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Generalized Hardy-type tests for hierarchy of multipartite non-locality
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作者 Fei Yang Yu Yuan +3 位作者 Wen-Lu Lin Shu-Ao Liao Cheng-Jie Zhang Qing Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期99-104,共6页
We propose a family of Hardy-type tests for an arbitrary n-partite system, which can detect different degrees of nonlocality ranging from standard to genuine multipartite non-locality. For any non-signaling m-local hi... We propose a family of Hardy-type tests for an arbitrary n-partite system, which can detect different degrees of nonlocality ranging from standard to genuine multipartite non-locality. For any non-signaling m-local hidden variable model,the corresponding tests fail, whereas a pass of this type of test indicates that this state is m non-local. We show that any entangled generalized GHZ state exhibits Hardy’s non-locality for each rank of multipartite non-locality. Furthermore, for the detection of m non-localities, a family of Bell-type inequalities based on our test is constructed. Numerical results show that it is more efficient than the inequalities proposed in [Phys. Rev. A 94 022110(2016)]. 展开更多
关键词 Hardy paradox Bell non-locality multipartite non-locality
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The relation between Hardy's non-locality and violation of Bell inequality
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作者 向阳 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期7-11,共5页
We give an analytic quantitative relation between Hardy's non-locality and Bell operator. We find that Hardy's non-locality is a sufficient condition for the violation of Bell inequality, the upper bound of Hardy's... We give an analytic quantitative relation between Hardy's non-locality and Bell operator. We find that Hardy's non-locality is a sufficient condition for the violation of Bell inequality, the upper bound of Hardy's non-locality allowed by information causality just corresponds to Tsirelson bound of Bell inequality and the upper bound of Hardy's non- locality allowed by the principle of no-signaling just corresponds to the algebraic maximum of Bell operator. Then we study the CabeUo's argument of Hardy's non-locality (a generalization of Hardy's argument) and find a similar relation between it and violation of Bell inequality. Finally, we give a simple derivation of the bound of Hardy's non-locality under the constraint of information causality with the aid of the above derived relation between Hardy's non-locality and Bell operator. 展开更多
关键词 Hardy's non-locality Bell inequality information causality
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Dynamics of measurement-induced non-locality and geometric discord with initial system-environment correlations
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作者 肖瑞林 肖兴 钟握军 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期280-284,共5页
We analyze the dynamics of geometric measure of discord (GMOD) and measurement-induced non-locality (MIN) in the presence of initial system-reservoir correlations without Born and Markov approximation. Although th... We analyze the dynamics of geometric measure of discord (GMOD) and measurement-induced non-locality (MIN) in the presence of initial system-reservoir correlations without Born and Markov approximation. Although the initial system-environment states have the same reduced density matrices for both the system and environment, the effects of different initial system-environment correlations have been shown to fundamentally alter the time evolution of GMOD and MIN between two quantum systems in both Markovian and non-Markovian regimes. In general, both GMOD and MIN experience a sudden increase for initially quantum-correlated states, and a sudden decrease for classical-correlated states before they reach the same stationary values with initially factorized states. 展开更多
关键词 geometric measure of discord measurement-induced non-locality initial correlations
