T. O. Ogunlade K. O. Balogun Department of Statistics University of Ibadan Ibadan Nigeria Department of Statistics Ekiti State University (EKSU) Ado-Ekiti Nigeria Department of Mathematics Ekiti State University (EKSU) Ado-Ekiti Nigeria Department of Statistics Federal School of Statistics Ibadan Nigeria

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.

关键词： De Moivres Laplace Limit Theorem Binomial Probability Mass Function gaussian distribution Random Experiment

Plasma current tomography for HL-2A based on Bayesian inference

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Plasma Science and Technology 2024年第5期26卷 165-173页

作者：刘自结王天博吴木泉罗正平王硕孙腾飞肖炳甲李建刚 College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Southwestern Institute for Physics Chengdu 610200People’s Republic of China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China

An accurate plasma current profile has irreplaceable value for the steady-state operation of the *** this study,plasma current tomography based on Bayesian inference is applied to an HL-2A device and used to reconstruct the plasma current *** different Bayesian probability priors are tried,namely the Conditional Auto Regressive(CAR)prior and the Advanced Squared Exponential(ASE)kernel *** to the CAR prior,the ASE kernel prior adopts nonstationary hyperparameters and introduces the current profile of the reference discharge into the hyperparameters,which can make the shape of the current profile more flexible in *** results indicate that the ASE prior couples more information,reduces the probability of unreasonable solutions,and achieves higher reconstruction accuracy.

关键词： plasma current tomography Bayesian inference machine learning gaussian distribution

A gaussian Noise-Based Algorithm for Enhancing Backdoor Attacks

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Computers, Materials & Continua 2024年第7期80卷 361-387页

作者： Hong Huang Yunfei Wang Guotao Yuan Xin Li School of Computer Science and Engineering Sichuan University of Science&EngineeringYibin644000China

Deep Neural Networks(DNNs)are integral to various aspects of modern life,enhancing work ***-less,their susceptibility to diverse attack methods,including backdoor attacks,raises security *** aim to investigate backdoor attack methods for image categorization tasks,to promote the development of DNN towards higher *** 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 *** overcome these challenges,this study proposes a gaussian Noise-Targeted Universal Adversarial Perturbation(GN-TUAP)*** 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 *** limits anomalies within the perturbations improves their visual stealthiness,and makes them more challenging for defense methods to *** verify the effectiveness,stealthiness,and robustness of GN-TUAP,we proposed a comprehensive threat *** 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 *** also tested our perturbation triggers using various defense methods and further experimented on the robustness of the triggers against noise filtering *** experimental outcomes demonstrate that backdoor attacks leveraging perturbations generated via our algorithm exhibit cross-model attack effectiveness and superior ***,they possess robust anti-detection capabilities and maintain commendable performance when subjected to noise-filtering methods.

关键词： Image classification model backdoor attack gaussian distribution Artificial Intelligence(AI)security

Experimental study of regional fractal speckle produced in large angle scattering

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Chinese Physics B 2010年第7期19卷 256-262页

作者：宋洪胜程传福刘云燕刘桂媛滕树云 College of Physics and Electronics Shandong Normal University School of Science Shandong Jianzhu University School of Science Shandong University of Technology

Using the interference of speckle and the spherical reference wave, we extract the real and the imaginary parts of the complex amplitudes of the speckle in large angle scattering. By calculating the spatial correlation functions of intensity, we find that the speckle has a property of regional fractality, i.e. the fractal exponent equals 1 in a small spatial region and it becomes less than 1 in a bigger region. The empirical analytic expression of the intensity correlation function is gained. The probability density distributions of the intensities and the complex amplitudes show that the regional fractal speckle still obeys zero-mean circular complex gaussian statistics.

关键词： regional fractal speckle gaussian distribution

An improved deconvolution method for X-ray coded imaging in inertial confinement fusion

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Chinese Physics B 2013年第10期22卷 281-286页

作者：赵宗清何卫华王剑郝轶丹曹磊峰谷渝秋张保汉 Science and Technology on Plasma Physics Laboratory Laser Fusion Research Center China Academy of Engineering Physics

In inertial confinement fusion （ICF）, X-ray coded imaging is considered as the most potential means to diagnose the compressed core. The traditional Richardson-Lucy （RL） method has a strong ability to deblur the image where the noise follows the Poisson distribution. However, it always suffers from over-fitting and noise amplification, especially when the signal-to-noise ratio of image is relatively low. In this paper, we propose an improved deconvolution method for X-ray coded imaging. We model the image data as a set of independent gaussian distributions and derive the iterative solution with a maximum-likelihood scheme. The experimental results on X-ray coded imaging data demonstrate that this method is superior to the RL method in terms of anti-overfitting and noise suppression.

关键词： inertial confinement fusion coded imaging deconvolution gaussian distribution maximum-likelihood

Transverse effects in photorefractive two-wave mixing

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Chinese Physics B 2009年第5期18卷 1891-1897页

作者：蔡欣刘劲松汪盛烈刘时雄 Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and EngineeringHuazhong University of Science and Technology School of Science Wuhan University of Technology

In a biased photorefractive crystal, the process of two one-dimensional waves mixing, i.e., the dynamical evolution of both pump beam and signal beam, is traced by numerically solving the coupled-wave equation. Direct simulations show that the propagation and stability of the two beams are completely determined by the system parameters, such as the external bias field, the intensity and the beam waist of the pump beam. By adjusting these parameters, one can control the state of two gaussian waves mixing. The numerical results are helpful for performing a two-wave mixing experiment.

关键词： two-wave mixing transverse effects gaussian distribution photorefractive crystal