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A concise proof of Benford's law

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Fundamental Research 2024年第4期4卷 841-844页

作者： Luohan Wang bo-qiang Ma School of Physics Peking UniversityBeijing 100871China Center for High Energy Physics Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

This article presents a concise proof of the famous Benford's law when the distribution has a Riemann integrable probability density function and provides a criterion to judge whether a distribution obeys the *** proof is intuitive and elegant,accessible to anyone with basic knowledge of calculus,revealing that the law originates from the basic property of human number *** criterion can bring great convenience to the field of fraud detection.

关键词： Benford's law First-digit law Significant digit law Proof Criterion

利用LHAASO实验检验相对论并探索新物理

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物理 2024年第4期53卷 254-258页

作者：马伯强北京大学物理学院北京100871

中国高海拔宇宙线观测站(LHAASO)探测到了迄今最高能量的宇宙光子,其能量超过拍电子伏特量级,开启了超高能伽马天文学的新时代。LHAASO合作组完整记录了伽马暴GRB 221009A的全程爆发过程,首次测得来自伽马暴超出10 TeV的高能光子。这些... 详细信息

中国高海拔宇宙线观测站(LHAASO)探测到了迄今最高能量的宇宙光子,其能量超过拍电子伏特量级,开启了超高能伽马天文学的新时代。LHAASO合作组完整记录了伽马暴GRB 221009A的全程爆发过程,首次测得来自伽马暴超出10 TeV的高能光子。这些发现不仅对人们理解宇宙线起源具有重要意义,也为检验相对论并发现新物理提供了很好的契机。文章简要介绍LHAASO的这些观测结果,并指出这些结果可在检验爱因斯坦狭义相对论中洛伦兹不变性、恒定光速的基本假设,以及探索新物理机制的研究中发挥重要作用。

关键词：中国高海拔宇宙线观测站伽马天文学宇宙线起源相对论轴子

Bethe-Heitler lepton pair production in the deuteron breakup reaction

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Chinese Physics C 2024年第1期48卷 94-109页

作者：蔡孟初刘天博马伯强 School of Physics Peking UniversityBeijing 100871China Key Laboratory of Particle Physics and Particle Irradiation(MOE) Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China Center for High Energy Physics Peking UniversityBeijing 100871China

We study the lepton pair production via the Bethe-Heitler mechanism in the deuteron breakup *** complete seven-fold differential cross section is calculated with final state interactions taken into *** deuteron bound state is described by a relativistic covariant deuteron-nucleon *** numerical results indicate that the differential cross section is highly dependent on the lepton's azimuthal angle in regions of small polar angles and exhibits sharp peaks in the distribution over the invariant mass of the generated lepton pair or the two nucleons in the final *** demonstrate that such a nearly singular feature originates from the collinearity between the produced lepton or antilepton and the incident photon,and it is physically regularized by the lepton mass in our *** final state interaction between the knocked-out nucleon and recoil nucleon redistributes the differential cross section over the missing momentum,with a significant enhancement at a large missing momentum and a suppression in the intermediate *** a further decomposition of the final state interaction contribution,It is found that the on-shell term dominates the near quasi-elastic region,while the off-shell term dominates the other ***,we examine the contribution from the interference between the proton amplitude and neutron amplitude,which,as expected,is found negligible even if the proton-neutron rescattering is *** results of this study can serve as inputs for the analysis and background estimation of multiple exclusive measurements at Jefferson Lab and future electron-ion colliders.

关键词： Bethe-Heitler process deuteron breakup final state interactions

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自动化立体仓库在粮食仓储中的应用前景

粮油食品科技 2024年第1期32卷 146-152页

作者：张博强燕金浩吴兰韩志强孙朋河南工业大学机电工程学院河南郑州456001 中山市粮食储备经营管理有限公司广东中山528400

由于粮食产品的特殊性,粮食储存仓库的发展中,高新技术覆盖率较低。传统粮仓正在面临着土地资源有限、人工成本增加、卫生指标较差等问题。伴随着信息技术和物联网的发展,自动化立体仓库(简称“立库”)以无人化、信息化、密集化、高速... 详细信息

由于粮食产品的特殊性,粮食储存仓库的发展中,高新技术覆盖率较低。传统粮仓正在面临着土地资源有限、人工成本增加、卫生指标较差等问题。伴随着信息技术和物联网的发展,自动化立体仓库(简称“立库”)以无人化、信息化、密集化、高速化、无缝对接等优点在工业方面得到广泛的应用。在粮食仓储领域,以机械电子、自动化、控制、物流为基础的成品粮立体仓库有望解决粮食仓储之难题,以新技术带动传统粮食仓储行业确保国家粮食安全。