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The “Non-Locality” of Entangled States Is Seeming Phenomenon
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作者 Marat Guryev 《Journal of Applied Mathematics and Physics》 2017年第9期1791-1796,共6页
EPR raised fundamental problems of non-locality (NL) in the case of entangled states (ES) 82 years ago. These problems were not solved until now. EPR and their followers used and would continue to use calculation meth... EPR raised fundamental problems of non-locality (NL) in the case of entangled states (ES) 82 years ago. These problems were not solved until now. EPR and their followers used and would continue to use calculation methods that were available at that time. However, we can easily explain this observable NL as a trivial result of conservation laws (CL) within modern quantum mechanics (MQM). But application of CL requires materialistic descriptions of reality in a micro world in contrast to so-called quantum measurement theory (QMT), which was created mainly in the times of EPR and is widely accepted until now. We have to use a materialistic description, just as many physicists who actually work with high precision do by default. In this article, practical examples are given for real, precise measurements of wave functions of molecules and crystals, which, of course, were not known to EPR and were not noticed by their followers. We should acknowledge that QMT is merely an unneeded complication of simple relations of MQM. NL is the seeming result of these complications. 展开更多
关键词 non-locality ENTANGLED States Quantum MEASUREMENT Theory EPR Electron DIFFRACTION Neutron DIFFRACTION y - RAY DIFFRACTION MEASUREMENT of Wave Function
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Long radial coherence of electron temperature fluctuations in non-local transport in HL-2A plasmas
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作者 石中兵 方凯锐 +14 位作者 李景春 邹晓岚 卢兆旸 闻杰 王占辉 丁玄同 陈伟 杨曾辰 蒋敏 季小全 佟瑞海 李永高 施陪万 钟武律 许敏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期413-420,共8页
The dynamics of long-wavelength(kθ<1.4 cm^(-1)),broadband(20 kHz–200 kHz)electron temperature fluctuations(Te/Te)of plasmas in gas-puff experiments are observed for the first time in HL-2A tokamak.In a relatively... The dynamics of long-wavelength(kθ<1.4 cm^(-1)),broadband(20 kHz–200 kHz)electron temperature fluctuations(Te/Te)of plasmas in gas-puff experiments are observed for the first time in HL-2A tokamak.In a relatively low density(ne(0)■0.91×10^(19)m^(-3)–1.20×10^(19)m^(-3))scenario,after gas-puffing the core temperature increases and the edge temperature drops.On the contrary,temperature fluctuation drops at the core and increases at the edge.Analyses show the non-local emergence is accompanied with a long radial coherent length of turbulent fluctuations.While in a higher density(ne(0)?1.83×10^(19)m^(-3)–2.02×10^(19)m^(-3))scenario,the phenomena are not observed.Furthermore,compelling evidence indicates that E×B shear serves as a substantial contributor to this extensive radial interaction.This finding offers a direct explanatory link to the intriguing core-heating phenomenon witnessed within the realm of non-local transport. 展开更多
关键词 nuclear fusion non-local transport TOKAMAK gas-puffing
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Fresnel Equations Derived Using a Non-Local Hidden-Variable Particle Theory
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作者 Dirk J. Pons 《Journal of Modern Physics》 2024年第6期950-984,共35页
Problem: The Fresnel equations describe the proportions of reflected and transmitted light from a surface, and are conventionally derived from wave theory continuum mechanics. Particle-based derivations of the Fresnel... Problem: The Fresnel equations describe the proportions of reflected and transmitted light from a surface, and are conventionally derived from wave theory continuum mechanics. Particle-based derivations of the Fresnel equations appear not to exist. Approach: The objective of this work was to derive the basic optical laws from first principles from a particle basis. The particle model used was the Cordus theory, a type of non-local hidden-variable (NLHV) theory that predicts specific substructures to the photon and other particles. Findings: The theory explains the origin of the orthogonal electrostatic and magnetic fields, and re-derives the refraction and reflection laws including Snell’s law and critical angle, and the Fresnel equations for s and p-polarisation. These formulations are identical to those produced by electromagnetic wave theory. Contribution: The work provides a comprehensive derivation and physical explanation of the basic optical laws, which appears not to have previously been shown from a particle basis. Implications: The primary implications are for suggesting routes for the theoretical advancement of fundamental physics. The Cordus NLHV particle theory explains optical phenomena, yet it also explains other physical phenomena including some otherwise only accessible through quantum mechanics (such as the electron spin g-factor) and general relativity (including the Lorentz and relativistic Doppler). It also provides solutions for phenomena of unknown causation, such as asymmetrical baryogenesis, unification of the interactions, and reasons for nuclide stability/instability. Consequently, the implication is that NLHV theories have the potential to represent a deeper physics that may underpin and unify quantum mechanics, general relativity, and wave theory. 展开更多
关键词 Wave-Particle Duality Optical Law Fresnel Equation non-local Hidden-Variable
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High performance“non-local”generic face reconstruction model using the lightweight Speckle-Transformer(SpT)UNet 被引量:1
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作者 Yangyundou Wang Hao Wang Min Gu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第2期1-9,共9页
Significant progress has been made in computational imaging(CI),in which deep convolutional neural networks(CNNs)have demonstrated that sparse speckle patterns can be reconstructed.However,due to the limited“local”k... Significant progress has been made in computational imaging(CI),in which deep convolutional neural networks(CNNs)have demonstrated that sparse speckle patterns can be reconstructed.However,due to the limited“local”kernel size of the convolutional operator,for the spatially dense patterns,such as the generic face images,the performance of CNNs is limited.Here,we propose a“non-local”model,termed the Speckle-Transformer(SpT)UNet,for speckle feature extraction of generic face images.It is worth noting that the lightweight SpT UNet reveals a high efficiency and strong comparative performance with Pearson Correlation Coefficient(PCC),and structural similarity measure(SSIM)exceeding 0.989,and 0.950,respectively. 展开更多
关键词 speckle reconstruction non-local model generic face images lightweight network
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Validity of non-local mean filter and novel denoising method 被引量:1
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作者 Xiangyuan LIU Zhongke WU Xingce WANG 《Virtual Reality & Intelligent Hardware》 EI 2023年第4期338-350,共13页
Background Image denoising is an important topic in the digital image processing field.This study theoretically investigates the validity of the classical nonlocal mean filter(NLM)for removing Gaussian noise from a no... Background Image denoising is an important topic in the digital image processing field.This study theoretically investigates the validity of the classical nonlocal mean filter(NLM)for removing Gaussian noise from a novel statistical perspective.Method By considering the restored image as an estimator of the clear image from a statistical perspective,we gradually analyze the unbiasedness and effectiveness of the restored value obtained by the NLM filter.Subsequently,we propose an improved NLM algorithm called the clustering-based NLM filter that is derived from the conditions obtained through the theoretical analysis.The proposed filter attempts to restore an ideal value using the approximately constant intensities obtained by the image clustering process.In this study,we adopt a mixed probability model on a prefiltered image to generate an estimator of the ideal clustered components.Result The experiment yields improved peak signal-to-noise ratio values and visual results upon the removal of Gaussian noise.Conclusion However,the considerable practical performance of our filter demonstrates that our method is theoretically acceptable as it can effectively estimate ideal images. 