关键词：立体仓库成品粮自动化仓储

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基于卷积神经网络的火焰图像识别技术的研究

热能动力工程 2024年第2期39卷 184-193页

作者：周榕王博强王锴中国舰船研究设计中心湖北武汉430064 中国船舶集团有限公司第七○三研究所黑龙江哈尔滨150078

为提高卷积神经网络在火焰图像识别中的正确率、响应速度和抗误报警能力,实现对极早期火焰的有效探测和保证探测器的可靠性,针对卷积神经网络火焰识别算法进行改进,提出了一种采用双尺度去噪的深度可分离卷积火焰图像识别算法。通过对... 详细信息

为提高卷积神经网络在火焰图像识别中的正确率、响应速度和抗误报警能力,实现对极早期火焰的有效探测和保证探测器的可靠性,针对卷积神经网络火焰识别算法进行改进,提出了一种采用双尺度去噪的深度可分离卷积火焰图像识别算法。通过对移植该算法的火焰图像探测器进行响应速度和抗误报警实验和在与某型采用神经网络算法的火焰图像探测器的对比实验中分别发现:探测器对放置在距其15 m处的5 cm×5 cm的火盘响应速度为2.8 s;探测器对强光干扰源和高热干扰源有较强的抗干扰能力;采用改进算法的探测器在灵敏度、响应速度和抗干扰能力上均优于原始算法的探测器,说明采用双尺度去噪的深度可分离卷积火焰图像识别算法的火焰图像探测器对火焰具有更高的灵敏度、响应速度和较强抗干扰能力。

关键词：卷积神经网络火焰识别图像处理智能算法模型训练

Mean-square Stability of Stochastic Age-dependent Delay Population Systems with Jumps

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Acta Mathematicae Applicatae Sinica 2018年第1期34卷 145-154页

作者： qiang LI Qi-min ZHANG bo-qiang CAO School of Mathematics and Statistics Ningxia University Yinchuan 750021 China School of Mathematics and Information Sciences Beifang University of Nationalities Yinchuan 750021 China

In this paper, we present the compensated stochastic θ method for stochastic age-dependent delay population systems（SADDPSs） with Poisson jumps. The definition of mean-square stability of the numerical solution is given and a sufficient condition for mean-square stability of the numerical solution is derived. It is shown that the compensated stochastic θ method inherits stability property of the numerical solutions. Finally,the theoretical results are also confirmed by a numerical experiment.

关键词： stochastic age-dependent delay population systems compensated stochastic θ method poisson jumps mean-square stability

Light speed variation from active galactic nuclei

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Science Bulletin 2020年第4期65卷 262-266页

作者： Hao Li bo-qiang Ma School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China Center for High Energy Physics Peking UniversityBeijing 100871China Center for History and Philosophy of Science Peking UniversityBeijing 100871China

According to Einstein’s relativity,the speed of light is a constant in free ***,it is speculated from quantum gravity that the light speed may receive a correction in powers of E=EPl,where E is the energy of the photon and EPl?■≈1.22×10^19 GeV is the Planck *** the light speed might be energy dependent due to the Lorentz invariance violation(see,e.g.,Refs.[1–6]).Such speed variation is very tiny and can hardly be detected on the *** was suggested by Amelino-Camelia et al.[7]that photons from gamma-ray bursts(GRBs)can be used to detect the light speed variation.

关键词： red PKS 304 活动星系核光变曲线

A Proof of First Digit Law from Laplace Transform

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Chinese Physics Letters 2019年第7期36卷 1-5页

作者： Mingshu Cong bo-qiang Ma School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 Center for High Energy Physics Peking University Beijing 100871

The first digit law, also known as Benford’s law or the significant digit law, is an empirical phenomenon that the leading digit of numbers from real world sources favors small ones in a form log(1 + 1/d), where d= 1, 2,..., *** a law has been elusive for over 100 years because it has been obscure whether this law is due to the logical consequence of the number system or some mysterious mechanism of nature. We provide a simple and elegant proof of this law from the application of the Laplace transform, which is an important tool of mathematical methods in physics. It is revealed that the first digit law originates from the basic property of the number system, thus it should be attributed as a basic mathematical knowledge for wide applications.

关键词： The first digit law significant digit wide applications

Conductive Au nanowires regulated by silk fibroin nanofibers

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Frontiers of Materials Science 2014年第1期8卷 102-105页

作者： bo-Ju DONG qiang LU National Engineering Laboratory for Modern Silk College of Textile and Clothing Engineering Soochow University Suzhou 215123 China

Conductive Au-biopolymer composites have promising applications in tissue engineering such as nerve tissue regeneration. In this study, silk fibroin nanofibers were formed in aqueous solution by regulating silk self-assembly process and then used as template for Au nanowire fabrication. We performed the synthesis of Au seeds by repeating the seeding cycles for several times in order to increase the density of Au seeds on the nanofibers. After electroless plating, densely decorated Au seeds grew into irregularly shaped particles following silk nanofiber to fill the gaps between particles and finally form uniform continuous nanowires. The conductive property of the Au-silk fibroin nanowires was studied with current-voltage （I-V） measurement. A typical ohmic behavior was observed, which highlighted their potential applications in nerve tissue regeneration.

关键词： silk Au nanowire electrical conductivity biological device