展开更多
关键词 Gaussian noise non-local means filter UNBIASEDNESS EFFECTIVENESS
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基于Non-local的腰椎间盘突出患者多裂肌分割方法
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作者 李夏 胡巍 王子民 《桂林电子科技大学学报》 2023年第3期217-222,共6页
为实现腰椎间盘突出患者多裂肌病灶部位的精确分割,提出了一种基于Non-local的腰椎间盘突出患者多裂肌分割方法。以U-Net网络为基础,通过构造混合池化卷积来代替编码器传统的卷积模块,以提高全局特征与局部特征之间的相关性并融合网络... 为实现腰椎间盘突出患者多裂肌病灶部位的精确分割,提出了一种基于Non-local的腰椎间盘突出患者多裂肌分割方法。以U-Net网络为基础,通过构造混合池化卷积来代替编码器传统的卷积模块,以提高全局特征与局部特征之间的相关性并融合网络高低维特征,增强了网络提取多裂肌特征的能力。然后,在网络的中间部署了一个由2个级联卷积组成的卷积模块。最后,经过由Non-local模块和3×3的卷积构成的解码器,通过引入注意力机制来更加关注目标的特征并抑制不必要的特征和噪音,从而提高模型的性能。实验结果表明,本方法与经典U-Net算法相比,Dice系数提升了9.5%,Jaccard相似系数提升了11.3%,Hausdorff Distance下降了74.6%。该方法提高了多裂肌脂肪浸润部位的分割精度,为腰椎间盘突出患者多裂肌病灶部位的分割提供了一种有效的方法。 展开更多
关键词 腰椎间盘突出症 核磁共振成像 U-Net non-locAL 图像分割
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Malus’ Law Derived from Deterministic Particle Behavior
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作者 Peter Schuttevaar 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期958-966,共9页
A polarized beam of energy is usually interpreted as a set of particles, all having the same polarization state. Difference in behavior between the one and the other particle is then explained by a number of counter-i... A polarized beam of energy is usually interpreted as a set of particles, all having the same polarization state. Difference in behavior between the one and the other particle is then explained by a number of counter-intuitive quantum mechanical concepts like probability distribution, superposition, entanglement and quantized spin. Alternatively, I propose that a polarized beam is composed of a set of particles with a cosine distribution of polarization angles within a polarization area. I show that Malus’ law for the intensity of a beam of polarized light can be derived in a straightforward manner from this distribution. I then show that none of the above-mentioned counter-intuitive concepts are necessary to explain particle behavior and that the ontology of particles, passing through a polarizer, can be easily and intuitively understood. I conclude by formulating some questions for follow-up research. 展开更多
关键词 Quantum Mechanics BELL Malus Law SUPERPOSITION ENTANGLEMENT Quantum Fields Spin Hidden Variables LOCALITY non-locality
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基于N-Unet视网膜血管分割
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作者 田红 陈姚节 《计算机应用与软件》 北大核心 2024年第4期219-223,共5页
针对在现阶段视网膜血管分割过程中存在的分支断裂问题,提出一种非局部Unet的模型Non-local Unet(N-Unet)。N-Unet模型保留了编码器-解码器的对称结构,在编码器阶段引入非局部块,使模型在提取特征的过程中关注非局部信息,能更好地捕捉... 针对在现阶段视网膜血管分割过程中存在的分支断裂问题,提出一种非局部Unet的模型Non-local Unet(N-Unet)。N-Unet模型保留了编码器-解码器的对称结构,在编码器阶段引入非局部块,使模型在提取特征的过程中关注非局部信息,能更好地捕捉图像中非相邻像素之间的关系。该模型在公开的DRIVE数据集上进行评估,得到的准确性、敏感性、特异性、曲线下面积分别为0.9523、0.8021、0.9743、0.8949。实验结果表明,该方法在解决血管分割过程中的分支断裂问题表现良好,具有研究意义。 展开更多
关键词 Unet网络 non-locAL 血管分割 医学图像
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基于Non-Local means滤波的雾天降质图像恢复算法 被引量:2
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作者 胡正平 荀娜娜 《四川兵工学报》 CAS 2010年第11期116-120,共5页
针对目前去雾算法易导致边缘晕环效应、边缘轮廓及景物特征比较模糊问题,提出了一种景深等先验信息未知条件下基于Non-Local means滤波的雾天降质图像恢复算法。首先,根据大气散射模型将经典的场景深度估计转化为大气面纱以及天空亮度估... 针对目前去雾算法易导致边缘晕环效应、边缘轮廓及景物特征比较模糊问题,提出了一种景深等先验信息未知条件下基于Non-Local means滤波的雾天降质图像恢复算法。首先,根据大气散射模型将经典的场景深度估计转化为大气面纱以及天空亮度估计,避免难求的场景深度图;然后,对雾天降质图像进行雾气平均化预处理,经过预处理图像平均亮度变小;其次,依据大气面纱的边缘跟雾天图像的低频具有大的相似性,采用Non-Localmeans滤波算法估计大气面纱模型;最后,为了使恢复图像的亮度跟色度都更加接近晴天图像,进行防止对比度放大的平滑与色度调整处理。通过与已有实验结果对比表明,提出的算法可以获得更精确的大气面纱,恢复图像不但边缘轮廓及景物特征都比较清楚,而且可有效抑制边缘晕环效应。 展开更多
关键词 大气散射模型 non-locAL MEANS 大气面纱 去雾程度 图像恢复
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Non-Local pH Shifts and Shared Changing Angular Velocity Magnetic Fields: Discrete Energies and the Importance of Point Durations 被引量:2
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作者 Nicolas Rouleau Trevor N. Carniello Michael A. Persinger 《Journal of Biophysical Chemistry》 2014年第2期44-53,共10页
Macroscopic productions of “non-locality” or “excess correlations” of dynamic changes within media between two spaces could be utilized as alternative communication systems. Previous experiments have shown that in... Macroscopic productions of “non-locality” or “excess correlations” of dynamic changes within media between two spaces could be utilized as alternative communication systems. Previous experiments have shown that injections of a weak acid within one of two volumes of spring water sharing the same patterned circular magnetic fields with changing angular accelerations separated by non-traditional (5 m) distances were associated with opposite (basic) shifts in pH within the non-injected, non-local volume. In the present experiments, employing a different technology, pairs of beakers separated by 1 m containing either 25 cc, 50 cc, or 100 cc of spring water were placed within toroids generating weak (30, 300 nT) changing acceleration magnetic fields with 1 ms, 2 ms, or 3 ms point durations or a field whose point durations changed. When a proton source (weak acid) was injected into one beaker (local) pH shifts in the other (non-local) beaker exhibit increased acidity for the 3 ms point duration but increased alkalinity for the 1 ms duration. Neither intermittent point durations nor variable point durations for the same volumes of water placed between the two magnetic field-coupled beakers exhibited significant changes from baseline. Contingent upon the point duration of the applied field, the pH shift was consistent with a fixed quantity of decreased free protons (increased pH) or increased protons (decreased pH) in the non-local beakers. The opposite directions of the pH shifts at 1 ms and 3 ms that correspond to quantitative cosmological solutions for electrons and protons suggest these results may reflect a fundamental physical process. 展开更多
关键词 EXCESS Correlations PH SHIFTS non-locality Novel Communication Systems
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One-step quantum dialogue
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作者 朱鹏辉 钟伟 +3 位作者 杜明明 李喜云 周澜 盛宇波 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期95-104,共10页
Quantum dialogue(QD)enables two communication parties to directly exchange secret messages simultaneously.In conventional QD protocols,photons need to transmit in the quantum channel for two rounds.In this paper,we pr... Quantum dialogue(QD)enables two communication parties to directly exchange secret messages simultaneously.In conventional QD protocols,photons need to transmit in the quantum channel for two rounds.In this paper,we propose a one-step QD protocol based on the hyperentanglement.With the help of the non-local hyperentanglement-assisted Bell state measurement(BSM),the photons only need to transmit in the quantum channel once.We prove that our one-step QD protocol is secure in theory and numerically simulate its secret message capacity under practical experimental condition.Compared with previous QD protocols,the one-step QD protocol can effectively simplify the experiment operations and reduce the message loss caused by the photon transmission loss.Meanwhile,the non-local hyperentanglement-assisted BSM has a success probability of 100%and is feasible with linear optical elements.Moreover,combined with the hyperentanglement heralded amplification and purification,our protocol is possible to realize long-distance one-step QD. 展开更多
关键词 one-step quantum dialogue hyperentanglement hyperentanglement distribution non-local Bell-state measurement
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基于改进YOWO算法的学生课堂行为识别
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作者 徐鑫磊 张景异 《计算机系统应用》 2024年第4期113-122,共10页
当前,大部分的学生课堂行为识别工作主要基于单帧图像进行,忽略了行为的连贯性,因此不能充分利用视频信息来对学生的课堂行为进行准确刻画.所以,本文提出一种改进的YOWO算法模型,有效利用视频信息对学生课堂行为进行识别.首先,本文采集... 当前,大部分的学生课堂行为识别工作主要基于单帧图像进行,忽略了行为的连贯性,因此不能充分利用视频信息来对学生的课堂行为进行准确刻画.所以,本文提出一种改进的YOWO算法模型,有效利用视频信息对学生课堂行为进行识别.首先,本文采集某高校真实课堂教学中的授课录像,制作出包含5类学生课堂行为的AVA格式视频数据集;其次,采用时移模块TSM(temporal shift module),用来增强模型获取时间上下文信息的能力;最后,采用非局部操作模块non-local来提高模型提取关键位置信息的能力.实验结果表明,通过对YOWO模型的优化,使得网络的识别性能更佳.在学生课堂行为数据集上,改进后的算法的mAP值为95.7%,相较于原YOWO算法在mAP值上提高了4.6%;模型参数量为81.97×10^(6),计算量为22.6 GFLOPs,参数量和计算量分别降低32.3%和9.6%;检测速度为24.03 f/s,提升了约3 f/s. 展开更多
关键词 YOWO算法 TSM non-locAL 学生课堂行为 行为识别 注意力机制
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Non-Local and Memory Character of Frictional Energy Dissipation on Atomic Scale
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作者 Sergey Yu. Krylov Joost W. M. Frenken 《Engineering(科研)》 2017年第1期14-21,共8页
The traditional description of atomic-scale friction, as investigated in Friction force microscopy, in terms of mechanical stick-slip instabilities appears so successful that it obscures the actual mechanisms of frict... The traditional description of atomic-scale friction, as investigated in Friction force microscopy, in terms of mechanical stick-slip instabilities appears so successful that it obscures the actual mechanisms of frictional energy dissipation. More sophisticated theoretical approach, which takes into account damping explicitly, reveals the existence of some hidden, unexplained problems, like the universal nearly-critical damping and unexpectedly high value of the dissipation rate. In this paper, we combine analysis in the framework of nonequilibrium statistical mechanics with simple atomistic modeling to show that the hidden problems of atomic scale friction find their origin in the nontrivial character of energy dissipation that is non-local and dominated by memory effects, which have not been addressed before in the context of dry, atomic-scale friction. 展开更多
关键词 NANOTRIBOLOGY ATOMIC SCALE Friction Dissipation non-locality MEMORY
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Neither Incomplete nor Non-Local, Just Entangled
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作者 Franz Kohl 《Journal of Quantum Information Science》 2021年第4期143-155,共13页
Bell-state experiments with pairs of polarization-entangled photons are interpreted without any hinge on non-local mechanisms. The presented model rests on a careful analysis of published experimental findings. These ... Bell-state experiments with pairs of polarization-entangled photons are interpreted without any hinge on non-local mechanisms. The presented model rests on a careful analysis of published experimental findings. These foundations are implemented into a standard quantum mechanical treatment that obeys the purely local nature of each polarization preparation in the course of a measurement process. Polarization entanglement is ascribed to the generation of indiscernible photon pairs while undistorted propagation maintains this interrelation. Thus, the proposed approach assigns the essential characteristics of polarization entanglement to each constituent of an entangled pair. Accordingly, space-time separated polarization preparations lead to consistent probabilities of joint detection events. The obtained results agree with those of previous non-local models and thus reproduce the experimentally required violations of the Bell inequality. Since the presented approach lacks any non-local phenomenon, hidden variables are rendered superfluous, too. 展开更多
关键词 Quantum non-locality Polarization Entanglement Bell Experiments
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GURTIN-TYPE VARIATIONAL PRINCIPLES FOR DYNAMICS OF A NON-LOCAL THERMAL EQUILIBRIUM SATURATED POROUS MEDIUM 被引量:22
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作者 YangXiao 《Acta Mechanica Solida Sinica》 SCIE EI 2005年第1期37-45,共9页
Based on the porous media theory and by taking into account the efects of the pore fuid viscidity, energy exchanges due to the additional thermal conduction and convection between solid and fuid phases, a mathematical... Based on the porous media theory and by taking into account the efects of the pore fuid viscidity, energy exchanges due to the additional thermal conduction and convection between solid and fuid phases, a mathematical model for the dynamic-thermo-hydro-mechanical coupling of a non-local thermal equilibrium fuid-saturated porous medium, in which the two constituents are assumed to be incompressible and immiscible, is established under the assumption of small de- formation of the solid phase, small velocity of the fuid phase and small temperature changes of the two constituents. The mathematical model of a local thermal equilibrium fuid-saturated porous medium can be obtained directly from the above one. Several Gurtin-type variational principles, especially Hu-Washizu type variational principles, for the initial boundary value problems of dy- namic and quasi-static responses are presented. It should be pointed out that these variational principles can be degenerated easily into the case of isothermal incompressible fuid-saturated elastic porous media, which have been discussed previously. 展开更多
关键词 non-local thermal equilibrium thermal-mechanical coupling mathematical model variational principle porous media theory
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基于non-local先验的贝叶斯变量选择方法及其在高维数据分析中的应用
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作者 马金沙 董晓强 +4 位作者 高倩 陶然 许树红 李艳艳 王彤 《中国卫生统计》 CSCD 北大核心 2020年第3期372-377,383,共7页
目的对高维数据进行变量筛选并构建预测模型是组学数据分析的研究热点之一。本研究旨在为结局为二分类变量的高维组学数据筛选自变量并构建预测结局的稀疏统计模型。方法本研究通过模拟研究和实例分析阐释基于non-local先验的贝叶斯变... 目的对高维数据进行变量筛选并构建预测模型是组学数据分析的研究热点之一。本研究旨在为结局为二分类变量的高维组学数据筛选自变量并构建预测结局的稀疏统计模型。方法本研究通过模拟研究和实例分析阐释基于non-local先验的贝叶斯变量选择方法--乘积逆矩先验(product inverse moment,piMOM)相较于惩罚类方法ISIS-光滑平切绝对偏差(iterative sure independence screening-smoothly clipped absolute deviation,ISIS-SCAD)和ISIS-最小最大凹惩罚(iterative sure independence screening-minimax concave penalty,ISIS-MCP)在高维数据中变量筛选及其预测效果的性能优劣。结果模拟研究发现:在高维的情况下,经piMOM、ISIS-SCAD和ISIS-MCP方法筛选所得变量的平均真阳性数和受试者工作特征曲线下面积(AUC,area under curve)基本相等,ISIS-SCAD、ISIS-MCP的平均假阳性数、回归系数均方误差以及预测均方误差明显高于基于non-local先验的贝叶斯变量方法所获得的对应值。piMOM方法分析弥漫大B细胞淋巴瘤实例数据共识别5个有意义的基因,AUC为0.996;ISIS-SCAD识别7个基因,AUC为0.975;ISIS-MCP识别7个基因,AUC为0.968。结论在模型选择相合性和预测准确性方面,piMOM方法与ISIS-SCAD和ISIS-MCP相比,具有优势,在一定意义上可有效控制假阳性率。 展开更多
关键词 高维数据 贝叶斯变量选择方法 non-local先验 乘积逆矩先验 弥漫性大B细胞淋巴瘤
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Surface effect and non-local elasticity in wave propagation of functionally graded piezoelectric nano-rod excited to applied voltage 被引量:5
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作者 M.AREFI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第3期289-302,共14页
A non-local solution for a functionally graded piezoelectric nano-rod is pre- sented by accounting the surface effect. This solution is used to evaluate the charac- teristics of the wave propagation in the rod structu... A non-local solution for a functionally graded piezoelectric nano-rod is pre- sented by accounting the surface effect. This solution is used to evaluate the charac- teristics of the wave propagation in the rod structure. The model is loaded under a two-dimensional (2D) electric potential and an initially applied voltage at the top of the rod. The mechanical and electrical properties are assumed to be variable along the thick- ness direction of the rod according to the power law. The Hamilton principle is used to derive the governing differential equations of the electromechanical system. The effects of some important parameters such as the applied voltage and gradation of the material properties on the wave characteristics of the rod are studied. 展开更多
关键词 wave propagation non-local elasticity surface effect Love rod model non-homogeneous index voltage
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